全文获取类型
收费全文 | 24302篇 |
免费 | 394篇 |
国内免费 | 3篇 |
专业分类
管理学 | 3623篇 |
民族学 | 183篇 |
人才学 | 9篇 |
人口学 | 3584篇 |
丛书文集 | 74篇 |
理论方法论 | 1873篇 |
综合类 | 435篇 |
社会学 | 10946篇 |
统计学 | 3972篇 |
出版年
2023年 | 79篇 |
2021年 | 86篇 |
2020年 | 226篇 |
2019年 | 321篇 |
2018年 | 2006篇 |
2017年 | 2076篇 |
2016年 | 1424篇 |
2015年 | 317篇 |
2014年 | 390篇 |
2013年 | 2355篇 |
2012年 | 783篇 |
2011年 | 1571篇 |
2010年 | 1370篇 |
2009年 | 1074篇 |
2008年 | 1131篇 |
2007年 | 1350篇 |
2006年 | 367篇 |
2005年 | 609篇 |
2004年 | 583篇 |
2003年 | 533篇 |
2002年 | 398篇 |
2001年 | 321篇 |
2000年 | 353篇 |
1999年 | 302篇 |
1998年 | 239篇 |
1997年 | 232篇 |
1996年 | 246篇 |
1995年 | 191篇 |
1994年 | 214篇 |
1993年 | 186篇 |
1992年 | 234篇 |
1991年 | 187篇 |
1990年 | 175篇 |
1989年 | 172篇 |
1988年 | 178篇 |
1987年 | 143篇 |
1986年 | 145篇 |
1985年 | 166篇 |
1984年 | 180篇 |
1983年 | 182篇 |
1982年 | 156篇 |
1981年 | 140篇 |
1980年 | 137篇 |
1979年 | 139篇 |
1978年 | 124篇 |
1977年 | 111篇 |
1976年 | 110篇 |
1975年 | 95篇 |
1974年 | 93篇 |
1973年 | 78篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
331.
Summary Ledermann's one- and two-parameter model life tables are used in order to summarize and compare adult mortality estimates derived from parental survival data, and also to link parental survival with child survival data. The Ledermann models provide an alternative to the logit model used by Brass and Hill. Examination of life tables derived from actual child and adult mortality estimates reveals that although the two types of models yield similar overall levels of mortality, they show marked differences in the estimated patterns by sex and age. It has not been possible to disentangle completely how much of this divergence is due to the models themselves and how much to inadequacies in the data available. Finally, we question whether it is always wise to establish a full life table from child and adult mortality estimates when these are based on data which refer to different periods of exposure to the risk of dying, without allowance for possible distortions resulting from mortality change. 相似文献
332.
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
333.
George PM Ebanks GE Nobbe CE Anwar M 《International journal of sociology of the family》1976,6(1):57-69
Data from an island-wide probability sample of 4119 Barbadian females aged 16-50 were used to study whether there has been an intergenerational fertility decline between the respondents and their mothers. The fertility of the respondents, all from the low or lower middle class, was significantly lower than that of their mothers. However, the size of the family of procreation was seen to be positively related to the size of the family of orientation; i.e., those from large families tended to have large families and vice versa. There was, however, a regression to the mean. There were no differences between women from small and large families as to fertility norms, age at 1st use of contraceptives, or actual practice of contraception. Women from small families did tend to enter sexual relationships and get pregnant at a later age. The women from small families were better educated, earned higher incomes, and had higher status occupations, all factors which might have influenced their fertility. Women from larger families cited higher numbers for both small and large families than did the women from small families. This indicates a perceptual difference which was, in turn, related to fertility differences. 相似文献
334.
In the binary single constraint Knapsack Problem, denoted KP, we are given a knapsack of fixed capacity c and a set of n items. Each item j, j = 1,...,n, has an associated size or weight wj and a profit pj. The goal is to determine whether or not item j, j = 1,...,n, should be included in the knapsack. The objective is to maximize the total profit without exceeding the capacity c of the knapsack. In this paper, we study the sensitivity of the optimum of the KP to perturbations of either the profit or the weight of an item. We give approximate and exact interval limits for both cases
(profit and weight) and propose several polynomial time algorithms able to reach these interval limits. The performance of
the proposed algorithms are evaluated on a large number of problem instances. 相似文献
335.
336.
The matching identification problem (MIP) is a combinatoric search problem related to the fields of learning from examples, boolean functions, and knowledge acquisition. The MIP involves identifying a single “goal” item from a large set of items. Because there is commonly a cost associated with evaluating each guess, the goal item should be identified in as few guesses as possible. As in most search problems, the items have a similar structure, which allows an evaluation of each guessed item. In other words, each guessed item elicits partial information about the goal item, i.e. how similar the guess is to the goal. With this information the goal is more quickly identified.The unordered MIP has been studied by Mehrez and Steinberg (ORSA J. Comput. 7 (1995) 211) in which they proposed two different types of algorithms. The purpose of the present paper is to suggest an improved Spanning Heuristic algorithm. Its improvement increases as the problem size increases. Further results and comparisons are derived for the unordered and ordered cases.This research shows that when the search space is very large, it is better to inquire from items that are known not to be the goal (they have been ruled out by previous guesses), for the purpose of acquiring more information about the goal. As the search space is narrowed, it is better to guess items that have not been ruled out. 相似文献
337.
338.
Ohne Zusammenfassung 相似文献
339.
Astrid Schreyögg 《Organisationsberatung, Supervision, Coaching》2005,12(4):397-402
Dual Career Couples as a form of work-life-integrationThe author discusses the situation of dual career couples, when both are university graduates following an own career. Basing on a respective publication she delineates the current, mostly American research and reports on several German research projects, which endeavour to analyse the relation between gender and inequality in dual career couples. 相似文献
340.
Harald Pühl 《Organisationsberatung, Supervision, Coaching》2005,12(3):245-252
From supervision to mediation and vice versaMediation in organizations becomes more and more important because of increasing conflicts. The question is, which competencies of the counsellor are necessary, and above all, whether mediation is a particular method. The author explains the method of mediation and illustrates his concept of “patchwork-mediation”. This procedure allows to build a bridge between supervision and mediation. 相似文献