نشریه اطلاعات جغرافیایی (سپهر)
پیاپی 66 (تابستان 1387)

The evolution and progress of the automatically vectorizing system is very important as a process input method that takes great time and cost. Most systems that vectorize roster data will force users to set different parameters for a particular map image. But it is difficult for novices to be able to modify the parameters properly and appropriately.
This paper explains a science-based system in order to achieve the automatic vectorization of roster information. This automatic system makes the right choice of parameters possible. Since the act of limiting input image data to produce a framework of proper length and width is a necessary condition for the automatic vectorization of roster data in several steps, so the implementation of limiting algorithms for sample data is systematically evaluated in the images of multiple map, and appropriate rules for maps are thus formed.

Tsunami is a natural phenomenon that can not be prevented from occurring and is considered as one of the most important oceanic disasters in the world. In this collection, along with providing a definition of it, the types and causes of its occurrence are presented and, according to its geographical distribution in the oceans and places affected by the subduction, some special sites are introduced and, according to its destructive results, it has been attempted, through making suggestions, to take measurements for places that are located along the coastline of the subduction by the way of presenting information about its effects, in order to anticipate the potential risks and possible damages. Considering that in the southern part of Iran, there is the coastline subduction of the Oman Sea and the tectonic of the Indian Ocean, there are potentials for such an incident.

In this article, we will look at the new American warfare policies that daily affect the world people’s plans for their lives. Dick Cheney, the current Vice President of the United States, who leads the White House’s war-mongering policies, has introduced a new hegemony called "the soft law". Meanwhile, human societies do not feel good about this term today. It is more tangible when it can be seen that bright human attractions are buried in the dark underground trenches and are referred to in fake terms such as "soft norms". Of course, most studies and commentaries on the September 11 terrorist attacks focus on how this event happened and how everything changed at once. From another point of view, after the occurrence of this event, a new era of historical relations and rules was born, especially in post-modern geopolitics, as the event was unfortunately recorded in human history in a precise date and in an exact hour that was a landmark and very meaningful in terms of its time of occurrence .

Undoubtedly, the flood is known as a natural disaster, but in practice, the flood is one of the most terrible natural disasters in the world in both terms of mortality and financial losses. Between 1988 and 1997, around 390,000 people were killed in natural disasters around the world, 58% of whom were related to flood, 26% were affected by earthquake, and 16% victims of hurricanes and other disasters. Total damage over the past 10 years was about $ 700 billion, of which 33, 29, and 28 per cent were related to flood, storm and earthquakes, respectively. In this regard, a worrying issue has been the increasing trend of mortality and flood damage in the world in recent decades. The phenomenon of flood in Iran is considered as the most harmful natural disaster whose damages account for more than 70% of the whole natural disasters. Increasing population and assets in floodplains, hydrosystem changes and destructive effects of human activities have been among the main reasons for this trend. Today, with the development of information technology, much emphasis has been put on the use of GIS to model and assess the dangers and damage caused by floods. The high speed and precision of these systems, their vast coverage and multi-aspect nature, and their ease of use and low cost have made them more and more utilized in managing the flood crisis. In this paper, we tried to use the GIS technique in managing the flood risk crisis in Kashan area.

Gully erosion is one of the types of ever-intensified water erosion whose occurrence and spread makes noticeable changes in terms of land degradation and environmental destruction. Considering the diversity and extent of the effect of various factors on the formation and expansion of gully erosion, which change from one point to another in terms of type and extent of effects, and in order to identify the most important factors contributing to the development of gully erosion on the lands, in this research, IRS satellite imagery of India, field inspection and vast field operations through GPS were used and the map of gully erosion distribution was prepared In order to identify, by aerial photographs to a scale of 1:20,000, the ways of preventing and controlling this type of erosion in the basin of Rahjerd, which is a watershed located in the province of Qom. Studies showed that lithology characteristics, slope, resources and land suitability, direction of slope and land use are the main factors affecting the occurrence of gully erosion. The results of this study showed that the lithological units of 25.88 per cent Mpa.bvt and 74.12 per cent QFt2 and the land type of fan debris flow in the form of gravel (alluvial fan) have affected 100% of the areas struck by gully erosion. In addition, the slope of 0-10% (93.6%), eastward slope (63.09%), and medium range pastures use (100%) have the most expanses of areas affected by gully erosion in the studied basin area.

There have been many ways of collecting data from a long time ago. Astronomical observation of land surveying, hydrography, photogrammetry and remote sensing are the main methods of location-based collection of information. Radar remote sensing is an interesting and special issue that reveals different aspects of remote sensing. Radar sensors called active sensors can capture images in almost all conditions, and obstacles like rainfall, cloud and night can not cause them any trouble. The term radar, which is used today throughout the world, has become an international term like radio and television. In fact, radar invention has been taken from a very natural physical phenomenon called reflection. Radio and electromagnetic waves are also capable of reflection, and the radar is based on this simple property. The simplest radars were actually formed by a transmitter and a radio receiver. Radar is an electromagnetic system that is used to detect and determine the target’s position. With the help of the radar the inside parts of environments like darkness, rain, snow mist, dust, and … that are impenetrable to the eye become visible. However, the most important advantage of the radar is its ability to determine the distance from the target’s range. The application of radars is for ground, air, marine, spatial and meteorological targets. Fabricating a high-capacity system for tracing phenomena and creating high-quality images of them is the main goal of the construction of imaging radar. In this article, we have tried to introduce active sensors in general to emphasize on radar systems and the mechanism of their operation, and to introduce the features of these images and provide a ground for more applied research in the future.

Considering that the district 22 is located in the corridor of the air flow from west to east of Tehran, its pollutants are very little in comparison with other areas. Therefore, in order to measure the pollutant in air pollution studies, 9 stations were selected in different locations, each with special characteristics. Due to the diversity of neighborhoods in the district and the impact of various factors, these stations will indicate air pollutants in relevant locations.

In this paper, while introducing a brief overview of Chaharmahal and Bakhtiari province, the most important zoning method (Terjung) has been discussed using parameters of temperature, relative humidity, sunny and windy hours in 8 synoptic and climatological stations during a statistical period of 40 years. Next, bioclimatic zoning maps were prepared on a seasonal scale.
In order to achieve these maps the Terjung method, statistical-graphical software, elevation gradient, and especially the buffering of AutoCAD map and ArcView were used. Data analysis during this period revealed the ecological groups of Chaharmahal and Bakhtiari province. In winter, due to the dominance of external climatic factors, only one bioclimatic region (K2) is discernible throughout the province; in the spring, the combined effect of external and local factors create three bioclimatic types (W2, M3, C2) and in the summer season the effect of local factors create two bioclimatic types (W4, H5). By change in the effective factors in the autumn, the bioclimatic types (C2, C3, K2) are dominant in the Chahar Mahal and Bakhtiari province during this season.

Since the processing of location information in the form of a map makes its understanding quick and easy and is an effective factor in the analysis of spatial issues, crime mapping has during the last decades been of interest to various law enforcement and judicial organizations as well as relevant scientific and research institutions in different countries of the world, especially advanced countries in the western world. The present paper seeks to clarify this issue by examining two common ways in this regard. The first method of crime mapping is through the GIS computer software, and the second method is the location - or land-based - naming of information obtained from various sources and their retrieval through map referral. It also emphasizes how the above-mentioned methods can, during their evolution, help police and related organizations, especially detectives and criminologists, in the future.

Avian Influenza is one of the fatal diseases among wild and domestic birds, causing major damage to the agricultural economy both naturally and artificially (slaughtered by humans). Despite the fact that it has caused a lot of damage to protein producers in different parts of the world, its emergence, spread, manner of dealing with it and fighting it, and people's awareness about this disease are still far from clear, So that they are now left in an uncertain situation. The present study was conducted using available secondary and Internet sources and documents with the aim of identifying the pathway of the geographical spread of the disease and its rate in the period from January 2006 to July 2006. The results of the study indicate that the prevalence of this disease was from the southeastern Asia and its movement to Europe, Asia and Africa, and seven months after the discovery of this disease, 53 countries have declared detecting cases of the disease during the mentioned period.

The purpose of this paper is to investigate the historical evolution of Babolsar in the geographical context of its neighborhoods, which has led to the formation of Babolsar's current neighborhoods. In this paper, the author has tried to study Babolsar in 5 crucial stages of its evolution, and to draw a parallel between its past neighborhoods and the current ones. Most of the discussion is based on the geographic location of the old neighborhoods and imagination of Babolsar's past based on its current state.