Ali Akbar Rasuli; Ali Mohammad Khorshiddoust; Mojtaba Fakhari Vahed
Abstract
Extended Abstract Introduction Lightning is one of the most fascinating climatic phenomena, which has not yet been fully understood. This phenomenon usually occurs during thunderstorms and at the times of electrical field failure in a variety of cloud-to-ground, cloud-to-cloud, and in-cloud or intra-cloud. ...
Read More
Extended Abstract Introduction Lightning is one of the most fascinating climatic phenomena, which has not yet been fully understood. This phenomenon usually occurs during thunderstorms and at the times of electrical field failure in a variety of cloud-to-ground, cloud-to-cloud, and in-cloud or intra-cloud. The cloud-to-ground lightning which strikes the ground is one of the most important causes of mortality due to weather conditions. Lightning can also cause many financial losses such as damaging power lines and causing fire. Therefore, spatial distribution of lightning is essential in terms of energy and safety management. Furthermore, our community, which increasingly relies on information networks, helps to identify the areas prone to lightning in order to protect the information systems. Lightning activities vary widely on the spatial and temporal scales, and depend on local convectional activities to some extent. The knowledge of lightening activities was usually based on surface measurements over time, prior to the arrival of the satellites. But, the activity of these storms is not measured in places where there are no synoptic stations. Therefore, it is necessary to predict the exact location and the severity of convective storms based on the development and monitoring of the route for timely notification. This is because all measurements related to thunderstorms in Iran are recorded with a three hour interval in various codes and only at synoptic stations. Materials and Methods This study was carried out using lightning data recorded in space by LIS sensor in a period from January 1998 to December 2013 (16 years). Lightning imaging sensor (LIS) is installed on the TRMM satellite. The LIS sensor is an optical detector that measures light-induced and light-intensity variations in clouds in the range of 777 nm/s and is capable of observing thunderstorms with a scale of 3 to 6 km on a 600x600-km while the effective LIS efficiency is 90% at night and 70% at local noon time. At the first stage of data analysis, it should be determined that the data are randomly distributed or have a certain spatial trend. Some of geographic processing functions were applied to data in the GIS software to compute the statistical values and to determine the locations having significant lightning levels. These calculations are done based on the Euclidean distance between the points (thunder and lightning) and the spatial concept of that weighting method based on the inverse distance. Other indices also compute the spatial distribution of the data. The nearest neighbor index (NNI) and the Kernel density function are among these indices. The NNI is expressed as a proportion of the observed distance to the expected distance, assuming the random distribution of the images. To generalize the geographic location of a phenomenon (lightning occurrence) to the whole area, the Kernel density interpolation estimator has been used throughout the region. In fact, the Kernel density function in the GIS software calculates the density of the features in their neighborhood and can be used for linear and point features (lightning). Results and Discussion The results of this research showed that the maximum frequency of lightning occurs in the southeast of Iran in the months of March to August (warm period of the year). Its highest frequency is in August and its lowest frequency is in December. In the study of daily changes it was also found that from the early afternoon until late afternoon (from 1300 to 1600 hours local time), the lightning activities significantly increase, which seems to be related to local convectional activities which are along with the surface heat created by daily radiation of the sun. The nearest neighbor index results showed that the data distribution follows the cluster pattern. In other words, some regions have more favorable conditions for lightning. The results of the Kernel density index indicated that these areas are in the southern slopes of the region and its maximum is located before the main peak. The maximum frequency of lightning lies between 26° and 27° N, and is on the same orbital direction. Given the maximum lightning occurrence time which is during the warm period of the year, it seems that the southern currents created by the monsoons of the Southeast Asia along with local topography, is the exacerbating factor for the lightning activities in the southeast of Iran, and in particular, the region with a maximum lightning activities. Conclusion The use of satellite data to illustrate the distribution of some climatic phenomena can be very useful, since the frequency of some phenomena (especially lightning) is not recorded on ground stations. On the other hand, the distribution and density of ground stations are not appropriate, because the density of synoptic stations is particularly in low mountainous regions and the shape of the land in these areas is complex, and the distribution of thunderstorms is affected by this form of land. As it was observed in the results, one of the most important factors of the frequency distribution of lightning is the roughness, and these results indicate that remote sensing technology can be used to calculate the distribution of the phenomena of interest with high precision.
Mas'ud Torabi Azaad; Rahim Eftekhari; Aliakbar Rasuli; Amir Siyah Sarani
Volume 17, Issue 67 , October 2008, , Pages 57-61
Abstract
During the 2001 World Ocean research patrol in the Caspian Sea, physical parameters of temperature, salinity and density of the Caspian Sea were measured. The range of selected stations for measuring these parameters included the entire Caspian Sea. Of course, these measurements have been taken discretely ...
Read More
During the 2001 World Ocean research patrol in the Caspian Sea, physical parameters of temperature, salinity and density of the Caspian Sea were measured. The range of selected stations for measuring these parameters included the entire Caspian Sea. Of course, these measurements have been taken discretely in the studied area. In the present study, the spatial modeling of these parameters have been carried out using the ArcGIS 9.2 software, and the current state of the work is the creation of continuous maps of the parameters present at various depths with high validity. These smart maps have the ability to to provide with the parameter value of each place of particular coordinates in the studied area with a mouse pointer click.
Ali Akbar Rasuli; Mas'ud Minaei
Volume 17, Issue 65 , May 2008, , Pages 60-64
Abstract
This paper presents an introduction of air pollution’s situation assessment in an urban area. The author uses the GIS, which combines the vehicle distribution model, pollutant release model, progress model and related data, in order to estimate the propagation and spatial distribution of traffic ...
Read More
This paper presents an introduction of air pollution’s situation assessment in an urban area. The author uses the GIS, which combines the vehicle distribution model, pollutant release model, progress model and related data, in order to estimate the propagation and spatial distribution of traffic pollutants in the city of Taichung in Taiwan. This model can not only analyze the exact location of pollution, it can also predict emissions affected by changes in specific traffic conditions or strategic management. The results show that more CO emissions occur around areas located in the center or south of the city in Taichung, and the range of highway 1 suffer SOx, Nox and TSP pollutions more than rest of the city. Although the part of highway 1 within Taichung is not very long, it nevertheless plays a role in production of a significant portion of total suspended particulate (TSP), nitrogen oxides (NOx) and sulfur oxides (SOx) in this area. Moreover, the prediction of several hypothetical designs suggests that the main effect of advanced engines on reducing TSP emissions is more than 10%, while the average speed increase of urban road traffic may reduce CO by more than 14%.
Ali Akbar Rasuli; Mas'ud Mina'ii; Mahmud Davoodi
Volume 16, Issue 61 , May 2007, , Pages 43-46
Abstract
The application of remote sensing data is illustrated by the example of the Mount Damavand (5671 m) in the Alborz mountain range in Iran. Several types of satellite data were needed to carry out the complex monographic work on the mountain range: SSEOP images from NASA, Russian KFA-1000 images, CORONA ...
Read More
The application of remote sensing data is illustrated by the example of the Mount Damavand (5671 m) in the Alborz mountain range in Iran. Several types of satellite data were needed to carry out the complex monographic work on the mountain range: SSEOP images from NASA, Russian KFA-1000 images, CORONA panoramic images from NASA and Russian KVR-1000 orthoimages. There are examples of studies of climate, transportation routes, water resources, protected areas, and relics of human land-use that demonstrate the potential of remote sensing data. Correct selection of image data in using remote sensing is a necessity for documenting and monitoring human activities.
Majid Zahedi; Ali Akbar Rasuli; Abdollah Faraji
Volume 13, Issue 52 , February 2004, , Pages 24-29
Abstract
Water is one of the main factors of natural environment which has a great influence on other environmental factors and human activities. Climate elements have direct and indirect impact on human life. The climate type of each region represents vegetation, soil, animal life, water status, and, to a large ...
Read More
Water is one of the main factors of natural environment which has a great influence on other environmental factors and human activities. Climate elements have direct and indirect impact on human life. The climate type of each region represents vegetation, soil, animal life, water status, and, to a large extent, human economic activities including industrial, agricultural, tourism, etc. are controlled by the elements of the climate (Hobbs 1981) Climatic elements and parameters have applications in most of regional construction plans. Without attention to climatic elements and their exact study, most regional planning will certainly face difficulties. One of the best methods for recognizing the climatic elements of a region is having a comprehensive and basic information about these elements and their zoning. The zoning of climatic elements such as radiation, temperature, precipitation, humidity, pressure, etc. and preparation of their zoning maps can be used as a tool for planners. Today, Geographic Information System (GIS) technology is instrumental in geography. Accurate and advanced software of GIS (such as Arc / info, Arc / view, Arc /... GIS) and modern hardware (fast computers, scanners, plotters, printers, etc.), have, in addition to facilitating the work of geographers in the study and analysis of various scientific issues, increased the accuracy and speed of their operation. Currently, most branches of the science of geography utilize the GIS in urban, rural, regional, land lay, hydrologic, meteorological, environmental, etc. analyses and studies. The large region of Azerbaijan (East Azerbaijan, West Azerbaijan and Ardebil) in the northwest of the country is one of the regions of the country with climatic diversity. Due to different topographical conditions and passage of western air masses, special climatic conditions have dominated the region. In this study, the elements of the Azerbaijan climate were analyzed and zoned using Arc / View software. Finally, the climatic zoning maps of the area were drawn up for each of the parameters.
Ali Akbar Rasuli
Volume 9, Issue 33 , May 2000, , Pages 15-18
Abstract
In recent decades geographic information systems, as a dynamic and unique industry with the aim of optimal management of spatial data, have been accessible to geoscience researchers. This multi-purpose technology has been defined as a set of computer hardware and software used by experts for reception, ...
Read More
In recent decades geographic information systems, as a dynamic and unique industry with the aim of optimal management of spatial data, have been accessible to geoscience researchers. This multi-purpose technology has been defined as a set of computer hardware and software used by experts for reception, storage, process, analysis and display of various types of land information. Based on this definition, it can be inferred that the role of skilled human force in running, control and utilization of an efficient, specialized and somehow complex set of computers is of great importance. Therefore, the main role of this paper is to analyze the duties of experts who play a role in the dynamism of this industry through organized collaborations and team-work.
Ali Akbar Rasuli
Volume 8, Issue 29 , May 1999, , Pages 6-13
Abstract
Geographic information system (GIS) is a phrase for expressing a deep, broad concept. Basically, geographic information system is a computer technology including hardware and software which has emerged in recent decades with the aim of reception, organization, analysis and finally design and production ...
Read More
Geographic information system (GIS) is a phrase for expressing a deep, broad concept. Basically, geographic information system is a computer technology including hardware and software which has emerged in recent decades with the aim of reception, organization, analysis and finally design and production of various models (such as maps of underground resources) and which is currently evolving toward completion. The determining factor which distinguishes this technology from other systems of information storage and recovery is its attitude toward geographic places. This quality has helped GIS as a new technology to turn into a dynamic industry in analysis of quantitative and qualitative data and design of various types of geographic images.
In this paper, it is tried to briefly consider space imaging using GIS and to introduce the principles of geographic image design.
Aliakbar Rasuli
Volume 2, Issue 7 , August 1993, , Pages 42-51
Abstract
The main purpose of GIS is to prepare and direct special spatial information. In Clarke's view, the GIS mechanism includes software tools that use computer hardware to feed, store, modify, interfere, change, analyze, and finally display geographical data. Furthermore, according to an authority in the ...
Read More
The main purpose of GIS is to prepare and direct special spatial information. In Clarke's view, the GIS mechanism includes software tools that use computer hardware to feed, store, modify, interfere, change, analyze, and finally display geographical data. Furthermore, according to an authority in the field, the GIS process refers to a set of information series and modeling methods that present final results through computer. Therefore, this system, as an internal automated reference, is able to use the provided special information and analyze the results or present them in the form of maps.
Aliakbar Rasouli
Volume 1, Issue 4 , May 1992, , Pages 9-11
Abstract
In 1988, Ahnert presented a special type of land form classification, with which a connection has been established between the approximate age of forms of land with their morphological size. During operations with large geomorphologic maps of scale 1: 25000, the following studies are necessary:
1- ...
Read More
In 1988, Ahnert presented a special type of land form classification, with which a connection has been established between the approximate age of forms of land with their morphological size. During operations with large geomorphologic maps of scale 1: 25000, the following studies are necessary:
1- Statistical analysis of simulated models and preparation of a geomorphometric basis (frequency analysis, hypsometric distribution and characterization of correlation values) 2- Extraction of units of basis of land lays 3- Study of statistical aspects and adjacent morphology units 4. Analysis of existing profiles (electronic maps and examination of slope, curvature and shape elements) 5. Step-by-step tests of land 6. Modification of methods and classification of process
Aliakbar Rasuli
Volume 1, Issue 3 , August 1991, , Pages 50-55
Abstract
In this paper, we try to emphasize on the importance of new display systems by reviewing educational and research limitations and deficiencies of traditional methods of displaying land features. The three-dimensional representation of the GIS and its practical aspects forms the next section. The main ...
Read More
In this paper, we try to emphasize on the importance of new display systems by reviewing educational and research limitations and deficiencies of traditional methods of displaying land features. The three-dimensional representation of the GIS and its practical aspects forms the next section. The main part of the paper is related to three-dimensional simulated digital-graphic models of land features. In the same vein, cartographic and computer techniques in creating three-dimensional images are of interest. In the last section, we make conclusions and suggestions after a brief review of the applications of visual simulated models in geology and geomorphology. Keywords and main subjects of the article include:
Map, GIS (Geographic Information Systems), GIS 3D Modeling, Modeling, Cartographic and Computer Techniques, Digital-Graphic Models, Land Features, D.E.M, Application of Models in the Earth Sciences.
