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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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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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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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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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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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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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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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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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Economical Policy
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《China's Refractories》 CAS 2008年第1期47-48,共2页
China Import Duties of Alumina and Refined Copper to Be Cancelled in 2008;40 Thounsand Tons Molybdenum Smelting Project Commenced;China Began to Place Export Duties on Silicon;SiC Price Will Continue to Rise;Economic ... China Import Duties of Alumina and Refined Copper to Be Cancelled in 2008;40 Thounsand Tons Molybdenum Smelting Project Commenced;China Began to Place Export Duties on Silicon;SiC Price Will Continue to Rise;Economic Running Conditions of China' s Iron and Steel, Non-ferrous, Building Material Industries During January - October. 展开更多
关键词 CNY economical Policy SIC
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Simulation platform of economical operation and dispatch for power plant based on float-coded genetic algorithm
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作者 朱奕 伞冶 马克茂 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2004年第5期506-509,共4页
This paper discusses a float-coded genetic algorithm and its application to the optimization of the power plant operation concerning the simulation problem of economical operation for power plant systems. The method p... This paper discusses a float-coded genetic algorithm and its application to the optimization of the power plant operation concerning the simulation problem of economical operation for power plant systems. The method proposed realizes the load optimization between generating units of power plants and their loads, solves the problem of influence of a unit plant pause spoilage and load variance on the optimal plant combination and load, and finally establishes a simulation platform for the power plant economical operation. 展开更多
关键词 SIMULATION economical operation genetic algorithm
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Economically Challenged Women in Disaster Risk Management: Toward a Resilient Filipino Community
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作者 Teodora Luz S. Mangahas Rosemarie R. Casimiro Arneil G. Gabriel 《Open Journal of Ecology》 2018年第1期42-56,共15页
The social and cultural norms shape gender roles which sometimes deprive women of the opportunity to prepare for natural calamities. But the disastrous effect of natural disasters spares no one. It knows no gender. Mo... The social and cultural norms shape gender roles which sometimes deprive women of the opportunity to prepare for natural calamities. But the disastrous effect of natural disasters spares no one. It knows no gender. Most of the time, women more than men bear the worse of consequences. The study measures and describes the impact of disaster preparedness sessions on the perception of economically challenged women in Philippines. By using a mixed qualitative and quantitative research method the study found that: 1) the majority of women participants are willing to undergo training in disaster preparedness;2) their awareness in disaster preparedness improved from “basic” to “high” level;3) their level of action in disaster preparedness is still on the “planning stage” and;4) the program effectively changed their attitude towards disaster preparedness and mitigation. The study provided insights on the potential of women in disaster preparedness toward a disaster resilient Filipino community. 展开更多
关键词 Sustainable Development GENDER AWARENESS Natural Calamities economically Deprived WOMEN DISASTER AWARENESS
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Analysis on Economical Land Use in the General Drawing Design of Oil Field Stations
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作者 Ning Hong 《Frontiers Research of Architecture and Engineering》 2018年第4期93-97,共5页
This paper takes the analysis of economical land use in the design of oil field stations as the research object.Firstly,it elaborates the significance of saving land.Then combined with the"Fire Prevention Code of... This paper takes the analysis of economical land use in the design of oil field stations as the research object.Firstly,it elaborates the significance of saving land.Then combined with the"Fire Prevention Code of Petrol Chemical Enterprise Design",the paper analyzes and studies the safety and economical use of the general drawing design of the oil field stations for reference. 展开更多
关键词 OIL field STATIONS General DRAWING arrangement economical LAND use
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Energy-Saving and Economical Evaluations of a Ceramic Gas Turbine Cogeneration Plant
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作者 Satoru Okamoto 《Open Journal of Energy Efficiency》 2013年第2期89-96,共8页
A ceramic gas turbine can save energy because of its high thermal efficiency at high turbine inlet temperatures. This paper deals with the thermodynamic and economic aspects of a ceramic gas turbine cogeneration syste... A ceramic gas turbine can save energy because of its high thermal efficiency at high turbine inlet temperatures. This paper deals with the thermodynamic and economic aspects of a ceramic gas turbine cogeneration system. Here cogeneration means the simultaneous production of electrical en-ergy and useful thermal energy from the same facility. The thermodynamic performance of a ceramic gas turbine cycle is assessed using a computer model. This model is used in parametric studies of performance under partial loads and at various inlet air temperatures. The computed performance is compared to the measured performance of a conventional gas turbine cycle. Then, an economic evaluation of a ceramic gas turbine cogeneration system is investigated. Energy savings provided by this system are estimated on the basis of the distributions of heat/power ratios. The computed economic evaluation is compared to the actual economic performance of a conventional system in which boilers produce the required thermal energy and electricity is purchased from a utility. 展开更多
关键词 Energy EXERGY ENERGY-SAVING economical Evaluation CERAMIC Gas Turbine COGENERATION Plant
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