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71.
The time spent in dependence and the type of care an elderly receives are the two main cost drivers of long-term care (LTC). We aim to provide a better understanding of the duration of care by using a comprehensive social insurance dataset covering the LTC needs in Switzerland over a 20-years-period and including 230 000 observations on dependent elderly. First, using the framework of survival analysis, we calculate Kaplan–Meier estimates for the care duration and derive the main explaining factors through econometric models when care is received at home and in an institution. Retaining only significant covariates, the final accelerated failure time models allow us to predict the duration for different profiles of elderly along their age, gender, region of residence, type of household composition, acuity level and pre-retirement income. Second, we study the interaction of care durations when care is provided at home and in an institution. While our data supports that for short at-home care durations the time spent in institutional care is reduced, we find that both types of care are non-substitutes when the time spent at home has been longer. Under the latter regime, the time spent in institutional care remains at a constant level. Finally, given the longevity improvements over the period of observation, we analyze the impact of living longer on the time spent in dependence. Our results show that while the mean age at entry in dependence grows, the overall care duration does not significantly change. Given the expected increasing number of elderly in most developed countries, our study is relevant for government planning, budgeting social insurance schemes, estimating personal savings needs and calculating private insurance premiums.  相似文献   
72.
1.ExtendedEntropyModelEntropymodelsarewidelyusedasaforecastingtechniqueinregionalplanning,see11]and[7].Theydescribeinacertainwaythemostprobablespatialinteractionandcanbeusedtoestimateorigin-destinationtripmatrices.Butthemodelsaretoosimple,soitisdifficulttomeetpracticalrequirements.HallefjordandJo..stenl2]putforwardthegeneralizationofthestandardentropymodels.Onthebasisofthisandaccordingtothedemandofthepredictionofthetripamountfortransportationplanning,wearriveatthefollowing:wherep,μandnarepo…  相似文献   
73.
In this paper we generalize the Kalman-Yakubovic lemma to infinite dimensions—or, more precisely, to semigroups of operators over a Hilbert space. The proof differs substantially from the finite-dimensional version and is based on the Paley-Wiener-Helson-Lowdenslager factorization theorem.  相似文献   
74.
Operational researchers and social scientists often make significant claims for the value of systemic problem structuring and other participative methods. However, when they present evidence to support these claims, it is usually based on single case studies of intervention. There have been very few attempts at evaluating across methods and across interventions undertaken by different people. This is because, in any local intervention, contextual factors, the skills of the researcher and the purposes being pursued by stakeholders affect the perceived success or failure of a method. The use of standard criteria for comparing methods is therefore made problematic by the need to consider what is unique in each intervention. So, is it possible to develop a single evaluation approach that can support both locally meaningful evaluations and longer-term comparisons between methods? This paper outlines a methodological framework for the evaluation of systemic problem structuring methods that seeks to do just this.  相似文献   
75.
基于遗传算法的二层线性规划问题的求解算法   总被引:2,自引:1,他引:2  
本研究了下层以最优解返回上层的二层线性规划问题的遗传算法。在提出可行度概念的基础上,构造了二层线性规划上层规划问题的适应度函数,由此设计了求解二层线性规划问题遗传算法。为了提高遗传算法处理约束的能力,在产生初始种群时将随机产生的初始种群变为满足约束的初始种群,从而避免了使用罚函数处理约束带来的困难,最后用实例验证了本提出的二层线性规划的遗传算法的有效性。  相似文献   
76.
基于遗传算法的项目经理评价   总被引:1,自引:0,他引:1  
本文根据自然进化规则,把项目经理视为评价系统,项目经理所要满足的要求视为系统环境,用遗传算法的方法评价项目经理,力求提出一种比较客观科学的、且可以定量分析的项目经理的评价方法。  相似文献   
77.
This work presents an optimization model to support decisions in the aggregate production planning of sugar and ethanol milling companies. The mixed integer programming formulation proposed is based on industrial process selection and production lot-sizing models. The aim is to help the decision makers in selecting the industrial processes used to produce sugar, ethanol and molasses, as well as in determining the quantities of sugarcane crushed, the selection of sugarcane suppliers and sugarcane transport suppliers, and the final product inventory strategy. The planning horizon is the whole sugarcane harvesting season and decisions are taken on a discrete fraction of time. A case study was developed in a Brazilian mill and the results highlight the applicability of the proposed approach.  相似文献   
78.
The long-term planning of electricity generation in a liberalised market using the Bloom and Gallant model can be posed as a quadratic programming (QP) problem with an exponential number of linear inequality constraints called load-matching constraints (LMCs) and several other linear non-LMCs. Direct solution methods are inefficient at handling such problems and a heuristic procedure has been devised to generate only those LMCs that are likely to be active at the optimiser. The problem is then solved as a finite succession of QP problems with an increasing, though still limited, number of LMCs, which can be solved efficiently using a direct method, as would be the case with a QP interior-point algorithm. Warm starting between successive QP solutions helps then in reducing the number of iterations necessary to reach the optimiser.  相似文献   
79.
车辆路径问题的混合优化算法   总被引:11,自引:1,他引:11  
讨论了一类车辆路径调度问题(VRP)及其数学模型,并且分析了以遗传算法求解该类问题时的染色体表示和有关遗传操作,然后结合2-opt局部优化算法提出了GA with2-opt算法来求解VRP问题,试验结果说明了该算法的有效性和可行性。  相似文献   
80.
数学概念与数学实验   总被引:1,自引:1,他引:1  
华天瑞 《大学数学》2004,20(2):24-25
讨论了通过讲透基本概念、引入数学实验、适当削减运算方法的讲授来改革高职、高专的高等数学课程.  相似文献   
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