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301.
Urban Ecosystems - Coastal urbanisation, energy extraction, food production, shipping and transportation have led to the global proliferation of artificial structures within the coastal and marine...  相似文献   
302.
We have conducted a longitudinal survey of NIH-funded F32 postdoctoral fellows to determine if mandated instruction in the responsible conduct of research (RCR) has measurable effects on awareness of, attentiveness to, and behavioral judgments about research ethics and authorship and publication. Of 418 F32 fellows participating in the study, 50% were aware of and had referred to guidelines on authorship and publication practices while 50% were either unaware of or had not referred to guidelines. Groups were similar with regard to total number of peer-reviewed publications and total number of first author publications, years of research experience, years since completing their doctoral degree, and receipt of RCR training. The equal distribution of guideline awareness and use, and group similarities with regard to career development and achievement provided us with an opportunity to consider whether awareness of and use of guidelines is associated with broader judgments about author roles and responsibilities. The findings suggest that awareness and utilization of guidelines are, at best, only modestly associated with more ethically appropriate judgments and attitudes about author roles and responsibilities among novice F32's.  相似文献   
303.
This paper describes the GRASP computer aided design system for modelling and evaluating industrial robot workplaces. GRASP satisfies a range of simulation needs within the context of designing, implementing and operating industrial robotic systems. The GRASP software may be used to investigate robots operating by themselves or, more likely, as part of an integrated cell. Facilities within GRASP assist workplace layout, position and velocity evaluations, clash detection and co-ordination between items. A robot library exists and is being extended, and an embryo off-line programming facility has been used under restricted conditions. GRASP has been used to help solve a wide range of practical industrial robot problems and has proved itself technically, and also as an educational tool, by showing how a proposed system would operate. The paper describes the facilities within GRASP.  相似文献   
304.
This paper provides some simple methods of interpreting the coefficients in multinomial logit and ordered logit models. These methods are summarized in Propositions concerning the magnitudes, signs, and patterns of partial derivatives of the outcome probabilities with respect to the exogenousvariables. The paper also provides an empirical example illustrating the use of these Propositions.  相似文献   
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306.
The article reports on the results of an evaluation of a school drug and alcohol prevention curriculum marketed under the title, "Here's Looking at You, Two." Previous evaluations, unreported in the literature and having unresolved methodological problems, have found that while the program appears effective at transmitting information regarding drug and alcohol abuse, it has not been effective at changing the underlying attitudes and behaviors that, in part, explain substance abuse. Employing a more rigorous methodology, our examination of a relatively large sample across five school districts provides support for previous findings. Over the short-term of one year, the program was particularly effective at transmitting substance information to primary and middle school students. The program, however, produced very little of the expected effect on the underlying attitudes that are critical to changing substance abuse behaviors.  相似文献   
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308.
Environmental and public health organizations, including the World Health Organization (WHO) and the U.S. Environmental Protection Agency (USEPA), develop human health reference values (HHRV) that set “safe” levels of exposure to noncarcinogens. Here, we systematically analyze chronic HHRVs from four organizations: USEPA, Health Canada, RIVM (the Netherlands), and the U.S. Agency for Toxic Substances and Disease Registry. This study is an extension of our earlier work and both closely examines the choices made in setting HHRVs and presents a quantitative method for identifying the primary factors influencing HHRV agreement or disagreement.(1) We evaluated 171 organizational comparisons, developing a quantitative method for identifying the factors to which HHRV agreement (that is, when both organizations considering the same data set the identical HHRV values) is most sensitive. To conduct this analysis, a Bayesian belief network was built using expert judgment, including the specific science policy choices analysis made in the context of setting an HHRV. Based on a sensitivity of findings analysis, HHRV agreement is most sensitive to the point of departure value, followed by the total uncertainty factor (UF), critical study, critical effect, animal model, and point of departure approach. This analysis also considered the specific impacts of individual UFs, with the database UF and the subchronic‐to‐chronic UF being identified as primary factors impacting the total UF differences observed across organizations. The sensitivity of findings analysis results were strengthened and confirmed by frequency analyses evaluating which choices most often disagreed when the HHRV and the total UF disagreed.  相似文献   
309.
The goal of this study was to systematically evaluate the choices made in deriving a chronic oral noncancer human health reference value (HHRV) for a given chemical by different organizations, specifically those from the U.S. Environmental Protection Agency, Health Canada, RIVM (the Netherlands), and the U.S. Agency for Toxic Substances and Disease Registry. This analysis presents a methodological approach for comparing both the HHRVs and the specific choices made in the process of deriving an HHRV across these organizations. Overall, across the 96 unique chemicals and 171 two‐way organizational comparisons, the HHRV agreed approximately 26% of the time. A qualitative method for identifying the primary factors influencing these HHRV differences was also developed, using arrays of HHRVs across organizations for the same chemical. The primary factors identified were disagreement on the critical or principal study and differential application of the total uncertainty factor across organizations. Of the cases where the total UF was the primary factor influencing HHRV disagreement, the database UF had the greatest influence.  相似文献   
310.
Drawing on social exchange processes in leader-member exchange (LMX), we posit that expressive relational schema (ERS) and instrumental relational schema (IRS), which refer to knowledge structures in social exchange processes, act as antecedents of follower-rated LMX. Specifically, we discuss how leader-follower relational schema congruence/incongruence informs follower-rated LMX. Using polynomial regression models, we analyze 205 leader-follower dyads and test the congruent/incongruent effects on follower-rated LMX. The findings show that ERS congruence has a positive effect on follower-rated LMX, while IRS congruence has a negative effect on follower-rated LMX. Results also demonstrate that ERS incongruence impairs more follower-rated LMX than does ERS congruence, and IRS incongruence and IRS congruence have the same follower-rated LMX. Implications for LMX theory and research are discussed.  相似文献   
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