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Therapeutic strategies targeting CD47-SIRPα signaling pathway in gastrointestinal cancers treatment
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作者 Zhengping Che Wei Wang +1 位作者 Lin Zhang Zhenghong Lin 《Journal of Pharmaceutical Analysis》 2025年第1期97-113,共17页
Gastrointestinal(GI)cancers are prevalent globally,with leading incidence and mortality rates among malignant tumors.Despite notable advancements in surgical resection,radiotherapy,and chemotherapy,the overall surviva... Gastrointestinal(GI)cancers are prevalent globally,with leading incidence and mortality rates among malignant tumors.Despite notable advancements in surgical resection,radiotherapy,and chemotherapy,the overall survival rates remain low.Hence,it is imperative to explore alternative approaches that enhance patient outcomes.Cluster of differentiation 47(CD47),serving as an early diagnostic marker,is predominantly overexpressed in GI cancers and associated with poor prognosis.Targeting the CD47-signal regulatory protein alpha(SIRPa)signaling pathway may provide a novel strategy for GI cancers treatment.This study summarizes current knowledge of the structure and function of CD47 and SIRPa,their roles in signaling pathways,the prognostic significance of CD47,therapeutic strategies targeting the CD47-SIRPα signaling pathway in GI cancer,and highlights key issues for future investigations. 展开更多
关键词 CD47-SIRPα Signaling pathway Immune checkpoint blockade IMMUNOTHERAPY GI cancers
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路易斯碱-硼自由基促进的邻苯二甲酰亚胺类羧酸酯的Giese反应和Barton脱羧反应研究 被引量:5
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作者 靳继康 张凤莲 汪义丰 《化学学报》 SCIE CAS CSCD 北大核心 2019年第9期889-894,共6页
邻苯二甲酰亚胺羧酸酯的自由基脱羧是产生碳自由基的一类重要方法.开发了一类路易斯碱-硼自由基促进的邻苯二甲酰亚胺羧酸酯的自由基脱羧新方式,产生的烷基自由基经过加成到缺电子烯烃上或者进一步还原得到Giese反应和Barton脱羧产物.... 邻苯二甲酰亚胺羧酸酯的自由基脱羧是产生碳自由基的一类重要方法.开发了一类路易斯碱-硼自由基促进的邻苯二甲酰亚胺羧酸酯的自由基脱羧新方式,产生的烷基自由基经过加成到缺电子烯烃上或者进一步还原得到Giese反应和Barton脱羧产物.该反应条件温和,适用范围广泛,多种一级、二级和三级烷基羧酸包括具有生物活性的天然产物和药物分子都能够较好地适用,为邻苯二甲酰亚胺羧酸酯的自由基脱羧提供了无过渡金属参与的具有普适性的新方式. 展开更多
关键词 对二甲氨基吡啶-硼自由基 自由基脱羧反应 giese反应 Barton脱羧还原 自由基化学
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中心手性金属铑配合物催化的不对称光诱导Giese自由基加成反应
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作者 陈亮 胡良建 +2 位作者 杜宇 苏伟平 康强 《有机化学》 SCIE CAS CSCD 北大核心 2020年第11期3944-3952,M0014,共10页
报道了一种可见光驱动的双功能中心手性金属铑配合物催化的不对称自由基加成反应,由对胺基苯乙酸生成的对胺基苄基自由基对α,β-不饱和酰基咪唑进行立体选择性的1,4-加成,以中高收率和高对映选择性合成了一系列加成产物.该反应具有对... 报道了一种可见光驱动的双功能中心手性金属铑配合物催化的不对称自由基加成反应,由对胺基苯乙酸生成的对胺基苄基自由基对α,β-不饱和酰基咪唑进行立体选择性的1,4-加成,以中高收率和高对映选择性合成了一系列加成产物.该反应具有对映选择性高、反应条件温和、操作简单等特点.根据对双功能中心手性金属配合物催化的研究和文献报道,提出了一个合理的反应机理. 展开更多
关键词 可见光催化 双功能手性铑配合物 giese自由基加成反应 对胺基苄基自由基
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Integration of Digital Technologies into Underground Utility Asset Management
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作者 Eronmonsele Esekhaigbe Emrah Kazan Mumtaz Usmen 《Open Journal of Civil Engineering》 2020年第4期403-428,共26页
Installation, detection, maintenance, mapping, and management of underground utility assets present challenges to owners, engineers and contractors. Industry-wide practices include the use of geophysical and similar t... Installation, detection, maintenance, mapping, and management of underground utility assets present challenges to owners, engineers and contractors. Industry-wide practices include the use of geophysical and similar technologies to determine depth and location, and 2D as-built plans integrated with GIS databases for information management. The feasibility of incorporating 3D BIM models of the subsurface to replace the 2D plans to improve visualization and data management is examined in this paper. Obtaining an accurate image of the underground infrastructure would help minimize excavation accidents due to equipment-utility collisions and prevent property damage. Further, the inclusion of automated data collection and sharing features realized through BIM technology can enhance operations of smart cities. The research methodology consists of a state-of-the-art review of the current underground utility management systems, combined with statistical analysis of survey responses received from utility providers and one-call centers in the U.S. Three categories of utility practices are identified based on the level of digital technology integration. It is found that a vast majority of utility firms have adopted GIS databases with 2D plans, depth and other asset information, while a smaller percentage of providers have achieved full GIS-BIM in<span style="font-family:Verdana;">tegration, incorporating a wide range of asset data. Future progress on</span><span style="font-family:Verdana;"> broader implementation appears to be constrained by the digital literacy of personnel </span><span style="font-family:Verdana;">and high costs of technology acquisition and application. A three-step frame</span><span style="font-family:Verdana;">work for converting 2D plans to 3D BIM models is also presented and discussed. The process model proposed for this purpose allows the utilization of commercially available software with minimal need for additional coding.</span> 展开更多
关键词 Underground Utilities Asset Management Digital Technologies GIS Database 3D BIM Model
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Application of GIS and GPS technologies in managing a statewide groundwater monitoring and assessment network in the state of Minnesota,USA
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《Global Geology》 1998年第1期85-85,共1页
关键词 GIS GPS Application of GIS and GPS technologies in managing a statewide groundwater monitoring and assessment network in the state of Minnesota USA USA
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Preparation of earthquake-triggered landslide inventory maps using remote sensing and GIS technologies:Principles and case studies 被引量:32
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作者 Chong Xu 《Geoscience Frontiers》 SCIE CAS CSCD 2015年第6期825-836,共12页
Inventory maps of earthquake-triggered landslides can be constructed using several methods,which are often subject to obvious differences due to lack of commonly accepted criteria or principles,To solve this problem,t... Inventory maps of earthquake-triggered landslides can be constructed using several methods,which are often subject to obvious differences due to lack of commonly accepted criteria or principles,To solve this problem,the author describes the principles for preparing inventory maps of earthquake-triggered landslides,focusing on varied methods and their criteria,The principles include the following key points:all landslides should be mapped as long as they can be recognized from images;both the boundary and source area position of landslides should be mapped;spatial distribution pattern of earthquake-triggered landslides should be continuous;complex landslides should be divided into distinct groups;three types of errors such as precision of the location and boundary of landslides,false positive errors,and false negative errors of earthquake-triggered landslide inventories should be controlled and reduced;and inventories of co-seismic landslides should be constructed by the visual interpretation method rather than automatic extraction of satellite images or/and aerial photographs,In addition,selection of remote sensing images and creation of landslides attribute database are also discussed in this paper,Then the author applies these principles to produce inventory maps of four events:the 12 May 2008 Wenchuan,China M_w 7.9,14 April 2010 Yushu,China M_w 6,9,12 January 2010 Haiti M_w7.0,and 2007 Aysen Fjord,Chile M_w 6.2,The results show obvious differences in comparison with previous studies by other researchers,which again attest to the necessity of establishment of unified principles for preparation of inventory maps of earthquake-triggered landslides. 展开更多
关键词 Earthquake-triggered landslides INVENTORY PRINCIPLE GIS Aerial photographs Satellite images
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Applications of RS, GIS and GPS technologies in research, inventory and management of wetlands in China 被引量:14
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作者 CUI Li-juan Anna van Paddenburg ZHANG Man-yin 《Journal of Forestry Research》 SCIE CAS CSCD 2005年第4期317-322,共6页
This paper introduces the state of waterlands in China and discribes the applications of Remote Sensing (RS), Geographical Information System (G1S) and Global Positioning System (GPS) in wetland research, includ... This paper introduces the state of waterlands in China and discribes the applications of Remote Sensing (RS), Geographical Information System (G1S) and Global Positioning System (GPS) in wetland research, including land-coverclassification and change detection, wetland evolutionary processes, landscape-change analyses, channel migration, flood and wetlands resource monitoring and spatial quantitative analyses/modeling, ecosystem service evaluation, ecological processes and risk assessments, disease control, water quality monitoring/modeling, pollution monitoring/modeling, wetlands hydrology, wetland information systems and WebGIS. The limitations and needs for optimal use of these technologies are discussed, such as the limited advanced technical knowledge and skills, low awareness and capacity, unclear link between GIS output and policy making, lack of supporting policies and standards, lack of a wetlands geo-information networklimite, and the use of these techniques in wetland research. It is suggested that for realising true applications of RS, GIS and GPS technologies, the availability, accessibility, reliability, homogeneity, and continuity of wetlands-related geo-information enabling environment, policies and standards, and funding are needed. 展开更多
关键词 Geographic Information System (GIS) Remote Sensing (RS) Global Position System (GPS) 3S WETLAND
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Developing conservation strategies for Pinus koraiensis and Eleutherococcus senticosus by using model-based geographic distributions 被引量:4
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作者 Jizhong Wan Chunjing Wang +5 位作者 Jinghua Yu Siming Nie Shijie Han Juzhao Liu Yuangang Zu Qinggui Wang 《Journal of Forestry Research》 SCIE CAS CSCD 2016年第2期389-400,共12页
We described potential changes in the geo- graphic distribution and occurrence probability of Pinus koraiensis Sieb. et Zucc. and Eleutherococcus senticosus (Rupr. et Maxim.) Maxim. in the counties of northeast Chin... We described potential changes in the geo- graphic distribution and occurrence probability of Pinus koraiensis Sieb. et Zucc. and Eleutherococcus senticosus (Rupr. et Maxim.) Maxim. in the counties of northeast China. This information was used to identify priority areas for protection and provide protection and management recommendations within each studied county. The two species were mapped in 2884 study plots throughout this region over a 4-year period (38°40'N-53°30'N, 115°05'E- 135°02'E). We used the species distribution models (Maxent), systematic conservation planning models (Marxan), and Geographic Information Systems (ArcGIS 10.0). The distributions of two species were correlated in the study area, enabling unique and economically viable joint conservation measures to be implemented. Three models were combined to identify feasible priority con- servation sites. We used local spatial statistics to assess all identified conservation areas in relation to potential climate change based shifts in the geographic distribution of the two species. Model-based conservation strategies were used to identify effective measures to protect and utilize these two tree species in the study region. This study pre- sents a novel technique for assessing wild plant distribu- tions, in addition to serving as a model for the conservation of other species within the framework of general forest management, ecological construction, and geographical surveying. 展开更多
关键词 Eleutherococcus senticosus GIS MODELING Pinus koraiensis
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Remote Sensing and GIS as an Advance Space Technologies for Rare Vegetation Monitoring in Gobustan State National Park, Azerbaijan 被引量:1
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作者 Yelena M. Gambarova Adil Y. Gambarov +1 位作者 Rustam B. Rustamov Maral H. Zeynalova 《Journal of Geographic Information System》 2010年第2期93-99,共7页
This paper describes remote sensing methodologies for monitoring rare vegetation with special emphasis on the Image Statistic Analysis for set of training samples and classification. At first 5 types of Rare Vegetatio... This paper describes remote sensing methodologies for monitoring rare vegetation with special emphasis on the Image Statistic Analysis for set of training samples and classification. At first 5 types of Rare Vegetation communities were defined and the Initial classification scheme was designed on that base. After preliminary Statistic Analysis for training samples, a modification algorithm of the classification scheme was defined: one led us to creating a 4 class’s scheme (Final classification scheme). The different methods analysis such as signature statistics, signature separability and scatter plots are used. According to the results, the average separability (Transformed Divergence) is 1951.14, minimum is 1732.44 and maximum is 2000 which shows an acceptable level of accuracy. Contingency Matrix computed on the results of the training on Final classi- fication scheme achieves better results, in terms of overall accuracy, than the training on Initial classification scheme. 展开更多
关键词 REMOTE SENSING GIS Seperability Classification
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THE STRATEGIES OF INTEGRATING SPATI AL DATA ANALYSIS AND GIS
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作者 MAO Zheng-yuan LI Lin 《Chinese Geographical Science》 SCIE CSCD 2002年第3期233-237,共5页
The gap between SDA(Spatial Data Analysis)and GIS(Geographical Information Systems)existed for a long time.Presently this problem still remains in spite of a lot of theore tical and practical studies which tr y to fin... The gap between SDA(Spatial Data Analysis)and GIS(Geographical Information Systems)existed for a long time.Presently this problem still remains in spite of a lot of theore tical and practical studies which tr y to find the solu-tion for it.The research background and current situation about how to in tegrate SDA and GIS are introduced at first.The main idea of this article is to make su re what is the best scheme to bridge th e gap between SDA and GIS and how to design it.There are a lot of factors to influ ence the standards to assess such a sc heme,for instance,the attitude of users and GIS developers,the framework and related functions of current available GI S software in the market and so on.But the two most important ones of them are effic iency and flexibility of the scheme i tself.Efficiency can be measured by the conve-nient extent and temporal length when it is used for carrying out SDA.Flex ibility means users can define their own SDA methods.The best integration schem e should satisfy the two standards at the same time.A group of functions,which can be combined to implement any SDA meth od,are defined in order to design such an integration scheme.The functio ns are divided into five classes according to their properties. 展开更多
关键词 GIS spatial data analysis integrating strategy open GIS framework
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Estimation of Gravitational Processes in Mountain Areas Using GIS Technologies
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作者 Sofia Gavrilova T.G.Glazovskaya 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期284-284,共1页
Nowadays building and engineering in mountain areas are developing rapidly.But there are many natural hazards which can cause casualties or serious damage to the constructions.But for large territories it is very diff... Nowadays building and engineering in mountain areas are developing rapidly.But there are many natural hazards which can cause casualties or serious damage to the constructions.But for large territories it is very difficult to get good and exact field data to estimate the activity and level of risk of the hazard. That is why we create a method of estimating territory by using satellite data.We appraise 展开更多
关键词 AVALANCHE risk HAZARD GIS Landsat ETM+ SRTM
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Architecture and critical technologies of seismic information system in CTBT verifi-cation
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作者 郑学锋 沈钧毅 +4 位作者 靳平 郑江铃 孙鹏 张慧民 王同东 《Acta Seismologica Sinica(English Edition)》 EI CSCD 2006年第5期588-595,共8页
Seismic monitoring is one of the most important approaches for ground-based nuclear explosion monitoring. In order to improve the monitoring capability for low magnitude seismic events, a seismic information system wa... Seismic monitoring is one of the most important approaches for ground-based nuclear explosion monitoring. In order to improve the monitoring capability for low magnitude seismic events, a seismic information system was developed by using the technologies of geographic information system and database. This paper describes the designing and critical technologies of the Seismic Information System in CTBT Verification developed based on ArcGIS and ORACLE platforms. It is a combination of the database storage framework, application programming interface and graphic application software for users to meet their monitoring objectives. Combining the ArcSDE Geodatabase, RDBMS ORACLE and ArcObjects developing technique on COM, not only the multi-sources data has been seamlessly integrated, but also the most functions of ORACLE, for example, consistency, concurrent access, security mechanism, etc, have been reserved. For easy access to the information system we develop two different mechanisms. The first is a menu-driven internal system that is run on NT platforms. The second access mechanism is based on LAN and easily accessible by any web browsers. 展开更多
关键词 seismic monitoring CTBT DATABASES nuclear explosion monitoring GIS
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CLUE-S model based on GIS applied to management strategies of territory with oil wells—Case study:Santa Elena,Ecuador
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作者 Gricelda Herrera-Franco Paulo Escandón-Panchana +1 位作者 F.J.Montalván Andrés Velastegui-Montoya 《Geography and Sustainability》 2022年第4期366-378,共13页
Some cities worldwide have oil wells directly affecting the management of the territory.For example,La Libertad and Salinas districts contain 467 oil wells in urban areas representing a major land-use planning challen... Some cities worldwide have oil wells directly affecting the management of the territory.For example,La Libertad and Salinas districts contain 467 oil wells in urban areas representing a major land-use planning challenge.The objective is to apply the CLUE-S land use model in coastal cities with oil wells(Salinas-La Libertad),using geographic information systems considering environmental and security characteristics for territorial development.The stages of the study are:i)classification and categorisation of oil wells;ii)application of the GIS-CLUE-S method and visualisation of land use dynamics;iii)use the SWOT-TOWS matrix,for the analysis of the situation and the main factors affecting the territory.The results indicate high vulnerability in many urban sectors and those close to the coastline.Furthermore,the CLUE-S analysis shows that the population growth in the urban sector is close to oil well areas,making it a complex pole of human-industry interaction that impacts the management of the territory.This study synthesises three technical aspects:some oil wells do not comply with municipal ordinance regulations;identification of vulnerable zones due to environmental and security factors,which recommends a territorial reordering policy;as well as an education plan for the application of territorial ordering policies,with awareness and sustainability projections. 展开更多
关键词 Land use VULNERABILITY SUSTAINABILITY GIS Dinamica EGO
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Use of Spatial Technologies to Study the Winds' Directions in Rub' AI-Khali Desert, Saudi Arabia
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作者 Ali Madan AI-Ali 《Journal of Earth Science and Engineering》 2015年第6期372-381,共10页
Studying environmental phenomenon in Rub' Al-Khali (Arabic name of"Empty Quarter"), as one of the largest deserts in the world, requires adopting some advanced spatial technologies in conjunction with the data re... Studying environmental phenomenon in Rub' Al-Khali (Arabic name of"Empty Quarter"), as one of the largest deserts in the world, requires adopting some advanced spatial technologies in conjunction with the data recorded in the field in order to device better understanding. The paper utilizes the technologies of GIS (geographical information systems) and RS (remote sensing) in order to study large amount of weather data recorded in the field from different sources related to oil and gas industry in Rub' AI-Khali desert. The main objective is to identify the wind directions and its movement in Kidan areas and the areas south and east of Shaybah in Rub' Al-Khali desert. The study used different sources of data mainly recorded by the seismic campaigns' base camps and the drilling rig camps or the civil works camps. Wind Roses were created for all metrological weather stations in the study area. Also, the study tried to analyze the dune types using satellite imageries and identify the relation of its shapes to the wind direction. The final aim of the result of this study is to help in planning best locations to build facilities for new major oil and gas project. 展开更多
关键词 WIND OIL DIRECTIONS ROSES GIS
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Discussion on Application of 3S Technologies in Cadastral Surveying and Mapping
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作者 Yonghua ZHAO 《Agricultural Biotechnology》 CAS 2021年第3期97-100,共4页
In order to explore the application of 3S technologies in modern urban cadastral surveying and mapping,we analyzed the equipment composition of the global positioning system,the advantages of GPS surveying and mapping... In order to explore the application of 3S technologies in modern urban cadastral surveying and mapping,we analyzed the equipment composition of the global positioning system,the advantages of GPS surveying and mapping technology,and the main functions of RS and GIS technologies.GPS technology can improve the accuracy of boundary points of surveying and mapping areas,thereby improving the efficiency of surveying and mapping work and the accuracy of surveying and mapping information;remote sensing surveying and mapping technology has a large observation range and observation space,and RS technology can be used to collect data in remote mountainous areas to reduce the cost of manpower and material resources in surveying and mapping work;and GIS technology provides important data support for land planning and ownership definition.3S technologies optimize and streamline the surveying and mapping process with their own advantages,making the cadastral surveying and mapping work more scientific and efficient. 展开更多
关键词 Cadastral survey GPS RS GIS Control survey
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Analyzing and Modeling of Geo Spatial Effect on Radio Wave Propagation System Using Geospatial Technologies
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作者 Nigatu Bekele Biadgilgn Demissie 《Journal of Geographic Information System》 2017年第6期777-795,共19页
The research presented in this thesis reveals the level of rightness of the recurrence Prediction systems by correlated with geospatial effect. The Geospatial technology elements split up: Geographic Information Syste... The research presented in this thesis reveals the level of rightness of the recurrence Prediction systems by correlated with geospatial effect. The Geospatial technology elements split up: Geographic Information System (GIS), Remote Sensing (RS) and Global Positioning System (GPS) consolidated into this technique in light of the fact that the vast majority of the components in radio wave propagation are geographic highlights. In this exploration, ICEPAC remote arranging programming is tried in a field test completed in Tigray and Afar district. The consequence show that, the Prediction programming doesn’t put, day by day, regular and month to month topographical marvels into thought. Moreover, it doesn’t demonstrate the correct area of the radio stations. Furthermore, the new proposed ICEPAC Calibration algorithm anticipates a good Signal quality for frequencies in the vicinity of 1.5 MHz up to 30 MHz. The total result showed that Geographical Information Systems (GIS) are getting to be noticeably valuable apparatuses in accumulation, stockpiling, control and portrayal of Geo spatial information and also the RS and GIS situated Signal quality forecast can essentially enhance forecast quality contrasted with the hypothetical free space demonstration which does not consider any Geo spatial and neighborhood landscape highlights impacts. 展开更多
关键词 GIS REMOTE SENSING SIGNAL GPS GEOSPATIAL Data
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Geographic Information Technologies for the Study of Mass Wasting Hazards
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作者 Henry Pacheco Carlos Suárez 《International Journal of Geosciences》 2014年第5期519-526,共8页
The purpose of the research was to obtain the mass wasting hazard map for the state of Vargas, central coast of Venezuela, using GIS technology. The work was developed through the heuristic method with the generation ... The purpose of the research was to obtain the mass wasting hazard map for the state of Vargas, central coast of Venezuela, using GIS technology. The work was developed through the heuristic method with the generation of thematic digital maps, univariate statistical treatment, weighting of each variable and quantifying the relationship of each parameter unit regarding mass wasting processes. The algorithm designed to perform map algebra was designed using the variables: surface geology, slope, slope orientation, terrain curvature, moisture topographic index, power index surface flow rate and capacity sediment transport and the rate normalized difference vegetation. The results show a distribution of landslide hazard with the highest values in the west central part of Vargas state, where the dominant lithology is incompetent, and combined with topographic elements, determining high instability, meanwhile the lower hazard areas were found in specific areas such as the middle watershed areas east of the state. The calibration of this model shows a reliability of 80%, so it is highly advisable to use the information generated in this work by governmental and non-governmental organizations in the planning, management and use of land. 展开更多
关键词 MASS WASTING Hazards GIS Vargas STATE VENEZUELA
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Use of New Technologies for Solution of Environmental Problems in Azerbaijan
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作者 Garib Shamil ogli Mammadov 《Journal of Earth Science and Engineering》 2012年第6期360-365,共6页
Materials on the environmental impacts of natural cataclysm and their possible implications, as well as the types of natural disasters the most frequently encountered in recent years in Azerbaijan have been shown in t... Materials on the environmental impacts of natural cataclysm and their possible implications, as well as the types of natural disasters the most frequently encountered in recent years in Azerbaijan have been shown in the article. Some of them have been described in more details of solving the most common problems. In addressing these challenges, using advanced information technology plays a huge role. In this respect, the paper provides information about new technologies used in the country to protect the environment and about international projects involving a State Committee on land and cartography of Azerbaijan Republic. 展开更多
关键词 Natural cataclysm areas of ecological trouble GIS (geographic information system) orthophotoplan aerophoto andspace photography.
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Environmental Assessment and Analysis of Chemical Properties of Drinking Water Using Geo-Spatial Technologies: Examples from Lahore Metropolitan
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作者 Ali Imam Mirza Ali Iqtadar Mirza +14 位作者 Tabasam Jamal Syed Shehzad Hassan Muhammad A. Butt Atif Ali Hafsa Batool Rashid Mahmood Attia Naz Azam Sohail Imran Saddique Kaukab Sana Alvi Javed Ahmad Safeer Ali Muneeb Aamir Azeem Akhtar Arshad Javed 《Advances in Remote Sensing》 2018年第3期259-275,共17页
The contamination of drinking water in Pakistan is a serious threat to its citizens. Urbanization leads to an increased demand of drinking water supply that leads to excessive drawdown that further causes lowering of ... The contamination of drinking water in Pakistan is a serious threat to its citizens. Urbanization leads to an increased demand of drinking water supply that leads to excessive drawdown that further causes lowering of water table. The current WASA (Water and Sanitation Authority) supply network does not fulfill the demand of a growing metropolitan city of Lahore. The drawdown of Lahore is absolutely reliant on Water and Sanitation Authority (WASA) water supply network that causes numerous problems due to inappropriate management of groundwater capital and increased urbanization. This research investigates groundwater qualities: Alkalinity, Arsenic, Calcium, chloride, Total Hardness, Magnesium, Nitrate, pH and Total Dissolved solids using geographic information system (GIS). Residents of high concentrated towns, like Samnabad Town, Allama Iqbal Town, Gulberg, Data Ganj Bakhsh Town, Ravi Town and Wahga town witness cut-down of water supply mainly due to over burden on tube wells. Chemical properties of drinking water show that most of the parameters were within the allowable limits of WHO whereas the pH, and arsenic values are higher than the average. Arsenic is a carcinogenic element which causes cancer and is higher in the drinking water. Finally, this study identifies highly contaminated groundwater zones and makes it convenient to find actual pollutants. Therefore, plans are needed to protect the aquifer. 展开更多
关键词 Water Contamination URBANIZATION GEOGRAPHIC Information System (GIS) CHEMICAL Properties CARCINOGENIC Elements WHO WebGIS RS WASA DNA pH TDS
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Site Suitability Evaluation for Sustainable Distribution of Hospital Using Spatial Information Technologies and AHP: A Case Study of Upper Egypt, Aswan City
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作者 Asmaa H. Ahmed Hatem Mahmoud Abdel Monteleb M. Aly 《Journal of Geographic Information System》 2016年第5期578-594,共17页
Site selection for location of a hospital is one of the crucial policy-related decisions taken by the government. In upper Egypt, the cities suffer from a shortage and bad distribution of hospital site. The selection ... Site selection for location of a hospital is one of the crucial policy-related decisions taken by the government. In upper Egypt, the cities suffer from a shortage and bad distribution of hospital site. The selection of the appropriate hospital site requires consideration of multiple alternative solutions and evaluation factor. We develop a Multi-Criteria Decision Support System (MCDSS) process that combines Geographical Information System (GIS) analysis with Analytical Hierarchy Process (AHP) and use this process to determine the optimum site for a new hospital in the Aswan urban area. Based on actual conditions Aswan city, we used three main factors and seven sub-factors. The main factors are urban, environmental and economic factors. An application adopting AHP process was developed to calculate weights of every factor. Spatial analysis in GIS was used to overlay and generate factors maps and suitability evaluation map. All maps are classified from 1 (low suitable) to 5 (high suitable) using spatial information technologies. The candidate sites are divided by best, good and unsuitable hospital areas. Best hospital site represents optimal sites;good hospital site can be used as back-up candidate sites. The study was found that best area (S3) is about 30%, and most of these are located in the south part of the study area;good area (S2) is about 58%, and most of these are located in the central part of the study area;unsuitable area (S1) is about 12%, and most of these are located in the Eastern and Western parts of the study area. Finally, the study ends with an assessment of proposed sites. 展开更多
关键词 Site Suitability Evaluation Geographic Information System (GIS) MCDSS Hospital Sitting Spatial Analysis
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