全文获取类型
收费全文 | 2276篇 |
免费 | 76篇 |
国内免费 | 18篇 |
专业分类
管理学 | 379篇 |
民族学 | 9篇 |
人口学 | 208篇 |
丛书文集 | 114篇 |
理论方法论 | 147篇 |
综合类 | 1222篇 |
社会学 | 267篇 |
统计学 | 24篇 |
出版年
2024年 | 3篇 |
2023年 | 8篇 |
2022年 | 8篇 |
2021年 | 14篇 |
2020年 | 35篇 |
2019年 | 44篇 |
2018年 | 40篇 |
2017年 | 77篇 |
2016年 | 78篇 |
2015年 | 77篇 |
2014年 | 128篇 |
2013年 | 255篇 |
2012年 | 122篇 |
2011年 | 155篇 |
2010年 | 139篇 |
2009年 | 131篇 |
2008年 | 140篇 |
2007年 | 164篇 |
2006年 | 149篇 |
2005年 | 139篇 |
2004年 | 94篇 |
2003年 | 77篇 |
2002年 | 82篇 |
2001年 | 79篇 |
2000年 | 49篇 |
1999年 | 24篇 |
1998年 | 8篇 |
1997年 | 11篇 |
1996年 | 5篇 |
1995年 | 8篇 |
1994年 | 3篇 |
1993年 | 7篇 |
1992年 | 4篇 |
1991年 | 2篇 |
1990年 | 4篇 |
1989年 | 3篇 |
1988年 | 2篇 |
1987年 | 1篇 |
1983年 | 1篇 |
排序方式: 共有2370条查询结果,搜索用时 46 毫秒
31.
《Omega》2017
Tactical production-distribution planning models have attracted a great deal of attention in the past decades. In these models, production and distribution decisions are considered simultaneously such that the combined plans are more advantageous than the plans resolved in a hierarchical planning process. We consider a two-stage production process, where in the first stage raw materials are transformed into continuous resources that feed the discrete production of end products in the second stage. Moreover, the setup times and costs of resources depend on the sequence in which they are processed in the first stage. The minimum scheduling unit is the product family which consists of products sharing common resources and manufacturing processes. Based on different mathematical modelling approaches to the production in the first stage, we develop a sequence-oriented formulation and a product-oriented formulation, and propose decomposition-based heuristics to solve this problem efficiently. By considering these dependencies arising in practical production processes, our model can be applied to various industrial cases, such as the beverage industry or the steel industry. Computation tests on instances from an industrial application are provided at the end of the paper. 相似文献
32.
Extreme and catastrophic events pose challenges for normative models of risk management decision making. They invite development of new methods and principles to complement existing normative decision and risk analysis. Because such events are rare, it is difficult to learn about them from experience. They can prompt both too little concern before the fact, and too much after. Emotionally charged and vivid outcomes promote probability neglect and distort risk perceptions. Aversion to acting on uncertain probabilities saps precautionary action; moral hazard distorts incentives to take care; imperfect learning and social adaptation (e.g., herd‐following, group‐think) complicate forecasting and coordination of individual behaviors and undermine prediction, preparation, and insurance of catastrophic events. Such difficulties raise substantial challenges for normative decision theories prescribing how catastrophe risks should be managed. This article summarizes challenges for catastrophic hazards with uncertain or unpredictable frequencies and severities, hard‐to‐envision and incompletely described decision alternatives and consequences, and individual responses that influence each other. Conceptual models and examples clarify where and why new methods are needed to complement traditional normative decision theories for individuals and groups. For example, prospective and retrospective preferences for risk management alternatives may conflict; procedures for combining individual beliefs or preferences can produce collective decisions that no one favors; and individual choices or behaviors in preparing for possible disasters may have no equilibrium. Recent ideas for building “disaster‐resilient” communities can complement traditional normative decision theories, helping to meet the practical need for better ways to manage risks of extreme and catastrophic events. 相似文献
33.
关于我国的城市规划管理权限一直存在"集中"与"放权"的讨论,并且城市规划管理体制也存在差异。通过对全国部分城市的规划管理体制进行梳理,从市、区(县、市)两级分权视角总结出我国城市规划管理体制中的"垂直型"、"半垂直型"和"非垂直型"三种典型模式,分别以南京、北京和上海为案例分析三种规划管理体制典型模式的主要特点和事权划分,并对其各自的优缺点进行比较,最后提出我国城市规划管理体制改革的若干建议,包括将规划决策权"上收"与实施管理重心"下移"、建立"市—区—镇(街)"三级规划管理机构体系、整合市区两级规划部门内部机构设置形成"大处室"和"大科室"以及完善城市规划委员会制度等。 相似文献
34.
In electronics Fabs such as semiconductor Fabs and liquid crystal display (LCD) Fabs, which are capital-intensive, finite-capacity planning is critical to achieving full-capacity production and on-time production. However, existing finite-capacity planning methods do not adequately reflect the actual capacity profiles of an electronics Fab. In this paper, we propose a new Fab-level capacity-filtering procedure to generate finite-capacity plan: a backward capacity-filtering procedure for generating finite-capacity release plan. When developing the Fab-level filtering procedures, we use stage-level capacity-filtering algorithms as a key building block. In this study, we enhance the previous capacity-filtering algorithms proposed by one of the authors in order to facilitate the practical requirements of electronics Fabs. We apply the proposed capacity-filtering method to a modern LCD–TFT Fab in Korea. Performance analyses demonstrate that the proposed method is superior to existing methods. 相似文献
35.
This paper discusses the extent to which topical planning issues of informality and illegality are incorporated into the educational curricula in Nigerian planning schools. Given the scale and enormity of informal and illegal settlements in Nigeria and other African cities, these issues should be emphasized in the education and training of planning professionals. Yet, few curricula in Nigerian planning schools, including the Nigerian Town Planners Registration Council’s professional curriculum, incorporate informal urban issues. The paper recommends an educational interventionist approach based on recognition of the potential of indigenous knowledge as a means of producing critical and reflective planning graduates who possess the competencies to deal with contemporary settlement challenges. It presents the institutional landscape for planning education and the processes of planning curricular reform and accreditation with a view to revitalizing planning education in Nigeria. 相似文献
36.
37.
We urgently need to put the concept of resilience into practice if we are to prepare our communities for climate change and exacerbated natural hazards. Yet, despite the extensive discussion surrounding community resilience, operationalizing the concept remains challenging. The dominant approaches for assessing resilience focus on either evaluating community characteristics or infrastructure functionality. While both remain useful, they have several limitations to their ability to provide actionable insight. More importantly, the current conceptualizations do not consider essential services or how access is impaired by hazards. We argue that people need access to services such as food, education, health care, and cultural amenities, in addition to water, power, sanitation, and communications, to get back some semblance of normal life. Providing equitable access to these types of services and quickly restoring that access following a disruption are paramount to community resilience. We propose a new conceptualization of community resilience that is based on access to essential services. This reframing of resilience facilitates a new measure of resilience that is spatially explicit and operational. Using two illustrative examples from the impacts of Hurricanes Florence and Michael, we demonstrate how decisionmakers and planners can use this framework to visualize the effect of a hazard and quantify resilience-enhancing interventions. This “equitable access to essentials” approach to community resilience integrates with spatial planning, and will enable communities not only to “bounce back” from a disruption, but to “bound forward” and improve the resilience and quality of life for all residents. 相似文献
38.
Arturo Orellana Federico Arenas Catalina Marshall Alvaro Rivera 《Planning Practice and Research》2016,31(4):435-451
In this article, the authors review and analyse two key processes conducted by the Chilean state over the past 50 years. The first process consists of the development of specific planning instruments for the particular realities of metropolitan areas. The second process consists of the successive legislative attempts to work towards a definition of a new form of institutionality for cities with metropolitan profiles. These attempts have either failed or solely become bills of law. Both processes suggest a political and technical resistance throughout history, to substantially modify institutionality, as well as planning instruments, in order to make them more appropriate and consistent with the needs of growing metropolitan areas in Chile. 相似文献
39.
《Journal of gerontological social work》2012,55(8):912-929
ABSTRACTPeople are living and driving longer than ever before, with little preparation for transitioning to being non-drivers. We investigated driving expectations among drivers age 65 and older, including sociodemographic and driving context predictors. Cross-sectional data from 349 older drivers were explored to determine variation in how many years they expected to continue driving. General linear models examined predictors of both expectations. In this predominantly Black/African American sample, 76% of older drivers (mean age = 73 ± 5.7 years) expected a non-driving future, forecasting living an average of 5.75 ± 7.29 years after driving cessation. Regression models on years left of driving life and years left to live post-driving cessation predicted nearly half of the variance in older drivers’ expectations with five significant predictors: income, current age, age expected to live to, self-limiting driving to nearby places and difficulty, visualizing being a non-driver. Many older drivers expect to stop driving before end of life. 相似文献
40.