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Numerical Modeling and Technico-Economic Analysis of a Hybrid Energy Production System for Self-Consumption: Case of Rural Area in the Comoros
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作者 Fahad Maoulida Mohamed Aboudou Kassim +2 位作者 Rabah Djedjig Ahmed Ihlal Mohammed El Ganaoui 《Journal of Power and Energy Engineering》 2024年第5期24-59,共36页
This study aims to provide electricity to a remote village in the Union of Comoros that has been affected by energy problems for over 40 years. The study uses a 50 kW diesel generator, a 10 kW wind turbine, 1500 kW ph... This study aims to provide electricity to a remote village in the Union of Comoros that has been affected by energy problems for over 40 years. The study uses a 50 kW diesel generator, a 10 kW wind turbine, 1500 kW photovoltaic solar panels, a converter, and storage batteries as the proposed sources. The main objective of this study is to conduct a detailed analysis and optimization of a hybrid diesel and renewable energy system to meet the electricity demand of a remote area village of 800 to 1500 inhabitants located in the north of Ngazidja Island in Comoros. The study uses the Hybrid Optimization Model for Electric Renewable (HOMER) Pro to conduct simulations and optimize the analysis using meteorological data from Comoros. The results show that hybrid combination is more profitable in terms of margin on economic cost with a less expensive investment. With a diesel cost of $1/L, an average wind speed of 5.09 m/s and a solar irradiation value of 6.14 kWh/m<sup>2</sup>/day, the system works well with a proportion of renewable energy production of 99.44% with an emission quantity of 1311.407 kg/year. 99.2% of the production comes from renewable sources with an estimated energy surplus of 2,125,344 kWh/year with the cost of electricity (COE) estimated at $0.18/kWh, presenting a cost-effective alternative compared to current market rates. These results present better optimization of the used hybrid energy system, satisfying energy demand and reducing the environmental impact. 展开更多
关键词 Hybrid system Rural Area Electrification COMOROS Techno-economic Analysis PV-Wind-Diesel-Battery Meteorological Data HOMER Energy Pro
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Open multilevel hierarchic intelligent control system for eco-industrial system
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作者 陈静 张文红 《Journal of Southeast University(English Edition)》 EI CAS 2006年第2期242-247,共6页
In allusion to the characteristics of the open complex giant system, an open multilevel hierarchic intelligent control system is established for the eco-industrial system. With the idea of the open engineering system,... In allusion to the characteristics of the open complex giant system, an open multilevel hierarchic intelligent control system is established for the eco-industrial system. With the idea of the open engineering system, using the hall for workshop of metasynthetic engineering (HWME), intelligent control techniques, the expert system and the design of experiments are integrated within the framework of the nonlinear multiobjective decision support system to develop a robust, top-level design specification so as to make the system have the quality of adaptive control, self-organizing, self-learning and robustness. Finally, an illustrative example is given to clarify the effectiveness of the method. 展开更多
关键词 eco-industry complex giant systems hall for workshop of metasynthetic engineering open engineering system intelligent control nonlinear multi-objective
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Economic Analysis of Diversified Rotational Cropping Systems in the Lateritic Belt of Lower Gangetic Plain of Eastern India 被引量:2
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作者 D. Mandal K. Baral +2 位作者 D. C. Ghosh J. Timsina M. K. Dasgupta 《Journal of Agricultural Science and Technology(B)》 2011年第3期331-341,共11页
Economic analysis of different diversified rotational cropping systems under Farmers' package/practices and improved package/practices was conducted in Birbhum district, West Bengal, located in the red and lateritic ... Economic analysis of different diversified rotational cropping systems under Farmers' package/practices and improved package/practices was conducted in Birbhum district, West Bengal, located in the red and lateritic belt of lower Gangetic plain of eastern lndia. Diversified triple cropping systems (peanut-brinjal+brinjal, rice-potato-pumpkin, and cucumber-cabbage-basella) required higher cost for cultivation, but also produced higher rice equivalent yield, higher net return and higher return rupee1 invested in both management practices. Considering the resource-ability and risk-bearing capacity, and net return and return rupee^-1 (RPR) invested, these cropping systems can be recommended for resource-rich farmers. Rice-rapeseed-cowpea, rice-wheat-green gram and radish-tomato-amaranthus systems profitable. These cropping systems can be required less inputs for cultivation, were less risky, and economically viable and recommended for resource-poor farmers. Peanut-brinjal + brinjal-okra-chilli + chilli-cucumber-cabbage-basella system was the best among all the 3-year rotational systems in respect to RPR in both management practices. This rotational system will be suitable for resource-rich farmers. Vegetable-based rotational systems (ridge gourd-marigold-okra-black gram-pointed gourd + pointed gourd-radish-tomato-amaranthus) or rice-based rotational system (rice-wheat-green gram-rice-rapeseed-cowpea-rice-potato-pumpkin) also found to be suitable to increase the profitability and system sustainability. These cropping systems can be recommended for all groups of farmers. 展开更多
关键词 Cropping systems rotational cropping systems PRODUCTIVITY economics west Bengal India.
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A Comparative Study of the Economic Feasibility of Employing CHP Systems in Different Industrial Manufacturing Applications 被引量:1
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作者 Chad A. Wheeley Pedro J. Mago Rogelio Luck 《Energy and Power Engineering》 2011年第5期630-640,共11页
Extensive research work including multiple methodologies and numerous simulations have been completed in order to determine the economic effectiveness of employing CHP at commercial and residential sites. In contrast ... Extensive research work including multiple methodologies and numerous simulations have been completed in order to determine the economic effectiveness of employing CHP at commercial and residential sites. In contrast to the above, very few attempts have been made to develop methodologies to study the feasibility of CHP systems at industrial manufacturing facilities. As a result, practical opportunities for CHP at industrial sites are often not realized or even investigated. It follows that there is a need in the CHP related literature for an analysis that is explicit and yet general enough to determine the economic viability and potential for success of CHP systems at industrial manufacturing facilities. Therefore, the purpose of this paper is to clearly outline a methodology to determine the economic effectiveness of installation and operation of a CHP system at industrial facilities that have a need for space or process heating in the form of steam. The effect on the CHP system economic performance of several parameters, such as the project payback, internal rate of return, net present value, etc., are considered in the proposed methodology. The applicability and generality of the methodology is illustrated by examples including four different manufacturing facilities. The effects of the variability of factors such as annual facility operational hours during which both process heat and electricity are needed, facility average hourly thermal load, cost of utility supplied electricity, and CHP fuel type and associated fuel cost, on the outcome of the economic analysis are also examined. 展开更多
关键词 CHP systems CHP For INDUSTRIAL Manufacturing Facilities economIC FEASIBILITY Study
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Research on the Knowledge System Framework of Eco-industrial Engineering
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作者 Li Chunfa Wang Xiangli +1 位作者 Luo Yanbing Li Mengmeng 《Chinese Journal of Population,Resources and Environment》 2012年第3期72-83,共12页
With intensified contradiction between the rapid devel- opment of modem industry and the carrying capacity of natural environment, coordinating the relationship between economic benefits and ecological benefits is a s... With intensified contradiction between the rapid devel- opment of modem industry and the carrying capacity of natural environment, coordinating the relationship between economic benefits and ecological benefits is a significant issue to be solved for modem industrial engineering. This paper firstly conducts the comparative analysis between traditional and ecological industry as well as traditional and modem industrial engineering, and in- dicates that eco-industrial engineering is an inevitable choice for sustainable development of modem industrial engineering; Then, based on industrial ecology, environmental economics and sustain- able development theory, the connotation and definition of eco- industrial engineering are proposed, and the theoretical and practi- cal development of the concepts of eco-industrial engineering are further investigated. Furthermore, the research subject, research content, academic system architecture and evaluation methods of eco-industrial engineering are discussed. Finally, combining the current scientific and technological development, we put forward the important scientific value and practical significance of con- structing eco-industrial engineering for the utilization of these concepts. 展开更多
关键词 eco-industrial engineering knowledge system frame-work sustainable development economic benefits ecologicalbenefits
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Economic Potential of Compost Amendment as an Alternative to Irrigation in Maine Potato Production Systems
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作者 John M. Halloran Robert P. Larkin +2 位作者 Sherri L. DeFauw O. Modesto Olanya Zhongqi He 《American Journal of Plant Sciences》 2013年第2期238-245,共8页
Potato productivity in the northeastern US has been relatively constant for over 50 years, raising questions about what factors are limiting productivity. Research was initiated in 2004 to identify key constraints to ... Potato productivity in the northeastern US has been relatively constant for over 50 years, raising questions about what factors are limiting productivity. Research was initiated in 2004 to identify key constraints to potato productivity by evaluating Status Quo (SQ), Soil Conserving (SC), and Soil Improving (SI) cropping systems under both rainfed and irrigated management, and it was found that addition of compost or irrigation substantially increased yield. In this study, we employed partial budgeting to determine cost differences and their impact on net revenue for these cropping systems. Differences in systems were primarily associated with rotation length, tillage operations, compost and application expenses, and water management practices. When compost (as composted dairy manure) was annually applied at 19 Mg haf-1 and evaluated over the entire 3-year crop rotation cycle, the compost-amended rainfed SI system was more expensive to maintain than the irrigated SC system if compost cost exceeded $3.63 Mg-1. Average marketable yields were used to calculate gross and net revenue for each system. Because average potato yield for the irrigated SQ system (28.4 Mg·ha-1) equaled that in the rainfed SI system (28.3 Mg·ha-1), we were able to compare cost of irrigation versus compost for achieving comparable yield. The compost-amended SI system under rainfed management generated more net revenue from the potato crop than the irrigated SQ system when compost costs were less than $7.42 Mg-1. When compared to the commonly used rainfed SQ system, rainfed SI achieved higher net revenue as long as compost cost was less than $22.95 Mg-1. The rainfed SI system achieved higher net revenue than the irrigated SC system when compost cost was $9.43 Mg-1or less, but generated greater net revenue than the rainfed SC system regardless of compost costs, due to substantially higher yields associated with compost amendment. This investigation demonstrates that compost is a potentially viable substitute to irrigation for potato in the northeastern US;however, such potential is highly dependent on suitable compost sources and application costs. 展开更多
关键词 COMPOST Cropping systems economIC POTENTIAL IRRIGATION Partial BUDGETING Potato Production Water Stress Yield
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Topology of economic systems
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作者 Mark Klinedinst Charles Rock 《Chinese Business Review》 2009年第6期14-25,共12页
An economic topology can have many uses to the academician, student and practitioner. Refining a topology of economic systems helps to bring together seemingly disparate characteristics and to point out potential long... An economic topology can have many uses to the academician, student and practitioner. Refining a topology of economic systems helps to bring together seemingly disparate characteristics and to point out potential long run trends. The progression of economic systems over time and also brief explanations of each system are given. We argue that most modem economic systems have some remnants of earlier forms, that is, most economies today are some mixture of what might be considered pure systems. Measurable characteristics to identify a particular system are developed that allows progress to or from a particular classification to be charted for individual countries. 展开更多
关键词 economic systems CAPITALISM SOCIALISM TRANSITION labor-managed
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On the Dynamic Mechanism of the Constitutional System in Promoting Economic Development -- Analysis of the Institutional Economics
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作者 Lin Xiaowen 《学术界》 CSSCI 北大核心 2015年第1期266-270,共5页
According to the basic principles of institutional economics,the Constitutional system is the underlying causes to promote the economic development.The CPC Central Committee is the source of motivation to promote econ... According to the basic principles of institutional economics,the Constitutional system is the underlying causes to promote the economic development.The CPC Central Committee is the source of motivation to promote economic development by the startup mechanism of Constitution am endment,and the political interpretation of the Constitution is the basic way to promote economic development.The economic development in China has challenged the Constitutional system,calling for the appropriate adjustments to the Constitutional system so as to maintain the sustainable and stable development of the economy in China. 展开更多
关键词 经济发展 启动机制 经济学分析 体制 持续稳定发展 制度经济学 中国经济 修正案
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Comparative Analysis on Two Accounting Systems of Rural Economic Originations
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作者 HU Yu-ling School of Finance and Economics,Yellow River Conservancy Technical Institute,Kaifeng 475003,China 《Asian Agricultural Research》 2011年第4期99-102,106,共5页
In order to normalize the financial account of two kinds of economic organizations,the comparative analysis is conducted on the Accounting System of Village Collective Economic Organization and Accounting System of Fa... In order to normalize the financial account of two kinds of economic organizations,the comparative analysis is conducted on the Accounting System of Village Collective Economic Organization and Accounting System of Farmers’ Cooperatives(Trial) issued by the Ministry of Finance.The comparison points out that application and accounting principles of the two kinds of accounting systems are different.The differences and similarities of the five accounting elements are analyzed including property,liabilities,rights of owners,costs and profits and losses,as well as the reasons of the differences and similarities.Results show that both of the two accounting systems reflect the principles of simplification and clarification.The village collective accounting system works in rural village committee,which acts the administrative duties,the features of concerted benefits of it is showed.While the accounting system of farmers’ cooperatives is based on the village collective accounting system and combines the norms of accounting system of enterprises,so the system represents the demands of collaboration and profit-making. 展开更多
关键词 VILLAGE COLLECTIVE economIC organizations Farmers’
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Causal Relation Analysis of Economic Systems and the improvement of Syetem Dynamis(1)(2)
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作者 Zan Tingquan(Northwest Development Institute, Lanzhou University, Lanzhou 730000, people’s Republic of China)Zhang Qinling(Department of Mathematics, Tianshui Normal College, Tianshui 741000, Gansu Province, P.R.China) 《天水师范学院学报》 1991年第4期73-82,共10页
The Causal relation and whole-part relation are the two fundamen-tal relations in economics.In this paper,on the basis of economic prob-lems analysis in practioce,some causal relation structures of economic sys-tems a... The Causal relation and whole-part relation are the two fundamen-tal relations in economics.In this paper,on the basis of economic prob-lems analysis in practioce,some causal relation structures of economic sys-tems and fundamental rules for operations research are,at first,prop-osed.And then,a quotienting(simplifying)analysis approach of eco-nomic causal relations is presented and discussed in detail.At last,animprovement framework of system dynamics is proposed based on theviewpoint of generalized causal relations analysis. 展开更多
关键词 economIC system CAUSAL RELATION CAUSAL MiniEnvi-ronment Quotienting Analysis.
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Economic Model Predictive Control for Hot Water Based Heating Systems in Smart Buildings
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作者 M. A. Ahmed Awadelrahman Yi Zong +1 位作者 Hongwei Li Carsten Agert 《Energy and Power Engineering》 2017年第4期112-119,共8页
This paper presents a study to optimize the heating energy costs in a residential building with varying electricity price signals based on an Economic Model Predictive Controller (EMPC). The investigated heating syste... This paper presents a study to optimize the heating energy costs in a residential building with varying electricity price signals based on an Economic Model Predictive Controller (EMPC). The investigated heating system consists of an air source heat pump (ASHP) incorporated with a hot water tank as active Thermal Energy Storage (TES), where two optimization problems are integrated together to optimize both the ASHP electricity consumption and the building heating consumption utilizing a heat dynamic model of the building. The results show that the proposed EMPC can save the energy cost by load shifting compared with some reference cases. 展开更多
关键词 Building ENERGY Management system DEMAND Response economIC Model PREDICTIVE Control Heat PUMPS Smart Buildings Thermal ENERGY Storage
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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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Relationship between ecological economics and circular economy,eco-industry,cleaner production,and other relevant categories 被引量:5
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作者 Ma Chuandong 《Ecological Economy》 2006年第4期338-347,共10页
Eco-industry, circular economy, cleaner production, industrial ecology or industrial ecosystem and other subjects are all categories related to sustainable developinent. This paper studies the relations and difference... Eco-industry, circular economy, cleaner production, industrial ecology or industrial ecosystem and other subjects are all categories related to sustainable developinent. This paper studies the relations and differences between the four categories and sustainable development as well as ecological economics. Circular economy, eco-industry, industrial ecosystem and cleaner production were put forward during the revolution in “end treatment pattern” of traditional industrial society. Industrial ecology, eco-industry and circular economy theory are three content expansions of cleaner production. Ecological economics is of instructive function theoretically and methodologically for circular economy, eco-industrial, cleaner production and industrial ecology. Circular economy theory is easier to be accepted, compared with ecological economics theory. And circular economy in nature is the complete application of ecological economics theory. 展开更多
关键词 Circular economy Eco-industry Cleaner production Ecological economics RELATIONSHIP
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Degree of coupling and coordination of eco-economic system and the influencing factors: a case study in Yanchi County, Ningxia Hui Autonomous Region, China 被引量:13
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作者 LU Huiling ZHOU Lihua +2 位作者 CHEN Yong AN Yiwei HOU Caixia 《Journal of Arid Land》 SCIE CSCD 2017年第3期446-457,共12页
Based on the statistical data, we analyzed and evaluated the degree of coupling and coordination of the eco-economic system in Yanchi County for the period spanning from 1983 to 2014. The eco-economic system can be di... Based on the statistical data, we analyzed and evaluated the degree of coupling and coordination of the eco-economic system in Yanchi County for the period spanning from 1983 to 2014. The eco-economic system can be divided into socioeconomic and ecological sub-systems and their relationship can reveal the interaction state between the two sub-systems and help the local government to establish a coordinated development mode. An index system was constructed to assess the development of the two sub-systems before the evaluation of the degree of coupling and coordination. The principal component regression analysis was adopted to quantitatively assess the influences of natural, economic and social factors on the degree of coupling and coordination of the eco-economic system. Results showed that, from 1983 to 2014, the development trends of both sub-systems were increasing with the ecological sub-system having more fluctuations. The degree of coupling and coordination of the eco-economic system in the study area increased gradually from 1983 to 2014, but experienced five different development stages from the verge of disorder to favorable coordination. The development of the local social and economic conditions was the most important factor influencing the degree of coupling and coordination. The second most important factor was the financial support from the local government. In addition, the environment protection policies also played undeniable roles. Due to the diversity of the influence factors, the government should take comprehensive measures to promote the sustainable development of the eco-economic system. 展开更多
关键词 degree of coupling and coordination eco-economic system ecological sub-system socioeconomic sub-system YanchiCounty
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Selective maintenance problem for series–parallel system under economic dependence 被引量:4
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作者 Qing-zheng XU Le-meng GUO +1 位作者 He-ping SHI Na WANG 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2016年第5期388-400,共13页
In view of the high complexity of the objective world, an economic dependence between subsystems(paired and unpaired) is proposed, and then the maintenance cost and time under different economic dependences are formul... In view of the high complexity of the objective world, an economic dependence between subsystems(paired and unpaired) is proposed, and then the maintenance cost and time under different economic dependences are formulated in a simple and consistent manner. Selective maintenance problem under economic dependence(EDSMP) is presented based on a series–parallel system in this paper. A case study shows that the system reliability is promoted to a certain extent, which can validate the validity of the EDSMP model. The influence of the ratio of set-up cost on system performance is mainly discussed under different economic dependences. Several existing improvements of classical exhaust algorithm are further modified to solve a large sized EDSMP rapidly. Experimental results illustrate that these improvements can reduce CPU time significantly.Furthermore the contribution of each improvement is defined here, and then their contributions are compared thoroughly. 展开更多
关键词 Selective maintenance economic dependence Series–parallel system Exhaust algorithm
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Industrial Structural Changes in Hong Kong,China under One Country,Two Systems Framework
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作者 Simon Xiaobin ZHAO Carola B RAMóN-BERJANO 《Chinese Geographical Science》 SCIE CSCD 2012年第3期302-318,共17页
Hong Kong has undergone substantial economic transformations and developed into a sophisticated busi- ness and financial center in the Asia-Pacific region, since the return of sovereignty to China as a Special Adminis... Hong Kong has undergone substantial economic transformations and developed into a sophisticated busi- ness and financial center in the Asia-Pacific region, since the return of sovereignty to China as a Special Administrative Region under the One Country Two Systems (OCTS) in 1997. This paper discusses and analyzes the industrial struc- tural changes of Hong Kong in recent decades as well as its future challenges and opportunities, The data and finding reveal that even though Hong Kong will face fierce competition from the Mainland's cities as the rise of China, the important role as a bridge between China and the rest of the world wilt brace Hong Kong itself under the OCTS for developing into a service hub for business and trade in the Asia-Pacific region. 展开更多
关键词 economic transformation Hong Kong industrial structural changes One Country Two systems
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COMPLEX ECOLOGIC-ECONOMIC SYSTEM OF AFFORESTATION-AN EXAMPLE OF SUSTAINABLE AGRICULTURE 被引量:2
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作者 李孝芳 《Chinese Geographical Science》 SCIE CSCD 1994年第2期168-173,共6页
The paper deals with a transformation model of a backward distric into a prosperous one. The district is geographically located in Lixiahe region, Jiangsu Province. The region had long ben known as one of the poorest ... The paper deals with a transformation model of a backward distric into a prosperous one. The district is geographically located in Lixiahe region, Jiangsu Province. The region had long ben known as one of the poorest area in China, and had been alternatively attacked by flood, waterlogging, drought, salinzation, and plague of insect. Since the seventies of this centruy efforts to open up trenches on lowland and to level up the shoaly land have been made. A kind of tree, which is tolerable to high watertable, was used to afforest the land. Cereal crop, vegetable and beaus are grown. In some cases, the shoaly land is used for sheep grazing and fishery. A favorable combination of forestry, agriculture, animal husbandry and fishery has been set up in the region. There are five type of managements in the system: 1) forestry-agriculture comPlex management. 2) forestry-fishery complex management, 3) forestry-aquatic plan-fishery complex management, 4) forestry-animal husbandry complex management, and 5) forestry-edible mushroom complex management. The principles and ecological benefits of this system can be identitied: 1) Increase soil fertility by piling mud from marsh land on top soil, and thicken the arable layer. 2) Enhance the utilization rate of sunlight and energy, due to the change of microclimate in field. 3) As a result of multiple layer cultivation and multi-cropping, the production has been greatly increased. 4) Accelerate the cycling of matter and conversion of energy and nutrient of the system. 5) Decrease the consUmption of soil fertility and increase the capability of controlling insect pests. 6) Improve ecological environment by afforestationl. 7) Raise income and provide jobs for local peasants, even some ones from other part of this province. 展开更多
关键词 Lixiahe region complex ecologic-economic system of AFFORESTATION SUSTAINABLE AGRICULTURE agroforestry
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Studies on Technique of Reducing Methane Emission in a Rice-Duck Ecological System and the Evaluation of Its Economic Significance 被引量:5
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作者 XIANG Ping-an HUANG Huang +3 位作者 HUANG Mei GAN De-xin ZHOU Yan FU Zhi-qiang 《Agricultural Sciences in China》 CAS CSCD 2006年第10期758-766,共9页
The rice-duck ecological system is one of the major practices of the traditional Chinese agriculture. A study on the effect of reducing methane emission using this practice provided theoretical and practical basis for... The rice-duck ecological system is one of the major practices of the traditional Chinese agriculture. A study on the effect of reducing methane emission using this practice provided theoretical and practical basis for further development and utilization of this classical agricultural technique. The effect of reducing methane emission and the economic benefits of rice-duck ecological system were studied by carrying out a field experiment and by using economic methodology. The daily variation of CH4 emission in late rice paddy field was basically consistent with the daily variation of atmospheric temperature. The highest emission occurred at the full tillering stage of late rice with a rate of 24.1 or 32.2 or 40.5 mg m^-2 h^-1 in no-tillage area with duck and no-tillage area without duck and conventional-tillage area without duck, respectively. The inhibition of methane emission was apparently effective in the rice-duck ecological system during the initial tillering stage and the full tillering stage. Compared to the no-tillage area without duck, methane emission decreased by 2.333 g m^-2. Compared to the conventional-tillage area without duck, methane emission decreased by 4.723 g m^-2. During the production period of late rice, the amount of methane emission in no-tillage area with duck was 3.373 g m^-2 lesser than that of no-tillage area without duck, and 5.59 g m^-2 less than that of conventional-tillage without duck area. The economic significance was analyzed. Farmers adopting the rice-duck ecological system obtained 2 166 and 4 207 RMB yuan ha^-1 more income than those who adopted a no-tillage without duck technique or conventional-tillage without duck technique, respectively. In addition to the reduction of the environmental pollution by methane emission, the farmers who adopted the rice-duck ecological system achieved economic benefits of 5 000 RMB yuan ha^-1, which was 2 206 and 4 274 RMB yuan ha^-1 more than those who adopted a no-tillage without duck technique and a conventional-tillage without duck technique, respectively. The rice-duck ecological system not only increased the economic benefits for farmers, but also reduced methane emission in rice paddy field. A sustainable agricultural production mode was formed. 展开更多
关键词 NO-TILLAGE late rice rice-duck system methane emission mitigation options economic evaluation
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Regional container transportation system for Northeast Asia economic cooperation in the 21^(st) century 被引量:3
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作者 JIN Feng-jun (Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China) 《Journal of Geographical Sciences》 SCIE CSCD 2000年第4期59-66,共8页
In this paper, the roles of infrastructure development and transportation coordination for Northeast Asian economic cooperation are discussed. It would be necessary to establish an efficient transportation network as ... In this paper, the roles of infrastructure development and transportation coordination for Northeast Asian economic cooperation are discussed. It would be necessary to establish an efficient transportation network as soon as possible. 'Hub-and-Spoke'transportation system and China-Korean peninsula railway container transportation system might be more significant for regional economic cooperation. 展开更多
关键词 INFRASTRUCTURE economic cooperation transportation organization Hub-and-Spoke system high-speed transport
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A STUDY ON STRUCTURAL ANALYSIS OF SUBURBAN ECOLOGICAL AND ECONOMIC SYSTEM ─Taking Tianjin Suburbs and Counties for Example 被引量:1
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作者 张宝光 《Chinese Geographical Science》 SCIE CSCD 1995年第2期125-136,共12页
Along with the development of urban economy. the growth of urban population and the increase of needs of urban society, the suburban ecological and economic system changes constantly and profoundly in its structure an... Along with the development of urban economy. the growth of urban population and the increase of needs of urban society, the suburban ecological and economic system changes constantly and profoundly in its structure and function.Intensifying the research on structural analysis of suburban ecological and economic system is of great significance for grasping light the laws governing the development and evolution of the suburban ecological and economic system and leading this system onto a path of sound circle. By making comprehensive use of the cluster analysis and latent structural analysis the author attempts to explore a new avenue of revealing the structure of suburban ecological and economic system, taking Tianjin suburbs and counties as an example. The results obtained from the above-stated analyses show that it is entirely possible and extremely effective to study the structure and function of suburban ecological and economic system and provide scientific evidence for control of this system by using mathematical methods and statistical analyses. 展开更多
关键词 SUBURBAN ECOLOGICAL and economIC system cluster ANALYSIS latent STRUCTURAL ANALYSIS
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