931 resultados para Module drivers


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This paper is concerned with the design of a Ku-band active transmit-array module of transistor amplifiers excited by either a pyramidal horn or a patch array Optimal distances between the active transmit array and the signal-launching:receiving device, which is either a passive corporate-fed array or a horn, are determined to maximise the power gain at a design frequency: Having established these conditions, the complete structure is investigated in terms of operational bandwidth and near-field and far-field distributions measured at the output side of the transmit array, The experimental results show that the use of a corporate-fed array as an illuminating/receiving device gives higher gain and significantly larger operational bandwidth, An explanation for this behavior is sought.

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The taxi industry provides a strategic site to explore workplace deviance in low supervision, low status, occupational settings. Despite this theoretical opportunity and the objective importance of the taxi industry worldwide, very little is known about deviance among taxi drivers. Making use of interview data, this exploratory study maps out forms of workplace deviance and the explanations given for them by a sample of male taxi drivers. Major illegal activities reported included speeding, driving unsafe vehicles, taking drugs, and fraud. Theories pertaining to worker alienation, stress management, victim precipitation, and social control were relevant to the rationalizations some of the drivers provided to account for their illegal behaviors. We conclude that the occupational culture of taxi drivers and the structure of the taxi industry facilitate the forms of deviance reported here.

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This text focuses on the major drivers of Brazilian agricultural cooperation in Africa as conceived and pursued from 2004 to 2014, with emphasis on the impacts of political and economic international changes that took place in that period, and particularly the impacts of the 2008 economic crisis, in framing Brazil's foreign policy and development assistance initiatives. It addresses current international forces and developments at the systemic level, but also analyses recent economic domestic developments, in particular those directly related to Brazilian agriculture and those related to the policy framework of its evolving internationalization. Special attention is paid to the dual dimensions of Brazilian agricultural policy and to its projection in agricultural cooperation as pursed in Africa.

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Metaheuristics performance is highly dependent of the respective parameters which need to be tuned. Parameter tuning may allow a larger flexibility and robustness but requires a careful initialization. The process of defining which parameters setting should be used is not obvious. The values for parameters depend mainly on the problem, the instance to be solved, the search time available to spend in solving the problem, and the required quality of solution. This paper presents a learning module proposal for an autonomous parameterization of Metaheuristics, integrated on a Multi-Agent System for the resolution of Dynamic Scheduling problems. The proposed learning module is inspired on Autonomic Computing Self-Optimization concept, defining that systems must continuously and proactively improve their performance. For the learning implementation it is used Case-based Reasoning, which uses previous similar data to solve new cases. In the use of Case-based Reasoning it is assumed that similar cases have similar solutions. After a literature review on topics used, both AutoDynAgents system and Self-Optimization module are described. Finally, a computational study is presented where the proposed module is evaluated, obtained results are compared with previous ones, some conclusions are reached, and some future work is referred. It is expected that this proposal can be a great contribution for the self-parameterization of Metaheuristics and for the resolution of scheduling problems on dynamic environments.

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With the current increase of energy resources prices and environmental concerns intelligent load management systems are gaining more and more importance. This paper concerns a SCADA House Intelligent Management (SHIM) system that includes an optimization module using deterministic and genetic algorithm approaches. SHIM undertakes contextual load management based on the characterization of each situation. SHIM considers available generation resources, load demand, supplier/market electricity price, and consumers’ constraints and preferences. The paper focus on the recently developed learning module which is based on artificial neural networks (ANN). The learning module allows the adjustment of users’ profiles along SHIM lifetime. A case study considering a system with fourteen discrete and four variable loads managed by a SHIM system during five consecutive similar weekends is presented.

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OBJECTIVE: The increasing proportion of older adults in the general population and the specific characteristics of this age group show the need for the development of specific instruments to measure quality of life in older adults. The study aimed at describing the development and validation of the Portuguese version of the World Health Organization Quality of Life for Older Persons (WHOQOL-OLD) module. METHODS: The WHOQOL-OLD instrument was administered in a sample of 424 older adults in the city of Porto Alegre, Southern Brazil, in 2005. The questionnaire comprises 24 items divided into six facets: sensory abilities; autonomy; past, present and future activities; social participation; death and dying; and intimacy. Besides the WHOQOL-OLD module, the WHOQOL-BREF, BDI and BHS instruments were also applied. The instrument's internal consistency was assessed using Cronbach's alpha coefficient. RESULTS: The instrument showed adequate internal consistency (Cronbach's coefficients ranging from 0.71 to 0.88), discriminant validity (p<0.01), concurrent validity (correlation coefficients ranging from -0.61 to -0.50) and test-retest reliability (correlation coefficients ranging from 0.58 to 0.82). Findings concerning criterion validity need further studies. CONCLUSIONS: The WHOQOL-Old module is a useful alternative with good psychometric performance in the investigation of quality of life in older adults.

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OBJECTIVE: To evaluate the Brazilian version of WHOQOL-OLD Module and to test potential changes to the instrument to increase its psychometric adequacy. METHODS: A total of 424 older adults living in a city in Southern Brazil completed the WHOQOL-OLD instrument, in 2005. Rasch analysis was used to explore the psychometric performance of the scale, as implemented by the RUMM2020 software. Item-trait interaction, threshold disorders, presence of differential item functioning and item fit, were analyzed. RESULTS: Two ("death and dying" and "sensory abilities") out of six domains showed inadequate item-trait interactions. Rescoring the response scale and deleting the most misperforming items led to scale improvement. The evaluation of domains and items individually showed that the "intimacy" domain does perform well in contrast to the findings using the classical approach. In addition, the "sensory abilities" domain does not derive an interval measure in its current format. CONCLUSIONS: Unidimensionality and local independence were seen in all domains. Changes in the response scale and deletion of problematic items improved the scale's performance.

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OBJETIVO: Analisar as propriedades psicométricas iniciais da versão brasileira de instrumento de avaliação da qualidade de vida relacionada à saúde de crianças e adolescentes com dermatite atópica. MÉTODOS: Estudo transversal realizado com amostra de 52 crianças e adolescentes, com idades entre oito e 18 anos, diagnosticados com dermatite atópica, e seus responsáveis, recrutados em serviço de dermatologia de hospital universitário na cidade de São Paulo, SP, em 2009. Foram avaliadas a validade de construto, a confiabilidade de consistência interna e a correlação entre as respostas de crianças e adolescentes e seus responsáveis da versão brasileira do Atopic Dermatitis Module (DISABKIDS-ADM). RESULTADOS: A confiabilidade de consistência interna foi satisfatória, com coeficiente alfa de Cronbach aceitável para as dimensões constantes no instrumento (0,7024/0,8124 e 0,7239/0,8604). A análise multitraço-multimétodo para validade convergente mostrou valores maiores que 0,30 para todos os itens. Quanto à validade discriminante, a análise revelou resultados satisfatórios. A concordância entre as versões self e proxy foi avaliada pelo coeficiente de correlação intra-classe, com valores de 0,8173 para impacto e 0,7629 para estigma. CONCLUSÕES: Diante dos resultados encontrados, considera-se que o instrumento DISABKIDS-ADM pode ser utilizado por pesquisadores brasileiros depois de finalizado seu processo de validação, por seus resultados iniciais apontarem propriedades psicométricas satisfatórias, que permitem considerá-lo um instrumento válido e confiável.

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OBJECTIVE: To analyze the putative effect of type of shift and its interaction with leisure-time physical activity on cardiovascular risk factors in truck drivers.METHODS: A cross-sectional study was undertaken on 57 male truck drivers working at a transportation company, of whom 31 worked irregular shifts and 26 worked on the day-shift. Participants recorded their physical activity using the International Physical Activity Questionnaire along with measurements of blood pressure, body mass index and waist-hip ratio. Participants also provided a fasting blood sample for analysis of lipid-related outcomes. Data were analyzed using a factorial model which was covariate-controlled for age, smoking, work demand, control at work and social support.RESULTS: Most of the irregular-shift and day-shift workers worked more than 8 hours per day (67.7% and 73.1%, respectively). The mean duration of experience working the irregular schedule was 15.7 years. Day-shift workers had never engaged in irregular-shift work and had been working as a truck driver for 10.8 years on average. The irregular-shift drivers had lower work demand but less control compared to day-shift drivers (p < 0.05). Moderately-active irregular-shift workers had higher systolic and diastolic arterial pressures (143.7 and 93.2 mmHg, respectively) than moderately-active day-shift workers (116 and 73.3 mmHg, respectively) (p < 0.05) as well as higher total cholesterol concentrations (232.1 and 145 mg/dl, respectively) (p = 0.01). Irrespective of their physical activity, irregular-shift drivers had higher total cholesterol and LDL-cholesterol concentrations (211.8 and 135.7 mg/dl, respectively) than day-shift workers (161.9 and 96.7 mg/dl, respectively (ANCOVA, p < 0.05).CONCLUSIONS: Truck drivers are exposed to cardiovascular risk factors due to the characteristics of the job, such as high work demand, long working hours and time in this profession, regardless of shift type or leisure-time physical activity.

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The aim of this article was to describe the attention functioning of twenty-two truck drivers and its relationship with amphetamine use. Those drivers who reported using amphetamines in the twelve months previous to the interview had the best performance in a test evaluating sustained attention functioning. Although amphetamine use may initially seem advantageous to the drivers, it may actually impair safe driving. The findings suggest the importance of monitoring the laws regarding amphetamine use in this country.