期刊文献+
共找到834篇文章
< 1 2 42 >
每页显示 20 50 100
Carrying Capacity and Coupling Coordination of Water and Land Resources Systems in Arid and Semi-arid Areas: A Case Study of Yulin City, China
1
作者 ZHANG Qianxi CAO Zhi +1 位作者 WANG Yongsheng HUANG Yijia 《Chinese Geographical Science》 SCIE CSCD 2024年第5期931-950,共20页
Quantitatively assessing the carrying capacity of water and land resources systems in arid and semi-arid areas is crucial for achieving the 2030 Sustainable Development Goals.In this work,taking Yulin City in China as... Quantitatively assessing the carrying capacity of water and land resources systems in arid and semi-arid areas is crucial for achieving the 2030 Sustainable Development Goals.In this work,taking Yulin City in China as a case study and employing the Criteria Importance Through Intercriteria Correlation(CRITIC)method,a modified model of coupling degree was developed to evaluate the car-rying capacity of water and land resources systems endowment and utilization,as well as their coupling coordination degree from 2013 to 2020.Our findings indicate that the water and land resources of Yulin are diminishing due to declines in agriculture,higher industrial water use,and wetland shrinkage.However,reallocating domestic water for ecological sustainability and reducing sloping farmland can mitigate this trend of decline.Temporally,as the coupling coordination between water and land resources system endowment in Yulin continuously improved,the coupling coordination between water and land resources system utilization first decreased and then in-creased with 2016 as the turning point.Spatially,the carrying capacity of water and land resources systems,the coupling coordination degree between water and land resources system endowment,and the coupling coordination degree between water and land resources system utilization in Yulin exhibited the same pattern of being higher in the six northern counties than in the six southern counties.Improving the water resources endowment is vital for the highly efficient use of water and land resources. 展开更多
关键词 water and land resources systems carrying capacity coupling coordination human-earth system sustainable development Yulin City China
下载PDF
Integration system research and development for three-dimensional laser scanning information visualization in goaf 被引量:1
2
作者 罗周全 黄俊杰 +2 位作者 罗贞焱 汪伟 秦亚光 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第7期1985-1994,共10页
An integration processing system of three-dimensional laser scanning information visualization in goaf was developed. It is provided with multiple functions, such as laser scanning information management for goaf, clo... An integration processing system of three-dimensional laser scanning information visualization in goaf was developed. It is provided with multiple functions, such as laser scanning information management for goaf, cloud data de-noising optimization, construction, display and operation of three-dimensional model, model editing, profile generation, calculation of goaf volume and roof area, Boolean calculation among models and interaction with the third party soft ware. Concerning this system with a concise interface, plentiful data input/output interfaces, it is featured with high integration, simple and convenient operations of applications. According to practice, in addition to being well-adapted, this system is favorably reliable and stable. 展开更多
关键词 GOAF laser scanning visualization integration system 1 Introduction The goaf formed through underground mining of mineral resources is one of the main disaster sources threatening mine safety production [1 2]. Effective implementation of goaf detection and accurate acquisition of its spatial characteristics including the three-dimensional morphology the spatial position as well as the actual boundary and volume are important basis to analyze predict and control disasters caused by goaf. In recent years three-dimensional laser scanning technology has been effectively applied in goaf detection [3 4]. Large quantities of point cloud data that are acquired for goaf by means of the three-dimensional laser scanning system are processed relying on relevant engineering software to generate a three-dimensional model for goaf. Then a general modeling analysis and processing instrument are introduced to perform subsequent three-dimensional analysis and calculation [5 6]. Moreover related development is also carried out in fields such as three-dimensional detection and visualization of hazardous goaf detection and analysis of unstable failures in goaf extraction boundary acquisition in stope visualized computation of damage index aided design for pillar recovery and three-dimensional detection
下载PDF
System dynamics model of Suzhou water resources carrying capacity and its application 被引量:14
3
作者 Li CHENG 《Water Science and Engineering》 EI CAS 2010年第2期144-155,共12页
A model of Suzhou water resources carrying capacity (WRCC) was set up using the method of system dynamics (SD). In the model, three different water resources utilization programs were adopted: (1) continuity of... A model of Suzhou water resources carrying capacity (WRCC) was set up using the method of system dynamics (SD). In the model, three different water resources utilization programs were adopted: (1) continuity of existing water utilization, (2) water conservation/saving, and (3) water exploitation. The dynamic variation of the Suzhou WRCC was simulated with the supply-decided principle for the time period of 2001 to 2030, and the results were characterized based on socio-economic factors. The corresponding Suzhou WRCC values for several target years were calculated by the model. Based on these results, proper ways to improve the Suzhou WRCC are proposed. The model also produced an optimized plan, which can provide a scientific basis for the sustainable utilization of Suzhou water resources and for the coordinated development of the society, economy, and water resources. 展开更多
关键词 system dynamics (SD) water resources carrying capacity (WRCC) eco-environmental water demand Suzhou City
下载PDF
Mission-oriented dynamic optimization model of carrying spares for warship redundant system 被引量:5
4
作者 RUAN Minzhi LI Hua WANG Junlong 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第3期539-548,共10页
Redundancy is a common structure for warship system,and it is an effective way to improve the reliability of the system.In this paper, warship system is taken as the object of study,based on the system reliability equ... Redundancy is a common structure for warship system,and it is an effective way to improve the reliability of the system.In this paper, warship system is taken as the object of study,based on the system reliability equivalence principle, a spares demand rate calculation method for redundant system is proposed through structure transformation. According to the system analysis method, the general modeling data structure of spares support echelon and system indenture is established, and the mission success probability is taken as the optimization target to build the dynamic optimization model of carrying spares during the process of multi-phase. By introducing the Lagrange multiplier, the spares weight, volume and cost are transformed to the single target of the spares total scale, and the initial Lagrange factors and its dynamic adjustment policy is proposed. In a given example, the main influence factors of the carrying spares project are analyzed, and the study results are in accordance with the reality, which can provide a new approach to mission-oriented carrying spares optimization for the redundant system. 展开更多
关键词 REDUNDANCY reliability equivalence WARSHIP carrying spares OPTIMIZATION
下载PDF
Spatiotemporal patterns of the forage-livestock balance in the Xilin Gol steppe,China:implications for sustainably utilizing grassland-ecosystem services 被引量:3
5
作者 QU Yingbo ZHAO Yuanyuan +2 位作者 DING Guodong CHI Wenfeng GAO Guanglei 《Journal of Arid Land》 SCIE CSCD 2021年第2期135-151,共17页
Understanding the spatiotemporal patterns of the forage-livestock balance is imperative for regionally arranging animal husbandry production while ensuring sustainable grassland-ecosystem service use.The Xilin Gol ste... Understanding the spatiotemporal patterns of the forage-livestock balance is imperative for regionally arranging animal husbandry production while ensuring sustainable grassland-ecosystem service use.The Xilin Gol steppe is an important native grassland resource in Inner Mongolia Autonomous Region,China.This study aimed to elucidate the dynamics of the forage-livestock balance in the Xilin Gol steppe during the period 2000–2015.We evaluated the forage production and corresponding livestock carrying capacity(LCC)in the growing seasons of 2000–2015 using remote sensing data and field surveys.The spatiotemporal patterns of the forage-livestock balance were then assessed at regional,city(including city,county and banner),and village scales using statistical and household survey data.The results showed that both forage production and LCC decreased in the Xilin Gol steppe from east to west.During the period 2000–2015,the regional average forage production and corresponding LCC fluctuated without following a distinct trend,but were consistent with the variations in precipitation.The forage-livestock balance varied with time,space,and scale.At the regional scale,steppes were overgrazed in the early 2000s,but a forage-livestock balance or even grazing potential was achieved in other years.At the city scale,approximately half of the region exhibited a"forage-livestock balance"since 2000.However,about half of the region still experienced overgrazing,which mainly located in the southwest sandy zones.Such changes may have been affected by the variations in grassland quality,forage production,compensation payment,and so on.We suggest a location-specific management scheme for grazing constraints,ecological compensation payment,and industry development to aid in harmonizing animal husbandry and environmental restoration,while promoting sustainable development goals by 2030. 展开更多
关键词 forage production livestock carrying capacity forage-livestock balance Xilin Gol steppe sustainable development
下载PDF
Assessing the Carrying Capacity of Tourist Resorts: An Application of Tourists’ Spatial Behavior Simulator Based on GIS and Multi-Agent System 被引量:2
6
作者 ZHANG Ren-jun 1,2 1. Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, Sichuan, China 2. Graduated School of the Chinese Academy of Sciences, Beijing 100039, China 《Wuhan University Journal of Natural Sciences》 EI CAS 2005年第4期779-784,共6页
Based on the study of visitors' individual spatial behaviors, a tourists'spatial behavior simulator (TSBS) to assess the carrying capacity of tourist resorts was developed,TSBS employs GIS (Geographic Informat... Based on the study of visitors' individual spatial behaviors, a tourists'spatial behavior simulator (TSBS) to assess the carrying capacity of tourist resorts was developed,TSBS employs GIS (Geographic Information System) to manage the spatial data,and Multi-Agent systemto simulate the actions of individual visitors. By utilizing TSBS, visitors' travel patterns such aslocation, cost, and state can be analyzed and predicted. Based on this analysis and prediction, themodel of assessing the carrying capacity of resorts is built. Our results show that TSBS will be aneffective tool to accurately assess the carrying capacity of tourist resorts. 展开更多
关键词 tourist resort carrying capacity TSBS GIS MULTI-AGENT SIMULATOR
下载PDF
Construction of Evaluation Index System of Tourism Carrying Capacity of the Jokhang Temple Scenic Spot 被引量:4
7
作者 WANG Zhongbin 《Journal of Landscape Research》 2018年第1期90-96,共7页
Based on the in-depth study on the theory of tourism carrying capacity at home and abroad, author of this paper defined the concept and connotation of tourism carrying capacity, and proposed the evaluation index syste... Based on the in-depth study on the theory of tourism carrying capacity at home and abroad, author of this paper defined the concept and connotation of tourism carrying capacity, and proposed the evaluation index system of tourism carrying capacity. He also conducted a systematic analysis of tourism resources in the Jokhang Temple scenic spot, constructed an evaluation index system of tourism carrying capacity of the Jokhang Temple scenic spot, pointed out the status quo of its carrying capacity and factors constraining the carrying capacity through quantitative calculation, and put forward suggestions to regulate its carrying capacity. 展开更多
关键词 Carrying capacity of scenic spots EVALUATION Index system RESEARCH
下载PDF
Empirical Research on Carrying Capacity of Human Settlement System in Dalian City, Liaoning Province, China 被引量:12
8
作者 ZHENG Defeng ZHANG Yu +1 位作者 ZANG Zheng SUN Caizhi 《Chinese Geographical Science》 SCIE CSCD 2015年第2期237-249,共13页
Using the theories of population carrying capacity and ecological elasticity in other fields for reference, the connotation of regional human settlement system was defined from the viewpoint of the complex relationshi... Using the theories of population carrying capacity and ecological elasticity in other fields for reference, the connotation of regional human settlement system was defined from the viewpoint of the complex relationship among the factors such as regional population, resources, environment and economic and social development in the context of China′s rapid urbanization. Then the concept and characterization methods of the regional human settlement carrying capacity were proposed by means of population scale. Furthermore, a model of carrying capacity-pressure-state-response(CPSR) on regional human settlement system was established by referencing pressure-state-response(PSR) model, and the Catastrophe Theory was introduced to determine the corresponding standards of multi-criteria programming and evaluation. Taking Dalian City, Liaoning Province, China as an example, an empirical analysis on evaluation of human settlement system from 2000 to 2012 was carried out. The results showed that the carrying capacity of human settlement system in Dalian was fluctuating between 9.6 × 106 to 10 × 106 persons with a quantitative stage of the dynamic regulation. During the research period the load index of human settlement system in Dalian dropped from 0.96 to 0.84 with a lower pressure of human settlement system than the national average level. And the emergency response grades of human settlement system in Dalian were kept in grade Ⅱ(orange warning) or grade Ⅲ(yellow warning). Human settlement system of Dalian was in slight security state as a whole, but the load had a tendency of increase in recent years. The related departments should pay close attention to regional human settlement system and take active measures to improve human settlement by both intensity control and total quantity control. By comparison, analysis and discussion, it was considered that the results were basically accordded with the current situations of human settlement in Dalian, and the evaluation results were more reliable, visualized and easily applied in practice. Therefore, the above-mentioned concepts, characterization and evaluation methods of the regional human settlement system and carrying capacity could provide a new thought and method for quantitative evaluation of human settlement. 展开更多
关键词 human settlement capacity-pressure-state-response(CPSR) model carrying capacity multi-objective decision making Dalian City China
下载PDF
A model to assess fundamental and realized carrying capacities of island ecosystem:A case study in the southern Miaodao Archipelago of China 被引量:4
9
作者 SHI Honghua SHEN Chengcheng +7 位作者 ZHENG Wei LI Fen WANG Xiaoli CHI Yuan GUO Zhen QIAO Mingyang GAO Liyuan DING Dewen 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2016年第2期56-67,共12页
Research on carrying capacity, aiming at maintaining the limited ability of the Earth's life supporting system to sustain human development, requires a comprehensive and ecosystem-based approach to monitor and assess... Research on carrying capacity, aiming at maintaining the limited ability of the Earth's life supporting system to sustain human development, requires a comprehensive and ecosystem-based approach to monitor and assess the localized sustainability of coupled social and ecological systems. A definition termed the ecosystem-based carrying capacity of island(EBCCI) was developed in this paper of which the indices of fundamental and realized carrying capacities of island(FCCI and RCCI) were highlighted to emphasize the inter-dependencies between social systems and ecological systems. In order to avoid the difficulties and uncertainties of direct assessment, the related assessment model was established on the basis of synthetic evaluation of inherent and external factors affecting the EBCCI. The southern Miaodao Archipelago(SMA) located in the intersection of the Bohai Sea and the Yellow Sea, China, was taken as a typical example to acquire integrated recognition of the island ecosystem and its carrying capacity so as to discuss its sustainable development. The index scores of FCCI and RCCI in the SMA were 0.818 5 and 0.712 9 out of 1.0, respectively, with acceptable uncertainties. The results showed a relatively well capacity to sustain progress and relatively well realization of the carrying capacity of island ecosystem, owing to a well capacity of ecologically regulating, general performance of both ecologically supporting and resource provisioning, and a relatively high level of social supporting system. The study implied that it was critical to optimize the inter-dependencies and to sustain the relative balance between social systems and ecological systems so as to improve the RCCI and further facilitate the sustainability of SMA. The approach proposed in this paper provides a powerful tool which is well applicative to the regional level of an oceanic island or archipelago to study the sustainable development and can be further popularized to the coastal zone. 展开更多
关键词 carrying capacity regional sustainability island ecosystem Miaodao Archipelago Bohai Sea
下载PDF
Spatio-temporal Pattern of Ecosystem Pressure in Countries Along the Belt and Road: Combining Remote Sensing Data and Statistical Data 被引量:1
10
作者 DU Wenpeng YAN Huimin +2 位作者 FENG Zhiming ZHANG Chao YANG Yanzhao 《Chinese Geographical Science》 SCIE CSCD 2022年第5期745-758,共14页
Building a Green Silk Road by integrating the Sustainable Development Goals(SDGs) is one of the Belt and Road Initiative(BRI) visions, but the BRI faces enormous challenge that is the conflict between economic develop... Building a Green Silk Road by integrating the Sustainable Development Goals(SDGs) is one of the Belt and Road Initiative(BRI) visions, but the BRI faces enormous challenge that is the conflict between economic development and ecological sustainability.Understanding the current scale and trend of the impact of human activities on the ecosystem is the preliminary work to ensure that human activities do not exceed the ecological carrying capacity under the BRI. This study evaluated the ecosystem pressure in countries along the Belt and Road(B&R) from 2000–2017 based on the supply-consumption balance relationship of ecological resources. Net primary productivity(NPP) is taken as the measure of ecological resources, and the supply level and consumption intensity of ecological resources is estimated based on remote sensing data and statistical data, respectively. Results show that thirteen countries with overconsumed ecological resources concentrated in the West Asia/Middle East. Although the intensity of the ecological resource consumption correlated with ecological resource endowments, the ecosystem pressure was determined by social development dependence on the ecological resources at the same ecological resource endowments level. Nearly 80% of countries along the B&R suffered from significantly increased(P < 0.05) ecosystem pressure during 2000–2017, since most of the countries along the B&R were developing countries,and their economic development was highly dependent on ecological resources. Some West Asia/Middle East countries successfully mitigated the ecosystem pressure by importing feed for livestock. Likewise, the Southeast Asian islands benefitted from the import of agricultural products. The results highlight that the BRI should reduce the dependence of social development demands on local ecological resources by international trade for ensuring the increasing ecosystem pressure trend within the ecological carrying capacity. 展开更多
关键词 Green Silk Road ecosystem pressure net primary productivity(NPP) ecological carrying capacity remote sensing
下载PDF
Spatial and Dynamic Analysis of Regional Sustainable Development Using Geographic Information System and Relative Carrying Capacity of Resources 被引量:3
11
作者 Qi Wang Xiaodan Wang +3 位作者 Hua Tang Jun Li Haihu Ma Tianxing Cheng 《Natural Resources》 2011年第1期28-34,共7页
Relative carrying capacity of resources is an index to measure sustainable development through carrying capacity. Case studies of eleven cities in Zhejiang (Hangzhou, Ningbo, Wenzhou, Jiaxing, Huzhou, Shaoxing, Jinhua... Relative carrying capacity of resources is an index to measure sustainable development through carrying capacity. Case studies of eleven cities in Zhejiang (Hangzhou, Ningbo, Wenzhou, Jiaxing, Huzhou, Shaoxing, Jinhua, Quzhou, Zhoushan, Taizhou and Lishui) illustrated regional sustainable development approach. In this study, to provide insight into spatial and dynamic analysis of region sustainable development, we calculated the relative carrying capacity of land resources and economical resources and synthetical carrying capacity of resources in different cities in Zhejiang, and geographic information system was carried out. The results showed that all cities but Hangzhou and Ningbo were ecologically sustainable, and relative carrying capacity of land resources in northern and eastern Zhejiang was larger than those in southern and western Zhejiang. The sampling years of Wenzhou, Hangzhou and Ningbo contribution rates of land resource to synthetic carrying capacity were grouped into three stages, and there were two milestones trends and changes in 1996 and 2004, respectively. This study demonstrated that geographic information system and relative carrying capacity of resources are effective for assessment of region sustainable development, and provide policy guidelines for decision-making. 展开更多
关键词 GEOGRAPHIC Information system Arcgis RELATIVE Carrying Capacity of RESOURCES REGIONAL SUSTAINABLE Development CONTRIBUTION Rate
下载PDF
THE CONSTRUCTION OF AN EBV-xy1E SHUTTLE VECTOR SYSTEM FOR THE STUDY OF MUTATI0N IN MAMMALIAN CELLS
12
《癌变.畸变.突变》 CAS CSCD 1991年第S1期86-86,共1页
The Pseudomonas putida TOL plasmid gene xy1E,whichproduces catechol 2,3-dioxygenase (CatO<sub>2</sub>ase;catechol:oxygen 2,3-oxidoreductase (decyclizing),EC 1.13.11.2 )was used as a target gene to stud... The Pseudomonas putida TOL plasmid gene xy1E,whichproduces catechol 2,3-dioxygenase (CatO<sub>2</sub>ase;catechol:oxygen 2,3-oxidoreductase (decyclizing),EC 1.13.11.2 )was used as a target gene to study the mechanisms ofmutation and induced mutation frequency in 展开更多
关键词 CATECHOL DIOXYGENASE OXIDOREDUCTASE SHUTTLE PLASMID mutation spraying carrying sence passages
下载PDF
Quantitative Evaluation on Urban Ecosystem Carrying Capacity in Tianjin Binhai New Area
13
作者 Li Xingfu Xu He 《Chinese Journal of Population,Resources and Environment》 2009年第4期64-68,共5页
Based on the concept of ecosystem carrying capacity,the indicator system of quantitative assessment was set up,which consisted of support indicator system and pressure indicator system.And the factor analysis method w... Based on the concept of ecosystem carrying capacity,the indicator system of quantitative assessment was set up,which consisted of support indicator system and pressure indicator system.And the factor analysis method was used to screen the indicator system.Different from the traditional indicator weight determination based on the absolute values of the coefficients of regression equation,the squares of factor loadings in the rotated component matrix were attempted to determine the weights of 40 assessment indicators.The result shows that ecological support system and pressure system in Binhai New Area are relatively balanced among six years,and the developing level of urban ecosystem is basically healthy on the whole.However,due to continuously increasing pressure of the resources consumption caused by the rapid growth of the second industry,which is the Leading Industry of Binhai New Area,the ecosystem carrying capacity reached the minimum in 2005. 展开更多
关键词 ecosystem carrying capacity factor analysis Binhai New Area
下载PDF
Research on the Evaluation System for Rural Public Safety Planning
14
作者 Ming SUN Jianxin YAN 《Asian Agricultural Research》 2014年第4期63-66,共4页
The indicator evaluation system is introduced to the study of rural public safety planning in this article.By researching the current rural public safety planning and environmental carrying capacity,we select some car... The indicator evaluation system is introduced to the study of rural public safety planning in this article.By researching the current rural public safety planning and environmental carrying capacity,we select some carrying capacity indicators influencing the rural public safety,such as land,population,ecological environment,water resources,infrastructure,economy and society,to establish the environmental carrying capacity indicator system.We standardize the indicators,use gray correlation analysis method to determine the weight of indicators,and make DEA evaluation of the indicator system,to obtain the evaluation results as the basis for decision making in rural safety planning,and provide scientific and quantified technical support for rural public safety planning. 展开更多
关键词 RURAL SAFETY PLANNING ENVIRONMENTAL carrying capac
下载PDF
Application of System Dynamics in Analyzing the Cultivated Land-Water Resources Carrying Capacity in Bijie Prefecture,China
15
作者 何仁伟 刘邵权 +2 位作者 李立娜 梁岚 李婷婷 《Journal of Donghua University(English Edition)》 EI CAS 2013年第3期228-238,共11页
The cultivated land-water resources carrying capacity (CL-WRCC) with the method of system dynamics (SD) were analyzed. Bijie prefecture of Guizhou province served as a case in this study. Bijie prefecture is one o... The cultivated land-water resources carrying capacity (CL-WRCC) with the method of system dynamics (SD) were analyzed. Bijie prefecture of Guizhou province served as a case in this study. Bijie prefecture is one of the least-developed areas in China. In Bijie, the physical and chemical characteristics of karst as well as the rapid economic development lead to the scarcities of cultivated land-water resources (CL-WR). On the basis of analysis on the subsystems of Bijie CL.WRCC system, the fundamental feedback structure of CL-WRCC was presented by causal loop diagram. Considering the three alms (" poverty alleviation and development, ecological construction, and population control") of Bijie as the major goals, Bijie CL-WRCC SD model was developed. Three scenarios, resource-saving and environment-friendly development-oriented scenario (Scenario 1 ), fast economic development-oriented scenario ( Scenario 2 ), and coordinated development-oriented scenario (Scenario 3 ), were investigated. Simulation results indicate that Scenario 3 which takes social economic development, environment protection, and cultivated land- water resources utilization into account, is the best alternative scenario. It can promote the coordination development of society, economy, cultivated land, water resources, and environment. In this study, the technological support and the decision-making for the rational use of CL-WR are provided not only in Bijie, but also in other similar regions of China. 展开更多
关键词 cultivated land-water resources CL-WR carrying capacity system dynamics SIMULATION Bijie prefecture
下载PDF
Foreign-oriented Hengshui Carries out Opening Policy
16
作者 Zhai Jichang,Mayor of Hengshui City,Hebei Province 《China's Foreign Trade》 1995年第9期35-35,共1页
Since ushering in the 1990s, Hengshui City has been taking advantage of its excellent geographical position to develop its foreign-oriented economy, with good results. Take last year for example, the city signed contr... Since ushering in the 1990s, Hengshui City has been taking advantage of its excellent geographical position to develop its foreign-oriented economy, with good results. Take last year for example, the city signed contracts for altogether 28 foreign-invested projects, with a total capital of US$19.37 million and contractual capital of US$ 5.73 million, 14 completed and constructing foreign-invested projects, of which six have been put into operation. The infrastructure is being further improved in the Hi-tech Industrial Park which includes 49 projects of a total investment of RMB 180 million. The Hengshui Lake Economic and Technology 展开更多
关键词 Foreign-oriented Hengshui carries out Opening Policy LAKE US
下载PDF
VIGOROUSLY CARRYING OUT FOREIGN TRADE AGENCY SYSTEM
17
《China's Foreign Trade》 1996年第10期7-9,6,共4页
Voices are growing louder and louder,calling for vigorously carryingout the foreign trade agency system in China’s foreign economic andtrade field.Vice Premier Li Lanqing in charge of foreign trade andeconomic cooper... Voices are growing louder and louder,calling for vigorously carryingout the foreign trade agency system in China’s foreign economic andtrade field.Vice Premier Li Lanqing in charge of foreign trade andeconomic cooperation has pointed out many times recently that theoperational mode of foreign trade should be transferred from thetraditional purchase system to service-type agency system.This isimportant to deepening the reform of the foreign trade system. 展开更多
关键词 PR VIGOROUSLY CARRYING OUT FOREIGN TRADE AGENCY system MODE
下载PDF
Design of Automatic Measurement & Control System in Spectrum and Life-energy
18
作者 Li Ningxi, Yang Zhihu, Huang Xinmin and Su Hong 《IMP & HIRFL Annual Report》 2001年第1期103-103,共1页
The physical research of heavy element in the field of high ionization & little electron is one focus in the international front physical fields.Our research in this field is based on HIRFL and we selectively carr... The physical research of heavy element in the field of high ionization & little electron is one focus in the international front physical fields.Our research in this field is based on HIRFL and we selectively carry through some experiments using different energy ion obtained by accelerator.We design an automatic measurement & control system in spectrum & life-energy in order to do the experiments.The principle of this system is 展开更多
关键词 SPECTRUM ACCELERATOR CARRY IONIZATION CHART SERIAL Wavelength Distance
下载PDF
CHINA CARRIES OUT ENTERPRISE BANKRUPTCY IN A PLANNED WAY
19
《China's Foreign Trade》 2002年第4期12-14,共3页
关键词 CHINA carries OUT ENTERPRISE BANKRUPTCY IN A PLANNED WAY WTO
下载PDF
Estimating the Limits in System Design for 48 V Automotive Power Applications
20
作者 Ulf Schwalbe Marco Schilling Tobias Reimann 《Journal of Electrical Engineering》 2017年第2期100-113,共14页
The design process in power electronics is driven by increased utilisation level of the used components to gain performance whilst keeping cost low. This article provides an overview on challenges in low-voltage high-... The design process in power electronics is driven by increased utilisation level of the used components to gain performance whilst keeping cost low. This article provides an overview on challenges in low-voltage high-current systems, e.g. used in automotive applications. The main content points are: topology selection--single systems vs. cascaded systems, PCB manufacturing technology overview, current measurement methods, bulk capacitor design (ceramic DC link) and PCB design instructions for high-current systems. The PCB design instructions target on optimised thermal design for maximised PCB utilisation and on optimised track design for a low inductance DC link interconnection. The paper bases on calculations, measurements and simulations. 展开更多
关键词 High current application 48V system DC link optimization PCB optimization current carrying capability
下载PDF
上一页 1 2 42 下一页 到第
使用帮助 返回顶部