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861.
A number of highly publicized, controversial lapses in social responsibility within global supply chains have forced managers and scholars to reexamine long‐held perspectives on supplier selection. Extending Carter and Jennings’ department‐level study of purchasing social responsibility, our research assesses the role of supply managers’ ethical intentions and three key antecedents that drive socially responsible supplier selection. Comparing evidence from firms operating in China, the United States, and the United Arab Emirates, we identify three key drivers of supply managers’ ethical intentions and examine both their direct and indirect impacts on socially responsible supplier selection. We find differential support for the predictor relationships on supply manager ethical intentions across national contexts and mediated versus nonmediated models. These observations bear important implications for firms conducting global supply management. 相似文献
862.
Extended enterprises face many challenges in managing the product quality of their suppliers. Consequently characterizing the quality risk posed by value‐chain partners has become increasingly important. There have been several recent efforts to develop frameworks for rating the quality risk posed by suppliers. We develop an analytical model to examine the impact of such quality ratings on suppliers, manufacturers, and social welfare. While it might seem that quality ratings would benefit high‐quality suppliers and hurt low‐quality suppliers, we show that this is not always the case. We find that such quality ratings can hurt both types of suppliers or benefit both, depending on the market conditions. We also find that quality ratings do not always benefit the most demanding manufacturers who desire high‐quality suppliers. Finally, we find that social welfare is not always improved by risk ratings. These results suggest that public policy initiatives addressing risk ratings must be carefully considered. 相似文献
863.
864.
865.
The matching identification problem (MIP) is a combinatoric search problem related to the fields of learning from examples, boolean functions, and knowledge acquisition. The MIP involves identifying a single “goal” item from a large set of items. Because there is commonly a cost associated with evaluating each guess, the goal item should be identified in as few guesses as possible. As in most search problems, the items have a similar structure, which allows an evaluation of each guessed item. In other words, each guessed item elicits partial information about the goal item, i.e. how similar the guess is to the goal. With this information the goal is more quickly identified.The unordered MIP has been studied by Mehrez and Steinberg (ORSA J. Comput. 7 (1995) 211) in which they proposed two different types of algorithms. The purpose of the present paper is to suggest an improved Spanning Heuristic algorithm. Its improvement increases as the problem size increases. Further results and comparisons are derived for the unordered and ordered cases.This research shows that when the search space is very large, it is better to inquire from items that are known not to be the goal (they have been ruled out by previous guesses), for the purpose of acquiring more information about the goal. As the search space is narrowed, it is better to guess items that have not been ruled out. 相似文献
866.
The career-plateau as challenge to enterprises, employees and consultantsThe authors intend to link life-span-psychology to career-research in order to make understand the phenomenon of career-plateau and how individuals and organisations can deal with it. People take stock in the middle of their lives and assess their personal or professional targets. This process often relates to a personal crisis, especially when the success rate of a job is an important part of the self-concept and hierarchical development has stopped simultaneously. Nevertheless, the desire for a career continues to exist. On top of that what makes it even harder is that the individual has to work at least 20 more years because of demographic reasons. We assume that the way how to manage this crisis has a big influence on performance motivation and that life-span-orientated management development can help the individual to overcome the crisis or even prevent it. 相似文献
867.
The purpose of this study is to revise and revalidate the End‐User Computing Satisfaction (EUCS) instrument to measure satisfaction with a Web site from a usability perspective. This study is especially important given the increased significance of the Web and the uniqueness of the Web as a computing environment. A total of 176 students participated in a lab simulation that involved a usability evaluation of the Lands' End Web site ( http://www.landsend.com ). Students were asked to complete a set of tasks, record their answers, and then complete the EUCS instrument. Confirmatory factor analysis and invariance analyses were conducted to test the reliability, validity, and generalizability of the revised EUCS. The results show that the EUCS is a valid and robust instrument in the Web environment but that one of the subfactors, timeliness, will need further refinement in the future. Usability practitioners can use the EUCS to measure end‐user satisfaction with a Web site and use the feedback for improving Web‐site design. We describe a case study of an actual usability application that utilized the revised EUCS effectively to support the design of building supply Web sites involving two types of end users, homeowners and contractors. We also propose a typology that researchers can use as a starting point to judge when it is necessary to revalidate an instrument like the EUCS. Finally, we discuss the limitations of our study and present avenues for future research. 相似文献
868.
Uday S. Rao Jayashankar M. Swaminathan Jun Zhang 《Production and Operations Management》2005,14(4):400-412
Recently, innovation‐oriented firms have been competing along dimensions other than price, lead time being one such dimension. Increasingly, customers are favoring lead time guarantees as a means to hedge supply chain risks. For a make‐to‐order environment, we explicitly model the impact of a lead time guarantee on customer demands and production planning. We study how a firm can integrate demand and production decisions to optimize expected profits by quoting a uniform guaranteed maximum lead time to all customers. Our analysis highlights the increasing importance of lead time for customers, as well as the tradeoffs in achieving a proper balance between revenue and cost drivers associated with lead‐time guarantees. We show that the optimal lead time has a closed‐form solution with a newsvendor‐like structure. We prove comparative statics results for the change in optimal lead time with changes in capacity and cost parameters and illustrate the insights using numerical experimentation. 相似文献
869.
Stanislav?BusyginEmail author Oleg?A.?Prokopyev Panos?M.?Pardalos 《Journal of Combinatorial Optimization》2005,10(1):7-21
Biclustering consists in simultaneous partitioning of the set of samples and the set of their attributes (features) into subsets (classes). Samples and features classified together are supposed to have a high relevance to each other which can be observed by intensity of their expressions. We define the notion of consistency for biclustering using interrelation between centroids of sample and feature classes. We prove that consistent biclustering implies separability of the classes by convex cones. While previous works on biclustering concentrated on unsupervised learning and did not consider employing a training set, whose classification is given, we propose a model for supervised biclustering, whose consistency is achieved by feature selection. The developed model involves solution of a fractional 0–1 programming problem. Preliminary computational results on microarray data mining problems are reported.This research work was partially supported by NSF, NIH and AirForce grants. 相似文献
870.
Tolerable or Acceptable: A Comparison of Risk Regulation in the United Kingdom and in the Netherlands 总被引:1,自引:0,他引:1
B. J. M. Ale 《Risk analysis》2005,25(2):231-241
In managing major accident hazards in industry risk, both the United Kingdom and the Netherlands use quantitative risk analysis and quantified risk criteria. These should be understood in the historical, legal, and political context in which they were drawn up. Even when criteria are numerically the same they do not necessarily mean the same thing. The legal and historical context differs widely between the two countries. Nevertheless, it is surprising that the final results in terms of land use and levels of risk are very similar. 相似文献