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91.
This paper examines the evidence base for interventions which seek to enhance social support resources for families with children at risk of adverse developmental outcomes. Substantive and methodological issues related to the implementation of social support interventions are discussed and a research agenda for the development, testing and evaluation of such interventions is presented.  相似文献   
92.
Lesbian, gay, bisexual, transgender and queer-identified (LGBTQ) youth are a population with a unique set of service needs. Existing research on effective service methods with LGBTQ youth is limited. Youth empowerment holds potential as an approach that can impact well-being among youth who face discrimination. The current study explores the relationship between the social justice youth development framework (Ginwright and James, New Directions Youth Dev 96:27–46, 2002) and youth empowerment in a sample of LGBTQ youth. Multiple regression analysis of data collected through a community-based youth program identified critical consciousness and community engagement as significant predictors of empowerment. Findings suggest that programs that promote these factors among LGBTQ youth using the social justice youth development framework may enhance empowerment thereby increasing other aspects of well-being.  相似文献   
93.
This article uses privileged families who hire Independent Educational Consultants (IECs) as an instance to examine how privileged parents collaborate with individuals whom they consider educational experts to support their children in the college race. We argue that advantaged parents' anxieties about their children have created a market for IECs who provide expert advice in order to mitigate the uncertainties that these parents experience and to manage various goals that they want to achieve at an important turning point in their children's lives. Drawing primarily on interviews with parents who work with IECs, we introduce the concept of “collaborative cultivation” to analyze the processes whereby advantaged parents rely on the expertise and expert status of private counselors to cope with their and their children's vulnerability in the college race while at the same time preparing their children for the unknown future. The parental method of “concerted cultivation” reveals how elite parents rely on individuals they perceive as experts to establish “bridges” between their own social worlds and the academic worlds that appear to beyond their control. This bridging labor points to the myriad cultural beliefs enacted to justify the child‐rearing goals that privileged parents wish to accomplish by working with IECs.  相似文献   
94.
95.
The crucial issues in the administration of higher education embody the very purpose, function, and concept of each institution. The institution's administrative policies are based on the combined philosophy of many conflicting interest groups such as taxpayers, donors, administrators, faculty, students, staff, and users of university services. A function performed by the university which is receiving increasing attention and outside pressure is the formulation of admissions policy for newly entering students. This paper investigates problems involved in the admissions planning and presents a goal programming model as an optimization tool for the problem.  相似文献   
96.
The purpose of this paper is to present the theory of the multi-product firm in situations where the revenue function depends not only on the rate of output but also on changes in the rate of output, and, similarly, where the cost function depends on changes in the rate of factor utilization as well as the rate of their utilization. Since the analysis will utilize the calculus of variations, a general introduction to this technique is also presented. The model analyzed assumes perfect foresight and knowledge concerning the revenue, cost, and production functions, and the calculus of variations is used to derive the conditions for an extremum. The first section presents the mathematical model and the model of the firm, and the optimality conditions are discussed in the second section.  相似文献   
97.
本文通过解读准噶尔汗国灭亡后卫拉特蒙古佚名氏史家撰写的几篇托忒文史籍,探讨当时卫拉特人对汗国灭亡的反思及对清准战争的历史记忆.几位史家的文本反映了"四卫拉特"这一历史框架的稳定性,以及卫拉特人在政治认同方面的一些变化.  相似文献   
98.
A heteroscedastic regression based on the odd log-logistic Marshall–Olkin normal (OLLMON) distribution is defined by extending previous models. Some structural properties of this distribution are presented. The estimation of the parameters is addressed by maximum likelihood. For different parameter settings, sample sizes and some scenarios, various simulations investigate the performance of the heteroscedastic OLLMON regression. We use residual analysis to detect influential observations and to check the model assumptions. The new regression explains the mass loss of different wood species in civil construction in Brazil.  相似文献   
99.
In the production planning and control of discrete-parts manufacture, aggregation of parts into families, on the basis of similarity, is carried out to ease both long-horizon planning and short-horizon scheduling. Additional advantages are related to those of group technology (GT), such as simplifying the flow of parts and tools and reducing both set-up and production costs. The problem of formally forming part families is presented and discussed. Previous work is reviewed and assessed. Two solution approaches, one based on a location model, the other on simulated annealing, are presented and compared along with test results. The location formulation, which results in an integer programming model solved by Lagrangian relaxation, proved capable of producing solutions of excellent quality, but only for relatively small problem instances. In contrast, simulated annealing, which is a general heuristic approach to combinatorial optimization, produced solutions of comparable quality and could handle realistically large problem instances. However, careful design of the simulated annealing algorithm is crucially important. An effective design is presented.  相似文献   
100.
In this article, we first propose the modified Hannan–Rissanen Method for estimating the parameters of autoregressive moving average (ARMA) process with symmetric stable noise and symmetric stable generalized autoregressive conditional heteroskedastic (GARCH) noise. Next, we propose the modified empirical characteristic function method for the estimation of GARCH parameters with symmetric stable noise. Further, we show the efficiency, accuracy and simplicity of our methods with Monte-Carlo simulation. Finally, we apply our proposed methods to model the financial data.  相似文献   
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