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531.
This paper reviews the professional literature with respect to the social work profession's involvement in end-of-life care. The search process was conducted by entering key words in various combinations to electronic databases. Eligible articles were required to address one of the following: roles and activities of social workers in providing end-of-life care; core principles valued by social workers in the provision of end-of-life care; and barriers to provision of effective end-of-life care. The literature from 1990 through July 2004 was searched most rigorously. Based on this review, suggestions for where the profession of social work should focus its energies are offered. These key areas include focusing on generating empirically-based knowledge for practice and policy analysis and developing a system of social work education that addresses the unique knowledge and skills needed to participate in end-of-life practice as competent and informed professional practitioners. Current initiatives with regard to critical areas are summarized. 相似文献
532.
Chien‐Ming Chen Yeming Gong Ren B.M. De Koster Jo A.E.E. Van Nunen 《Production and Operations Management》2010,19(1):70-82
This paper develops a novel framework to evaluate the integral performance of order picking systems with different combinations of storage and order picking policies. The warehousing literature on order picking mostly considers minimizing either elapsed time or distance as the sole objective, whereas warehouse managers in a supply chain have to look beyond single‐dimensional performance and consider trade‐offs among different criteria. Thus managers still need a unified and efficient framework to select a portfolio of appropriate order picking policies from a multi‐criteria and contextual perspective. Our framework—combining data envelopment analysis, ranking and selection, and multiple comparisons—provides an efficient methodology to simultaneously analyze several interrelated problems in order picking systems with multiple performance attributes, such as service levels and operational costs. We demonstrate our approach through comprehensive evaluations of order picking policies in three low‐level, picker‐to‐parts rectangular warehouses facing demand variations. 相似文献
533.
We consider the scheduling of truck arrivals at an air cargo terminal. By coordinating arrivals of cargo delivery trucks with outbound flight departure schedules, some of the shipments can be transferred directly to the departing flights, while others will be stored at the terminal's storage facility and incur extra handling and storage costs. The objective is to obtain a feasible schedule so as to minimize the total cost of operations. We formulate the problem as a time‐indexed integer program and show that, even with limited number of unloading docks at the terminal, the problem is non‐trivial (NP‐hard in the strong sense). Our solution method includes an exact solution procedure to determine an optimal unloading sequence for the shipments carried by each truck, together with a Lagrangian relaxation‐based heuristic for assigning trucks to truck docks and determining truck arrival times. We conducted computational experiments to test the performance of our solution method. Computational results show that our method can generate near‐optimal solutions efficiently. Our simulation results indicate that the scheduling approach proposed in this paper has the potential to generate significant cost savings over a first‐come, first‐served approach currently used at the air cargo terminal that we observed. 相似文献
534.
The potential to foster successfully starts with developing and supporting competency in 12 domains: providing a safe and secure environment, providing a nurturing environment, promoting educational attainment and success, meeting physical and mental healthcare needs, promoting social and emotional development, supporting diversity and children's cultural needs, supporting permanency planning, managing ambiguity and loss for the foster child and family, growing as a foster parent, managing the demands of fostering on personal and familial well-being, supporting relationships between children and their families, and working as a team member. This article describes each domain and reviews relevant research to help guide the assessment of practicing and future foster parents. 相似文献
535.
The authors investigated vigorous physical activity, psychological well-being, and self-reported illness during transition to first-year university life in a sample of 175 Canadian undergraduates. At the completion of their first year of university study, participants completed retrospective measures assessing vigorous physical activity, upper respiratory infectious illness (URI), doctor visits, as well as measures of psychological well-being. Based on nationally recommended (US Department of Health and Human Services) standards, 61% of students reported engaging in adequate levels of vigorous activity during their first year at university. The authors found no differences in URIs between sufficiently and insufficiently active students. However, insufficiently active students scored lower on psychological well-being and were twice as likely to have consulted a physician regarding an illness compared with sufficiently active students. 相似文献
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538.
We study the incentives that drive an online firm to make various types of innovations in a competitive environment. We develop and use a simplified price competition model between two retailers, one online and one offline. A given fraction of consumers, called the Internet penetration, comparison shop online, independent of their customer type, thereby creating two markets for the offline retailer, a captive market and a competitive market. The online product has the steeper of the two linear utility functions, which means that the customers who buy online in our model are high end. We focus on the competitive region in which both retailers are (strictly) profitable in the competitive market and consider innovations that increase high‐end appeal, low‐end appeal, and/or reduce unit cost. We find that the online firm has a strong incentive to invest in innovations that either reduce unit cost and/or, equivalently, increase the appeal to all consumers equally. Investments of this type are strategic complements: implementing one increases the value of another, so the value of two innovations of this type is more than the sum of the values of each individually. We identify a relative strength measure of the online firm such that, as its high‐end appeal increases and/or its unit cost decreases, we say that the online firm is stronger. This strength measure facilitates drawing an explicit dividing line between strong and weak online firms. If Internet penetration increases, the online firm's profits increase if and only if it is strong. If penetration increases over time, it is possible for a strong firm to turn weak and see its profits decrease and possibly disappear completely. A strong online firm has more opportunity to profit from low‐end innovations than does a weak one, while the opposite is true for high‐end innovations. Interestingly, some innovations may actually decrease the online firm's profits. We discuss the implications of our results for existing and future online innovations. 相似文献
539.
Martin Pesendorfer Philipp Schmidt‐Dengler 《Econometrica : journal of the Econometric Society》2010,78(2):833-842
Recursive procedures which are based on iterating on the best response mapping have difficulties converging to all equilibria in multi‐player games. We illustrate these difficulties by revisiting the asymptotic properties of the iterative nested pseudo maximum likelihood method for estimating dynamic games introduced by Aguirregabiria and Mira (2007). An example shows that the iterative method may not be consistent. 相似文献
540.
In make‐to‐stock production systems finished goods are produced in anticipation of demand. By contrast, in stockless production systems finished goods are not produced until demand is observed. In this study we investigate the problem of designing a multi‐item manufacturing system, where there is both demand‐ and production‐related uncertainty, so that stockless operation will be optimal for all items. For the problem of interest, we focus on gaining an understanding of the effect of two design variables: (i) manufacturing speed—measured by the average manufacturing rate or, equivalently, the average unit manufacturing time, and (ii) manufacturing consistency—measured by the variation in unit manufacturing times. We establish conditions on these two variables that decision makers can use to design stockless production systems. Managerial implications of the conditions are also discussed. 相似文献