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41.
绿色小水电评价的作用、内容及标准分析 总被引:1,自引:0,他引:1
绿色小水电评价是从环境、社会、经济和安全四个方面,对处于运行阶段的小水电站进行评价,根据评价结果给予处于行业先进水平的小水电站以经济、政策或技术方面的激励.在分析国际水电环境认证制度、水电可持续性评估规范和我国相关技术标准的基础上,针对我国小水电行业存在的问题,提出通过实施技术评价和激励机制为核心的绿色小水电评价,从而发挥行业引导作用,促进实现小水电保护生态和改善民生的基本目标.本文分析了绿色小水电评价的含义和作用,从环境保护、社会发展、经济效益和安全运行四个方面分析了评价的主要内容,并且探讨了评价基线和标准阈值两个评价标准的关键问题 相似文献
42.
不同含水率下非饱和黄土K0固结特性试验 总被引:1,自引:0,他引:1
针对非饱和原状黄土进行了不同含水率下的恒荷重K0固结试验研究,分析了含水率对割线模量,应力应变特性及侧压力系数的影响。试验表明,在其他条件相同的情况下,割线模量随着荷载的施加逐渐减小,最终趋于稳定,达到稳定值时的割线模量随着含水率的增大而减小,且与含水率线性相关;含水率越大,静止侧压力系数K0增长速率越快,至土结构完全破坏,K0趋于稳定;不同含水率的K0值最终趋于稳定,且稳定值差异性较小;提出了考虑含水率因素的连续加载条件下K0固结过程的变形模型,为研究黄土地区K0固结过程中土体变形特性及路堤沉降提供参考。 相似文献
43.
针对平原水库围坝填筑压实度快速检测做了大量的"三点击实"和标准击实试验。分析了三点击实试验过程中减水情况及加、减水情况下试验方法的可行性及其数据合理性,和标准击实试验方法进行了比较,认为减水情况及加、减水情况下试验方法是可行的,在减水情况下最优含水率和填土含水率的差值一般在-3%~0,同时试验过程中土体减水率小于6%时,三点击实试验成果比较合理。用三点击实试验方法填筑土体压实度所用时间比标准击实试验的方法省6~8h,三点击实试验填筑土体压实度的方法针对土体特性差别较大的工程中适用性强。提出了减水情况下的三点击实试验步骤及试验过程中的注意事项。 相似文献
44.
Measures developed for the analysis of corporate diversification have become fundamental to a broad range of strategy research. This paper examines the content validity of the two most widely used continuous measures of related diversification—the related component of the entropy index and the concentric index—and raises fundamental questions about their validity as indicators of portfolio relatedness. These questions are not driven by the use of SIC data for estimation of the indexes; they involve validity problems intrinsic to the construction of the measures. The related component of entropy and the concentric index are sensitive to features of corporate portfolio composition that may not be directly linked to portfolio relatedness. These sensitivities can create important ambiguities in strategy research. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
45.
Bao DA-HSIEN Chien CHIN-CHEN Lee CHENG-FEW 《Review of Quantitative Finance and Accounting》1997,8(3):229-244
This study attempts to identify firm characteristics that explain the disparity between the information content of accounting earnings and stock prices. Granger's causality concept was employed to classify sample firms into four groups: price-leading firms, feedback-system firms, earnings-leading firms, and no-causation firms. The feedback-system firms were either combined with the no-causation firms or eliminated entirely to form three sample groups. The entire sample firms then were divided into two classes. The first is for estimation, and the second is for prediction. Results indicate that firm size, capital structure, R-square of regressing prices at time t against earnings at time t – 1, R-square of regressing earnings at time t against prices at time t – 1, and percentage of shares held by institutions are the significant explaining variables. The application of the coefficient estimates to the hold-out sample indicates that 76.2% of the firms can be correctly classified into the corresponding groups. These results were consistent with those from canonical discrimination and other multivariate statistical methods. 相似文献
46.
在建筑工程施工新技术推广与应用现状宏观分析的基础上,以“2004年建设部科技示范工程项目”大连开发区文化中心施工新技术应用与推广为实例,分析了如何结合工程实际采用新技术来提高工程科技含量、保证工程质量,并提出了一些措施和对策。 相似文献
47.
基于参与度理论与社交媒体特点定义消费者社交媒体参与度与它的四个维度:意识、产生情感、产生理性思考、认同。建立社交媒体广告内容分类标准,收集二手数据后使用方差模型分析品牌社交媒体广告内容对消费者社交媒体参与度的影响。结果显示社交媒体广告内容类型显著影响消费者社交媒体参与度,新产品内容效果最好,其次是促销、游戏/抽奖、社会责任内容。此研究结果不仅可丰富消费者行为视角的品牌社交媒体广告相关理论研究,也可为品牌设计社交媒体广告内容营销提供管理建议。 相似文献
48.
Researchers and brand managers have limited understanding of the effects social media communication has on how consumers perceive brands. We investigated 504 Facebook users in order to observe the impact of firm-created and user-generated (UG) social media communication on brand equity (BE), brand attitude (BA) and purchase intention (PI) by using a standardized online survey throughout Poland. To test the conceptual model, we analyzed 60 brands across three different industries: non-alcoholic beverages, clothing and mobile network operators. When analyzing the data, we applied the structural equation modeling technique to both investigate the interplay of firm-created and user-generated social media communication and examine industry-specific differences. The results of the empirical studies showed that user-generated social media communication had a positive influence on both brand equity and brand attitude, whereas firm-created social media communication affected only brand attitude. Both brand equity and brand attitude were shown to have a positive influence on purchase intention. In addition, we assessed measurement invariance using a multi-group structural modeling equation. The findings revealed that the proposed measurement model was invariant across the researched industries. However, structural path differences were detected across the models. 相似文献
49.
The purpose of this study is to investigate the impacts of comparative claims across search and experience product types. Data was obtained from 159 Taiwanese college students. Results reveal that comparative claims used in blogs (compared to those in print ads) produce lower counterarguments and consumers more easily accept claims made on a blog. Comparative claims lead to higher brand attitude and purchase intention for search products on the blog; however, noncomparative ads lead to higher brand attitude and purchase intention for experience products on the blog. For both search and experience products, there is no significant difference. 相似文献
50.