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51.
In performance evaluations, data without explicit inputs (such as index data, pure output data) are widely used. To directly use such data, this paper presents a study on building DEA models without explicit inputs, so-called DEA-WEI models, which are applicable to the evaluation applications where inputs are not directly considered. We provide an axiom foundation of these kinds of models, and further discuss how to incorporate value judgments of decision makers into these DEA-WEI models. Several such models are derived. Finally, applications of the DEA-WEI models are presented. 相似文献
52.
Foreign direct investment (FDI) has been known to generate positive externalities to increase the productivity and competitiveness of domestic industries through knowledge and technology spillover. This study focuses on the indirect effect of FDI by investigating whether FDI intensity benefits local firms by enhancing the local intellectual property rights (IPR) environment. We argue that due to the inadequate IPR environment in emerging economies, local firms' intangible resources investment can be negatively related to firm performance. Further, we suggest that FDI intensity can improve the local IPR environment, thereby enhancing the appropriability of local firms' intangible resources investment. We find empirical evidence to support our arguments by examining 70 semiconductor firms in China from 1999 to 2006, and we discuss the theoretical and practical implications of the impact of FDI intensity on the local IPR environment. 相似文献
53.
54.
This paper investigates whether an expectations gap exists in the control, strategic and resource provision roles that independent directors play in the corporate governance of listed Chinese firms and the factors that affect their performance of these roles. For this purpose, we interviewed Chinese executive directors, independent directors, institutional investors and stock exchange regulators. We find a performance gap but no reasonableness gap with respect to the control and strategic roles. The results suggest that the performance gap may be attributed to such factors as the ill‐defined roles, independent directors' limited amount of time commitment and their lack of competence and objectivity. Interestingly, there is disagreement over the protection of minority interest as the objective of the control role. We find no consensus on the desirability, reasonableness and effectiveness of independent directors' resource provision role, perhaps because of a pejorative interpretation of this role as an exercise of guanxi. 相似文献
55.
Prediction of natural disasters and their consequences is difficult due to the uncertainties and complexity of multiple related factors. This article explores the use of domain knowledge and spatial data to construct a Bayesian network (BN) that facilitates the integration of multiple factors and quantification of uncertainties within a consistent system for assessment of catastrophic risk. A BN is chosen due to its advantages such as merging multiple source data and domain knowledge in a consistent system, learning from the data set, inference with missing data, and support of decision making. A key advantage of our methodology is the combination of domain knowledge and learning from the data to construct a robust network. To improve the assessment, we employ spatial data analysis and data mining to extend the training data set, select risk factors, and fine‐tune the network. Another major advantage of our methodology is the integration of an optimal discretizer, informative feature selector, learners, search strategies for local topologies, and Bayesian model averaging. These techniques all contribute to a robust prediction of risk probability of natural disasters. In the flood disaster's study, our methodology achieved a better probability of detection of high risk, a better precision, and a better ROC area compared with other methods, using both cross‐validation and prediction of catastrophic risk based on historic data. Our results suggest that BN is a good alternative for risk assessment and as a decision tool in the management of catastrophic risk. 相似文献
56.
Input‐output analysis is frequently used in studies of large‐scale weather‐related (e.g., Hurricanes and flooding) disruption of a regional economy. The economy after a sudden catastrophe shows a multitude of imbalances with respect to demand and production and may take months or years to recover. However, there is no consensus about how the economy recovers. This article presents a theoretical route map for imbalanced economic recovery called dynamic inequalities. Subsequently, it is applied to a hypothetical postdisaster economic scenario of flooding in London around the year 2020 to assess the influence of future shocks to a regional economy and suggest adaptation measures. Economic projections are produced by a macro econometric model and used as baseline conditions. The results suggest that London's economy would recover over approximately 70 months by applying a proportional rationing scheme under the assumption of initial 50% labor loss (with full recovery in six months), 40% initial loss to service sectors, and 10–30% initial loss to other sectors. The results also suggest that imbalance will be the norm during the postdisaster period of economic recovery even though balance may occur temporarily. Model sensitivity analysis suggests that a proportional rationing scheme may be an effective strategy to apply during postdisaster economic reconstruction, and that policies in transportation recovery and in health care are essential for effective postdisaster economic recovery. 相似文献
57.
Given a graph G=(V,E) with node weight w:V→R
+ and a subset S⊆V, find a minimum total weight tree interconnecting all nodes in S. This is the node-weighted Steiner tree problem which will be studied in this paper. In general, this problem is NP-hard
and cannot be approximated by a polynomial time algorithm with performance ratio aln n for any 0<a<1 unless NP⊆DTIME(n
O(log n)), where n is the number of nodes in s. In this paper, we are the first to show that even though for unit disk graphs, the problem is still NP-hard and it has a
polynomial time constant approximation. We present a 2.5ρ-approximation where ρ is the best known performance ratio for polynomial time approximation of classical Steiner minimum tree problem in graphs.
As a corollary, we obtain that there is a polynomial time (9.875+ε)-approximation algorithm for minimum weight connected dominating set in unit disk graphs, and also there is a polynomial
time (4.875+ε)-approximation algorithm for minimum weight connected vertex cover in unit disk graphs. 相似文献
58.
现代企业制度的内部会计控制问题探讨 总被引:1,自引:0,他引:1
现代企业内部会计控制是社会经济发展到一定阶段的产物,是随着企业不断加强内部管理的需要而发展起来的.随着经济全球化的到来,建立和完善符合现代企业制度的内部会计控制制度已成为我国企业的当务之急.只有通过内部会计控制的变革和创新,才能使企业实现可持续发展.本文在认识现代企业制度下内部会计控制的重要性的基础上,分析了我国企业在建立和完善现代企业制度过程中内部会计控制方面存在的问题,提出了现代企业制度下加强和完善企业内部会计控制制度的对策. 相似文献
59.
One of the most notorious network design problems is the Quadratic Assignment Problem (QAP). We develop an heuristic algorithm for QAPs along with an M/G/C/C state dependent queueing model for capturing congestion in the traffic system interconnecting the nodes in the network. Computational results are also presented. 相似文献
60.
We present two experiments investigating the role of emotions concerning technological and natural hazards. In the first experiment, technological hazards aroused stronger emotions, and were considered to be riskier than natural hazards. No differences were found between the texts versus audio presentations. However, the presence of pictures aroused stronger emotions and increased the perceived risk. Emotions play a mediating role between hazard types and perceived risk, as well as between pictures and perceived risk. The second experiment adopted real‐world materials from webpages and TV. Emotions again play a mediating role between pictorial information and risk perception. Moreover, specific emotions were found to be associated with different types of action tendencies. For example, loss‐based emotions (e.g., fear, regret) tend to lead to prevention strategies, whereas ethical emotions (e.g., anger) lead to aggressive behavior. We also find that loss‐based emotions in the technical hazard scenario trigger more coping strategies (from prevention to retaliation) than in the natural hazard scenario. 相似文献