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901.
Traditional risk assessments, including those involving the United States Department of Energy (USDOE), are often criticized for producing useless or noncredible management responses because they did not meaningfully involve the public. The first step to involve the public is to identify appropriate active participants (stakeholders). This study was done to understand the processes used to identify stakeholders to serve on advisory boards established at the two largest remediation sites in the United States: the Hanford Nuclear Reservation in Washington state and the Savannah River Site in South Carolina. The Hanford stakeholder identification process produced an interest-based board whereas the Savannah River Site strategy produced population-based representation. The basic goals of the stakeholder advisory groups were similar. However, different processes were used to identify the participants for the groups in part because of distinctly different social and cultural conditions in the areas affected by the operations of the two facilities, and in part because of the different level of trust of the USDOE and their contractors at Hanford compared with Savannah River. The discussion analyzes their different needs and potential for successful citizen participation.  相似文献   
902.
Most public health risk assessments assume and combine a series of average, conservative, and worst-case values to derive a conservative point estimate of risk. This procedure has major limitations. This paper demonstrates a new methodology for extended uncertainty analyses in public health risk assessments using Monte Carlo techniques. The extended method begins as do some conventional methods--with the preparation of a spreadsheet to estimate exposure and risk. This method, however, continues by modeling key inputs as random variables described by probability density functions (PDFs). Overall, the technique provides a quantitative way to estimate the probability distributions for exposure and health risks within the validity of the model used. As an example, this paper presents a simplified case study for children playing in soils contaminated with benzene and benzo(a)pyrene (BaP).  相似文献   
903.
This study replicates, refines, cross-validates and simplifies a scheme of operationalization and measurement of environmental dimensions proposed by Dess and Beard (1984). Employing a sample of 60 industries and data over a 16-year period, this study found considerable support for the viability of the three dimensions of munificence, dynamism and complexity. The data intensive and computationally complex operationalization scheme was simplified using a discriminant analysis approach and the discriminant functions were cross-validated using an alternate data set.  相似文献   
904.
Multi-criteria inventory classification groups inventory items into classes, each of which is managed by a specific re-order policy according to its priority. However, the tasks of inventory classification and control are not carried out jointly if the classification criteria and the classification approach are not robustly established from an inventory-cost perspective. Exhaustive simulations at the single item level of the inventory system would directly solve this issue by searching for the best re-order policy per item, thus achieving the subsequent optimal classification without resorting to any multi-criteria classification method. However, this would be very time-consuming in real settings, where a large number of items need to be managed simultaneously.

In this article, a reduction in simulation effort is achieved by extracting from the population of items a sample on which to perform an exhaustive search of best re-order policies per item; the lowest cost classification of in-sample items is, therefore, achieved. Then, in line with the increasing need for ICT tools in the production management of Industry 4.0 systems, supervised classifiers from the machine learning research field (i.e. support vector machines with a Gaussian kernel and deep neural networks) are trained on these in-sample items to learn to classify the out-of-sample items solely based on the values they show on the features (i.e. classification criteria). The inventory system adopted here is suitable for intermittent demands, but it may also suit non-intermittent demands, thus providing great flexibility. The experimental analysis of two large datasets showed an excellent accuracy, which suggests that machine learning classifiers could be implemented in advanced inventory classification systems.  相似文献   

905.
The purpose of this paper is to examine a type of resource allocation problem arising in the context of research and development activities. The particular problem analyzed involves scheduling a group of projects in such a way that total cost is minimized while several precedence relations are satisfied and specific completion times are maintained. The primary difficulty results from the existence of commonalities that allow the successful completion of a particular project to be applied to several different purposes. A solution approach is developed which combines a one-pass network algorithm to deal with the precedence and time restrictions and a dynamic programming procedure to allocate the resources to each project.  相似文献   
906.
This article is a follow-up to an interview with Charles Dwyer, PhD, which appeared in the 1999 March/April issue of The Physician Executive. He described how physician executives can change the perceptions of today's beleaguered physicians and help them cope with change. We then asked him for some hands-on strategies to deal with physician anger, fear, and resentment. After much contemplation on providing a list of "fixes" that will restore each of us to a state of greater satisfaction, Dr. Dwyer concludes that there are no generalizable solutions because there are too many variables that come into play in each organization, individual, or group. Attending to the self can provide both individual rescue from these turbulent times and the best hope for changes in the system from which patients and health care providers can benefit. If physicians are to regain their power and maintain, or even improve, their quality of life, clearly changes are called for. And these are changes that require persistent effort and uncomfortable adjustments.  相似文献   
907.
908.
The patterns of family formation and fertility behavior of Turkish and Moroccan women in Belgium are changing rapidly. The census data (1991) indicate a fertility decline. The reasons are changes in the nuptiality patterns, contraceptive behavior, and migratory flows. The changes are not identical in both communities. Young cohorts postpone their marriage, but this is most prominent among Moroccan women. On the other hand, young Turkish women have a clear preference for smaller families. The changes also differentiate according to migrant "generation" and level of education. The changes are not restricted to Belgium but are also observed in the countries of origin.  相似文献   
909.
Throughout its history, "ideology" (the concept and theory) served as social science's foil, an opposing standard against which it defined its own knowledge-as-truth. As social science since mid-century has undergone changes in its idea of itself and its methods of inquiry, the theory of ideology has served as register, visably recording these changes. Works by the structuralists and poststructuralists, especially Althusser and Foucault, forced upon social theorists a profound rethinking of power and its operations and moved "ideology" away from the theory of false consciousness towards a view of ideology as cultural practice. For some, ideology theory is obsolete (due to its classical roots as "false consciousness") or redundant (due to its links to "culture"). Despite the merits of these arguments, a provisional argument on behalf of ideology theory is offered.

Marxism, after drawing us to it as the moon draws the tides, after transforming all our ideas, after liquidating the categories of our bourgeois thought, abruptly left us stranded.
—Jean-Paul Sartre  相似文献   
910.
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