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   8736篇
  免费   138篇
  国内免费   1篇
管理学   1179篇
民族学   30篇
人口学   752篇
丛书文集   34篇
理论方法论   773篇
综合类   137篇
社会学   4013篇
统计学   1957篇
  2023年   54篇
  2020年   122篇
  2019年   186篇
  2018年   182篇
  2017年   277篇
  2016年   194篇
  2015年   168篇
  2014年   205篇
  2013年   1606篇
  2012年   264篇
  2011年   230篇
  2010年   206篇
  2009年   174篇
  2008年   239篇
  2007年   244篇
  2006年   203篇
  2005年   176篇
  2004年   161篇
  2003年   145篇
  2002年   164篇
  2001年   195篇
  2000年   173篇
  1999年   157篇
  1998年   140篇
  1997年   136篇
  1996年   131篇
  1995年   119篇
  1994年   90篇
  1993年   132篇
  1992年   145篇
  1991年   119篇
  1990年   135篇
  1989年   113篇
  1988年   112篇
  1987年   112篇
  1986年   104篇
  1985年   86篇
  1984年   119篇
  1983年   104篇
  1982年   97篇
  1981年   64篇
  1980年   97篇
  1979年   105篇
  1978年   73篇
  1977年   83篇
  1976年   75篇
  1975年   86篇
  1974年   68篇
  1973年   54篇
  1972年   61篇
排序方式: 共有8875条查询结果,搜索用时 0 毫秒
141.
Summary It is generally conceded that our allied mental health professions have fallen short in our attempts to provide adequate services to those people whose need is most desperate, those individuals and families ambiguously and condescendingly designated multiproblem. It could be said that we, the caregivers, have been unwilling or unable to be good enough mothers to these, our motherless children. In fact, the early, formative experience of the people with whom we are concerned has invariably been marked by gross discontinuities in mothering; the consequent defects in controlling, regulatory psychic structure (ego defects) are most prominently manifested in the chaotic life-style which characterizes these individuals and families. Our task as caregivers, when viewed from this perspective, is clear: we must somehow bring order out of disorder. But, with tragic regularity, disorder prevails; the provider of service succumbs to the same painful feelings of disorganization, bewilderment, frustration, and helplessness with which his client struggles, and, eventually, both give up in despair. What is more, this sense of fragmentation and futility pervades the institutions responsible for provision of services. Client, caregiver, and institution, all are trapped in the same tortuous maze. How, then, are we to extricate ourselves? Certainly not by drafting yet another master plan which promises everything and delivers nothing. Both realistic and humanistic considerations dictate more modest goals: We might not be able to rescue everyone who needs assistance, but we can help a few. And, whatever approach we may adopt, the service we offer can only be effective if it is based upon a sustained and sustaining (in essence, maternal) relationship.Sometimes I Feel Like a Motherless Child  相似文献   
142.
143.
Priority Setting for the Distribution of Localized Hazard Protection   总被引:1,自引:0,他引:1  
We address the problem of distributing safety-enhancing devices across a region, where each identical device provides for only local protection of the population. The devices protect nonidentical sectors of the population. The sectors of population are exposed to nonidentical intensities of hazard. A method for the screening and prioritizing of needs for the protective devices is described. An approach of risk-benefit-cost analysis under uncertainty is recommended as follows. Measures of hazard intensity and population exposure are identified. Exogenous parameters that influence assessments of risks, benefits, and costs are identified. Uncertainties of the exogenous parameters are propagated by interval analysis. Several tiers of the plausibility of need for protection are identified. The tiers are useful in setting priorities for the distribution of the safety devices. The method is demonstrated in an engineering application to roadway lighting, but has implications for disaster preparedness, anti-terrorism, transportation safety, and other arenas of public safety.  相似文献   
144.
In the pursuit of faster product development, product design teams are a growing phenomenon in many organizations. In order to be successful, these teams must be composed of people who work well together. However, despite the benefit of selecting the optimal combination of team members, this topic has received little attention. Personality has been identified as a potentially helpful selection variable in the determination of optimal team composition. This study examines the relationships between the ‘Big Five’ personality factors (Conscientiousness, Extraversion, Neuroticism, Agreeableness, and Openness to Experience) and objective team performance for three-member product design teams. In addition to this, the potential incremental contribution of personality to the variance in team performance over that accounted for by established selection measures such as general cognitive ability was investigated. In the short duration of the study, it became apparent that some teams were capable of success, and some were not. Successful teams were characterized by higher levels of general cognitive ability, higher extraversion, higher agreeableness, and lower neuroticism than their unsuccessful counterparts. In successful teams, the heterogeneity of conscientiousness was negatively related to increments in product performance. Implications for the selection of product design teams and future directions for research are discussed.  相似文献   
145.
Consider the problem of partitioning n nonnegative numbers into p parts, where part i can be assigned ni numbers with ni lying in a given range. The goal is to maximize a Schur convex function F whose ith argument is the sum of numbers assigned to part i. The shape of a partition is the vector consisting of the sizes of its parts, further, a shape (without referring to a particular partition) is a vector of nonnegative integers (n1,..., np) which sum to n. A partition is called size-consecutive if there is a ranking of the parts which is consistent with their sizes, and all elements in a higher-ranked part exceed all elements in the lower-ranked part. We demonstrate that one can restrict attention to size-consecutive partitions with shapes that are nonmajorized, we study these shapes, bound their numbers and develop algorithms to enumerate them. Our study extends the analysis of a previous paper by Hwang and Rothblum which discussed the above problem assuming the existence of a majorizing shape. This research is partially supported by ROC National Science grant NSC 92-2115-M-009-014.  相似文献   
146.
147.
148.
149.
Research suggests that victims of bullying may lack skills in emotional regulation, a process which facilitates coping with provocative situations to lessen the stress of negative emotions (Cicchetti, Ackerman, & Izard, 1995). The present study examined the emotional regulation and display patterns of victims during classroom bullying episodes. Children in grades one through six were observed during free play in the winter and spring of three consecutive school years. Results of the study indicated that the coping styles observed in victims of bullying can be grouped into two distinct clusters: 1) problem-solving strategies that are associated with the de-escalation and resolution of bullying episodes; and 2) aggressive strategies that tend to perpetuate and escalate the bullying interaction. Parallels were found between victims' and bullies' emotional displays. Results are discussed in the context of how maladaptive emotional regulation processes may act as risk factors for chronic victimization.  相似文献   
150.
Kontkanen  P.  Myllymäki  P.  Silander  T.  Tirri  H.  Grünwald  P. 《Statistics and Computing》2000,10(1):39-54
In this paper we are interested in discrete prediction problems for a decision-theoretic setting, where the task is to compute the predictive distribution for a finite set of possible alternatives. This question is first addressed in a general Bayesian framework, where we consider a set of probability distributions defined by some parametric model class. Given a prior distribution on the model parameters and a set of sample data, one possible approach for determining a predictive distribution is to fix the parameters to the instantiation with the maximum a posteriori probability. A more accurate predictive distribution can be obtained by computing the evidence (marginal likelihood), i.e., the integral over all the individual parameter instantiations. As an alternative to these two approaches, we demonstrate how to use Rissanen's new definition of stochastic complexity for determining predictive distributions, and show how the evidence predictive distribution with Jeffrey's prior approaches the new stochastic complexity predictive distribution in the limit with increasing amount of sample data. To compare the alternative approaches in practice, each of the predictive distributions discussed is instantiated in the Bayesian network model family case. In particular, to determine Jeffrey's prior for this model family, we show how to compute the (expected) Fisher information matrix for a fixed but arbitrary Bayesian network structure. In the empirical part of the paper the predictive distributions are compared by using the simple tree-structured Naive Bayes model, which is used in the experiments for computational reasons. The experimentation with several public domain classification datasets suggest that the evidence approach produces the most accurate predictions in the log-score sense. The evidence-based methods are also quite robust in the sense that they predict surprisingly well even when only a small fraction of the full training set is used.  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