首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   17398篇
  免费   777篇
  国内免费   225篇
管理学   1947篇
劳动科学   2篇
民族学   98篇
人才学   3篇
人口学   340篇
丛书文集   940篇
理论方法论   491篇
综合类   8386篇
社会学   796篇
统计学   5397篇
  2024年   26篇
  2023年   154篇
  2022年   245篇
  2021年   270篇
  2020年   400篇
  2019年   521篇
  2018年   563篇
  2017年   689篇
  2016年   590篇
  2015年   622篇
  2014年   978篇
  2013年   2249篇
  2012年   1291篇
  2011年   1142篇
  2010年   933篇
  2009年   918篇
  2008年   1008篇
  2007年   997篇
  2006年   895篇
  2005年   755篇
  2004年   641篇
  2003年   522篇
  2002年   477篇
  2001年   408篇
  2000年   248篇
  1999年   186篇
  1998年   104篇
  1997年   113篇
  1996年   82篇
  1995年   67篇
  1994年   53篇
  1993年   45篇
  1992年   41篇
  1991年   42篇
  1990年   25篇
  1989年   20篇
  1988年   16篇
  1987年   9篇
  1986年   8篇
  1985年   13篇
  1984年   8篇
  1983年   9篇
  1982年   5篇
  1981年   2篇
  1980年   1篇
  1979年   4篇
  1978年   3篇
  1977年   1篇
  1975年   1篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
In this note, it is shown that the finite-sample distributions of the Wald, likelihood ratio, and Lagrange multiplier statistics in the classical linear regression model are members of the generalized beta model introduced by McDonald and Xu (1995a McDonald, J.B., Xu, Y.J. (1995a). A generalization of the beta distribution with applications. J. Econom. 66:133152.[Crossref], [Web of Science ®] [Google Scholar]). This is useful for examining the properties of these test statistics. For example, this characterization makes it easy to find distribution, quantile, and density functions for each test statistic, makes it clear why Wald tests may overreject the null hypothesis using asymptotic critical values, and formalizes the fact that the Lagrange multiplier statistic follows a distribution with bounded support.  相似文献   
993.
Here we consider a multinomial probit regression model where the number of variables substantially exceeds the sample size and only a subset of the available variables is associated with the response. Thus selecting a small number of relevant variables for classification has received a great deal of attention. Generally when the number of variables is substantial, sparsity-enforcing priors for the regression coefficients are called for on grounds of predictive generalization and computational ease. In this paper, we propose a sparse Bayesian variable selection method in multinomial probit regression model for multi-class classification. The performance of our proposed method is demonstrated with one simulated data and three well-known gene expression profiling data: breast cancer data, leukemia data, and small round blue-cell tumors. The results show that compared with other methods, our method is able to select the relevant variables and can obtain competitive classification accuracy with a small subset of relevant genes.  相似文献   
994.
This qualitative study focuses on the different ways time is experienced by children in families who face time challenges because of a family member's job that required work travel. Data are from a family‐level study that includes interviews of all family members older than age 7. Using grounded theory methodology, this study illustrates the ways in which job demands and family processes interact. The analysis centers on 75 children's perspectives from 43 families. Holding together assessments of having enough time while wanting more time with their parents, children express emotion, generally unrecognized by parents, around the topic of family time. Children's experience of time with parents is rushed or calm, depending on the activities done in time and the gender of the parent with whom they spend time. Findings are interpreted through a feminist social constructionist lens.  相似文献   
995.
This paper analyses the importance of evaluating the various components of the programmes or actions carried out by education organisations. It highlights the need to assess the impact of the intervention on the organisation and consider how changes are consolidated over time in interaction with the context. We propose an impact evaluation model and as an example have chosen the implementation of Quality Management Systems in schools. The paper analyses the results obtained in 40 schools in three regions (Spanish Autonomous Communities) with varying levels of implementation. The results show overall impact on these education centres as the teachers and management teams of the centres perceive it. This impact is more evident in some of the dimensions considered in the study than in others. The results also confirm the differences between regional contexts.  相似文献   
996.
What do clients/patients want or value from their encounters with healthcare providers? Based on ethnographic research conducted with individuals suffering from drug addiction and mental health issues, this article argues that clients/patients treasure “everyday” or “human” interaction with medical staff. Everydayness is accomplished through three generic social processes: **co‐silence, inclusion in back‐stage activity, and physical dramatizations of authenticity. These processes and other ordinary interactional strategies for “being human together” should be seen as vital tools for recovery.  相似文献   
997.
998.

Background

Following childbirth, a vast number of women experience some degree of mood swings, while some experience symptoms of postpartum posttraumatic stress disorder.

Aim

Using a biopsychosocial model, the primary aim of this study was to identify predictors of posttraumatic stress disorder and its symptomatology following childbirth.

Methods

This observational, longitudinal study included 372 postpartum women. In order to explore biopsychosocial predictors, participants completed several questionnaires 3–5 days after childbirth: the Impact of Events Scale Revised, the Big Five Inventory, The Edinburgh Postnatal Depression Scale, breastfeeding practice and social and demographic factors. Six to nine weeks after childbirth, participants re-completed the questionnaires regarding psychiatric symptomatology and breastfeeding practice.

Findings

Using a multivariate level of analysis, the predictors that increased the likelihood of postpartum posttraumatic stress disorder symptomatology at the first study phase were: emergency caesarean section (odds ratio 2.48; confidence interval 1.13–5.43) and neuroticism personality trait (odds ratio 1.12; confidence interval 1.05–1.20). The predictor that increased the likelihood of posttraumatic stress disorder symptomatology at the second study phase was the baseline Impact of Events Scale Revised score (odds ratio 12.55; confidence interval 4.06–38.81). Predictors that decreased the likelihood of symptomatology at the second study phase were life in a nuclear family (odds ratio 0.27; confidence interval 0.09–0.77) and life in a city (odds ratio 0.29; confidence interval 0.09–0.94).

Conclusion

Biopsychosocial theory is applicable to postpartum psychiatric disorders. In addition to screening for depression amongst postpartum women, there is a need to include other postpartum psychiatric symptomatology screenings in routine practice.  相似文献   
999.
Abstract

Manufacturing applications address business to business (B2B) with highly customised applications developed for specific requirements, offering highly specialised solution-oriented and service-based software components, systems, and digital tools that aim at a fast and accurate decision-making support system. The purpose of this paper is to describe the implementation of digital technologies for operations management using manufacturing or engineering apps (eApps), for product design and manufacturing processes. In particular, starting from the specific needs of two companies from mature European industries as automotive and food, this work depicts how this kind of solutions can support companies and improve their operations. In particular, related benefits and challenges faced for the full implementation of the developed tools are highlighted. Moreover a business model to exploit the manufacturing apps is also proposed. The business model proposed for the exploitation of the eApps supports the commercialisation of all the revenue streams offered by this rapidly growing sector taking into account the specific needs of the concerned stakeholders through a diversified value proposition.  相似文献   
1000.
What motivates the geographic footprint of the supply chains that multinational firms (MNFs) deploy? Traditional research in the operations and supply chain management literature tends to recommend locations primarily based on differentials in production costs and the ramifications of physical distance ignoring the role of taxation. MNFs that strategically position parts of their supply chains in low‐tax locations can allocate the profits across the divisions to improve post‐tax profits. For the profit allocation to be defensible to tax authorities, the divisional operations must possess real decision authority and bear meaningful risks. Generally speaking, the greater the transfer of risk and control, the larger the allowable allocation of profit. These transfers may also create inefficiencies due to misalignment of business goals and attitudes toward risk. We model these trade‐offs in the context of placing in a low‐tax region a subsidiary that oversees product distribution (as a limited risk distributor commissionnaire, limited risk distributor, or fully fledged distributor). Our analysis demonstrates that the MNF's preferences regarding the operating structures are not necessarily an obvious ordering based on the amount of risk and decision authority transferred to the division in the low‐tax jurisdiction. We derive and analyze threshold values of the performance parameters that describe the main trade‐offs involved in selecting an operating structure. We find some of the optimal decisions to exhibit interesting non‐monotone behavior. For instance, profits can increase when the tax rate in the low‐tax jurisdiction increases. Numerical analysis shows that the Limited‐Risk Distributor structure is rarely optimal and quantifies when each alternative dominates it.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号