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   8279篇
  免费   218篇
  国内免费   1篇
管理学   1132篇
民族学   30篇
人口学   717篇
丛书文集   31篇
理论方法论   720篇
综合类   140篇
社会学   3762篇
统计学   1966篇
  2023年   53篇
  2020年   126篇
  2019年   183篇
  2018年   176篇
  2017年   272篇
  2016年   185篇
  2015年   163篇
  2014年   191篇
  2013年   1542篇
  2012年   263篇
  2011年   209篇
  2010年   192篇
  2009年   169篇
  2008年   231篇
  2007年   229篇
  2006年   192篇
  2005年   162篇
  2004年   142篇
  2003年   130篇
  2002年   145篇
  2001年   185篇
  2000年   164篇
  1999年   150篇
  1998年   129篇
  1997年   128篇
  1996年   126篇
  1995年   112篇
  1994年   85篇
  1993年   126篇
  1992年   138篇
  1991年   119篇
  1990年   130篇
  1989年   108篇
  1988年   107篇
  1987年   111篇
  1986年   99篇
  1985年   84篇
  1984年   116篇
  1983年   99篇
  1982年   94篇
  1981年   65篇
  1980年   93篇
  1979年   105篇
  1978年   72篇
  1977年   82篇
  1976年   71篇
  1975年   85篇
  1974年   68篇
  1973年   54篇
  1972年   61篇
排序方式: 共有8498条查询结果,搜索用时 171 毫秒
151.
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   
152.
153.
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   
154.
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   
155.
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   
156.
157.
For over 20 years, family therapist Karl Tomm has been engaging families and couples with a therapeutic intervention he calls Internalized Other Interviewing (IOI). The IOI (cf. Emmerson‐Whyte, 2010; Hurley, 2006) entails interviewing clients, from the personal experiences of partners and family members as an internalized other. The IOI is based on the idea that through dialogues over time, one can internalize a sense of one's conversational partner responsiveness in reliably anticipated ways. Anyone who has thought in a conversation with a family member or partner, “Oh there s/he goes again,” or anticipates next words before they leave the other's mouth, has a sense of what we are calling an internalized other. For Tomm, the internalized anticipations partners and family members may have offers entry points into new dialogues with therapeutic potential—particularly, when their actual dialogues get stuck in dispreferred patterns.  相似文献   
158.
159.
Melamine contamination of food has become a major food safety issue because of incidents of infant disease caused by exposure to this chemical. This study was aimed at establishing a safety limit in Taiwan for the degree of melamine migration from food containers. Health risk assessment was performed for three exposure groups (preschool children, individuals who dine out, and elderly residents of nursing homes). Selected values of tolerable daily intake (TDI) for melamine were used to calculate the reference migration concentration limit (RMCL) or reference specific migration limit (RSML) for melamine food containers. The only existing values of these limits for international standards today are 1.2 mg/L (0.2 mg/dm2) in China and 30 mg/L (5 mg/dm2) in the European Union. The factors used in the calculations included the specific surface area of food containers, daily food consumption rate, body weight, TDI, and the percentile of the population protected at a given migration concentration limit (MCL). The results indicate that children are indeed at higher risk of melamine exposure at toxic levels than are other groups and that the 95th percentile of MCL (specific surface area = 5) for children aged 1–6 years should be the RMCL (0.07 mg/dm2) for protecting the sensitive and general population.  相似文献   
160.
Preferential trade agreements (PTAs) have proliferated over the past 60 years. While a small number of recent studies have examined empirically the economic determinants of the likelihood of a pair of countries having a PTA, this study explains empirically the timing of all PTA formations and enlargements from 1950 through 2006 using duration analysis. Our main and novel goal is to predict (in‐ and out‐of‐sample) a substantive share of these 1,560 PTA events using a parsimonious model with mainly economic variables, taking selection dynamics into account. Our analysis reveals that we can predict correctly in‐sample the actual year of entry into force for 26% of the 1,560 bilateral PTA formations/enlargements in the period 1950–2006 among 10,518 pairings of 146 countries using only a few economic and political variables. Moreover, we can predict correctly in‐sample 57% of these PTA events within a 10‐year window leading up to the event using this model. The model also performs well out‐of‐sample for the near term (82%), but not if the out‐of‐sample period is very long. We conclude with an evaluation of the model's ability to predict the timing of the North American Free Trade Agreement, the European Union's formation and enlargements, and the model's ten most likely post‐2006 PTA events. (JEL F14, F15)  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