per
kntu
Engineering Journal of Geospatial Information Technology
2008-9635
2014-03
1
2
1
14
article
A GIS-bsed Solution for using Hec-HMS Modclark Hydrologic Model in Iran
Ali Kalantari Oskuei
oskhom@gmail.com
1
Bahram Sagafian
2
Ali Asghar Alesheikh
3
Institute for Soil and Water Conservation
Institute for Soil and Water Conservation
K.N.Toosi University of Technology
Preparing data based on SHG coordinate and DSS format are known as among the main problems in running modclark hydraulic model within Hec-HMS. The main goal of this research has been providing a solution for the mentioned problem. To this end, Garango watershed was selected as the study area and a GIS-based research was conducted for determining flood intensity and prioritizing flood yield potential using Unit Response Approach and Modclark model in Hec-HMS environment. Rainfall-runoff gages measurements, gridded basin file, gridded precipitation file, gridded SCS curve number file, time of concentration and storage coefficient were the main required data to execute the research model. To do this research, the boundaries of Garango watershed and its four subwatersheds along with stream network were delineated using 1:25000 topographic maps. The map of Digital Elevation Model (DEM) and slope map of watershed were generated and then the physiographic characteristics of the subwatersheds extracted in GIS environment. In the next step, gridded basin file was created using HEC-GeoHMS, based on Standard Hydrologic Grid (SHG). One hour duration rainfall intensities were extracted and then using interpolation method, a gridded precipitation file was generated based on SHG coordinate system and DSS format. Gridded SCS curve number was also created and saved as DSS file. The next step was dedicated to calibrate and validate ModClark hydrologic model at the watershed outlet. Based on the flood index per area (f), Almalochai subwtershed was identified as the most flood active area. As a feature work, it was recommended that in Modclark-base simulations studies, different dimensions of SHG to be examined and the suitable grid dimension (a) be introduced for managing the flood area watersheds.
http://jgit.kntu.ac.ir/article-1-60-en.pdf
IS
Modclark
SHG
Unit Response Approach
per
kntu
Engineering Journal of Geospatial Information Technology
2008-9635
2014-03
1
2
15
32
article
Optimal Spatial Distribution of Sources of Electromagnetic Wave Propagation for Acquiring Best Qualitative Coverage (Using Genetic Algorithms in GIS)
Ebrahim Omidi Garakani
ebrahim.omidi@gmail.com
1
Ali Mansourian
2
Mohammad Saadi Mesgari
3
Ehsan Omidi Garakani
4
K.N.Toosi University of Technology
K.N.Toosi University of Technology
K.N.Toosi University of Technology
Amirkabir University of Technology
Optimal multiple viewpoints problem (OMVP) is an optimization problem, which could not be solved by using analytical methods, since there is not any distinct mathematical relationship between the positions of viewpoints and combinatorial viewshed. Due to the variety of applications of OMVP in communications, surveying, military, urban planning, etc., it is necessary to find a solution. Current solutions include many shortcoming, and disadvantages such as: “not considering the quality of coverage (quality of the received signal)” and “not being applicable because of high number of calculations”. In this paper, a new genetic method has been used to solve OMVP which resolves the mentioned shortcomings, considerably. In this method, each viewpoint is considered as a gene and each N viewpoint compose a chromosome. The quality problem is solved by considering electromagnetic wave attenuation model as the fitness function. The number of calculations has also been considerably reduced by integrated utilization of DEM and TIN, Were TIN vertices are used as the first genes instead of DEM pixels. The results of the practical test showed the flexibility and applicability of the proposed method for OMVP.
http://jgit.kntu.ac.ir/article-1-61-en.pdf
Viewshed
Wave propagation model
Optimal multiple viewpoints problem (OMVP)
Wave attenuation
Genetic algorithm
Optimization
TIN
per
kntu
Engineering Journal of Geospatial Information Technology
2008-9635
2014-03
1
2
33
50
article
Spectral Combination in Vector Gravimetric Boundary Value Problems
Mehdi Eshagh
eshagh@Kth.se
1
Royal Institute of Technology (KTH), Stockholm
If there are more than a unique type of boundary value problem, so there may not be just one solution for problem. The vector gravimetric boundary value problem is one of the types of such problems which include two integral solutions. In this paper, this problem is solved in spectral domain, and then the solutions will be converted to integrals in spatial domain. The kernels of these integrals are divergent but by using spectral combination they become convergent and even they will have the downward continuation property. To do so, different stochastic estimators for recovering the disturbing potential at sea level are presented, and for each one of them the spectral coefficients are derived. Numerical computations show that the convergent kernels have the property of modifying the integral formulas in addition to the downward continuation and Wiener filtering, so that the kernels are well-behaved and reduce the contributions of far-zone data easily. The method presented in this paper can be applied for combination of satellite or air-borne vector gravimetric data.
http://jgit.kntu.ac.ir/article-1-62-en.pdf
Spherical harmonics
Vector field
Orthogonality property
Convergence
Biased and unbiased estimators
per
kntu
Engineering Journal of Geospatial Information Technology
2008-9635
2014-03
1
2
51
68
article
Prioritizing Underground Storage Tanks of Natural Gas Using GIS and TOPSIS
Mehdi Zangeneh
m.zangeneh@ut.ac.ir
1
Mahmood Reza Delavar
2
Behzad Moshiri
3
saeed Ghavampour
4
Meysam Effati
5
University of Tehran
University of Tehran
University of Tehran
Ghazvin University of Work
University of Tehran
In this study, an efficient approach is suggested to prioritize the natural gas storage in existing underground reservoirs. The paper uses expert knowledge and integrates the Geospatial Information System (GIS) with spatial multi criteria decision making .The proposed method is based on TOPSIS as well as Hierarchical Additive Weighting Method. In order to consider different options, the most important possible criteria have been considered in this study, including: reservoir characteristics, distance from the center of gravity taking, distance from production centers, distance from the country's road network, the temperature around the reservoir areas, environmental characteristics of the reservoir, consumption gas in areas around the reservoir, population density, and the number of important industrial centers covered by each of the reservoirs. To evaluate the results of research, results of implemented methods were compared with each others and according to evaluation obtained from several experts the final prioritization of different reservoirs due to their performances has been done. The results indicate that TOPSIS is more precise than Hierarchical Additive Weighting Method, and conform to experts opinions about prioritization of natural gas storage in underground reservoirs.
http://jgit.kntu.ac.ir/article-1-63-en.pdf
Geospatial Information Systems
Spatial Multi Criteria Decision Making
Underground Storage of Natural Gas
Hierarchical Additive Weighting Method
TOPSIS
per
kntu
Engineering Journal of Geospatial Information Technology
2008-9635
2014-03
1
2
69
80
article
Landslide Susceptibility Zoning, Using Weight of Evidence Probabilistic Model
Hamid Reza Pourghasemi
1
Hamid Reza Moradi
Morady5hr@yahoo.com
2
Majid Mohammadi
3
College of Natural Resources and Marine Science, Tarbiat Modares University, Mazandaran
College of Natural Resources and Marine Science, Tarbiat Modares University, Mazandaran
College of Natural Resources and Marine Science, Tarbiat Modares University, Mazandaran
Landslide is among the natural disasters which cause many damages such as killing and wounding many peoples and lead to homelessness millions of households every year all over the world. The main objective of this research is making landslides susceptibility zoning, using Geospatial Information System (GIS) and probability model "weight of evidence" in limited areas of Haraz watershed located in Mazandaran province. Due to the mentioned objective, by using the field trip and aerial photographs interpretation, 78 landslide points were found and mapping of these landslides were prepared. The data informations about layers of slope, aspect, altitude, slope curvature, lithology, landuse, distance of river, distance of road, distance of fault, index of stream power, wetness index and sediment transport index were considered as effective factors on landslide events and then theirs maps were digited in GIS field. By using the laws of probability, relations among factors and landslides were considered and mapping of landslide sensitivity areas in region was prepared. Model assessment was carried out by one third of landslide points, SCAI index and ROC curve. The results showed a high correlation between dangerous map and landslide distribution. The probability model precision was estimated as very well (79.87 %) in study area. The most important innovation of this research, comparing to other researches conducted, is using the factors such as slope curvature, index of stream power, wetness index and sediment transport index, as well as simultaneous employing of two important methods for evaluating the model (SCAI index and ROC curve).
http://jgit.kntu.ac.ir/article-1-64-en.pdf
Landslide
Probability Theory
GIS
SCAI Index
ROC Curve
per
kntu
Engineering Journal of Geospatial Information Technology
2008-9635
2014-03
1
2
81
90
article
A New Method for Deformation Analysis of Vertical Networks
Gholam Reza Rezaee Javid
1
Masoud Mashadi Hossainali
hossainali@kntu.ac.ir
2
K.N.Toosi University of Technology
K.N.Toosi University of Technology
Analyzing the stability of reference points is a key problem in deformation analysis. The reason is that the instability of these points results in the erroneous interpretation of the deformation process. In this paper, the stability of points in a vertical network has been analyzed, using the given methods of congruency and minimum-making the first norm. Comparison of the obtained results proves that the two methods do not provide a unique solution for the problem. Considering the obtained contrary results and the need for the estimation of the absolute displacements of the network points, a new method has been developed. Using the mentioned method, which is based on the reformulation of the corresponding observation equations, makes possible to compute the absolute displacements of the network points with respect to a reference measurement epoch.
http://jgit.kntu.ac.ir/article-1-65-en.pdf
Deformation Analysis
Congruency Method
Minimum First Norm Method
Reference Epoch Method.
per
kntu
Engineering Journal of Geospatial Information Technology
2008-9635
2014-03
1
2
91
108
article
Accuracy Investigation of Analytical Hierarchy Process (AHP) and Multivariate Regression (MR) Methods in Landslide Hazard Zonation, Using GIS (Case Study: Marbor River Basin)
Kourosh Shirani
k_sh424@yahoo.com
1
Abdollah Saif
2
Masoud Alimoradi
3
University of Isfahan
University of Isfahan
University of Isfahan
A combination of natural and human factors have caused numerous landslide related damaged. One of the main strategies for reducing the damages of landslides is to avoid these regions. For this purpose it is necessary to be prepared landslide hazard zonation map precisely among available methods for these areas. At first, the object of this research is the relative weight determination of effective parameters, using Multivariate Regression (MR) in substitute of parameters priority in Analytical Hierarchy Process (AHP). For implementing this research, first of all, by aerial photos and satellite images, geological maps and studies of the field by using GPS, landslide inventory map in Marbor River Basin (sub-basin of the upper part of North Karoon Basin), an 800 square kilometers area located on the lower part of Southern Isfahan province, were prepared. By Using field studies and reviewing the related studies about similar areas with basins of Karoon and Dez Upper North and the existing thematic maps, 9 factors including lithology, slope, land use, rainfall, vegetation, aspect, and lineaments elements, containing fault and drainages, the action of factors in determining landslide (54 parameters in the consist of eight main factors) were measured. For the purpose of enhancing accuracy, accelerating and easing the analysis, all spatial and descriptive data entered into GIS system and were overlayed ArcGIS version9.3 software as vector. By overlaying these maps, 27466 homogeneous units were resulted, that were based upon calculating two methods including MR an AHP related to Multivariate decision analysis the results of analysis showed that both methods have almost had the same accuracy in separation landslide hazard zones, and the landslide hazard index was obvious too. Of course, it should be noticed that hierarchical approach based on regression data, on the basis the sum of quality index as an indicator of the accuracy, is more desirable.
http://jgit.kntu.ac.ir/article-1-66-en.pdf
Landslide
Hazard zonation
Marbor watershed
Multivariate regression
Analytical Hierarchy Process
GIS