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931.
The design of double acceptance sampling (AS) plans for attributes based on the operating characteristic curve paradigm is usually addressed by enumeration algorithms. These AS plans may be non optimal regarding the sample size to inspect as they were obtained without the requirement that the constraints at the OC curve controlled points are not violated for minimum Average Sample Number (ASN) scenarios. An approach based on mathematical programming is proposed to systematically design double AS plans for attributes, where the characteristics controlled are modelled by binomial or Poisson distributions. Specifically, Mixed Integer Nonlinear Programming (MINLP) formulations are developed and combined with an enumeration algorithm that allows finding ASN minimax optimal plans. A theoretical result is developed with the purpose of assuring the global optimum design is reached by iteration where a convenient solver is used to find local optima. To validate the algorithm, we compare our results with those of tables commonly used for practical purposes, consider different rates of risk, and setups commonly used in Lot Quality Assurance Plans (LQAS) for health monitoring programmes. Finally, we compare AS plans determined for processes described by binomial and Poisson distributions.  相似文献   
932.
In this paper considering an appropriate transformation on the Lindley distribution, we propose the unit-Lindley distribution and investigate some of its statistical properties. An important fact associated with this new distribution is that it is possible to obtain the analytical expression for bias correction of the maximum likelihood estimator. Moreover, it belongs to the exponential family. This distribution allows us to incorporate covariates directly in the mean and consequently to quantify their influences on the average of the response variable. Finally, a practical application is presented to show that our model fits much better than the Beta regression.  相似文献   
933.
A previously known result in the econometrics literature is that when covariates of an underlying data generating process are jointly normally distributed, estimates from a nonlinear model that is misspecified as linear can be interpreted as average marginal effects. This has been shown for models with exogenous covariates and separability between covariates and errors. In this paper, we extend this identification result to a variety of more general cases, in particular for combinations of separable and nonseparable models under both exogeneity and endogeneity. So long as the underlying model belongs to one of these large classes of data generating processes, our results show that nothing else must be known about the true DGP—beyond normality of observable data, a testable assumption—in order for linear estimators to be interpretable as average marginal effects. We use simulation to explore the performance of these estimators using a misspecified linear model and show they perform well when the data are normal but can perform poorly when this is not the case.  相似文献   
934.
第71届世界卫生大会通过的《增进获得辅助技术决议》对推动全球辅助技术发展具有积极意义。本文简述了《决议》出台的过程和核心内容,从政策、服务网络、产品供给、服务队伍、国际交流等维度分析落实决议的可行性,并从开展宣传、信息采集、完善政策、资源整合、国际交流等方面就落实决议、提升我国辅助技术服务水平的路径进行了探讨。  相似文献   
935.
Self-efficacy beliefs are central to mental health. Because adolescents' neighborhoods shape opportunities for experiences of control, predictability, and safety, we propose that neighborhood conditions are associated with adolescents' self-efficacy and, in turn, their internalizing problems (i.e., depression/anxiety symptoms). We tested these hypotheses using three waves of data from the Project on Human Development in Chicago Neighborhoods (N = 2,345). Results indicate that adolescents living in violent neighborhoods tended to report lower self-efficacy beliefs, partly because they were more likely to experience fear in their neighborhood. However, moving out of Chicago neighborhoods marked by violence and low collective efficacy to neighborhoods outside of the city was associated with adolescents' increased self-efficacy (vs. staying in such neighborhoods), an association explained by adolescents' school-related experiences. Finally, through self-efficacy, these neighborhood processes had an indirect association with adolescents' internalizing problems. Results partially support a model linking neighborhood conditions, cognitions about the self, and emotions.  相似文献   
936.
制约我校高水平运动队可持续发展的主要因素与对策   总被引:3,自引:3,他引:0  
运用文献资料法和逻辑分析法等分析了制约我校高水平运动队可持续发展的主要因素,提出了实现我校高水平运动队可持续发展的具体对策.  相似文献   
937.
文章根据明代以来的书志著录、19世纪末叶至今的相关研究以及个人的寻索访求,梳理出海内外<西番译语>几种主要传本的共性和特色,考察了其藏存的相关线索,同时对其珍贵的语料、史料价值作了简评.  相似文献   
938.
The historic cities of Brazil, despite its colonial structure, don't fail to go through transformations that affect contemporary cities, which is the main source of problems, leading to new approaches to urban issues such as mobility and accessibility. The uncontrolled growth of tourism in the historic cities can be considered as a big problem, because at the same time, they have committed to the conservation of its built heritage and demand control of the activities that occur in their areas without harm. Then, a permanent dialogue between conservatives and planners could be accomplished by joining the various sectoral policies. The study of urban mobility in historical sites was in fact the focus of this work because of their peculiarities, such as its specific characteristics of urban structure, morphology and occupation. In fact, the development of tourism in historic centers generates specific demands, such as adaptation to new uses of the houses, intensive movement of people and vehicles, illegal parking, among others. Beyond threatening the city preservation, does not provide mobility and accessibility to tourists, because these cities were not designed for the tourism conditions and needs of contemporary life. Characteristic features of Brazilian baroque cities, such as topography , the narrow streets, narrow or nonexistent sidewalks, steep turns and ramps strong, are not suitable for heavy vehicles, traffic and pedestrian circulation. Thus, studies concerning conservation urban integrated are aimed at an approach to interaction between historic preservation of the environment with the dynamic socio-economic of the local.  相似文献   
939.
In the workplace there are risk factors that can overwhelm the health of the worker causing physical and psychological disorders. Among these disorders, is occupational stress. Thus, this research proposes to measure the mental workload of job stress from the identification of demand, control and social support. It is an observational cross-sectional epidemiological character, performed with the Rectory office workers at the State University of West Paraná (Unioeste). Data collection was due to the application of the "Job Stress Scale" (JSS) and in its reduced version adapted to Portuguese. The survey sample consisted of 44 individuals. Statistical analysis was correlated inversely with medium intensity (r = -0.404) between age and social support. For males was found between control and age (r = 0.603). According to the data obtained, we conclude that most workers are exposed to passive work, leading to loss of skills or disinterest in the job. This study highlights the importance of research in the area and the need for new actions that change the conditions of stress at work.  相似文献   
940.
The generation growing and diversified of Municipal Solid Waste is configured as an environmental problem, economic and social deterioration, especially, by application of inappropriate management of them. Faced with this urban context, the research in development presents as specific objective assessment of the quality of life of the gatherers of recyclable materials were active in the city of Juiz de Fora, in the brazilian state of Minas Gerais. In addition, the objective is, still, the recognition of the activity of sorting performed by "scavengers" in order to maximize the reduction, reuse and recycling energy and material waste daily. The proposed methodology is based on the application of the questionnaire Word Health Organization Quality of Life (WHOQOL-100), prepared by the World Health Organization, in order to value the quality of life of the gatherers of recyclable materials, involved, even in educational workshops in order to discuss and organize strategies of health care and scouting to the basement to public policies.  相似文献   
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