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Archiv: Juli 2009

Introduction
Less than ten days ago, a deadly earthquake devastated the Iranian city of Bam, killing more than 30,000 people and injuring another 50,000. It was one of the deadliest natural disasters in modern Iranian history, and similar in destruction to the Roudbar earthquake in northern Iran in 1990. Historical information and all available records show that approximately 130 large earthquakes have taken place in most parts of Iran. Considering the high seismicity of Iran, a comprehensive hazard reduction program was launched in Iran in 1991, but the effectiveness of the measures have been limited by lack of adequate funding and institutional coordination. There is no lack of probabilistic studies on the seismicity of the country as well as fault studies. Comprehensive studies have been performed by Berberian (1999, 2001), Amiri et al. (2003), Sarkar et al. (2003), Modarressi (2002), Walker (2002) and Tehranizadeh (2001, 2002). A more detailed bibliography is presented at the end of this document.

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Aerial and Spaceborne Ten-Year Trends
USGS 2008-2018 Africa Remote Sensing Study

Africa is a continent as large as China, India, Argentina, the United States of America and Western Europe combined. With a population of over 922 million (as of 2005 and projected by the United Nations to reach one billion by 2010) Africa has four main regional languages (i.e. English, French, Portuguese and Arabic) and almost 200 local languages. The three largest countries in Africa in terms of population are Nigeria (133 million as of 2006), Egypt (79 million) and Ethiopia (77 million). Africa faces some of the greatest geospatial data needs and issues found anywhere in the world, considering the high levels of poverty, deforestation and desertification, coupled with the political and societal unrest in individual countries. The USGS 2008 Africa Remote Sensing Study received an excellent response rate of 377 respondents from over 30 countries; as compared to a 2005 GIS study in Africa that focused on 600 qualified GIS professionals and resulted in 62 responses from 18 countries. Much of that low response was due to lack of telecommunication infrastructure. The USGS 2008 survey is an excellent sign that wireless technology is making some advances and allowing greater access to the internet and to geospatial data, although infrastructure is still an issue in Africa.

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Abstract: The semi-arid region of the Aurès presents an undeniable diversity of flora and fauna, however weather conditions and actual adverse anthropogenic, caused degradation of the physical environment, which have the form of a regression in the natural forest cover. The objective of this study is to determine the contribution of satellite images in detecting changes in land use and monitoring of the degradation processes in the southern part of the Aurès region. As far as that goes, we used images: Landsat ETM + for 2001 and TM 1987.These last cover the southern region of the Aurès which presents a landscape exposed to the phenomena of degradation including forest Beni-Mloul, Dj.Mezbel and Dj khaddou Ahmar, characterized by endemic species. The adopted step is to treat multi-dates satellite imagery by the method of supervised classification of Maximum likelihood to see global changes of land use that have occurred in this area.

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ABSTRACT

The possibility of using high resolution satellite data on a GIS platform for fast and low-cost map upgrading and digital cartographic database-building over remote areas in Africa is demonstrated. Using just one LANDSAT TM composite image, in combination with DEM (digital elevation model) and the author’s GPS data, a series of base and derived maps (hydrography, territorial boundaries, villages location, road network, relief) was obtained in a digitized, highly accurate, updated and upgradeable GIS-friendly format for the remote Kayamba Chiefdom in Congo. From these digital layer maps, a set of quantitative cartographic metrics (coordinates, distance, length, area, slope, aspect, etc.) was reliably deduced. All these fi ndings provide a solid base for further quantitative eco-climatic analysis or land/resources management and planning for the Chiefdom. Ground truth data are determinant in defi ning and/or identifying the surface features embedded in the satellite imagery. I recommend this analysis approach for those remote areas in developing countries where a full-scale ground survey is too costly or technologically too demanding.

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Abstract
Background: Various geographic information systems (GIS) are now widely used to map the distribution of diseases and mortality. However, the mapping of raw mortality rates has been found to be inappropriate since it does not account for the spatial heterogeneity of the population at risk. Bayesian techniques have therefore been suggested as a solution to the problem. Methods: Annual mortality rates for each of the 39 villages of the study area in the Kossi Province in northwest Burkina Faso were calculated using midyear populations of children under five. Two mapping techniques were then used. Firstly, the GIS software ArcView was used to map the crude mortality rates. Secondly, the data were smoothed by the method of empirical Bayes estimation. The geostatistical prediction method of Kriging was then used to spatially interpolate the data for successive years. Results: No spatial pattern is identifiable from the circles representing mortality rates drawn on the map using ArcView. The circles are scattered over the study area and comparing annual distributions between them is difficult. The maps produced by the Bayesian technique also do not show a clear spatial trend pattern. However, they indicate the tendency of villages in the northeastern region to produce higher incidence or risk values, confirming the results of an earlier study reporting a significant cluster of high childhood mortality in the same area.

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Full Length Research Paper

Proper use from water resources, especially in arid and semi arid of Iranian rangeland are very important. In this area water is one of a valuable ecosystem component. The study was conducted in Ghareh Aghach watershed region is located, Isfahan province, in central part of Iran. Four criteria’s of water quality, water quantity, water distance and livestock information were integrated to water resources suitability for goats grazing. According to the results, water distance and accessibility to water is a most declining factor for suitability. A quality and quantity factor is a no limiting factor in part of study area. The results show that from 7158.69 ha of studied rangelands, 6245.93 ha (87.25%) classified as S1 class (with no limitation), 810.58 ha (11.32%) classified as S2 class (with low limitation), and 102.3 ha (1.43%) classified as N class (non suitable). Based up on slope classes, areas that far from water point more than 75% of slope is not suitable and less than 15% are very suitable. Good distribution of water resources increases water suitability and cause better and monotonous utilization of rangeland.

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Abstract: This study represents a part of an ongoing research program to evaluate the lithologic mapping capabilities of NigeriaSat-1. Rafin Gabas is located in Nasarawa state and falls within the Younger Granite province of Nigeria. Wolframite and cassiterite have been found to occur within this area.The topographical map of the study area was generated from the SRTM (Shuttle Radar Topography Mission Data). The DEM was converted into a contour map using the ERDAS and ArcView softwares. The NigeriaSat-1 image of the area was subjected to various image processing techniques such as edge enhancement, Principal component analysis and filtering. Samples from wolframite-bearing-quartzite-veins were analysed and old tin mines were studied. The various ancillary data were integrated in ILWIS software. Geological information such as lithological boundaries and lineaments were derived from the NigeriaSat-1 image. The lineaments were found to occur in the NE-SW direction and they range in length from 300 Km to 2.5 Km and some cut across rock boundaries. The results of the XRF analysis show an average of 62% Wo . Tailings from the old mines were observed to 3 contain some amounts of Cassiterite which could be reworked. The various data generated were integrated in a GIS environment and a mineral probability map was produced.

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2009 17 Jul

The HIVmapper

Abgelegt unter: Gis Anwendungen | RSS 2.0 | TB | Tags: , | Keine Kommentare

The HIVmapper is an interactive GIS mapping tool which allows users to quickly create maps based on MEASURE DHS data found in the HIV/AIDS Survey Indicators Database.

Use maps to tell stories and explain trends. For example, maps can help to describe the HIV situation in Tanzania. Below are four maps that describe HIV prevalence in Tanzania and in the region. Click on thumbnail images to see maps in HIVmapper.

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INTRODUCTION
The success of tourism in any country depends on the ability of that country to sufficiently develop, manage and market the tourism facilities and activities in that country (Briassoulis and Straaten, 1999). In the United Arab Emirates (UAE), tourism is one of the industries with the strongest effect on the economy because it helps in developing other sectors. According to statistics supplied by Department of Economic Development in the Emirate of Ras al Khaimah (RAK) (2007), tourism in the Northern part of the UAE contributes about two percent to the Gross Domestic Product (GDP) (Department of Economic Development, 2007). The tourism sector is estimated to have generated 19 billion US dollars in 2007 for the UAE (Alittihad, 2008). The UAE Government in her quest to diversify her mono-cultural economy, which is heavily dependent on petroleum export, has decided to take some measures to promote travel and tourism (Ministry of Economy, 2007). The aims of these measures to make the UAE the ultimate tourism destination in the Middle East and to make tourism one of the greatest foreign exchange earners in an oil dependent economy.

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Remote sensing is the science and art of obtaining information about an object through the analysis of data
acquired by a device that is not in contact with the object (Lillesand and Keifer, 1994). Remotely sensed data can be of many forms, including variations in force distribution, acoustic wave distribution or electromagnetic energy distributions and can be obtained from a variety of platforms, including satellite, airplanes, remotely pilot vehicles, handheld radiometers or even bucket trucks. They may be gathered by different devices, including sensors, film camera, digital cameras, video recorders. Our eyes acquire data on variations in electromagnetic radiations. Instruments capable of measuring electromagnetic radiation are called sensors. Sensors can be differentiated in two main groups: Passive sensors: without their own source of radiation. They are sensitive only to radiation from a natural origin. Active sensors: which have a built in source of radiation. Examples are Radar (Radio detection and ranging) and Lidar (Light detection and ranging) systems.

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