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51.
Results of experiments conducted on a large-scale integral PSB-VVéR bench and directed toward investigation of the performance of new passive safety systems for nuclear plants with a water-cooled power reactor, an additional system for passive flooding of the active zone, and a system for the passive removal of heat from steam generators are presented. __________ Translated from élektricheskie Stantsii, No. 9, September 2007, pp. 7–10.  相似文献   
52.
黄河小浪底郑州集中控制系统的实现   总被引:2,自引:0,他引:2  
黄河小浪底郑州集中控制系统将多个相互联系的不同专业领域子系统有机地连接成一个整体。文中介绍了该系统的硬件配置和主要功能,并简单介绍了该系统所采用的网络安全措施。  相似文献   
53.
做好闸坝定期巡检确保安全运行   总被引:1,自引:0,他引:1  
王金强 《大坝与安全》2007,(2):16-19,24
根据国家电力监管委员会《水电站大坝运行安全管理规定》和《混凝土大坝安全监测技术规范》对巡视检查工作的具体要求,结合映秀湾水力发电总厂所辖三座闸坝运行的实际,阐述闸坝安全巡视工作的作用及应重点做好的定期检查及日常巡检工作的内容和要求.  相似文献   
54.
Burn or bury? A social cost comparison of final waste disposal methods   总被引:1,自引:0,他引:1  
This paper evaluates the two well-known final waste disposal methods, incineration and landfilling. In particular we compare the social cost of two best-available technologies using a point estimate based on private and environmental cost data for the Netherlands. Not only does our comparison allow for Waste-to-Energy incineration plants but for landfills as well. The data provide support for the widespread policy preference for incineration over landfilling only if the analysis is restricted to environmental costs alone and includes savings of both energy and material recovery. Gross private costs, however, are so much higher for incineration, that landfilling is the social cost minimizing option at the margin even in a densely populated country such as the Netherlands. Furthermore, we show that our result generalizes to other European countries and probably to the USA. Implications for waste policy are discussed as well. Proper treatment of and energy recovery from landfills seem to be the most important targets for waste policy. Finally, WTE plants are a very expensive way to save on climate change emissions.  相似文献   
55.
吴遵  方兆本 《价值工程》2004,23(7):64-68
基金业绩的持续性是指业绩优秀的基金以后一段时间继续保持优秀的业绩,而业绩差的基金继续表现出差的业绩。如果基金具有持续性,对于投资者来讲,他们可以买进前期业绩优秀的基金,而卖出前期业绩差的基金,来获取超额收益,投资者不必耗费大量的资金和时间去评价和选择基金经理。本文就基金业绩持续性的研究理论方法进行阐述,并对我国投资基金作实证分析。  相似文献   
56.
Backtesting Value-at-Risk: A Duration-Based Approach   总被引:2,自引:0,他引:2  
Financial risk model evaluation or backtesting is a key partof the internal model's approach to market risk management aslaid out by the Basle Committee on Banking Supervision. However,existing backtesting methods have relatively low power in realisticsmall sample settings. Our contribution is the exploration ofnew tools for backtesting based on the duration of days betweenthe violations of the Value-at-Risk. Our Monte Carlo resultsshow that in realistic situations, the new duration-based testshave considerably better power properties than the previouslysuggested tests.  相似文献   
57.
电子商务环境下的内部控制与风险管理   总被引:3,自引:0,他引:3  
会计职业人员对评估内部控制并实施风险管理的技能已熟知多年。这种经过时间检验并证明行之有效的经验和专业技能是会计职业产业独特影响的知识基础。随着电子商业的发展,尽管目前尚没有统一且标准的定义,但其发展对会计职业却提出了挑战。从某种意义上讲,企业的风险评估增加了很多新的内容,而与之相对应的内部控制也需要进行必要的调整,从而实行风险管理。本文拟就电子商务环境下的内容控制和风险 管理及其手段进行分析。  相似文献   
58.
59.
Nowadays, there still exist many problems in the research of the intangible assets evaluation theory, such as the division and isolation from others, weak support for the practice, etc. This paper puts forward a new system info which is to direct the practice in the socialist market economy and network society, The new system info breaks through the traditionally practical one, which is "evaluation aim value standard-evaluation method-- evaluation result". Furthermore, this system into could support the intangible assets evaluation to practice better than before and adapt to the new demands in socialist market economy environment and network society.  相似文献   
60.
A survey was conducted in Lilongwe city urban markets in Malawi, to assess the quality of cooking oil used for frying potato chips. Purposive sampling was performed to come up with respondents who were using vegetable oils. A stratified random sampling was used to select the 32 informal food processors who were interviewed using a structured questionnaire. Oil samples were collected from the most commonly used brand of oil. Fifteen respondents were selected and these were divided into three categories of five: those who were not reusing the oil, those who were reusing the oil and those who were preparing potato chips and chicken in the same oil, for chemical analysis. The preliminary results showed that while the majority (59.4%) of the informal food processors discarded the oil after 1 day, 3.1% discarded it after 4 days and another 12.5% after 3 days. A larger proportion of the respondents (40.6%) used the leftover oils at home, 37.5% kept it in oil bottles, 3.1% kept it in plastic papers for reuse the following day. Also, most respondents (57%) indicated dark colour as the sign of oil deterioration, 29% discarded the oil after noticing foam formation while 8.2% and 6.1% said they discarded the oil after noticing a bad smell and food absorbing the oils respectively. A physical observation of the various oils showed that for most of the respondents (34%), the oils were dark brown in colour, in 22%, the oils were slightly dark brown and 16%, the oils were brown. Foam formation was noticed in 13% of the respondents. It was also noted that 91% of the respondents had not been trained or briefed of food quality and safety issues. A chemical analysis of the oils showed high values of free fatty acids (range, 0.84–1.4112 compared with 0.42 in the fresh oil) and peroxide values (range 14.7–16.6 compared with 9.0 in the fresh oil). It may be concluded that the oils being used by the informal food processors in Malawi are of poor quality and so the foods cooked in them may be a health hazard to the consumers and the processors themselves. Although this work in ongoing, it may be recommended at the outset that the health department of the city assemblies should inspect these oils for the good health of the consumers.  相似文献   
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