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   251篇
  免费   8篇
管理学   61篇
民族学   6篇
人口学   25篇
丛书文集   1篇
理论方法论   10篇
综合类   2篇
社会学   102篇
统计学   52篇
  2023年   3篇
  2022年   2篇
  2021年   4篇
  2020年   9篇
  2019年   12篇
  2018年   17篇
  2017年   14篇
  2016年   16篇
  2015年   5篇
  2014年   15篇
  2013年   43篇
  2012年   26篇
  2011年   8篇
  2010年   10篇
  2009年   6篇
  2008年   11篇
  2007年   8篇
  2006年   2篇
  2005年   6篇
  2004年   3篇
  2003年   3篇
  2002年   3篇
  2001年   5篇
  2000年   2篇
  1999年   3篇
  1998年   2篇
  1997年   5篇
  1995年   1篇
  1994年   1篇
  1993年   3篇
  1992年   3篇
  1989年   1篇
  1988年   2篇
  1987年   3篇
  1986年   1篇
  1974年   1篇
排序方式: 共有259条查询结果,搜索用时 812 毫秒
131.
Data from 690 persons in three adult age groups were used to evaluate the generality of a componential model of happiness (Kozma et al., 1990). The model postulates that long- and short-term affective states combine in an additive manner to produce current happiness. The short-term components should be more susceptible to environmental manipulation than the long-term ones and should change more readily with an appropriate experimental manipulation. Subscales of the Memorial University Mood Scale (MUMS) were used to assess short-term affect while the experience subscales of the Memorial University of Newfoundland Scale of Happiness (MUNSH) and Diener's Long-term Satisfaction Scale were used to measure long-term affect. Overall current happiness was assessed by a seven-point avowed happiness rating scale. The Velten mood induction procedure was used to manipulate current affective state. In five of six comparisons, changes on short-term components were significantly greater than on long-term components. Age differences in reactivity to mood induction emerged only when a negative induction procedure was followed by a positive one. Under these conditions, the youngest cohort responded more consistently than the oldest cohort. An additive model, based on long- and short-term affect, age, and sex produced the best explanation for current happiness.  相似文献   
132.
As part of a larger operations research project, this 1990 study analyzed the performance of the Philippine Department of Health's (DOH) family planning (FP) clinics. Specific study objectives were 1) to measure acceptor targets, servicing capacity utilization, outreach, and costs; 2) to determine what providers believed affected performance; 3) to record which quality indicator providers use; and 4) to determine the perceptions of acceptors about clinic personnel, the clinic as a FP outlet, FP service processing, and FP service quality. Data were gathered from clinic records and from sample surveys in 25 clinics in four specified locations. Eight clients were sampled from each of the 100 clinics. It was found that clinic staff accepted low attainment of FP acceptor targets and that clinic capacity utilization levels were at 25% of capacity. Providers were unaware of the number of potential FP acceptors in their areas and had no information about the costs of running their clinics. The FP clinic managers identified 34 major determinants of clinic performance, but more than half reported that they had very little control over these determinants. The providers described quality service from the point of view of the acceptors and described the quality of a clinic in terms of the minimal physical characteristics required. The acceptor survey revealed that acceptor satisfaction depends upon 1) clinic accessibility and lay-out, 2) intensive personal contact, and 3) clinic infrastructure. The study uncovered a need for the DOH to institute management training programs for clinic managers and to provide managers with the resources and personnel to shift priorities in favor of FP coverage and prevalence. Managers, who are resource allocators, must also receive information about the costs of FP services in their clinics. In addition, the DOH's determination that its FP program would be facility- rather than community-based should be modified to incorporate community outreach elements. The DOH can also make a big impact on perceptions of quality (of both providers and acceptors) by improving clinic conditions to meet basic standards. Once these basic needs are met, additional needs of acceptors can and must be addressed.  相似文献   
133.
There is a wide sociological debate that documents how inattention, hyperactivity, and impulsive behaviours from a certain point forward cease to be disturbing behaviours and become childhood psychiatric disorders—named attention deficit/hyperactivity disorders (ADHD)—to be responded to with specific treatments since these behaviours are supposed to have a negative or pervasive impact on social and personal functioning and quality of life. Looking back over the stages of this debate, the article will focus on what, in recent years, are the two main directions of the expansion of the domain of medicalisation: on the one hand, discussing how the ADHD category has changed by moving from being typically a childhood problem to a disorder that can affect adults and, on the other, how it tends to globalise conquering new markets outside the United States, Canada, and Australia. The article concludes commenting on how the processes of lifelong expansion and worldwide diffusion is universalising the medical category, overcoming the disciplinary and geographical boundaries in which ADHD was created and developed.  相似文献   
134.
The textile sector is composed of small and medium enterprises (SMEs) worldwide. Nowadays there is a shortage of technological knowledge in SMEs. Lead time is a critical indicator in any productive company organisation. The aim of this research was to provide an approach, called REDUTEX, based on theoretical concepts of lean and synchronous manufacturing in order to help to understand the behaviour of SMEs and to improve the manufacturing process by reducing the customer lead times. The integration of these philosophies is the basis of REDUTEX; a hybrid push–pull production system approach to knitting SMEs. With this approach, it is possible to obtain a process reliability when the restrictive resource capacity (RRC) is identified, optimised and protected. By synchronising all activities to the rhythm of RRC, through a continuous flow, it is possible to obtain high-impact results through a dual automated system and product quality, through a visual control. REDUTEX uses a push system from the RRC to the location of the supermarket, where accumulated inventory may be distributed in the internal assembly department and external family workshops, making a pull system. Subsequent re-assembly processes use a push system until the end of the product. The stages of REDUTEX are explicitly described and applied to real data, so that the staff of SMEs can easily understand the behaviour of the process and implement it. One of the advantages of REDUTEX is that it does not need highly trained staff. The research methodology was conducted as a case of study in twelve SMEs and validated and implemented in three textile companies of the southern area of the state of Guanajuato in Mexico, obtaining reliable delivery times and very promising results.  相似文献   
135.
Our concern is the extension of the theory of the Shapley value to problems involving externalities. Using the standard axiom systems behind the Shapley value leads to the identification of bounds on players' payoffs around an “externality‐free” value. The approach determines the direction and maximum size of Pigouvian‐like transfers among players, transfers based on the specific nature of externalities that are compatible with basic normative principles. Examples are provided to illustrate the approach and to draw comparisons with previous literature.  相似文献   
136.
We prove existence of equilibrium in a continuous‐time securities market in which the securities are potentially dynamically complete: the number of securities is at least one more than the number of independent sources of uncertainty. We prove that dynamic completeness of the candidate equilibrium price process follows from mild exogenous assumptions on the economic primitives of the model. Our result is universal, rather than generic: dynamic completeness of the candidate equilibrium price process and existence of equilibrium follow from the way information is revealed in a Brownian filtration, and from a mild exogenous nondegeneracy condition on the terminal security dividends. The nondegeneracy condition, which requires that finding one point at which a determinant of a Jacobian matrix of dividends is nonzero, is very easy to check. We find that the equilibrium prices, consumptions, and trading strategies are well‐behaved functions of the stochastic process describing the evolution of information. We prove that equilibria of discrete approximations converge to equilibria of the continuous‐time economy.  相似文献   
137.
138.
The procedure of on-line process control for variables proposed by Taguchi consists of inspecting the mth item (a single item) of every m items produced and deciding, at each inspection, whether the mean value is increased or not. If the value of the monitored statistic is outside of the control limits, one decides the process is out-of-control and the production is stopped for adjustment; otherwise, it continues. In this article, a variable sampling interval (with a longer L and a shorter m ≤ L) chart with two set of limits is used. These limits are the warning (±W) and the control (±C), where W ≤ C. The process is stopped for adjustment when an observation falls outside of the control limits or a sequence of h observations falls between the warning limits and the control limits. The longer sample interval is used after an adjustment or when an observation falls inside the warning limits; otherwise, the short sampling interval is used. The properties of an ergodic Markov chain are used to evaluate the time (in units) that the process remains in-control and out-of-control, with the aim of building an economic–statistical model. The parameters (the sampling intervals m and L, the control limits W and C and the length of run h) are optimized by minimizing the cost function with constraints on the average run lengths (ARLs) and the conformity fraction. The performance of the current proposal is more economical than the decision taken based on a sequence of length h = 1, L = m, and W = C, which is the model employed in earlier studies. A numerical example illustrates the proposed procedure.  相似文献   
139.
The nonlinear filters based on Taylor series approximation are broadly used for computational simplicity, even though their filtering estimates are clearly biased. In this paper, first, we analyze what is approximated when we apply the expanded nonlinear functions to the standard linear recursive Kalman filter algorithm. Next, since the state variable αt and αt-t are approximated as a conditional normal distribution given information up to time t - 1 (i.e., It-1) in approximation of the Taylor series expansion, it might be appropriate to evaluate each expectation by generating normal random numbers of αt and αt-1 given It-1 and those of the error terms θ and ηt. Thus, we propose the Monte-Carlo simulation filter using normal random draws. Finally we perform two Monte-Carlo experiments, where we obtain the result that the Monte-Carlo simulation filter has a superior performance over the nonlinear filters such as the extended Kalman filter and the second-order nonlinear filter.  相似文献   
140.
The European Union Statistics on Income and Living Conditions (EU-SILC) is the main source of information about poverty and economic inequality in the member states of the European Union. The sample sizes of its annual national surveys are sufficient for reliable estimation at the national level but not for inferences at the sub-national level, failing to respond to a rising demand from policy-makers and local authorities. We provide a comprehensive map of median income, inequality (Gini coefficient and Lorenz curve) and poverty (poverty rates) based on the equivalised household income in the countries in which the EU-SILC is conducted. We study the distribution of income of households (pro-rated to its members), not merely its median (or mean), because we regard its dispersion and frequency of lower extremes (relative poverty) as important characteristics. The estimation for the regions with small sample sizes is improved by the small-area methods. The uncertainty of complex nonlinear statistics is assessed by bootstrap. Household-level sampling weights are taken into account in both the estimates and the associated bootstrap standard errors.  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