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961.
Consider a life testing experiment in which n units are put on test, successive failure times are recorded, and the observation is terminated either at a specified number r of failures or a specified time T whichever is reached first. This mixture of type I and type II censoring schemes, called hybrid censoring, is of wide use. Under this censoring scheme and the assumption of an exponential life distribution, the distribution of the maximum likelihood estimator of the mean life 6 is derived. It is then used to construct an exact lower confidence bound for θ.  相似文献   
962.
Abstract

Purpose: To examine differences in site of death and costs of services by primary diagnosis for patients receiving home-based palliative care as compared to usual care at the end of life verity of illness, service use, and site of death.

Design and Methods: A nonequivalent group design was employed with 298 terminally ill patients diagnosed with cancer, CHF, or COPD enrolled. The treatment group received an interdisciplinary home-based palliative care program and the comparison group received usual Kaiser Permanente services. Data collected included patient demographics, se-

Results: Among all diseases, patients enrolled in palliative care were more likely to die at home. Enrollment in palliative care was significant associated with cost reductions for patients with cancer, COPD, and CHF. No significant difference was found between diagnostic groups in terms of magnitude of cost savings.

Implications: Provision of interdisciplinary home-based palliative care at end of life can effectively increase the likelihood of dying at home for patients with CHF, COPD, and cancer while realizing significant COSt savings.  相似文献   
963.
随着动漫产业的高速发展,其人才的培养也越来越受到业界和相关部门的高度重视。高校作为培养动漫人才的重要基地,是发展动漫产业与培养动漫人才的孵化器,文章针对高校培养动漫人才教育问题进行了讨论,并提出了若干对策建议。  相似文献   
964.
For the linear-exponential distribution with increasing hazard rate, exact and explicit expressions for means, product moments and percentage points of order statistics are obtained. Some recurrence relations for both single and product moments of order statistics are also derived. These recurrence relations would enable one to obtain all the higher order moments of order statistics for all sample sizes from those of the lower order  相似文献   
965.
This article analyses the processes of deviation from the Bismarckian welfare model in Italy, with a focus on social assistance. The sector was reformed in 2000, with new service provision functions being assigned to local institutions and the affirmation of a universalistic principle of access. However, an analysis of social expenditure data and a review of the process of implementation of the reform demonstrate that many local governments have been unable to enact the innovation and that a homogeneous nationwide trend of deviation from the Bismarckian tradition is absent. This absence is explained by looking both at the local institutional arrangements that have historically characterized the different Italian territories and at the present relationships among national, regional, and local governments.  相似文献   
966.
西安新农村建设规划的地域特色研究   总被引:1,自引:0,他引:1  
模糊的建设目标,非根植性的规划模式,急功近利的建设速度等致使西安新农村建设羁绊丛丛。针对西安新农村建设所存在的问题,结合西安新农村建设的现实基础,明确提出了西安新农村建设的目标体系,归纳总结了近年来西安新农村建设的适宜模式,并初步提出了提高西安新农村建设规划综合效益的改进策略,以期高效推进西安新农村建设的有序开展。  相似文献   
967.
This paper is concerned with the estimation of a general class of nonlinear panel data models in which the conditional distribution of the dependent variable and the distribution of the heterogeneity factors are arbitrary. In general, exact analytical results for this problem do not exist. Here, Laplace and small-sigma appriximations for the marginal likelihood are presented. The computation of the MLE from both approximations is straightforward. It is shown that the accuracy of the Laplace approximation depends on both the sample size and the variance of the individual effects, whereas the accuracy of the small-sigma approximation is 0(1) with respect to the sample size. The results are applied to count, duration and probit panel data models. The accuracy of the approximations is evaluated through a Monte Carlo simulation experiment. The approximations are also applied in an analysis of youth unemployment in Australia.  相似文献   
968.
We analyze the probability of a random distribution of n balls into m urns of size b resulting in no overflows. This solves the computational problem associated with a classical combinatorial extreme-value distribution. The problem arose during the analysis of a technique, called perfect hashing, for organizing data in computer files. The results and techniques presented can be used to solve several problems in the analysis of hashing techniques  相似文献   
969.
通过抽样考察,可窥见我国理工高校法律人才培养模式总体现状欠佳,其主要存在这样几个问题:一是培养模式未彰显特色,培养目标指向趋于同质,定位模糊;二是培养机制缺乏制度化支撑,长久动力不足,人才培养缺乏竞争优势。理工高校应以应用复合型卓越法律人才培养目标的确立,特定法律人才培养机制的建构,特色法律专业课程的设计和教学方法的创新,以及法律人才培养模式的制度化保障等四个方面为进路,尽快改变理工高校法律人才培养的欠佳状况。  相似文献   
970.
Nonindigenous species have caused significant impacts to North American forests despite past and present international phytosanitary efforts. Though broadly acknowledged, the risks of pest invasions are difficult to quantify as they involve interactions between many factors that operate across a range of spatial and temporal scales: the transmission of invading organisms via various pathways, their spread and establishment in new environments. Our study presents a stochastic simulation approach to quantify these risks and associated uncertainties through time in a unified fashion. We outline this approach with an example of a forest pest recently detected in North America, Sirex noctilio Fabricius. We simulate new potential entries of S. noctilio as a stochastic process, based on recent volumes of marine shipments of commodities from countries where S. noctilio is established, as well as the broad dynamics of foreign marine imports. The results are then linked with a spatial model that simulates the spread of S. noctilio within the geographical distribution of its hosts (pines) while incorporating existing knowledge about its behavior in North American landscapes. Through replications, this approach yields a spatial representation of S. noctilio risks and uncertainties in a single integrated product. The approach should also be appealing to decisionmakers, since it accounts for projected flows of commodities that may serve as conduits for pest entry. Our 30-year forecasts indicate high establishment probability in Ontario, Quebec, and the northeastern United States, but further southward expansion of S. noctilio is uncertain, ultimately depending on the impact of recent international treatment standards for wood packing materials.  相似文献   
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