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81.
The simulation problem is one of the most commonly used formats in computer-assisted instruction (CAI). In medical education, a patient simulation problem is known as a patient management problem (PMP). A number of computerized PMP systems are currently available. However, to date, there is no record of PMP systems having been developed using artificial intelligence. This is noteworthy since artificial intelligence techniques could help in the generation of more effective and intelligent instructional systems.

This paper analyzes and evaluates existing instructional simulation software in clinical medicine in terms of effective educational design attributes. Components of effective PMP systems thus identified are incorporated into a computerized instructional system which uses artificial intelligence techniques for teaching problem-solving and diagnostic skills to undergraduate medical students.  相似文献   

82.
Abstract . The concept of “self-efficacy” is used to test the hypothesis that the negative self-concept of welfare recipients coniributes to long term psychological and material dependency on such assistance. Self-efficacy focuses on the extent to which people are able to produce and regulate events in their lives and is associated with self-imposed performance expectations. The extent to which the minority status which Blacks occupy in this society decreases self efficacy relative to Whites is examined, using information generated from structured interviews with 290 low income Black and White women. Operationalizing the concept of self-efficacy with appropriate controls for socioeconomic status, family composition and other factors results in finding no racial differences in sense of self-efficacy between Black and White women. Observed differences in patterns of receipt of public assistance are found to be more directly related to the persistence of structural barriers to upward mobility that have differential impacts on Blacks and Whites. Long term receipt of public assistance is found to adversely affect both self-worth and work orientation/perceived efficacy for all women.  相似文献   
83.
Polyhedral combinatorics is a subarea of combinatorial optimization of increasing practical importance. It deals with the application of the theory of linear systems and linear algebra to combinatorial problems. The paper is not intended as a survey on polyhedral combinatorics but it reviews some of the main concepts and proof techniques.  相似文献   
84.
Distribution-free tests for comparing several treatments with a control   总被引:1,自引:0,他引:1  
Abstract  In this paper we propose distribution-free treatments versus control tests for the one- and two-way classifications. The null distribution properties are shown to be equivalent to those of well-known statistics for which critical values have been extensively tabled. Asymptotic relative efficiencies with respect to corresponding normal theory competitors are derived and optimal designs for the allocation of experimental units to the treatments and control are obtained.  相似文献   
85.
Summary The problem of estimating the slope of a linear relationship between two jointly normally distributed random variables is considered when outliers may occur in the explanatory variable. It will be studied as a special case of an errors-in-variables problem where the explanatory variable is measured which a nonnormally distributed error. In this more general model and under certain conditions a consistent estimator can be given with a normal limiting distribution. Applications to cases of outliers in the explanatory variable will be presented.  相似文献   
86.
The purpose of this study was to (a) compare the occupational sex stereotypes of 366 college students with those reported by Shinar in 1975, and (b) examine the relationships between demographic, experiential, and attitudinal variables and these occupational sex stereotypes. The results indicated a significant difference in occupational ratings from Shinar's study, with females' perceptions shifting more than males' perceptions. In addition, subjects' gender, tenure with female managers, and attitudes toward women as managers, were shown to be significant predictors of occuptational ratings. The implications of these findings for both employees and managers are then discussed.  相似文献   
87.
There is an increasing realization, world‐wide and in Southern Africa, that conservation and development are compatible.

Because human communities in the less developed rural areas are dependent on a renewable group of resources, including soil, water and forests, it is imperative that land use systems that protect these resources are introduced.

The predominance of subsistence agriculture in these areas is the most difficult syndrome of under‐development. An overall rural development strategy is required that integrates human development with resources management Where the population carrying capacity of the land has already been exceeded, a process of rapid villagization/urbanization is required. Village/urban growth and agricultural development require a carefully co‐ordinated programme of land capability analysis and planning, as well as active investment in infrastructure and the introduction of appropriate technologies and institutions.  相似文献   

88.
The impact of the brain drain on the educational systems of the countries of origin is examined, with particular reference to governmental decisions concerning education subsidies and the market for educational services. Two hypothetical cases are considered, one in which governments increase expenditures for education in the presence of a widespread brain drain, the other in which they decrease such expenditures.  相似文献   
89.
Like sociology, development sociology is currently torn between several perspectives, each of which accentuates a completely different view of the discipline. The systems, conflict and humanist perspectives are providing dominant theoretical approaches in the search for an appropriate theory. It is maintained that the current theoretical controversy impedes the development of such a theory.

Systems theory corresponds with neo‐evolutionary development theories and these are largely influenced by the works of Talcott Parsons. Neo‐Marxist development theory, on the other hand, follows the general argument of conflict theory, the accent being on the dialectic relationship between development and underdevelopment. Development theory related to humanism is still in an embryonic stage.

A plea is made for an attempt to design a Weberian‐based orientation which will embrace the current perspectives in order to develop a workable alternative for Southern Africa.  相似文献   

90.
Summary So far, the labour market has not received any special attention from macro-econometric model builders. In this article an attempt has been made to describe the labour market in detail, paying attention to such important phenomena as the friction between labour supply and demand, the heterogeneity of labour, the dependence of labour supply on the labour-market situation, the Phillips mechanism and the impact of real wages on labour demand. To make it suitable for policy simulations, the model has been extended to a complete macro-econometric model, taking account of the fact that both labour and capital limit the production possibilities.This paper summarises an extensive Dutch report on the construction of a model for the Netherlands labour market. The title of the original report is AMO-K: Een arbeidsmarktmodel met twee categorieën arbeid; (AMO-K, A labour-market model with two categories of labour) ; it was published by the Netherlands Economic Institute (NEI) in Rotterdam in the so-called Olive Series, 1982-2, pp. 403ff. Some details of the model presented in that report were changed after its publication; see G. den Broeder, AMO-K 81-12, Tussenrapport betreffende de verdere ontwikkeling van het arbeidsmarktmodel (Interim report on the further development of the labourmarket model), Rotterdam, September 1983. Since then, only minor changes have been carried through. The model reproduced in this paper is the modified version. The model was developed within the National Programme of Labour-Market Research (NPAO) (now defunct), the NPAO organisation having granted a commission to the NEI in Rotterdam.  相似文献   
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