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1.
Damage models for natural hazards are used for decision making on reducing and transferring risk. The damage estimates from these models depend on many variables and their complex sometimes nonlinear relationships with the damage. In recent years, data‐driven modeling techniques have been used to capture those relationships. The available data to build such models are often limited. Therefore, in practice it is usually necessary to transfer models to a different context. In this article, we show that this implies the samples used to build the model are often not fully representative for the situation where they need to be applied on, which leads to a “sample selection bias.” In this article, we enhance data‐driven damage models by applying methods, not previously applied to damage modeling, to correct for this bias before the machine learning (ML) models are trained. We demonstrate this with case studies on flooding in Europe, and typhoon wind damage in the Philippines. Two sample selection bias correction methods from the ML literature are applied and one of these methods is also adjusted to our problem. These three methods are combined with stochastic generation of synthetic damage data. We demonstrate that for both case studies, the sample selection bias correction techniques reduce model errors, especially for the mean bias error this reduction can be larger than 30%. The novel combination with stochastic data generation seems to enhance these techniques. This shows that sample selection bias correction methods are beneficial for damage model transfer.  相似文献   
2.
19世纪末20世纪初,马克思的思想就传入了中国,梁启超在传统大同思想与社会主义贯通中对它进行解读;早期国民党人在批判资本主义,建构民生主义中对它进行评价;无政府主义在反传统中认同马克思的共产主义。虽然各有局限性,但又各有自身的意义。以十月革命的经验解读马克思主义,遮蔽了对马克思思想早期传播的研究,研究马克思主义在中国的早期传播,对认识马克思主义中国化有重要意义。  相似文献   
3.
试论近中国茶馆的社会功能   总被引:4,自引:0,他引:4  
牛力 《东方论坛》2002,(3):42-46
在近代中国 ,茶馆与民众生活紧密相连 ,并承担着广泛而又复杂的社会功能。茶馆与民众的经济生活相关联 ,也是民间纠纷调解的重要场所。同时 ,作为一个公众活动的场所 ,茶馆也是民间社会信息传播的集散地 ;民众在茶馆中表达自己的见解 ,也使得茶馆成为一种控制舆论的力量。茶馆的这些功能是近代民间社会内在运作逻辑的体现。  相似文献   
4.
本文试图对帝国主义时代基督教在我国西南地区民族的传播情况加以论述,从而进一步探讨基督教在西南民族的传播轨迹以及对西南民族文化的影响。  相似文献   
5.
This paper reports on the mixing of Euro coins from different countries of origin in Europe, which started on 1 January 2002. There is an interesting conclusion: that the mobility of small and large denominations is different. The long‐term behaviour of the mixing process is studied using a simple deterministic model and data from Germany, France and the Netherlands. The analysis leads to predictions about the future progress of the mixing process.  相似文献   
6.
关于规范普通话水平测试工作的思考   总被引:1,自引:0,他引:1  
规范普通话水平测试工作 ,必须健全制度 ,建设好管理人员和测试人员队伍 ,并做好普通话培训、考务管理、测试等具体工作环节  相似文献   
7.
通过扩展基础加筋风积砂地基的室内模型上拔试验 ,研究了不同试验方案的加筋土体在极限上拔承载力 ,并提出了加筋风积砂土体的上拔承载力的理论计算公式  相似文献   
8.
乌鲁木齐市旅游产业关联和产业波及分析   总被引:4,自引:0,他引:4  
以乌鲁木齐市为例,利用投入产出表对旅游业的产业关联和产业波及效应作系统的定量分析,通过揭示旅游业的投入结构、中间需求率、中间投入率、旅游业的波及线路、影响力及影响力系数、感应度与感应度系数等重要指标,旨在为乌鲁木齐市的旅游经济研究提供有益的决策参考。  相似文献   
9.
Because of the inherent complexity of biological systems, there is often a choice between a number of apparently equally applicable physiologically based models to describe uptake and metabolism processes in toxicology or risk assessment. These models may fit the particular data sets of interest equally well, but may give quite different parameter estimates or predictions under different (extrapolated) conditions. Such competing models can be discriminated by a number of methods, including potential refutation by means of strategic experiments, and their ability to suitably incorporate all relevant physiological processes. For illustration, three currently used models for steady-state hepatic elimination--the venous equilibration model, the parallel tube model, and the distributed sinusoidal perfusion model--are reviewed and compared with particular reference to their application in the area of risk assessment. The ability of each of the models to describe and incorporate such physiological processes as protein binding, precursor-metabolite relations and hepatic zones of elimination, capillary recruitment, capillary heterogeneity, and intrahepatic shunting is discussed. Differences between the models in hepatic parameter estimation, extrapolation to different conditions, and interspecies scaling are discussed, and criteria for choosing one model over the others are presented. In this case, the distributed model provides the most general framework for describing physiological processes taking place in the liver, and has so far not been experimentally refuted, as have the other two models. These simpler models may, however, provide useful bounds on parameter estimates and on extrapolations and risk assessments.  相似文献   
10.
A quantitative criterion for ranking the different scenarios of nuclear and radiological terrorism has been developed. The aim of the model is not to predict terroristic events but only to indicate which scenario has the higher utility from the point of view of a terroristic organization in terms of balance between factors favoring and discouraging the attack, respectively. All these factors were quantified according to a scoring system that takes into account the logarithmic relationship between perceptions and stimuli. The criterion was applied to several scenarios, each of which was modeled in a simple but not trivial way in order to estimate the expected damage in terms of probable life losses from both radiative and nonradiative effects. The outcome from the ranking method indicates that the attractive scenario appears to be the detonation of a low yield improvised nuclear device in the metropolitan area of a major city.  相似文献   
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