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211.
In a survey of current attitudes of parents towards child rearing, 386 parents of 4th grade children completed questionnaires containing Hereford's Parent Attitude Scale. Results indicated that parents with the highest education and occupational status were: more confident in themselves as parents; more inclined to believe that they could influence their child's behaviour; more accepting of the child as an individual; shared ideas and feelings more often with their child; and were more likely to enjoy a mutually trusting relationship with their child. This suggests that programmes aimed at improving parent-child relationships should be primarily directed towards the less well educated and those of lower occupational standing. Yet the Health Commission, in pilot Parent Effectiveness Training (PET) programmes found that parents who joined the programmes were even better educated than those in the survey, and already had very favourable attitudes towards child rearing.  相似文献   
212.
The multilinear extension of a cooperative game was introduced by Owen in 1972. In this contribution we study the Lovász extension for cooperative games by using the marginal worth vectors and the dividends. First, we prove a formula for the marginal worth vectors with respect to compatible orderings. Next, we consider the direct market generated by a game. This model of utility function, proposed by Shapley and Shubik in 1969, is the concave biconjugate extension of the game. Then we obtain the following characterization: The utility function of a market game is the Lovász extension of the game if and only if the market game is supermodular. Finally, we present some preliminary problems about the relationship between cooperative games and combinatorial optimization.  相似文献   
213.
This paper presents the results of a case study looking at the views of teachers and other educational professionals pertaining to the academic progress and general integration of immigrant schoolchildren in multicultural schools in the province of Huelva (Andalusia, Spain). It is organised into three sections: first, the geographical and social context of the study is described, focusing in particular on the impact on schools of migratory trends within the province associated with strawberry cultivation. This is followed by a presentation of the results of a field study into the educational panorama of immigrant pupils from various countries, drawing on verbal reports by teachers and school administrators. Finally, some conclusions are suggested for possible categories of analysis with a view to opening new lines of research in the future.  相似文献   
214.
To many, development and adoption of professional standards for measurement and evaluation (M&E) is one of the most promising approaches for advancing public relations practice. In recent years, there has been a surge in efforts to develop standards for M&E in different parts of the world. Prominent examples of this include standard terminologies, metrics, principles for best practice in the field, and evaluation frameworks. Regardless of their alleged importance, however, the acceptance and application of such M&E standards in the practice varies significantly. To better understand the process by which standards in this field are developed and adopted, this article draws on recent concepts from organization studies (cf. Slager, Gond, & Moon, 2012) to analyze the trajectories of four seminal standards attempts: The Barcelona Principles and the AMEC Integrated Evaluation Framework on an international level, the DPRG/ICV Framework used in German-speaking countries, and the GCS Framework in the United Kingdom. The article reveals, by way of an interpretive qualitative approach, the various strategies undertaken to a) develop common sets of terms and rules, b) engage relevant actors in the design, promotion, and implementation of proposed standards, and c) to reinforcing standards symbolically.  相似文献   
215.
Despite its social, political and economic relevance, child well-being remains a challenging construct to define and measure accurately. This holds true especially for children growing up in at-risk families, where their development is hindered by many adverse circumstances. Typically, the well-being of child welfare (CW) referred children has been conceptualized as the absence of negative outcomes, and the study of its determinants has been limited to children’s micro-systems. In this study, we aimed to obtain a suitable indicator of child well-being and to test a model of the determinants of CW referred children’s well-being including parental, family and wider contextual variables. The sample included 249 parents and 46 case managers from Portuguese and Spanish CW services. A three-domain solution from selected items of the Child Well-Being Scales (Physical, Academic and Socioemotional) was tested and confirmed through Confirmatory Factor Analysis. The results of structural equation modeling for each domain revealed that risk factors nested in the wider context and those related to material disadvantage were the most powerful predictors of physical well-being, while parenting and family functioning variables predicted better both academic and socio-emotional well-being. Our findings suggest that different risk and protective factors matter for different outcomes and that most of these factors are associated with each other. Therefore, interventions with at-risk children must take this specificity into account when targeting each domain of well-being, and efforts could be allocated to a few modifiable dimensions, which would in turn positively affect other parental and family factors.  相似文献   
216.
In December 2015, a cyber‐physical attack took place on the Ukrainian electricity distribution network. This is regarded as one of the first cyber‐physical attacks on electricity infrastructure to have led to a substantial power outage and is illustrative of the increasing vulnerability of Critical National Infrastructure to this type of malicious activity. Few data points, coupled with the rapid emergence of cyber phenomena, has held back the development of resilience analytics of cyber‐physical attacks, relative to many other threats. We propose to overcome data limitations by applying stochastic counterfactual risk analysis as part of a new vulnerability assessment framework. The method is developed in the context of the direct and indirect socioeconomic impacts of a Ukrainian‐style cyber‐physical attack taking place on the electricity distribution network serving London and its surrounding regions. A key finding is that if decision‐makers wish to mitigate major population disruptions, then they must invest resources more‐or‐less equally across all substations, to prevent the scaling of a cyber‐physical attack. However, there are some substations associated with higher economic value due to their support of other Critical National Infrastructures assets, which justifies the allocation of additional cyber security investment to reduce the chance of cascading failure. Further cyber‐physical vulnerability research must address the tradeoffs inherent in a system made up of multiple institutions with different strategic risk mitigation objectives and metrics of value, such as governments, infrastructure operators, and commercial consumers of infrastructure services.  相似文献   
217.
This paper demonstrates how it is possible to combine SMED with Centerlining in complex production environments with numerous changes of format, product, raw materials and tools. This research proposes a methodology involving an initial application of Centerlining and, once the machinery and the process are stable, the subsequent implementation of SMED. Furthermore, it aims to show that it is possible to achieve improved output and reduced machinery changeover time while ensuring that the effect achieved by SMED is more stable. This increases the organizational advantages with respect to the implementation of SMED without prior application of Centerlining. The most important overall conclusion is that a successful application of SMED must always be accompanied by another type of tool or technique to maximize the results of its application. And, as presented in this work, one technique that enables significant improvements to SMED is the application of Centerlining.  相似文献   
218.
In the field of sensitivity analysis, Sobol’ indices are sensitivity measures widely used to assess the importance of inputs of a model to its output. The estimation of these indices is often performed through Monte Carlo or quasi-Monte Carlo methods. A notable method is the replication procedure that estimates first-order indices at a reduced cost in terms of number of model evaluations. An inherent practical problem of this estimation is how to quantify the number of model evaluations needed to ensure that estimates satisfy a desired error tolerance. This article addresses this challenge by proposing a reliable error bound for first-order and total effect Sobol’ indices. Starting from the integral formula of the indices, the error bound is defined in terms of the discrete Walsh coefficients of the different integrands. We propose a sequential estimation procedure of Sobol’ indices using the error bound as a stopping criterion. The sequential procedure combines Sobol’ sequences with either Saltelli’s strategy to estimate both first-order and total effect indices, or the replication procedure to estimate only first-order indices.  相似文献   
219.
实验室科学家用于完成研究的工作时间是有限的。在如今现代化、实验仪器密集的实验室里,每年用于一位科学家和实验室场地的开销可能超过$250000或$120/h。由于完成研究的成本高,而且时间有限,因此需要考虑许多因素来最优化的利用科学家时间。这篇文章以一个实际调查为例讨论了如下因素,包括实验室工作流程,高效液相色谱(HPLC)分离中的溶剂质量以及如何避免重复性工作,如何使用简单自动化设备来监测实验状态从而除去多步骤和减少工作频率以节省科学家的时间。当将所有小细节纳入考虑范围中时,因节省细碎的时间而对实验成本的节约和实验效率的提升具有非常重要的潜在影响。  相似文献   
220.
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