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141.
Participants were 109 American college students studying Chinese in a study-abroad programme in Beijing. Following Kelley and Meyer, intercultural competence was defined as cross-cultural adaptability involving four dimensions (emotional resilience, flexibility/openness, perceptual acuity and personal autonomy) and was measured with a survey. A language contact questionnaire was used to document the amount of time spent on social activities. Language proficiency was measured with a standardised Chinese test. Results revealed that intercultural competence and language contact combined explained 37.7% of the proficiency gains. Language contact had direct effects on proficiency, but intercultural competence had indirect effects, mediated by language contact.  相似文献   
142.
ABSTRACT

In this paper, we propose an adaptive stochastic gradient boosting tree for classification studies with imbalanced data. The adjustment of cost-sensitivity and the predictive threshold are integrated together with a composite criterion into the original stochastic gradient boosting tree to deal with the issues of the imbalanced data structure. Numerical study shows that the proposed method can significantly enhance the classification accuracy for the minority class with only a small loss in the true negative rate for the majority class. We discuss the relation of the cost-sensitivity to the threshold manipulation using simulations. An illustrative example of the analysis of suboptimal health-state data in traditional Chinese medicine is discussed.  相似文献   
143.
The main purpose of dose‐escalation trials is to identify the dose(s) that is/are safe and efficacious for further investigations in later studies. In this paper, we introduce dose‐escalation designs that incorporate both the dose‐limiting events and dose‐limiting toxicities (DLTs) and indicative responses of efficacy into the procedure. A flexible nonparametric model is used for modelling the continuous efficacy responses while a logistic model is used for the binary DLTs. Escalation decisions are based on the combination of the probabilities of DLTs and expected efficacy through a gain function. On the basis of this setup, we then introduce 2 types of Bayesian adaptive dose‐escalation strategies. The first type of procedures, called “single objective,” aims to identify and recommend a single dose, either the maximum tolerated dose, the highest dose that is considered as safe, or the optimal dose, a safe dose that gives optimum benefit risk. The second type, called “dual objective,” aims to jointly estimate both the maximum tolerated dose and the optimal dose accurately. The recommended doses obtained under these dose‐escalation procedures provide information about the safety and efficacy profile of the novel drug to facilitate later studies. We evaluate different strategies via simulations based on an example constructed from a real trial on patients with type 2 diabetes, and the use of stopping rules is assessed. We find that the nonparametric model estimates the efficacy responses well for different underlying true shapes. The dual‐objective designs give better results in terms of identifying the 2 real target doses compared to the single‐objective designs.  相似文献   
144.
动物和人一样,也具有不同的秉性。以动物喻人,自古即有。从辩证的角度看,动物秉性自然有好的一面,也有坏的一面。这里我们借助动物思考人生,专门探讨动物秉性中一些好的品质,狗-无比忠诚;猪-难得糊涂;狼-勇敢合作的典范;牛-勤劳奉献精神;狐狸-聪明智慧的象征;龟-勤恳踏实的榜样。可见,动物的许多秉性亦给人生带来诸多的启示,值得人们以思考和学习。  相似文献   
145.
Abstract

This study examines the commitment of social work in various countries to its declared dual missionenhancing individual well-being and promoting social justice. It does so by examining the mode of practice preferences of graduating BSW students from seven countries. Based on cluster analysis, three distinct subgroups of students with particular patterns of preferences were found: a generic group, a direct/micro group, and a macro group. The distribution of students among these groups differs between country cohorts. While each of the clusters was to be found in all the countries studied, in three country cohorts, a majority of students belonged to the generic group and a considerable number sought to engage in macro practice, reflecting a commitment to the profession's dual focus. The majority of the students within the remaining country cohorts preferred micro practice and were far less willing to adopt macro level practices.  相似文献   
146.
本文通过对远程学习者自主学习的现状分析,提出相应的策略以帮助学员更有效地开展和提高远程自主学习。  相似文献   
147.
新世纪以来,山药蛋派的研究整体而言,不是学术界的热点话题,但仍有一些有价值的学术成果出现。在流派研究方面,苏春生、席杨、傅书华、张恒等或对流派作全方位的评述,或提出卓有见地的观点。作家研究方面除赵树理外则更为贫乏,但段崇轩的马烽研究值得注意。着眼于将来,山药蛋派研究仍然有颇多言说空间。  相似文献   
148.
延安学习运动建立了一套较为完整的学习内容体系,创建了行之有效的学习方法,建构了科学有效的学习机制,不仅提高了延安时期的革命干部之学习水平与能力,并为革命与战争取得胜利提供重要的智力支持,而且为今天的学习型政党建设创建可行的有益模式,因此,延安学习运动是中国共产党不断开展自身建设的重要拐点,具有重要的开拓与启迪之功效.  相似文献   
149.
Abstract

The literature on selection has been dominated in recent decades by the ‘prediction’ paradigm. Such an approach requires a substantial number of positions to be filled in order to compute validity coefficients. There are other approaches, using a different paradigm, when concentrated on adjusting the organization and the employee. Here careful analysis of job demands is essential. This article describes such an analysis, taking the medical consultant as an example. The method can be used in an iterative way. It is useful when one has to work with small numbers of positions.  相似文献   
150.
Four methods of approximating confidence limits for the single negative binomial parameter, P, are outlined and an empirical study is presented. Some remarks on prediction intervals are also included.  相似文献   
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