نشریه اطلاعات جغرافیایی (سپهر)
پیاپی 49 (بهار 1383)

Geomatic Engineering and sciences include activities that involve obtaining (receiving, collecting, deducing and utilizing), processing (networking, scaling, computing, topological structure and simulation), analysis, display (topography, two-dimensional, three dimensional and animation display) and spatial information management (modeling and exploitation). Geosciences are not limited to geodesy, photogrammetry, mapping, cartography, geographic information systems (GIS) and cadastre, but include a wide range of environmental and spatial sciences with a variety of career opportunities. The widespread applications of engineering and geomatic sciences demand widespread theoretical and applied research. Geomatic specialists utilize information collection techniques (such as digital imaging and satellite positioning) and advanced computer systems. They play a major role in providing visualization and effective assistance in decision making, and in implementation and control of all construction over, under and above the ground in the following projects. • Design, construction and management of urban engineering projects • Obtaining (collecting and utilizing) information and production of maps and digital charts • Asset management such as land, transport infrastructure and property (by GIS, LIS) • Control of environmental changes and natural resource management (through remote sensing) • Urban planning • Earthquake prediction (through measurements of very slow motion of the Earth), • Control of the safety of various structures, such as stairs, dams, large buildings and towers. • Exploration and engineering for production of gas and oil in different areas • Measuring and controlling sensitive areas

Wetlands are significant not only materially, but ecologically as well. Hence the recognition of these natural ecosystems and efforts to protect them must be placed at the forefront of scientific and practical attention. In this regard, recognition of some of the ecological features of Hoor Shadegan as one of the vital zones will be sought. Hoor Shadagan is ranked as the twenty-second wetland in the world, and has various ecological, scientific, aesthetic, economic and hydrological values. The Shadegan wetland has been declared by the Environmental Protection Agency as a wildlife refuge due to the migration of various birds from northern areas of the globe to this place during the winter and early spring. This wetland was registered on 23 June 1975 by the Ramsar Convention as an internationally important wetland (especially for aquatic birds). (Majnounian 1998) The Shadegan wetland is located in a warm and dry climate, and in some years it is encountered in warm seasons with water shortage or aridity over a large part of it. The animals have adapted themselves to these ecological conditions over the years. (Farrokhian et al., 1997)

More than 25 years have passed from the date of development and implementation of the spatial method called “the base-lengths measurement using the Very Long Baseline Interferometry (VLBI)”. This method allows measurement of the motion of the Earth's Crust in an unusual way. The VLBI provides a unique ability to determine the format of inertial basis and to measure ground justification. Changes in ground justification in the inertial space are due to the following two issues: A. The gravity force of the Moon and the Sun B- The reaction of the sum of angular movements between the Earth's Crust, the oceans, and the atmosphere. The VLBI provides a direct measurement of ground justification in space, by which the Earth scientists examine cases including phenomena such as atmospheric angular torques, tidal currents of the oceans and reflections of solid (rigid) ground.

The province of West Azerbaijan, due to its geographical location, topographic conditions and governing atmospheric systems, experiences from cold to semi-cold weather over the main part of the year. Consequently, during five to eight months of the year, cold-to-cool bioclimatic conditions prevail in the province. Owing to these conditions, the main priority in the overall design of buildings is that of receiving the maximum radiation energy in residential areas, especially in the cold season. Considering the prevalence of cold and cool bioclimatic conditions in the province as well as the little need for the air flow to create comfortable conditions in the environment (less than 10% in year), the best direction for using solar energy to heat residential areas is “southeastern” in the southern and central parts of the province, and “southern” in the northen part of the province.

Today, most of the water found on the surface of the earth is in lakes and oceans in the form of liquid. Almost two percent of water is in the form of solid as ice at high altitudes and geographic latitudes. About ten percent of the earth’s surface is covered by glaciers. Over a million years or more, the glaciers have consistently been on over 30% of the earth's surface. The main era took place during periods when the earth’s climate was colder than its current state. The formation of glaciers occurred both in the form of formation of a "glacier in the valley” in which ice occupied the mountainous valleys, and in the form of continental glaciers in which large parts of several continents were covered with ice with a thickness of three kilometers. This arouses humans into thought and helps them describe the advancing ability of a glacier to cut land features along its course. We rationally discuss the formation of sedimentary lands due to formation of continental glaciers. Four distinct stages have been identified in the United States. The last ice age has been during the formation of the Wisconsin Glaciation, which occurred within a time interval between 70,000 and almost 10,000 years ago.
 

The history of the city of Karbala in Islamic Era begins since the martyrdom of Imam Hussein. Image (1) shows the space image of IKONOS, taken on January 3, 2003, from the shrine of Imam Hussein, along with the shrine of Abolfazl al Abbas and the spaces surrounding these two sites that form the central core of the city.
 
 

In this paper, we study routing in urban transport networks. Although urban transport networks are among dynamic networks, but using solutions that are available for static networks, the degree of complexity of these networks can be reduced. There are various algorithms for network analysis that we can use in this regard. Amongst these algorithms, Dijkstra is the most popular one, which has several types, including algorithms A and B. The most important problem with the analysis of urban transport networks is the problem of entering traffic information into the algorithm’s analyzer program because traffic information is constantly changing. Different parameters are effective in traffic, and we can not provide a reliable and effective model for urban transport networks due to the unpredictable nature of many of these parameters. In this paper, using the Java programming language in the Internet, a novel and innovative solution is presented to find the best route in urban transport networks.

The use of Geographic Information System (GIS) has broadly established its prominence among other sciences and is now used as a tool accepted by all existing systems and structures for work at the Earth’s level, and in particular the human population residing on it. GIS will also have vast applications as a coherent technology, a combined system (structure) reducing the disagreements among them; in fact, as essential prerequisites for creating necessary research infrastructures in each case. The author of this text introduces the GIS as a potential force for using broader chains of social sciences, as well as for social science research and related issues. In this paper, he examines and evaluates the strengths and weaknesses of technology, and in this regard, he puts forward six key concepts on how to use this system (GIS) in social sciences. He concludes his discussion with concepts related to the ground’s digital tools and connections and their potential values as a driving force.

With increasing development of GIS, the analysis functions applicable by it have also been significantly expanded, including network analysis. Finding the shortest path is among the important network analyses that is considered as one of the important applications in transportation issues. Considering the many applications of routing analysis, the variation in the type and volume of input information and various parameters affecting the efficiency of a routing algorithm in a geographic information system, various solutions have been proposed to solve the routing problem, including the Dijkstra and Genetic Algorithms. Dijkstra's algorithm is one of the most famous methods for finding the shortest route that can be used to find the shortest path in a given network using matrix computations. However, in instant applications, due to large volume of input information, complex constraints and the need for fast performance, this algorithm will lose its effectiveness. As computational volume increases in the network matrix, its time complexity increases as well. Genetic algorithm can be used to solve this problem. Genetic algorithm is an optimization technique that can reduce the amount of computations and number of comparisons by minimizing the search range. In this paper, with a brief overview of the Theory of Graphs, the operation of Dijkstra and genetics routing algorithms are reviewed and results of several practical works are presented. Finally, by comparing and verifying the results, the strengths and weaknesses of each of them will be determined.