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Evaluation of Economical and Intensive Use of Construction Land in a County Town:A case study of Wan’an County,Ji’an City
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作者 YU Zhijie 《Journal of Landscape Research》 2024年第1期51-54,共4页
Taking the changes of construction land in Wan’an County over the years as the research object,the quantity and spatial characteristics of construction land in Wan’an County were analyzed,and the overall situation a... Taking the changes of construction land in Wan’an County over the years as the research object,the quantity and spatial characteristics of construction land in Wan’an County were analyzed,and the overall situation and regional differences of construction land utilization in Wan’an County were revealed.From the aspects of main influencing factors such as land use structure,land use intensity,land input intensity and output benefit,an evaluation indicator system was established to evaluate the economical and intensive use level of construction land in Wan’an County.The results show that the score of the economical and intensive use level of construction land in Wan’an County was 56.92,which was the lowest among all the districts and counties in Ji’an City.Based on the evaluation results,the corresponding economizing and intensive strategies were put forward,and the safeguard measures for its implementation were explored.The purpose is to provide some support for the preparation of territorial spatial planning,the delineation of urban development boundaries,and the potential exploitation of construction land stock,hoping to improve the utilization efficiency and benefit of construction land in Wan’an County,and promote the economic growth of Wan’an County to the stage of high-quality development. 展开更多
关键词 Construction land economical and intensive utilization EVALUATION
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Studies on the Economical and Practical Temperature Control Facility of Deep-Litter Systems for Swine Production
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作者 林家彬 秦竹 +5 位作者 周忠凯 顾洪如 杨杰 汤赤 陈俊 余刚 《Agricultural Science & Technology》 CAS 2013年第7期1053-1056,共4页
Deep-Litter System is a high yield approach to raise swine with pollution free in a lower cost. In the research, based on the heat stress in summer caused by fermentation, three temperature-control systems were design... Deep-Litter System is a high yield approach to raise swine with pollution free in a lower cost. In the research, based on the heat stress in summer caused by fermentation, three temperature-control systems were designed, including natural ventilation through transoms, forced ventilation via fans, and cooling by hyperbaric spray system. Specifically, the latter intermittent auto-pressurized spray system developed in our lab, which could spray successively via pressure from storage tubes without wetting the fermentation bed, is suitable for the promotion with the deep-litter technology in rural regions , since the power consumption is only 1 kwh per day. 展开更多
关键词 Deep litter system Temperature control facilities Intermittent auto-pressurized spray system economical and practical
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Analysis on the Economical and Intensive Utilization of Regional Construction Land in Zunyi City of Guizhou Province
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作者 兰安军 王昌浩 +1 位作者 钟九生 秦微 《Agricultural Science & Technology》 CAS 2017年第6期1133-1137,共5页
Taking Zunyi City of Guizhou Province as research area, the research performed spatial dynamic analysis and elastic coefficient method to evaluate the e- conomical and intensive utilization of the regional constructio... Taking Zunyi City of Guizhou Province as research area, the research performed spatial dynamic analysis and elastic coefficient method to evaluate the e- conomical and intensive utilization of the regional construction land, and to discuss the decision direction for economical and intensive utilization of the regional con- struction land. The results showed that, the population based land utilization both in Zunyi and the city districts and counties indicated extensive trend. The economy- based land utilization in Zunyi City, as well as in Huichun, Zunyi and Tongzi County presented intensive trend, however the other districts and counties were in extensive tendency. It concluded that the economical and intensive utilization of construction land should be focused on the rural collective construction land, and the potential tapping of rural collective construction land in rocky desertification area should be the first priority, otherwise, the regional economic development was unbalanced be- tween different district and county in Zunyi. 展开更多
关键词 economical and intensive utilization Elastic coefficient Spatial dynamicanalysis Zunyi City
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Decadal variations in the community status of economically important invertebrates in the Bohai Sea 被引量:3
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作者 Qiang Wu Lisha Guan +2 位作者 Zhongyi Li Xiujuan Shan Xianshi Jin 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2019年第10期60-66,共7页
With the decline of fish stocks,the proportions of economically important invertebrates like crustaceans and cephalopods have increased in the Bohai Sea.The community structure and trophic level of economically import... With the decline of fish stocks,the proportions of economically important invertebrates like crustaceans and cephalopods have increased in the Bohai Sea.The community structure and trophic level of economically important invertebrates were analyzed using the bottom trawl survey data collected by the Yellow Sea Fisheries Research Institute in the Bohai Sea in May and August of 1958–1959,1982,1992–1993,2004,2009 and 2015.A total of 37 species of economically important invertebrates,belonging to 5 orders,24 families,were captured.The biomass densities of economically important invertebrates in the Bohai Sea displayed an overall downward trend from 1982 to 2015.Oratosquilla oratoria and Loligo spp.were the most dominant species in the past 30 years,the biomass proportion of O.oratoria increased gradually in both May and August from 1982 to 2015.Moreover,biodiversity indices of economically important invertebrates in the Bohai Sea appeared to decline from 1982 to 2004 and then increased in 2015.Similarly,the mean trophic level of economically important invertebrates declined from 1982 to 2004 and increased slightly in 2015.Overall,although the proportions of invertebrates have increased,the biomass densities in the Bohai Sea have displayed an overall downward trend from 1982 to 2015.The increases in the biodiversity and trophic level of economically important invertebrates after the 2000s,possibly benefit from stock enhancement projects implemented by governments at different levels and national fishery management measures such as the“double-control”of the total number and engine power of fishing vessels and summer moratorium of fishing. 展开更多
关键词 DECADAL VARIATIONS COMMUNITY structure TROPHIC level economically important invertebrates BohaiSea
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Robust sliding mode control for fractional-order chaotic economical system with parameter uncertainty and external disturbance 被引量:3
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作者 周柯 王智慧 +2 位作者 高立克 孙跃 马铁东 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第3期101-106,共6页
This paper presents a modified sliding mode control for fractional-order chaotic economical systems with parameter uncertainty and external disturbance. By constructing the suitable sliding mode surface with fractiona... This paper presents a modified sliding mode control for fractional-order chaotic economical systems with parameter uncertainty and external disturbance. By constructing the suitable sliding mode surface with fractional-order integral, the effective sliding mode controller is designed to realize the asymptotical stability of fractional-order chaotic economical systems. Comparing with the existing results, the main results in this paper are more practical and rigorous. Simulation results show the effectiveness and feasibility of the proposed sliding mode control method. 展开更多
关键词 fractional-order chaotic systems economical system sliding mode control parameter uncertainty
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Comparison of Economical and Technical Indices on Rare Earth Separation Processes of Bastnasite by Solvent Extraction 被引量:2
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作者 严纯华 廖春生 +2 位作者 贾江涛 王明文 李标国 《Journal of Rare Earths》 SCIE EI CAS CSCD 1999年第1期59-64,共6页
According to the composition of rare earth ores and the market, several feasible separation processes of bastnasite in Baotou of Inner Mongolia and Mianning of Sichuan by solvent extraction in HEH(EHP) HCl system wer... According to the composition of rare earth ores and the market, several feasible separation processes of bastnasite in Baotou of Inner Mongolia and Mianning of Sichuan by solvent extraction in HEH(EHP) HCl system were presented. The parameters of the processes such as stage numbers, volume of mixer settler, fixed investment of extractant and rare earths, consumption of chemical reagents including HCl and NH 3 were calculated and compared. The results show that the novel scheme can save cost more than 20% compared with those of others. By the economical analysis, the optimized separation process of bastnasite was obtained, which can be applied to the treatment of monazite too. 展开更多
关键词 Rare earths Bastnasite Solvent extraction economical index Technical index
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Evaluation of the Economical and Intensive Use of Industrial Land in Chizhou Economic and Technological Development Zone 被引量:3
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作者 Rui LIU 《Asian Agricultural Research》 2014年第10期85-90,共6页
Based on the subdivision of industrial land in Chizhou Economic and Technological Development Zone,this paper builds the evaluation indicator system for the economical and intensive use of industrial land in the devel... Based on the subdivision of industrial land in Chizhou Economic and Technological Development Zone,this paper builds the evaluation indicator system for the economical and intensive use of industrial land in the development zone,to analyze the current situation of economical and intensive use of industrial land. The results show that the levels of economical and intensive use of industrial land vary in the development zone; the factors affecting the intensive degree of various industries also vary; the industry in Chizhou Economic and Technological Development Zone is still in the transition phase from inefficient use to low level of use to intensive use. 展开更多
关键词 INDUSTRIAL LAND economical and INTENSIVE use Evalu
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Paths for the Coordinated Development of Rural Economy and Environment in Economically Underdeveloped Areas——A Case of Huaian,China 被引量:2
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作者 TAO Ai-xiang 《Asian Agricultural Research》 2010年第7期42-46,共5页
Taking Huaian as an example,the rural economic and environmental problems in economically underdeveloped areas are expounded.The results show that rural areas in economically underdeveloped areas confront with lagged ... Taking Huaian as an example,the rural economic and environmental problems in economically underdeveloped areas are expounded.The results show that rural areas in economically underdeveloped areas confront with lagged economic development,serious environmental pollutionand scarce shortage of equipments for treating environmental pollution.The causes of problems are analyzed,including inadequate fiscal supportfrom the local government;unscientific system for assessing government officers' performances;backward ideas in environmental protection and im-perfect laws and regulations on environmental protection.Based on these causes,the strategy of employing the circular economy to promote the co-ordinated development of rural environment and economy in economically underdeveloped areas is put forward.The strategy covers transformingthe way of agricultural production;adjusting agricultural production structure;positively collecting funds and increasing the input on handling rural en-vironmental problems;strengthening the efforts on promotion and education,and forming the healthy habits of consumption;enforcing supervisionand establishing a professional administration team for protecting rural environment;laying stress on rural technological innovation and strengtheningthe force of expansion;accelerating the path of industrialization and promoting the industrialization of villages and towns vigorously. 展开更多
关键词 economically underdeveloped areas Rural environment Circular economy Huaian City China
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Economical phase-covariant cloning with multiclones 被引量:1
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作者 张文海 叶柳 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第9期3702-3705,共4页
This paper presents a very simple method to derive the explicit transformations of the optimal economical 1 to M phase-covariant cloning. The fidelity of clones reaches the theoretic bound [D'Ar]ano G M and Macchiave... This paper presents a very simple method to derive the explicit transformations of the optimal economical 1 to M phase-covariant cloning. The fidelity of clones reaches the theoretic bound [D'Ar]ano G M and Macchiavello C 2003 Phys. Rev. A 67 042306]. The derived transformations cover the previous contributions [Delgado Y, Lamata Let al, 2007 Phys. Rev. Lett. 98 150502] in which M must be odd. 展开更多
关键词 quantum cloning economical phase-covariant cloning
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Empirical Study on Factors Influencing Farmland Circulation in Economically Developed Areas 被引量:1
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作者 Chunfang ZHOU 《Asian Agricultural Research》 2013年第12期49-53,58,共6页
Farmland circulation is the foundation of development of regional farmland market.With the aid of survey data of Jiangsu Province and using Heckman two-stage method,this paper analyzed factors influencing farmland cir... Farmland circulation is the foundation of development of regional farmland market.With the aid of survey data of Jiangsu Province and using Heckman two-stage method,this paper analyzed factors influencing farmland circulation from supply and demand of land.Results showed that non-agricultural employment,social security level,and regional economic development level are key factors.In view of these factors,it is recommended to improve rural labor quality,establish perfect rural social security system,and constantly improve rural security level,which are fundamental ways to promoting farmland circulation and improve circulation market. 展开更多
关键词 FARMERS LAND CIRCULATION economically DEVELOPED ar
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Economical Evaluation of a Low-Enthalpy Geothermal Resource Located in an Arid-Zone Area 被引量:1
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作者 Salah Masheitil Brian Agnew +1 位作者 Sara Walker Mosbah Talbi 《Journal of Energy and Power Engineering》 2012年第7期1013-1021,共9页
In this work an economical evaluation that established the viability of a low enthalpy geothermal resource as an energy source in north Africa is presented. The factors considered included the payback period, average ... In this work an economical evaluation that established the viability of a low enthalpy geothermal resource as an energy source in north Africa is presented. The factors considered included the payback period, average rate of return, net present value, and net benefit-cost ratio. The model was based on utilising the energy source to energise four models that comprised thermal equipment consisting of water/air cooled single/half effect lithium bromide water mixture absorption chillers and an R-245fa organic Rankine cycle. These modelled cycles were based on the energy demand for Waddan city a community in southern Libya which has a demand for combined cooling/electricity only or cooling/electricity with district hot water supply. The results revealed that all of the proposed simulated stand-alone models, except the water-cooled half effect chiller, are not economically viable unless they are heavily subsidized or combined with the district hot water supply at least in the winter season. 展开更多
关键词 Libya low-temperature geothermal resources economical analysis IPSEpro organic Rankine cycle absorption chillers.
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Uncertainty in life cycle economical analysis of cassava-based ethanol fuel
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作者 冷如波 戴杜 +1 位作者 陈晓军 王成焘 《Journal of Central South University》 SCIE EI CAS 2005年第S2期65-69,共5页
Biomass ethanol fuel is not only renewable but also environmental-friendly. Guangxi Zhuang Autonomous Region is developing the cassava-based ethanol fuel. Economical performance of the project is the key issue. The tr... Biomass ethanol fuel is not only renewable but also environmental-friendly. Guangxi Zhuang Autonomous Region is developing the cassava-based ethanol fuel. Economical performance of the project is the key issue. The traditional life cycle economical analysis is just a static calculation process. Uncertainty is the character of cassava yield, cost of cassava plant, cassava price, tax rate and gasoline price, and the economical performance of the project is determined by these aspects. This study proposes an economical model of cassava-based ethanol fuel. The method of Monte Carol is used to simulate the economical performance. This method conquers the shortage of the traditional way. The results show that cassava-based ethanol fuel can get survived when the tax is exempted. Finally, the study also evaluates the potential of the economical performance. 展开更多
关键词 UNCERTAINTY life CYCLE economical analysis CASSAVA ETHANOL FUEL
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Technical and Economical Problems of Bituminous Coal Mining in Czech Republic
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作者 Jaroslav Dvoracek (VSB-Technical University of Ostrava, Czech Republic) 《International Journal of Mining Science and Technology》 SCIE EI 1998年第1期5-9,共5页
The historical development of mining industry in Czech Republic, mining industry in new economical conditions, damping program of hituminous coal mining and the damping of mining activity are mentioned in this paper, ... The historical development of mining industry in Czech Republic, mining industry in new economical conditions, damping program of hituminous coal mining and the damping of mining activity are mentioned in this paper, and some important and detail data are given. This paper is not only concerned to mining, but also to social society, so it is of significance to mining industry and otber enterprises. 展开更多
关键词 Czech REPUBLIC TECHNICAL and economical PROBLEMS bituminous joint-stock company
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Ecological and economical significance of homestead forest to the household of the offshore island in Bangladesh
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作者 Kazi Mohammad Masum Mohammed Shafiul Alam M.M.Abdullah-Al-Mamun 《Journal of Forestry Research》 SCIE CAS CSCD 2008年第4期307-310,共4页
An explanatory survey was conducted to assess the contribution of plant diversity to the ecological and socio-economic condition of the rural household in the offshore island of Bangladesh. Assessment was done by mean... An explanatory survey was conducted to assess the contribution of plant diversity to the ecological and socio-economic condition of the rural household in the offshore island of Bangladesh. Assessment was done by means of multistage random sampling. The homestead sizes of the study area were classified into 3 groups viz, large (〉0.25 ha), medium (0.05-0.25 ha) and small (〈0.05 ha) based on the result obtained from a preliminary survey, and a total of 45 homesteads, 15 from each group, were selected randomly for the study. The average annual income from homestead's plant diversity varied from Tk 5730.00 (US$95.5) to Tk 17500.00 (US$291.67). The rural people were mainly dependent on their homegarden for woodfuel and nutritional requirement as forest was unavailable in the island. The rural people here also cultivated the plant species as a safety measure from frequent cyclone. Constraints hindering the development of homestead plantation were identified and suggestions were given such as the adequate supply of seedlings of fast growing native species and conservation of endangered species to meet the demand of the household as well as to keep ecological balance. 展开更多
关键词 BANGLADESH demand economical significance homestead forest offshore island
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Economical and Technical Indices of Decomposition Processes of Typical Rare Earth Minerals in China
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作者 Wang Weisheng Wang Songling +1 位作者 Jia Jiangtao Zhang Zhaobing 《Journal of Rare Earths》 SCIE EI CAS CSCD 2006年第4期428-428,共1页
The typical treatment processes we of main rare earth resources in China, especially the economical and technical indices of the minerals decomposition of such as ionic adsorptive rare earth deposit ore, bastnasite an... The typical treatment processes we of main rare earth resources in China, especially the economical and technical indices of the minerals decomposition of such as ionic adsorptive rare earth deposit ore, bastnasite and mixed with monazite in Baotou, was presented. The dispersive ionic adsorptive rare earth deposit ore, which is enriched on valuable middle and heavy elements, concentrated by bicarbonate precipitation after exchanging with ammonium sulphate solution. Planting and waste liquid should be focused. Bastnasite and/or monazite, which is enriched light rare earth, centralized with high content and capacity,concentrated by gravimetric, magnetic, floating, then decomposed by calcinations and leaching. Waste liquid, gases and dregs should be treated properly. Investors interested in RE industry can find out the technical and economic characters and history of various RE minerals. Engineers and workers in RE industry can also find the differences of the plants, so as to make more efforts on improving management. However, solving environment protection problems for each process should be committed extraordinarily in order to make a sustainable development of RE industry. 展开更多
关键词 mineral decomposition economical and technique indices environment protection rare earths
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Cooperative Game Among Cities in Urban Agglomerations and Economical Sustainable Development
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作者 Shan WeidongGuangdong Polytechnical Normal University,Guangzhou,510665,China 《Chinese Journal of Population,Resources and Environment》 2004年第2期58-62,共5页
This paper analyses redounded profits of cooperation and non-cooperation among cities in urban agglomerations based on game theory. It discusses the problems of economical development among cities with feeble cooperat... This paper analyses redounded profits of cooperation and non-cooperation among cities in urban agglomerations based on game theory. It discusses the problems of economical development among cities with feeble cooperation, and deduces the conclusion that only cooperation of cities produces the maximum profits and realizes Pareto efficiency for cities and urban agglomerations. The paper states that cooperation is the cornerstone of economic sustainable development in urban agglomerations in profits produced by cooperation among cities. Some suggestions to accelerate cooperation among cities are proposed. 展开更多
关键词 Urban Agglomerations City COOPERATION GAME economical Sustainable Development
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Regional Study on Economical Supporting Capacity of Land Resources in Shandong Province
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作者 Li Yujiang Chen Pei'an 《Chinese Journal of Population,Resources and Environment》 北大核心 2007年第1期68-73,共6页
Taking the land resources of 17 cities in Shandong Province as the basic data, the article studied on the economical supporting capacity of land resources in terms of the effect of land on economy. The author classifi... Taking the land resources of 17 cities in Shandong Province as the basic data, the article studied on the economical supporting capacity of land resources in terms of the effect of land on economy. The author classified 17 cities of Shandong Province into four types according to the economical supporting capacity of land resources by quantitatively estimating the evaluation indices of the total amount of land resources, the potential of urban and other nonagricultural land, and the integrated economical sup- porting capacity of land resources, etc. The author proposes the questions requiring further study at the end of this article. 展开更多
关键词 land resources economical supporting capacity quantitative estimation Shandong Province
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Economical Requirements Elicitation Techniques During COVID-19: A Systematic Literature Review
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作者 Tauqeer ul Amin Basit Shahzad +1 位作者 Fazal-e-Amin Muhammad Shoaib 《Computers, Materials & Continua》 SCIE EI 2021年第5期2665-2680,共16页
Requirements elicitation is a fundamental phase of software development in which an analyst discovers the needs of different stakeholders and transforms them into requirements.This phase is cost-and time-intensive,and... Requirements elicitation is a fundamental phase of software development in which an analyst discovers the needs of different stakeholders and transforms them into requirements.This phase is cost-and time-intensive,and a project may fail if there are excessive costs and schedule overruns.COVID-19 has affected the software industry by reducing interactions between developers and customers.Such a lack of interaction is a key reason for the failure of software projects.Projects can also fail when customers do not know precisely what they want.Furthermore,selecting the unsuitable elicitation technique can also cause project failure.The present study,therefore,aimed to identify which requirements elicitation technique is the most cost-effective for large-scale projects when time to market is a critical issue or when the customer is not available.To that end,we conducted a systematic literature review on requirements elicitation techniques.Most primary studies identified introspection as the best technique,followed by survey and brainstorming.This finding suggests that introspection should be the first choice of elicitation technique,especially when the customer is not available or the project has strict time and cost constraints.Moreover,introspection should also be used as the starting point in the elicitation process of a large-scale project,and all known requirements should be elicited using this technique. 展开更多
关键词 COVID-19 software engineering requirements engineering requirements elicitation INTROSPECTION project failure SLR on elicitation techniques large-scale projects economical elicitation techniques costeffective time constraints
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Scheme for implementing an economical phase-covariant quantum cloning machine of distant atomic qubits with single-photon interference
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作者 周彦辉 王磊 赖晓磊 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第5期132-135,共4页
By means of cavity-assisted photon interference, a simple scheme is proposed to implement a symmetric economical phase-covariant quantum cloning machine of two remote qubits, with each in a separate cavity. With our p... By means of cavity-assisted photon interference, a simple scheme is proposed to implement a symmetric economical phase-covariant quantum cloning machine of two remote qubits, with each in a separate cavity. With our present scheme, a high-fidelity cloning machine is realized. Our scheme may be quite useful in terms of distributed quantum information processing. 展开更多
关键词 economical phase-covariant quantum cloning machine distant atomic qubits single-photon inter-ference
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Fuzzy Extensive Economical Control
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作者 He Zhongxiong & Hu Wanjun ( Automation System lnstitute, Northern Jiaotong University,Beijing 100044, P. R. China ) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1997年第1期51-56,共6页
ln this paper, FEEC theory is studied. An economical space is a dynamic model for any scope of certain economy and market . ln an economical space, any point represents some economical area or entity and is assigned a... ln this paper, FEEC theory is studied. An economical space is a dynamic model for any scope of certain economy and market . ln an economical space, any point represents some economical area or entity and is assigned an variable economic condition Any subspace is assigned an variable economic evaluation. FEEC controller operates oz. economic evaluation and the public parts in economic condition. Any adjustment done by FEEC controller asks the point itself to improve other members to meet the requirements. ln this paper, the template for economic condition and economic evaluation is defined , and then the generic type of economical space and FEE. controller is also given. 展开更多
关键词 Fuzzy extension economical control Generic type
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