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271.
Land subsidence risk assessment (LSRA) is a multi‐attribute decision analysis (MADA) problem and is often characterized by both quantitative and qualitative attributes with various types of uncertainty. Therefore, the problem needs to be modeled and analyzed using methods that can handle uncertainty. In this article, we propose an integrated assessment model based on the evidential reasoning (ER) algorithm and fuzzy set theory. The assessment model is structured as a hierarchical framework that regards land subsidence risk as a composite of two key factors: hazard and vulnerability. These factors can be described by a set of basic indicators defined by assessment grades with attributes for transforming both numerical data and subjective judgments into a belief structure. The factor‐level attributes of hazard and vulnerability are combined using the ER algorithm, which is based on the information from a belief structure calculated by the Dempster‐Shafer (D‐S) theory, and a distributed fuzzy belief structure calculated by fuzzy set theory. The results from the combined algorithms yield distributed assessment grade matrices. The application of the model to the Xixi‐Chengnan area, China, illustrates its usefulness and validity for LSRA. The model utilizes a combination of all types of evidence, including all assessment information—quantitative or qualitative, complete or incomplete, and precise or imprecise—to provide assessment grades that define risk assessment on the basis of hazard and vulnerability. The results will enable risk managers to apply different risk prevention measures and mitigation planning based on the calculated risk states.  相似文献   
272.
273.
参照体选择在分配公平、薪酬满意研究中扮演重要角色,而以往研究多是关注焦点对象与参照体在薪酬上的数量差异。本文认为,参照体"数量差异"并不能完整表征参照体的效应,为此提出了"信息知晓度"、"判断关联性"、"比较频率"、"数量差异"等四类表征,在理论基础上构造路径模型与研究假设。实证研究表明,信息知晓度、判断关联性正向影响特定参照体的比较频率;数量差异正向影响分配公平、薪酬水平满意,比较频率负向影响分配公平、薪酬水平满意。通过三种研究路径的比较研究证实,自我生活成本等七类参照体相对重要。未来亟需就参照体选择的相关机制在纵贯上、在不同的组织情境下及考虑个体差异等方面予以深入考察。  相似文献   
274.
A new numerical method to solve the downdating problem (and variants thereof), namely removing the effect of some observations from the generalized least squares (GLS) estimator of the general linear model (GLM) after it has been estimated, is extensively investigated. It is verified that the solution of the downdated least squares problem can be obtained from the estimation of an equivalent GLM, where the original model is updated with the imaginary deleted observations. This updated GLM has a non positive definite dispersion matrix which comprises complex covariance values and it is proved herein to yield the same normal equations as the downdated model. Additionally, the problem of deleting observations from the seemingly unrelated regressions model is addressed, demonstrating the direct applicability of this method to other multivariate linear models. The algorithms which implement the novel downdating method utilize efficiently the previous computations from the estimation of the original model. As a result, the computational cost is significantly reduced. This shows the great usability potential of the downdating method in computationally intensive problems. The downdating algorithms have been applied to real and synthetic data to illustrate their efficiency.  相似文献   
275.
Studies have shown that foster care alumni have disproportionally high rates of poor mental health outcomes compared to the general population. The purpose of this study was to examine differences in mental health service use for Latino, African American, and White youth while in foster care and upon exit from the foster care system. Secondary data were used to identify youth 1 year prior to exiting the foster care system (N?=?934) and 1 year after exit from the foster care system (N?=?433). Racial/ethnic disparities in mental health service use upon exit from the foster care system were found, with Latino youth using the least amount of services after foster care exit. Racial/ethnic service disparities in type of services used were also found. Findings suggest that a lack of support (e.g., mandatory or voluntary) may be significant in overcoming challenges in the continuation or disruption of services.  相似文献   
276.
277.
《鹿特丹规则》的立法宗旨在于实现海上货物运输法律的统一。它对海上货物运输中相关主体的权利义务进行了重新分配,尤其是其中的"门到门"运输,加重了承运人的义务,这种权利义务的再分配,对海上保险法律制度必然会造成一定的影响。文章从《鹿特丹规则》"门到门"运输的基本内涵的研究出发,探讨了"门到门"运输下承运人义务的变化,分析了该规则的主要影响尤其是对海上保险可能造成的影响,以及海上保险法律制度的完善路径。  相似文献   
278.
Taking data from the ‘India Youth Survey: Situation and Needs’ the paper examines intergenerational educational mobility for young females (vis-à-vis their mothers) in India. The paper uses transition/mobility matrices and mobility measures widely used in the literature on intergenerational mobility for the examination. The overall intergenerational educational mobility among the young females in India is about 0.69 (the upper limit being 1). The upwards component of the overall intergenerational educational mobility is 0.55 (that is, nearly four-fifth of the overall). Also, the intergenerational educational mobility is slightly higher in the ‘Scheduled Castes and Tribes (SC/ST)’ compared to the ‘Other Backward Castes (OBC)’ as well as ‘Others’ castes. But the upward mobility is substantially higher in the ‘Others’ caste group compared to SC/STs. The upward mobility among the OBCs is higher than that of SC/STs but lower than that of the ‘Others’ category. Also, the overall mobility as well as upward mobility is higher in urban areas. Moreover, there are large inter-state variations with the economically and demographically poorer states having substantially lower overall as well as upward mobility than the economically and demographically advanced states.  相似文献   
279.
The study analyzed poverty as a function of households’ demographic composition using a longitudinal random sample of 4268 urban and rural households that were followed-up from 2005/6 to 2009/12 in Mexico to estimate short-term changes in living conditions. Well-being was measured as the dwelling unit’s number of rooms, water source, sanitary services, garbage disposal, and fuel. Mobility paths included not poor–not poor, poor–poor, not poor–poor, and poor–not poor. Independent variables included household composition, family characteristics, residential changes, schooling, and occupation. Female headship and older adults negatively impacted poverty, whereas economic dependents may be negatively or positively associated. Fertility incentives for low-income populations are not advisable. Working-age adults contribute only if income-generating opportunities exist locally.  相似文献   
280.
This paper proposes a hierarchical probabilistic model for ordinal matrix factorization. Unlike previous approaches, we model the ordinal nature of the data and take a principled approach to incorporating priors for the hidden variables. Two algorithms are presented for inference, one based on Gibbs sampling and one based on variational Bayes. Importantly, these algorithms may be implemented in the factorization of very large matrices with missing entries.  相似文献   
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