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  • Articles  (19)
  • Other Sources
  • Articles: DFG German National Licenses  (19)
  • Key words. GPS  (11)
  • simulation  (8)
  • Springer  (19)
  • 1995-1999  (19)
  • Architecture, Civil Engineering, Surveying  (19)
  • 1
    Electronic Resource
    Electronic Resource
    A new formulation for the stochastic control of systems with bounded state variables: An application to a single reservoir system (1996)
    Springer
    Stochastic environmental research and risk assessment 10 (1996), S. 167-186 
    Details
    ISSN: 1436-3259
    Keywords: Reservoir stochastic theory ; reliability ; mean ; variance ; indicator function ; storage bounds ; nonlinear programming ; simulation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Architecture, Civil Engineering, Surveying , Energy, Environment Protection, Nuclear Power Engineering , Geography , Geosciences
    Notes: Abstract A new formulation is presented for the analysis of reservoir systems synthesizing concepts from the traditional stochastic theory of reservoir storage, moments analysis and reliability programming. The analysis is based on the development of the first and second moments for the stochastic storage state variable. These expressions include terms for the failure probabilities (probabilities of spill or deficit) and consider the storage bounds explicitly. Using this analysis, expected values of the storage state, variances of storage, optimal release policies and failure probabilities — useful information in the context of reservoir operations and design, can be obtained from a nonlinear programming solution. The solutions developed from studies of single reservoir operations on both an annual and monthly basis, compare favorably with those obtained from simulation. The presentation herein is directed to both traditional reservoir storage theorists who are interested in the design of a reservoir and modern reservoir analysts who are interested in the long term operation of reservoirs.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01581462
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  • 2
    Electronic Resource
    Electronic Resource
    Kernel bandwidth selection for a first order nonparametric streamflow simulation model (1998)
    Springer
    Stochastic environmental research and risk assessment 12 (1998), S. 33-52 
    Details
    ISSN: 1436-3259
    Keywords: Keywords: Streamflow ; simulation ; nonparametric
    Source: Springer Online Journal Archives 1860-2000
    Topics: Architecture, Civil Engineering, Surveying , Energy, Environment Protection, Nuclear Power Engineering , Geography , Geosciences
    Notes: Abstract A new approach for streamflow simulation using nonparametric methods was described in a recent publication (Sharma et al. 1997). Use of nonparametric methods has the advantage that they avoid the issue of selecting a probability distribution and can represent nonlinear features, such as asymmetry and bimodality that hitherto were difficult to represent, in the probability structure of hydrologic variables such as streamflow and precipitation. The nonparametric method used was kernel density estimation, which requires the selection of bandwidth (smoothing) parameters. This study documents some of the tests that were conduced to evaluate the performance of bandwidth estimation methods for kernel density estimation. Issues related to selection of optimal smoothing parameters for kernel density estimation with small samples (200 or fewer data points) are examined. Both reference to a Gaussian density and data based specifications are applied to estimate bandwidths for samples from bivariate normal mixture densities. The three data based methods studied are Maximum Likelihood Cross Validation (MLCV), Least Square Cross Validation (LSCV) and Biased Cross Validation (BCV2). Modifications for estimating optimal local bandwidths using MLCV and LSCV are also examined. We found that the use of local bandwidths does not necessarily improve the density estimate with small samples. Of the global bandwidth estimators compared, we found that MLCV and LSCV are better because they show lower variability and higher accuracy while Biased Cross Validation suffers from multiple optimal bandwidths for samples from strongly bimodal densities. These results, of particular interest in stochastic hydrology where small samples are common, may have importance in other applications of nonparametric density estimation methods with similar sample sizes and distribution shapes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004770050008
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  • 3
    Electronic Resource
    Electronic Resource
    Simulation assessment of incident detection by cellular phone call-in programs (1999)
    Springer
    Transportation 26 (1999), S. 399-416 
    Details
    ISSN: 1572-9435
    Keywords: cellular telephones ; incident detection ; simulation ; traffic modeling ; wireless communications
    Source: Springer Online Journal Archives 1860-2000
    Topics: Architecture, Civil Engineering, Surveying
    Notes: Abstract This research study was designed to assess by simulation the efficacy of incident detection by cellular phone call-in programs. The assessment was conducted by varying the proportion of drivers with cellular phones on the highway so as to mirror the cellular industry statistics that show a continued growth of ownership of cellular phones in the United States. An analytical model, which combined simulation and the limited field data available in the literature, was used to determine measures of effectiveness of the cellular phone-based detection system. The results showed that a cellular phone detection system offers fast incident detection times and higher detection rates for both shoulder and lane blocking incidents. For example, in moderate traffic flow (i.e. 1,550 vehicles per hour per lane), 90 percent of incidents blocking two lanes were detected in 1.5 minutes when the proportion of drivers with cellular phones was one out of 10 drivers, even with only 20 percent of them willing to report incidents. When the current proportion of cellular ownership, i.e. 1 out of 3, was used in the simulation, the detection time improved to 0.8 minutes. The simulation analysis of incident detection by cellular phones also showed that there is a direct relationship between the probability of detection and the detection time; that is, the specification of a higher detection rate resulted in slower detection times. This is in sharp contrast with the results of field study of automatic incident detection (AID) systems which demonstrated an inverse relationship between probability of detection and detection time.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1005283307060
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  • 4
    Electronic Resource
    Electronic Resource
    The Ionosphere-weighted GPS baseline precision in canonical form (1998)
    Springer
    Journal of geodesy 72 (1998), S. 107-111 
    Details
    ISSN: 1432-1394
    Keywords: Key words. GPS ; Baseline precision ; Gain-numbers ; Ionosphere
    Source: Springer Online Journal Archives 1860-2000
    Topics: Architecture, Civil Engineering, Surveying
    Notes: Abstract. In this contribution we consider the precision of the floated and the fixed GPS baseline for the case of weighted ionosphere. Canonical forms of the baseline variance matrices are developed for different measurement scenarios. These forms make the relation between the various variance matrices transparent and thus present a simple way of studying their relative merits. It is also shown how these canonical forms give an intrinsic description of the gain in baseline precision which is experienced when the carrier-phase double-differenced ambiguities are treated as integers instead of as reals. The dependence of this gain on the various contributing factors, such as the decorrelation of the ionosphere, is also included.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s001900050152
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  • 5
    Electronic Resource
    Electronic Resource
    Impact of temporal correlations on GPS-derived relative point positions (1999)
    Springer
    Journal of geodesy 73 (1999), S. 246-258 
    Details
    ISSN: 1432-1394
    Keywords: Key words. GPS ; Temporal correlations ; Sensitivity analysis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Architecture, Civil Engineering, Surveying
    Notes: Abstract. Due to the steady progress in global positioning system (GPS) technology and methods of data evaluation, it is possible to obtain highly precise relative point positions also for extensive geodetic networks. However, some limiting influences such as temporal correlations of observational data are neglected in most of the GPS processing programs. Therefore, it is necessary to consider the impact of these neglected correlations on the coordinates and their accuracy measures. In this paper the sensitivity and reliability of GPS positioning over long baselines when temporal correlations are modelled with the aid of a correlation function are discussed. The implementation in the variance–covariance matrix and the subsequent evaluation process require a considerable amount of computing time and memory. Therefore it is necessary to use appropriate numerical methods such as approximated matrix inversion in order to reduce the numerical requirements. After the description of the methodical and numerical handling of the temporal correlations, exemplary results are given to illustrate the effects on position and accuracy of GPS stations.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s001900050241
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  • 6
    Electronic Resource
    Electronic Resource
    Precision, volume and eigenspectra for GPS ambiguity estimation based on the time-averaged satellite geometry (1997)
    Springer
    Journal of geodesy 71 (1997), S. 290-301 
    Details
    ISSN: 1432-1394
    Keywords: Key words. GPS ; ambiguity ; volume
    Source: Springer Online Journal Archives 1860-2000
    Topics: Architecture, Civil Engineering, Surveying
    Notes: Abstract. In this contribution we consider the time-averaged GPS single-baseline model and study in a qualitative sense its relation with the geometry-free model and the geometry-based model. The least-squares estimators of the model are derived and their properties discussed. Special attention is given to the ambiguity search space, since it plays such a crucial role in the problem of integer ambiguity estimation and validation. Easy-to-evaluate, closed-form expressions are presented for the volumes of the ambiguity search spaces that belong to the geometry-free model, the single-epoch geometry-based model and the time-averaged model. By means of an eigenvalue analysis, the geometry of the ambiguity search spaces is revealed and its impact on the search for the integer least-squares ambiguities discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s001900050097
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  • 7
    Electronic Resource
    Electronic Resource
    On the sensitivity of the location, size and shape of the GPS ambiguity search space to certain changes in the stochastic model (1997)
    Springer
    Journal of geodesy 71 (1997), S. 541-551 
    Details
    ISSN: 1432-1394
    Keywords: Key words. GPS ; Ambiguity search space ; Stochastic model
    Source: Springer Online Journal Archives 1860-2000
    Topics: Architecture, Civil Engineering, Surveying
    Notes: Abstract. In this contribution we analyse in a qualitative sense for the geometry-free model the dependency of the location, the size and the shape of the ambiguity search space on different factors of the stochastic model. For this purpose a rather general stochastic model is used. It includes time-correlation, cross-correlation, satellite elevation dependency and the use of an a priori weighted ionospheric model, having the ionosphere-fixed model and the ionosphere-float model as special cases. It is shown that the location is invariant for changes in the cofactor matrix of the phase observables. This also holds true for the cofactor matrix of the code observables in the ionosphere-float case. As for time-correlation and satellite elevation dependency, it is shown that they only affect the size of the search space, but not its shape and orientation. It is also shown that the least-squares ambiguities, their variance matrix and its determinant, for, respectively, the ionosphere-fixed model, the ionosphere-float model and the ionosphere-weighted model, are all related through the same scalar weighted mean, the weight of which is governed by the variance ratio of the ionospheric delays and the code observables. A closed-form expression is given for the area of the search space in which all contributing factors are easily recognized. From it one can infer by how much the area gets blown up when the ionospheric spatial decorrelation increases. This multiplication factor is largest when one switches from the ionosphere-fixed model to the ionosphere-float model, in which case it is approximately equal to the ratio of the standard deviation of phase with that of code. The area gives an indication of the number of grid points inside the search space.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s001900050122
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  • 8
    Electronic Resource
    Electronic Resource
    On the internal stability of GPS solutions (1997)
    Springer
    Journal of geodesy 72 (1997), S. 1-10 
    Details
    ISSN: 1432-1394
    Keywords: Key words. GPS ; Kalman filtering ; Internal stability
    Source: Springer Online Journal Archives 1860-2000
    Topics: Architecture, Civil Engineering, Surveying
    Notes: Abstract. Internal stability is referred to as the uniform asymptotic stability of Kalman filtering solutions, addressing the effects of initial-state errors, observation sample rates, lengths of observation sessions and so on. This paper presents the theory of the internal stability of GPS solutions, including mathematical definitions, properties and theorems addressing the dependence of internal stability of the filtering solutions on the controllability and observability of a GPS dynamic positioning system. The theory has been applied in analysing the stability performance of different GPS positioning modes, and the actual GPS positioning results have demonstrated graphically the asymptotic convergence of those stable solutions versus observation tracking time/filtering time-steps. The internal stability is therefore considered as an important performance criterion to evaluate different GPS positioning solutions.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s001900050143
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  • 9
    Electronic Resource
    Electronic Resource
    Minimal detectable biases of GPS data (1998)
    Springer
    Journal of geodesy 72 (1998), S. 236-244 
    Details
    ISSN: 1432-1394
    Keywords: Key words. GPS ; MDB ; Outliers ; Cycle slips
    Source: Springer Online Journal Archives 1860-2000
    Topics: Architecture, Civil Engineering, Surveying
    Notes: Abstract. In this contribution closed-form expressions are given for the minimal detectable biases of single- and dual-frequency pseudo-range and carrier-phase data. They are given for three different single-baseline models. These are the geometry-free model and two variants of the geometry-based model, namely the roving and stationary variants. The baselines are considered to be sufficiently short such that orbital uncertainties in the fixed orbits and residual ionospheric and tropospheric delays can be assumed absent. The stochastic model used is one that permits cross-correlation and the use of different variances for individual GPS observables, including the possibility to weigh the observables in dependence on which satellite is tracked.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s001900050163
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  • 10
    Electronic Resource
    Electronic Resource
    Improving the orbit estimates of GPS satellites (1999)
    Springer
    Journal of geodesy 73 (1999), S. 147-157 
    Details
    ISSN: 1432-1394
    Keywords: Key words. GPS ; Solar radiation pressure ; Orbit estimation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Architecture, Civil Engineering, Surveying
    Notes: Abstract. The Extended Center for Orbit Determination in Europe (CODE) Orbit Model, an empirical orbit model proposed by Beutler and colleagues in 1994, has been tested extensively since January 1996. Apart from six osculating Keplerian elements, this orbit model consists of nine (instead of the conventional two) parameters to take into account the deterministic part of the force field acting on the satellites. Based on the test results an improved orbit parameterization is proposed. The new orbit parameterization consists of the conventional two parameters plus three additional parameters, a constant and two periodic terms (a cosine and a sine term), in the X-direction to model the effects of the solar radiation pressure. Results based on one full year of routine orbit estimation, using the original and the new orbit parameterization, are presented to demonstrate the superiority of the new approach. An improvement of the orbit estimates with at least a factor of two is observed!
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s001900050230
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  • 11
    Electronic Resource
    Electronic Resource
    GPS sensitivity analysis applied to non-permanent deformation control networks (1999)
    Springer
    Journal of geodesy 73 (1999), S. 158-167 
    Details
    ISSN: 1432-1394
    Keywords: Key words. GPS ; Sensitivity ; Accuracy ; Deformation experiment ; Non-permanent array
    Source: Springer Online Journal Archives 1860-2000
    Topics: Architecture, Civil Engineering, Surveying
    Notes: Abstract. This paper illustrates the surveys and the results obtained in an experiment whose goal is to evaluate the Global Positioning System (GPS) sensitivity and accuracy for deformation control on non-permanent network of different extensions. To this aim a high-precision device was properly built to set up known displacements along three orthogonal axes of a GPS antenna. One of the antennas in the considered GPS networks was moved according to centimeter and sub-centimeter displacements; after careful GPS data processing, it was evaluated whether these simulated deformations were correctly a posteriori detected and at which probability level. This experiment was carried out both on a local (baselines ranging between 3 and 30 km) and on a regional (baselines ranging between 300 and 600 km) GPS network. The results show that in the local network it is possible to identify the displacements at a level of 10 mm in height and at a level of 5 mm in horizontal position. The analysis of the regional network showed that it is fundamental to investigate new strategies to model the troposphere; in fact, it is necessary to improve the precision of the height in order to correctly identify displacements lower than 60–80 mm; on the contrary, horizontal displacements can be evidenced at the level of 20 mm.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s001900050231
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  • 12
    Electronic Resource
    Electronic Resource
    The geometry-free GPS ambiguity search space with a weighted ionosphere (1997)
    Springer
    Journal of geodesy 71 (1997), S. 370-383 
    Details
    ISSN: 1432-1394
    Keywords: Key words. GPS ; ambiguity ; ionosphere
    Source: Springer Online Journal Archives 1860-2000
    Topics: Architecture, Civil Engineering, Surveying
    Notes: Abstract. In this contribution the impact of a presumed presence or absence of the ionospheric delays on the quality of the least-squares ambiguities is analysed. The spatial correlation and the time correlation of the ionospheric delays are captured in an a priori ionospheric variance matrix. It is shown how the size and shape of the ambiguity search space is affected by the use of these a priori ionospheric weights. As a result an exact description can be given of the interpolatory character of the ambiguity variance matrix as function of the ionospheric weights. In order to give a qualitative analysis of the various effects, analytical rather than numerical results are emphasized.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s001900050105
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  • 13
    Electronic Resource
    Electronic Resource
    On the GPS widelane and its decorrelating property (1997)
    Springer
    Journal of geodesy 71 (1997), S. 577-587 
    Details
    ISSN: 1432-1394
    Keywords: Key words. GPS ; Ambiguity decorrelation ; Widelane ; Ionosphere
    Source: Springer Online Journal Archives 1860-2000
    Topics: Architecture, Civil Engineering, Surveying
    Notes: Abstract. In this contribution we consider the popular widelaning technique from the viewpoint of ambiguity decorrelation. It enables us to cast the technique into the framework of the least-squares ambiguity decorrelation adjustment (LAMBDA) and to analyse its relative merits. In doing so, we will provide answers to the following three questions. Does the widelane decorrelate? Does it explicitly appear in the automated transformation step of the LAMBDA method? Can one do better than the widelane? It is shown that all three questions can be answered in the affirmative. This holds true for the ionosphere-fixed case, the ionosphere-float case, as well as for the ionosphere-weighted case.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s001900050126
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  • 14
    Electronic Resource
    Electronic Resource
    A discrimination test procedure for ambiguity resolution on-the-fly (1998)
    Springer
    Journal of geodesy 72 (1998), S. 644-653 
    Details
    ISSN: 1432-1394
    Keywords: Key words. GPS ; Ambiguity resolution ; Acceptance test ; Discrimination test
    Source: Springer Online Journal Archives 1860-2000
    Topics: Architecture, Civil Engineering, Surveying
    Notes: Abstract. Ambiguity validation tests include the acceptance test and discrimination test, which are both important steps in the Global Positioning System ambiguity resolution process. An ambiguity discrimination test procedure based on a test statistic which is constructed by the difference (not the ratio as used in current procedures) between the minimum and second minimum quadratic form of the residuals in ambiguity identification, and its standard deviation, is proposed. The distribution function of the proposed test statistic is theoretically identified as a standard normal distribution when the known a priori variance factor is used, or as a Student's t distribution when the estimated variance factor is used. With this procedure, the ambiguity discrimination test is based on a more rigorous test statistic whose critical value can be calculated with any chosen level of significance. Test results indicate that the proposed ambiguity discrimination test procedure is reliable for use in ambiguity resolution on-the-fly.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s001900050204
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  • 15
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    Technical Communication: Two-Phase Stochastic Dynamic Programming Model for Optimal Operation of Irrigation Reservoir (1997)
    Springer
    Water resources management 11 (1997), S. 395-406 
    Details
    ISSN: 1573-1650
    Keywords: irrigation reservoirs ; operation ; water deficit ; yield response ; multicrop environment ; stochastic dynamicprogramming ; soil moisture ; water allocation ; simulation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Architecture, Civil Engineering, Surveying , Geography
    Notes: Abstract A two-phase stochastic dynamic programming model is developed for optimal operation of irrigation reservoirs under a multicrop environment. Under a multicrop environment, the crops compete for the available water whenever the water available is less than the irrigation demands. The performance of the reservoir depends on how the deficit is allocated among the competing crops. The proposed model integrates reservoir release decisions with water allocation decisions. The water requirements of crops vary from period to period and are determined from the soil moisture balance equation taking into consideration the contribution of soil moisture and rainfall for the water requirements of the crops. The model is demonstrated over an existing reservoir and the performance of the reservoir under the operating policy derived using the model is evaluated through simulation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1007914019102
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  • 16
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    Water Drainage in Layered Soils. Laboratory Experiments and Numerical Simulation (1997)
    Springer
    Water resources management 11 (1997), S. 437-444 
    Details
    ISSN: 1573-1650
    Keywords: water first and second drainage ; layered unsaturated soil ; experiment ; γ-radiation ; simulation ; finite differences ; periodically changing head
    Source: Springer Online Journal Archives 1860-2000
    Topics: Architecture, Civil Engineering, Surveying , Geography
    Notes: Abstract Experimental results during first and second drainage in a vertical column of saturated layered soil were compared to those predicted from simulation. The sample was composed of a sandyloam soil overlying a fine sand. The soil water content was measured by using γ-ray absorption method (241Am) and the water pressure through tensiometers, arranged vertically along the column and connected to pressure transducers. From the evaluation of moisture and pressure versus time, the characteristic curves Ψ(θ) of the layers were obtained and approximated by van Genuchten's analytical equation. The relationship K(θ) between hydraulic conductivity and moisture was estimated by van Genuchten's prediction model. Ψ(θ) and K(θ) equations were used as inputs in the numerical model. The drainage of water was simulated by Richard's partial differential equation, which was solved with the finite differences computational scheme type Laasonen. The upper and lower boundary conditions were zero flux and a periodically changing head respectively. Numerical results show a good agreement with experimental data, with small deviations for certain hours.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1007900415561
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  • 17
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    Performance Risk Analysis for Fukuoka Water Supply System (1998)
    Springer
    Water resources management 12 (1998), S. 13-30 
    Details
    ISSN: 1573-1650
    Keywords: risk ; reliability ; resiliency ; vulnerability ; drought risk index ; drought damage index ; simulation ; water supply ; reservoir operation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Architecture, Civil Engineering, Surveying , Geography
    Notes: Abstract In this study, simulation is used to evaluate the performance of the municipal water system in Fukuoka city. In combination with daily simulation model, a kind of risk model incorporating water demand prediction is presented. This model applies five risk indices: reliability, resiliency, vulnerability, drought risk index (DRI) and drought damage index (DDI). They aid in the identification of operation policies for the municipal water system, and the planning and operational policies obtained are aimed at achieving minimum risk for a given scenario of operation. In this paper, the performance risk of the municipal water system is investigated under three alternatives: (1) the existing system operation when available supply from the Chikugo river is decreased; (2) water restrictions for different percentages of reduction are implemented; and (3) available water supply increases when desalination of sea water is implemented. The results obtained show that savings of between 5 and 12% of water consumption from May 1, or increasing of daily desalination of sea water about 30 000 m3 or more, may efficiently decrease the performance risk of the Fukuoka water supply system. Potentials also exist for further increase of reservoir storage by more rational operation. The measure that more attention should be paid to increasing the water supply from stable sources is recommended as well.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1007951806144
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  • 18
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    A Comparative Study of Two Methods for Modeling Soil Water Regime in Agricultural Fields (1998)
    Springer
    Water resources management 12 (1998), S. 285-293 
    Details
    ISSN: 1573-1650
    Keywords: agrometeorological models ; PRZM ; simulation ; SWATRER ; water balance
    Source: Springer Online Journal Archives 1860-2000
    Topics: Architecture, Civil Engineering, Surveying , Geography
    Notes: Abstract Two methods widely used in agrometeorogical simulation models for describing field soil water regimes are compared and evaluated based on their ability to predict experimental data from a single field study. The first method is based on a numerical solution to the Richards' equation for describing water movement in the soil profile, while the second method is based on soil-water capacity terms. The evaluation of the performance of the two methods is based on goodness-of-fit statistics and graphical analysis. Results indicate that the first method is more accurate for both the upper and the lower soil zones; the second method, despite its low performance in the upper soil zone can adequately describe soil moisture conditions in the lower soil zones. Recommendations are made for model use based on comparison results, the intended model use, and the difficulty in the acquisition of required model inputs.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1008073824019
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  • 19
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    A Planning Model for the Fuerte-Carrizo Irrigation System, Mexico (1997)
    Springer
    Water resources management 11 (1997), S. 165-184 
    Details
    ISSN: 1573-1650
    Keywords: optimization ; linear programming ; simulation ; irrigation planning
    Source: Springer Online Journal Archives 1860-2000
    Topics: Architecture, Civil Engineering, Surveying , Geography
    Notes: Abstract A methodology is presented for planning the operation of the Fuerte-Carrizo irrigation system in northwest Mexico. The system has two storage dams, two irrigation districts, and water transfer capabilities between both dams. The methodology uses a combination of linear programming (LP) and simulation. The LP model maximizes the net return of the farmers, subject to restrictions of the system, availability of water and land, and water transfer relationships. The simulation model is programmed as a microcomputer interactive package simulating the performance of the system. The methodology has proven to be a useful tool to assist those responsible for the operation of the irrigation system.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1007910530591
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