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Adaptive time-space resource and waveform control for collocated MIMO radar with simultaneous multi-beam 被引量:4
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作者 CHENG Ting LI Xi +1 位作者 TAN Qianqian SU Yang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2022年第1期47-59,共13页
Collocated multiple input multiple output(MIMO)radar,which has agile multi-beam working mode,can offer enhanced multiple targets tracking(MTT)ability.In detail,it can illuminate different targets simultaneously with m... Collocated multiple input multiple output(MIMO)radar,which has agile multi-beam working mode,can offer enhanced multiple targets tracking(MTT)ability.In detail,it can illuminate different targets simultaneously with multi-beam or one wide beam among multi-beam,providing greater degree of freedom in system resource control.An adaptive time-space resource and waveform control optimization model for the collocated MIMO radar with simultaneous multi-beam is proposed in this paper.The aim of the proposed scheme is to improve the overall tracking accuracy and meanwhile minimize the resource consumption under the guarantee of effective targets detection.A resource and waveform control algorithm which integrates the genetic algorithm(GA)is proposed to solve the optimization problem.The optimal transmitting waveform parameters,system sampling period,sub-array number,binary radar tracking parameterχ_i(t_k),transmitting energy and multi-beam direction vector combination are chosen adaptively,where the first one realizes the waveform control and the latter five realize the timespace resource allocation.Simulation results demonstrate the effectiveness of the proposed control method. 展开更多
关键词 multiple targets tracking(MTT) collocated multiple input multiple output(MIMO)radar time-space resource allocation waveform control
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Adaptive resource management for multi-target tracking in co-located MIMO radar based on time-space joint allocation 被引量:2
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作者 SU Yang CHENG Ting +2 位作者 HE Zishu LI Xi LU Yanxi 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第5期916-927,共12页
Compared with the traditional phased array radar, the co-located multiple-input multiple-output(MIMO) radar is able to transmit orthogonal waveforms to form different illuminating modes, providing a larger freedom deg... Compared with the traditional phased array radar, the co-located multiple-input multiple-output(MIMO) radar is able to transmit orthogonal waveforms to form different illuminating modes, providing a larger freedom degree in radar resource management. In order to implement the effective resource management for the co-located MIMO radar in multi-target tracking,this paper proposes a resource management optimization model,where the system resource consumption and the tracking accuracy requirements are considered comprehensively. An adaptive resource management algorithm for the co-located MIMO radar is obtained based on the proposed model, where the sub-array number, sampling period, transmitting energy, beam direction and working mode are adaptively controlled to realize the time-space resource joint allocation. Simulation results demonstrate the superiority of the proposed algorithm. Furthermore, the co-located MIMO radar using the proposed algorithm can satisfy the predetermined tracking accuracy requirements with less comprehensive cost compared with the phased array radar. 展开更多
关键词 co-located multiple-input multiple-output(MIMO)radar adaptive resource management multi-target tracking sub-array division time-space joint allocation
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Current status and diversity of fish resources in the Pinglu Canal Century Project
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作者 LU Jia TANG Wei +3 位作者 WANG Li XU Shengxian ZHANG Peng YANG Shengfa 《水利水电技术(中英文)》 北大核心 2025年第4期131-144,共14页
[Objective]The channel straightening project of the Pinglu Canal has fragmented the river course,compromising the integrity of original river course and causing ecosystem patchiness.Understanding the current status of... [Objective]The channel straightening project of the Pinglu Canal has fragmented the river course,compromising the integrity of original river course and causing ecosystem patchiness.Understanding the current status of fish resources and the characteristics of their diversity is crucial for the ecological management of the Pinglu Canal.[Methods]During the spring and autumn in 2021 and 2022,a survey of fish resources and species diversity in the Pinglu Canal was conducted using multi-mesh gill nets.A total of 125 fish species were collected,belonging to 10 orders,34 families,and 89 genera.[Results]The result showed that the Pinglu Canal contained three nationally protected Class II species,two endemic species of the Qinjiang River,three anadromous/migratory species,and eight invasive species,accounting for 2.4%,1.6%,2.4%,and 6.4%of the total species,respectively.The fish community primarily consisted of mid-and bottom-dwelling,adhesive-egg-laying,and omnivorous species.The Shannon-Wiener,Simpson,Margalef,and Pielou indices of the fish community in the Pinglu Canal ranged from 2.347 to 2.757,0.081 to 0.151,3.493 to 4.382,and 0.812 to 0.892,respectively.These indices showed relatively uniform distribution across different river reaches.[Conclusion]The result indicate that the fish community structure in the Pinglu Canal is relatively uniform.The reach from the Yujiang River to the Shaping River shows higher stability,while other river reaches experience moderate or severe disturbances.This study provides supplementary baseline data on the fish community structure in the Pinglu Canal and explores the potential impact of inter-basin connectivity on fish resources,aiming to provide a scientific basis for habitat restoration assessments after the channel straightening project. 展开更多
关键词 Pinglu Canal Project inter-basin connectivity fish resources community structure BIODIVERSITY influencing factors
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Human resources allocation for aircraft maintenance with predefined sequence 被引量:2
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作者 Zhaodong Huang Wenbing Chang +2 位作者 Yiyong Xiao Yuchun Xu Rui Liu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第6期1008-1013,共6页
There are always large-scale items in the maintenances schedule of aircraft system, many of which have been fixed to be done in predefined sequences, which leads the workflow to be sys-tematically complex and makes th... There are always large-scale items in the maintenances schedule of aircraft system, many of which have been fixed to be done in predefined sequences, which leads the workflow to be sys-tematically complex and makes this kind of problem quite different from all sorts of existing job-selection modes. On the other hand, the human resources are always limited and men have different working capabilities on different items, which make the allocation operation of human resources be much roomy. However, the final total time span of maintenance is often required to be as short as possible in many practices, in order to suffer only the lowest cost of loss while the system is stopping. A new model for op-timizing the allocation if aircraft maintenance human resources with the constraint of predefined sequence is presented. The ge-netic algorithm is employed to find the optimal solution that holds the shortest total time span of maintenance. To generate the ul-timate maintenance work items and the human resource array, the sequences among all maintenance work items are considered firstly, the work item array is then generated through traversal with the constraint of maintenance sequence matrix, and the human resources are finally allocated according to the work item array with the constraint of the maintenance capability. An example is demonstrated to show that the model and algorithm behave a satisfying performance on finding the optimal solution as expected. 展开更多
关键词 aircraft maintenance human resources allocation predefined sequence genetic algorithm.
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Mineral Resources:Global Wealth or Warfare 被引量:1
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作者 Safi Ur Rehman 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期162-162,共1页
Uneven distribution of mineral resources has resulted in mineral-rich and mineral-poor countries. Regardless how much a country is endowed with mineral resources,they must be rationally,economically, and efficiently m... Uneven distribution of mineral resources has resulted in mineral-rich and mineral-poor countries. Regardless how much a country is endowed with mineral resources,they must be rationally,economically, and efficiently managed,protected,exploited, and used.It is the right of a country to take full control on its mineral resources and to promulgate policies and laws for mineral exploration,mining,and sustainable development.Mineral resources constitute an important basis of social and economic developpment of a country.The efficient and 展开更多
关键词 MINERAL resources MINING POLICY
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Crop Resources Ethic in Plant Genetic Engineering and Fortune Transfer Between Generations 被引量:1
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作者 WANG Xiaowei DING Guangzhou LIANG Xueqing 《Journal of Northeast Agricultural University(English Edition)》 CAS 2006年第2期169-173,共5页
The relation between human and crop resources belongs to the ethic of resources exploitation. The purposes of discussing the ethic of crop resources are to protect the ecology and safety of crops, to gain sustainable ... The relation between human and crop resources belongs to the ethic of resources exploitation. The purposes of discussing the ethic of crop resources are to protect the ecology and safety of crops, to gain sustainable development, furthermore, to choose and form the production structure that is favorable to saving crop resources and protecting the ecology of crops. Plant genetic engineering is the technology of molecule breeding of rearrangement of inheritance materials at the level of molecule directionally, of improving plant properties and of breeding high quality and yield varieties of crops. The prominent effects of the technology on the crop ecological system are human subjective factors increasing as well as violating the nature and intensifying the conflict between human being and nature. Therefore, in plant genetic engineering, crop resources exploitation should follow certain ethic principles. Under the theory of ethics of natural resources, by the means of biologinal-statistics, the author systematically analyzed the possible model of crop resources transfer between generations as well as the transfer mode of magnitude of real materials and magnitude of value. 展开更多
关键词 plant genetic engineering crop resources ETHIC fortune transfer between generations
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Protection and Quality Control of Wild Chinese Herbal Medicine Resources in Nature Reserves by Taking Longyuwan Scenic Spot Within Funiu Mountain Nature Reserve as an Example 被引量:1
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作者 Wang Shao-hui Liu Meng-na +4 位作者 Wang Xu Zhang Ya-chen Han Yi-wen Zhang Ce Liu Tong-xiang 《Journal of Northeast Agricultural University(English Edition)》 CAS 2016年第3期90-96,共7页
This paper discussed how to protect and control the quality of wild Chinese herbal medicine resources in nature reserves by taking Longyuwan National Forest Park within Funiu Mountain Nature Reserve as an example. Thr... This paper discussed how to protect and control the quality of wild Chinese herbal medicine resources in nature reserves by taking Longyuwan National Forest Park within Funiu Mountain Nature Reserve as an example. Through the combination of three methods including literature review, visiting and investigational studies, and field surveys, the data of investigation, collection and collation were analyzed. According to data of surveys, collection and collation, problems related to the protection of wild Chinese herbal medicine resources faced by Longyuwan Scenic Spot within Funiu Mountain Nature Reserve were also analyzed and protection strategies and quality control of wild Chinese herbal medicine resources in this nature reserve were discussed. It was expected that the results would provide important scientific references for the sustainable development, protection and quality control of wild Chinese herbal medicine resources within nature reserves. 展开更多
关键词 nature reserve wild Chinese herbal medicine resource PROTECTION quality control
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Resources—Towards Sustainable Use
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作者 Priscus Roamn Kaspana 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期154-154,共1页
A resource is any physical or virtual entity of limited availability used to earn good life.Resources are divided into natural and human resources.Natural resources are derived from the environment and are classified ... A resource is any physical or virtual entity of limited availability used to earn good life.Resources are divided into natural and human resources.Natural resources are derived from the environment and are classified on the basis of origin,including biotic resources like forests,animals and their products, marine organisms and minerals.Abiotic resources 展开更多
关键词 biotic ABIOTIC resources RENEWABLE non-renewable resources HUMAN resources
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Moving Resources to the People or Moving the People to the Resources? A Hypothetical Consideration for Addressing Sustainability
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作者 J.Murphy D.Perrone G.Hornberger 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期129-129,共1页
Water and energy are rarely linked politically or technologically,yet both resources are intimately dependant upon each other.Energy is consumed by the extraction,distribution,and treatment of water.Water is consumed ... Water and energy are rarely linked politically or technologically,yet both resources are intimately dependant upon each other.Energy is consumed by the extraction,distribution,and treatment of water.Water is consumed in the production and use of energy.Our study looks at this nexus,specifically,for resource islands—communities located considerable distances from their water and energy resources.Resource 展开更多
关键词 WATER ENERGY water-energy NEXUS resources resource island Tucson Arizona USA
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Human Resources Accounting
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作者 LIN Kai-xie (Financial Department of Youxi Tobacco Company, Sanming 365000, China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期228-,共1页
The 21 st century will be the epoch of knowled ge economy. Knowledge economy is to develop economy on the basis of knowledge will surely become the major resources of economy development. Therefore, human resources ac... The 21 st century will be the epoch of knowled ge economy. Knowledge economy is to develop economy on the basis of knowledge will surely become the major resources of economy development. Therefore, human resources accounting which provides such information as the ebb and follow of hu man resources investment, the size of the human resources employment, will bec ome the main stream of accounting the time of knowledge economy. To face China ’s reality, to develop economy, and to flourish enterprises, we must combine it with our country’s reality. Study and improve our accounting theories of human r esources, embody the essential contents of stressing knowledge, respecting perso nnel in the design of our present system, and stimulate fundamentally motivation of the work force. 展开更多
关键词 knowledge economy human resources human resourc es accounting
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Multi-objective planning model for simultaneous reconfiguration of power distribution network and allocation of renewable energy resources and capacitors with considering uncertainties 被引量:9
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作者 Sajad Najafi Ravadanegh Mohammad Reza Jannati Oskuee Masoumeh Karimi 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第8期1837-1849,共13页
This research develops a comprehensive method to solve a combinatorial problem consisting of distribution system reconfiguration, capacitor allocation, and renewable energy resources sizing and siting simultaneously a... This research develops a comprehensive method to solve a combinatorial problem consisting of distribution system reconfiguration, capacitor allocation, and renewable energy resources sizing and siting simultaneously and to improve power system's accountability and system performance parameters. Due to finding solution which is closer to realistic characteristics, load forecasting, market price errors and the uncertainties related to the variable output power of wind based DG units are put in consideration. This work employs NSGA-II accompanied by the fuzzy set theory to solve the aforementioned multi-objective problem. The proposed scheme finally leads to a solution with a minimum voltage deviation, a maximum voltage stability, lower amount of pollutant and lower cost. The cost includes the installation costs of new equipment, reconfiguration costs, power loss cost, reliability cost, cost of energy purchased from power market, upgrade costs of lines and operation and maintenance costs of DGs. Therefore, the proposed methodology improves power quality, reliability and security in lower costs besides its preserve, with the operational indices of power distribution networks in acceptable level. To validate the proposed methodology's usefulness, it was applied on the IEEE 33-bus distribution system then the outcomes were compared with initial configuration. 展开更多
关键词 optimal reconfiguration renewable energy resources sitting and sizing capacitor allocation electric distribution system uncertainty modeling scenario based-stochastic programming multi-objective genetic algorithm
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Woody Plants as Resources in China, Their Conservation and Use
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作者 Ren Xianwei Liang Hongping Zhang YujunForest Resources College. Beijing Forestry University 《北京林业大学学报》 CAS CSCD 北大核心 1992年第S2期80-89,共10页
This paper deals with species of the woody plants in China and their conservation problems. The floristic elements of woody plants was computed and the results indicate that the elements of Tropical Asia accounts for ... This paper deals with species of the woody plants in China and their conservation problems. The floristic elements of woody plants was computed and the results indicate that the elements of Tropical Asia accounts for the largest number of genus while the proportion of the elements of Temperate Asia is relatively small. For each of eight vegetation region, the number of woody plants was established and a list of the endangered and rare species was compiled. In regard to the problems of protecting the endangered precious and rare species at present we propose some workable solutions. 展开更多
关键词 WOODY PLANTS resources CONSERVATION USE
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Study of Chinese Sustainable Developing Project for Energy Resources
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作者 Kuangming Zhang,Wenhui Huang,Huajun Wang 1.School of Energy Resources,China University of Geosciences(Beijing),Beijing 100083,China. 2.Key Laboratory of Marine Reservoir Evolution and Hydrocarbon Accumulation Mechanism,Ministry of Education,China University of Geosciences(Beijing),Beijing 100083,China 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期146-147,共2页
Since the last half century,the world has been being in theme of peace and development,and passed through another glorious period with the rapid development of the economy,science and technology. In the energy field o... Since the last half century,the world has been being in theme of peace and development,and passed through another glorious period with the rapid development of the economy,science and technology. In the energy field of the globe,as the fuel with superior quality,the petroleum and gas gradually replaced the coal of the leading role in energy resources’ consumption,after the mineral energy replaced firewood.Moreover,various types of new energy are beginning to get application。 展开更多
关键词 energy resources CONSUMPTION ECONOMY environment SUSTAINABLE development
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The Human Dimension in the UNESCO Kogelberg Biosphere Reserve:Integrating Livelihood Issues of Small-Scale Fisheries with the Conservation of Natural Resources
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作者 Inka Schomer 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期86-86,共1页
Fisheries management worldwide struggles to strike a balance between protecting resources,ensuring fair access to resources and promoting economic effectiveness and stability.The transition to a participatory democrac... Fisheries management worldwide struggles to strike a balance between protecting resources,ensuring fair access to resources and promoting economic effectiveness and stability.The transition to a participatory democracy in South Africa in 1994 resulted in the transformation of government institutions and an extensive process of legislative reform regarding 展开更多
关键词 CONSERVATION SMALL-SCALE FISHERIES marine resources LIVELIHOOD strategies
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Tectonics and Natural Resources of Pakistan
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作者 Arshad Ali 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期56-57,共2页
Pakistan has fascinating geology.It exposes Ophiolites in the north and west and sedimentary strata in the south.It preserves lithological and tectonic features of ancient island arc type Himalayan orogeny in the nort... Pakistan has fascinating geology.It exposes Ophiolites in the north and west and sedimentary strata in the south.It preserves lithological and tectonic features of ancient island arc type Himalayan orogeny in the north and Andean type active orogeny in the south.The Main Karakrum Thrust,Kohistan -Ladakh Island arc,Main Mantle Thrust,Main Boundary Thrust and Main Frontal Thrust are 展开更多
关键词 TECTONICS of Pakistan MINERAL resources INDIAN Eurasian PLATES COLLISION
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Characteristics,Current Status and Strategy on Exploitation of Agricultural Natural Resources in China
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作者 ZHANG Yan 《Journal of Northeast Agricultural University(English Edition)》 CAS 2010年第3期82-87,共6页
This paper formulated the present characteristics, current status and the problems of agricultural natural China. Measures of preservation and strategy about exploitation of agricultural natural resources were put for... This paper formulated the present characteristics, current status and the problems of agricultural natural China. Measures of preservation and strategy about exploitation of agricultural natural resources were put forward, provide a scientific basis for the government to make policies . 展开更多
关键词 AGRICULTURE natural resource strategy of exploitation resources in which would
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3D Modeling Quantitative Evaluation for the Underground Space Resources in Beijing City
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作者 Yi Tian,Jianping Chen,Limei Wang School of Land Resources and Technology,China University of Geosciences(Beijing),Beijing 100083,China. 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期283-284,共2页
Recently,underground space evaluation has become fundamental for a city’s long term sustainable development planning.This paper,based on the 3D-GIS tools,adopts"multi-factors comprehensive evaluation"models... Recently,underground space evaluation has become fundamental for a city’s long term sustainable development planning.This paper,based on the 3D-GIS tools,adopts"multi-factors comprehensive evaluation"models to establish a practicable underground space resources quantitative evaluation system.It sets up 展开更多
关键词 CITY UNDERGROUND SPACE resources QUANTITATIVE evaluation 3D MODELING
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Geothermal Resources Potential Analyses of Tanggu Urban Area and the Vicinity,Tianjin
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作者 Yongjiang Yang,Jiulong Liu,Baozhen Jin,Fei Liu Tianjin Geothermal Exploration and Development-Designing Institute,Tianjin 300250,China. 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期9-10,共2页
In order to construct a newly developed green area, the Tanggu urban area as the core part of Binhai new area,needs more and more clean energy year by year. This area is abound in geothermal resources endowed by the g... In order to construct a newly developed green area, the Tanggu urban area as the core part of Binhai new area,needs more and more clean energy year by year. This area is abound in geothermal resources endowed by the grand Nature.Based on the estimation of 展开更多
关键词 Dongying Formation GEOTHERMAL resources potential development COUNTERMEASURE Tanggu urban area and VICINITY of TIANJIN
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Interspecific Chromosome Substitution Lines as Genetic Resources for Improvement,Trait Analysis and Genomic Inference 被引量:1
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作者 RASKA Dwaine A SAHA Sukumar JENKINS Johnie N MCCARTY Jack C STELLY David M 《棉花学报》 CSCD 北大核心 2008年第S1期84-,共1页
The genetic base that cotton breeders commonly use to improve Upland cultivars is very narrow.The AD-genome species Gossypium barbadense,G.tomentosum,and G.mustelinum are part of
关键词 CS Interspecific Chromosome Substitution Lines as Genetic resources for Improvement Trait Analysis and Genomic Inference
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Interlinkage Between Global Environmental Changes,Water Resources Availability and Quality in the East African Rift:Preliminary Analyses and Some Cases:The MaWARi Project(Kenya,Ethiopia,Djibouti,France)
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作者 Kebede Seifu 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期36-37,共2页
The East African Rift extending across Djibouti, Ethiopia and Kenya is characterized by low level of economic development,high level of poverty,increasing population,scarce natural resources(land,water, and environmen... The East African Rift extending across Djibouti, Ethiopia and Kenya is characterized by low level of economic development,high level of poverty,increasing population,scarce natural resources(land,water, and environment),complex and rich ecosystems, increasing desertification and degrading biodiversity, underdeveloped regional trade and market,water resources mainly stored in groundwater and 展开更多
关键词 East AFRICAN RIFT groundwater resources water AVAILABILITY global environmental change impacts SCIENTIFIC regional cooperation
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