期刊文献+
共找到3,014篇文章
< 1 2 151 >
每页显示 20 50 100
Evaluation of Economical and Intensive Use of Construction Land in a County Town:A case study of Wan’an County,Ji’an City
1
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
下载PDF
Decadal variations in the community status of economically important invertebrates in the Bohai Sea 被引量:3
2
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
下载PDF
Comparison of Economical and Technical Indices on Rare Earth Separation Processes of Bastnasite by Solvent Extraction 被引量:2
3
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
ThebastnasiteinBaiyun′eboofInnerMongoliaismorethan70%oftheprovenrareearthresourcesalovertheworld.Thesimilaro... ThebastnasiteinBaiyun′eboofInnerMongoliaismorethan70%oftheprovenrareearthresourcesalovertheworld.Thesimilaroreswerediscovered... 展开更多
关键词 RARE earths Bastnasite SOLVENT EXTRACTION economical INDEX TECHNICAL INDEX
下载PDF
Evaluation of the Economical and Intensive Use of Industrial Land in Chizhou Economic and Technological Development Zone 被引量:3
4
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
下载PDF
Paths for the Coordinated Development of Rural Economy and Environment in Economically Underdeveloped Areas——A Case of Huaian,China 被引量:2
5
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
下载PDF
Empirical Study on Factors Influencing Farmland Circulation in Economically Developed Areas 被引量:1
6
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
下载PDF
Technical and Economical Problems of Bituminous Coal Mining in Czech Republic
7
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
下载PDF
Uncertainty in life cycle economical analysis of cassava-based ethanol fuel
8
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
下载PDF
Fuzzy Extensive Economical Control
9
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
FuzzyExtensiveEconomicalControlHeZhongxiong&HuWanjunAutomationSystemlnstitute,NorthernJiaotongUniversity,Bei... FuzzyExtensiveEconomicalControlHeZhongxiong&HuWanjunAutomationSystemlnstitute,NorthernJiaotongUniversity,Beijing100044,P.R.Ch... 展开更多
关键词 FUZZY EXTENSION economical CONTROL GENERIC TYPE
下载PDF
Cooperative Game Among Cities in Urban Agglomerations and Economical Sustainable Development
10
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
下载PDF
Economical Requirements Elicitation Techniques During COVID-19: A Systematic Literature Review
11
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
下载PDF
Simulation platform of economical operation and dispatch for power plant based on float-coded genetic algorithm
12
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
下载PDF
Economically Challenged Women in Disaster Risk Management: Toward a Resilient Filipino Community
13
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
下载PDF
Analysis on Economical Land Use in the General Drawing Design of Oil Field Stations
14
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
下载PDF
Energy-Saving and Economical Evaluations of a Ceramic Gas Turbine Cogeneration Plant
15
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
下载PDF
To Raise Safe and Economical Operation Level on Scientific and Technical Progress Basis
16
《Electricity》 1997年第1期20-22,共3页
关键词 To Raise Safe and economical Operation Level on Scientific and Technical Progress Basis
下载PDF
Economical Cars to Lead China's Auto Market
17
《China's Foreign Trade》 2000年第9期36-36,共1页
关键词 AUTO economical Cars to Lead China’s Auto Market
下载PDF
Economical effect of lumen apposing metal stents for treating benign foregut strictures 被引量:3
18
作者 Alexander Hallac Wichit Srikureja +3 位作者 Eashen Liu Parag Dhumal Ashish Thatte Nishant Puri 《World Journal of Gastrointestinal Endoscopy》 CAS 2018年第10期294-300,共7页
AIM To evaluate the clinical and economical efficacy of lumen apposing metal stent(LAMS) in the treatment of benign foregut strictures.METHODS A single center retrospective database of patients who underwent endoscopi... AIM To evaluate the clinical and economical efficacy of lumen apposing metal stent(LAMS) in the treatment of benign foregut strictures.METHODS A single center retrospective database of patients who underwent endoscopic treatment of benign foregut strictures between January 2014 and May 2017 was analyzed. A control group of non-stented patients who underwent three endoscopic dilations was compared to patients who underwent LAMS placement. Statistical tests performed included independent t-tests and fiveparameter regression analysis RESULTS Nine hundred and ninety-eight foregut endoscopic dilations were performed between January 2014 and May 2017. 15 patients underwent endoscopic LAMS placement for treatment of benign foregut stricture. Thirty-six patients with recurrent benign foregut strictures underwent three or more endoscopic dilations without stent placement. The cost ratio of endoscopic dilation to LAMS(stent, placement and retrieval) is 5.77. Cost effective analysis demonstrated LAMS to be economical after three endoscopic dilation overall.LAMS was cost effective after two dilations in the Postsurgical stricture subgroup. CONCLUSION Endoscopists should consider LAMS for the treatment of benign foregut strictures if symptoms persist past three endoscopic dilations. Post-surgical strictures may benefit from LAMS if symptoms persist after two dilations in a post-surgical. Early intervention with LAMS appears to be a clinically and economically viable option for durable symptomatic relief in patients with these strictures. 展开更多
关键词 BENIGN ESOPHAGEAL STRICTURE Endoscopy ECONOMICS Stent ECONOMICS Self expandable metallic stents ESOPHAGEAL diseases
下载PDF
The Grey Correlation Analysis on the Relationship between the Rural Finance and the Rural Economical Growth in Sichuan Province 被引量:3
19
作者 ZHANG Xiao-fang QI Yan-bin 《Asian Agricultural Research》 2011年第1期77-79,84,共4页
This paper analyzes the relationship between rural finance and the rural economy of Sichuan Province from 1999 to 2009 by using the sequential growth rate of the gross value of farming, forestry, animal husbandry and ... This paper analyzes the relationship between rural finance and the rural economy of Sichuan Province from 1999 to 2009 by using the sequential growth rate of the gross value of farming, forestry, animal husbandry and fishery and the sequential growth rate of the per capital total income of rural households as the indicators of rural economic development; and taking the volume of deposit, volume of credit, volume of agricultural credit and the credit volume of township enterprises as the indicators of rural financial development; as well as the method of grey correlation analysis. The results show that there is an obvious positive correlation between them, and the development of country finance has the closest connection with the sequential growth rate of farming, forestry, animal husbandry, sideline production and fishery. The loan scale of township enterprises has the biggest influence on the increase of the rural economy. The countermeasures are put forward, covering optimizing investment structure; supporting the development of township enterprises; encouraging loan; actively lightening the financial difficulties in the process of developing rural economy; innovating and exploring; and promoting the diversified development of rural finance. 展开更多
关键词 Rural finance development Rural economic growth Grey correlation analysis China
下载PDF
Sources of inaccuracy when estimating economically optimum N fertilizer rates 被引量:1
20
作者 Martin Bachmaier 《Agricultural Sciences》 2012年第3期331-338,共8页
Nitrogen rate trials are often performed to determine the economically optimum N application rate. For this purpose, the yield is modeled as a function of the N application. The regression analysis provides an estimat... Nitrogen rate trials are often performed to determine the economically optimum N application rate. For this purpose, the yield is modeled as a function of the N application. The regression analysis provides an estimate of the modeled function and thus also an estimate of the economic optimum, Nopt. Obtaining the accuracy of such estimates by confidence intervals for Nopt is subject to the model assumptions. The dependence of these assumptions is a further source of inaccuracy. The Nopt estimate also strongly depends on the N level design, i.e., the area on which the model is fitted. A small area around the supposed Nopt diminishes the dependence of the model assumptions, but prolongs the confidence interval. The investigations of the impact of the mentioned sources on the inaccuracy of the Nopt estimate rely on N rate trials on the experimental field Sieblerfeld (Bavaria). The models applied are the quadratic and the linear-plus-plateau yield regression model. 展开更多
关键词 Confidence Interval Economic Optimum N Rate Trials Quadratic Model Linear-plus-Plateau Model
下载PDF
上一页 1 2 151 下一页 到第
使用帮助 返回顶部