Mohammad Fallah Zazuli; Alireza Vafaei Nezhad; Ali Asghar Alesheikh; Mahdi Modiri; Hossein Aghamohammadi
Abstract
Extended Abstract Introduction Landslide is one of the most important types of natural disasters,which endangers lives and financial security of many people and destroys environment and natural resources.With the present population growth and expansion of urban areas towardsteep areas and hillsides, ...
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Extended Abstract Introduction Landslide is one of the most important types of natural disasters,which endangers lives and financial security of many people and destroys environment and natural resources.With the present population growth and expansion of urban areas towardsteep areas and hillsides, landslide-related losses can be catastrophic. For an instance, landslides in Badakhshan Province in Afghanistan killed around 2,700 people in 2014, and a landslide in China (Shan’xiprovince)resulted in the disappearance of 64 people in 2015.Therefore, assessingthe possibility of landslides occurrence seems to becrucial. Providing zoning maps is one of the measures which makes identification of areas prone to future landslides possible. Inferences drawn from these maps can be used for land use planning, prevention of unauthorized construction activities, infrastructure development, refurbishment and restoration. Materials & Methods The present research selectsEast Rudbar-e Alamut (a district of Qazvin province), which is affected by landslides and instability of hillsides, as the study area. It takes advantage of Shannon entropy and information value models to develop landslide susceptibility map of the study areain GIS environment.Shannon entropy theory has been used in extensive researcheswith the aim of prioritizinginfluential factors in the probable occurrence of natural disasters such as landslide. Information value (IV) model is one of the statistical models drawn from information theory with a widespread application in the modeling of geological hazards and disaster risk assessment. Information value model aims to find a combination of significant factors anddeterminetheir impacton theoccurrence oflandslide in an area.To implement this model, relevant data and its related criteria maps were prepared. In this regard, the location of previous landslide events in the study area was determined based on the information received from Forests, Range and Watershed Management Organization. 49 landslides were identified in this way. Then, data was randomly divided into 2 categories: training data and validation data. Thus, 70% of data (35 landslides) were used to produce the models and the remaining 30% (14 landslides) were used for validation purposes. In addition to previous landslides, a collection of topographic, environmental and climatic characteristics of the study area including seven criteria of lithology, slope, distance from faults, land use, precipitation, slope-direction and elevation were selected as the most effective independent variablesto produce criteria maps with 30-meter spatial resolution. Basic information used to map these seven influential factors was obtained from Forests, Range and Watershed Management Organization, as well as the SRTM Digital Elevation Model (DEM), and used after some modifications. Considering the capability of ArcGIS in spatial data analysis, thissoftwarewas used to produce information layers and implement the models. Results & Discussion Prioritizing influential factors using Shannon entropy model introducesthree factors (i.e. land use, elevation and precipitation)as the most significant factorsin the occurrence of landslides in the study area. Factors of slope angle, distance from faults (almost equal to slope angle), lithology and slope-direction were in the next influential factors.Also, results of information value model indicate that looking from lithology perspective, the category of marl, calcareous sandstone, sandy limestone and minor conglomerate has an information value of 1 and thus, the highest probability of landslide occurrence. Category of basaltic volcanic rocks, along with category of well bedded green tuff and tuffaceous shale have the lowest probability of landslide occurrence with information values of -2.03 and -1.70, respectively.Only two categories of theslope angle criterionhave a positive-index. The highest information value (0. 93) in this category occurs in the class of 5-12 degrees, followed by the class of 12-20 degrees. The lowest information value occurs in slopes of more than 30 degrees. Based on this observation, it can be clearly concluded that the slope angles of 5 to 20 degrees are most prone to landslides. Distance to faults criterion indicate that the category of500 to 1000-meter distance to faultshave the highest information value (1.67). Regarding land use criterion, three land uses of garden, agriculture and garden-agriculture have the highest information values of 2.16 and 1.59 and 1.11, respectively. Regarding precipitation, average annual rainfall of less than 400 millimeters have the highest information value (1.50). Regardingslope-direction criterion, most landslides occur in southwest, south and eastdirections.Northeast, west, and northwest directions have the lowest probability of landslide occurrence, respectively. In terms of elevation, the information value is reduced as the height increases, and the maximum information value is related to the elevations of less than 1200 meters.After assigning a weight to each criterion and related classes, the landslide risk zone map was generated based on Shannon entropy and information valuemodels. The resulting zoning map produced based on natural breaks methods dividesthe area into five classeswith very high, high, moderate, low and very low risk. Resultsof Shannon entropy modelindicate that out of 14 landslides considered as the validation data, 3, 7, 2, 1, 1 landslideshave occurred in very high, high, moderate, low and very low risk zones, respectively. Resultsof the information value modelindicatethat 8, 4, 0, 1, 1 landslideshave occurred in very high, high, moderate, low and very low risk zones, respectively. Conclusion Evaluation of results using experimental probability index indicates that with 86% experimental probability,both models of Shannon entropy and information value are effective inidentification of landslide hazard in the East Rudbar-e Alamut region. Also, considering the number of landslides in very high and high risk zones, Shannon entropy and information value modelshave an experimental probability index of 72% and 86%, respectively, which prove higher efficiency of information value model. In Shannon entropy model, total area of very high, high and moderate risk zones covers 34% and 56% of the study area,respectively. In information value model,total area of very high and high risk zones covers 20% and 29% of the study area, respectively. Based on the landslide risk zone map, high and very high risk zones are mainly located in the west of the study area.
Hekmatollah Mohammad Khanlu; Mahdi Modiri; Elahe Khesali; Hamid Enayati
Abstract
Introduction
Hydrography is a science used for regular measurement of parameters such as depth of water, geophysical geology, tide, water flow, waves and other physical properties of seawater. It is also used for the production of maritime maps. Hydrography contributes significantly to the internal ...
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Introduction
Hydrography is a science used for regular measurement of parameters such as depth of water, geophysical geology, tide, water flow, waves and other physical properties of seawater. It is also used for the production of maritime maps. Hydrography contributes significantly to the internal infrastructure of coastal countries. Providing proper hydrographic services ensures safe and efficient sailing. Thus, development of hydrographic services on the national level can improve safety of mariners, and protect people’s lives and belongings on the sea, while providing some facilities for the protection of marine environment. The advancement of space technologies in recent years has increased the speed of spatial information production and facilitated sea monitoring.
Materials and Methods
Different methods are used for bathymetry. Lyzanga et al (1978) used a linear combination of the logarithm of corrected radiance ratio. This method is based on the simplification of Beer's physical model in which a linear equation of five unknowns is obtained for two bands. In 2006, Lyzanga et al. presented an improved version of their model. Using Tow-Bands Reflection Ratio, Stampf et al (2003) not only reduced the number of unknown variables in Lyzenga method, but also decreased the sensitivity of depth determination to different substrates. In this method, the difference between absorption properties of green and blue bands is used. TCarta is a global supplier of geospatial products. The company generated Satellite Derived Bathymetry (SDB) dataset by accurately extracting water depth from multispectral imageries received from the European Space Agency’s Sentinel-2 Satellite. The resulting bathymetric data had a point spacing of 10 meters, while measuring up to a depth of 15 meters. Data covered a 30-square kilometer area around Preparis Island on the Bay of Bengal.
The present article used images received from Sentinel-2 in 7 different periods for depth determination, and 1: 25,000 ADMIRALTY Nautical Charts for accuracy evaluation. Following the assessment of water transparency in received images, the 12/15/2018 image was used for depth determination. Case study area contains around 130 km along the Port of Salalah, Oman.
Results and Discussion
In order to implement the model, it is necessary to separate land from water in images using NDVI, NDWI, MNDWI and AWEI indices. The NDVI index has been used in this project. NDVI is primarily used to estimate vegetation cover, but since this index exhibits a negative value in areas covered with water, this property is used to provide a mask for separating land from water. In this step, 68 control points and 68 check points were selected from the existing ADMIRALTY map. The DN values of the corresponding pixels of the selected points were extracted from four 10-meter bands of Sentinel-2 images. The control and checkpoints and the DN value of their corresponding pixels were extracted in 4 separate files, then these 4 files were logged into the Bathymetry software and the parameters of LMR and Stumpf methods were calculated. The root mean square error (RMSE) and correlation coefficient (CC) were used to assess geometric accuracy. In order to extract necessary parameters for each model, RMSE= 2.15 m and CC= 92.5% were calculated at depth distances of 0 to 20m. Results indicates higher accuracy and stronger correlation of LMR findings. Therefore, this method was used for depth determination between 0 to 20 meters. The 5 parameters extracted from the Bathymetry software and the corresponding pixel values of the four bands with 10-meter resolution extracted from the Sentinel-2 image (received from the on 12-15-2018) were used as input. Linear Regression Model was applied to transform 4 bands of Sentinel-2 image into depth. The output of the model (depth) was presented as the Substrate DEM of the coasts of Port of Salaleh, Oman.
Conclusion
Hence, it can be concluded that Remote Sensing technologies can be used for depth determination and sea monitoring at critical times (during wars or other periods of insecurity) for an acceptable time period. It also provides an appropriate context for bathymetry of inaccessible coastlines and monitoring of strategic widespread water zones. In this way, the depth of sea bed in shallow areas is extracted using spectral analysis of satellite data and different models.
Mahdi Modiri
Volume 3, Issue 9 , January 2018, , Pages 2-4
Abstract
For easy understanding and quick access, all types of geographic information are displayed on maps, because displaying information graphically is, in many cases, more indicative than a number of books on the same matter. Any modification or revision of information in maps requires development of a new ...
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For easy understanding and quick access, all types of geographic information are displayed on maps, because displaying information graphically is, in many cases, more indicative than a number of books on the same matter. Any modification or revision of information in maps requires development of a new map with a process similar to that of the first map. In fact, the information on map is not always exploited and sometimes finds only quantitative value as archives.
Ahmad Pourahmad; Hossein Hataminejad; Mahdi Modiri; Ashraf Azimzadeh Irani
Abstract
Introduction
Preservation and maintenance of historical urban fabrics or fabrics containing cultural heritage of cities is of special importance, because these fabrics, in addition to creating a sense of identity and stimulating national pride, improve the citizens' quality of life. "Improvement"is ...
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Introduction
Preservation and maintenance of historical urban fabrics or fabrics containing cultural heritage of cities is of special importance, because these fabrics, in addition to creating a sense of identity and stimulating national pride, improve the citizens' quality of life. "Improvement"is one of the methods and, of course, the most appropriate one, of intervention in the historical fabrics of cities, because in this type of intervention, the principle is based on "loyalty to the past and the preservation of identity-stimulating effects".
Improvement activities are aimed at using available potential and actual facilities, strengthening positive aspects and weakening negative ones. In each of the improvement measures, no significant intervention is performedin the physical aspect, and only by replacing the proper functioning of activity, the erosion of this type of urban space is prevented, and by making changes in urban activities, favorable urban spaces are created. Since the observance of the "passive defense requirements" as well as the "sustainable urban development principles" is an essential requirement in selecting the appropriate pattern for the improvement of the old urban fabric, the study of the principles governing these two concepts indicates thatcontradictions exist between these principles. In the present study, we have mainly studied and examined these two important and influential concepts on the improvement patterns of historical urban fabric, and carried out a comparative study of the principles governing them. The purpose of this research is to outline the contradictions between the requirements of passive defense and the principles of sustainable urban development in the improvement pattern of urban historical fabric and to find a suitable solution in this regard.
Materials & Methods
The research method was applied in terms of the aim, and descriptive-exploratory in terms of conduct. The data gathering method was both documentary (secondary) and field surveys, and analyses were performed using the ArcGIS software and also by the Paired Comparison Analysis method. The historical fabric of the 12th district of Tehran, with an emphasis on the historical element of the museums, was the case study of this paper, which made it possible to achieve the results of the research. In order to prioritize some uses in positions where the studied historical element (museum) are located, from the point of view of passive defense as well as from sustainable urban development perspective, we can use the Paired Comparison Analysis method to achieve the most balanced result, so that the conflict between the two approaches is not significant. First of all, the importance of each single studied use is examined from either of the two perspectives through the spatial analysis ofthe position of that particular use relative to the location of the museums. Then, the view of passive defense concerning each use has been compared with that of sustainable urban development according to the relevant criteria, and scored on the basis of importance.
Results & Discussion
The results of the research show that, in order to find the most suitable pattern of intervention - of improvement type - in the historical fabric, it is necessary that along with emphasis on the requirements of passive defense and principles of sustainable urban development, we must, in addition to prioritizing changes in uses, reduce the grounds for the creation of any kind of contradiction in approaches. Therefore, in the present paper, the uses and elements affecting theregion have been analyzed in relation to the studied fabric (museums). In the investigated pattern, actions and predictions to improve the physical and spatialquality of environment through the replacement of proper operation of activity will prevent the erosion of the historical urban fabric, and by creating changes in urban activities, favorable spaces for the protection of historical fabric will be created.
Conclusion
In spite of the proof of the conflict between "passive defense requirements" and "principles of sustainable urban development", the emphasis on both concepts in the improvement pattern of city’s historical fabric isinevitable.
Therefore, by adopting an appropriate model for improvement and appropriate methods of intervention, it is possible to perform the important task of preserving the historical fabric by optimally changing some of the uses.
Ali Kalantari Oskouei; Mahdi Modiri; Ali Asghar Alesheikh; Reza Hosnavi
Abstract
Abstract
The main objective of this research was to determine Iran’s National Spatial Data Infrastructures (NSDI) readiness index, with the aim of identifying the basic restrictions that impede NSDI development. The framework of the research is constructed on the basis of survey and SDI readiness ...
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Abstract
The main objective of this research was to determine Iran’s National Spatial Data Infrastructures (NSDI) readiness index, with the aim of identifying the basic restrictions that impede NSDI development. The framework of the research is constructed on the basis of survey and SDI readiness model. In this research, Iran’s NSDI based on this fuzzy-based model has been assessed using 16 decision-making criteria in the form of five organisational, human resources, data and information, technological and financial factors.The required data for the research were collected through the questionnaire and interview with the experienced experts from the government agencies, Universities, and private sector of the country who were familiar with the spatial data infrastructure. The results of the implementation of the model demonstrated that Iran’s NSDI readiness composite index was 0.44. In addition, the assessment of the factors of Iran’s NSDI readiness showed that all of them, with the exception of the technology factor, were less developed. Moreover, the status of 75% of decision-making criteria was not satisfactory. In this research, the state of investment of the government and the private sector, communication infrastructure, organizational and individual leadership, legal issues, politicians' perspective, metadata, culture and education regarding the spatial data infrastructure were recognized as the most important limiting measures in the establishment of the NSDI. In spite of numerous factors inhibiting the development of NSDI, the status of criteria for connecting to the Web, access to data and digital spatial data, human capital, and access to geospatial software were evaluated at an appropriate level of development. Also, according to the results of this research, it seems that in the development of the NSDI, non-technical issues (organizational, human resources, and financial factors) can play a role as a limiting factor than technical issues (technological factor). At the end of the paper, recommendations have been presented to resolve the country’s NSDI development constraints.
Mahdi Modiri
Volume 22, Issue 88 , January 2014, , Pages 2-46
Abstract
Explicators believe that noble verses of Surah Al-‘Alaq were among the first verses revealed to the holy prophet of Islam. According to Surah Al-‘Alaq, teaching by pen is considered to be among the God’s attributes (Recite, and your Lord is the most Generous, Verses 3-4). To have a ...
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Explicators believe that noble verses of Surah Al-‘Alaq were among the first verses revealed to the holy prophet of Islam. According to Surah Al-‘Alaq, teaching by pen is considered to be among the God’s attributes (Recite, and your Lord is the most Generous, Verses 3-4). To have a creative and uplifting pen, we have to get acquainted with the value of pen and its high mission. Islam has been revealed to lead human being to peace and friendship, so that human use the pen committedly, travel in the way of perfection, and organize his/her mundane and spiritual life in the light of discovering the world truth and exploring the divine knowledge. Pen expresses human attitudes, beliefs and his understanding of the universe, and thus nurtures and flourishes his logic. Human being contemplates about the system of creation to create an effective work and a lasting memorial. Therefore, pen should be considered as a translation of human mind and heart and a tool for their flourishing and lasting (Nun. By the pen and what they inscribe, Surah Al-Qalam-1). In fact, pen is the original source of all civilizations, development and evolution of sciences, awakening of thoughts and source of guidance and awareness, to the extent that human history is divided into two era: pre historical and historical period. Historical period begins when writing was invented and human being could write down his life adventures. In other words, this is the period in which human starts writing and leaves “what they inscribe”. Pen is the protector of sciences, guardian of thoughts of thinkers, the intellectual connection loop of scholars, the bridge between human past and present, and even the earth and the heavens are also related by pen and tablet. In a system whose culture is its most obvious identity, endeavoring to write, compile and research is the finest and most humanistic form of collective participation. Sepehr has endeavored to take influential scientific and technical steps to develop geography and geomatics and provide necessary conditions to realize exchange of scientific achievements between scholars, teachers and students. With the God’s beneficence, guidance of the editorial board, teachers, scholars and investigators in the armed forces, universities, higher education centers, enthusiasts, and collective efforts of scientific and technical board, Sepehr journal has created an appropriate environment for scientific conversation.
Mahdi Modiri; Reza Aghataher; Mohammad Fallah Zazuli; Mohsen Jafari
Volume 22, Issue 86 , June 2013, , Pages 5-16
Abstract
Effective planning and decision-making require access to accurate and updated information. Having updated spatial information and proper application of it is one of the most important topics in the command. A C4I system is composed of several smaller systems that can help military commanders assess the ...
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Effective planning and decision-making require access to accurate and updated information. Having updated spatial information and proper application of it is one of the most important topics in the command. A C4I system is composed of several smaller systems that can help military commanders assess the enemy’s information and make better decisions. Geospatial Information System )GIS( can assist commanders in achieving more rational decisions. GIS by modeling the Earth and the effect on Earth will provide a good view of the operating area for military commanders. This article reviews the role and application of Geospatial Information System in development of command and control.Using of new technologies such as mobile Geospatial Information System )Mobile GIS( and web-based Geospatial Information System )WEB GIS(, followed by locating the best places with different functions are GIS capabilities in command and control )C4I(.Thus, using Geospatial Information System capabilities by modeling of the operating area can be reached the highest rates in optimal and valid decisions for command and control.
Mahdi Modiri; Zahra Alibakhshi; Faramarz Khoshakhlaq; Ali Hanafi
Volume 21, Issue 84 , February 2013, , Pages 7-20
Abstract
In order to recognize the effective synoptic system in creation of moderate and severe frosts in Tehran and the conditions under which sever and moderate storms transform into one another, synoptic analysis has been implemented by mean sea level 850 and 700 hp maps in a period of 45 years (1961-2005). ...
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In order to recognize the effective synoptic system in creation of moderate and severe frosts in Tehran and the conditions under which sever and moderate storms transform into one another, synoptic analysis has been implemented by mean sea level 850 and 700 hp maps in a period of 45 years (1961-2005). The synoptic results indicated that the transformation of moderate frost into severe and exterminator frost is because of cold weather advection from higher latitude, setting of through over region or earthly radiation. Surveying 850 hp maps, it was recognized that decreasing of temperature in research region arises from the cold advection of various systems from northwest to northeast. In mean sea level maps, extension of Siberian high pressure ridge, and in 700 hp level, setting of through over the eastern part of the district has the most frequency and share in moderate and severe frost formation.
Mahdi Modiri
Volume 21, Issue 83 , November 2012, , Pages 2-8
Abstract
Earth has many different characteristics and measuring its physical features is a key step in many applications. With the development of different sensors, measuring different aspects of these phenomena has been made possible. With these sensors, we can collect necessary data considering different objects ...
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Earth has many different characteristics and measuring its physical features is a key step in many applications. With the development of different sensors, measuring different aspects of these phenomena has been made possible. With these sensors, we can collect necessary data considering different objects and reach useful information by their processing.
Satellite imagery is used in different applications as an economic and easily accessed digital information resource. Multi-spectral and hyperspectral imageries make an important part of satellite imageries. Multi spectral images are produced by sensors which calculate energy reflected from ground surface just in a few bands of electromagnetic spectra. Images produced by hyperspectral sensors measure reflected radiations in a series of long and connected bands. Hyperspectral sensors are the most powerful imaging sensors regarding spectral resolution and their images consist of information in more than 100 spectral bands.
Mahdi Modiri
Volume 21, Issue 82 , September 2012, , Pages 2-6
Abstract
Imageries received from aerial hyperspectral or satellite sensors record reflected data from earth surface in more than a hundred spectral bands. Hyperspectral imageries are used in different applications and different methods have been proposed and developed to extract data from these imageries. Diagnosing ...
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Imageries received from aerial hyperspectral or satellite sensors record reflected data from earth surface in more than a hundred spectral bands. Hyperspectral imageries are used in different applications and different methods have been proposed and developed to extract data from these imageries. Diagnosing inconspicuous features or anomaly detecting is one of the most important methods in extracting data from hyperspectral imageries.
The basic idea in designing hyperspectral sensors is based on the response each element shows in different sections of electromagnetic spectrum. Each element shows a specific reflective response in different sections of electromagnetic spectrum based on its own molecular structure. Different elements and materials show unique reflective response in similar situations.
Hyperspectral imageries have diverse and varied applications, among which we can refer to environmental monitoring, agricultural application, identifying unexpected events, geology, mines exploration and urban and regional studies.
Mahdi Modiri
Volume 21, Issue 81 , April 2012, , Pages 2-8
Mahdi Modiri
Volume 20, Issue 80 , February 2012, , Pages 2-6
Abstract
Simulation is the most appropriate urban design and planning environment and presents a unique field of study in urban models in urban development projects. The use of mathematics and quantitative and qualitative models has always been a concern for urban planners. Modeling phenomena and urban dynamic ...
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Simulation is the most appropriate urban design and planning environment and presents a unique field of study in urban models in urban development projects. The use of mathematics and quantitative and qualitative models has always been a concern for urban planners. Modeling phenomena and urban dynamic elements is usually confronted with technological constraints and difficulties. Each of the graphical models (structural and vector-based models) has some shortcomings in the simulation of dynamic urban phenomena. This paper intends to examine the limitations of cell-axis models in a simulation system and provide a new model for integrating vector-based spatial model with the cellular system.
Mahdi Modiri
Volume 20, Issue 79 , November 2011, , Pages 2-8
Abstract
Decision-making is the most important challenge facing experts and specialists in solving the problems of broad urban and regional planning. Multi-criteria decision-making issues usually include a set of location situations that should be evaluated based on several different criteria. Group approach ...
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Decision-making is the most important challenge facing experts and specialists in solving the problems of broad urban and regional planning. Multi-criteria decision-making issues usually include a set of location situations that should be evaluated based on several different criteria. Group approach considers decision making as an evolutionary process, which uses discussion, argumentation, and consensus of a discussion to describe question. The logic of the survey is to conduct a collective decision in an environment. In order to effectively support group participation in decision making, the tools of analysis and collaboration should be integrated and consistent. In connection with the importance and role of decision making, various methods have been introduced to support decision making and their efficiency and effectiveness have always been considered. The processes and analyses of multi-criteria decision making in GIS can be considered as a process that combines location data and evaluation values together.
Mahdi Modiri
Volume 20, Issue 78 , August 2011, , Pages 1-6
Abstract
Methods and tools for decision making by group participation come from different sources. These sources include work on the development of geographic information systems with the aim of improving the decision support capabilities, the technology of group support systems, and theoretical and empirical ...
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Methods and tools for decision making by group participation come from different sources. These sources include work on the development of geographic information systems with the aim of improving the decision support capabilities, the technology of group support systems, and theoretical and empirical studies of its application. Other sources include work on the collecting, The dynamism of logical methods, the research on the human dimensions of groupware and computer network, and GIS reviews as positivist attitudes, the constraints of opinions may lead to the expansion of the discussion and the discourse of decision-making. The enumerated sources provide a variety of decision-making theories that can be generalized as a group-analytic approach. An analytical approach uses mathematical models for structural sections of the decision-making problem, and leaves the non-structural parts to the decision-makers’ discretion. The group approach considers decision making as an evolutionary process, which uses discussion, argumentation, and consensus to explain a non-structured dialogue. The logic of the survey is that both approaches are necessary in a group decision support environment, and in order to effectively support group participation in decision making, analytical tools and collaboration tools must be combined and integrated. In this paper, different types of methods and tools are presented for group decision. Methods and tools for decision making through group participation result from many sources. These sources include working in order to expand GIS with the goal of improving decision support capabilities.
Mahdi Modiri
Volume 20, Issue 77 , May 2011, , Pages 2-9
Abstract
The production of urban maps by photogrammetric method, utilizing the automation of all stages and processes, including relative justification, is very important. Despite the many advances made in digital photogrammetry, there is still no reliable way to perform automatic relative justification operation ...
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The production of urban maps by photogrammetric method, utilizing the automation of all stages and processes, including relative justification, is very important. Despite the many advances made in digital photogrammetry, there is still no reliable way to perform automatic relative justification operation (ARO) on large-scale images of urban areas. In many research and development centers in the world, extensive efforts are being made to secure a consistent formulation for the matching of mapping process. Here, a method is examined and suggested that is special in some ways and is done using linear shear and edge features, surface correspondence and relative justification. This method, in the situation where the correspondence is normal, estimates the parameters of the mathematical model for the feature of two data sets of the feature. When relative justification is used, a single-page model is used to connect the pixels of the selected edges, or, a pair of consecutive images is used for the points of features. In implementing this method, the relative justification parameters are applied, by using a single-page model to evaluate all of the proper image couple, inputs and selection of the most probable solution, in order. As a result, a feature adaptation technique used to resolve the parameter is directly determined.
Mahdi Modiri
Volume 19, Issue 76 , February 2011, , Pages 2-9
Abstract
Digital orthophoto contains maps and geometric features of the map, and is accordingly able to: 1) As a source of spatial geography, be complemented by descriptive information. 2) Provide a base on which other data are recorded and adjusted. 3) The results of using it will be available to match landscapes. ...
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Digital orthophoto contains maps and geometric features of the map, and is accordingly able to: 1) As a source of spatial geography, be complemented by descriptive information. 2) Provide a base on which other data are recorded and adjusted. 3) The results of using it will be available to match landscapes. In many countries, digital orthophoto is an important part of the graphic documentation, and is used at strategic levels, which provides appropriate cartographic features on a national scale. Digital orthophoto has a strong potential for analyzing the geographic information system (GIS) data. Not only is orthophoto a layer of information, but the connection of orthophoto digital data presents a new perspective to automatic extraction of positional data (point, line, and surface) and altitude information. A large-scale orthophoto is prepared with a great deal of details, and makes the revision of many of information layers possible, and in some cases, plays a background role and is used to represent the position of elevation features. Therefore, large-scale satellite orthophoto has, in many cases, overcome the defects of orthophoto and, in accordance with the scale of study and urban planning, presents a valuable efficiency in detecting buildings hidden among complexes and high-rise buildings.
Mahdi Modiri
Volume 19, Issue 75 , November 2010, , Pages 2-8
Abstract
Continuous modeling and monitoring of urban environmental quality (urban environmental supervision) requires updated and continuous information regarding the heat distribution model, contamination, population, security, industry and crisis management. Remote sensing is a technology that uses a series ...
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Continuous modeling and monitoring of urban environmental quality (urban environmental supervision) requires updated and continuous information regarding the heat distribution model, contamination, population, security, industry and crisis management. Remote sensing is a technology that uses a series of distant measurements without any physical contact, providing useful and applicable information in accordance with various urban planning environments. The basis of remote sensing is to measure and record the physical and chemical properties of the atmosphere and the earth's surface from a remote distance, by special means called sensor, which is installed on different platforms. The sensors are divided into active and passive groups, depending on whether they themselves are the energy source or register energy reflection. LIDAR is one of the active technologies that provides special solutions for access to the information needed for urban studies and planning. LIDAR, in comparison with other remote sensors, whose source of energy is the sun and which practice imaging during the day, can collect urban data at different times of the night, and with this feature, provides access to the information required by the transportation planning, traffic, population estimates, employment, and environmental quality assessment.
Mahdi Modiri
Volume 19, Issue 74 , August 2010, , Pages 2-8
Abstract
The environmental quality of the city is a dynamic and multifaceted conception that addresses the possible natural and human factors in different spatial scales. Satellite information is the only suitable source of information in order to achieve the continuous dynamic characteristics of urban environments ...
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The environmental quality of the city is a dynamic and multifaceted conception that addresses the possible natural and human factors in different spatial scales. Satellite information is the only suitable source of information in order to achieve the continuous dynamic characteristics of urban environments in cities. However, until recently, satellite sensors were not able to record and display details of urban areas. Since urban information systems require high resolution data, aerial photography has been used as standard image input. In any case, the invention of new satellites with multi-spectral and high-resolution sensors (1 meter or less for Quick Bird, Ikonos satellites) and digital aerial scanners with excellent geometric characteristics and appropriate spatial resolution in scale of centimeters, has challenged the technology of analog aerial photography. High-resolution multispectral sensors and digital photographs, along with the location and coordinate data of the global positioning system and automatic navigation systems, create the conditions for updating the database of GIS. Another source of three-dimensional information for modeling is the sensors with laser scans that produce relatively accurate, high-quality altitude information. The paper focuses on the process of the development, the description of spectral combination techniques and the specifications of the images in order to properly assess the urban quality and environment.
Mahdi Modiri
Volume 19, Issue 73 , May 2010, , Pages 2-33
Abstract
Once the human being limited the breadth of the earth to his own area of vision, and wherever he had been born, he lived all his life there and maybe for hundreds of thousands of years his knowledge did not exceed that of the world around him. Apparently from the very first days, humanity, in order ...
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Once the human being limited the breadth of the earth to his own area of vision, and wherever he had been born, he lived all his life there and maybe for hundreds of thousands of years his knowledge did not exceed that of the world around him. Apparently from the very first days, humanity, in order to not forget, or to transfer information about the earth to his children, has probably made various lines and motifs on the walls of his cave or whatever type of residence. Thus, according to the historians, the germ of two important modern knowledge has been formed by the first human being, one obtaining information about the earth's surface, that is, geography, and the other the recording of information about the earth in the form of lines and images, in other words, a map which is cartographic, and these two human knowledge have become so closely connected from the very beginning that they are actually considered interdependent, and with such a firmness that the existence of one without the other is not imagined as possible. In the course of the evolution of automation, the real shift from mapping to creating spatial databases was a very attractive and valuable beginning, and provided an effective presence of cartography in all stages of study, planning, preparation of operational plans, implementation and evaluation. The main role of automation is in creating a spatial database, which is in response to a variety of needs of earth’s applied science and technology and of building structures. Creating a map is one of the dozens of possibilities provided by spatial database. The Internet is a very important tool that has played a major role in receiving and disseminating information over the past few years. The global communications network delivers and publishes the most recent news concerning geographic data. In this process, the map has an essential position and has a multi-purpose function. Maps can play their historical role in providing information for geographic plans and their conditions.
Mahdi Modiri
Volume 18, Issue 72 , February 2010, , Pages 2-10
Abstract
The environmental data of remote sensing is the basis of the preparation of maps and information with appropriate quality for the assessment of the change and evolution of the urban dynamic environment, which provides awareness of changes of details in relation to the characteristics of the studied area ...
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The environmental data of remote sensing is the basis of the preparation of maps and information with appropriate quality for the assessment of the change and evolution of the urban dynamic environment, which provides awareness of changes of details in relation to the characteristics of the studied area and effective parameters. The methods of combining the multiple parameters with other factors into one index have been studied, but due to the lack of criteria for precise evaluation, only general conclusions can be made. However, the large and significant correlation obtained from Combined GIS Method and Principal Component Analysis (PCA) indicate the compatibility between these two methods.
Mahdi Modiri
Volume 18, Issue 71 , November 2009, , Pages 1-80
Abstract
The design of arches in the production of accurate topographic maps such as road geometric design, short-range photogrammetry and medical simulations is based on arch type and in accordance with design goals. What is connected with establishing proper interconnection between design points is very important. ...
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The design of arches in the production of accurate topographic maps such as road geometric design, short-range photogrammetry and medical simulations is based on arch type and in accordance with design goals. What is connected with establishing proper interconnection between design points is very important. The algorithm of linkage between design points, if it is based on the shortest path, leads to a combination of broken lines and, if it is necessary that it have curvature upward or downward, and to what extent, are among the matters that have always been of particular interest to the cartograph engineers, and proportional to users expectation, the Spline, Fitcurve, and TIN methods have been recommended. Each technique has a share in alignment with the user's desire to simulate the surface features. This paper examines the advantages of marking based on nodal spacing for B-Spline curves and provides formulas based on nodal spacing for common B-Spline operations such as node’s degree and derivative. Using a node spacing-based marking, Spline introduces a multi-degree curve that is similar to the B-Spline type and consists of polynomials or with a number of degrees. MD-Splines are a generalization of the B-Spline curve, in the sense that if the curved sections in a MD-Spline have the same degree, MD-Spline will be reduced to a B-Spline curve. This section deals with MD-Splines of grades 1, 2, 3, and also degrees 1 and n. MD-Splines has local support, follows the body, the convex structure and the reduction property of the variation, and is at least of (Cn-1)th degree, in which n is smaller than the degrees of the two parts of the adjacent curve.
Mahdi Modiri
Volume 8, Issue 31 , November 2009, , Pages 2-5
Abstract
Considering the fast growth of population and the following urban development and expansion, the International Federation of Surveyors (FIG), during its permanent commission attended by a delegates of land management experts, has published a declaration concerning the importance of land management and ...
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Considering the fast growth of population and the following urban development and expansion, the International Federation of Surveyors (FIG), during its permanent commission attended by a delegates of land management experts, has published a declaration concerning the importance of land management and the role of surveying engineers in development of human habitation.The declaration has been prepared by collaboration of the UN’s Habitat, and can achieve its goals only if its recommendations are implemented; so it is asked from all countries to stay committed to fulfilment of the declaration’s requirements, and the international society is to use all its power to realize its goals.In the FIG congress in Helsinki, the head of the UN’s Habitat has declared:“Land is the starting point of all human habitation, and surveying engineers stand at the first stage of this process”.This statement shows the cosmopolitan responsibility of the surveyor. This paper describes the issues related to the content of this declaration.
Mahdi Modiri
Volume 8, Issue 31 , November 2009, , Pages 24-30
Abstract
The color of maps has a special importance in cartography. Legibility and clarity of a map and its agreement with reality (nature) is fulfilled with the help of colors. Application of various colors in map is carried out according to natural conditions and land features and the aim and scale of maps ...
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The color of maps has a special importance in cartography. Legibility and clarity of a map and its agreement with reality (nature) is fulfilled with the help of colors. Application of various colors in map is carried out according to natural conditions and land features and the aim and scale of maps based on principles of cartography. Selection of colors in maps should be from esthetic point of view and accompanied by artistic qualities that can help introduce the face of the earth better and add to the map’s delicacy.In the issue of maps’ color some basic considerations such as choice of color and the method of implementation of colored print should be taken into account so that color design of maps can increase the practical values of maps.
Mahdi Modiri
Volume 18, Issue 70 , August 2009, , Pages 2-8
Abstract
The old cadastral maps present the geographic form of the divided land and record relevant information about them. These maps were usually depicted on A4 or A3 size papers, and only show cadastral information, related to the blocks of small towns. In recent times, many countries in the world have, in ...
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The old cadastral maps present the geographic form of the divided land and record relevant information about them. These maps were usually depicted on A4 or A3 size papers, and only show cadastral information, related to the blocks of small towns. In recent times, many countries in the world have, in implementation of cadastral plans, produced new cadastral maps, and, based on multiple purposes, use the scale of 1: 1000, 1: 2000 and 1: 2500. Japan, for example, has set a new cadastral map scale of 1: 2,500. (iaoyong C, 1999) Rebuilding and editing old cadastre to be prepared for adding new cadastral plan requires generalization operation and editing process. Here, we present an algorithm for automatic generalization of old cadastral maps based on comparative drawing, and by mentioning a practical example, the efficiency of the algorithm is determined.
Mahdi Modiri
Volume 18, Issue 69 , May 2009, , Pages 2-12
Abstract
Map generalization, in accordance with different needs of users, is carried out using a multi-scale database. Such production is based on the analysis of map preparation requirements according to users’ needs, and indicates different requests and limitations of user’s desirable cartography.
In ...
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Map generalization, in accordance with different needs of users, is carried out using a multi-scale database. Such production is based on the analysis of map preparation requirements according to users’ needs, and indicates different requests and limitations of user’s desirable cartography.
In this paper, the process of generalization is expressed as a function of a non-generalized universal set to a generalized target set. Both these sets are defined by the ground-space qualities. The universal set keeps certain qualities including geometric, topological and non-space (like compound) qualities. These characteristics must be preserved by using generalization and so, the target set follows the qualities of universal set. Keeping these qualities unchanged causes that the generalization function preserve a state of consistency between the two collections with ground-space signs. Constant qualities are recorded and are found out as a result with consistent emphases. Consistent emphases bring about a state of consistency from a series of generalized information as a support for the structure of generalization function.