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    A Customized Particle Swarm Method to Solve Highway Alignment Optimization Problem

    , Article Computer-Aided Civil and Infrastructure Engineering ; Volume 28, Issue 1 , January , 2013 , Pages 52-67 ; 10939687 (ISSN) Shafahi, Y ; Bagherian, M ; Sharif University of Technology
    2013
    Abstract
    Optimizing highway alignment requires a versatile set of cost functions and an efficient search method to achieve the best design. Because of numerous highway design considerations, this issue is classified as a constrained problem. Moreover, because of the infinite number of possible solutions for the problem and the continuous search space, highway alignment optimization is a complex problem. In this study, a customized particle swarm optimization algorithm was used to search for a near-optimal highway alignment, which is a compound of several tangents, consisting of circular (for horizontal design) and parabolic (for vertical alignment) curves. The selected highway alignment should meet... 

    Spatial analysis and mapping of malaria risk in an endemic area, south of Iran: A GIS based decision making for planning of control

    , Article Acta Tropica ; Volume 122, Issue 1 , 2012 , Pages 132-137 ; 0001706X (ISSN) Hanafi Bojd, A. A ; Vatandoost, H ; Oshaghi, M. A ; Charrahy, Z ; Haghdoost, A. A ; Zamani, G ; Abedi, F ; Sedaghat, M. M ; Soltani, M ; Shahi, M ; Raeisi, A ; Sharif University of Technology
    2012
    Abstract
    Bashagard district is one of the important malaria endemic areas in southern Iran. From this region a total of 16,199 indigenous cases have been reported in recent years. The aim of this study was to determine the situation of the disease and provide the risk map for the area. ArcGIS9.2 was used for mapping spatial distribution of malaria incidence. Hot spots were obtained using evidence-based weighting method for transmission risk. Environmental factors including temperature, relative humidity, altitude, slope and distance to rivers were combined by weighted multi criteria evaluation for mapping malaria hazard area at the district level. Similarly, risk map was developed by overlaying... 

    A GIS-google earth based approach to estimating the flood damage function in large river basins

    , Article World Environmental and Water Resources Congress 2011: Bearing Knowledge for Sustainability - Proceedings of the 2011 World Environmental and Water Resources Congress, 22 May 2011 through 26 May 2011 ; May , 2011 , Pages 3811-3821 ; 9780784411735 (ISBN) Abrishamchi, A ; Dashti, M ; Alamdari, N ; Salavitabar, A ; Sharif University of Technology
    2011
    Abstract
    Flood as a natural disaster causes heavy human and economic losses and social unrests in most areas of the world. As flood control cost and flood damage compensation is a heavy burden over countries' budget, traditional flood design methods are being replaced by more reliable risk-based methods employing comprehensive risk analysis. In this respect, flood damage estimation is an important step in flood control systems design and analysis. In large river basins with complex reservoir systems and various land uses, flood damage estimation is complex, data-intensive, time demanding, and uncertain task requiring an intensive hydrologic and hydraulic analysis. In this study a simple approach is... 

    Iran atlas of offshore renewable energies

    , Article Renewable Energy ; Volume 36, Issue 1 , January , 2011 , Pages 388-398 ; 09601481 (ISSN) Abbaspour, M ; Rahimi, R ; Sharif University of Technology
    2011
    Abstract
    The aim of the present study is to provide an Atlas of IRAN Offshore Renewable Energy Resources (hereafter called 'the Atlas') to map out wave and tidal resources at a national scale, extending over the area of the Persian Gulf and Sea of Oman. Such an Atlas can provide necessary tools to identify the areas with greatest resource potential and within reach of present technology development. To estimate available tidal energy resources at the site, a two-dimensional tidally driven hydrodynamic numerical model of Persian Gulf was developed using the hydrodynamic model in the MIKE 21 Flow Model (MIKE 21HD), with validation using tidal elevation measurements and tidal stream diamonds from... 

    A new hybrid model using step-wise weight assessment ratio analysis (SWARA) technique and adaptive neuro-fuzzy inference system (ANFIS) for regional landslide hazard assessment in Iran

    , Article Catena ; Volume 135 , 2015 , Pages 122-148 ; 03418162 (ISSN) Dehnavi, A ; Aghdam, I. N ; Pradhan, B ; Morshed Varzandeh, M. H ; Sharif University of Technology
    Elsevier  2015
    Abstract
    In recent years, Iran has experienced many landslides due to high tectonic activity, and a variety of geological and climatic conditions. This paper proposes a novel hybrid model based on step-wise weight assessment ratio analysis (SWARA) method and adaptive neuro-fuzzy inference system (ANFIS) to evaluate landslide susceptible areas using geographical information system (GIS). At first, based on an inventory map, landslide locations were randomly divided into two parts, 70% of which were used for generating the landslide hazard map and 30% of which were used for the validation of the model. Then, twelve landslide predisposing factors, such as lithology, slope angle, slope aspect, plan... 

    Forecasting Urban Groundwater Level Applying Geographical Information System (GIS) and Artificial Neural Network (ANN)

    , M.Sc. Thesis Sharif University of Technology Jazaei, Farhad (Author) ; Abrishamchi, Ahmad (Supervisor)
    Abstract
    Groundwater beneath the cities is becoming an important and valuable resource. Conjunctive use of surface and groundwater is likely to become increasingly more common as urban population grows by time. Therefore, one important requirement for urban water management planning is forecasting the groundwater level fluctuations. Unfortunately less experience and information is available to evaluate the fluctuations of groundwater level in urban environment compare to the natural systems, also different processes (sources) are involved in an urban water cycle, which all together make it more complicated to study. Similar to many other megacities, there is a serious lack of hydrogeological and... 

    Development of a Model to Investigate Energy Production Potential from Sea Applying GIS Technique

    , M.Sc. Thesis Sharif University of Technology Rahimi, Rahman (Author) ; Abbaspour, Majid (Supervisor)
    Abstract
    The growing requirements for renewable energy production lead to the development of a new series of systems, including wave and tidal energy conversion systems. Due to their sensitivity and the impact of the aggressive marine environment, the selection of the most adequate location for these systems is a major and very important task. Several factors, such as technological limitations, environmental conditions, administrative and logistic conditions, have to be taken into account in order to support the decision for best location. The aim of the present study is to provide an Atlas of IRAN Offshore Renewable Energy Resources (hereafter called ‘the Atlas’) to map out wave and tidal resources... 

    An Innovative Method to Monitor Power Production Performance of Wind Farms Using Web-GIS Technique

    , M.Sc. Thesis Sharif University of Technology Pouryousefi, Ali (Author) ; Abbaspour, Madjid (Supervisor) ; Mehdigholi, Hamid (Co-Advisor)
    Abstract
    Nowadays because of population growth and limitation of fossil fuels for power generation purpose, utilization of renewable energy sources has become highlighted. According to the geographical situation for use of wind energy, since some areas of Iran are in suitable conditions the manufacture of wind turbines and installation in wind farms has been under development recently. Monitoring the performance and operation of turbines and wind farms is an inevitable matter. Because of the suitable geographical location of Iran and pursuant to fair wind potential sites widespread this country, this phenomenon requires some backgrounds in many aspects to be achieved. One of the most important... 

    A New Representation for GIS Data Based on Vector Format

    , M.Sc. Thesis Sharif University of Technology Meskar, Ahmad (Author) ; Vosughi Vahdat, Bijan (Supervisor) ; Bagheri Shouraki, Saeed (Co-Advisor)
    Abstract
    One of the important tools that we frequently use in life is the map. In every day movements we can use the maps in order to navigate and find our way. We also utilize the maps to find out more about our surrounding world. GIS is the key technology which can help us reach these goals. In GIS generally there are 2 methods for representing geographic data, these methods are Raster and Vector data representation. In this thesis our purpose is to find another way for representing GIS data by using vector format. In this new representation we can access to information which are not accessible in regular maps. So we generate a new flexible platform for GIS data. Thus in order to represent new... 

    A logit-based model for facility placement planning in supply chain management

    , Article International Journal of Logistics Systems and Management ; Volume 20, Issue 1 , 2015 , Pages 122-147 ; 17427967 (ISSN) Bagloee, S. A ; Shnaiderman, M ; Tavana, M ; Ceder, A ; Sharif University of Technology
    Inderscience Enterprises Ltd  2015
    Abstract
    The facility placement in supply chain management entails suppliers and consumers along with the terminals in between for distributing commodities. This study seeks to find the best terminal placement by taking into consideration the costs for both transportation and terminal construction. We call this a supplier-terminal-consumer (STC) problem and show that the STC is an NP-hard quadratic assignment problem. The NP-hard problems in real-size are proven to be intractable; hence, we develop a two-fold heuristic method for solving the STC problems. First, we identify the commodity flow by using a logit-based mathematical programming (Logit-MP) methodology based on the demand for the commodity... 

    Study and Assessment of Groundwater Vulnerability and Contamination to Nitrate: A Case Study of Mashhad City

    , M.Sc. Thesis Sharif University of Technology Asadi, Parisa (Author) ; Ataie-Ashtiani, Behzad (Supervisor)
    Abstract
    Groundwater resources in arid and semi-arid regions, which the most parts of them have not had enough surface water, is of great importance. Due to the paramount importance of these vital resources, many scholars have conducted various studies on groundwater contamination and, especially, on nitrate as the best indicator of groundwater contamination because of its ability to transport, its low absorption, and its durability in water. In this study, using qualitative methods, groundwater contamination of Mashhad aquifer was evaluated, and then in order to obtain better adjustment with urban areas, these methods were modified which resulted in better correlation with measured nitrat. Based on... 

    Fabrication of gas ionization sensor using carbon nanotube arrays grown on porous silicon substrate

    , Article Sensors and Actuators, A: Physical ; Volume 162, Issue 1 , 2010 , Pages 24-28 ; 09244247 (ISSN) Nikfarjam, A ; Iraji Zad, A ; Razi, F ; Mortazavi, S. Z ; Sharif University of Technology
    2010
    Abstract
    We fabricated gas sensors based on field ionization from multiwalled carbon nanotube (MWCNT) arrays grown on porous silicon templates. MWCNTs were grown through thermal chemical vapor deposition. We measured breakdown voltages, discharge and pre-discharge currents of the device for various gases in different concentrations. Our gas ionization sensors (GIS) presented good sensitivity, selectivity and short response time. The GISs based on porous substrates showed higher discharge current and good mechanical stability in comparison to those which were fabricated on polished silicon substrates. Additionally, we applied a high electric field to align CNTs. This increased the pre-breakdown... 

    Finding paths with minimum shared edges

    , Article Journal of Combinatorial Optimization ; Volume 26, Issue 4 , 2013 , Pages 709-722 ; 13826905 (ISSN) Omran, M. T ; Sack, J. R ; Zarrabi Zadeh, H ; Sharif University of Technology
    Abstract
    Motivated by a security problem in geographic information systems, we study the following graph theoretical problem: given a graph G, two special nodes s and t in G, and a number k, find k paths from s to t in G so as to minimize the number of edges shared among the paths. This is a generalization of the well-known disjoint paths problem. While disjoint paths can be computed efficiently, we show that finding paths with minimum shared edges is NP-hard. Moreover, we show that it is even hard to approximate the minimum number of shared edges within a factor of 2log1-εn, for any constant ε>0. On the positive side, we show that there exists a (k-1)-approximation algorithm for the problem, using... 

    Finding paths with minimum shared edges

    , Article Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), 14 August 2011 through 16 August 2011 ; Volume 6842 LNCS , August , 2011 , Pages 567-578 ; 03029743 (ISSN) ; 9783642226847 (ISBN) Omran, M. T ; Sack, J. R ; Zarrabi Zadeh, H ; Sharif University of Technology
    Abstract
    Motivated by a security problem in geographic information systems, we study the following graph theoretical problem: given a graph G, two special nodes s and t in G, and a number k, find k paths from s to t in G so as to minimize the number of edges shared among the paths. This is a generalization of the well-known disjoint paths problem. While disjoint paths can be computed efficiently, we show that finding paths with minimum shared edges is NP-hard. Moreover, we show that it is even hard to approximate the minimum number of shared edges to within a factor of 2log1-εn, for any constant ε > 0. On the positive side, we show that there exists a k-approximation algorithm for the problem, using... 

    Design of Water Conveyance Systems Route Applying Satellite Images, Geographic Information System(GIS) & Genetic Algorithm

    , M.Sc. Thesis Sharif University of Technology Ghasemi, Abazar (Author) ; Shamsai, Abulfazl (Supervisor)
    Abstract
    To reduce construction costs selecting the optimal route for water conveyance line entails ample observation and considering all effective parameters. Some part of Aidoghmoush dam project of water conveyance line located in Azerbijan the east has been investigated in this research. First, by investigating, effective factors in determining the optimal route have been identified and then categorized into two groups of quantitative criteria(technical-economical) and qualitative criteria(environmental). Quantitative objectives include: slope, transportation system, infrastructures, fault and soil type. Qualitative objectives include: environmental considerations, land use and land cover. Because... 

    Offline Map-Matching for GPS Observations

    , M.Sc. Thesis Sharif University of Technology Dobash, Ashkan (Author) ; Abam, Mohammad Ali (Supervisor)
    Abstract
    Location observations from Global Positioning System (GPS) loggers are an important source of data for travel behavior researchers. Using GPS, requires a receiver, a digital map and a software that matches the user logged positions to the map. Identifying the location of the GPS data points on a coded map of the transportation network is not a trivial process. There is always an error in calculating the coordinates obtained from the GPS satellites, and also the available maps are not accurate enough. As a result, map-matching always carries some errors. Thus, different algorithms to do this mapping more precisely are presented. The output of the map-matching process is the identification of... 

    Ant colony optimisation for finding the optimal railroad path

    , Article Proceedings of the Institution of Civil Engineers: Transport ; Volume 170, Issue 4 , 2017 , Pages 218-230 ; 0965092X (ISSN) Hasany, R. M ; Shafahi, Y ; Sharif University of Technology
    Thomas Telford Services Ltd  2017
    Abstract
    Engineers have applied mathematical models to find the optimal railway path in order to minimise the total cost subject to the railway limitations. There are two main issues for this problem. First, this approach results in a complex formulation for real-life applications, mainly because there are a huge number of variables and constraints. Second, to compute the total cost, different types of data are required, such as topography, right-of-way unit cost, forbidden zones and geology. Because various administrations are often responsible for preparing these data with their own standards, there is much inconsistency in the data. This paper deals with the first issue by proposing a... 

    Integrating spatial multi criteria decision making (smcdm) with geographic information systems (gis) for delineation of the most suitable areas for aquifer storage and recovery (asr)

    , Article Journal of Hydrology ; Volume 551 , 2017 , Pages 577-595 ; 00221694 (ISSN) Ahani Amineh, Z. B ; Hashemian, S. J. A.D ; Magholi, A ; Sharif University of Technology
    Elsevier B.V  2017
    Abstract
    Hamoon-Jazmoorian plain is located in southeast of Iran. Overexploitation of groundwater in this plain has led to water level decline and caused serious problems such as land subsidence, aquifer destruction and water quality degradation. The increasing population and agricultural development along with drought and climate change, have further increased the pressure on water resources in this region over the last years. In order to overcome such crisis, introduction of surface water into an aquifer at particular locations can be a suitable solution. A wide variety of methods have been developed to recharge groundwater, one of which is aquifer storage and recovery (ASR). One of the fundamental... 

    Hydropower plant site spotting using geographic information system and a MATLAB based algorithm

    , Article Journal of Cleaner Production ; Volume 152 , 2017 , Pages 7-16 ; 09596526 (ISSN) Serpoush, B ; Khanian, M ; Shamsai, A ; Sharif University of Technology
    Abstract
    Meanwhile with increasing demand for energy sources in the world, hydropower plants can be considered as clean energy sources for sustainable development. Hydropower plant environmental impact is almost none. They are easy to construct and operate with much lower cost in comparison with other types of power plants. Currently in Iran, Conventional methods for determining hydropower plant potent location are very complicated and do not always eventuated to the best result. This study focuses on run of river projects and proposes a new methodology to spot hydropower plan best location according to specific engineering criteria, using ArcGIS and an algorithm developed in MATLAB. An economic... 

    Vulnerability assessment of urban groundwater resources to nitrate: the case study of Mashhad, Iran

    , Article Environmental Earth Sciences ; Volume 76, Issue 1 , 2017 ; 18666280 (ISSN) Asadi, P ; Ataie Ashtiani, B ; Beheshti, A ; Sharif University of Technology
    Springer Verlag  2017
    Abstract
    Groundwater vulnerability assessment of urban areas is a challenging task in the fast trend of urbanization around the globe. This study introduces a new approach for modifying well-known parameters of common vulnerability indexes to adjust them for urban areas. The approach is independent of a specific weighting system. The aquifer of Mashhad city, contaminated by domestic wastewater, is selected as a case in this study. In order to evaluate the aquifer vulnerability due to anthropogenic activities, at first, parameters of depth to groundwater, recharge, land use, and soil are modified based on their basic concepts and their influences on contamination attenuation. Then, the modified...