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1.
围绕中国碳中和目标的实现路径与模式选择问题,提出了一个中国应对气候变化整体治理模式,即多阶段混合主导型碳中和实现模式。这一模式是以国家为核心,在一定时期和内外环境约束下,通过减排和增汇路径,对中国境内由人类活动造成的CO2排放与人为CO2吸收量之间关系进行调整和平衡的过程;其内部由宏观、中观和微观三层结构组成,每层结构各不相同。多阶段混合主导型碳中和实现模式的提出,拓展和完善了气候变化整体治理理论,为气候变化治理提供了机制借鉴。  相似文献   
2.
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   
3.
Placement of refugees and subsequent labour market integration within a host country represents a key challenge for policymakers and has emerged as one of the most divisive topics in the public debate. Immigration policy in Switzerland adopts random placement of asylum seekers across its different language regions. Hence, this policy allows to estimate the causal effect of language skills on employment chances, as refugees are exogenously placed across regions where the spoken language could either match or deviate from individual language skills. The results of this ‘natural experiment’ indicate substantially higher probabilities of finding employment when asylum seekers are placed in regions with a lingua franca that matches their individual language skills. Additionally, the findings suggest that language course participation can offset the reduced likelihood of employment in cases of a language mismatch. While random placement of refugees may be desirable for political reasons, it is detrimental to the economic integration process. Thereby, the study draws relevant conclusions for a larger European immigration policy.  相似文献   
4.
目前,我国在页岩气开发的环境保护方面存在着大量的法律空白,往往只能参照环境保护法和矿产资源法中的相关规定进行规制,无法有效解决页岩气开发暴露出来的环境问题。页岩气开发环境风险的法律规制,核心目的就是解决当前页岩气开发中的环境风险,促进页岩气开发与环境保护相协调,实现能源开发的可持续发展。在页岩气开发环境风险的法律规制方面,英美两国已经探索出一些经验和制度。积极借鉴国外有益经验,努力改进和完善我国应对页岩气开发环境风险的法律规制,对实现我国页岩气开采的经济效益、社会效益和环境效益三者的统一具有重要的现实意义。  相似文献   
5.
Previous research has evaluated public risk perception and response to a natural hazards in various settings; however, most of these studies were conducted either with a single scenario or after a natural disaster struck. To better understand the dynamic relationships among affect, risk perception, and behavioral intentions related to natural disasters, the current study implements a simulation scenario with escalating weather intensity, and includes a natural experiment allowing comparison of public response before and after a severe tornado event with extensive coverage by the national media. The current study also manipulated the display of warning information, and investigated whether the warning system display format influences public response. Results indicate that (1) affect, risk perception, and behavioral intention escalated as weather conditions deteriorated, (2) responses at previous stages predicted responses at subsequent stages of storm progression, and (3) negative affect predicted risk perception. Moreover, risk perception and behavioral intention were heightened after exposure to the media coverage of an actual tornado disaster. However, the display format manipulation did not influence behavioral responses. The current study provides insight regarding public perception of predisaster warnings and the influence of exposure to media coverage of an actual disaster event.  相似文献   
6.
分析了常规油田开发模型所存在的问题;探讨了应用神经网络技术进行油气产量历史预测的可行性。油田实际资料验证评价结果表明:该法模拟预测精度高,效果好,简单实用,不失为油气产量动态预测的一条新途径。  相似文献   
7.
大自然是色彩的宝库,是幼儿自然色彩教育的最好课堂。幼儿自然色彩教育的根本目的不是掌握色彩知识或技巧, 而是通过大自然丰富多彩的色彩美激发幼儿对自然美的敏感性、好奇心,培养幼儿的审美素质,萌发幼儿热爱自然的情感,培 养幼儿健全的生命意识。幼儿自然色彩教育应让幼儿面对活的、灵动的自然色彩,在自然情境中唤醒幼儿的色彩敏锐性,激 活幼儿对美的感受力,让幼儿在一花一草的色彩变化中体悟一种生命滋养另一种生命的神奇,感悟生命的真谛,从而学会感 恩自然。  相似文献   
8.
This article presents methodological solutions aimed at presenting the spatial distribution of flood risk and quality of spatial management (land use), indicating both those areas used reasonably and those requiring modification. The purpose was to identify key risk areas and risk‐free areas from the point of view of human security and activity on the floodplains, based on the examples of the vicinities of Wroclaw and Raciborz in the Odra Valley, Poland. Due to recent climate change, Poland has suffered the effects of severe flooding (e.g., 1997, 2001, 2010). The analyses conducted were motivated by the European Parliament and Council's recently implemented Directive 2007/60/WE, as well as by the demand for studies for local spatial planning. The analysis indicates that reasonably developed areas do not account for the majority of those studied, making up 36% of the Wroclaw area and 15% of the Raciborz area.  相似文献   
9.
刘庆邦柔美小说主要有两种情感脉络,纯真的情感和温柔细腻、含蓄委婉的情感表达方式,小说中忧伤的情调和自然的境界,蕴涵的审美情趣和审美理想切合90年代兴起的怀旧思潮,表现了作者对抗工业文明、呼唤诗性生命的批判立场。对于生态失衡的现代社会和人的精神处境,刘庆邦的柔美小说是一缕来自田野的风,它的清新足以澡雪精神,吹散物欲膨胀的燥热,召唤久违的自然之美重新回到人类的心田。  相似文献   
10.
实现农户风险管理意愿与行为统一是降低农业风险对农户农业生产负面影响的重要途径。利用2018年东北三省和湖北省种植大户的调查数据,从自然风险与市场风险两方面,对农户风险管理的意愿、行为及其悖离进行分析,并探究形成悖离的原因。研究发现:对于自然风险,大部分农户使用了有效的风险管理工具,但风险管理意愿不高;农户的市场风险管理行为极为少见,与之相悖的是,农户具有较高的市场风险管理意愿。结果表明,风险管理实际行为控制、风险管理执行意愿和风险管理外部环境是影响农户自然风险管理意愿与行为悖离的主要因素;此外,农户对农业保险缺乏了解,以及目前农业保险存在的不足也是导致此悖离的重要原因;风险管理执行意愿和风险管理外部环境是影响农户市场风险管理意愿与行为悖离的主要因素。此外,农户获取信息渠道不足,对市场风险管理工具缺乏了解,甚至存在明显的误解与不信任也是导致农户市场风险管理意愿与行为悖离的重要原因。因此,为了有效实现农户风险管理意愿与行为的统一,应健全农业保险的推广机制,加强市场风险管理的宣传,扩大“保险+期货”的试点,发挥新型主体的带动作用。  相似文献   
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