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1.
随着公共文化服务水平与人民日益增长的物质文化需求之间矛盾的凸显,如何通过政策优化来提高公共文化服务水平成为人们日益关注的问题。通过建构“价值链-政策工具”二维分析框架,选择近10年中央层面公共文化服务政策文本,运用内容分析法,试图揭示我国公共文化服务政策工具的运行规律及其偏好,并提出政策路径优化建议。研究表明:在政策工具使用上,我国公共文化服务存在内部比例不均衡或不足情形,偏向于环境型政策工具,需求型政策工具使用比重较低;在价值链维度上,公共文化服务政策偏重于政府负责,市场配置、社会协同与公众参与等多元主体协作治理格局尚未形成。为此,应提升政策工具使用的均衡性,完善政策监督评价机制,构建以政府为主导,社会、市场、公众等多元主体协同参与的治理格局。  相似文献   
2.
实现脱贫攻坚与乡村振兴有效衔接,应准确把握“双循环”新发展格局“空间重构基础上要素组合优化和区域高质量发展”的战略要义。从减贫规律认知升华、行为外嵌转向发展自觉、资源配置优化与延续效应发挥三个层面分析脱贫攻坚与乡村振兴有效衔接行为的内在逻辑,厘清“双循环”新发展格局建设对于脱贫攻坚与乡村振兴有效衔接工作的机遇与挑战。提出应着力做好发展规划统筹、体制政策健全完善、产业转型升级、相对贫困治理、全域生态宜居环境创建、新时代文明实践中心高质量建设、乡村治理体系与治理能力现代化协同推进、城乡融合发展等领域工作,推进脱贫攻坚与乡村振兴有效衔接工作及其与“双循环”新发展格局建设的良性互动。  相似文献   
3.
This article proposes a novel mathematical optimization framework for the identification of the vulnerabilities of electric power infrastructure systems (which is a paramount example of critical infrastructure) due to natural hazards. In this framework, the potential impacts of a specific natural hazard on an infrastructure are first evaluated in terms of failure and recovery probabilities of system components. Then, these are fed into a bi‐level attacker–defender interdiction model to determine the critical components whose failures lead to the largest system functionality loss. The proposed framework bridges the gap between the difficulties of accurately predicting the hazard information in classical probability‐based analyses and the over conservatism of the pure attacker–defender interdiction models. Mathematically, the proposed model configures a bi‐level max‐min mixed integer linear programming (MILP) that is challenging to solve. For its solution, the problem is casted into an equivalent one‐level MILP that can be solved by efficient global solvers. The approach is applied to a case study concerning the vulnerability identification of the georeferenced RTS24 test system under simulated wind storms. The numerical results demonstrate the effectiveness of the proposed framework for identifying critical locations under multiple hazard events and, thus, for providing a useful tool to help decisionmakers in making more‐informed prehazard preparation decisions.  相似文献   
4.
复杂成形装备作为高端制造产业的基础装备,是各产业转型升级和技术进步的重要保障。同时快速发展的互联网与大数据等新兴信息技术已经成为装备制造业创新不可或缺的组成部分,极其深刻地影响着复杂成形装备产业的制造模式、发展战略以及产品的开发方式。本文研究了面向服务的复杂成形装备产品架构设计与优化方法。采用公理化设计的域结构思想,建立需求域、功能域和架构域之间的映射关系;提出了基于QFD的功能生成方法以及功能模型约简方法;利用DMM建立产品架构和服务架构之间的关联关系;利用模块化理论方法,并考虑成本因素对产品架构进行优化。  相似文献   
5.
ABSTRACT

Games can be a powerful tool for learning about statistical methodology. Effective game design involves a fine balance between caricature and realism, to simultaneously illustrate salient concepts in a controlled setting and serve as a testament to real-world applicability. Striking that balance is particularly challenging in response surface and design domains, where real-world scenarios often play out over long time scales, during which theories are revised, model and inferential techniques are improved, and knowledge is updated. Here, I present a game, borrowing liberally from one first played over 40 years ago, which attempts to achieve that balance while reinforcing a cascade of topics in modern nonparametric response surfaces, sequential design, and optimization. The game embeds a blackbox simulation within a shiny app whose interface is designed to simulate a realistic information–availability setting, while offering a stimulating, competitive environment wherein students can try out new methodology, and ultimately appreciate its power and limitations. Interface, rules, timing with course material, and evaluation are described, along with a “case study” involving a cohort of students at Virginia Tech. Supplementary materials for this article are available online.  相似文献   
6.
环境污染社会第三方治理研究   总被引:2,自引:0,他引:2  
环境污染风险具有流动性、不确定性、跨时空性、不可测量性及难以修复性特征,导致环境污染国家治理机制和环境污染市场治理机制存在制度性局限,亟须建构环境污染社会第三方治理机制。环保社会第三方具有公共性、公益性、专业性、中立性及组织性的特点,环境污染社会第三方治理能够实现利益诉求、利益发展、利益协调及利益保障的制度绩效。针对环境污染社会第三方治理面临的宏观权力结构性失衡、中观机制整体性失调、微观行为系统性失范等瓶颈,优化我国环境污染社会第三方治理的结构性均衡机制、整体性实施机制和系统性规范机制。  相似文献   
7.
Dominance hierarchies play an important role in governing the social interactions of humans and other species of social animals. In a social group, dominance relations can be inferred from the directed network of matchups between actors. Methodologists have proposed different ways to measure social dominance in directed networks. One such measure, the “β-measure” (van den Brink and Gilles, 2000), emphasizes the quality of defeated opponents in a way that an actor is seen as being more dominant when s/he defeats opponents who are more rarely defeated. While insightful in theory, the validity of the measure in people’s perception remains questionable, considering the cognitive complexity imposed by this measure, compared to a simpler measure that merely counts the number of defeated opponents. We conducted a vignette experiment with human subjects (professional athletes) to test their judgments of the dominance relation in a hypothetical tournament. Fitting our parametric model to peoples’ evaluations in the experiment, we found strong evidence in support of the β-measure: Although, in general, contestants who win more in the tournament are regarded as being more dominant, the contents of the winning records matter, such that those who beat more victorious opponents are further regarded as more dominant than those who defeat less victorious opponents. We also found a gender difference, in that men have a stronger propensity than women to adopt the β-measure when judging social dominance.  相似文献   
8.
在经典报童模型下考虑供应和需求不确定性,研究了具有风险厌恶的零售商库存优化问题。采用条件风险值(CVaR)对库存绩效进行度量,构建了基于CVaR的零售商库存运作模型;在此基础上,考虑上游供应商供货能力和下游市场需求不确定性,并采用一系列未知概率的离散情景进行描述,给出了供需不确定条件下基于CVaR的零售商库存鲁棒优化模型。进一步,采用区间不确定集对未知情景概率进行建模,给出了基于最大最小准则的鲁棒对应模型。针对同时考虑供需不确定性导致的模型非凸性,采用标准对偶理论将其转化为易于求解的数学规划问题。最后,通过数值计算分析了不同风险厌恶程度和不确定性程度对零售商库存决策以及库存绩效的影响。结果表明,供需不确定性的存在虽然会导致零售商库存绩效损失,但损失值较小。特别地,依据文中模型得到的鲁棒库存策略在多数情况下能够保证零售商获得更优的库存绩效。此外,不确定性和风险厌恶程度的增加虽然会影响零售商库存决策和运作绩效,但在同等风险厌恶态度下,随着不确定性程度的增加,基于文中方法得到的鲁棒库存策略仍能确保零售商获得理想的库存绩效,表明文中所建模型在应对供需不确定性方面具有良好的鲁棒性。  相似文献   
9.
Predicting the arrival time of a transit vehicle involves not only knowledge of its current position and schedule adherence, but also traffic conditions along the remainder of the route. Road networks are dynamic and can quickly change from free‐flowing to highly congested, which impacts the arrival time of transit vehicles, particularly buses which often share the road with other vehicles, so reliable predictions need to account for real‐time and future traffic conditions. The first step in this process is to construct a framework with which road state (traffic conditions) can be estimated using real‐time transit vehicle position data. Our proposed framework implements a vehicle model using a particle filter to estimate road travel times, which are used in a second model to estimate real‐time traffic conditions. Although development and testing took place in Auckland, New Zealand, we generalised each component to make the framework compatible with other public transport systems around the world. We demonstrate the real‐time feasibility and performance of our approach in real‐time, where a combination of R and C++ was used to obtain the necessary performance results. Future work will use these estimated traffic conditions in combination with historical data to obtain reliable arrival time predictions of transit vehicles.  相似文献   
10.
Abstract

This paper proposes a new mathematical model for the reliability-redundancy allocation problem (RRAP) with a choice of redundancy strategies. To maximize the reliability of a system, this model chooses the best redundancy strategy from among both active and standby ones for each subsystem. For those with a standby strategy, a continuous time Markov chain model is used to calculate the exact reliability values. In order to solve the proposed mixed-integer non-linear programing model, a powerful evolutionary algorithm, called water cycle algorithm (WCA), is developed and implemented on three famous benchmark problems. Finally, the results of different benchmark problems are compared with those previously reported to show the superiority of the proposed model and the efficiency of WCA.  相似文献   
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