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1.
This paper presents a genetic algorithm (GA) for parallel redundancy optimization in series-parallel power systems exhibiting multi-state behavior, optimizing the reliability subject to constraints. The components are binary and chosen from a list of products available in the market, and are being characterized by their feeding capacity, reliability, cost and weight. System reliability is defined as the ability to satisfy consumer demand and is presented as a piecewise cumulative load curve. In GA, to handle infeasible solutions penalty strategies are used. Penalty technique keep a certain amount of infeasible solutions in each generation so as to enforce genetic search towards an optimal solution from sides of, both, feasible and infeasible regions. We here present a dynamic adaptive penalty function which helps the algorithm to search efficiently for optimal/near optimal solution. To evaluate system reliability, a fast procedure, based on universal generating function, is used. An example considering a multi-state series-parallel power system is solved considering both homogeneous and heterogeneous types of redundancy. Also an example considering price discounts is solved. The effectiveness of the penalty function and the proposed algorithm is studied and shown graphically.  相似文献   
2.
This paper captures the experiences of the faculty members of a relatively new graduate social work program situated in the largely rural state of Haryana India in reframing the foundation year practicum through community-based and engaged action learning in small villages. Located within Bhagat Phool Singh Vishwavidyalaya (BPSMV), north India's first all women public university, the mission of which is to enhance women's engagement in the greater society through post-secondary, professional and character education, the department is educating social workers for community engagement in social development and in the development of women as an empowered group in society, particularly at the village level. Over a three-year period, the faculty has successfully launched and sustained action learning as an alternative to the traditional practicum in social work education, enhanced civic engagement among students and faculty in three rural villages, and further developed community social work as a principal focus of social work education in India. The paper offers a rationale for action learning in the graduate social work curriculum, describes and documents the department's strategy of action learning, and lays out lessons learned from action learning as a central focus of pedagogy, research, and service within BPSMV Department of Social Work and the rural villages it serves.  相似文献   
3.
When addressing infants, many adults adopt a particular type of speech, known as infant‐directed speech (IDS). IDS is characterized by exaggerated intonation, as well as reduced speech rate, shorter utterance duration, and grammatical simplification. It is commonly asserted that IDS serves in part to facilitate language learning. Although intuitively appealing, direct empirical tests of this claim are surprisingly scarce. Additionally, studies that have examined associations between IDS and language learning have measured learning within a single laboratory session rather than the type of long‐term storage of information necessary for word learning. In this study, 7‐ and 8‐month‐old infants' long‐term memory for words was assessed when words were spoken in IDS and adult‐directed speech (ADS). Word recognition over the long term was successful for words introduced in IDS, but not for those introduced in ADS, regardless of the register in which recognition stimuli were produced. Findings are discussed in the context of the influence of particular input styles on emergent word knowledge in prelexical infants.  相似文献   
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Sex selection, a gender discrimination of the worst kind, is highly prevalent across all strata of Indian society. Physicians have a crucial role in this practice and implementation of the Indian Government’s Pre-Natal Diagnostic Techniques Act in 1996 to prevent the misuse of ultrasound techniques for the purpose of prenatal sex determination. Little is known about family preferences, let alone preferences among families of physicians. We investigated the sex ratios in 946 nuclear families with 1,624 children, for which either one or both parents were physicians. The overall child sex ratio was more skewed than the national average of 914. The conditional sex ratios decreased with increasing number of previous female births, and a previous birth of a daughter in the family was associated with a 38 % reduced likelihood of a subsequent female birth. The heavily skewed sex ratios in the families of physicians are indicative of a deeply rooted social malady that could pose a critical challenge in correcting the sex ratios in India.  相似文献   
6.
ABSTRACT

Migrant women are often described as victims of the global economy: accounts of human rights abuses and economic exploitation have eclipsed more positive accounts of the impact of migrant work on women's lives. Some migrant women are positioned to make use of new opportunities which they see as empowering, in contrast to earlier experiences in their homes or sending countries. This study, based on qualitative interviews with 13 young Nepalese women working in manufacturing and agricultural sectors with Employment Permits in South Korea, highlights a rather positive window of women's empowerment. It shares the perspectives of young, mostly single women who gain self-confidence through their new ability to take care of their family (some becoming primary breadwinners). The women are also able to plan for their economic futures, and report their voices being heard more in important family decision-making. These material, relational, and perceptual improvements are all important dimensions of empowerment. In these experiences, gender intersects with age and other factors to produce a nuanced view of specific young women's experience of migrant work.  相似文献   
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We investigate longitudinal models having Brownian-motion covariance structure. We show that any such model can be viewed as arising from a related “timeless” classical linear model where sample sizes correspond to longitudinal observation times. This relationship is of practical impact when there are closed-form ANOVA tables for the related classical model. Such tables can be directly transformed into the analogous tables for the original longitudinal model. We in particular provide complete results for one-way fixed and random effects ANOVA on the drift parameter in Brownian motion, and illustrate its use in estimating heterogeneity in tumor growth rates.  相似文献   
9.
A ten-sector, sequential applied general equilibrium model is formulated, estimated, and stimulated for analyzing agricultural policy choices for India until year 2000. Ten groups of consumers (five of them rural), each with its own preferences and claims on output are recognized in the model, the groups distinguished by the range of their per capita household (real) consumption expenditure. The simulations compare: four policies with respect to the compulsory purchase and subsidized distribution to consumers of a limited amount of foodgrains and four foreign trade and aid scenarios. Procuring and freely distributing 100 kgs of grain per capita per year and financing the cost through additional taxation improves income distribution with no reduction in growth. On the other hand, the same distributional policy financed by reducing investment has a negative impact on growth.  相似文献   
10.
Decisional guidance is defined as how a decision support system (DSS) influences its users as they structure and execute the decision‐making process. It is assumed that decisional guidance has profound effects on decision making, but these effects are understudied and empirically unproven. This paper describes an empirical, laboratory‐experiment‐based evaluation of the effectiveness of deliberate decisional guidance and its four types. We developed and used a comprehensive model consisting of four evaluation criteria: decision quality, user satisfaction, user learning, and decision‐making efficiency. On these criteria, we compared decisional guidance versus no guidance, informative versus suggestive decisional guidance, and predefined versus dynamic decisional guidance. We found that deliberate decisional guidance was more effective on all four criteria; suggestive guidance was more effective in improving decision quality and user satisfaction, and informative guidance was more effective in user learning about the problem domain, whereas dynamic guidance was more effective than predefined guidance in improving decision quality and user learning; and both suggestive guidance and dynamic guidance reduced the decision time.  相似文献   
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