Mahdi Modiri
Volume 6, Issue 24 , February 1997, Pages 2-6
Abstract
Computer can be programmed in order to draw maps at different graphic levels with the help of various output systems including printers, plotters and display systems. These automatic graphic machines share one attitude: they carry out whole or part of drawing with reliable speed and accuracy several ...
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Computer can be programmed in order to draw maps at different graphic levels with the help of various output systems including printers, plotters and display systems. These automatic graphic machines share one attitude: they carry out whole or part of drawing with reliable speed and accuracy several times greater than human’s hand. On the whole, basic information of these maps, implemented by manual or automatic methods, must be fed into computers.
Majid Mokhtarani (Translator)
Volume 6, Issue 24 , February 1997, Pages 7-19
Abstract
Today, despite the emergence of precise surveying devices for ranging, including its more advanced type, namely GPS, the question still remains about the accuracy of such machines. Possibly accurate measurement is not necessary in many ordinary surveying works, but in fine works it is necessary that ...
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Today, despite the emergence of precise surveying devices for ranging, including its more advanced type, namely GPS, the question still remains about the accuracy of such machines. Possibly accurate measurement is not necessary in many ordinary surveying works, but in fine works it is necessary that the accuracy of spacer be controlled and determined. One of the most important surveying operations which needs great precision is microgeodesy. This operation has applications in measuring dams’ displacement, earth’s tectonic movements, landslides and even predicting earthquake and rise or fall of sea levels, installing an important piece in giant factories and measuring its movements, etc. In such operations, the spacer is used after determining its precision. Despite rapid advancement of GPS receivers in surveying operations, they are still not used singly in microgeodetic works, because their relative precision is not suitable for such operations, especially in short distances. Consequently it is used merely as a complementary. Electronic spacers have the highest precision in short and long distances. If we take a look at the precision of spacers in various distances, we notice that up to five kilometers the electronic spacers, especially those working based on two-color method are of high accuracy. From eight to thirty kilometers the single-frequency GPS systems, from thirty to eighty up to a hundred kilometers the two-frequency GPS systems, and in higher distances ranging by the SLR and V.L.B.I methods are of great precision.
Mohammad Mosayyebi
Volume 6, Issue 24 , February 1997, Pages 20-23
Abstract
Based on the reports published in global health magazines, about one-fourth of people of the world are deprived of suitable shelter, and a hundred million people have no house and lie in streets, under bridges and in other improper places. Therefore, housing is a global problem, and it is certain that ...
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Based on the reports published in global health magazines, about one-fourth of people of the world are deprived of suitable shelter, and a hundred million people have no house and lie in streets, under bridges and in other improper places. Therefore, housing is a global problem, and it is certain that traditional patterns and methods can by no means respond acceptably to these increasing need. Furthermore, other factors such as environmental considerations, lack of enough investment and skilled force and natural problems are among the limitations of housing plans and management.
It is obvious that creation and establishment of efficient and modern architecture and urban texture in agreement with the culture of time and place must be based on leaving classic characteristics and removing the single-story attitude. Moreover, for achieving agreement between housing and urban texture from artistic and social order point of view, we must consider environmental, artistic and social order balance together when analyzing the relationship between human and housing.
Attention to historical characteristics of each nation is a necessity in housing plans that is very effective in the success and comprehensiveness of these plans.
Considering that in large cities the problems of transportation, air pollution, shortage of space, excessive occupation of urban lands by highways, inefficiency in movements within the city and countless environmental problems are due to lack of a comprehensive plan in design of residential spaces, so due care in management and housing plans is the first step for avoiding such problems.
In this paper, while considering the environmental problems of cities, the main sources of environment, namely matter, energy, space, time and variety have been taken into account, and it has been emphasized that it is necessary to define quantitatively a comprehensive plan containing all factors that affect housing plans, and to implement it into geographic information systems. Then, using GIS software and computer modeling, the layers or combinations of such plans should be assessed and, considering their advantages and disadvantages, the best approach for housing plans shall be proposed according to national culture and environmental conditions.
Hamid Bahiraei
Volume 6, Issue 24 , February 1997, Pages 24-27
Abstract
In order to carry out marine military maneuvers, it is of great importance to have detailed information about what lies on sea’s bed or even lower. Today there is a kind of competition over establishing a type of connection by which the information can be transmitted between ships and the shore ...
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In order to carry out marine military maneuvers, it is of great importance to have detailed information about what lies on sea’s bed or even lower. Today there is a kind of competition over establishing a type of connection by which the information can be transmitted between ships and the shore or between ships themselves in real time (immediately). Experiments conducted on Italian shores using GIS navigational charts proved that utilization of GIS has been very successful.
Abbas Khosravi
Volume 6, Issue 24 , February 1997, Pages 28-33
Abstract
Mangrove is a tree with natural form, ornamental fruits, beautiful leaves, well-shaped branches and pleasant blossoms which has grown under special conditions in sea water in the Qeshm Island. The crest of these trees rarely appears during water’s high tide, and their lower parts which usually ...
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Mangrove is a tree with natural form, ornamental fruits, beautiful leaves, well-shaped branches and pleasant blossoms which has grown under special conditions in sea water in the Qeshm Island. The crest of these trees rarely appears during water’s high tide, and their lower parts which usually contain respiratory roots can be witnessed only during low tides. The beautiful appearance of these trees is such that they charm any viewer, especially those who visit Qeshm for the first time.
The Mangrove Trees, the cause of the special beauty of sandy shores of the northwest and west of the Qeshm Island, are studied in this paper.
Fatemeh Razi'ee (Translator)
Volume 6, Issue 24 , February 1997, Pages 34-38
Abstract
Energy is released at the center of the Sun. This energy moves toward the surface of the Sun, and is spread in space as light and heat. The surface of the Sun is called Photosphere. There are dark spots on the Sun which are called Sunspots. There are thin gaseous layers above this celestial body which ...
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Energy is released at the center of the Sun. This energy moves toward the surface of the Sun, and is spread in space as light and heat. The surface of the Sun is called Photosphere. There are dark spots on the Sun which are called Sunspots. There are thin gaseous layers above this celestial body which are called Chromosphere or the Sun’s gas rings, and which leave the Sun’s surface into the space. There is an aura of gas around the Sun called corona which can be seen only at poles. Atomic particles are emitted from the Sun like a current and reach planets including Earth. These currents are called solar winds.
Nasrallah Mowlaei Hashjin
Volume 6, Issue 24 , February 1997, Pages 39-46
Abstract
Our country, due to its special geographic position, especially the location of its north and northeastern borders which have been gates for entrance of nomadic tribes, has been affected by the phenomenon of nomadism since early times. Consequently, it is considered as one of the most important areas ...
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Our country, due to its special geographic position, especially the location of its north and northeastern borders which have been gates for entrance of nomadic tribes, has been affected by the phenomenon of nomadism since early times. Consequently, it is considered as one of the most important areas of nomadism in the world. In general, Iran has a history of nomadism of about eight thousand years, a fact confirmed by relics found in the northwest of Iran.
Therefore, Iran is a land familiar with nomadism in which nomads, despite their decreasing trend of population, have been recognized as the third population group of society along with rural and urban settlers since long ago.
Unfortunately, this small and scattered population faces problems concerning its three fundamental bases, namely human, livestock and rangelands all over the country.
In this paper, using theories, experiences and statistical information, it has been tried to examine the necessity of transforming the manner of nomadism in Iran into transhumance in order to help nomads enjoy existing infrastructures and facilities, an aim in line with the policy of homogeneous economic, social and cultural development of the country.
In this regard, first a brief overview of nomadic life characteristics and difficulties has been presented, and then transhumance and its role in different aspects of the life of nomads have been studied.
Hamid Malmirian (Translator)
Volume 6, Issue 24 , February 1997, Pages 47-52
Abstract
The progress made over the past three decades in cartography, remote sensing and geographic information systems is due to the necessity of establishing new connections among currently specified technical regulations. Great efforts have been made to realize desirable collection of various cartographic ...
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The progress made over the past three decades in cartography, remote sensing and geographic information systems is due to the necessity of establishing new connections among currently specified technical regulations. Great efforts have been made to realize desirable collection of various cartographic data and more successful utilization of remote sensing data of regional and international data banks.
The importance of remote sensing as an environmental information sub-system has significantly increased by launch of a number of new satellites equipped with electronic sensors and images able to present data and pictures from physical and human elements of earth’s atmosphere.
Cartographic display of spatial and temporal changes of the earth’s elements is the most important goal of thematic cartography. This goal has been confirmed by many cases of planning for map preparation on global, regional and local scales. Thematic map production has been recognized by many associations as a vital task in exploration of underground resources and environmental management and planning. The rapid progress of satellite systems has led to expansion of remote sensing and its applications in cartographic and map-completion activities.
The connection between cartography, remote sensing and geographic information systems can be indicated in various ways. It seems that the Fig.1-1 reflects the connection among the three systems without presence of special governing regulations.
Mahdi Nourbakhsh
Volume 6, Issue 24 , February 1997, Pages 53-56
Abstract
Evaporation is change of liquid water into vapor. In hydrological cycle, evaporation is a complex phenomenon whose estimation requires great deal of calculations. In this study, it has been tried to present a simple method for calculating potential evaporation, and to calculate evaporation from water ...
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Evaporation is change of liquid water into vapor. In hydrological cycle, evaporation is a complex phenomenon whose estimation requires great deal of calculations. In this study, it has been tried to present a simple method for calculating potential evaporation, and to calculate evaporation from water surfaces using statistical methods and climatic factors effective in evaporation. In this method, multi-variable regression and linear equation have been utilized. Statistical data of evaporation from tank has been used as function’s variable and factors of temperature and saturation deficit have been taken as independent variables. Finally, numerical values required by equation of line have been calculated using three-variable (three-unknown) equation; thus, the amount of potential evaporation from water surfaces is calculable if temperature and saturation deficit are known. The results from this method are in good agreement with the measured amounts of evaporation from the tank.
Masoud Abedi Pashtiri (Translator)
Volume 6, Issue 24 , February 1997, Pages 57-64
Abstract
Digital photo is the basis of digital photogrammetry. Digital photos make automatic measurement possible. One of the tasks in aerial triangulation is the measurement of photos. Organization of the process of measurements is effective in efficiency of aerial triangulation. One of the advantages of digital ...
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Digital photo is the basis of digital photogrammetry. Digital photos make automatic measurement possible. One of the tasks in aerial triangulation is the measurement of photos. Organization of the process of measurements is effective in efficiency of aerial triangulation. One of the advantages of digital photogrammetry is the step-by-step implementation of stages of work using computers. The main feature of automatic aerial triangulation lies in automatic measurement methods. A number of concepts related to this new technique are studied in this paper.
