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   141篇
  免费   2篇
管理学   24篇
民族学   1篇
人口学   8篇
理论方法论   4篇
社会学   32篇
统计学   74篇
  2022年   3篇
  2021年   2篇
  2020年   9篇
  2019年   14篇
  2018年   10篇
  2017年   18篇
  2016年   9篇
  2015年   6篇
  2014年   6篇
  2013年   25篇
  2012年   5篇
  2011年   7篇
  2010年   1篇
  2009年   4篇
  2008年   2篇
  2007年   5篇
  2005年   1篇
  2004年   1篇
  2003年   1篇
  2002年   2篇
  2001年   1篇
  2000年   1篇
  1999年   3篇
  1998年   2篇
  1997年   2篇
  1996年   2篇
  1995年   1篇
排序方式: 共有143条查询结果,搜索用时 15 毫秒
111.
112.
This article offers a comparative analysis between the ideological orientation of structural social work (SSW) and the programmatic orientation of the Bangladesh Rural Advancement Committee (BRAC). SSW sees social problems as arising from specific socio-economic contexts rather than from the failings of individuals. This perspective recognises that patriarchy is a central feature of life in Bangladesh. BRAC analyses poverty, broadly defined, from a perspective that is political, making use of feminist principles. By assessing SSW as it pertains to the programme coverage of BRAC, this article presents the consistencies and inconsistencies of the approaches. Yet, SSW and BRAC share a common objective of shifting the locus of power to facilitate the empowerment of marginalised communities.  相似文献   
113.
We consider the distribution planning problem in the motion picture industry. This problem involves forecasting theater‐level box office revenues for a given movie and using these forecasts to choose the best locations to screen a movie. We first develop a method that predicts theater‐level box office revenues over time for a given movie as a function of movie attributes and theater characteristics. These estimates are then used by the distributor to choose where to screen the movie. The distributor's location selection problem is modeled as an integer programming‐based optimization model that chooses the location of theaters in order to optimize profits. We tested our methods on realistic box office data and show that it has the potential to significantly improve the distributor's profits. We also develop some insights into why our methods outperform existing practice, which are crucial to their successful practical implementation.  相似文献   
114.
The axiom of weak disposability is frequently imposed in data envelopment analysis (DEA) models involving undesirable outputs such as pollution. This paper sheds new light on the economic interpretation of weak disposability by developing dual formulations of the weakly disposable DEA technology. We find that the economic implications of weak disposability on the multiplier DEA problem are two-fold: (1) the shadow prices of the undesirable outputs can be positive or negative, and (2) the economic loss of the benchmark cannot exceed the suck cost of the inputs. We interpret the second implications as a limited liability condition. The dual formulations developed in this paper enable one to estimate shadow prices of the undesirable outputs using the weakly disposable technology. The insights gained are illustrated by a numerical example and an empirical application to the US power plants.  相似文献   
115.
The procedure developed by Muckstadt and Roundy is generalized. In a multi-echelon inventory system with a single warehouse and multi-retailers, some di erent items with constant demand rates are distributed. Considering set-up and holding costs as well as the cost of joint shipment of items from the warehouse to any retailer, the objective is to minimize the total costs of the system. In the proposed algorithm the assumption of nested policies is relaxed. The procedure introduced works for both nested and non-nested policies.  相似文献   
116.
Organisations willing to succeed in global competition have to integrate their internal and external processes. This especially includes planning and production control (PPC) processes. Optimised allocation of the production resources and quick response to demand changes result in lower cost and improvement of production performance. Practitioners and researchers have been trying to achieve these goals using production planning techniques. Although the results are significant, it seems necessary to integrate production operations in order to improve the production performance. The goals, information and decisions taken in production planning and control and process planning are often very different and difficult to integrate in Cellular Manufacturing (CM) environments. Designing an efficient PPC system and integrating it with process planning in a cellular environment is of the same importance. The following paper proposes first a comprehensive framework of integrated process planning and production planning and control in CM. Then, with respect to this framework and utilising the domain knowledge in the area of CM systems, an integrated model based on Integrated Definition Modeling Language is developed. The application of the models has been considered as a case study for a production system in electronics and telecommunication sector in a plant in Iran. The validity and completeness of the proposed model is tested by a panel of experts in the areas of production planning and control in CM environments.  相似文献   
117.
In this paper we give improved approximation algorithms for some network design problems. In the bounded-diameter or shallow-light \(k\)-Steiner tree problem (SL\(k\)ST), we are given an undirected graph \(G=(V,E)\) with terminals \(T\subseteq V\) containing a root \(r\in T\), a cost function \(c:E\rightarrow \mathbb {R}^+\), a length function \(\ell :E\rightarrow \mathbb {R}^+\), a bound \(L>0\) and an integer \(k\ge 1\). The goal is to find a minimum \(c\)-cost \(r\)-rooted Steiner tree containing at least \(k\) terminals whose diameter under \(\ell \) metric is at most \(L\). The input to the buy-at-bulk \(k\)-Steiner tree problem (BB\(k\)ST) is similar: graph \(G=(V,E)\), terminals \(T\subseteq V\) containing a root \(r\in T\), cost and length functions \(c,\ell :E\rightarrow \mathbb {R}^+\), and an integer \(k\ge 1\). The goal is to find a minimum total cost \(r\)-rooted Steiner tree \(H\) containing at least \(k\) terminals, where the cost of each edge \(e\) is \(c(e)+\ell (e)\cdot f(e)\) where \(f(e)\) denotes the number of terminals whose path to root in \(H\) contains edge \(e\). We present a bicriteria \((O(\log ^2 n),O(\log n))\)-approximation for SL\(k\)ST: the algorithm finds a \(k\)-Steiner tree with cost at most \(O(\log ^2 n\cdot \text{ opt }^*)\) where \(\text{ opt }^*\) is the cost of an LP relaxation of the problem and diameter at most \(O(L\cdot \log n)\). This improves on the algorithm of Hajiaghayi et al. (2009) (APPROX’06/Algorithmica’09) which had ratio \((O(\log ^4 n), O(\log ^2 n))\). Using this, we obtain an \(O(\log ^3 n)\)-approximation for BB\(k\)ST, which improves upon the \(O(\log ^4 n)\)-approximation of Hajiaghayi et al. (2009). We also consider the problem of finding a minimum cost \(2\)-edge-connected subgraph with at least \(k\) vertices, which is introduced as the \((k,2)\)-subgraph problem in Lau et al. (2009) (STOC’07/SICOMP09). This generalizes some well-studied classical problems such as the \(k\)-MST and the minimum cost \(2\)-edge-connected subgraph problems. We give an \(O(\log n)\)-approximation algorithm for this problem which improves upon the \(O(\log ^2 n)\)-approximation algorithm of Lau et al. (2009).  相似文献   
118.
Compliance with one specified dosing strategy of assigned treatments is a common problem in randomized drug clinical trials. Recently, there has been much interest in methods used for analysing treatment effects in randomized clinical trials that are subject to non-compliance. In this paper, we estimate and compare treatment effects based on the Grizzle model (GM) (ignorable non-compliance) as the custom model and the generalized Grizzle model (GGM) (non-ignorable non-compliance) as the new model. A real data set based on the treatment of knee osteoarthritis is used to compare these models. The results based on the likelihood ratio statistics and simulation study show the advantage of the proposed model (GGM) over the custom model (GGM).  相似文献   
119.
120.
Among the changes in the field of community development is thegrowing importance of microfinance, both to provide access tocredit and as a vehicle for empowerment. Community banks arerecognized for their role in meeting these goals, although theyremain controversial, as the goals of microfinance are not alwaysagreed upon, with government officials and community membersemphasizing different interests. We examine the Los AngelesCommunity Development Bank to glean further lessons regardingthe role community banks can play in community development.Among the lessons from this experience are that politics areinescapable in the design of community banks; the economicsof banking tends to undervalue community needs; and culturalfactors include both professional and community-level challenges.Accounting for these factors can help community banks empowercommunities to meet the challenges of eliminating poverty.  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