GEOGRAPHICAL DATA
Year:2016 | Volume:25 | Issue:97|Papers Count:10

The main purpose of this paper is using the probablity models, Auto Regressive Moving Average (ARMA) in order to modeling of daily position time series of permanent GPS station. The daily position time series of LLAS site in Southern California region from SCIGN array that were active during January 1,2000 to Dec 30, 2006 are evaluated for analysis and determinig of daily position time series. According of daily position time series, a site motion model is used to estimate simultaneously geodetic parameters such as: linear trend, annual harmonics, semi annual harmonics and offsets. In each daily position time series, model parameters are estimated using weighted least squares. In this study, Auto Correlation Function (ACF) and Partial Auto Correlation Function (PACF) are used as study tools for identification of behavior of daily position time series of permanent GPS station. These functions provide consideration of correlations between daily positions of daily time series. Moreover, Akaike Information Criterion is used to identify model orders, because some kind of ARMA model may appropriate for a daily position time series of GPS station. In this study, some numerical results shows that a model order from (1, 1) is appropriate for direction N of permanent GPS station. Probabality model of ARMA (2, 1) is best model for direction E and a model order from (1, 1) is suitable for direction U. In the final step, a daily position time series of LLAS permanent station were predicted for seasonal component.

Accidents, crisis and then search, aid and rescue together form a cycle that repeats for several times in a country like Iran. In this cycle, commonly known as crisis management cycle, from its early stages i.e. determination of risk for regions up-to post-crisis and recovery stages that are final ones in such a cycle, we are constantly facing data and outputs which are somehow related to position and location. Gathering data both in pre and post stages of a crisis will not be a very difficult task, as the damaged society is then almost relieved of panic and therefore resources permit the authorities in charge to gather information as required.However, during the crisis and as long as the society is suffering critical conditions, it will be very useful and obviously difficult to gather information such as depth of damages, damaged regions, regions with risk potential, also dispersion of damages, resources and facilities, and etc.Thus, considering lack of tools and appropriate technology in the country for gathering information during crisis conditions, this research has focused on gathering information in crisis management response phase. In this regard, concepts of Telegeoinformatics (TGI) and its various architectures were presented and continued with designing a system for gathering information during earthquake crisis. Finally, an emergency response system was designed and was presented as a software package. Moreover, the model and software of this system was presented in UML for further development by other researchers that are studying in the same fields, which resulted in presentation of suggestions for development of this system using other technologies.

With the purpose of suitable environmental planning, identification and evaluation of future climatic changes are necessary in order to adaptation and mitigation its effects. In the present study, SDSM model, was successfully calibrated and validated (1981-2010) to comparative analysis and explore future changes in maximum temperature of Iran for the future periods of 2041-2070 and 2071-2099 under A2, B2, A1B & B1 scenarios from HADCM3 & CGCM3 models, relative to the baseline period of 1981-2010. In other words, with regard to the uncertainty for the daily maximum temperature of future data Downscaling was performed onto 7 synoptic stations as the climatic representatives of Iran. Analysis uncertainty of outputs showed that CGCM3 model under scenario B1 between all different models-scenarios has been the best performance in simulations of future temperature. Also, By analyzing future temperature determined that the average temperature of Iran will increasing in the middle decades and at the end of the twenty-first century, between 1 and 2oC, but this increase of temperature will be higher based on different scenarios of Hadcm3 model on compared to CGCM3 model. Also From the perspective spatial distribution based on outputs of all models-scenarios, The lowest increase of temperature have been observed in Low altitude and lowland stations, particularly in the southern coasts (Bandar-Abbas station) and vice versa increase of temperature is maximized ,whatever we are moving Highlands and mountainous regions of Iran (Tabriz station). In total, important factors contributing to future changes of temperature can be classified in three groups that include the following factors: altitude, latitude and atmospheric humidity. So that based on all outputs of the models-scenarios, Stations that are located within the northern elevations, have demonstrated the greatest increase in temperature on compared to stations that are low-altitude and adjacent to the southern coast of Iran.

Simplification and automation of the process of visual and geometric reconstruction is one of the issues considered in 3D modeling of environment, especially in urban areas. A stereo camera, as the positions of its lenses are fixed relative to each other, can be used to facilitate the modeling process. This article shows that using stereo camera calibration data, producing 3D environment model can be facilitaded without needing for matching process, especially in the areas that the matching has problem because of unsufficient information need for it. Moreover, using camera calibration information, geometric information and depth map of the environment can be extracted and produced without the need to define the specified scale between features. In the following, the results of investigations carried out for the reconstruction of urban environment are expressed.

Aerial images are systematically utilized in most scientific contexts to undertake exploration and measurement operations. Image matching techniques for the acquisition of the ground truth in order to create thematic maps have been always faced difficulties and challenges. In this research, the LPS module from the ERDAS Imagine 9.2 software was used to develop geomorphological landforms maps of the Harzand Chai watershed. The methodology used was based on analytical photogrammetric techniques (Two Dimension Affaine) using aerial photographs (1:40000). Harzand Chay watershed geomorphological landforms maps, were prepared using both traditional and photogrammetry methods. Prepared map by photogrammetrical method (Two Dimension Affaine), was compared after field visiting and matching type facies with the acquisition of the ground truth, with the map which prepared by conventional method that is used for creating thematic maps in our country. Geomorphological landforms map has been prepared for the test to assess 100 points on maps provided by the software ERDAS Imagine 9.2 about 62 points of the set and then using ground positioning system (GPS) were harvested and the characteristics of each were done. Stratified Random Sampling and test method was used by ERDAS Imaginge 9.2 for examin two prepared maps.The resultant map was then matched with the real features and compared with the map developed by traditional methods used in the thematic mapping process in Iran. According to the findings of the statistical test, the percentage of the total accuracy for the geomorphological landforms map developed by the analytical photogrammetry technique was %95. The Kappa Index value for this map was estimated to be 0.9. These values for the geomorphological landforms map created by the conventional method were obtained %84 and 0.76 respectively. Therefore, the geomorphological landforms map created by the analytical photogrammetry was selected as the best representation of the geomorphological features of the Harzand Chai watershed.

Coordinate systems transformation has an important role in mapping activities, geodesy and spatial science. New and efficient methods are needed in order to increase the accuracy in the transformation between these systems.The main purpose of this article in the first part, is a local coordinates transformation in Isfahan City to UTM coordinates and vice versa. This method is based on the combined scale factor. So, the coordinates of 500 GPS stations in Isfahan City was used, and with reduction of distances on the surface of the earth to the map, coordinates of the GPS points in the local system was calculated. Study on changing of combined scale factor for the GPS points of Isfahan City shows that if a unit scale factor is used for whole the city, in long lengths occurs a few decimeter differences and it is not suitable for accurate mapping.LIDAR is a mature remote sensing technology which can provide accurate elevation data for both topographic surfaces and above-ground objects. So in the second part of the article, we presented an algorithm to provide height interpolation for the points in the passage network of Isfahan City by using LIDAR data, because the inverse transformation from local system to UTM using new methods such as Rational Functions, needs vertical component in addition to horizontal position of points.A height bias of 30 centimeter has been detected in the LIDAR data using GPS control points. After removal of this systematic component, the final RMSE of LIDAR heights are 43 centimeters.

Khorasan Razavi province with neighboring Afghanistan and Turkmenistan in addition to cultural and economic consequences in border towns, particularly in the strengthening of the security challenges facing the city’s passive defense. The most important factors related to the security challenges in these border towns, the lack of full identification of specific geographical factors and geomorphologic characteristics of the topography of the principles and strategies for urban passive defense. Identifying and environmental constraints can be a more effective role to play in these cities design principles and passive defense. Zavyn city in North Khorasan province is considered one of the towns close to the border with special topographic features. The goal of this study was to examine the topographic and geomorphologic approach of passive defense and security challenges and problems topographic analysis of the study area is the use of GIS. The results indicate that the formation geomorphologic powers topography and urban form of the current fragmented and decentralized Zavyn city, in such a way that the core triple Zavyn in terms of defense, by strengthening and empowering tissue and converting linear paths access to the network graph in the status quo is acceptable.

Nowadays, we are observing a huge revolution in the use of mobile equipment in all aspects of human life. They greatly facilitate our daily life by their numerous capabilities such as powerful processors and various embedded sensors. Reviewing the history of Geographic Information Science (GIS),one can clearly recognize that real time spatial processes have been the most important concern over the years. On the other hand, data gathering phase is the most time and cost consuming phase in most practical projects. Using traditional way to perform data gathering phase, not only causes some noticeable problems such as: the difficulty of carrying paper maps, inevitable human made mistakes; but also create a deep gap for hitting the main goal of performing a real time spatial process. In this study, by developing a context aware mobile information system that takes advantage of distributed architecture, we try to deal those problems. Our ultimate goal is to replace our developed system by traditional methods for gathering spatial and descriptive data about nuisance jobs in Kermanshah, Iran. We assess and compare our system with traditional methods by comparing their results for collected data in 4 districts in a city by different groups of users. Statistical tests prove our developed system has more reliability and efficiency in compare with traditional methods. At the end, the tendency of about 92% of user to use our system in compare with traditional methods is another measurethat indicates our success in achieving the ultimate goal of this study.

In this study, the effects of induction of Sea Surface Temperature (SST) on surface wind speed were investigated in the South Caspian region (Mazandaran province). To this study, Sea Surface Temperature data by AVHRR sensor of NOAA satellite and surface wind speed data by QuikSCAT Satellite. was collected in an area with dimensions of 2x3 degree after Analysis of satellite data of Sea Surface Temperature, monthly and seasonal variations of these data in this area were drawn with Tecplot software. It was show that the average seasonal (spring and summer) at the eastern coast of the South Caspian is 0.80% more than the western regions. For studying the effect of induction of sea surface temperature on surface wind speed, for stations A and D (in western region), Band C (in eastern region) has consider in South Caspian Sea. The time series of temperature, time series of temperature difference between the two stations, time series of wind speed and time series of wind speed differences were plotted between for stations A, D and B, C since 2000 to 2005 in the spring and summer seasons and compared. Results show that with increasing temperature difference between D, A and B, C stations, the speed difference increases 66% and 80% in summer and spring seasons respectively. Since has been reduced activity of atmospheric systems in the summer and spring seasons, temperature difference between for stations has considerable effect on improving the wind speed difference. Average of difference wind speed at stations in the spring is, 0.7m / s and in the summer, 1.37m /s.

Due to changes in landuse that is done mostly by human activities, change detection of landuse and assessment of theirs environmental impact is essential, in order to future planning and manage the resources. Therefore the aims of this study are monitoring, detection and trending of landuse changes in Abarkooh basin (1976-2014), in order to assess the environmental issues such as human stress on earth without considering tolerance capacity, and identify the regions having management stress. In this way, the data of Landsat satellite images, sensors MSS (1976), TM (1990), ETM+ (2000 and 2006) and OLI (2014); and techniques of remote sensing, such as supervised classification and accuracy assessment of post classification were used to identify the type of land use. Also, principal component analysis, tasseled cap and Image differencing were used to monitor the landuse changes. The Classification results show the seven types of landuses, including urban, agriculture, bare, rock, range, clay and playa lands, and which 2014 year, with kappa values of 82.18%, and total accuracy of 0.76 have the highest accuracy of classification. The trending result of landuse changes indicate the increasing trend of area in the range (5.65%), rock (2.52%), bare (3.63%) and agriculture (1.04%) lands, and the downward trend of area in the urban (4.33%), clay (6.89%) and playa (6.03%) lands, respectively. From the base of principal component analysis and tasseled cap functions, respectively 1.748% (306.4912 km2) and 3.989% (699.961 km2) of the study area has been faced with positive changes of landuse, but the general trend of positive changes classes is increasing. The most of the changes are devastating and are according to the human community centers such as Abarkooh and Mehrdasht cities. It is evident that continuation of this trend, in the near future, converts Abarkooh basin into a dead and inactive ecosystem that has no potential ecological and biological of production.