ALBERT

Description: Purpose Urban flooding in developing countries of the Global South is growing due to extreme rainfall and sea-level rise induced by climate change, as well as the proliferation of impervious, built-up areas resulting from unplanned urbanisation and development. Continuous loss of traditional knowledge related to local water management practices, and the de-valuing of such knowledge that goes hand-in-hand with globalised aspirations, is inhibiting flood resilience efforts. This paper aims to address the need to include traditional water knowledge (TWK) in urban living and development processes in the Global South. Design/methodology/approach This paper commences with a review of existing frameworks that focus on natural resource management, critically assessing two existing frameworks of traditional ecological knowledge (TEK). The assessment of the existing approaches contributes to this paper’s development of a novel framework to promote TWK with regard to resilience and risk reduction, specifically for developing flood adaptive strategies, which is the second stage of this paper. Finally, the paper explains how the framework can contribute to the field of urban design and planning using examples from the literature to demonstrate challenges and opportunities related to the adaptation of such a framework. Findings The framework developed in this paper reveals three proposed vertices of TWK, named as place-based landscape knowledge, water use and management and water values. This framework has the potential to produce context-specific knowledge that can contribute to flood-resilient built-environment through urban design and practices. Research limitations/implications The framework developed in this paper reveals three proposed vertices of TWK, named place-based landscape knowledge, water use and management and water values. This framework has the potential to produce context-specific knowledge that can contribute to flood-resilient built-environment through urban design and practices. Originality/value Within the field of TEK research, very few researchers have explored the field of developing flood resilience in an urban context. The proposed TWK framework presented in this paper will help to fill that gap.

Description: Purpose In recent years, firms tend to direct their attention in communicating their environmental actions with their stakeholders. However, the level of environmental disclosers varies significantly among firms. This paper aims to explain the variation in environmental disclosure of firms based on their ownership type, namely – state ownership and institutional ownership. The study further aims to understand whether and how the relationship between ownership structure and environmental disclosure changes regarding countries’ development levels. Design/methodology/approach This paper uses a sample of 27,847 firm-year observations from 72 countries/economic districts between the years 2002 and 2017 and regression analysis to test how the relationship between different ownership structures and environmental disclosure and whether this relation is conditional on countries’ development levels. Findings This study finds that firms with higher state ownership have higher environmental disclosures and higher institutional ownership has a negative effect on environmental disclosures. Furthermore, this paper also documents that firms with higher state ownership and operating in developed countries have incrementally higher environmental disclosure, relative to firms operating in developing countries. Research limitations/implications The study has limitations that would provide possible starting points for further research. The first limitation is related to the environmental disclosure measure, which reflects the level of environmental disclosure of firms based on their disclosure information given in the Thomson Reuters, Asset4 database. A more refined measure can be constructed using hand-collected data based on linguistic analysis, which may reflect not only the level of the disclosure but also the quality of the environmental disclosure. The second limitation is the limited focus of the study toward state and institutional shareholding. Therefore, future research may consider examining the different types of ownership such as family ownership. Practical implications The findings of the study may help policymakers and regulators to consider the potential impact of various ownership types on environmental disclosures. Also, given the impact of countries’ development levels, regulators should consider that a one-size-fits-all is not applicable in environmental disclosures. Therefore, each country should consider the institutional dynamics of their operating environment to set appropriate regulations to enhance environmental disclosures. Social implications From a social perspective, the findings indicate that firms’ stakeholder engagement via environmental disclosures depends on the type of the controlling shareholders. Originality/value This study contributes to the literature by developing a new construct for environmental disclosure based on Biodiversity, Climate Change, Environmental Investments and Spill Impact Reduction performance measures. Further, grounding on legitimacy and stakeholder theories, this study shows the influence of ownership type on environmental disclosures and how this effect changes in accordance with the countries’ development.

Description: Let G k , n ℂ for 2 ≤ k

Description: Motivated by applications in evacuation planning, we consider a problem of optimizing flow with arc reversals in which the transit time depends on the orientation of the arc. In the considered problems, the transit time on an arc may change when it is reversed, contrary to the problems considered in the existing literature. Extending the existing idea of auxiliary network construction to allow asymmetric transit time on arcs, we present strongly polynomial time algorithms for solving single-source-single-sink maximum dynamic contraflow problem and quickest contraflow problem. The results are substantiated by a computational experiment in a Kathmandu road network. An algorithm to solve the corresponding earliest arrival contraflow problem with a pseudo-polynomial-time complexity is also presented. The partial contraflow approach for the corresponding problems has also been discussed.

Description: Mixed estimators in nonparametric regression have been developed in models with one response. The biresponse cases with different patterns among predictor variables that tend to be mixed estimators are often encountered. Therefore, in this article, we propose a biresponse nonparametric regression model with mixed spline smoothing and kernel estimators. This mixed estimator is suitable for modeling biresponse data with several patterns (response vs. predictors) that tend to change at certain subintervals such as the spline smoothing pattern, and other patterns that tend to be random are commonly modeled using kernel regression. The mixed estimator is obtained through two-stage estimation, i.e., penalized weighted least square (PWLS) and weighted least square (WLS). Furthermore, the proposed biresponse modeling with mixed estimators is validated using simulation data. This estimator is also applied to the percentage of the poor population and human development index data. The results show that the proposed model can be appropriately implemented and gives satisfactory results.

Description: In the present paper, we summarize the results of the research devoted to the problem of stability of the fluid flow moving in a channel with flexible walls and interacting with the walls. The walls of the vessel are subject to traveling waves. Experimental data show that the energy of the flowing fluid can be transferred and consumed by the structure (the walls), inducing “traveling wave flutter.” The problem of stability of fluid-structure interaction splits into two parts: (a) stability of fluid flow in the channel with harmonically moving walls and (b) stability of solid structure participating in the energy exchange with the flow. Stability of fluid flow, the main focus of the research, is obtained by solving the initial boundary value problem for the stream function. The main findings of the paper are the following: (i) rigorous formulation of the initial boundary problem for the stream function, ψ x , y , t , induced by the fluid-structure interaction model, which takes into account the axisymmetric pattern of the flow and “no-slip” condition near the channel walls; (ii) application of a double integral transformation (the Fourier transformation and Laplace transformation) to both the equation and boundary and initial conditions, which reduces the original partial differential equation to a parameter-dependent ordinary differential equation; (iii) derivation of the explicit formula for the Fourier transform of the stream function, ψ ˜ k , y , t ; (iv) evaluation of the inverse Fourier transform of ψ ˜ k , y , t and proving that reconstruction of ψ x , y , t can be obtained through a limiting process in the complex k -plane, which allows us to use the Residue theorem and represent the solution in the form of an infinite series of residues. The result of this research is an analytical solution describing blood flowing through a channel with flexible walls that are being perturbed in the form of a traveling wave.

Description: Purpose This paper aims to focus on reducing the vulnerability of Ahvaz city against urban disasters and lowering the number of casualties and amount of financial losses using modern approaches to develop resilience strategies that can increase urban safety to an acceptable level. The strategic situation of Ahvaz city, because of its abundant resources, the war experience and its location on the boundary regions of Iran, highlights its significance. Ahvaz has a high population and an extended texture, and the existence of extraordinary constructions increases the importance of physical resilience in this city. Design/methodology/approach The present study investigates built environment aspects such as the urban structure, the urban form, land-use proximity pattern, urban road network and crucial and vulnerable centres in Ahvaz, using a combination of qualitative and quantitative methods. Hence, the areas at risk in Ahvaz were identified and illustrated in a comprehensive risk assessment map, and then, by using the strengths, weaknesses, opportunities and threats technique and finally by using the Delphi method, some strategies and plans were presented to reduce the level of vulnerability in Ahvaz. Then, these strategies are prioritized by applying quality function deployment (QFD) technique. Findings The risk assessment result shows that most parts of Ahvaz’s urban areas are highly at risk. The central and northern parts of Ahvaz have the highest vulnerability at a time of crisis. These zones include district 1 (city centre) and districts 2, 3 and 7 at the city’s margins. The result of QFD process showed that the essential urban resilience strategy is to positively consider the passive defence studies with a physical resilience approach. Also, the proper distribution of strategic points in the city, moving the industrial and oil companies from the peripheral area, and facilitating access to vital, crucial centres to support urban regions are considered the most effective strategic plans. Originality/value This paper, with an integrated approach, examines and prioritizes the main physical problems of Ahvaz city based on the spatial analysis and opinions of experts. The physical strategies presented in this paper can significantly reduce the risks and increase the urban resilience of Ahvaz city in the face of crisis.

Description: Purpose This paper aims to investigate the emergence of new success measures for buildings and infrastructure post-disaster reconstruction projects, beyond the traditional ”iron triangle”, which have gained prominence with the increased involvement of clients and end-users in these projects. Consequently, the industry is obliged to reconsider the critical factors regarding what constitutes a successful outcome from the perspectives of these stakeholders. Design/methodology/approach Data was gathered from end-users in four Caribbean islands using a questionnaire survey on eight empirical success indicators obtained from an extensive systematic literature review. To elicit a ranking and correlations amongst the end-user’ perspectives on the indicators, factor analysis and structural equation modelling techniques (SEM) were conducted. Findings The factor analysis found “safety” to be the most important empirical success measure, while “change” ranked the least important. Correlation analysis using SEM identified two new composite indicators, namely, “competence” with delivering timely and quality environmentally friendly and sustainable projects and “adaptability” in ensuring project objectives reflect beneficiaries’ expectations amidst internal and external influences, to be critical of end-users’ measurement indicators that describe their assessment mechanism. Measurement and structural models validated “safety” and “satisfaction” to be the highest loading variables in the two composites, respectively. Research limitations/implications The research focussed on findings in English language articles; therefore, any claim to a complete list of indicators from the literature can be amiss. Practical implications Results confirm the traditional “iron triangle” of time, cost and quality to be limited in assessing reconstruction project outcomes and the views and expectations of the potential beneficiaries need to be factored in the planning, design, execution and post-handover stages in all reconstruction projects. Originality/value This paper was very specific in its attempt to investigate new success indicators for reconstruction project outcomes, aiming to assist with developing comprehensive project objectives that resonate with all stakeholder groups.

Description: PurposeThis paper describes the educational experiences of children and youth (aged 3–20) with disabilities during school closures resulting from the 2017 Northern California wildfires. Students with disabilities are particularly vulnerable to the adverse impacts of disaster, yet the effects of school closures on these children remains understudied. This study identifies considerations for students with disabilities and their families post-disaster.Design/methodology/approachAn inductive, qualitative approach was used for the study design, methodology and analysis. In-depth interviews were conducted with parents of 14 students with disabilities about their experiences during and following school closures. All of these children had missed between a week and over a month of school as a result of the wildfires. Thematic analysis was used to code data and identify four themes present across the data.FindingsOur findings indicate that children and youth with disabilities experienced disruptions in school-based services; lost previously acquired skills; exhibited negative health and behavioral issues; had difficulties adapting to new, unfamiliar routines and were saddened by lost social connections. Additionally, findings pinpoint the importance of social connections while schools were closed, the benefits of resuming school which included access to responsive school staff, as well as challenges faced by children with disabilities and their families once schools reopened.Originality/valueFamilies of children with disabilities, as illustrated in this study, often must transverse a different post-disaster landscape. Schools should assist them in navigating that landscape so students with disabilities can experience a more equitable return to education post-disaster.

Description: PurposeLearning at the local level is an important contributor to safe and resilient communities. The purpose of this article is therefore to explore what motivates municipalities in Norway to learn from disasters and how they learn from them. This purpose has been fulfilled by (1) addressing the process of learning from disasters occurring within municipalities, and (2) learning from disasters in other municipalities, in particular from the terrorist incidents that occurred in Oslo on 22 July 2011.Design/methodology/approachAn interview study was conducted of individuals responsible for municipal emergency preparedness.FindingsUnwanted events that occur outside municipal borders only trigger learning processes if they are geographically proximate. Events occurring within the geographical borders of the municipality represent greater potential for learning than those occurring outside its borders. Availability of resources for municipal civil protection activities is another factor that has an impact on learning.Originality/valueThe local level plays a key role in generating and maintaining adequate civil protection and emergency preparedness in society. Although the literature on learning from disasters is extensive, learning processes at the local level have been given little attention. This article thus contributes to the existing body of knowledge by studying learning processes following disasters at the local level.

Description: Analytical solutions for the transient single-phase and two-phase inward solid-state diffusion and solidification applied to the radial cylindrical and spherical geometries are proposed. Both solutions are developed from the differential equation that treats these phenomena in Cartesian coordinates, which are modified by geometric correlations and suitable changes of variables to achieve closed-form solutions. The modified differential equations are solved by using two well-known closed-form solutions based on the error function, and then equations are obtained to analyze the diffusion interface position as a function of time and position in cylinders and spheres. These exact correlations are inserted into the closed-form solutions for the slab and are used to update the roots for each radial position of the moving boundary interface. The predictions provided by the proposed analytical solutions are validated against the results of a numerical approach. Finally, a comparative study of diffusion in slabs, cylinders, and spheres is also presented for single-phase and two-phase solid-state diffusion and solidification, which shows the importance of the effects imposed by the radial cylindrical and spherical curvatures with respect to the Cartesian coordinate system in the process kinetics. The analytical model is proved to be general, as far as, a semi-infinite solution for diffusion problems with phase change exists in the form of the error function, which enables exact closed-form analytical solutions to be derived, by updating the root at each radial position the moving boundary interface.

Description: The contraflow approach has been extensively considered in the literature for modeling evacuations and has been claimed, due to its lane-direction-reversal capability, as an efficient idea to speed up the evacuation process. This paper considers the contraflow evacuation model on network with prioritized capacitated vertices that allows evacuees to be held at intermediate spots too, respecting their capacities and priority order. In particular, it studies the maximum flow evacuation planning problem and proposes polynomial and pseudo-polynomial time solution algorithms for static network and dynamic multinetwork, respectively. A real dataset of Kathmandu road network with evacuation spaces is considered to implement the algorithm designed for dynamic multinetwork and to observe its computational performance.

Description: Purpose Climatic extreme events are predicted to occur more frequently and intensely and will significantly threat the living of residents in arid and semi-arid regions. Therefore, this study aims to assess climatic extremes’ response to the emerging climate change mitigation strategy using a marine cloud brightening (MCB) scheme. Design/methodology/approach Based on Hadley Centre Global Environmental Model version 2-Earth System model simulations of a MCB scheme, this study used six climatic extreme indices [i.e. the hottest days (TXx), the coolest nights (TNn), the warm spell duration (WSDI), the cold spell duration (CSDI), the consecutive dry days (CDD) and wettest consecutive five days (RX5day)] to analyze spatiotemporal evolution of climate extreme events in the arid Sahara-Sahel-Arabian Peninsula Zone with and without MCB implementation. Findings Compared with a Representative Concentration Pathways 4.5 scenario, from 2030 to 2059, implementation of MCB is predicted to decrease the mean annual TXx and TNn indices by 0.4–1.7 and 0.3–2.1°C, respectively, for most of the Sahara-Sahel-Arabian Peninsula zone. It would also shorten the mean annual WSDI index by 118–183 days and the mean annual CSDI index by only 1–3 days, especially in the southern Sahara-Sahel-Arabian Peninsula zone. In terms of extreme precipitation, MCB could also decrease the mean annual CDD index by 5–25 days in the whole Sahara and Sahel belt and increase the mean annual RX5day index by approximately 10 mm in the east part of the Sahel belt during 2030–2059. Originality/value The results provide the first insights into the impacts of MCB on extreme climate in the arid Sahara-Sahel-Arabian Peninsula zone.

Description: This paper presents a mathematical model of glucose-insulin dynamics which is specific for type 2 diabetic patients. The general modelling is obtained by simplification of a global compartmental model by John Thomas Sorensen. The model parameters are estimated using nonlinear optimization and data collected in Rwanda for type 2 diabetic patients. In order to identify and evaluate possible abnormalities of type 2 diabetic patients, the Sampling Importance Resampling (SIR) particle filtering algorithm is used and implemented through discretization of the developed mathematical model. This process is done by clamping insulin and glucose concentrations at around clinical trial values as proposed by Defronzo. Furthermore, for detecting potential abnormalities in type 2 diabetic patients, we compare our results with results obtained from a simulation of the mathematical model for healthy subjects. The proposed mathematical model allows further investigation of the dynamic behavior of glucose, insulin, glucagon, stored insulin, and labile insulin in different organs for type 2 diabetic patients.

Description: Research has shown that current health expenditure in most countries, especially in sub-Saharan Africa, is inadequate and unsustainable. Yet, fraud, abuse, and waste in health insurance claims by service providers and subscribers threaten the delivery of quality healthcare. It is therefore imperative to analyze health insurance claim data to identify potentially suspicious claims. Typically, anomaly detection can be posited as a classification problem that requires the use of statistical methods such as mixture models and machine learning approaches to classify data points as either normal or anomalous. Additionally, health insurance claim data are mostly associated with problems of sparsity, heteroscedasticity, multicollinearity, and the presence of missing values. The analyses of such data are best addressed by adopting more robust statistical techniques. In this paper, we utilized the Bayesian quantile regression model to establish the relations between claim outcome of interest and subject-level features and further classify claims as either normal or anomalous. An estimated model component is assumed to inherently capture the behaviors of the response variable. A Bayesian mixture model, assuming a normal mixture of two components, is used to label claims as either normal or anomalous. The model was applied to health insurance data captured on 115 people suffering from various cardiovascular diseases across different states in the USA. Results show that 25 out of 115 claims (21.7%) were potentially suspicious. The overall accuracy of the fitted model was assessed to be 92%. Through the methodological approach and empirical application, we demonstrated that the Bayesian quantile regression is a viable model for anomaly detection.

Description: In this paper, we study a decomposition D -module structure of the polynomial ring. Then, we illustrate a geometric interpretation of the Specht polynomials. Using Brauer’s characterization, we give a partial generalization of the fact that factors of the discriminant of a finite map π : spec B ⟶ spec A generate the irreducible factors of the direct image of B under the map π .

Description: We investigate a class of locally conformal almost Kähler structures and prove that, under some conditions, this class is a subclass of almost Kähler structures. We show that a locally conformal almost Kähler manifold admits a canonical foliation whose leaves are hypersurfaces with the mean curvature vector field proportional to the Lee vector field. The geodesibility of the leaves is also characterized, and their minimality coincides with the incompressibility of the Lee vector field along the leaves.

Description: Purpose Housing infrastructure is the basic need for people of a community and due to disaster many houses may severaly damaged. Stakeholders and decision makers should focus on this issue and make the infrastructure more resilient against natural hazards. As dependency plays a very important role in resilience, it is important to study the dependencies and correlations among the housing infrastructure resilience factors. The evaluation of dependencies involve vagueness due to subjective judgement of experts. Design/methodology/approach In this work, the interaction between the housing infrastructure resilience factors are evaluated by using two different approaches such as crisp DEMATEL (Decision-Making and Trial Evaluation Laboratory) and rough DEMATEL (intregated crisp DEMATEL and rough set theory), where rough theory addressed the involvement of vagueness. These two approaches are compared with each other to find the effectiveness of rough DEMATEL over crisp DEMATEL. Findings The important factors of housing infrastructure resilience are identified by using both the approaches against flood hazard. Research limitations/implications The limitation of rough DEMATEL method is that it does not differentiate the type of influence such as positive or negative. Practical implications The outcome of the work will helps the stakeholders and ecission makers to make the infrastructure more resilient. Originality/value This study identify the imporatnat resilience factors of housing infrastructure against flood hazard by using two methodologies.

Description: Purpose This paper aims to present the “Vulnerability Sourcebook” methodology, a standardised framework for the assessment of climate vulnerability and risk in the context of adaptation planning. The Vulnerability Sourcebook has been developed for the Deutsche Gesellschaft für Internationale Zusammenarbeit (GIZ) and has been applied in more than twenty countries worldwide. Design/methodology/approach It is based on a participative development of so-called climate impact chains, which are an analytical concept to better understand, systemise and prioritise the climate factors as well as environmental and socio-economic factors that drive climate related threats, vulnerabilities and risks in a specific system. Impact chains serve as the backbone for an operational climate vulnerability assessment with indicators based on quantitative approaches (data, models) combined with expert assessments. In this paper, the authors present the concept and applications of the original Vulnerability Sourcebook, published in 2015, which was based on the IPCC AR4 concept of climate vulnerability. In Section 6 of this paper, the authors report how this concept has been adapted to the current IPCC AR5 concept of climate risks. Findings The application of the Sourcebook is demonstrated in three case studies in Bolivia, Pakistan and Burundi. The results indicate that particularly the participative development of impact chains helped with generating a common picture on climate vulnerabilities and commitment for adaptation planning within a region. The mixed methods approach (considering quantitative and qualitative information) allows for a flexible application in different contexts. Challenges are mainly the availability of climate (change) and socio-economic data, as well as the transparency of value-based decisions in the process. Originality/value The Vulnerability Sourcebook offers a standardised framework for the assessment of climate vulnerability and risk in the context of adaptation planning.

Description: PurposeReturn-entry is understudied in the disaster science literature. This paper provides an overview of the return-entry process, identifies key factors informing the selection of return strategy, proposes a simple classification of return strategies and offers ideas for advancing research in this area.Design/methodology/approachThis paper explores previous research and recent return-entry processes in order to advance understanding of strategies emergency managers employ and decisions they make when managing the return movement of evacuees home after disasters.FindingsThe paper offers new insights into the management of the return movement, proposes primary factors considered when developing return strategies and offers a framework for the selection of strategies utilized by emergency managers.Originality/valueGiven that return-entry is a burgeoning area of inquiry in disaster science, this paper advances knowledge and understanding of return-entry movements after disasters and outlines key research needs.

Description: We provide a characterization of the finite dimensionality of vector spaces in terms of the right-sided invertibility of linear operators on them.

Description: The concept of frames in Hilbert spaces continues to play a very interesting role in many kinds of applications. In this paper, we study the notion of dual continuous K -g-frames in Hilbert spaces. Also, we establish some new properties.

Description: Any continuous function with values in a Hausdorff topological space has a closed graph and satisfies the property of intermediate value. However, the reverse implications are false, in general. In this article, we treat additional conditions on the function, and its graph for the reverse to be true.

Description: For a Gaussian prime π and a nonzero Gaussian integer β = a + b i ∈ ℤ i with a ≥ 1 and β ≥ 2 + 2 , it was proved that if π = α n β n + α n − 1 β n − 1 + ⋯ + α 1 β + α 0 ≕ f β where n ≥ 1 , α n ∈ ℤ i 0 , α 0 , … , α n − 1 belong to a complete residue system modulo β , and the digits α n − 1 and α n satisfy certain restrictions, then the polynomial f x is irreducible in ℤ i x . For any quadratic field K ≔ ℚ m , it is well known that there are explicit representations for a complete residue system in K , but those of the case m ≡ 1   mod 4 are inapplicable to this work. In this article, we establish a new complete residue system for such a case and then generalize the result mentioned above for the ring of integers of any imaginary quadratic field.

Description: Purpose In recent years, cities have been facing economic, social and environmental crises that need to be prevented and dealt with. The new subject that has been brought up to improve city resistance to crises is urban resilience. The purpose of this study is to compare the resilience of Tehran and Mashhad to identify the strengths and weaknesses of these two cities for better planning in critical situations. Design/methodology/approach The research methodology is a comparative survey. The importance of the subject was manifested through a literature review. A questionnaire is designed using “the Rockefeller Foundation and ARUP’s model” and the Delphi method for testing 21 research hypotheses to evaluate resilience in the two cities (12 Delphi questionnaires and 232 urban resilience questionnaires). The data is analyzed using independent samples t-test by SPSS software. Findings The results show that both the cities are weak in terms of resilience indicators and sub-indicators, but Mashhad is more resilient than Tehran. Originality/value This paper compares urban resilience in Iran for the first time through a comparative study between two metropolises in the country. The Delphi method also is used for the first time (in Iranian case studies) to obtain the dimensions of urban resilience. By comparing the two cities, we can better understand their strengths and weaknesses.

Description: Purpose Degradable mulch film (DMF) is a potential alternate to polyethylene (PE) mulching. In this regard, the purpose of this paper is to explore the effects and paths of natural disaster shock and risk aversion influencing farmers’ DMF adoption. Design/methodology/approach This research is conducted by collecting cross-sectional data of corn farmers in Zhangye, China. First, by using the Tobit model, the paper attempts to explore the effects of natural disaster shock and risk aversion influencing farmers’ DMF adoption. Second, IV-Tobit model is applied to deal with endogenous problems between risk aversion and DMF adoption. Additionally, the researchers used a moderating model to analyze feasible paths of natural disaster shock and risk aversion impacting farmers’ DMF adoption. Findings The outcomes show that natural disaster shock and risk aversion significantly and positively affect farmers’ DMF adoption. Though risk aversion plays a significant moderating effect in influencing farmers’ DMF adoption by natural disaster shock, the moderating effect has a serious disguising effect. By considering the heterogeneity of risk aversion, the paper further confirms that if the intensity of natural disaster shock is increased by one unit, the intensity of MDF adoption by farmers with high-risk aversion also tends to increase by 15.85%. Originality/value This study is the pioneer one, which is evaluating the intensity of farmers’ DMF adoption from adoption ratio, investment amount, labor input and adoption time. Additionally, the research provides important guidelines for policymakers to motivate medium and low-risk aversion farmers to adopt DMF.

Description: Purpose Worldwide, natural hazards are affecting urban cultural heritage and World Heritage Sites, exacerbating other environmental and human-induced threats deriving from deterioration, uncontrolled urbanization and unsustainable tourism. This paper aims to develop a disaster risk analysis in Italian historic centers because they are complex large-scale systems that are cultural and economic resources for the country, as well as fragile areas. Design/methodology/approach A heritage-oriented qualitative methodology for risk assessment is proposed based upon the formalization of risk as a function of hazard, vulnerability and exposure, taking into account the values of cultural heritage assets. Findings This work provides a contribution to the body of knowledge in the Italian context of disaster risk mitigation on World Heritage Sites, opening for further research on the monitoring and maintenance of the tangible heritage assets. The application to the site of San Gimignano proves the effectiveness of the methodology for proposing preventive measures and actions that ensure the preservation of cultural values and a safer built environment. Originality/value The application of a value-based simplified approach to risk analysis is a novelty for historic centers that are listed as World Heritage Sites.

Description: For parabolic Shilov equations with continuous coefficients, the problem of finding classical solutions that satisfy a modified initial condition with generalized data such as the Gelfand and Shilov distributions is considered. This condition arises in the approximate solution of parabolic problems inverse in time. It linearly combines the meaning of the solution at the initial and some intermediate points in time. The conditions for the correct solvability of this problem are clarified and the formula for its solution is found. Using the results obtained, the corresponding problems with impulse action were solved.

Description: PurposeThis study examines fisheries affected by the Great East Japan Earthquake and Tsunami in 2011 to explore how the collectivism appears during the recovery process.Design/methodology/approachThe author questions the context of collaboration after the disaster among independent small-scale fishers in Miyagi by conducting semistructured interviews with more than 50 local fishers with anthropological observations of boat fishing operations and using local documents and statistics.FindingsThe corresponding collaboration among the fishers after the disaster is not a mere “disaster utopia,” but is embedded in the socioecological context of fishing. Fishers have developed individual and group fishing. They have institutionalized competitive distribution for sedentary fish with low resource fluctuation, while outcome-equal distribution is adopted for migratory fish with high resource fluctuation. This forms a fishing continuum that connects competitive individualism with collectivism in the community, which has contributed to resilience for disaster recovery.Originality/valueThe balance between individualism and collectivism is decisively coordinated in socioecological contexts. The multifaceted resource strategy for maritime biodiversity that features family-based occupational differentiation in a community is crucial for disaster recovery of small-scale fishers.

Description: Purpose Legislation plays a vital role in solving carbon emissions reduction and climate change issues. China began to implement a low-carbon economic policy in 2010, but the effect of the policy needs to be evaluated. Accordingly, this paper aims to discuss China’s low-carbon policy through exploring the following two questions, namely, whether the policy effect reaches the expected goal and whether the policy effects will balance economic development and emission reduction. Then, the paper puts forward suggestions for the improvement of China’s low-carbon policy. Design/methodology/approach This paper is organized around three distinct aspects of policy effect evaluation. This paper uses the synthetic control method to construct a policy effect evaluation model and conducts a quasi-natural experiment. The paper selects annual panel data from 2003 to 2015, which is selected from 33 provinces. A comparative analysis of carbon dioxide emissions, energy consumption and economic development between Hubei Province and Liaoning Province. Findings The results reveal that the implementation of the low-carbon pilot province policy in 2010 has a significant impact on the emission reduction effect of Liaoning Province, but the impact on the emission reduction effect of Hubei Province is not significant. The carbon emission trading system implemented in 2012 has reduced the emission reductions in Hubei Province and Liaoning Province has achieved better emission reduction effects after the implementation of this policy. After the implementation of the policy, the economic development of Hubei Province has been improved, but it has not brought help to the economic development of Liaoning Province. These findings provide new insights into the use of an emissions trading system for improving economic development and ultimately facilitate the attainment of the broader goal of sustainability. Originality/value This paper proposes an innovative policy effect evaluation method by considering the status of unit gross domestic product, fixed asset investment in the energy industry, energy consumption, emission reduction technology innovation and other evaluation indicators. This paper contributes to broadening current methods of policy effect evaluation in China.

Description: Purpose This study aims to demonstrate the effectiveness of investment in flood protection by analyzing the flood disaster caused by Typhoon Hagibis in Japan in October 2019. The typhoon severely damaged the central and eastern Japan regions and threatened the Greater Tokyo area. Design/methodology/approach The paper examines flood risks in the Greater Tokyo area and reviews how the flood protection systems functioned to protect Tokyo from the typhoon. The hydrological data of rainfall and water levels at major rivers and the operation records of flood control facilities are collected and analyzed. Findings The study’s major finding is that the flood protection system succeeded in protecting the Greater Tokyo area from flooding. Typhoon Hagibis maintained its power until landing because of climate change and caused record-breaking rainfall. In a worst-case scenario, thousands of people could have died and hundreds of billions USD worth of assets could have been lost in Tokyo. Practical implications The paper describes the actual effects of the flood protection systems, consisting of dams constructed upstream, reservoirs midstream and diversion channels downstream. Thus, this study’s findings directly relate to practical implications for other countries and cities, which face flood risks under a changing climate. Originality/value The paper highlights the importance of investing in flood protection by examining actual disasters and providing detailed descriptions of flood protection systems.

Description: Combinatorial sums and binomial identities have appeared in many branches of mathematics, physics, and engineering. They can be established by many techniques, from generating functions to special series. Here, using a simple mathematical induction principle, we obtain a new combinatorial sum that involves ordinary powers, falling powers, and binomial coefficient at once. This way, and without the use of any complicated analytic technique, we obtain a result that already exists and a generalization of an identity derived from Sterling numbers of the second kind. Our formula is new, genuine, and several identities can be derived from it. The findings of this study can help for better understanding of the relation between ordinary and falling powers, which both play a very important role in discrete mathematics.

Description: Purpose Forestry carbon sink (FCS) is not only an important measure to deal with the current global climate change but also an effective way to build an ecological civilization. As an important form of implementation of FCS, the afforestation and reforestation projects under the clean development mechanism (CDM A/R) have important functions such as ecological protection and economic growth. This paper aims to evaluate the short-term and long-term impact of CDM on the county economy and its impact mechanism. Design/methodology/approach This paper first uses propensity score matching to match the county (treatment group). Second, this paper uses difference in difference to estimate the net effect of CDM A/R project on county economic development to reduce estimation error. Finally, the impact mechanism of implementing CDM A/R project on county economic development was tested. Findings The CDM A/R project has significantly promoted the development of real gross domestic product (GDP) and per capita real GDP in the region. Because of the long project cycle, this promotion is not immediate in the short term and has an obvious hysteresis effect. The longer the implementation time, the greater the promotion of the local economy will develop. The results are robust after the robustness test that uses the single-difference method. The CDM A/R project has promoted local economic growth by optimizing the local industrial structure, increasing the regional capital stock and raising the regional government’s fiscal revenue and expenditure. Originality/value This paper provides a critical overview of the relationship between clean development mechanism and local economic development.

Description: Purpose The concept of multi-purpose cyclone shelters has been found effective in saving various lives during past cyclones. The recent cyclone Amphan, which hit the Indian states of Odisha and West Bengal in the middle of pandemic COVID-19 has posed severe issues related to cyclone shelter management in the rural areas. The purpose of this paper is to investigate the case of Odisha in a pandemic and draw some key lessons of cyclone shelter management, which can be useful for future cascading risks in other parts of the country and the region. Design/methodology/approach Cyclone shelters are critical infrastructures in the management of cyclones, associated hazards and saving crucial lives. The effective management of shelters during emergencies is dependent on the existing institutional mechanism, local stakeholders and their understanding of the key functions of the emergency shelters. This paper reviews the key challenges through literature, reports and direct interviews of field professionals and practitioners. Findings In normal times, cyclone shelters are used as schools and their management lies with the local communities and/or elected bodies. Some of the key emerging issues include: the convincing population at risk for evacuation with proper care, existing emergency shelters being repurposed as COVID-19 facilities, need for hygiene and safety material, special arrangement and segregation of population at higher risk of COVID-19 and large destruction of social infrastructures. Originality/value During cascading disasters, adaptive governance becomes important. With the study of cyclones during the pandemic period, the paper draws key decision-making and governance points of cyclone shelter management. This case analysis can be useful to other similar situations during the prolonged pandemic time.

Description: Purpose In cities with high density, heat is often trapped between buildings which increases the frequency and intensity of heat events. Researchers have focused on developing strategies to mitigate the negative impacts of heat in cities. Adopting green infrastructure and cooling pavements are some of the many ways to promote thermal comfort against heat. The purpose of this study is to improve microclimate conditions and thermal comfort levels in high-density living conditions in Seoul, South Korea. Design/methodology/approach This study compares six design alternatives of an apartment complex with different paving and planting systems. It also examines the thermal outcome of the alternatives under normal and extreme heat conditions to suggest strategies to secure acceptable thermal comfort levels for the inhabitants. Each alternative is analyzed using ENVI-met, a software program that simulates microclimate conditions and thermal comfort features based on relationships among buildings, vegetation and pavements. Findings The results indicate that grass paving was more effective than stone paving in lowering air temperature and improving thermal comfort at the near-surface level. Coniferous trees were found to be more effective than broadleaf trees in reducing temperature. Thermal comfort levels were most improved when coniferous trees were planted in paired settings. Practical implications Landscape elements show promise for the improvement of thermal conditions because it is much easier to redesign landscape elements, such as paving or planting, than to change fixed urban elements like buildings and roads. The results identified the potential of landscape design for improving microclimate and thermal comfort in urban residential complexes. Originality/value The results contribute to the literature by examining the effect of tree species and layout on thermal comfort levels, which has been rarely investigated in previous studies.

Description: PurposeThe objective of this study was to investigate how participatory 3D mapping can promote local intergenerational engagement for disaster risk reduction.Design/methodology/approachThis investigation was carried out in the city of São Luiz do Paraitinga, Brazil, where a low-cost participatory 3D model (P3DM) was used together with secondary methods (semi-structured interviews, round tables, discussions and presentations) to engage three local focus groups (the general public, high school employees and children) to visualize and interpret local hazards, vulnerabilities, capacities and risk mitigation measures.FindingsParticipants played with a 3D model, using it to express their memories about land use changes in the city and to share their knowledge about past disasters with children that have not faced them. They identified the impacts of the previous disasters and came up with proposals of risk mitigation measures, mostly non-structural.Originality/valueWhen applied in a way that allows spontaneous and open public participation, the participatory 3D model can be a type of disaster imagination game that gives voice to oral histories, local knowledge, and which permits the intergenerational engagement for disaster risk reduction.

Description: Purpose The paper deals with the challenges and opportunities of enabling resilience of the built environment through building regulations and codes in a developing country context. The purpose of this paper is to explore how voluntary compliance can be achieved, drawing from the views of key stakeholders in this field. Design/methodology/approach Dhaka, the capital city of Bangladesh, is a central hub of more than 20 million people. The city is growing rapidly in an unplanned manner to host the increasing population, creating vulnerability to different hazards including earthquakes, fires and building collapses. The Bangladesh National Building Code (BNBC) and the building and planning regulations of the Capital Development Authority are the key instruments for ensuring safety, but lack of compliance is widespread. The views of relevant stakeholders on issues relating to compliance of safe building codes for ensuring disaster resilience were documented and analysed. Findings It was found that those involved in construction activities are in most cases not aware of the BNBC; landowners were reluctant to follow regulations and codes to avoid extra cost; and construction workers were not interested in compliance as there were no incentives. While enforced deterrence is required, it has its limitations in a context such as Dhaka. Raising awareness and building capacity at all levels can offer a way forward for voluntary compliance. Incorporation of knowledge on regulations and codes for disaster resilience into university and technical education curricula are likely to allow developing the capacity of built environment professionals and widespread awareness can be raised through training, media and public events. Originality/value There are many publications on building regulations and codes, but few specifically focussing on disaster resilience. Also, much of the discussion on regulations and codes deals with compliance through enforcement, but hardly any deal with the idea of voluntary compliance. There are also a lot of publications on disasters in the case study city, Dhaka, but comparatively few on building codes and regulations specifically for disaster resilience.

Description: A graph G is called cycle books B 4 , m , 2 if G consists of m cycles C 4 with a common path P 2 . Figueroa-Centeno, Ichishima, and Muntaner-Batle conjecture that the graph B 4 , m , 2 is super edge-magic total if and only if m is even or m ≡ 5   mod 8 . In this article, we prove this conjecture for m  ≥ 36 and m  = 0 mod (2).

Description: Purpose Several post-disaster housing extension and modification studies have indicated that owner-driven modification behavior relates to socio-economic and livelihood factors. This study aims to clarify housing extension patterns and examine the relationships among spatial characteristics, sociocultural factors, livelihood factors and housing extensions. This research also highlights the implications of post-disaster housing design for indigenous communities. Design/methodology/approach An indigenous community case study was conducted using a literature review. Moreover, interview surveys and housing measurements were implemented based on purposive sampling to diversify interviewees’ backgrounds and the extent of housing extensions. Findings This study confirms that housing extensions are closely related to the number of household members and their associated functions and cultural and livelihood factors that were ignored during the design stage. Furthermore, the housing extension process was confirmed to match households’ economic recovery. A post-disaster housing implementation framework for the indigenous population is proposed. Research limitations/implications This research only targeted one indigenous community with a limited number of interviewees and samples because of the connection with households. Practical implications The study’s proposed resilience post-disaster housing framework can be used to develop post-disaster housing design guidelines, which can benefit policymaking. The proposed participatory concept can be further adopted in future disaster risk-reduction programs. Originality/value This study uniquely focuses on the pre- and post-disaster housing layout and the livelihood of an indigenous community. It offers valuable insights for post-disaster reconstruction planners and practitioners.

Description: A mapping   ℸ :   V G ⟶ N ∪ 0 for a connected graph G = V , E is called a radial radio labelling if it satisfies the inequality     ℸ x −   ℸ   y + d x , y ≥ rad G + 1 ∀ x , y ∈ V G , where rad G is the radius of the graph G . The radial radio number of ℸ denoted by r r ℸ   is the maximum number mapped under ℸ . The radial radio number of G denoted by r r G is equal to min { r r ℸ   / ℸ   is a radial radio labelling of G }.

Description: Purpose The purpose of this paper is to statistically assess the effects of the design factors including usage of data-driven decision support tool (DST), classification of patients (triage), prioritization based on vital scores of patients, number of ambulances and hospital selection rules, on the casualty transportation system’s performance in large-scale disasters. Besides, a data-driven DST for casualty transportation is proposed to enhance the casualty survival and ambulance transportation times during the disaster response stage. Design/methodology/approach In this study, the authors applied simulation and statistical analysis to evaluate the effects of usage of data-driven DST, classification of patients (triage), prioritization of the patients based on vital scores, number of ambulances and hospital selection rules, on the patient survival and transportation time of the casualty transportation system. An experimental design was made, and 16 scenarios were formulated. Simulation models were developed for all scenarios. The number of unrecoverable casualties and time-spent by the casualties until arriving at the hospital was observed. Then, a statistical analysis was applied to the simulation results, and significant factors were determined. Findings Utilization of the proposed DST was found to improve the casualty transportation and coordination performance. All main effects of the design factors were found statistically significant for the number of unrecoverable casualties. Besides, for the Time spent Until Arrival of T1-Type Casualty at the Hospital, all of the main factors are significant except the number of ambulances. Respiratory rate, pulse rate, motor response score priority and hospital selection rule based on available hospital capacities must be considered to reduce the number of unrecoverable casualties and time spent until arrival of the casualties at the hospitals. Originality/value In this study, the factors that significantly affect the performance of the casualty transportation system were revealed, by simulation and statistical analysis, based on an expected earthquake case, in a metropolitan city. Besides, it was shown that using a data-driven DST that tracks victims and intends to support disaster coordination centers and medical staff performing casualty transportation significantly improves survival rate of the victims and time to deliver the casualties. This research considers the whole systems’ components, contributes to developing the response stage operations by filling gaps between using the data-driven DST and casualty transportation processes.

Description: Purpose This study aims to assess gender-based differences on farmers’ perception of impacts and vulnerability to climate change and the implementation of adaptation strategies in the Pra River Basin of Ghana, while also providing lessons for other Sub-Saharan nations and regions with similar conditions. Design/methodology/approach The study used semi-structured interviews and questionnaires to collect data from 344 farmers, 64 participants in focus group discussions and 6 agriculture extension officers (key informants) from 10 districts in the Pra River Basin of Ghana. Findings Results showed several differences in how climate change is perceived and tackled by male and female genders. In the perception of male farmers, for example, they were found to be more vulnerable to increased temperature, and changes in rainfall and growing season, whereas female farmers on average were considered to be less resilient to floods and droughts for different reasons. Moreover, floods posed higher risks to farming than other climate change impacts. Gender roles had a significant correlation with the type of adaptation strategies practised. Men adopted agrochemicals more often than women, as an adaptation strategy. Research limitations/implications Gender-differentiated interventions should be incorporated in the national climate change action plan for sustainable development in a rain-fed agricultural economy such as Ghana. The study recommends several actions to promote gender equity in the assessed region. Originality/value This research assessed the gender differentials in climate trends, impact, vulnerability and adaptation based on primary data collected between April and May 2019 and compared the results with climate data in the basin for the period 1991–2014. It is an empirical study focused on primary data analysis obtained in loco by authors, involving approximately 400 participants.

Description: Purpose In recent years, agricultural activities in the Mekong Delta have frequently faced the potential risks of drought, saline intrusion and unusually heavy rainfall because of climate change, leading to a decline in crop yield. Therefore, this study aimed to establish rice planting seasons in An Giang, an upper-located province in the Mekong Delta. Design/methodology/approach The impacts of seasonal variation on the key rice seasons were simulated using the Food and Agriculture Organization-crop model for the OM6976 rice variety grown in the study area. For the simulation, the model combined crop, soil, weather and crop management data. Findings The results show that seasonal variation because of changes in weather factors leads to alternation in crop yields across the study area. Specifically, the spring and summer rice planting seasons are advanced by one to two weeks compared with the baseline, and crop yield increased by 5.9% and 4.2%, respectively. Additionally, planting for the autumn–winter rice season on 3 August increased crop yield by up to 8.1%. Originality/value In general, rice planting seasons that account for weather factor changes effectively reduce production costs and optimise production.

Description: Purpose The purpose of this paper is to improve the conceptual understanding of the process of participation in early warning systems (EWS) through a review of participatory EWS examples in the academic literature. Specifically, this paper asks: who is involved, what responsibilities do participants hold, what activities are they involved in, and what are the associated successes, issues and outcomes? Design/methodology/approach A total of 30 cases of participation in EWS documented in the academic literature were identified through online searches. Existing concepts in participation (power and responsibility, communication) and people-centred early warning (risk knowledge, monitoring and warning, communication and dissemination and response capability) were used to examine each paper. Findings Participation was found to take place through a range of activities across all elements of the EWS. Participation also varied in breadth of inclusion, ranging from the general public to selected volunteers. The majority of cases received support and facilitation from other actors, such as government and NGOs, but the extent of power and responsibility held by participants varied greatly within this. Common successes and issues associated with participatory EWS and the potential outcomes are presented, and the opportunities, challenges and gaps in knowledge are discussed. Originality/value This paper links participation and EWS literature to form a clearer conceptualisation of participation in EWS in support of future research in the field. It provides unique insights into who participates, their roles and relations with other actors and the outcomes of participation.

Description: Purpose Higher education plays a vital role in educating citizens about climate change and promoting pro-environment behavior. Based on this statement, this study aims to analyze and evaluate students’ perception of climate change at the University of the South Pacific in Fiji. The study aims to understand the main ideas and concepts of climate change by analyzing information habits and individual opinions on the causes of climate change as perceived by the students of two student organizations aimed at environmental protection. Design/methodology/approach A qualitative approach was used to gather data on students’ perceptions and information habits toward climate change. The data were collected through a questionnaire to characterize students from the socio-demography and their perceptions, information habits and knowledge relating to climate change. This paper uses the case study method to examine students’ climate change perceptions at two different student organizations at the same university. The research study involved a focus group technique. Two focus groups at the University of the South Pacific were administered. The focus groups’ selection in this study took into account the aims and objectives of the students’ organization toward climate change awareness, adaptation, mitigation and environment protection. Findings The focus groups participants believe that climate change is a serious problem in the South Pacific region. Results suggest significant differences in climate change perception at the two students’ organizations chosen for this study. Students at the Econesian society nicknamed climate change as a nuclear weapon for the South Pacific responsible for changes in the habitat, coral bleaching, lifestyle changes, mother of all other environmental problems and the introduction of invasive species into Fiji. Students at Wantok Moana-related climate change to drastic weather changes, lack of fish feed and additional toxins in the sea. The results also showed that students at the Econesian society have a better understanding of climate change than the students of Wantok Moana. Practical implications This paper provides an insight into how students of Small Islands Developing States view climate change and the factors affecting their opinions. It also shows how climate change perception varies within the same university. This implies the need to integrate climate change into the higher education curriculum and more research on this topic. Originality/value This paper is the first to compare and contrast university students’ climate change perception in Fiji. The results make an essential contribution to the extant climate change literature by identifying and categorizing climate change perception and the factors that shape students’ perception of climate change from the university students’ perspective in Fiji.

Description: Purpose The purpose of this paper was to assess the effects of quality coffee production on climate change adaptation using household surveys and interview data gathered from coffee farmers in Yirgacheffe, southern Ethiopia. Design/methodology/approach A sample of 352 households, stratified into conventional coffee farmers 232 (66%) and specialty coffee producers 120(34%), was used. The propensity score model for participating in quality coffee production was estimated using 14 covariates, and the impact of quality coffee production on adaptation to climate change adaptation was examined. The results are augmented with qualitative data collected through focus group discussions and key informant interviews held with randomly selected smallholder farmers. A telecoupling theoretical perspective was used to understand the link between coffee farmers’ adaptation practices and the demand for quality coffee, as coffee is a global commodity. Findings The PSM analysis reveals that quality coffee production positively influences climate change adaptation. This implies that conventional coffee producers would have performed better in adaptation to climate change if they had participated in quality coffee production. The results of group discussions also confirm the positive effects of quality coffee production on adaptation to climate change, which also suggests a positive spillover effects for sustainable coffee farm management. Practical implications This study suggests enhancing quality coffee production is essential if a more sustainable and climate change resilient coffee livelihood is envisioned. Originality/value Though many studies are available on adaptation to climate change in general, this study is one of the few studies focusing on the effects of quality coffee production on climate change adaptation by smallholders in one of the least developed countries, Ethiopia. This study provides a better understanding of the importance of adaptation strategies specific to coffee production, which in turn help develop a more resilient coffee sector, as coffee production is one of the most sensitive activity to climate change.

Description: Purpose Smallholder farmers have always been profoundly the first to be impacted by climate change, and therefore, farmers understanding of climate change and accessibility to alternative adaptation strategies are crucial for reducing the effect of climate change. The purpose of this study is to assess the perception of farmers to climate change, adaptation strategies and determinants of adaptation choice in central Ethiopia. Design/methodology/approach The study used data from randomly selected 240 farm households. Descriptive statistics were used to describe farmers’ perceptions of climate change and adaptation strategies. Also, a multivariate probit model was used to identify the major factors affecting farmers’ choice of adaptation strategies to climate change in central Ethiopia. Findings Smallholder farmers perceive climate change in the past two decades in response; the majority (91.47%) of farmers used adaptation options. Improved crop varieties and input intensity, crop diversification, planting date adjustment, soil and water conservation activities and changing of the crop type were used as adaptation options in the study area. A few of these strategies were significantly confirmed a complementary and supplementary relationship. The study identified sex, family size, agroecology, climate information, crop-fail history and formal extension service as significant determinants for farmers’ adaptation choices as these variables significantly affected more than two farmers’ adaptation strategies simultaneously. Research limitations/implications Farmers’ choice of adaptation was highly constrained by institutional factors and all these identified factors can be possibly addressed through a better institutional service provision system. It is, therefore, recommended that local administrators should explore the institutional service provision system for a better farm-level adaptation while considering demographic characteristics as well. Originality/value This study identified factors affecting farmers’ several adaptation strategies at a time and provides information for the policymaker to make cost-effective interventions for better farm-level adaptation practices.

Description: For a polynomial p z of degree n , it follows from the maximum modulus theorem that max z = R ≥ 1 p z ≤ R n max z = 1 p z . It was shown by Ankeny and Rivlin that if p z ≠ 0 for z

Description: In this paper, we introduce a new class of contact pseudo framed (CPF)-manifolds M , g , f , λ , ξ by a real tensor field f of type 1,1 , a real function λ such that f 3 = λ 2 f where ξ is its characteristic vector field. We prove in our main Theorem 2 that M admits a closed 2-form Ω if λ is constant. In 1976, Blair proved that the vector field ξ of a normal contact manifold is Killing. Contrary to this, we have shown in Theorem 2 that, in general, ξ of a normal CPF-manifold is non-Killing. We also have established a link of CPF-hypersurfaces with curvature, affine, conformal collineations symmetries, and almost Ricci soliton manifolds, supported by three applications. Contrary to the odd-dimensional contact manifolds, we construct several examples of even- and odd-dimensional semi-Riemannian and lightlike CPF-manifolds and propose two problems for further consideration.

Description: In this article, we present an approach which allows taking into account the effect of extreme values in the modeling of financial asset returns and in the valorisation of associated options. Specifically, the marginal distribution of asset returns is modelled by a mixture of two Gaussian distributions. Moreover, we model the joint dependence structure of the returns using a copula function, the extremal one, which is suitable for our financial data, particularly the extreme values copulas. Applications are made on the Atos and Dassault Systems actions of the CAC40 index. Monte Carlo method is used to compute the values of some equity options such as the call on maximum, the call on minimum, the digital option, and the spreads option with the basket (Atos, Dassault systems) as underlying.

Description: PurposeFrom a Latin American decolonial and transdisciplinary perspective, this article expands the increasingly relevant conversation about disaster ethics, not only in depth and scope but also both interdisciplinarily and interculturally. By reviewing key points of development ethics that are closely related but underexplored, it makes the case for focusing on disaster recovery as a relevant distributive phase for improving future prevention and mitigation, while remedying long-standing injustices.Design/methodology/approachTo do so, against the backdrop of recently emerging postcolonial, decolonial and structural approaches to disaster and vulnerability studies, the article presents a theoretical conversation between decolonial studies, development ethics, intercultural practice and philosophy, and disaster ethics beyond utilitarian approaches.FindingsSo far, development and disaster ethics remain worlds apart, despite their relevant convergence around the key notion of “recovery” and its underlying normative determination. This article identifies that prevailing utilitarian ethics in emergency response, in addition to their problematic universalization, have prevented further engagement with deontological and process-based principles, including a nuanced distributive sensitivity. As a result of such cross-fertilization, methodological individualism in an intercultural encounter is suggested, as well as continued engagement with pluriversal deliberation about key ethical values and notions regarding disaster risk and response.Originality/valueCalling for distributive bottom-up engagement beyond professional and academic boundaries, this article presents a new direction for decolonising disaster ethics, so far unexplored, seeking to bridge the value gap between development and disaster efforts, planning and prevention.

Description: This paper presents a new approach to determine the number of solutions of three-variable Frobenius-related problems and to find their solutions by using order reducing methods. Here, the order of a Frobenius-related problem means the number of variables appearing in the problem. We present two types of order reduction methods that can be applied to the problem of finding all nonnegative solutions of three-variable Frobenius-related problems. The first method is used to reduce the equation of order three from a three-variable Frobenius-related problem to be a system of equations with two fixed variables. The second method reduces the equation of order three into three equations of order two, for which an algorithm is designed with an interesting open problem on solutions left as a conjecture.

Description: In this paper, we present and establish a new result on the stability analysis of solutions for fuzzy nonlinear fractional differential equations by extending Lyapunov’s direct method from the fuzzy ordinary case to the fuzzy fractional case. As an application, several examples are presented to illustrate the proposed stability result.

Description: Proposed in 1937, the Collatz conjecture has remained in the spotlight for mathematicians and computer scientists alike due to its simple proposal, yet intractable proof. In this paper, we propose several novel theorems, corollaries, and algorithms that explore relationships and properties between the natural numbers, their peak values, and the conjecture. These contributions primarily analyze the number of Collatz iterations it takes for a given integer to reach 1 or a number less than itself, or the relationship between a starting number and its peak value.

Description: This article deals with the study of mathematical models and the assessment of the stability of the motion of ships, investigating properties of the system such as kinetics and stability. This is essential for the selection of suitable control methods according to the requirements set out for the problem. Some control methods require the author to specify control parameters before the operation of the system can be started. Therefore, the survey of the article is useful for the above problem. Control methods through simulation results (PID controller, lag compensator, and lead compensator) give me results that reflect properties of the system (the stability of the operation cycle of the ship model). In addition, control methods for this model, which serve for research and education, are also presented below. Simulation is done by Matlab.

Description: PurposeThis paper is joint reflection on the role of research assistants (RAs) in fieldwork for disaster risk research, particularly at the doctoral level. The paper has been co-authored by Gurung, who worked as a RA with the other author McGowran during his doctoral field research in Kalimpong from May 2019 to January 2020. The piece allows Gurung to voice his ideas on the research in a published research output and allows both authors to reflect on how the collaborative approach taken helped to make the research more responsive to, and reflective of, the problems people affected by landslides in Kalimpong face. The paper aims to highlight the benefits of working with RAs on landslide prevention and management in areas that may be unfamiliar and to provide a space for the RAs to voice their opinion on the research.Design/methodology/approachThe paper is split into sections written by and in the voice of the authors. This reflects a compromise between wanting Gurung's voice to be clearly heard in the piece and the challenges of non-academically trained RAs contributing to academic outputs that require specific training. Brief outlines of Kalimpong district disaster research in the region are set out by McGowran initially. Gurung then outlines how he became involved in the research and how this affected the research methodology. He reflects on how the research played out and presents some brief reflections on the findings. McGowran then concludes the piece.FindingsThe authors discuss how landslides in Kalimpong are related to locally specific political, economic, cultural and physical processes. It is only through discussing these processes with the people who live with and are affected by these landslides that this more holistic understanding can be gained, even though complete explanations are never usually found. Ideas for further research into landslides in Kalimpong and elsewhere are presented, centering on the involvement of people affected by disasters in this research.Originality/valueThe authors hope the publication of the paper might set more of a precedent for the voice of RAs – and those who are affected by disasters – to be more clearly heard in disaster risk research and practice in future. More of this type of research could help to address some of the issues this special issue raises.

Description: Purpose Quantitative and spatial-explicit flood risk information is of great importance for strengthening climate change adaptation and flood resilience. Shanghai is a coastal megacity at large estuary delta with rising flood risks. This study aims to quantify the overall economic-societal risks of storm flooding and their spatial patterns in Shanghai. Design/methodology/approach Based on multiple storm flood scenarios at different return periods, as well as fine-scale data sets including gridded GDP, gridded population and vector land-use, a probabilistic risk model incorporating geographic information system is used to assess the economic-societal risks of flooding and their spatial distributions. Findings Our results show that, from 1/200 to 1/5,000-year floods, the exposed assets will increase from USD 85.4bn to USD 657.6bn, and the direct economic losses will increase from USD 3.06bn to USD 52bn. The expected annual damage (EAD) of assets is around USD 84.36m. Hotpots of EAD are mainly distributed in the city center, the depressions along the upper Huangpu River in the southwest, the north coast of Hangzhou Bay, and the confluence of the Huangpu River and Yangtze River in the northeast. From 1/200 to 1/5,000-year floods, the exposed population will rise from 280 thousand to 2,420 thousand, and the estimated casualties will rise from 299 to 1,045. The expected annual casualties (EAC) are around 2.28. Hotspots of casualties are generally consistent with those of EAD. Originality/value In contrast to previous studies that focus on a single flood scenario or a particular type of flood exposure/risk in Shanghai, the findings contribute to an understanding of overall flood risks and their spatial patterns, which have significant implications for cost-benefit analysis of flood resilience strategies.

Description: The study recognized the worth of understanding the how’s of handling censoring and censored data in survival analysis and the potential biases it might cause if researchers fail to identify and handle the concepts with utmost care. We systematically reviewed the concepts of censoring and how researchers have handled censored data and brought all the ideas under one umbrella. The review was done on articles written in the English language spanning from the late fifties to the present time. We googled through NCBI, PubMed, Google scholar and other websites and identified theories and publications on the research topic. Revelation was that censoring has the potential of biasing results and reducing the statistical power of analyses if not handled with the appropriate techniques it requires. We also found that, besides the four main approaches (complete-data analysis method; imputation approach; dichotomizing the data; the likelihood-based approach) to handling censored data, there were several other innovative approaches to handling censored data. These methods include censored network estimation; conditional mean imputation method; inverse probability of censoring weighting; maximum likelihood estimation; Buckley-Janes least squares algorithm; simple multiple imputation strategy; filter algorithm; Bayesian framework; β -substitution method; search-and-score-hill-climbing algorithm and constraint-based conditional independence algorithm; frequentist; Markov chain Monte Carlo for imputed data; quantile regression; random effects hierarchical Cox proportional hazards; Lin’s Concordance Correlation Coefficient; classical maximum likelihood estimate. We infer that the presence of incomplete information about subjects does not necessarily mean that such information must be discarded, rather they must be incorporated into the study for they might carry certain relevant information that holds the key to the understanding of the research. We anticipate that through this review, researchers will develop a deeper understanding of this concept in survival analysis and select the appropriate statistical procedures for such studies devoid of biases.

Description: Purpose The current National Early Warning System for Sri Lanka (NEWS: SL) was established after the devastations of the Indian Ocean Tsunami in 2004. Although early warning (EW) systems and evacuation procedures are in place, several areas which need improvements have been emphasized in recent studies carried out in the country. Therefore, this paper aims to outline the gaps in existing EW and EP related to tsunami and other coastal hazards with a special focus on the use of social media for disaster communication based on age groups. Design/methodology/approach This study has drawn on a review of past studies carried out by the same research team to identify the scope of the study. In addition to that, a conceptual framework was developed for the use of social media in the event of a disaster. Based on this conceptual framework, an online questionnaire was administered to identify the current status of the use of social media in Sri Lanka during a disaster situation. In total, 408 responses were collected and analyzed using the binary logistic regression method to evaluate the variation of different predictors associated with the use of social media for disaster communication. Findings Findings of the study revealed that the use of social media for disaster communication depends on the previous experience of users and their age. The gender of users does not affect the use of social media for disaster communication. Therefore, the accuracy and timeliness of disaster information distributed via social media should be improved further to enhance the use of social media for disaster communication. Moreover, the findings have highlighted unaddressed issues in areas such as governance; communication of technical agencies; evacuation and shelters; and response of the community. Originality/value This paper has identified key areas that need attention in the process of enhancing the use of social media for disaster communication. More use of technological platforms such as social media for receiving disaster-related information can address issues such as bottlenecks in communication, poor awareness and lack of last-mile dissemination. Furthermore, this paper has proposed recommendations for addressing the identified gaps in the overall EW mechanisms and EP pertaining to tsunamis and other coastal hazards to enhance the coastal disaster resilience in Sri Lanka.

Description: Purpose This paper aims to examine adaptive livelihood strategies used by small-scale fishing households in the two coastal communities in Central Vietnam under the context of climate change-related stressors. Design/methodology/approach Field data were collected through mixed quantitative and qualitative methods including a review of secondary data, key-informant interviews, group discussions and household surveys with 300 sampled fishing households. The qualitative data support the analysis and discussion of quantitative data. Findings The results showed local households’ perception of the presence and influence of multiple non-climate and climate stressors on their fishery-based livelihoods in terms of employment and income in many ways. The affected households exerted to develop a diversity of adaptation methods within and out of fishing to sustain their livelihoods and cover a deficit in household income. The household socio-demographic characteristics particularly education, labour force, fishing equipment and social support played significant importance in characterising the categories of adaptation strategies among the survey households. The role of local governments in creating an enabling environment for local-level adaptation, as well as protecting marine and coastal ecosystems was rather limited despite their recognized importance. Originality/value The paper provides an empirical case of how small-scale fishing households in coastal communities in Central Vietnam are adapting to climate-related stressors. It suggests policy should promote livelihood diversification opportunities and address household-level constraints for adaptation. Fisheries management plan is urgently needed to control illegal fishing activities for sustainable use of coastal and marine fishery resources and the appropriate mechanism is important to stretch local governments’ resources for better supporting local-level adaptation.

Description: PurposeBased on the research, the authors identify how four key concepts in disaster studies—agency, local scale, memory and vulnerability—are interrupted, and how these interruptions offer new perspectives for doing disaster research from and for the South.Design/methodology/approachMeta-analysis of case studies and revision of past and current collaborations of authors with communities across Chile.FindingsThe findings suggest that agency, local scale, memory and vulnerability, as fundamental concepts for disaster risk reduction (DRR) theory and practice, need to allow for ambivalences, ironies, granularization and further materializations. The authors identify these characteristics as the conditions that emerge when doing disaster research from within the disaster itself, perhaps the critical condition of what is usually known as the South.Originality/valueThe authors contribute to a reflexive assessment of fundamental concepts for critical disaster studies. The authors offer research-based and empirically rich redefinitions of these concepts. The authors also offer a novel understanding of the political and epistemological conditions of the “South” as both a geography and a project.

Description: We extend the well-known characterizations of convergence in the spaces l p ( 1 ≤ p

Description: Purpose This study examines the websites of central government ministries, prefectures and municipalities to obtain a comprehensive bird’s-eye view of how they are preparing for natural disasters in the context of the novel coronavirus (COVID-19) outbreak. Design/methodology/approach This study examines the websites of central government ministries, prefectures and municipalities in Japan to survey the actual status of information dissemination on “evacuation and sheltering” in the context of COVID-19. Findings This study found that the central government issued many notices, notifications and administrative communications to prefectures, cities with public health centers and special wards, which were mainly related to opening, securing and operating evacuation centers and improving the environment. It was found that most prefectures disseminated information on both survival and living evacuation and did so from June onward, when the flood season was approaching. Among the municipalities, there were differences in information dissemination tendencies by prefecture, and it became clear that smaller municipalities were especially incapable of fully disseminating information via the Web. Research limitations/implications The data from the prefectures and municipalities surveyed in this study were collected from websites and do not necessarily represent the actual response to disaster-related evacuation in the context of COVID-19 in those areas. To clarify this evacuation, more detailed surveys are needed. Originality/value This study is unique because no research has been conducted on the response of Japanese administrative agencies to disaster-related evacuation in the context of COVID-19; the actual situation was analyzed in this study by examining central government ministries, prefectures and municipalities as administrative agencies and comparing their responses.

Description: In this paper, we are interested in the inverse problem of the determination of the unknown part ∂ Ω , Γ 0 of the boundary of a uniformly Lipschitzian domain Ω included in ℝ N from the measurement of the normal derivative ∂ n v on suitable part Γ 0 of its boundary, where v is the solution of the wave equation ∂ t t v x , t − Δ v x , t + p x v x = 0 in Ω × 0 , T and given Dirichlet boundary data. We use shape optimization tools to retrieve the boundary part Γ of ∂ Ω . From necessary conditions, we estimate a Lagrange multiplier k Ω which appears by derivation with respect to the domain. By maximum principle theory for hyperbolic equations and under geometrical assumptions, we prove a uniqueness result of our inverse problem. The Lipschitz stability is established by increasing of the energy of the system. Some numerical simulations are made to illustrate the optimal shape.

Description: PurposeThis study aims to assess knowledge retention of the graduates of the online graduate certificate on local development planning, land use management and disaster risk management (PDLOTGR, the abbreviation of the certificate's Spanish title). The certificate was offered to practitioners and faculty members of Latin American countries since 2016.Design/methodology/approachThe authors reviewed the knowledge, attitude and practice (KAP) method to develop a specific approach, which included the preparation of a KAP survey, a composite KAP index and three sub-indices. The survey targeted two groups: (1) experimental group, composed of the certificate's 76 graduates, and (2) control group, comprised of 25 certificate's candidates, who had not yet undergone the training/intervention. The statistical analysis included a one-way multivariate analysis of variance to compare the mean scores on the KAP index and sub-indices for individuals in the experimental and control groups.FindingsThe study results showed significant differences in the knowledge sub-index between those who had completed the PDLOTGR training and those who had not, while the attitudes and practices sub-indices did not show significant differences. When using the KAP index, a statistically significant difference was also observed between the two groups.Originality/valuePerceived knowledge assessment offers an acceptable and non-intimidating option for evaluating continuing education and professional development programs associated to disaster risk. It is particularly helpful in determining whether an intervention or program has a lasting impact. It is not, however, a substitute for direct knowledge assessment, and the use of other methods to evaluate the performance of a capacity building program's graduates.

Description: PurposeThis paper aims to explore the involvement of various actors in the preparation of Palu City's spatial plan before the multi-hazard events of 2018. In addition, it evaluates the extent to which disaster risk reduction (DRR) is mainstreamed in the spatial plan.Design/methodology/approachThe study uses qualitative methods of analysis with a risk-based planning approach and stakeholder analysis.FindingsIt is critical that DRR is mainstreamed in spatial planning from the preparation to the implementation. Disasters can take place when there is a knowledge gap in the planning process. This results in developments in disaster-prone areas and even in high-risk areas. Therefore, mainstreaming DRR into spatial planning requires national guidelines that offer planners at the local level clear and detailed guidance on what they must prepare, consider and do in a risk-based spatial planning process.Practical implicationsSpatial planning that does not mainstream DRR can lead to catastrophic consequences in the form of casualties and losses when multi-hazards occur.Originality/valueThe study provides evidence-based findings on the importance of mainstreaming DRR into spatial planning, particularly in areas prone to multi-hazards, which can be optimized through a risk-based planning approach.

Description: PurposeThe way that disasters are managed, or indeed mis-managed, is often represented diagrammatically as a “disaster cycle”. The cyclical aspects of the disaster (risk) management concept, comprised of numerous operational phases, have, in recent years, been criticised for conceptualising and representing disasters in an overly simplistic way that typically starts with a disaster “event” – and subsequently leads onto yet another disaster. Such cyclical thinking has been proven to not be very useful for the complexities associated with understanding disasters and their risks. This paper aims to present an alternative conceptualisation of the Disaster Risk Management phases, in a way that can better factor in the underlying root causes that create differential levels of vulnerability.Design/methodology/approachThis is a conceptual paper developed, through a review of the literature and discussions between the authors, as a counterpoint to the pervasive “disaster cycle”.FindingsThe “Disaster Risk Management (DRM) Helix” is presented as an alternative way of conceptualising the DRM phases. The helictical conceptualisation of DRM phases presented in this paper is intentionally presented to start a discussion (rather than as an end point) on how best to move away from the constraints of the “disaster cycle”.Originality/valueIt is envisaged that the helictical conceptualisation of DRM can be suitably malleable to include important factors such as temporal considerations and the underlying root causes that create differential levels of vulnerability. It is, thus, the intention that the DRM Helix can provide a catalyst for exciting discussions and future adaptations of the diagram that can better capture the dynamic (non-cyclical) nature of disasters and their root causes.

Description: Purpose This paper aims to understand the perception of smallholder farmers on climate change, identify major livestock related climate change adaptation (CCA) strategies and their determinants in selected neighboring districts of Tigray and Amhara regions of Ethiopia. Design/methodology/approach A total of 416 household heads were involved in a questionnaire survey using a multistage sampling approach. To understand the socio-economic factors that influence farmers’ perception on climate change (CC) and/or variability, a binary logit model was used. Multinomial logit model was used to identify the determinants of smallholder farmers’ choices of adaptation strategies. Findings Milk reduction, weight loss, feed shortage and frequent animal disease outbreak were indicated as major impacts of CC on livestock production. About 86.2% of the farmers’ exercise CCA measures where livestock health care and management (25%), followed by livelihood diversification (21.5%) and shifting and diversification of livestock species (20.9%) were the top three adaptation measures implemented. Education, knowledge on CCA strategies, access to veterinary service and extension, market access, annual income, non-farm income, total livestock unit, sex of household head and household size were the major determinant factors to farmers’ choice of CCA. Research limitations/implications Concerned authorities working in CC related sectors should give due attention to improve smallholder farmers’ access to extension and veterinary services, market access and climate information to enhance their adaptive capacity to CC impacts. In addition, incorporating climate change awareness trainings into the existing extension packages is crucial to enhance the awareness of farmers on climate change and implement appropriate adaptation strategies. Moreover, it is very essential to provide appropriate herd management and marketing strategy based on the production system to avoid the significant price reduction during drought periods. Practical implications Concerned authorities working in CC related sectors should give due attention to improve smallholder farmers’ access to extension and veterinary services, market access and climate information to enhance their adaptive capacity to CC impacts. In addition, incorporating climate change awareness trainings into the existing extension packages is crucial to implement appropriate adaptation strategies. Moreover, it is very essential to provide appropriate herd management and marketing strategy based on the production system to avoid the significant price reduction during drought periods. Originality/value This research is focused on smallholder crop-livestock farmers, livestock-based CCASs and presents the determinant factors to their choice of adaptation.

Description: Purpose Nowadays, nearly the whole globe is confronting a severe threat of the COVID-19. The purpose of this paper is to explore the predictors of environmental concerns during the COVID-19 among the entrepreneurs during a second pandemic wave. Design/methodology/approach The deductive approach is applied based on cross-sectional data. An online response is gotten from entrepreneurs of Pakistan. A convenience sampling is applied to target the entrepreneurs. In total, 220 usable answers ensue for the outcome. The structural equation model (SEM) is used for the assessment of hypotheses. Findings The results of this study highlight a significant and positive effect of uncertainty of COVID-19 (U19), Perceived vulnerability (PV), Risk perception of COVID-19 (RP) and Fear of COVID-19 (F19) on environmental concerns (EC) among the entrepreneurs. Practical implications The research outcomes would provide the guidelines to policymakers and planners to develop the policies for reducing the fear, vulnerability, risk and uncertainties during the waves of the COVID-19. The findings of the study would make disaster resilience which COVID-19 creates. The results would provide the re-built environment guidelines by reducing fear, vulnerability, risk and uncertainties. Besides, the findings would help provide the knowledge and practical aspects of disasters in terms of anxiety, exposure, risk and uncertainties, which are hazardous for humans and the environment. Originality/value This study provides the empirical evidence which is the first time conducted among the entrepreneurs. Besides, this study highlights the predictors such as fear, vulnerability, risk and uncertainties towards EC in the COVID-19 scenario.

Description: PurposeResilience has become a priority of most agendas for disaster risk reduction at different scales leading to an increase demand for measurement of resilience. However, resilience is mostly defined, assessed and measured by outsider experts rather than by those primarily concerned – local people. This article presents the development of people-centred indicators of resilience in New Zealand. It details both the process and outcomes of these indicators.Design/methodology/approachThe study draws from participatory methods to develop a six-step tool kit for people-centred indicators of resilience. The people-centred indicators were implemented with four communities in New Zealand in 2019 and 2020.FindingsThe paper highlights that people are capable at defining and assessing their own resilience. The indicators enabled people identify and measure areas of low resilience and foster dialogue between locals and practitioners to strengthen it.Research limitations/implicationsPeople-centred indicators also have limitations and pose challenges. Their development requires strong facilitation skills; it limitedly enables comparison across communities and implies downward accountability.Practical implicationsThe findings should stimulate discussions about who should measure resilience and for whom such measurement is it for. It provides a tool kit that can be used by practitioners and policy makers to measure and strengthen community resilience.Originality/valueMost resilience indicators is outsider-driven and limitedly involves local people. This study uses a radically different approach placing people at the centre of resilience measurement.

Description: PurposePersons with disabilities face the impacts of disasters differently. Early warning systems can be one of the powerful tools to reduce the vulnerabilities of persons with disabilities and mitigate the impacts of disasters. The main objective of this study was to assess the disability inclusiveness of the current early warning system (EWS) in flood-prone areas of Bangladesh.Design/methodology/approachA qualitative method was focused on getting in-depth information. Persons with disabilities participated in focus group discussions (FGDs) and shared the inclusiveness and gaps of the current EWS. Through extensive literature review, a checklist was developed to conduct the FGDs. QDA Miner 6.0.6 software was used for coding and analyzing the data.FindingsResults indicated that, though persons with disabilities have proper risk knowledge, the current monitoring and warning service, dissemination and communication, and response capability are not fully inclusive. A significant gap in the EWS was found in response capability. Even if somehow persons with disabilities manage to receive a warning about a flood, they lack the capacity to respond to the warning.Research limitations/implicationsThe study proposed that to make an EWS inclusive and effective, the concerned authorities should focus on all four parts of the EWS.Originality/valueStudies related to disability and disaster management are not very common. Conducting a qualitative study provided the persons with disabilities the opportunity to share their perspectives. Future studies can focus on vulnerability and capacity assessment of persons with disabilities to identify areas requiring interventions to enhance resilience.

Description: PurposeThis study hypothesizes the limitations of standardization as an interoperability development tool within emergency management.Design/methodology/approachPragmatism and Morgan's seminal organizational metaphors inform the conceptualization of the Interoperability Orange metaphor using symbolic logic and visual imagery.FindingsThe essence of standardization is homogeneity. Within emergency management, it is commonplace to develop legislation to standardize policies, procedures, training, equipment and terminology to engender interoperability among first responder and associated organizations. Standardization is achievable with similar or a small number of organizations. However, it is unlikely, if not impossible, in the context of disasters and catastrophes, given the broad range of organizations, groups and individuals typically involved. This diversity of cultures, subcultures, norms, values and indigenous and technical languages intimates that standardization is counterintuitive, particularly in disasters and catastrophes. The posited Interoperability Orange metaphor demonstrates that standardization as a policy, though desired, is theoretically unobtainable in enlarging multiorganizational environments. Thus, new perspectives, policies and solutions for interoperability are needed.Originality/valueThe posited theory builds on the growing body of metaphor-based emergency management research. The Interoperability Orange provides an accessible and easy-to-use communicative tool that aids theoretical cognition – notably within multicultural English as a Second Language environments – as it enables a deeper more critical and explicit understanding of the limits of standardization expressed via metaphor, symbolic logic and imagery.

Description: PurposeDisaster management agencies are mandated to reduce risk for the populations that they serve. Yet, inequities in how they function may result in their activities creating disaster risk, particularly for already vulnerable and marginalized populations. In this article, how disaster management agencies create disaster risk for vulnerable and marginalized groups is examined, seeking to show the ways existing policies affect communities, and provide recommendations on policy and future research.Design/methodology/approachThe authors undertook a systematic review of the US disaster management agency, Federal Emergency Management Agency (FEMA), examining its programs through a lens of equity to understand how they shape disaster risk.FindingsDespite a growing commitment to equity within FEMA, procedural, distributive, and contextual inequities result in interventions that perpetuate and amplify disaster risk for vulnerable and marginalized populations. Some of these inequities could be remediated by shifting toward a more bottom-up approach to disaster management, such as community-based disaster risk reduction approaches.Practical implicationsDisaster management agencies and other organizations can use the results of this study to better understand how to devise interventions in ways that limit risk creation for vulnerable populations, including through community-based approaches.Originality/valueThis study is the first to examine disaster risk creation from an organizational perspective, and the first to focus explicitly on how disaster management agencies can shape risk creation. This helps understand the linkages between disaster risk creation, equity and organizations.

Description: PurposeThis paper builds on existing studies by drawing on Conservation of Resources theory to explore the losses, psychological impacts as well as recovery processes of the 2017/18 volcanic disaster on Ambae Island, Vanuatu.Design/methodology/approachThis discussion is based on local perspectives and personal accounts collected through a series of eight semi-structured interviews (five males and three females).FindingsThe volcanic activity and subsequent displacement and evacuation led to significant resource loss which had a spiralling nature, causing psychological harm. Locals invested resources to recover and protect against future loss in diverse ways and, as resource gains were secured, experienced emotional relief. Key to recovery and healing included returning “home” after being displaced and reinvigorating cultural practices to re-establish cultural continuity, community and identity. Resource gains spiralled as people reconnected and regained a sense of place, optimism and the motivation to rebuild.Originality/valueNumerous studies have drawn upon the Conservation of Resources (COR) theory to explore how resource loss can trigger psychological distress during environmental disasters; however, it has not been applied in Vanuatu, the most at-risk nation globally to natural hazards. This paper builds on existing studies by exploring personal accounts of resource loss, distress and recovery, and providing insights into resource spirals, caravans and passageways.

Description: Various space missions, including the Russian and Chinese interplanetary exploration collaboration in 2011 and the Phobos-Grunt space project to be relaunched by the Chinese in 2025, carry a soil preparation system (SOPSYS), which is an instrument used for scientific experiments. The design and manufacture of this precision instrument require stringent manufacturing processes and workflow of the highest quality, with every process in the project carefully monitored and controlled. All processes should be completed within the deadline so that the space project can be launched at the scheduled time. The colored Petri net (CPN) modeling method can describe a variety of resource types and execution logic, and it can be formally verified. Based on these advantages, we clearly describe the complex structure of the SPOSYS unit production process. In addition, we use critical time and the 6 sigma system to evaluate the availability and reliability of workflows, and we use elimination and simplification (ECRS) methods and constraint theory to improve the manufacturing process of the SOPSYS unit. We further provide optimization theories, methods, and insights for workflow management in time-sensitive and independent manufacturing systems.

Description: Automated seizure detection system based on electroencephalograms (EEG) is an interdisciplinary research problem between computer science and neuroscience. Epileptic seizure affects 1% of the worldwide population and can lead to severe long-term harm to safety and life quality. The automation of seizure detection can greatly improve the treatment of patients. In this work, we propose a neural network model to extract features from EEG signals with a method of arranging the dimension of feature extraction inspired by the traditional method of neurologists. A postprocessor is used to improve the output of the classifier. The result of our seizure detection system on the TUSZ dataset reaches a false alarm rate of 12 per 24 hours with a sensitivity of 59%, which approaches the performance of average human detector based on qEEG tools.

Description: The influence of size effect on the hydromechanical behavior of rock mass has long been recognized. As a result, analysis of the rock mass size effect has been developed. However, when conducting size effect studies, the representativeness of the sample is less considered. Therefore, combining the existing statistical methods and sampling methods, a comprehensive representative sampling method for rock mass is present. In this method, a large number of sample statistics of different sizes are provided in the progressive coverage method; then, the plane density of the track length is defined as the value of stratification to perform stratified sampling for representative samples. Furthermore, it is applied to a joint network model generated in accordance with the actual situation and compared with those of other methods. The sampling results show that the proposed method can provide a certain reference value for studying the scale-dependent behavior of rock mass mechanical parameters.

Description: The Linxing area is located in the north of the eastern margin of the Ordos Basin, which has great resource potential for tight gas. In this paper, fluid inclusion analysis and basin modeling are the main means to clarify the gas accumulation mechanism of the Upper Paleozoic in the Linxing area. Petrographic analysis shows that fluid inclusions can be classified into 5 types: aqueous inclusions, hydrocarbon-bearing aqueous inclusions, hydrocarbon inclusions, crystal-bearing aqueous inclusions, and aqueous-carbonic inclusions. According to the statistical analysis of homogenization temperature and salinity of fluid inclusions, combined with the burial-thermal evolution, the study area was divided into 3 areas: the inner-magma baking area, the middle-anomal thermal area, and the outer-normal thermal area. The gas accumulation characteristics are differences among the 3 areas, the closer to Zijinshan magmatic pluton, the earlier gas accumulation period; and the vertical gas accumulation in the inner-magma baking area and the middle-anomal thermal area was not a slow and gradual process from bottom to top. The period from the Middle Jurassic to the Early Cretaceous is the key period for rapid pressure accumulation in the Upper Paleozoic reservoirs, which is consistent with the period of natural gas accumulation. The area near the Zijinshan magmatic pluton was the high fluid potential area during the gas accumulation period, which indicates that natural gas and other fluids migrated from Zijinshan magmatic pluton to the surrounding area. It is concluded that in the Linxing area, the Zijinshan magmatic pluton had a significant impact on natural gas accumulation, and the natural gas accumulation model under the control of magmatic thermal-tectonic effect was proposed.

Description: With the increasingly close relations between cities in China, it is of great significance to explore the regular characteristics of the intercity connection. Through Tencent’s population migration heat and Baidu map big data, this paper analyzes the regular characteristics of the relations between complex cities based on such index as the rich node propensity index, preference level index, and relative heat index and also investigates the influence of geographical proximity factors on the external relations of different cities. The research has the following results. Firstly, the relations between cities have obvious club characteristics. The rich nodes tend to connect with the rich nodes, while the nonrich nodes tend to connect with the nonrich nodes. Secondly, the connection between cities has the effect of hierarchical proximity, and cities mainly establish spatial connections with cities of the same level and adjacent level. Thirdly, the relations between cities also have the effect of geographical proximity, and the degree of influence of geographical proximity in low-level cities is greater than that in high-level cities. Fourthly, the external connection mode of high-level cities is to establish close contact with high-level cities adjacent to the level, with strong attraction to low-level cities adjacent to the location at the same time. The low-level cities are closely related to the high-level cities adjacent to the location and other cities of geographical proximity or adjacent level. This study helps to further understand the complex characteristics and laws of intercity connections and urban networks.

Description: In Nepal, forest management priority is shifting to scientific management from conventional management. Though, the forest officials claims that scientific management is beneficial to the forest user groups, comparative financial assessment with conventional management remains unexplored. Following a case study approach, this study compares financial efficiency of two forest management systems in the community forests, focusing on benefit-cost ratio. The study conducted documents review, focus group discussions, and rapid survey to quantify costs and benefits from each forest management system. Conventional management gave a higher benefit-cost ratio to the forest user groups, irrespective of whether forest products are sold at a subsidized price or par with the market price. However, scientific management required high forest management costs and thus had a lower benefit-cost ratio. Sensitivity analysis between two systems revealed that conventional management gave a higher benefit-cost ratio in all cases. The study concludes that forest user groups would bear financial loss if they do not fix the price of the timber at par with the market in scientific management, and in such a case, the tagged price will be beyond affordability of the forest users. Furthermore, scientific management has discouraged kind contribution of users in managing forest. Besides, social and environmental consequences of scientific management cannot be ignored. Hence, the study argues for reconsidering current scientific management considering likely economic and social consequences to the forest user groups.

Description: The seepage of gas-liquid two-phase flow in fracture is a commonly found phenomenon in nature. To reveal the underlying mechanism and the critical condition of the chaos occurrence, a stochastic gas-liquid two-phase flow seepage model is established, and then investigated through a numerical simulation and a horizontal Hele-Shaw experiment. The numerical simulation and laboratory experiment results show that the seepage chaos of gas-liquid two-phase flow takes place when the relative saturation is in the range of gas relative saturation 44%-70%, and the occurrence probability can be expressed in polynomials. The chaos probability exceeds 80% when the relative saturation of gas is 47%-65%, and the chaos probability is 100% when the relative gas saturation is 57%-60%. It is found that the stochastic variation of gas connection cluster and the compressibility of gas lead to a remarkable change of pressure gradient of the gas-liquid flow both in magnitude and direction. Therefore, the turbulent flow is formed, the kinetic energy of fluid transport decreases gradually, and the flow is stopped at last.

Description: An effective porosity is defined as the ratio of volume of interconnected pore space to total volume of a porous sample. It controls the magnitude of fluid flow and is a key parameter in the assessment of recoverable resources. However, its accurate measurement in tight formations is challenging, due to their complex pore structure and lithofacies heterogeneity. In this study, porosities of sixteen lacustrine shale samples from the second Member of the Kongdian Formation (Ek2) in the Cangdong Sag, Bohai Bay Basin were measured and compared using multiple methods and sample sizes to compare and contrast the effective porosity results. The methods included helium pycnometry (HP; cubes of 1 cm3 and grains at 500-841 μm), water immersion porosimetry (WIP; cubes), mercury intrusion porosimetry (MIP; cubes), and nuclear magnetic resonance (NMR; cubes). Finally, samples were completely sealed using paraffin for bulk density measurements to evaluate the extent of potential clay swelling in shale samples involving probing fluids. Results from the HP, WIP, and MIP methods for skeletal density, bulk density, and effective porosity with cubic samples were compared. While very similar skeletal densities were found for all three methods, a lower bulk density, and therefore lower porosity, from the MIP approach can be attributed to the experimental conditions (e.g., vacuum efficiency, applied pressure, wettability of water/helium vs. mercury) and the probable presence of pores with diameters larger than 50 μm not measurable by MIP. Furthermore, the HP porosity of granular samples with 500-841 μm grain sizes can be regarded as approaching the total porosity. The complicated relationship between WIP and NMR porosities may result from the heat-induced volatilization of moisture in pores during NMR tests, and countercurrent imbibition of water replacing the residual hydrocarbons during the saturation process for sample preparation in both tests. The swelling behavior of the lacustrine Ek2 shale with water is not significant because of the low content of expansive clay minerals. In summary, the WIP and HP methods are recommended for effective porosity measurement, whereas the NMR and MIP methods are invaluable for the measurement of pore-size distribution, with additional information on the effective porosity.

Description: A tuned mass damper inerter (TMDI) is a new class of passive control device based on the inclusion of an inerter mechanism into a conventional tuned mass damper (TMD). The inerter device provides inertial resisting forces to the controlled system, through relatively small masses, converting it in a mechanism with the potential to enhance the performance of passive energy dissipating systems. This work presents a study of an optimal TMDI design through an exhaustive search process. TMDI device design using the cited parameter selection methodology consists in the determination of the damper critical damping ratio, ζTMDI, and frequency ratio, υTMDI, which result in the minimum structural response of a multidegree of freedom structural system, considering predefined values for mass ratio (µ) and inertance ratio (β). The used optimization process examines all possible damping device design parameter combinations to select the set of values that results in the best device performance to reduce response parameters in a structure. Four different optimization processes are performed by independently minimizing four performance indices: J1 associated to the reduction of the structure’s maximum peak displacement, J2 calculates the minimal RMS value for the structure’s peak displacement, J3 seeks by the minimal peak interstorey drift, and JP determines the lowest value for a linear weighted combination of the abovementioned three indices. A numerical example is developed with the purpose of validating the proposed optimization procedure and to evaluate the benefits of using TMDI as controlling devices for structures under seismic excitation, by carrying out a comparative analysis to contrast the performance of the optimization alternatives developed, running up to 1968192 cases. The obtained results show that devices designed based on exhaustive search optimization produce peak displacement reductions of up to 35% and peak structure displacement RMS reductions of up to 30%.

Description: The lower Silurian Longmaxi Formation hosts a highly productive shale gas play in the Zhaotong region of southern China. According to core observation, X-ray diffraction analyses, and scanning electron microscopy (SEM) observations, the shale comprises primarily quartz, carbonate minerals, and clay minerals, with minor amounts of plagioclase, K-feldspar, and pyrite. The clay mineral content ranges from 15.0% to 46.1%, with an average of 29.3% in the Zhaotong region. Organic geochemical analyses show that the Longmaxi Formation has good potential for shale gas resources by calculating total organic carbon, vitrinite reflectance, and gas content. Scanning electron microscope images demonstrate that reservoir pore types in the Longmaxi shale include organic pores, interparticle pores, intercrystalline pores, intraparticle pores, and fractures. Reservoir distribution is controlled by lithofacies, mineral composition, and geochemical factors. In addition, we investigated the relationships between reservoir parameters and production from 15 individual wells in the Zhaotong region by correlation coefficients. As a result, the brittleness index, total organic carbon (TOC), porosity, and gas content were used to define high-quality reservoirs in the Longmaxi shale. Based on these criteria, we mapped the thickness and distribution of high-quality reservoirs in the Longmaxi Formation and selected highlighted several key sites for future exploration and development.

Description: In the present study, we employ fluorescence spectroscopy, dynamic light scattering, and molecular docking methods. Binding of anticancer drug anastrozole with human lysozyme (HL) is studied. Binding of anastrozole to HL is moderate but spontaneous. There is anastrozole persuaded hydrodynamic change in HL, leading to molecular compaction. Binding of anastrozole to HL also decreased in vitro lytic activity of HL. Molecular docking results suggest the electrostatic interactions and van der Waals forces played key role in binding interaction of anastrozole near the catalytic site. Binding interaction of anastrozole to proteins other than major transport proteins in blood can significantly affect pharmacokinetics of this molecule. Hence, rationalizing drug dosage is important. This study also points to unrelated effects that small molecules bring in the body that are considerable and need thorough investigation.

Description: Controlling and maintaining the orientation of the balloon-borne gondola for high-altitude flight is a prerequisite for ensuring the pointing control of observation instruments. When the balloon-borne gondola is flying in the stratosphere of the atmosphere, the existing external interferences will be converted into the coupling moment to the azimuth control system. Meanwhile, those uncertain factors and the frictional nonlinearity of the control system will also cause a certain magnitude of coupling moment. The existence of such coupling moment largely impacts on the accuracy and stability of the orientation control for the angular momentum exchange devices of the balloon-borne gondola. To address such an issue, this paper proposes and implements a novel type of integrated decoupler device. With this decoupler adopted, the aziDmuth control system could sense the existence of coupling torque and azimuth fluctuations quickly and suppress the influences of external interference, uncertain factors, and system structure nonlinearity on the azimuth control effectively, thereby improving the control accuracy of the azimuth control system. Both simulations and experiments are conducted to verify the effectiveness of the proposed device. The results show that the integration of the decoupler and the controller of the azimuth control system provide the azimuth control of the balloon-borne gondola with high accuracy and stability. Such a decoupler device design has a broad potential and could not only be used for balloon-borne gondola control but also could be applied onto other control systems using angular momentum exchange devices as actuators.

Description: When mine water inrush accidents occur, timely and accurately identifying the water inrush source plays an important role in determining the cause of water inrush and making a solution to a disaster. According to the differences of water chemical composition in each water sources of mine, eight kinds of indicators of water chemical composition were selected as sample variables for water inrush source identification. On this basis, an identification model of water inrush source was established by using principal component analysis (PCA) and Fisher discriminant analysis (FDA) combined. The model was used to identify the water inrush source of 14 groups of training samples and 12 groups of samples to be judged in different water sources of the Xiandewang coal mine, and it was compared with the results of the conventional identification model which used the FDA method. Results of this study showed that having processed data by using the PCA method can effectively eliminate the effects of information superposition between sample indicators, and the identification accuracy of mine water inrush source was significantly increased. Related study in this paper can provide some basis and reference for the study of mine water inrush source identification technology.

Description: The abundance of organic matter in shales, which has a direct effect on the hydrocarbon generation potential of shales, is an important organic geochemical parameter for evaluating shale gas reservoirs. The total organic carbon content (TOC content) in shale is controlled by the abundance of original sedimentary organic matter. Therefore, it is very important to study the mechanism of organic matter enrichment in shale. In this paper, the Lower Cambrian marine shales from the Lower Yangtze region are selected as the research subject, most of which originate from a typical area well called Well JXY1. The degree of pyritization (DOP) is used to characterize the redox environment of the water body, while the P/Al ratio is used to analyze the biological productivity of paleoseawater. The paleosalinity of seawater is calculated via carbon and oxygen isotope analysis. In addition, the early Cambrian hydrothermal activities were studied by using core description; Si, Al, Fe, and Mn elemental analysis; and oxygen isotope calculations. The results show that during the early Cambrian Wangyinpu sedimentary period, the seawater was an anaerobic water body with H2S, and the oxygen concentration was approximately 0 mL/L. In the middle stages of the Wangyinpu sedimentary period, the water body had the strongest reducibility and the highest biological productivity. Moreover, the paleoocean in this period between the Yangtze plate and the Cathaysian plate was greatly affected by hydrothermal activities, with temperatures ranging from 90°C to 120°C. Active hydrothermal activities promoted high biological productivity and an anaerobic environment, both of which were conducive to the preservation and enrichment of organic matter, resulting in extremely high TOC content in the Wangyinpu shales (from 6.5% to approximately 16%).

Description: Gates are important operating facilities and resources in civil airports. It is a core task in the airport operation management to select reasonable gates for inbound and outbound flights. We present a continuous time formulation with second-order cone programming (SOCP) for the gate assignment problem which allocates flights to available gates to optimize both the transfer time of passengers and the robustness of the airport operations schedules. The problem is formulated as a mixed integer nonlinear program, and then, the quadratic objective that minimizes the walking distance of transferring passengers is linearized, and the objective that minimizes the variance of idle time at the gates is transformed to a second-order cone constraint with a linear objective function. Then, a Lagrangian relaxation algorithm is developed by exploiting the problem structure. Computational tests are carried out to illustrate the efficiency of the model and the algorithms. It is shown that the continuous time formulation is more efficient than the existing model, and the Lagrangian relaxation algorithm can obtain better solutions faster than a commercial solver.

Description: In this paper, we propose an innovative method for conventional triaxial tests of concrete with a confining cell. The polyvinyl chloride (PVC) pipe is used as a mould to cast concrete and also as a membrane to isolate the concrete specimen from oil under confinements. This method is termed as PMM (i.e., PVC pipe is used as a mould and membrane). However, a heat-shrink sleeve is used as a membrane in the traditional test method (TMM). Specimens were made from mortar without coarse aggregates in the present experiment. Under six confinements (0–70 MPa), the conventional triaxial compression tests were performed on ultrahigh-strength (150 MPa) and high-strength (82 MPa) mortar specimens by PMM and TMM. The results indicate the following: (i) there is a characteristic confinement p0; when the confinement is lower than p0, the strength by PMM is higher than that by TMM; on the contrary, when the confinement is higher than p0, the strengths by both methods are almost identical. In this work, p0 is between 0 and 5 MPa. (ii) When the confinement is 5–70 MPa, the relationship between the peak stress of high-strength mortar and confinement is characterized by a monotonically rising straight line; however, a monotonically rising upward convex curve describes the peak stress of ultrahigh-strength mortar related to the confinement. (iii) The residual strength using PMM is significantly higher than that using TMM at zero confinement or lower confinements, but the residual strengths by these two methods are approximately identical at higher confinements. (iv) The transverse cracks appear in the mortar specimen inside the PVC pipe after enduring a triaxial loading using PMM. However, there is no such phenomenon when TMM is applied.

Description: Electroencephalography-(EEG-) based control is a noninvasive technique which employs brain signals to control electrical devices/circuits. Currently, the brain-computer interface (BCI) systems provide two types of signals, raw signals and logic state signals. The latter signals are used to turn on/off the devices. In this paper, the capabilities of BCI systems are explored, and a survey is conducted how to extend and enhance the reliability and accuracy of the BCI systems. A structured overview was provided which consists of the data acquisition, feature extraction, and classification algorithm methods used by different researchers in the past few years. Some classification algorithms for EEG-based BCI systems are adaptive classifiers, tensor classifiers, transfer learning approach, and deep learning, as well as some miscellaneous techniques. Based on our assessment, we generally concluded that, through adaptive classifiers, accurate results are acquired as compared to the static classification techniques. Deep learning techniques were developed to achieve the desired objectives and their real-time implementation as compared to other algorithms.

Description: This paper studies the global stability of a discrete-time pathogen dynamic model with both cell-mediated and antibody immune responses. Both latently and actively infected cells are incorporated into the model. We discretize the continuous-time model by using the nonstandard finite difference (NSFD) method. We establish that NSFD preserves the nonnegativity and boundedness of the solutions of the model. We derive four threshold parameters which govern the existence and stability of the steady states. We establish by using the Lyapunov method, the global stability of the five steady states of the model. We illustrate our theoretical results by using numerical simulations.

Description: The high-temperature gas-cooled reactor pebble-bed module (HTR-PM) nuclear power plant consists of two nuclear steam supply system modules, each of which drives the steam turbine by the superheated steam flow and is fed by the heated-up water flow. The shared steam/water system induces mutual effects on normal operation conditions and transients of the nuclear power plant, which is worthy of safety concerns and intensive study. In this paper, a coupling code package was developed with the TINTE and vPower codes to understand how the HTR-PM operated. The TINTE code was used to analyze the reactor core and primary circuit, while the vPower code simulated the steam/water flow in the conventional island. Two TINTE models were built and coupled to one vPower model through the data exchange in the steam generator models. Using this code package, two typical transients were simulated by decreasing the primary flow rate or introducing the negative reactivity of one module. Important parameters, including the reactor power, the fuel temperature, and the reactor inlet and outlet helium temperatures of two modules, had been studied. The calculation results preliminarily proved that this code package can be further used to evaluate working performance of the HTR-PM.

Description: Using standard techniques from geometric quantization, we rederive the integral product of functions on ℝ2 (non-Euclidian) which was introduced by Pierre Bieliavsky as a contribution to the area of strict quantization. More specifically, by pairing the nontransverse real polarization on the pair groupoid ℝ2×ℝ¯2, we obtain the well-defined integral transform. Together with a convolution of functions, which is a natural deformation of the usual convolution of functions on the pair groupoid, this readily defines the Bieliavsky product on a subset of L2ℝ2.

Description: Chloride corrosion test was carried out in 4% NaCl solution to study the chloride corrosion resistance of rubber concrete. Rubber concrete was prepared by using 20 mesh, 1∼3 mm, and 3∼6 mm rubber particles instead of sand by 5%, 10%, 15%, and 20% of the cementitious material mass. The P-wave velocity and compressive strength of rubber concrete were measured. The microstructure of rubber concrete corroded by chloride was analyzed by SEM. The micromorphology was compared with the macrofailure characteristics under uniaxial compression. The results show that the rubber concrete was still in the early stage of erosion. With the increase of immersion time at the age of 110 days, the P-wave velocity and compressive strength of concrete were generally on the rise. Furthermore, during the period of erosion, the mechanical properties of rubber concrete increased with the increase of rubber particle size and decreased with the increase of the content. Therefore, when the rubber particle size was 3∼6 mm and the content was 5%, the antierosion performance was the best. This study has a certain guiding significance for the chloride corrosion resistance of rubber concrete.

Description: Background. Young people are challenged with sexual and reproductive health (SRH) problems due to limited access to services and information. It contributes a high burden of sexually transmitted disease, unsafe abortion, and premature mortality, especially in low-income countries like Ethiopia. Hence, this study aimed at assessing the SRH service utilization and associated factors among college students at West Arsi Zone in Oromia region, Ethiopia. Methods. Institutional-based cross-sectional study was conducted among 519 randomly selected college students from January 01, 2019, up to April 30, 2019. Data were collected through self-administered pretested questionnaires. Data entry and analysis for descriptive and logistic regression models were performed by using SPSS (version 23). The result was declared as statistically significant at p