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281.
Local influence on the eigenvalues of sample covariance matrices in principal components analysis is examined for a reasonable modification of Shi's (1997) perturbation scheme, The modification is suggested for samples from populations with both unknown mean vector and covariance matrix. While Shi's detection indexes (1997) consist of only quadratic terms, the modified perturbation scheme leads to detection indexes constituted by both linear and quadratic terms associated with centralized observations. These linear and quadratic terms reflect local influences on the first two sample moments. Examples are investigated based on the two detection indexes. 相似文献
282.
Jan Serroyen Marc Aerts Ellen Vloeberghs Peter Paul De Deyn Geert Verbeke 《Journal of applied statistics》2010,37(5):833-846
In the conventional linear mixed-effects model, four structures can be distinguished: fixed effects, random effects, measurement error and serial correlation. The latter captures the phenomenon that the correlation structure within a subject depends on the time lag between two measurements. While the general linear mixed model is rather flexible, the need has arisen to further increase flexibility. In addition to work done in the area, we propose the use of spline-based modeling of the serial correlation function, so as to allow for additional flexibility. This approach is applied to data from a pre-clinical experiment in dementia which studied the eating and drinking behavior in mice. 相似文献
283.
Adinda Dujardin Rudi De Raedt Jessica L. Borelli Caroline Braet Pieter Vos Mike Rinck Guy Bosmans 《Social Development》2019,28(2):364-382
In this study we investigated the effects of seeking versus avoiding proximity to mother on children’s emotional recovery from a stressor. Sixty children 9–12 years underwent a moodinduction procedure and were randomly assigned to seek proximity from or avoid an image of their mothers. The effect of this manipulation on children’s self‐reported negative emotions, skin conductance and heart rate variability (respiratory sinus arhythmia) was assessed. Higher levels of attachment anxiety were linked to more self‐reported sadness when children had to avoid mother, but no evidence for such an effect was found on a physiological level. For avoidant attachment, a similar pattern of results emerged, but both for self‐reported sadness and skin conductance. 相似文献
284.
Microbiological and Modeling Approach to Derive Performance Objectives for Bacillus cereus Group in Ready‐to‐Eat Salads 下载免费PDF全文
Alessandra De Cesare Silvia Vitali Marcello Trevisani Federica Bovo Gerardo Manfreda 《Risk analysis》2017,37(3):408-420
In this article, the performance objectives (POs) for Bacillus cereus group (BC) in celery, cheese, and spelt added as ingredients in a ready‐to‐eat mixed spelt salad, packaged under modified atmosphere, were calculated using a Bayesian approach. In order to derive the POs, BC detection and enumeration were performed in nine lots of naturally contaminated ingredients and final product. Moreover, the impact of specific production steps on the BC contamination was quantified. Finally, a sampling plan to verify the ingredient lots' compliance with each PO value at a 95% confidence level (CL) was defined. To calculate the POs, detection results as well as results above the limit of detection but below the limit of quantification (i.e., censored data) were analyzed. The most probable distribution of the censored data was determined and two‐dimensional (2D) Monte Carlo simulations were performed. The PO values were calculated to meet a food safety objective of 4 log10 cfu of BC for g of spelt salad at the time of consumption. When BC grows during storage between 0.90 and 1.90 log10 cfu/g, the POs for BC in celery, cheese, and spelt ranged between 1.21 log10 cfu/g for celery and 2.45 log10 cfu/g for spelt. This article represents the first attempt to manage the concept of PO and 2D Monte Carlo simulation in the flow chart of a complex food matrix, including raw and cooked ingredients. 相似文献
285.
关于反腐倡廉对策的思考 总被引:1,自引:0,他引:1
理想教育、宗旨教育、传统教育、法制教育是反腐倡廉的基础。完善制度、健全法律 ,严格依法办事是反腐倡廉的保证。普及权力监督意识、强化监督功能 ,健全监督机制、增强监督力度 ,狠抓落实问题 ,使监督落到实处 ,是反腐倡廉的关键。只有三管齐下 ,反腐倡廉才能真正取得实效 相似文献
286.
Santa Parrello Ilaria Iorio Barbara De Rosa Massimiliano Sommantico 《Social Work Education》2020,39(5):584-598
ABSTRACT The Association ‘Maestri di Strada’ (MdS) undertakes socio-educational interventions to promote the well-being of young people in the ‘high-risk’ suburbs of Naples. The socio-educational work is not a mere ‘technical-rational’ activity and it relies on the use of ‘self’, which is not an unlimited resource. MdS places great emphasis upon reflexivity after the action and adopts the ‘Multi-Vision Group’ (MVG), which is a modified Balint group, as a support mechanism for its staff. Before trainees begin working, they attend the MVGs, observe them, and provide narrative accounts of the process. In this study, 61 reports prepared by the trainees during an academic year underwent a textual analysis. The aim was to evaluate the reflexive function of the group and the results indicate that, within the MVG, the practitioners express emotions, doubts, and difficulties linked to the job and its high-risk contexts. They show both self-awareness and awareness of the importance of the team, thinking as a community in a cooperative way. These are features related to reflexivity, which is recognised as being crucial for practice; the process of observation and recording also has a high educational importance for the trainees and social work students. 相似文献
287.
The total ban on use of meat and bone meal (MBM) in livestock feed has been very successful in reducing bovine spongiform encephalopathy (BSE) spread, but also implies a waste of high-quality proteins resulting in economic and ecological loss. Now that the BSE epidemic is fading out, a partial lifting of the MBM ban might be considered. The objective of this study was to assess the BSE risk for the Netherlands if MBM derived from animals fit for human consumption, i.e., category 3 MBM, would be used in nonruminant feed. A stochastic simulation model was constructed that calculates (1) the probability that infectivity of undetected BSE-infected cows ends up with calves and (2) the quantity of infectivity ( Qinf ) consumed by calves in case of such an incident. Three pathways were considered via which infectivity can reach cattle: (1) cross-contamination in the feed mill, (2) cross-contamination on the primary farm, and (3) pasture contamination. Model calculations indicate that the overall probability that infectivity ends up with calves is 3.2%. In most such incidents the Qinf is extremely small (median = 6.5 × 10−12 ID50 ; mean = 1.8 × 10−4 ID50 ), corresponding to an average probability of 1.3 × 10−4 that an incident results in ≥1 new BSE infections. Cross-contamination in the feed mill is the most risky pathway. Combining model results with Dutch BSE prevalence estimates for the coming years, it can be concluded that the BSE risk of using category 3 MBM derived from Dutch cattle in nonruminant feed is very low. 相似文献
288.
We consider a situation where an individual is facing an uncertain situation, but may costly alter his knowledge of the uncertainties. We study in this context how risk aversion may modify the individual search behavior. We consider a one-armed bandit problem (where one arm is safe and the other is risky) and study how the agent risk aversion can change the sequence of arms selected. The main result is that when the utility function is more concave, the agent has more chances to select the safe arm. We also discuss how search is affected by risk aversion. 相似文献
289.
Due to the significant role of non‐profit organizations in the development of modern societies, these organizations must adjust their boardrooms. Since traditional theories of corporate governance appear to be limited in explaining the changing non‐profit world, we propose an extended model of governance that integrates the traditional arguments of agency theory with a cognitive dimension. Based on a sample of Spanish foundations, we present evidence on the effect of the board composition on foundations' organizational efficiency. We show that board size and independence do not have a definitive effect on the entity's efficiency. Instead, the knowledge diversity inside the boardroom and the active character of trustees have a positive influence on resource allocation. The cognitive dimension of the extended model of governance is critical to explaining how boards impact on organizational performance. 相似文献
290.
The paper presents a hierarchical framework for production control of hospitals which deals with the balance between service and efficiency, at all levels of planning and control. The framework is based on an analysis of the design requirements for hospital production control systems. These design requirements are translated into the control functions at different levels of planning required for hospital production control. The framework consists of five levels of planning and control: patient planning and control, patient group planning and control, resources planning and control, patient volumes planning and control and strategic planning, though this last level does not make part of production control as such. Each of the levels of the framework is further elaborated in terms of the decisions made regarding patient flows and resources, and the co-ordination of the different planning levels. Implications of the framework are discussed by describing some points where current practice deviates from assumptions made in our approach. Recommendations for future research and development of the planning framework are formulated. 相似文献