ALBERT

Description: The use of biofuels helps to reduce the dependency on fossil fuels and therefore decreases CO2 emission. Ethanol mixed with gasoline in mandatory percentages has been used in many countries. However, production of ethanol mainly depends on food crops, commonly associated with problems such as governmental policies and social controversies. Sweet sorghum (Sorghum bicolor (L.) Moench) is one of the most potential and appropriate alternative crops for biofuel production because of its high biomass and sugar content, strong tolerance to environmental stress conditions and diseases, and wide adaptability to various soils and climates. The aim of this study was to select prospective varieties of sweet sorghum, optimum sowing times and densities to achieve high yields of ethanol production and to establish stable operational conditions in cultivating this crop. The summer-autumn cropping season combined with the sowing densities of 8.3–10.9 plant m−2 obtained the highest ethanol yield. Among cultivated locations, the soil with pH of 5.5 and contents of Al and Zn of 39.4 and 0.6 g kg−1, respectively, was the best condition to have an ethanol yield >5000 L ha−1. The pH ≥ 6.0 may be responsible for the significant reduction of zinc content in soils, which decreases both biomass of sweet sorghum and ethanol yield, while contents of N, P, K, organic carbon (OC) and cation exchange capacity (CEC), and Fe likely play no role. The cultivar 4A was the preferred candidate for ethanol production and resistant to pests and diseases, especially cut worm (Agrotis spp.).

Description: The main objective of this study is to assess the spatio-temporal dynamics of land cover/land use changes in the lower Mekong Delta over the last 40 years with the coastal Tran Van Thoi District of Ca Mau Province, Vietnam as a case study. Land cover/land use change dynamics are derived from moderate to high spatial resolution (Landsat and SPOT) satellite imagery in six time intervals ranging from 1973 to 2011. Multi-temporal satellite images were collected, georeferenced, classified using per-pixel method, validated, and compared in post classification for the land use/land cover change detection in decades. Seven major land cover/land use classes were obtained, including cultivated lands, aquaculture ponds, mangrove forest, melaleuca forest, built up areas, bare lands, and natural water bodies. The accuracies of the land cover/land use maps for 1973, 1979, 1989, 1995, 2004, and 2011 were 81%, 82%, 86%, 87%, 89%, and 89%, respectively. The results show that the area of cultivated lands reduced over the period 1973–2011, however, it still represents the dominant land use in the case study. Aquaculture ponds were almost absent in 1973 but greatly increased from 1995 to 2004, to represent 20% of the land surface in 2011. Overall, from 1973 to 2011, bare lands, cultivated lands, mangrove forest, and melaleuca forest decreased by 104 km2, 77 km2, 61 km2, and 5 km2, respectively. In contrast, aquaculture lands and built up areas increased by 123 km2 and 120 km2, respectively. Temporal analysis highlights that these changes took place mostly between 1995 and 2004. This study is a first step to identify the main drivers of land use changes in this delta region, which include economical policies as well as demographic, socio-economic, and environmental changes.

Description: Energies, Vol. 11, Pages 2018: Technological Solutions for Recycling Ash Slag from the Cao Ngan Coal Power Plant in Vietnam Energies doi: 10.3390/en11082018 Authors: Thriveni Thenepalli Nguyen Thi Minh Ngoc Lai Quang Tuan Trinh Hai Son Ho Huu Hieu Dang Tran Nhu Thuy Nguyen Thi Thanh Thao Duong Thi Thanh Tam Doan Thi Ngoc Huyen Tran Tan Van Ramakrishna Chilakala Ji Whan Ahn Annually, coal-fired power plants in Vietnam discharge hundreds of thousand tons of coal ash. Most of this ash goes into the environment without treatment or any plan for the efficient reuse of this precious resource. There are many reasons for this, such as poor quality of the ash, no suitable and feasible ash treatment technology, a lack of awareness about environmental pollution and resource saving, and inappropriate sanctions and policies. This study analyzed and summarized information and data pertaining to the current status of the production, discharge, and utilization of coal ash from the Cao Ngan Power Plant (CNPP) in Thai Nguyen Province, Vietnam. In addition, the potential for applying advanced emission reduction technologies in order to recycle coal ash for cement production, as well as geographical, socio-economic, and market factors were assessed. This paper reveals the results of a preliminary assessment of carbon-mineralization technologies which seek to achieve the following three goals: (1) effectively disposing of coal ash to protect the environment and local community, (2) contributing to the nationally determined effort to mitigate greenhouse gas emissions which cause climate change, and (3) making value-added products and bringing economic benefits to a sustainable society.

Description: Materials, Vol. 11, Pages 1755: A Facile Synthesis Procedure for Sulfonated Aniline Oligomers with Distinct Microstructures Materials doi: 10.3390/ma11091755 Authors: Ramesh Karunagaran Campbell Coghlan Diana Tran Tran Thanh Tung Alexandre Burgun Christian Doonan Dusan Losic Well-defined sulfonated aniline oligomer (SAO) microstructures with rod and flake morphologies were successfully synthesized using an aniline and oxidant with a molar ratio of 10:1 in ethanol and acidic conditions (pH 4.8). The synthesized oligomers showed excellent dispersibility and assembled as well-defined structures in contrast to the shapeless aggregated material produced in a water medium. The synergistic effects among the monomer concentration, oxidant concentration, pH, and reaction medium are shown to be controlling parameters to generate SAO microstructures with distinct morphologies, whether micro sheets or micro rods.

Description: Sensors, Vol. 18, Pages 3186: Highly Accurate Step Counting at Various Walking States Using Low-Cost Inertial Measurement Unit Support Indoor Positioning System Sensors doi: 10.3390/s18103186 Authors: Van Thanh Pham Duc Anh Nguyen Nhu Dinh Dang Hong Hai Pham Van An Tran Kumbesan Sandrasegaran Duc-Tan Tran Accurate step counting is essential for indoor positioning, health monitoring systems, and other indoor positioning services. There are several publications and commercial applications in step counting. Nevertheless, over-counting, under-counting, and false walking problems are still encountered in these methods. In this paper, we propose to develop a highly accurate step counting method to solve these limitations by proposing four features: Minimal peak distance, minimal peak prominence, dynamic thresholding, and vibration elimination, and these features are adaptive with the user’s states. Our proposed features are combined with periodicity and similarity features to solve false walking problem. The proposed method shows a significant improvement of 99.42% and 96.47% of the average of accuracy in free walking and false walking problems, respectively, on our datasets. Furthermore, our proposed method also achieves the average accuracy of 97.04% on public datasets and better accuracy in comparison with three commercial step counting applications: Pedometer and Weight Loss Coach installed on Lenovo P780, Health apps in iPhone 5s (iOS 10.3.3), and S-health in Samsung Galaxy S5 (Android 6.01).

Description: Sensors, Vol. 18, Pages 3028: Time Slot Utilization for Efficient Multi-Channel MAC Protocol in VANETs Sensors doi: 10.3390/s18093028 Authors: VanDung Nguyen Tran Anh Khoa Thant Zin Oo Nguyen H. Tran Choong Seon Hong Eui-Nam Huh In vehicular ad hoc networks (VANETs), many schemes for a multi-channel media access control (MAC) protocol have been proposed to adapt to dynamically changing vehicle traffic conditions and deliver both safety and non-safety packets. One such scheme is to employ both time-division multiple access (TDMA) and carrier-sense multiple access (CSMA) schemes (called a hybrid TDMA/CSMA scheme) in the control channel (CCH) interval. The scheme can adjust the length of the TDMA period depending on traffic conditions. In this paper, we propose a modified packet transmitted in the TDMA period to reduce transmission overhead under a hybrid TDMA/CSMA multi-channel MAC protocol. Simulation results show that a MAC protocol with a modified packet supports an efficient packet delivery ratio of control packets in the CCH. In addition, we analyze the hybrid TDMA/CSMA multi-channel MAC protocol with the modified packet under saturated throughput conditions on the service channels (SCHs). The analysis results show that the number of neighbors has little effect on the establishment of the number of time slots in TDMA periods and on SCHs under saturated throughput conditions.

Description: IJERPH, Vol. 15, Pages 1456: A Bibliometric Analysis of the Global Research Trend in Child Maltreatment International Journal of Environmental Research and Public Health doi: 10.3390/ijerph15071456 Authors: Bach Xuan Tran Thang Van Pham Giang Hai Ha Anh Toan Ngo Long Hoang Nguyen Thuc Thi Minh Vu Ha Ngoc Do Vu Nguyen Anh Tuan Le Nguyen Tung Thanh Tran Nu Thi Truong Vuong Quan Hoang Tung Manh Ho Nhue Van Dam Thu Trang Vuong Hung Quang Nguyen Huong Thi Le Hoa Thi Do Mackenzie Moir Yoko Shimpuku Meghnath Dhimal Shalini Subash Arya Tu Huu Nguyen Suraj Bhattarai Carl A. Latkin Cyrus S.H. Ho Roger C.M. Ho Child maltreatment remains a major health threat globally that requires the understanding of socioeconomic and cultural contexts to craft effective interventions. However, little is known about research agendas globally and the development of knowledge-producing networks in this field of study. This study aims to explore the bibliometric overview on child maltreatment publications to understand their growth from 1916 to 2018. Data from the Web of Science Core Collection were collected in May 2018. Only research articles and reviews written in the English language were included, with no restrictions by publication date. We analyzed publication years, number of papers, journals, authors, keywords and countries, and presented the countries collaboration and co-occurrence keywords analysis. From 1916 to 2018, 47,090 papers (53.0% in 2010–2018) were published in 9442 journals. Child Abuse & Neglect (2576 papers; 5.5%); Children and Youth Services Review (1130 papers; 2.4%) and Pediatrics (793 papers, 1.7%) published the most papers. The most common research areas were Psychology (16,049 papers, 34.1%), Family Studies (8225 papers, 17.5%), and Social Work (7367 papers, 15.6%). Among 192 countries with research publications, the most prolific countries were the United States (26,367 papers), England (4676 papers), Canada (3282 papers) and Australia (2664 papers). We identified 17 authors who had more than 60 scientific items. The most cited papers (with at least 600 citations) were published in 29 journals, headed by the Journal of the American Medical Association (JAMA) (7 papers) and the Lancet (5 papers). This overview of global research in child maltreatment indicated an increasing trend in this topic, with the world’s leading centers located in the Western countries led by the United States. We called for interdisciplinary research approaches to evaluating and intervening on child maltreatment, with a focus on low-middle income countries (LMICs) settings and specific contexts.

Description: Sensors, Vol. 18, Pages 1843: Performance Evaluation of Relay Selection Schemes in Beacon-Assisted Dual-Hop Cognitive Radio Wireless Sensor Networks under Impact of Hardware Noises Sensors doi: 10.3390/s18061843 Authors: Tran Hieu Tran Duy Le Dung Seong Choi To solve the problem of energy constraints and spectrum scarcity for cognitive radio wireless sensor networks (CR-WSNs), an underlay decode-and-forward relaying scheme is considered, where the energy constrained secondary source and relay nodes are capable of harvesting energy from a multi-antenna power beacon (PB) and using that harvested energy to forward the source information to the destination. Based on the time switching receiver architecture, three relaying protocols, namely, hybrid partial relay selection (H-PRS), conventional opportunistic relay selection (C-ORS), and best opportunistic relay selection (B-ORS) protocols are considered to enhance the end-to-end performance under the joint impact of maximal interference constraint and transceiver hardware impairments. For performance evaluation and comparison, we derive the exact and asymptotic closed-form expressions of outage probability (OP) and throughput (TP) to provide significant insights into the impact of our proposed protocols on the system performance over Rayleigh fading channel. Finally, simulation results validate the theoretical results.

Description: IJERPH, Vol. 15, Pages 1174: Cost-of-Illness and the Health-Related Quality of Life of Patients in the Dengue Fever Outbreak in Hanoi in 2017 International Journal of Environmental Research and Public Health doi: 10.3390/ijerph15061174 Authors: Bach Xuan Tran Giang Thu Vu Long Hoang Nguyen Anh Tuan Le Nguyen Tung Thanh Tran Binh Thanh Nguyen Thao Phuong Thi Thai Carl A. Latkin Cyrus S. H. Ho Roger C. M. Ho Dengue fever (DF) outbreaks occur intermittently in Vietnam, and the most recent epidemic happened in 2017. However, attempts to measure the burden of DF in relation to the quality of life and the cost of treatment for patients during an epidemic period are constrained. This study explored the health-related quality of life (HRQOL) and the cost of illness among patients with dengue fever in Vietnam. A cross-sectional study was conducted in Bach Mai Hospital from September to November 2017. The EuroQol-5 dimensions-5 levels (EQ-5D-5L) was used to measure HRQOL. Cost-of illness was measured by collecting data about the direct medical cost, the non-medical cost, and the indirect cost. Among 225 patients, most of the participants experienced problems regarding mobility (62.3%), self-care (71.8%), usual activities (64.6%), and anxiety/depression (64.1%). The mean EQ-5D index was 0.66 (SD = 0.24). The median cost of illness for inpatient and outpatient groups were US $110.10 (IQR = US $4.40–1200.00) and US $36.10 (IQR = US $1.80–816.30), respectively. Indirect costs accounted for a major proportion in both groups. Lower-skilled workers and those with a higher severity of the disease had significantly lower HRQOL. Meanwhile, people who were inpatients, had comorbidities, had higher incomes, and who experienced a longer disease duration, had a higher cost of treatment. In conclusion, high costs and severe health deterioration, especially in psychological dimensions, were found in patients with DF in Vietnam. Strengthening primary health care services and communication campaigns are necessary to relieve the burden of diseases and could possibly contribute to effective DF control and prevention strategies.

Description: IJERPH, Vol. 15, Pages 981: Consumer Preference and Attitude Regarding Online Food Products in Hanoi, Vietnam International Journal of Environmental Research and Public Health doi: 10.3390/ijerph15050981 Authors: Anh Kim Dang Bach Xuan Tran Cuong Tat Nguyen Huong Thi Le Hoa Thi Do Hinh Duc Nguyen Long Hoang Nguyen Tu Huu Nguyen Hue Thi Mai Tho Dinh Tran Chau Ngo Thuc Thi Minh Vu Carl Latkin Melvyn Zhang Roger Ho This study aimed to examine: (1) how the Internet has changed consumers food-buying behavior and identify its associated factors; (2) consumers’ concern about food safety information of online food products. A cross-sectional study was performed from October to December 2015 in Hanoi—a Vietnamese epicenter of food service. One thousand seven hundred and thirty six (1736) customers were randomly chosen from food establishments of 176 communes. Data were collected through face-to-face interviews using structured questionnaires. The majority of participants reported using the Internet to search for food products (81.3%). The most crucial factors influencing food purchases through the Internet were convenience (69.1%) and price (59.3%). Only one-third of participants selected products based on accurate evidence about food safety certification or food origin. The majority of participants were concerned about the expiration date (51.6%), while brand (9.8%) and food licensing information (11.3%) were often neglected. People who were:(1) female, (2) highly influenced by online relationships, and (3) having difficulty in doing usual activities were more likely to look for online food products. These findings produce practical advice to consumers when purchasing their desired food products on the Internet, to online food retailers and to the Government of Vietnam to implement appropriate legislation regarding trading online food products.