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71.
72.
The end of displacement is a main goal of international peacebuilding strategies, with increasing financial and human resources committed to it. Nevertheless, protracted internal displacement remains unabated, necessitating a review of the responses provided thus far. Durable solutions to internal displacement require a safe, permanent and secure place to settle, which puts security of tenure at the centre of any sustainable option. This article emphasizes the limited understanding of the factors that contribute to secure tenure as one of the main flaws in a predominantly legal approach to the right to restitution and the right to adequate housing in responses to internal displacement. It calls for the design of contextualized and inclusive strategies to align the de jure, de facto and perception dimensions of tenure security to support the sustainable settlement of internally displaced persons as well as the construction of peace.  相似文献   
73.
Homelessness among older people in Canada is both a growing concern, and an emerging field of study. This article reports thematic results of qualitative interviews with 40 people aged 46 to 75, carried out as part of a mixed-methods study of older people who are homeless in Montreal, Quebec, Canada. Our participants included people with histories of homelessness (= 14) and persons new to homelessness in later life (= 26). Interviews focused on experiences at the intersections of aging and homelessness including social relationships, the challenges of living on the streets and in shelters in later life, and the future. This article outlines the 5 main themes that capture the experience of homelessness for our participants: age exacerbates worries; exclusion and isolation; managing significant challenges; shifting needs and realities; and resilience, strength, and hope. Together, these findings underscore the need for specific programs geared to the unique needs of older people who are homeless.  相似文献   
74.
We propose a new procedure for the multinomial selection problem to solve a real problem of any modern Air Force: the elaboration of better air-to-air tactics for Beyond Visual Range air-to-air combat that maximize its aircraft survival probability H(θ, ω), as well as enemy aircraft downing probability G(θ, ω). In this study, using a low-resolution simulator with generic parameters for the aircraft and missiles, we could increase an average success rate of 16.69% and 16.23% for H(θ, ω) and G(θ, ω), respectively, to an average success rate of 76.85% and 79.30%. We can assure with low probability of being wrong that the selected tactic has greater probability of yielding greater success rates in both H(θ, ω) and G(θ, ω) than any simulated tactic.  相似文献   
75.
The study of deprivation, as a social indicator, is basic in the design and development of public policies because it allows decision makers to identify and analyse needy areas in order to improve their citizens’ well-being. The methodological approach proposed for the development of a new deprivation index is based on the Causal Theory whose conceptual model is analysed using Structural Equations. The domains selected for the deprivation index are: education, employment, income, housing, infrastructures and health. A structural equation model based on variance is the exploratory method used to obtain the indices pertaining to the above mentioned areas; the results obtained are seen to be quite reliable. There is a positive connection between the areas of education, employment and income while the relations between infrastructures and health are found to be negative. The results can be projected at a local level and show basic territorial deficiencies. The spatial units studied are the Andalusian (south of Spain) municipalities (770). The spatial projection of the indices obtained for the domains of deprivation highlights the existence of geographical areas which could be a potential target for public action.  相似文献   
76.
This study aimed to analyze the effects of caloric restriction on aged femoral articular cartilage of Wistar rats. Three groups of eight animals each were considered: young (YC) and old (OC) control groups fed with a normal diet and old caloric restriction group (OCR) composed of 18-month-old animals fed with a 31% less caloric diet from 6-months of age. Articular cartilage was studied through morphometry and immunohistochemistry. Body mass was 12% less in the OCR group than in the OC group. The articular cartilage from OC rats show thinner medial condyles, fewer chondrocytes, smaller chondrocytes nuclear volume and, in both condyles, a predominance of collagen type II and less collagen density compared to both YC and OCR groups (p?p?相似文献   
77.
The main purpose of dose‐escalation trials is to identify the dose(s) that is/are safe and efficacious for further investigations in later studies. In this paper, we introduce dose‐escalation designs that incorporate both the dose‐limiting events and dose‐limiting toxicities (DLTs) and indicative responses of efficacy into the procedure. A flexible nonparametric model is used for modelling the continuous efficacy responses while a logistic model is used for the binary DLTs. Escalation decisions are based on the combination of the probabilities of DLTs and expected efficacy through a gain function. On the basis of this setup, we then introduce 2 types of Bayesian adaptive dose‐escalation strategies. The first type of procedures, called “single objective,” aims to identify and recommend a single dose, either the maximum tolerated dose, the highest dose that is considered as safe, or the optimal dose, a safe dose that gives optimum benefit risk. The second type, called “dual objective,” aims to jointly estimate both the maximum tolerated dose and the optimal dose accurately. The recommended doses obtained under these dose‐escalation procedures provide information about the safety and efficacy profile of the novel drug to facilitate later studies. We evaluate different strategies via simulations based on an example constructed from a real trial on patients with type 2 diabetes, and the use of stopping rules is assessed. We find that the nonparametric model estimates the efficacy responses well for different underlying true shapes. The dual‐objective designs give better results in terms of identifying the 2 real target doses compared to the single‐objective designs.  相似文献   
78.
79.
Aalen's nonparametric additive model in which the regression coefficients are assumed to be unspecified functions of time is a flexible alternative to Cox's proportional hazards model when the proportionality assumption is in doubt. In this paper, we incorporate a general linear hypothesis into the estimation of the time‐varying regression coefficients. We combine unrestricted least squares estimators and estimators that are restricted by the linear hypothesis and produce James‐Stein‐type shrinkage estimators of the regression coefficients. We develop the asymptotic joint distribution of such restricted and unrestricted estimators and use this to study the relative performance of the proposed estimators via their integrated asymptotic distributional risks. We conduct Monte Carlo simulations to examine the relative performance of the estimators in terms of their integrated mean square errors. We also compare the performance of the proposed estimators with a recently devised LASSO estimator as well as with ridge‐type estimators both via simulations and data on the survival of primary billiary cirhosis patients.  相似文献   
80.
This article deals with a stochastic optimal control problem for a class of buffered multi-parts flow-shops manufacturing system. The involved machines are subject to random breakdowns and repairs. The flow-shop under consideration is not completely flexible and hence requires setup time and cost in order to switch the production from a part type to another, this changeover is carried on the whole line. Our objective is to find the production plan and the sequence of setups that minimise the cost function, which penalises inventories/backlogs and setups. A continuous dynamic programming formulation of the problem is presented. Then, a numerical scheme is adopted to solve the obtained optimality conditions equations for a two buffered serial machines two parts case. A complete heuristic policy, based on the numerical observations which describe the optimal policies in system states, is developed. It will be shown that the obtained policy is a combination of a KANBAN/CONWIP and a modified hedging corridor policy. Moreover, based on our observations and existent research studies extension to cover more complex flow-shops is henceforth possible. The robustness of such a policy is illustrated through sensitivity analysis.  相似文献   
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