全文获取类型
收费全文 | 26743篇 |
免费 | 1596篇 |
国内免费 | 806篇 |
专业分类
财政金融 | 1287篇 |
工业经济 | 1153篇 |
计划管理 | 5439篇 |
经济学 | 3426篇 |
综合类 | 2130篇 |
运输经济 | 365篇 |
旅游经济 | 724篇 |
贸易经济 | 2773篇 |
农业经济 | 1955篇 |
经济概况 | 2366篇 |
水利工程 | 7527篇 |
出版年
2024年 | 102篇 |
2023年 | 393篇 |
2022年 | 528篇 |
2021年 | 714篇 |
2020年 | 909篇 |
2019年 | 775篇 |
2018年 | 778篇 |
2017年 | 990篇 |
2016年 | 993篇 |
2015年 | 1017篇 |
2014年 | 1991篇 |
2013年 | 2305篇 |
2012年 | 2174篇 |
2011年 | 2628篇 |
2010年 | 1845篇 |
2009年 | 1684篇 |
2008年 | 1795篇 |
2007年 | 1648篇 |
2006年 | 1371篇 |
2005年 | 1117篇 |
2004年 | 810篇 |
2003年 | 563篇 |
2002年 | 389篇 |
2001年 | 322篇 |
2000年 | 272篇 |
1999年 | 175篇 |
1998年 | 158篇 |
1997年 | 122篇 |
1996年 | 113篇 |
1995年 | 100篇 |
1994年 | 92篇 |
1993年 | 59篇 |
1992年 | 62篇 |
1991年 | 34篇 |
1990年 | 13篇 |
1989年 | 21篇 |
1988年 | 7篇 |
1987年 | 10篇 |
1986年 | 9篇 |
1985年 | 13篇 |
1984年 | 15篇 |
1983年 | 16篇 |
1982年 | 8篇 |
1981年 | 1篇 |
1980年 | 2篇 |
1979年 | 2篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
61.
62.
Most decision making research in management accounting remains focused on cost information in a production context. Little is known on the relevance of customer profifitability analysis (CuPA) reports, which more accurately reflect revenue and marketing support variations acrosscustomers, for marketing decisions. This study uses an experimental design to examine the impact of such reports on resource allocation decisions (that affect the firm's profits) in marketing environments varying in complexity. The main result of the experiment suggests that the value of CuPA reports depends on the complexity of the marketing setting. Only in a highly complex marketing setting do they enhance resource allocation decisions and resultant firm profitability. Conversely, in the simple marketing environment, decision makers can combine their traditional volume-based cost data with other available types of feedback to perform as well as under a more accurate CuPA report. These findings on complexity contrast with those of a prior study in a production context ( Gupta and King, 1997 ). It is argued that improvements in the current research design, in the form of regularly updated profitability reports and concerning accuracy, increase the relevance of CuPA reports in a complex marketing setting. 相似文献
63.
阜新市细河改造工程由四座橡胶坝和两岸防洪大堤组成,由于堤(坝)基第四系冲洪积层广泛发育,存在渗漏同题。合理选择施工处理方案,是工程成功的关键。作者根据场区不同的地质条件环境条件采取有针对性的不同处理方案,既解决了防渗问题又缩短了施工工期,降低工程造价,取得了很好的经济效益和社会效益。 相似文献
64.
强度储备法在飞来峡土坝稳定性分析中的应用 总被引:1,自引:0,他引:1
强度储备法抓住影响坝体稳定因素中最关键的强度指标,通过研究不同强度参数所对应的破坏区域的演变关系,分析坝体的稳定性和潜存的破坏机理,在混凝土坝和岩体结构的稳定分析中得到了普遍应用。但将强度储备法应用于土坝稳定性分析中属首次,以飞来峡水利枢纽土坝为例,采用二维有限元强度储备法对其稳定安全系数进行了计算分析,研究了边坡的失稳破坏机理,对安全性进行了评价,为运行管理提出了一些有益的参考意见。 相似文献
65.
文中通过对山西省水文数据库建设的回顾,分析了数据库的库表结构及相关内容,并对今后数据库的建设工作提出了建议和展望。 相似文献
66.
An Interval Fuzzy Multiobjective Watershed Management Model for the Lake Qionghai Watershed, China 总被引:4,自引:0,他引:4
Lijing Wang Wei Meng Huaicheng Guo Zhenxing Zhang Yong Liu Yingying Fan 《Water Resources Management》2006,20(5):701-721
Integrated watershed management is required to ensure the reasonable use of resources and reconcile interactions among natural and human systems. In the present study, an interval fuzzy multiobjective programming (IFMOP) method was used to solve an integrated watershed management problem. Based on system analysis, an IFMOP model suitable for a lake watershed system {IFMOPLWS} was developed and applied to the Lake Qionghai watershed in China. Scenario analysis and an interactive approach were used in the solution process. In this manner, various system components were incorporated into one framework for holistic consideration and optimization. Integrality and uncertainty, as well as the multiobjective and dynamic characteristics of the watershed system, were well addressed. Using two scenarios, two planning schemes were generated. Agriculture, tourism, macroeconomics, cropland use, water supply, forest coverage, soil erosion, and water pollution were fully interpreted and compared to identify a preferable planning alternative for local agencies. This study showed that the IFMOPLWS is a powerful tool for integrated watershed management planning and can provide a solid base for sustainable watershed management. 相似文献
67.
混凝土面板堆石坝是引子渡水电站的主要水工建筑物,在大坝坝体填筑及混凝土面板的施工过程中,通过室内及现场试验确定了质量控制参数,并采取了必要的质量控制措施,从而保证了工程质量。本文主要对质量控制情况及检测成果作简要介绍。 相似文献
68.
Coupling GIS with Hydrologic and Hydraulic Flood Modelling 总被引:6,自引:1,他引:5
Nunes Correia Francisco Castro Rego Filipe Da Grača Saraiva Maria Ramos Isabel 《Water Resources Management》1998,12(3):229-249
Geographic Information Systems (GIS) have been recognised as a powerful means to integrate and analyse data from various sources in the context of comprehensive floodplain management. As part of this comprehensive approach to floodplain management, it is very important to be able to predict the consequences of different scenarios in terms of flooded areas and associated risk. Hydrologic and hydraulic modelling plays a crucial role and there is much to gain in incorporating these modelling capabilities in GIS. This is still a rather complex task and research is being done on the full integration of these models. Interfacing between these models and GIS may be a very efficient way of overcoming the difficulties and getting very good results in terms of engineering practice. This paper presents results based on the use of Intergraph GIS coupled with Idrisi GIS. Using these two systems substantially increased the flexibility of using GIS as a tool for flood studies. A lumped (XSRAIN) and a distributed (OMEGA) hydrologic models were used to simulate flood hydrographs. The well known HEC-2 Hydraulic model was used to compute flooded areas. These models were applied in the Livramento catchment with very good results. The computation of flooded areas for different flood scenarios, and its representation in GIS, can be used in the assessment of affected property and associated damages. This is a very useful GIS-based approach to floodplain management. 相似文献
69.
氧化微晶蜡生产的技术经济分析 总被引:1,自引:1,他引:0
简要介绍了微晶蜡氧化工艺及氧化微晶蜡产品特点,并对其进行了初步经济评价,同时对氧化微晶蜡下游产品如防锈蜡,乳化蜡及塑料润滑用蜡等进行了市场分析,最后给出了氧化微晶蜡下游产品生产的若干建议。 相似文献
70.
企业每一项经营决策都应该进行成本效益分析,市场竞争中可以根据本企业的成本曲线和需求曲线,预测出竞争策略实施后对内部成本和外部需求可能产生的影响,从而计算出某项决策的经济效果。 相似文献