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291.
The 1995 wave of the Add Health study is used to investigate the relative influence of parent gender and residence on patterns of parental involvement with adolescents. Adolescent reports (N =17,330) of shared activities, shared communication, and relationship quality with both biological parents are utilized. A multidimensional scaling analysis reveals that parent gender explains most of the variance in parent‐adolescent involvement, with residential status playing a secondary yet a fundamental role in accounting for these patterns. Resident mothers who do not live with adolescents’ biological fathers engage in the broadest range of activities with their children. Unpartnered resident fathers display patterns of parenting that are as similar to mothers as they are to other fathers. 相似文献
292.
Simon-Rusinowitz L Marks LN Loughlin DM Desmond SM Mahoney KJ Zacharias BL Squillace MR Allison AM 《Journal of aging & social policy》2002,14(3-4):95-118
An increasing number of aging community providers and consumers support consumer-direction (CD) in long-term care services. In regard to devolution, consumer-direction goes beyond the usual approach of shifting responsibilities from the federal government to state governments to bring programs "closer to the people." Consumer-direction goes even further by placing resources directly in the hands of consumers. Yet, many questions remain unanswered regarding how to implement CD personal assistance services in general, and especially for older persons. This article describes the importance of examining views from multiple key stakeholders involved in implementing CD programs. We report on three background studies that have informed the Cash and Counseling Demonstration and Evaluation (CCDE) design and implementation-policy expert interviews as well as surveys and focus groups with consumers and representatives. As a fourth data source, we drew upon experiences in designing the CCDE and initial results from the first year of implementation. Each of the three studies on its own provided essential information for planning the CCDE. However, when we examined the studies together, and added CCDE design and implementation experiences, views expressed by the different stakeholders formed a type of multi-perspective "dialogue" that expanded our knowledge about implementing CD services. We hope this increased knowledge will help expand the availability of such services for consumers of any age who want to direct their own care. 相似文献
293.
Gorwaney N Van Arsdol MD Heer DM Schuerman LA 《International migration (Geneva, Switzerland)》1991,29(4):573-599
The authors describe the socioeconomic characteristics and fertility patterns of female immigrants from Latin America to the United States, with a focus on reasons for fertility differentials. "Using the one per cent public use sample from the 1970 and 1980 United States census, we first compare changes in socio economic characteristics from 1970 to 1980, and then examine the determinants of fertility of female immigrants to the United States, aged 16-49, from four Latin American areas or countries of birth.... The findings...suggest that there are direct effects of demographic, assimilation, and socioeconomic variables beyond those mediated by the variables in each of these sets. Further, regardless of the model, the effect of the clusters of demographic characteristics is most apparent. Age categories and marital status are the strongest indexed determinants of immigrant fertility.... The effect of education and employment is strong. Among assimilation variables, duration of residence and language ability are significant determinants of Hispanic immigrant fertility." (SUMMARY IN FRE AND SPA) 相似文献
294.
This paper considers an inventory system with non-instantaneous deteriorating item in which demand rate is a function of advertisement of an item and selling price. This paper aids the retailer in maximizing the total profit by determining optimal inventory and marketing parameters. In contrast to previous inventory models, an arbitrary holding cost rate and arbitrary deterioration rate have been incorporated to provide general framework to the model. First, a mathematical model is formulated and then some useful theoretical results have been framed to characterize the optimal solutions. The necessary and sufficient conditions for the existence and uniqueness of the optimal solutions are also derived. An algorithm is designed to find the optimum solutions of the proposed model. Numerical examples are included to illustrate the algorithmic procedure and the effects of key parameters are studied to analyze the behavior of the model. 相似文献
295.
The oil supply chain is facing new challenges due to emerging issues such as new alternative energy sources, oil sources scarcity, and price variability with high impact on demand and production and profit margins reduction. Additionally, the existence of large, complex and world wide spread businesses implies a complex system to be managed where distribution can be seen as one of the key areas that needs to be efficiently and effectively managed. Different types of distribution modes characterize the oil supply chain where the pipeline mode is one of the most complex to operate when having multiproduct characteristics. This paper addresses the planning of a generic oil derivatives transportation system characterized by a multiproduct pipeline that connects a single refinery to a storage tank farm. Two alternative mixed integer linear programming models (MILP) that aim to attain a set of planning objectives such as fulfilling costumers’ demands (which is mandatory) while minimizing the medium flow rate are developed. Additionally, final inventory levels are avoided to be excessively low. A real world scenario of a Portuguese company is used to validate and compare the two alternative MILP models developed in this paper. 相似文献
296.
Abstract In the field of stress research it is often assumed that social support as well as coping behaviour contributes to feelings of health and well-being. However, until now it has not been altogether clear whether a main-effect model or a buffer model was the more appropriate for explaining the role of these factors in response to stressful situations. In this paper, a research project is described in which both the direct and indirect effects of social support and coping were studied in the work situation of nurses. The results offer more support for a main-effect model than for a buffer or moderating-effect model, especially with regard to the coping strategies ‘active problem-solving’ and ‘palliative behaviour’. However, some moderating effects on nurses‘ reactions to their work situation were found for social support and for ‘comforting cognitions’ as a coping strategy. 相似文献
297.
Abstract The aim of this study was to conduct a stress audit among construction industry site managers in the UK as a precursor to a stress management intervention programme. Qualitative data were obtained from in-dept interviews with a total of 36 male middle and senior construction site managers; and aquantitative data were obtained by questionnaire. Based on the analysis of 561 postal quenstionnaires, eight stressor factors were identified, most significantly, ambiguity (i.e. role and task). Job satisfaction levels were low compared to a normative population and influenced by grade level. Measures of mental health were similar to the norm for males, but both grade of management and type of contract affected mental health. Anxiety levels were signficantly high, independent of managerial grade. The stress of work overload and role insecurity (fear of failure) were associated with reduced mental health and high anxiety, and the stress of the organizational culture and climate was the strongest predictor of job dissatisfaction. There was some cause for concern for the vulnerable high-risk groups, i.e. the extreme type A and those working overtime. Medical data from a small subset of managers (n = 78) revealed that this group evidenced a better quality of psychological health than the group in total; but a high percentage of personnel had high levels of triglycerides and cholesterol. Recommendations for action focused on the needs of specific subgroups, and guided the organization on the acceptability of possible interventions at individual, interpersonal and organizational levels. 相似文献
298.
There are production situations where a production facility (e.g. a machine) is used intermittently to produce lot sizes of certain products. Upon completion of production run, the facility may not be available for a random amount of time due to several reasons, such as: the facility needs to be maintained and the maintenance time is random due to unforeseen circumstances; or that the facility is leased by different manufacturers and the demand for the facility is random. As a result of machine unavailability, stock-out situations might arise. This paper extends the work of Abboud et al . (2000, Computers and Operations Research , 27 , 335-351) by assuming learning and forgetting in production. A new mathematical model is developed with numerical examples and sensitivity analysis provided. Furthermore, this paper determines how the overall inventory cost is influenced by the nature of the random variable that represents the unavailability time of the production facility. 相似文献
299.
This paper identifies which benchmarking databases are available for small- to medium-sized enterprises and the best way to conduct a benchmarking project given the limiting factors which exist at the present time. First, the meaning of benchmarking and performance measures, and their importance to an enterprise are explained. Second, frameworks for the identification of critical performance measures are considered. Third, different types of industrial benchmarking are identified and defined. Fourth, publicly accessible databases are critically reviewed against the requirements of industrial benchmarking. Fifth, the results of the critical review are presented in tabular form. Sixth, conclusions are drawn as how best to proceed with a benchmarking project at the present time. Seventh, recommendations for how best to address the issues raised by the critical review are presented. 相似文献
300.
This paper aims to explore the purchasing function on behalf of the provider, when the purchasing takes the form of a request for proposals (RfP) from the client. A methodology for handling the bidding process is presented, illustrated by a case study from the IT sector. The proposed methodology places risk as a factor for the selection of the best and final offer of the provider in addition to the traditional decision factors: delivery time, product cost and performance. The method is supported by a structured corporate memory and a decision support system based on the analytical hierarchy process. 相似文献