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1.
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   
2.
We investigate the impacts of complex sampling on point and standard error estimates in latent growth curve modelling of survey data. Methodological issues are illustrated with empirical evidence from the analysis of longitudinal data on life satisfaction trajectories using data from the British Household Panel Survey, a national representative survey in Great Britain. A multi-process second-order latent growth curve model with conditional linear growth is used to study variation in the two perceived life satisfaction latent factors considered. The benefits of accounting for the complex survey design are considered, including obtaining unbiased both point and standard error estimates, and therefore correctly specified confidence intervals and statistical tests. We conclude that, even for the rather elaborated longitudinal data models that were considered, estimation procedures are affected by variance-inflating impacts of complex sampling.  相似文献   
3.
Despite recent successes, Brazilian income (cash) transfer policies remain controversial, and alternative approaches to income redistribution are being actively considered. This article contributes to this debate, analysing the effects of several alternative policies for income redistribution in the Brazilian economy using a computable general equilibrium model. Simulations were conducted consistent with the following policies: direct transfer of income, reduction of taxes, and incentives to agricultural exports. The results suggest that transfer of income is the most effective in promoting redistribution of income, with a positive impact on the level of welfare of the poorest households.  相似文献   
4.
利用江汉平原农户调查数据,运用二元选择模型分析不同类型农户土壤保护认知与行为决策。结果表明:不同类型农户的土壤保护认知水平存在差异,且农户的土壤保护认知与其行为决策之间的差距较为明显;户主教育程度、农户土壤保护认知与耕地块数是影响所有类型农户土壤保护行为决策的显著因素;是否租入土地与接受农业技术培训对纯农户土壤保护行为有显著影响;人均耕地面积对I兼农户有显著影响;户主是否兼业与家庭非农就业比例对II兼农户有显著影响;户主年龄对III兼农户有显著影响。由此提出建议:提高各类农户土壤保护认知,缩小农户行为决策与认知差距的关键在于加强土壤保护知识与技术的宣传,培养农户土壤保护意识与技能,并通过土地整理等措施为农户采取土壤保护行为提供便利条件,在保障各方收入来源的基础上,引导土地从III兼农户向专业经营户流转。  相似文献   
5.
The two well-known and widely used multinomial selection procedures Bechhofor, Elmaghraby, and Morse (BEM) and all vector comparison (AVC) are critically compared in applications related to simulation optimization problems.

Two configurations of population probability distributions in which the best system has the greatest probability p i of yielding the largest value of the performance measure and has or does not have the largest expected performance measure were studied.

The numbers achieved by our simulations clearly show that none of the studied procedures outperform the other in all situations. The user must take into consideration the complexity of the simulations and the performance measure probability distribution properties when deciding which procedure to employ.

An important discovery was that the AVC does not work in populations in which the best system has the greatest probability p i of yielding the largest value of the performance measure but does not have the largest expected performance measure.  相似文献   
6.
Abstract

In this installment of “Conversations,” Dominic Boyer, Cymene Howe, and Marcel LaFlamme, of the Cultural Anthropology editorial team, discuss the ins and outs of publishing a gold open access journal in the field of anthropology. Highlights of the discussion include Cultural Anthropology’s move to open access, the ethics of open access, the growth of international readership, ongoing publishing challenges in open access, and the role libraries can play with open access publishing.  相似文献   
7.
Background: The androgen deficiency in the aging male (ADAM) affects physical, sexual, and psychological aspects with characteristics symptoms of middle-aged men. The practice of regular physical activity and physical exercise can attenuate these symptoms. The aim of this randomized clinical trial is to propose a physical exercise protocol based on concurrent training for middle-aged men with ADAM.

Method: Randomized clinical trial with a 6-month intervention will randomly divided into two groups: experimental group (EG) and control group (CG). Four evaluations will be carried out, (1) pre-intervention; (2) in the first month of intervention; (3) in the third month of intervention; (4) post-intervention, evaluating: physical, psychological, sexual, and hormonal aspects. The intervention protocol with concurrent training will have duration of 6 months; frequency of 3 times weekly, with 60?min per session. The two-way ANOVA test will be used for the inter-group and intra-group comparisons with repeated measurements, and also Sydak’s comparison test.

Conclusion: This protocol was developed with the intent of easing the symptoms of ADAM. In addition, it is believed that the concurrent training protocol could be capable to recover hormonal, physical, psychological, and sexual aspect of middle-aged men with ADAM.  相似文献   
8.
Biological control of pests is an important branch of entomology, providing environmentally friendly forms of crop protection. Bioassays are used to find the optimal conditions for the production of parasites and strategies for application in the field. In some of these assays, proportions are measured and, often, these data have an inflated number of zeros. In this work, six models will be applied to data sets obtained from biological control assays for Diatraea saccharalis , a common pest in sugar cane production. A natural choice for modelling proportion data is the binomial model. The second model will be an overdispersed version of the binomial model, estimated by a quasi-likelihood method. This model was initially built to model overdispersion generated by individual variability in the probability of success. When interest is only in the positive proportion data, a model can be based on the truncated binomial distribution and in its overdispersed version. The last two models include the zero proportions and are based on a finite mixture model with the binomial distribution or its overdispersed version for the positive data. Here, we will present the models, discuss their estimation and compare the results.  相似文献   
9.
The underground mining activity is regarded as one of the activities that cause most accidents, deaths and illnesses in the world, highlighting the coal mines. This study examined how ergonomics principles can help improve this environment, reduce the number of accidents and occupational diseases, train and empower workers and leaders and humanize the activities of the duty cycle of an underground mine. For this, it was developed a conceptual model of safety managing and health at work for the underground mining through the incorporation of ergonomics principles in the Occupational Safety and Health Management System and OHSAS 18001 (2007). The elaboration of the model was based on analysis of the environments and stages of work in underground mines and the PDCA cycle to ensure continuous improvement.  相似文献   
10.
The work of the goldsmiths consists in the manufacture of jewelry. The piece, be it an earring, bracelet or necklace, is hand-assembled. This task requires precision, skill, kindness and patience. In this work, we make use of tools such as cuticle clippers and rounded tip, beads or precious stones and also pieces of metal. This type of activity requires a biomechanical stress of hands and wrists. In order to quantify the biomechanical stress, we performed a case study to measure the movements performed by an assembly of pieces of jewelry. As method for research, filming was done during assembly of parts to a paste, using a Nikon digital camera, for 1 (one) hour. The film was edited by Kinovea software, and the task was divided into cycles, each cycle corresponds to a complete object. In one cycle, there are four two movements of supination and pronation movements of the forearm. The cycle lasts approximately sixteen seconds, totaling 1800 cycles in eight hours. Despite the effort required of the wrists, the activity shows no complaints from the employees, but this fact does not mischaracterizes the ability of employees to acquire repetitive strain injuries and work-related musculoskeletal disorders.  相似文献   
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