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61.
62.
Laurence J. O'Toole Jr. Chilik Yu James Cooley Gail Cowie Susan Crow Terry DeMeo Stephanie Herbert 《政策研究杂志》1997,25(1):11-26
Relatively little is known about the possibilities and limitations of voluntary public programs. The so-called 33/50 Program for reducing releases of certain toxic chemicals into the environment provides a useful instance for examination. In an investigation of toxics-reduction outcomes, with states as units of analysis, economic and policy variables help to explain the results. In particular, channels and approaches used In communicating policy intentions are related to outcomes. Voluntary programs can make a difference, but the details of execution, including the extent and nature of field efforts, influence outcomes. 相似文献
63.
64.
Jeffrey James 《Development and change》1993,24(3):405-437
This article is concerned with the impact of new technologies - especially, but not entirely, those that are related to microelectronics - on employment and labour markets in developing countries. Taking the form of a literature survey it looks at those impacts that have already occurred as well as effects that seem likely to occur in the future. Both sets of issues are addressed within an analytical framework that views the impact of technical change as the end result of a process which begins with the generation and proceeds via the diffusion of new technologies. The need for so broad an approach is shown to stem from the multiplicity of ways in which the generation and diffusion of new technologies influence each other and condition the ultimate impact of these technologies on employment and labour markets. Because many such mechanisms have not yet received much attention in the literature, there appears to be substantial scope for further research. 相似文献
65.
This paper extends a compartmental epidemiological model for HIV transmission and AIDS incidence to include hierarchical and expansion spatial diffusion. An implication of the resultant model is that hierarchical diffusion causes the large infection growth rates of densely populated areas at the top of the central places hierarchy to “chain” down and dominate small local growth rates during the exponential-growth phase of the epidemic. Also, hierarchical diffusion causes a high transient growth rate in the first few years of a local epidemic. The spatial compartmental model fits observed AIDS incidence spatial diffusion patterns in Ohio reasonably well. 相似文献
66.
This paper develops a nested family of market interaction models for the general case of spatial or aspatial goods. Market structure effects are identified in the form of intraregional and extraregional competition. The competing destinations and competing central place models are shown to be special cases of the general modeling framework. An empirical example, using survey data collected from Chicago-area Management and Public Relations (SIC 874) firms, illustrates how the family of models may be used to identify market structure. 相似文献
67.
James A. Bill 《Iranian studies》1993,26(3-4):403-406
68.
The US. and France have adopted contrasting models of motor fuel tax and highway finance policy. Fuel tax revenues are dedicated to state and federal highway funds in America, keeping taxes quite low, but preventing them from contributing to the general treasury. French motor fuel taxes are higher and make up nearly 11 percent of the central government's general revenues, excluding social security contributions. French highway finance relies heavily on tolls. Pressure from the US. federal deficit has reduced the highway trust fund's ability to protect highway spending from budgetary competition. Political and procedural changes in Congress make it likely that the U.S.will move away from exclusive dedication of motor fuel taxes. 相似文献
69.
Andrew Pike 《European Planning Studies》1993,1(3):319-349
This paper examines the impact of the creation of the Single European Market (SEM) by exploring the restructuring of the automotive production sector in Europe and its effect upon the older industrial regions of the UK. The paper is divided into four sections. Firstly, the importance of automotive production as a key sector in understanding the true impact of restructuring for the SEM is outlined. Secondly, the directions and outcomes of restructuring in the sector are detailed. Thirdly, the specific impact of these changes on automotive production and the older peripheral regions of the UK is considered. Finally, some conclusions and future directions for policy are discussed in relation to the true shape and form of ‘the new Europe’. The paper argues that the SEM will reinforce and deepen the pervasive and divergent effects of industrial restructuring within its boundaries due to economic relations from without. 相似文献
70.
Kevin D. Ingram Kenneth E. Daugherty James L. Marshall 《Journal of archaeological science》1993,20(6)
Several samples of pyramids from Giza were obtained. The samples were analysed by scanning electron microscopy, electron diffraction by X-rays, powder X-ray diffraction, inductively coupled plasmography, Fourier-transform infrared spectroscopy and other techniques. Some scientists who have recently studied the pyramids have suggested that the pyramids were poured into place, stone by stone. The prevailing theory among Egyptologists is, of course, that the pyramids were built from blocks of natural stone. All of the results obtained during this study directly support the concept that the pyramids are made of limestone and are not cementitious in nature. 相似文献