RELAÇÕES DO EMPOWERMENT PSICOLÓGICO COM O SISTEMA DE MENSURAÇÃO DE DESEMPENHO E O DESEMPENHO GERENCIAL

Directory of Open Access Journals (Sweden)

Roberto Carlos Klann

2014-12-01

Full Text Available A relação do empowerment psicológico com aspectos organizacionais, como o desempenho no trabalho e o sistema de mensuração de desempenho, vem despertando interesse em pesquisas acadêmicas. Espera-se que as teorias psicológicas indiquem que mecanismos cognitivos e motivacionais sejam aptos a explicar a relação entre os sistemas de mensuração de desempenho e o desempenho gerencial. Assim, o objetivo deste estudo é analisar a relação entre o empowerment psicológico com o sistema de mensuração de desempenho da organização e com o desempenho gerencial dos seus empregados. Pesquisa descritiva foi realizada com dados coletados por meio de levantamento, com aplicação da técnica estatística de Partial Least Squares (PLS. Um questionário adaptado de Hall (2008, composto de quatro blocos de perguntas, foi enviado para 50 empregados de setores administrativos de quatro empresas localizadas em Santa Catarina, dos quais 20 o responderam. Os resultados indicam relações de algumas dimensões do empowerment psicológico com a compreensibilidade do sistema de mensuração de desempenho (PMS e com o desempenho gerencial, embora sejam apenas parciais. Conclui-se que o empowerment psicológico dos empregados não apresenta associação significativa com o sistema de mensuração de desempenho e com o desempenho gerencial dos empregados.

Comparação do desempenho funcional de crianças portadoras de síndrome de Down e crianças com desenvolvimento normal aos 2 e 5 anos de idade Comparison of functional performance among children with Down syndrome and children with age-appropriate development at 2 and 5 years of age

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Marisa Cotta Mancini

2003-06-01

Full Text Available OBJETIVO: Comparar o desempenho funcional de crianças portadoras de síndrome de Down (SD com crianças normais (DN, aos 2 e 5 anos de idade. MÉTODO: Quarenta crianças foram alocadas em quatro grupos (n=10: 1 crianças com SD de 2 anos; 2 crianças com SD de 5 anos; 3 crianças normais de 2 anos; 4 crianças normais de 5 anos. Todas foram avaliadas pelo teste funcional PEDI, que quantifica o desempenho infantil (habilidades e independência em três áreas: auto-cuidado, mobilidade e função social. Testes de análises de variância fatorial foram utilizados para comparar médias dos grupos e testar fatores de interação idade x patologia. Contrastes pré-planejados foram usados para identificar as comparações bivariadas significativas. RESULTADOS: Os fatores idade e patologia foram significativos nas três áreas de desempenho de habilidades e de independência. O fator de interação idade x patologia mostrou-se significativo nas habilidades de auto-cuidado e mobilidade, e na independência em mobilidade e função social. Comparações bivariadas indicaram que aos dois anos, o desempenho de crianças normais é superior nas três áreas de habilidades funcionais e de independência. Entretanto, aos 5 anos, diferenças significativas entre os grupos foram observadas nas habilidades de auto-cuidado e de função social e na independência em auto-cuidado e em função social. CONCLUSÃO: Resultados informam áreas de desempenho onde o atraso apresentado por crianças com SD manifesta-se funcionalmente, aos dois e cinco anos de idade. Dados indicam que as diferenças observadas entre os dois grupos são influenciadas pela idade, não permanecendo constante ao longo do desenvolvimento.OBJECTIVE: To compare the functional performance of Down's syndrome (DS children with normally developing children (ND, at 2 and 5 years of age. METHOD: Forty children were allocated into four groups (n=10: 1 children with DS with 2 years of age; 2 children

Efeitos crônicos do exercício resistido com contrações recíprocas no desempenho funcional e proprioceptivo de indivíduos jovens: ensaio controlado aleatório

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Euler Alves Cardoso

2014-10-01

Full Text Available http://dx.doi.org/10.5007/1980-0037.2014v16n6p618 Estudos sugerem que benefícios do exercício resistido (ER com pré-ativação da musculatura antagonista podem ser transferidos para atividades funcionais. No entanto, estudos crônicos utilizando a pré-ativação no desempenho neuromuscular e nas atividades funcionais são escassos. O estudo teve por objetivo comparar os efeitos de 12 sessões de ER com ações recíprocas e um modelo tradicional no desempenho funcional e proprioceptivo de indivíduos jovens. Quarenta e oito homens foram aleatorizados em 2 grupos: 1 treinamento recíproco (TRE, 3 séries; 10 repetições; flexão do joelho imediatamente seguida pela extensão do joelho; 2 treinamento tradicional (TRA, 3 séries; 10 repetições; extensão do joelho. As avaliações pré e pós foram caracterizadas por testes de equilíbrio, salto unipodal em distância (SUD e corrida em formato de “8” (CR8. Aplicou-se uma ANOVA 2X2 de modelos mistos para analisar diferenças entre as condições pré e pós e entre os grupos. No equilíbrio global e anteroposterior, não foram encontradas diferenças significantes entre os grupos TRE e TRA (p>0,05. Do mesmo modo, não foram encontradas diferenças pós-treinamento. O equilíbrio mediolateral no membro dominante não demonstrou diferenças significantes pós-treinamento (p=0,94, mas o membro não dominante demonstrou diferença significante entres os grupos (p<0,01. No SUD, houve aumentos significantes pós-treinamento nos grupos (p<0,01, mas sem diferença entre ambos (p=0,90. A CR8 apresentou diferença entre grupos (p=0,03, com melhor tempo de corrida do TRA pós-treinamento. O ER gerou transferências para o equilíbrio e testes funcionais, e o treinamento com ações recíprocas apresentou melhores indicativos para o SUD e equilíbrio mediolateral do joelho.

Melhoria de Desempenho em Segmentos Altamente Competitivos: a Gestão Baseada em Valor (GBV na Indústria Têxtil Brasileira

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Paschoal Tadeu Russo

2017-04-01

Full Text Available Este relato técnico tem como objetivo apresentar os benefícios gerados pela utilização da Gestão Baseada em Valor (GBV para a gestão do desempenho econômico de indústrias, de forma geral, mais especificamente no setor têxtil de não-vestuário brasileiro, um setor altamente competitivo, como uma forma de maximizar o retorno sobre o capital investido na empresa. A intervenção observada ocorreu no período de final de 2012 a 2015 quando a empresa estudada, com mais de 40 anos de existência e de gestão familiar, mudou sua estrutura organizacional, passando de funcional para descentralizada por unidades de negócio. Tal mudança causou necessidades de alterações do processo de avaliação do desempenho, o que permitiu a implantação da GBV. Essa implantação possibilitou a melhoria do processo de gestão, a melhoria dos sistemas de informação e, consequentemente, contribuiu com a melhoria do desempenho dos gestores e da organização. Entende-se que a GBV se apresenta como uma ferramenta que contribui para os processos de gestão que levam à criação de valor para as organizações e oferece elementos de mensuração do lucro econômico como uma medida do lucro residual aos custos de capital da organização

ESTIMATION OF GRASPING TORQUE USING ROBUST REACTION TORQUE OBSERVER FOR ROBOTIC FORCEPS

OpenAIRE

塚本, 祐介

2015-01-01

Abstract— In this paper, the estimation of the grasping torque of robotic forceps without the use of a force/torque sensor is discussed. To estimate the grasping torque when the robotic forceps driven by a rotary motor with a reduction gear grasps an object, a novel robust reaction torque observer is proposed. In the case where a conventional reaction force/torque observer is applied, the estimated torque includes not only the grasping torque, namely the reaction torque, but also t...

Comparison Between a Reference Torque Standard Machine and a Deadweight Torque Standard Machine to BE Used in Torque Calibration

Science.gov (United States)

Meng, Feng; Zhang, Zhimin; Lin, Jing

The paper describes the reference torque standard machine with high accuracy and multifunction, developed by our institute, and introduces the structure and working principle of this machine. It has three main functions. The first function is the hydraulic torque wrench calibration function. The second function is torque multiply calibration function. The third function is reference torque standard machine function. We can calibrate the torque multipliers, hydraulic wrenches and transducers by this machine. A comparison experiment has been done between this machine and a deadweight torque standard machine. The consistency between the 30 kNm reference torque machine and the 2000 Nm dead-weight torque standard machine under the claimed uncertainties was verified.

UM ESTUDO DA INFLUÊNCIA DA GESTÃO DE PESSOAS NO DESEMPENHO DO TRABALHADOR E NA MELHORIA DA QUALIDADE

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Crislaine Carvalho

2017-01-01

Full Text Available A qualidade é uma das principais preocupações presentes dentro das organizações, e estas estão sempre à procura de ferramentas que possam auxiliar nesse processo. A influência da gestão de pessoas no desempenho do trabalhador pode ser um diferencial para as empresas no mercado competitivo. Este trabalho tem a finalidade de apresentar o relacionamento entre a gestão de pessoas e a gestão da qualidade e seus reflexos no processo de melhoria contínua. Nesse contexto, foi feita uma revisão bibliográfica da evolução histórica da qualidade e os reflexos da gestão de pessoas nesse processo. Foi estudado também uma evolução do termo Gestão de Pessoas e suas diversas nomenclaturas adotadas ao longo do tempo, e as influências dessas nomenclaturas no relacionamento com os funcionários. Essa pesquisa trouxe resultados positivos a respeito da influência da gestão de pessoas na melhoria da qualidade, mostrando que os interesses da empresa e dos funcionários podem sim caminhar juntos, desde que ambos os lados estejam satisfeitos, o que confirmou a hipótese inicial desse trabalho.

GRAMÁTICA FUNCIONAL: DA ORAÇÃO RUMO AO DISCURSO

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Edson Rosa Francisco de Souza

2011-01-01

Full Text Available Este artigo busca apresentar um breve apanhado teórico sobre a Gramática Discursivo-Funcional, começando pelo modelo padrão de Gramática Funcional, desenvolvida por Simon Dik. O objetivo é mostrar a evolução do modelo funcional de Dik para o modelo de Gramática Discursivo Funcional de Hengeveld & Mackenzie (2006, 2008, apresentando-se as definições e as justificativas que embasam a expansão de um modelo funcional focado na oração (Dik, 1989; 1997 para um modelo funcional focado em uma unidade de análise mais ampla (o discurso, na qual as relações entre duas ou mais orações (ou porções de texto maiores são levadas em consideração. Palavras-chave: Funcionalismo; Discurso; Gramática Discursivo-Funcional.

La Gramática Discursivo-Funcional

NARCIS (Netherlands)

Hengeveld, K.; Mackenzie, J.L.

2011-01-01

La Gramática Discursivo-Funcional (GDF) es una teoría funcional del lenguaje de inspiración tipológica que presenta una organización descendente (top-down) con el objeto de alcanzar la adecuación psicológica y que toma el Acto Discursivo como unidad básica de análisis para lograr la adecuación

Magnetic Field and Torque Output of Packaged Hydraulic Torque Motor

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Liang Yan

2018-01-01

Full Text Available Hydraulic torque motors are one key component in electro-hydraulic servo valves that convert the electrical signal into mechanical motions. The systematic characteristics analysis of the hydraulic torque motor has not been found in the previous research, including the distribution of the electromagnetic field and torque output, and particularly the relationship between them. In addition, conventional studies of hydraulic torque motors generally assume an evenly distributed magnetic flux field and ignore the influence of special mechanical geometry in the air gaps, which may compromise the accuracy of analyzing the result and the high-precision motion control performance. Therefore, the objective of this study is to conduct a detailed analysis of the distribution of the magnetic field and torque output; the influence of limiting holes in the air gaps is considered to improve the accuracy of both numerical computation and analytical modeling. The structure and working principle of the torque motor are presented first. The magnetic field distribution in the air gaps and the magnetic saturation in the iron blocks are analyzed by using a numerical approach. Subsequently, the torque generation with respect to the current input and assembly errors is analyzed in detail. This shows that the influence of limiting holes on the magnetic field is consistent with that on torque generation. Following this, a novel modified equivalent magnetic circuit is proposed to formulate the torque output of the hydraulic torque motor analytically. The comparison among the modified equivalent magnetic circuit, the conventional modeling approach and the numerical computation is conducted, and it is found that the proposed method helps to improve the modeling accuracy by taking into account the effect of special geometry inside the air gaps.

Indicadores de desempenho e decisão sobre terceirização em rede pública de laboratórios

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Maria Angelica Borges dos Santos

2012-06-01

Full Text Available OBJETIVO: Elaborar indicadores de desempenho e terceirização em rede de laboratórios clínicos, baseados em sistemas de informações e registros administrativos públicos. MÉTODOS: A rede tinha 33 laboratórios com equipamentos automatizados, mas sem informatização, 90 postos de coleta e 983 funcionários, no município de Rio de Janeiro, RJ. As informações foram obtidas de registros administrativos do Sistema de Informações de Orçamentos Públicos para a Saúde e do Sistema de Informações Ambulatoriais e Hospitalares do Sistema Único de Saúde. Os indicadores (produção, produtividade, utilização e custos foram elaborados com dados colhidos como rotina de 2006 a 2008. As variações da produção, custos e preços unitários dos testes no período foram analisadas por índices de Laspeyres e de Paasche, específicos para medir a atividade dos laboratórios, e pelo Índice de Preços ao Consumidor Amplo do Instituto Brasileiro de Geografia e Estatística. RESULTADOS: A produção foi de 10.359.111 testes em 2008 (aumento de 10,6% em relação a 2006 e a relação testes/funcionário cresceu 8,6%. As despesas com insumos, salários e prestador conveniado aumentaram, respectivamente 2,3%, 45,4% e 18,3%. Os testes laboratoriais por consulta e internação cresceram 10% e 20%. Os custos diretos totalizaram R$ 63,2 milhões em 2008, com aumento de 22,2% em valores correntes no período. Os custos diretos deflacionados pelo Índice de Preços ao Consumidor Amplo (9,5% para o período mostram aumento do volume da produção de 11,6%. O índice de volume específico para a atividade, que considera as variações do mix de testes, mostrou aumento de 18,5% no preço unitário do teste e de 3,1% no volume da produção. CONCLUSÕES: Os indicadores, em especial os índices específicos de volume e preços da atividade, constituem uma linha de base de desempenho potencial para acompanhar laboratórios próprios e terceirizados. Os

A magneto-rheological fluid-based torque sensor for smart torque wrench application

Science.gov (United States)

Ahmadkhanlou, Farzad; Washington, Gregory N.

2013-04-01

In this paper, the authors have developed a new application where MR fluid is being used as a sensor. An MR-fluid based torque wrench has been developed with a rotary MR fluid-based damper. The desired set torque ranges from 1 to 6 N.m. Having continuously controllable yield strength, the MR fluid-based torque wrench presents a great advantage over the regular available torque wrenches in the market. This design is capable of providing continuous set toque from the lower limit to the upper limit while regular torque wrenches provide discrete set torques only at some limited points. This feature will be especially important in high fidelity systems where tightening torque is very critical and the tolerances are low.

Spin-orbit torque opposing the Oersted torque in ultrathin Co/Pt bilayers

Energy Technology Data Exchange (ETDEWEB)

Skinner, T. D., E-mail: tds32@cam.ac.uk; Irvine, A. C.; Heiss, D.; Kurebayashi, H.; Ferguson, A. J., E-mail: ajf1006@cam.ac.uk [Cavendish Laboratory, University of Cambridge, Cambridge CB3 0HE (United Kingdom); Wang, M.; Hindmarch, A. T.; Rushforth, A. W. [School of Physics and Astronomy, University of Nottingham, Nottingham NG7 2RD (United Kingdom)

2014-02-10

Current-induced torques in ultrathin Co/Pt bilayers were investigated using an electrically driven ferromagnetic resonance technique. The angle dependence of the resonances, detected by a rectification effect as a voltage, was analysed to determine the symmetries and relative magnitudes of the spin-orbit torques. Both anti-damping (Slonczewski) and field-like torques were observed. As the ferromagnet thickness was reduced from 3 to 1 nm, the sign of the sum of the field-like torque and Oersted torque reversed. This observation is consistent with the emergence of a Rashba spin orbit torque in ultra-thin bilayers.

Lóbulos frontales y funciones ejecutivas en transexuales

OpenAIRE

Orozco Calderón,Gabriela; Ostrosky Shejet,Feggy

2012-01-01

Una persona transexual se define como aquella que presenta una incongruencia entre el fenotipo físico y la identidad de género. Existen transexuales nacidos hombres pero con identidad de género de mujer. Se ha propuesto que uno de los orígenes de esta condición radica en los efectos que las hormonas esteroides sexuales tienen sobre el desarrollo cerebral a nivel prenatal y es posible que afecten las funciones cognitivas como las funciones ejecutivas. El objetivo fue evaluar funciones ejecutiv...

COMPETITIVIDADE NA DESTINAÇÃO TURÍSTICA: ANÁLISE DO DESEMPENHO REAL FRENTE AO DESEMPENHO PERCEBIDO PELOS GESTORES

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Silvio Luiz Gonçalves Vianna

2016-04-01

poder público para melhorar o desempenho de uma destinação turística a partir de um levantamento feito junto aos gestores da iniciativa privada que mostre em que pontos os investimentos serão melhor aproveitados. Palavras-chave: Turismo. Competitividade das Destinações Turísticas. Indicadores de Desempenho. Políticas Públicas.

Limited Angle Torque Motors Having High Torque Density, Used in Accurate Drive Systems

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R. Obreja

2011-01-01

Full Text Available A torque motor is a special electric motor that is able to develop the highest possible torque in a certain volume. A torque motor usually has a pancake configuration, and is directly jointed to a drive system (without a gear box. A limited angle torque motor is a torque motor that has no rotary electromagnetic field — in certain papers it is referred to as a linear electromagnet. The main intention of the authors for this paper is to present a means for analyzing and designing a limited angle torque motor only through the finite element method. Users nowadays require very high-performance limited angle torque motors with high density torque. It is therefore necessary to develop the highest possible torque in a relatively small volume. A way to design such motors is by using numerical methods based on the finite element method.

Análise da correlação entre pico de torque, desempenho funcional e frouxidão ligamentar em indivíduos normais e com reconstrução do ligamento cruzado anterior Functional performance and knee laxity in normal individuals and in individuals submitted to anterior cruciate ligament reconstruction

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Rodrigo Antunes de Vasconcelos

2009-04-01

Full Text Available OBJETIVO: Analisar a correlação entre os déficits musculares dos extensores e flexores do joelho através do pico de torque isocinético com os testes de salto monopodal, frouxidão ligamentar pós-operatória e questionário de função em indivíduos normais e indivíduos submetidos à reconstrução do LCA com enxerto autólogo do tendão patelar e dos tendões flexores. MÉTODOS: Foram recrutados 60 indivíduos, formando três grupos: 20 indivíduos sem lesões no joelho (grupo GC e dois grupos de 20 indivíduos submetidos à reconstrução do LCA com tendão patelar (grupo GTP ou tendões flexores (grupo GTF. RESULTADOS: Os resultados demonstraram correlação significativa entre déficits no pico de torque e testes funcionais no torque extensor nos grupos GTF e GC. Não foram observadas correlações significativas entre frouxidão ligamentar pós-operatória e questionário de Lysholm com os testes de salto e déficits no pico de torque. Em relação à diferença entre os grupos, foi observado que o grupo GTP demonstrou maior déficit do torque extensor, menor pontuação no questionário de Lysholm e maior percentagem dos indivíduos com índice de simetria entre membros (ISM OBJECTIVES: The aim of this study was to analyze the correlation between deficits in the isokinetic peak torque of the knee extensors and flexors with hop tests, postoperative knee laxity and functional scores in normal and ACL- reconstructed subjects with patellar tendon and hamstring tendon autografts. METHODS: Sixty male subjects were enrolled and subdivided into three groups: Twenty subjects without knee injuries (GC group and two groups of 20 subjects submitted to ACL reconstruction with patellar tendon (GTP group and hamstrings autograft (GTF group. RESULTS: The results showed significant correlation between knee extensors peak torque and performance in the hop tests for GTF and GC groups. There are no significantly correlations between post op knee laxity

Self-oscillation in spin torque oscillator stabilized by field-like torque

International Nuclear Information System (INIS)

Taniguchi, Tomohiro; Tsunegi, Sumito; Kubota, Hitoshi; Imamura, Hiroshi

2014-01-01

The effect of the field-like torque on the self-oscillation of the magnetization in spin torque oscillator with a perpendicularly magnetized free layer was studied theoretically. A stable self-oscillation at zero field is excited for negative β while the magnetization dynamics stops for β = 0 or β > 0, where β is the ratio between the spin torque and the field-like torque. The reason why only the negative β induces the self-oscillation was explained from the view point of the energy balance between the spin torque and the damping. The oscillation power and frequency for various β were also studied by numerical simulation

Accuracy of dental torque wrenches.

Science.gov (United States)

Wood, James S; Marlow, Nicole M; Cayouette, Monica J

2015-01-01

The aim of this in vitro study was to compare the actual torque of 2 manual wrench systems to their stated (target) torque. New spring- (Nobel Biocare USA, LLC) and friction-style (Zimmer Dental, Inc.) manual dental torque wrenches, as well as spring torque wrenches that had undergone sterilization and clinical use, were tested. A calibrated torque gauge was used to compare actual torque to target torque values of 15 and 35 N/cm. Data were statistically analyzed via mixed-effects regression model with Bonferroni correction. At a target torque of 15 N/cm, the mean torque of new spring wrenches (13.97 N/cm; SE, 0.07 N/cm) was significantly different from that of used spring wrenches (14.94 N/cm; SE, 0.06 N/cm; P torques of new spring and new friction wrenches (14.10 N/cm; SE, 0.07 N/cm; P = 0.21) were not significantly different. For torque measurements calibrated at 35 N/cm, the mean torque of new spring wrenches (35.29 N/cm; SE, 0.10 N/cm) was significantly different (P torque could impact the clinical success of screw-retained dental implants. It is recommended that torque wrenches be checked regularly to ensure that they are performing to target values.

CULTURA DE APRENDIZAGEM E DESEMPENHO ORGANIZACIONAL EM OSCIPS

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Sérgio Chaves Arruda

2015-07-01

Full Text Available O estudo objetiva analisar a relação entre a cultura de aprendizagem e o desempenho em uma organização da sociedade civil de interesse público (OSCIP na cidade de Fortaleza/CE, no tocante ao desempenho financeiro e do conhecimento, com suporte nas percepções dos variados agentes da organização. A base teórica são os fatores definidos por Marsick e Watkins (2003, acerca da relação entre a cultura de aprendizagem e o desempenho organizacional. Para isso, utilizou-se a metodologia quantitativa de pesquisa de natureza descritiva. O questionário utilizado junto aos 211 participantes da pesquisa foi o Dloq-A (YANG, 2003. Os resultados do estudo confirmam as hipóteses estabelecidas, indicando que a cultura de aprendizagem exerce significativa influência no desempenho organizacional no Instituto, na percepção dos respondentes.

Desempenho da marcha de idosos praticantes de psicomotricidade

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Sarah Lins dos Santos

2014-07-01

Full Text Available Estudo quase experimental realizado com quinze idosos, desenvolvido na Clínica Escola de Fisioterapia da Universidade Federal da Paraíba, em 2011. Objetivou-se avaliar o desempenho da marcha de idosos praticantes de atividades psicomotoras. Foi realizada uma entrevista estruturada centrada em dados sociais, clínicos e funcionais, com o intuito de poder correlacionar diversas informações que sustentassem o objetivo do estudo. A média no desempenho cognitivo foi de 19,4, na primeira avaliação e de 23,2, na segunda. A média no desempenho de atividades relacionadas à marcha foi de 11,6, na primeira avaliação, e de 15,5, na segunda, logo após a prática de atividades psicomotoras. Constatou-se uma melhora significativa no desempenho das atividades relacionadas à marcha, com irregularidades que persistiram na altura e na continuidade do passo, bem como no desvio da linha média.

Desempenho de um trator agrícola de pneus, funcionando com misturas de óleo diesel e óleo de soja reutilizado

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Wagner da Cunha Siqueira

2011-10-01

Full Text Available No Brasil, a forma de energia alternativa mais atraente tem sido a biomassa e, mais recentemente, os óleos vegetais residuais e in natura. Portanto, objetivou-se, com este trabalho, avaliar o desempenho na tomada de potência de um trator agrícola de pneus, utilizando misturas de óleo Diesel (OD com óleo de soja reutilizádo (OSR. Primeiramente, foi realizado um estudo de densidade das misturas, comportamento da temperatura do óleo Diesel no sistema de alimentação de combustível do motor e análises de viscosidades das misturas em estudo. Após as análises, verificou-se, por meio de ensaios dinamométricos, o desempenho do motor alimentado com misturas de OD com OSR, em diferentes proporções. As principais conclusões deste trabalho foram: a para as avaliações na tomada de potência, a mistura de 25% OD com 75% OSR apresentou a maior potência entre as demais misturas; b o consumo especifico e os torques demonstraram tendência a maiores valores com o acréscimo da percentagem de OSR às misturas.

Entrenamiento Cognitivo de las Funciones Ejecutivas en la Edad Escolar

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María Luisa Betancur-Caro

2016-02-01

Full Text Available En este artículo nuestro objetivo es evaluar y analizar el Rendimiento Académico de un niño en edad escolar a partir de un programa de entrenamiento cognitivo de las Funciones Ejecutivas. Realizamos el estudio de caso en tres momentos: evaluación inicial pretest con subpruebas de la Banfe y la ENI; identificamos el estado de las funciones ejecutivas, el entrenamiento cognitivo del Control Inhibitorio, la Fluidez y la Planeación, y la evaluación final postest con el mismo repertorio de la evaluación inicial, a fin de identificar los logros del entrenamiento cognitivo sobre las funciones ejecutivas y el rendimiento académico. Resultados y conclusiones: El entrenamiento cognitivo favoreció las funciones ejecutivas estimuladas; sin embargo, no logramos demostrar una relación concluyente entre las funciones ejecutivas y el rendimiento académico.

Entrenamiento Cognitivo de las Funciones Ejecutivas en la Edad Escolar

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María Luisa Betancur-Caro

2016-01-01

Full Text Available En este artículo nuestro objetivo es evaluar y analizar el Rendimiento Académico de un niño en edad escolar a partir de un programa de entrenamiento cognitivo de las Funciones Ejecutivas. Realizamos el estudio de caso en tres momentos: evaluación inicial pretest con subpruebas de la Banfe y la ENI; identificamos el estado de las funciones ejecutivas, el entrenamiento cognitivo del Control Inhibitorio, la Fluidez y la Planeación, y la evaluación final postest con el mismo repertorio de la evaluación inicial, a fin de identificar los logros del entrenamiento cognitivo sobre las funciones ejecutivas y el rendimiento académico. Resultados y conclusiones: El entrenamiento cognitivo favoreció las funciones ejecutivas estimuladas; sin embargo, no logramos demostrar una relación concluyente entre las funciones ejecutivas y el rendimiento académico.

Development of high torque belt CVT with torque converter; Torque converter tsuki daiyoryogata belt CVT no kaihatsu

Energy Technology Data Exchange (ETDEWEB)

Kurosawa, M; Fujikawa, T; Yoshida, K; Kobayahi, M [Nissan Motor Co. Ltd., Tokyo (Japan)

1997-10-01

Nissan has successfully developed a new belt CVT (Continuously Variable Transmission) with torque converter and has installed it 2L-class vehicle for the first time in the world. This paper describes about the technology of high torque transmission, the need of torque converter, the importance of electronic control and the introduce of driving mode. As the result the CVT has improved driving performance and fuel economy for current CVT and 4 speed automatic transmission. 13 figs., 2 tabs.

Consciência do déficit na doença de Alzheimer: diferenças entre os domínios cognitivo e funcional

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Tatiana Belfort

2013-09-01

Full Text Available OBJETIVOS: Revisar sistematicamente desenhos de estudo, instrumentos de avaliação e fatores relacionados ao comprometimento dos domínios cognitivo e funcional da consciência do déficit em pessoas com doença de Alzheimer (DA. MÉTODO: Pesquisa nas bases de dados PubMed e ISI de estudos sobre consciência do déficit na DA publicados entre 2008 e 2013. As palavras-chave utilizadas foram: "dementia", "Alzheimer", "awareness", "awareness of memory" e "awareness of functioning", "deficits", "cognition". RESULTADOS: Os 10 artigos selecionados utilizaram os conceitos "falta de consciência do déficit", "anosognosia", "insight", "falta de consciência das dificuldades cognitivas" e "consciência limitada das deficiências". A etiologia do comprometimento da consciência do déficit foi relacionada a fatores biológicos como gravidade clínica da doença, associações neuroanatômicas, alterações neuropsiquiátricas e fatores psicológicos e sociais. O desenho de estudo mais utilizado foi o corte transversal. No domínio cognitivo, a memória e as funções executivas foram as duas principais funções investigadas. No domínio funcional, foram encontradas associações com a disfunção executiva, declínio da interação social, depressão e a influência do desempenho ocupacional. CONCLUSÕES: As distintas hipóteses etiológicas, a operacionalização variável do conceito e a falta de instrumentos de avaliação padronizados impossibilitam a obtenção de resultados homogêneos. Essas dificuldades comprometem a compreensão e a investigação dos domínios cognitivo e funcional.

Using torque switch settings and spring pack characteristics to determine actuator output torques

International Nuclear Information System (INIS)

Black, B.R.

1992-01-01

Actuator output torque of motor operated valves is often a performance parameter of interest. It is not always possible to directly measure this torque. Torque spring pack deflection directly reflects actuator output torque and can be directly measured on most actuators. The torque spring pack may be removed from the actuator and tested to determine its unique force-deflection relationship. Or, a representative force-deflection relationship for the particular spring pack model may be available. With either relationship, measurements of torque spring pack deflection may then be correlated to corresponding forces. If the effective length of the moment arm within the actuator is known, actuator output torque can then be determined. The output torque is simply the product of the effective moment arm length and the spring pack force. This paper presents the reliability of this technique as indicated by testing. TU Electric is evaluating this technique for potential use in the future. Results presented in this paper should be considered preliminary. Applicability of these results may be limited to actuators and their components in a condition similar to those for which test data have been examined

Efficient micromagnetic modelling of spin-transfer torque and spin-orbit torque

Science.gov (United States)

Abert, Claas; Bruckner, Florian; Vogler, Christoph; Suess, Dieter

2018-05-01

While the spin-diffusion model is considered one of the most complete and accurate tools for the description of spin transport and spin torque, its solution in the context of dynamical micromagnetic simulations is numerically expensive. We propose a procedure to retrieve the free parameters of a simple macro-spin like spin-torque model through the spin-diffusion model. In case of spin-transfer torque the simplified model complies with the model of Slonczewski. A similar model can be established for the description of spin-orbit torque. In both cases the spin-diffusion model enables the retrieval of free model parameters from the geometry and the material parameters of the system. Since these parameters usually have to be determined phenomenologically through experiments, the proposed method combines the strength of the diffusion model to resolve material parameters and geometry with the high performance of simple torque models.

Optical Torque Wrench: Angular Trapping, Rotation, and Torque Detection of Quartz Microparticles

Science.gov (United States)

La Porta, Arthur; Wang, Michelle D.

2004-05-01

We describe an apparatus that can measure the instantaneous angular displacement and torque applied to a quartz particle which is angularly trapped. Torque is measured by detecting the change in angular momentum of the transmitted trap beam. The rotational Brownian motion of the trapped particle and its power spectral density are used to determine the angular trap stiffness. The apparatus features a feedback control that clamps torque or other rotational quantities. The torque sensitivity demonstrated is ideal for the study of known biological molecular motors.

Butterfly valve torque prediction methodology

International Nuclear Information System (INIS)

Eldiwany, B.H.; Sharma, V.; Kalsi, M.S.; Wolfe, K.

1994-01-01

As part of the Motor-Operated Valve (MOV) Performance Prediction Program, the Electric Power Research Institute has sponsored the development of methodologies for predicting thrust and torque requirements of gate, globe, and butterfly MOVs. This paper presents the methodology that will be used by utilities to calculate the dynamic torque requirements for butterfly valves. The total dynamic torque at any disc position is the sum of the hydrodynamic torque, bearing torque (which is induced by the hydrodynamic force), as well as other small torque components (such as packing torque). The hydrodynamic torque on the valve disc, caused by the fluid flow through the valve, depends on the disc angle, flow velocity, upstream flow disturbances, disc shape, and the disc aspect ratio. The butterfly valve model provides sets of nondimensional flow and torque coefficients that can be used to predict flow rate and hydrodynamic torque throughout the disc stroke and to calculate the required actuation torque and the maximum transmitted torque throughout the opening and closing stroke. The scope of the model includes symmetric and nonsymmetric discs of different shapes and aspects ratios in compressible and incompressible fluid applications under both choked and nonchoked flow conditions. The model features were validated against test data from a comprehensive flowloop and in situ test program. These tests were designed to systematically address the effect of the following parameters on the required torque: valve size, disc shapes and disc aspect ratios, upstream elbow orientation and its proximity, and flow conditions. The applicability of the nondimensional coefficients to valves of different sizes was validated by performing tests on 42-in. valve and a precisely scaled 6-in. model. The butterfly valve model torque predictions were found to bound test data from the flow-loop and in situ testing, as shown in the examples provided in this paper

Depressive symptoms and motor performance in the elderly: a population based study Sintomas depressivos e desempenho motor em idosos: estudo de base populacional

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Kleyton T. Santos

2012-08-01

intervalo de confiança de 95%. RESULTADOS: Para todos os testes motores, o desempenho motor foi negativamente associado à sintomatologia depressiva, independentemente do sexo, idade, saber ler e escrever, renda familiar per capita e atividade física. Idosos com sintomas depressivos possuem entre 58% e 82% mais limitação funcional, a depender do teste de desempenho motor. CONCLUSÕES: Conclui-se que existe uma relação inversa entre sintomas depressivos e desempenho motor em idosos.

Peak torque and rate of torque development in elderly with and without fall history.

Science.gov (United States)

Bento, Paulo Cesar Barauce; Pereira, Gleber; Ugrinowitsch, Carlos; Rodacki, André Luiz Felix

2010-06-01

Falls are one of the greatest concerns among the elderly. A number of studies have described peak torque as one of the best fall-related predictor. No studies have comprehensively focused on the rate of torque development of the lower limb muscles among elderly fallers. Then, the aim of this study was to determine the relationship between muscle peak torque and rate of torque development of the lower limb joints in elderly with and without fall history. It was also aimed to determine whether these parameters of muscle performance (i.e., peak torque and rate of torque development) are related to the number of falls. Thirty-one women volunteered to participate in the study and were assigned in one of the groups according to the number of falls over the 12 months that preceded the present. Then, participants with no fall history (GI; n=13; 67.6[7.5] years-old), one fall (GII; n=8; 66.0[4.9] years-old) and two or more falls (GIII; n=10; 67.8[8.8] years-old) performed a number of lower limb maximal isometric voluntary contractions from which peak torque and rate of torque development were quantified. Primary outcomes indicated no peak torque differences between experimental groups in any lower limb joint. The rate of torque development of the knee flexor muscles observed in the non-fallers (GI) was greater than that observed in the fallers (Pfalls (Pelderly to rapidly reorganise the arrangement of the lower limb may play a significant role in allowing the elderly to recover balance after a trip. Thus, training stimulus aimed to improve the rate of torque development may be more beneficial to prevent falls among the elderly than other training stimulus, which are not specifically designed to improve the ability to rapidly produce large amounts of torque. Copyright (c) 2010. Published by Elsevier Ltd.

Decoupled Speed and Torque Control of IPMSM Drives Using a Novel Load Torque Estimator

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ZAKY, M.

2017-08-01

Full Text Available This paper proposes decoupled speed and torque control of interior permanent magnet synchronous motor (IPMSM drives using a novel load torque estimator (LTE. The proposed LTE is applied for computing a load torque and yielding a feed-forward value in the speed controller to separate the torque control from the speed control. Indirect flux weakening using direct current component is obtained for high speed operation of the IPMSM drive, and its value for maximum torque per ampere (MTPA control in constant torque region is also used. LTE uses values of direct and quadrature currents to improve the behavior of the speed controller under the reference tracking and torque disturbances. The complete IPMSM drive by Matlab/Simulink is built. The effectiveness of the proposed control scheme using an experimental setup of the complete drive system implemented on a DSP-DS1102 control board is confirmed. Extensive results over a wide speed range are verified. The efficacy of the proposed method is confirmed in comparison to a conventional PI controller under both the reference speed tracking and load torque disturbance.

CULTURA DE APRENDIZAGEM E DESEMPENHO NAS TV’S CEARENSES

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Antonia Silva

2013-12-01

Full Text Available Este estudo insere-se no campo da Cultura de Aprendizagem Organizacional. Procura-se analisar a relação entre a Cultura de Aprendizagem (CA e o Desempenho Organizacional (DO em emissoras de TVs cearense, na percepção de seus colaboradores. Trata-se de uma survey descritiva, com uma abordagem quantitativa. Na coleta de dados, utilizou-se o questionário “DLOQ-A” desenvolvido por Yang (2003, contendo 27 itens, respondido por 95 indivíduos. Foi aplicado o método de Mínimos Quadrados Ordinários para analisar a correção entre as duas variáveis: cultura de aprendizagem organizacional e desempenho organizacional. Os resultados indicam que o Desempenho Organizacional nas emissoras está fortemente associado ao desempenho financeiro. Os fatores de Cultura de Aprendizagem que possuem maior capacidade explicativa encontram-se no nível individual (oportunidades para a aprendizagem contínua e no nível organizacional (estímulo a liderança estratégica para a aprendizagem; e desenvolvimento da visão sistêmica da organização. Em síntese, a CA exerce forte influência no desempenho organizacional com o coeficiente de regressão ( de 0,763.

Memoria, funciones ejecutivas y deterioro cognitivo en población anciana

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Yolanda Clemente

2015-08-01

Full Text Available Las funciones cognitivas hacen referencia a las funciones intelectivas o funciones mentales superiores. Suelen ser estos procesos los que primero sufren deterioro cognitivo asociado a la edad. El objetivo del presente estudio fue: analizar el estado de la memoria y las funciones ejecutivas en población anciana con y sin deterioro cognitivo; y comparar el estado cognitivo entre ancianos de un centro de personas mayores y ancianos en sus hogares. Se administró un test de screening para comprobar el nivel de deterioro cognitivo (Mini Examen Cognoscitivo MEC-35, para posteriormente, aplicar el Test de Alteración de Memoria (T@M y el Test de las Anillas. Los participantes fueron 24 sujetos, de los cuales 12 pertenecían a un centro de personas mayores y 12 residían en sus hogares. La edad media de los participantes fue de 78 años. El estudio permitió determinar la relación significativa entre el nivel de deterioro cognitivo y el estado de la memoria y las funciones ejecutivas. El sexo fue indiferente en la variable memoria, pero no en funciones ejecutivas. Finalmente, el hecho de que la persona resida en una institución no mostró diferencias significativas frente a aquellos que residen en sus hogares en cuanto al estado de la memoria y las funciones ejecutivas.

Game programmer's guide to Torque under the hood of the Torque game engine

CERN Document Server

Maurina , Edward F

2006-01-01

game programmer working with the Torque game engine must have ""The Game Programmer's Guide To Torque"": it teaches everything needed to design your own game, using experiences of game makers and industry veterans well versed in Torque technology. A Torque Game engine demo is included on an accompanying cd while step-by-step examples tell how to use it. Its focus on all the basics makes for an exceptional coverage for all levels of game programmer. -Bookwatch, August 2006

Torque sensor

Science.gov (United States)

Fgeppert, E.

1984-09-01

Mechanical means for sensing turning torque generated by the load forces in a rotary drive system is described. The sensing means is designed to operate with minimal effect on normal operation of the drive system. The invention can be employed in various drive systems, e.g., automotive engine-transmission power plants, electric motor-operated tools, and metal cutting machines. In such drive systems, the torque-sensing feature may be useful for actuation of various control devices, such as electric switches, mechanical clutches, brake actuators, fluid control valves, or audible alarms. The torque-sensing function can be used for safety overload relief, motor de-energization, engine fuel control transmission clutch actuation, remote alarm signal, tool breakage signal, etc.

Funciones expresivas (comportamiento motor y lenguaje), comportamiento emocional y funciones ejecutivas en la discapacidad intelectual

OpenAIRE

Grau Rubio, Claudia

2006-01-01

Se describen las bases neurológicas del comportamiento motor, lenguaje, funciones ejecutivas y comportamiento emocional en las personas con discapacidad intelectual; las dificultades asociadas y cómo se puede intervenir.

Momentum confinement at low torque

Energy Technology Data Exchange (ETDEWEB)

Solomon, W M [Princeton Plasma Physics Laboratory, Princeton University, Princeton, NJ 08543 (United States); Burrell, K H [General Atomics, PO Box 85608, San Diego, CA 92186-5608 (United States); De Grassie, J S [General Atomics, PO Box 85608, San Diego, CA 92186-5608 (United States); Budny, R [Princeton Plasma Physics Laboratory, Princeton University, Princeton, NJ 08543 (United States); Groebner, R J [General Atomics, PO Box 85608, San Diego, CA 92186-5608 (United States); Kinsey, J E [General Atomics, PO Box 85608, San Diego, CA 92186-5608 (United States); Kramer, G J [Princeton Plasma Physics Laboratory, Princeton University, Princeton, NJ 08543 (United States); Luce, T C [General Atomics, PO Box 85608, San Diego, CA 92186-5608 (United States); Makowski, M A [Lawrence Livermore National Laboratory, Livermore, CA 94550 (United States); Mikkelsen, D [Princeton Plasma Physics Laboratory, Princeton University, Princeton, NJ 08543 (United States); Nazikian, R [Princeton Plasma Physics Laboratory, Princeton University, Princeton, NJ 08543 (United States); Petty, C C [General Atomics, PO Box 85608, San Diego, CA 92186-5608 (United States); Politzer, P A [General Atomics, PO Box 85608, San Diego, CA 92186-5608 (United States); Scott, S D [Princeton Plasma Physics Laboratory, Princeton University, Princeton, NJ 08543 (United States); Zeeland, M A Van [General Atomics, PO Box 85608, San Diego, CA 92186-5608 (United States); Zarnstorff, M C [Princeton Plasma Physics Laboratory, Princeton University, Princeton, NJ 08543 (United States)

2007-12-15

Momentum confinement was investigated on DIII-D as a function of applied neutral beam torque at constant normalized beta {beta}{sub N}, by varying the mix of co (parallel to the plasma current) and counter neutral beams. Under balanced neutral beam injection (i.e. zero total torque to the plasma), the plasma maintains a significant rotation in the co-direction. This 'intrinsic' rotation can be modeled as being due to an offset in the applied torque (i.e. an 'anomalous torque'). This anomalous torque appears to have a magnitude comparable to one co neutral beam source. The presence of such an anomalous torque source must be taken into account to obtain meaningful quantities describing momentum transport, such as the global momentum confinement time and local diffusivities. Studies of the mechanical angular momentum in ELMing H-mode plasmas with elevated q{sub min} show that the momentum confinement time improves as the torque is reduced. In hybrid plasmas, the opposite effect is observed, namely that momentum confinement improves at high torque/rotation. GLF23 modeling suggests that the role of E x B shearing is quite different between the two plasmas, which may help to explain the different dependence of the momentum confinement on torque.

Low mass planet migration in magnetically torqued dead zones - I. Static migration torque

Science.gov (United States)

McNally, Colin P.; Nelson, Richard P.; Paardekooper, Sijme-Jan; Gressel, Oliver; Lyra, Wladimir

2017-12-01

Motivated by models suggesting that the inner planet forming regions of protoplanetary discs are predominantly lacking in viscosity-inducing turbulence, and are possibly threaded by Hall-effect generated large-scale horizontal magnetic fields, we examine the dynamics of the corotation region of a low-mass planet in such an environment. The corotation torque in an inviscid, isothermal, dead zone ought to saturate, with the libration region becoming both symmetrical and of a uniform vortensity, leading to fast inward migration driven by the Lindblad torques alone. However, in such a low viscosity situation, the material on librating streamlines essentially preserves its vortensity. If there is relative radial motion between the disc gas and the planet, the librating streamlines will no longer be symmetrical. Hence, if the gas is torqued by a large-scale magnetic field so that it undergoes a net inflow or outflow past the planet, driving evolution of the vortensity and inducing asymmetry of the corotation region, the corotation torque can grow, leading to a positive torque. In this paper, we treat this effect by applying a symmetry argument to the previously studied case of a migrating planet in an inviscid disc. Our results show that the corotation torque due to a laminar Hall-induced magnetic field in a dead zone behaves quite differently from that studied previously for a viscous disc. Furthermore, the magnetic field induced corotation torque and the dynamical corotation torque in a low viscosity disc can be regarded as one unified effect.

A method to accurately estimate the muscular torques of human wearing exoskeletons by torque sensors.

Science.gov (United States)

Hwang, Beomsoo; Jeon, Doyoung

2015-04-09

In exoskeletal robots, the quantification of the user's muscular effort is important to recognize the user's motion intentions and evaluate motor abilities. In this paper, we attempt to estimate users' muscular efforts accurately using joint torque sensor which contains the measurements of dynamic effect of human body such as the inertial, Coriolis, and gravitational torques as well as torque by active muscular effort. It is important to extract the dynamic effects of the user's limb accurately from the measured torque. The user's limb dynamics are formulated and a convenient method of identifying user-specific parameters is suggested for estimating the user's muscular torque in robotic exoskeletons. Experiments were carried out on a wheelchair-integrated lower limb exoskeleton, EXOwheel, which was equipped with torque sensors in the hip and knee joints. The proposed methods were evaluated by 10 healthy participants during body weight-supported gait training. The experimental results show that the torque sensors are to estimate the muscular torque accurately in cases of relaxed and activated muscle conditions.

A Method to Accurately Estimate the Muscular Torques of Human Wearing Exoskeletons by Torque Sensors

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Beomsoo Hwang

2015-04-01

Full Text Available In exoskeletal robots, the quantification of the user’s muscular effort is important to recognize the user’s motion intentions and evaluate motor abilities. In this paper, we attempt to estimate users’ muscular efforts accurately using joint torque sensor which contains the measurements of dynamic effect of human body such as the inertial, Coriolis, and gravitational torques as well as torque by active muscular effort. It is important to extract the dynamic effects of the user’s limb accurately from the measured torque. The user’s limb dynamics are formulated and a convenient method of identifying user-specific parameters is suggested for estimating the user’s muscular torque in robotic exoskeletons. Experiments were carried out on a wheelchair-integrated lower limb exoskeleton, EXOwheel, which was equipped with torque sensors in the hip and knee joints. The proposed methods were evaluated by 10 healthy participants during body weight-supported gait training. The experimental results show that the torque sensors are to estimate the muscular torque accurately in cases of relaxed and activated muscle conditions.

Design of a new torque standard machine based on a torque generation method using electromagnetic force

International Nuclear Information System (INIS)

Nishino, Atsuhiro; Ueda, Kazunaga; Fujii, Kenichi

2017-01-01

To allow the application of torque standards in various industries, we have been developing torque standard machines based on a lever deadweight system, i.e. a torque generation method using gravity. However, this method is not suitable for expanding the low end of the torque range, because of the limitations to the sizes of the weights and moment arms. In this study, the working principle of the torque generation method using an electromagnetic force was investigated by referring to watt balance experiments used for the redefinition of the kilogram. Applying this principle to a rotating coordinate system, an electromagnetic force type torque standard machine was designed and prototyped. It was experimentally demonstrated that SI-traceable torque could be generated by converting electrical power to mechanical power. Thus, for the first time, SI-traceable torque was successfully realized using a method other than that based on the force of gravity. (paper)

Momentum Confinement at Low Torque

International Nuclear Information System (INIS)

Solomon, W.M.; Burrell, K.H.; deGrassie, J.S.; Budny, R.; Groebner, R.J.; Heidbrink, W.W.; Kinsey, J.E.; Kramer, G.J.; Makowski, M.A.; Mikkelsen, D.; Nazikian, R.; Petty, C.C.; Politzer, P.A.; Scott, S.D.; Van Zeeland, M.A.; Zarnstorff, M.C.

2007-01-01

Momentum confinement was investigated on DIII-D as a function of applied neutral beam torque at constant normalized β N , by varying the mix of co (parallel to the plasma current) and counter neutral beams. Under balanced neutral beam injection (i.e. zero total torque to the plasma), the plasma maintains a significant rotation in the co-direction. This 'intrinsic' rotation can be modeled as being due to an offset in the applied torque (i.e. an 'anomalous torque'). This anomalous torque appears to have a magnitude comparable to one co-neutral beam source. The presence of such an anomalous torque source must be taken into account to obtain meaningful quantities describing momentum transport, such as the global momentum confinement time and local diffusivities. Studies of the mechanical angular momentum in ELMing H-mode plasmas with elevated q min show that the momentum confinement time improves as the torque is reduced. In hybrid plasmas, the opposite effect is observed, namely that momentum confinement improves at high torque/rotation. The relative importance of E x B shearing between the two is modeled using GLF23 and may suggest a possible explanation.

Electromagnetic torque on the toroidal plasma and the error-field induced torque

International Nuclear Information System (INIS)

Pustovitov, V. D.

2007-01-01

The electromagnetic torque on the toroidal plasma is calculated assuming a linear plasma response to the applied perturbation, which may be the error field or the field created by the correction coils, or both. The result is compared with recently published expressions for the error field induced torque (Zheng et al 2006 Nucl. Fusion 46 L9, Zheng and Kotschenreuther 2006 Phys. Rev. Lett. 97 165001), and the conclusions of these papers are revised. We resolve the problem of the torque resonance raised there. It is shown that the strong increase in the torque due to the static error field must occur at the resistive wall mode stability limit and not at the no-wall stability limit

Visualización de funciones de dos variables

Directory of Open Access Journals (Sweden)

Busto Caballero, Ana Isabel

2004-01-01

Full Text Available Los alumnos de la licenciatura en Administración y Dirección de Empresas tienen dentro de los contenidos del programa de la asignatura “Matemáticas Empresariales I”, el estudio de las funciones de varias variables: continuidad, derivabilidad, diferenciabilidad y optimización. Este tema es complicado de visualizar con tiza y pizarra, a diferencia del mismo estudio realizado para funciones reales de variable real. El objetivo de este trabajo es presentar una metodología para llevar el ordenador a clase y visualizar las gráficas de las funciones de dos variables y sus características específicas, que faciliten la comprensión del tema por parte del alumno, y conseguir que los resultados obtenidos analíticamente tengan un aspecto gráfico e intuitivo.

Desempenho de motor ciclo Diesel em bancada dinamométrica utilizando misturas diesel/biodiesel Performance of cycle Diesel engine in dynamometer using diesel/biodiesel mixtures

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Marcio Castellanelli

2008-03-01

Full Text Available Diante da previsão de escassez do petróleo, o éster etílico (biodiesel tem-se apresentado como excelente opção de combustível alternativo para motores ciclo Diesel. As características do biodiesel são semelhantes às do diesel em termos de viscosidade e poder calorífico, podendo ser utilizado sem adaptações nos motores. Para a realização deste trabalho, utilizou-se de motor ciclo Diesel, de injeção direta, com quatro cilindros, sem adaptações. O motor foi acoplado a um dinamômetro e sistemas de aquisição de dados auxiliares. Avaliaram-se os desempenhos de torque, de potência e de consumo específico de combustível para as seguintes misturas diesel/éster etílico de soja: B2, B5, B10, B20, B50, B75 e B100. O melhor desempenho registrado deu-se com a mistura B20.Given the prediction of the scarcity of oil, the ethyl ester (biodiesel has presented as an excellent alternative fuel option for cycle diesel engine. The characteristics of biodiesel are similar of diesel in terms of viscosity and the calorific power, being able to be used without adaptations in the engines. For the accomplishment of this work it was used a cycle diesel engine, of direct injection with four cylinders, without adaptations. The engine was connected to a dynamometer and acquisition systems of auxiliary data. The performances of torque, power and specific fuel consumption for the following mixtures diesel/soy ethyl ester had been evaluated: B2, B5, B10, B20, B50, B75 and B100. The best registered performance was given with the B20 mixture.

Thermomagnetic torque in hydrogen isotopes

International Nuclear Information System (INIS)

Cramer, J.A.

1975-01-01

The thermomagnetic torque has been measured in parahydrogen and ortho and normal deuterium for pressures from 0.10 to 2.0 torr and temperatures from 100 to 370 K. Since the torque depends on the precession of the molecular rotational magnetic moment around the field direction, coupling of the molecular nuclear spin to the rotational moment can affect the torque. Evidence of spin coupling effects is found for the torque in both deuterium modifications. In para hydrogen the torque at all temperatures and pressures exhibits behavior expected of a gas of zero nuclear spin molecules. Additionally, earlier data for hydrogen deuteride and for normal hydrogen from 105 to 374 K are evaluated and discussed. The high pressure limiting values of torque peak heights and positions for all these gases are compared with theory

Influence of Joint Angle on EMG-Torque Model During Constant-Posture, Torque-Varying Contractions.

Science.gov (United States)

Liu, Pu; Liu, Lukai; Clancy, Edward A

2015-11-01

Relating the electromyogram (EMG) to joint torque is useful in various application areas, including prosthesis control, ergonomics and clinical biomechanics. Limited study has related EMG to torque across varied joint angles, particularly when subjects performed force-varying contractions or when optimized modeling methods were utilized. We related the biceps-triceps surface EMG of 22 subjects to elbow torque at six joint angles (spanning 60° to 135°) during constant-posture, torque-varying contractions. Three nonlinear EMG σ -torque models, advanced EMG amplitude (EMG σ ) estimation processors (i.e., whitened, multiple-channel) and the duration of data used to train models were investigated. When EMG-torque models were formed separately for each of the six distinct joint angles, a minimum "gold standard" error of 4.01±1.2% MVC(F90) resulted (i.e., error relative to maximum voluntary contraction at 90° flexion). This model structure, however, did not directly facilitate interpolation across angles. The best model which did so achieved a statistically equivalent error of 4.06±1.2% MVC(F90). Results demonstrated that advanced EMG σ processors lead to improved joint torque estimation as do longer model training durations.

sócio-funcional em idosos

Directory of Open Access Journals (Sweden)

Francielli Brito da Fonseca

2008-01-01

Full Text Available Se trata de una investigación realizada con el objetivo de construir un instrumento de evaluación para ancianos. La investigación fue desarrollada entre marzo y septiembre de 2007, por medio de la revisión de literatura, identificación y análisis de diversos instrumentos/escalas propuestos para la evaluación funcional. A partir del análisis de nueve escalas, se construyó el Instrumento de Evaluación Socio-funcional en Ancianos, que se compone de dos partes: la primera, cuyo objetivo es obtener datos de identificación, representación del estado de salud y desempeño social de los ancianos; la segunda busca realizar la evaluación funcional propiamente dicha. El instrumento fue evaluado por cuatro jueces y después fue aplicado a diez ancianos con diversos grados de dependencia. Se reveló de fácil aplicación y útil en la identificación de los factores que intervienen en la salud de la persona anciana, así como, en la evaluación del grado de dependencia, ofreciendo subsidios para la planificación del trabajo en salud y asistencia a los ancianos.

Electron spin torque in atoms

International Nuclear Information System (INIS)

Hara, Takaaki; Senami, Masato; Tachibana, Akitomo

2012-01-01

The spin torque and zeta force, which govern spin dynamics, are studied by using monoatoms in their steady states. We find nonzero local spin torque in transition metal atoms, which is in balance with the counter torque, the zeta force. We show that d-orbital electrons have a crucial effect on these torques. Nonzero local chirality density in transition metal atoms is also found, though the electron mass has the effect to wash out nonzero chirality density. Distribution patterns of the chirality density are the same for Sc–Ni atoms, though the electron density distributions are different. -- Highlights: ► Nonzero local spin torque is found in the steady states of transition metal atoms. ► The spin steady state is realized by the existence of a counter torque, zeta force. ► D-orbital electrons have a crucial effect on the spin torque and zeta force. ► Nonzero local chiral density is found in spite of the washout by the electron mass. ► Chiral density distribution have the same pattern for Sc–Ni atoms.

Una aplicación de las funciones débilmente contractivas a problemas de valor en la frontera de funciones con valores en intervalos

Directory of Open Access Journals (Sweden)

Vladimir Angulo-Castillo

2014-01-01

Full Text Available Se estudia la existencia y unicidad de soluciones para problemas de valor en la frontera asociadas a ecuaciones diferenciales de funciones con valores en intervalos, usando la derivada de Hukuhara y algunos teoremas de punto fijo de funciones débilmente contractivas definidas en conjuntos par- cialmente ordenados.

Adaptive Engine Torque Compensation with Driveline Model

Directory of Open Access Journals (Sweden)

Park Jinrak

2018-01-01

Full Text Available Engine net torque is the total torque generated by the engine side, and includes the fuel combustion torque, the friction torque, and additionally the starter motor torque in case of hybrid vehicles. The engine net torque is utilized to control powertrain items such as the engine itself, the transmission clutch, also the engine clutch, and it must be accurate for the precise powertrain control. However, this net torque can vary with the engine operating conditions like the engine wear, the changes of the atmospheric pressure and the friction torque. Thus, this paper proposes the adaptive engine net torque compensator using driveline model which can cope with the net torque change according to engine operating conditions. The adaptive compensator was applied on the parallel hybrid vehicle and investigated via MATLAB Simcape Driveline simulation.

40 CFR 1065.310 - Torque calibration.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 32 2010-07-01 2010-07-01 false Torque calibration. 1065.310 Section... Conditions § 1065.310 Torque calibration. (a) Scope and frequency. Calibrate all torque-measurement systems including dynamometer torque measurement transducers and systems upon initial installation and after major...

Installation Torque Tables for Noncritical Applications

Science.gov (United States)

Rivera-Rosario, Hazel T.; Powell, Joseph S.

2017-01-01

The objective of this project is to define torque values for bolts and screws when loading is not a concern. Fasteners require a certain torque to fulfill its function and prevent failure. NASA Glenn Research Center did not have a set of fastener torque tables for non-critical applications without loads, usually referring to hand-tight or wrench-tight torqueing. The project is based on two formulas, torque and pullout load. Torque values are calculated giving way to preliminary data tables. Testing is done to various bolts and metal plates, torqueing them until the point of failure. Around 640 torque tables were developed for UNC, UNF, and M fasteners. Different lengths of thread engagement were analyzed for the 5 most common materials used at GRC. The tables were put together in an Excel spreadsheet and then formatted into a Word document. The plan is to later convert this to an official technical publication or memorandum.

¿Discapacidad o diversidad funcional?

Directory of Open Access Journals (Sweden)

Joan CANIMAS BRUGUÉ

2015-12-01

Full Text Available Hasta hoy disponemos de tres paradigmas para pensar lo que aún llamamos discapacidad: el médico, el social y el biopsicosocial (que ha intentado integrar y superar la confrontación entre los dos primeros. El Foro de Vida Independiente (FVI y los autores y activistas que ayudan a profundizar y a extender sus propuestas celebran el avance que ha supuesto el paradigma biopsicosocial, pero no lo comparten y proponen un nuevo modelo que llaman de la diversidad funcional, una versión hermenéutica del paradigma social. Este artículo intenta identificar los problemas que el modelo de la diversidad funcional plantea a la ética aplicada, y se centra en dos de ellos. El primero es: si lo que ahora consideramos deficiencia es interpretado únicamente como diversidad, ¿qué argumentos tendríamos para no respetar la decisión de unos padres de no corregir una deficiencia física, intelectual o del desarrollo de sus hijos, pudiéndolo hacer con una terapia eficaz, razonable y sin riesgos? ¿Y para impedir que les produzcan una deficiencia? El segundo problema es: ¿Cómo justificar la necesidad de discriminación positiva (más recursos y atenciones y más investigación médica y tecnológica a las personas con diversidad funcional e incluso de apoyo, si se considera que su manera de funcionar no es ni mejor ni peor que las otras?

Influência da velocidade no torque de remoção de tampas plásticas rosqueáveis para produtos farmacêuticos

Directory of Open Access Journals (Sweden)

Sandra Balan Mendoza Jaime

2012-04-01

Full Text Available O estudo teve por objetivo avaliar a influência da velocidade empregada durante a determinação do torque de aplicação e remoção de tampas plásticas rosqueáveis de polipropileno (PP, com vedante interno, aplicadas em frascos de vidro e de poli(tereftalato de etileno (PET para produtos farmacêuticos, com diâmetros de terminação de 24 e 28 mm. Foi verificada também a influência do material de embalagem (vidro ou PET e do diâmetro da terminação no torque de retenção estático e dinâmico (após simulação de transporte em intervalos de tempo após 24 e 48 horas e após 7, 14 e 28 dias da aplicação dos respectivos sistemas de fechamento. Verificou-se que a velocidade não apresenta influência no torque de aplicação desde que o valor máximo seja controlado durante o processo de fechamento da tampa. No torque de remoção imediato, entretanto, a velocidade influencia significativamente nos resultados, sendo recomendado, sempre que possível, a utilização de uma velocidade constante. Foi estabelecido para o estudo a velocidade de 5 rpm para evitar a influência desse parâmetro nos resultados de torque obtidos. O material de embalagem e o diâmetro da terminação evidenciaram influência significativa nos resultados de torque de retenção estático e dinâmico, sendo observados valores superiores para os frascos de vidro comparativamente aos frascos de PET. Esse desempenho pode estar associado às diferenças nas propriedades viscoelásticas e na força de fricção ou atrito entre os materiais da tampa com vedante e a embalagem.

14 CFR 27.361 - Engine torque.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Engine torque. 27.361 Section 27.361... STANDARDS: NORMAL CATEGORY ROTORCRAFT Strength Requirements Flight Loads § 27.361 Engine torque. (a) For turbine engines, the limit torque may not be less than the highest of— (1) The mean torque for maximum...

Charge-induced spin torque in Weyl semimetals

Science.gov (United States)

Kurebayashi, Daichi; Nomura, Kentaro

In this work, we present phenomenological and microscopic derivations of spin torques in magnetically doped Weyl semimetals. As a result, we obtain the analytical expression of the spin torque generated, without a flowing current, when the chemical potential is modulated. We also find that this spin torque is a direct consequence of the chiral anomaly. Therefore, observing this spin torque in magnetic Weyl semimetals might be an experimental evidence of the chiral anomaly. This spin torque has also a great advantage in application. In contrast to conventional current-induced spin torques such as the spin-transfer torques, this spin torque does not accompany a constant current flow. Thus, devices using this operating principle is free from the Joule heating and possibly have higher efficiency than devices using conventional current-induced spin torques. This work was supported by JSPS KAKENHI Grant Number JP15H05854 and JP26400308.

Impacto das Competências de Equipes sobre o Desempenho

Directory of Open Access Journals (Sweden)

Katia Puente-Palacios

2018-03-01

Full Text Available Resumo As competências para o trabalho têm sido tradicionalmente compreendidas como atributos de indivíduos; entretanto, estudos mais recentes tornam pertinente defender a sua ocorrência como atributos coletivos. O objetivo deste estudo foi demonstrar que competências individuais podem transformar-se em competências coletivas e, nesse nível, predizer o desempenho da equipe. A testagem empírica foi realizada em 51 aeródromos brasileiros, totalizando 106 equipes (entre 3 e 32 integrantes. Instrumentos respondidos pelos membros focaram nas competências enquanto os respondidos pelos lideres indagaram sobre o desempenho das equipes. Os resultados revelaram que as competências coletivas explicam aproximadamente 20% do desempenho das equipes. Disso depreende-se que as competências podem se manifestar como atributos coletivos que predizem resultados de equipes de trabalho.

Aborto entre alunas e funcionárias de uma universidade brasileira

Directory of Open Access Journals (Sweden)

Hardy Ellen

1993-01-01

Full Text Available No Brasil existem poucas informações sobre o aborto provocado e suas características na população. A dificuldade em se obter dados confiáveis deve-se: à sua ilegalidade, e também ao fato de que a maioria dos estudos é realizada em hospitais. Assim, em 1990, foi realizada pesquisa entre alunas da graduação e funcionárias de uma universidade brasileira. Os dados foram obtidos por meio de questionário, auto-respondido, para devolução por correio, anonimamente. Os resultados apresentados referem-se à freqüência do aborto provocado nesta população. Encontrou-se que quatro vezes menos alunas do que funcionárias tinham engravidado alguma vez (15% e 65%; 9% das alunas e 14% das funcionárias tiveram aborto provocado. Entre as mulheres que engravidaram alguma vez, as alunas tiveram mais aborto provocado do que as funcionárias (59% e 20%. Quando controladas por grupo etário as diferenças entre as alunas e funcionárias mantiveram-se. Entretanto, entre as alunas, o aborto provocado foi mais freqüente entre as mais jovens.

Spin Orbit Torque in Ferromagnetic Semiconductors

KAUST Repository

Li, Hang

2016-06-21

Electrons not only have charges but also have spin. By utilizing the electron spin, the energy consumption of electronic devices can be reduced, their size can be scaled down and the efficiency of `read\\' and `write\\' in memory devices can be significantly improved. Hence, the manipulation of electron spin in electronic devices becomes more and more appealing for the advancement of microelectronics. In spin-based devices, the manipulation of ferromagnetic order parameter using electrical currents is a very useful means for current-driven operation. Nowadays, most of magnetic memory devices are based on the so-called spin transfer torque, which stems from the spin angular momentum transfer between a spin-polarized current and the magnetic order parameter. Recently, a novel spin torque effect, exploiting spin-orbit coupling in non-centrosymmetric magnets, has attracted a massive amount of attention. This thesis addresses the nature of spin-orbit coupled transport and torques in non-centrosymmetric magnetic semiconductors. We start with the theoretical study of spin orbit torque in three dimensional ferromagnetic GaMnAs. Using the Kubo formula, we calculate both the current-driven field-like torque and anti-damping-like torque. We compare the numerical results with the analytical expressions in the model case of a magnetic Rashba two-dimensional electron gas. Parametric dependencies of the different torque components and similarities to the analytical results of the Rashba two-dimensional electron gas in the weak disorder limit are described. Subsequently we study spin-orbit torques in two dimensional hexagonal crystals such as graphene, silicene, germanene and stanene. In the presence of staggered potential and exchange field, the valley degeneracy can be lifted and we obtain a valley-dependent Berry curvature, leading to a tunable antidamping torque by controlling the valley degree of freedom. This thesis then addresses the influence of the quantum spin Hall

Números polares de P en el cuerpo de funciones hermitianas

OpenAIRE

Wilson Olaya León

2008-01-01

En este artículo presentamos una caracterización de los números polares (o no lagunas) del lugar infinito en el cuerpo de funciones hermitia- nas. Más aún, mostraremos que en dicho cuerpo de funciones los números polares de P∞ determinan una base explícita para el espacio vectorial aso- ciado al divisor mP∞ .

Vendaje Funcional para la Fascitis Plantar

OpenAIRE

Julián Rochina, Iván

2012-01-01

El profesor Vicente Tormo aplica un vendaje funcional que aproxima a su centro geométrico las estructuras que configuran la planta del pie, con el objetivo de mantener relajada la fascia plantar durante la bipedestación.

A força de preensão manual é boa preditora do desempenho funcional de idosos frágeis: um estudo correlacional múltiplo The hand-grip forecasts the functional performance of fragile elder subjects: a multiple-correlation study

Directory of Open Access Journals (Sweden)

Amandio A.R. Geraldes

2008-02-01

Full Text Available A força de preensão manual (FPM associa-se com a funcionalidade de idosos, mas há dúvidas sobre o valor dessa relação em todas as situações. O estudo observou a correlação entre FPM de idosos residentes em instituições de cuidados permanentes (asilos e o desempenho funcional (DF em tarefas específicas e inespecíficas para as mãos. Participaram 12 homens (70±6 anos; 64±9 kg; 160±10 cm e sete mulheres (77±11 anos; 49±10 kg; 147±10 cm. A FPM foi medida com dinamômetro hidráulico. As tarefas motoras propostas foram: caminhar 10 m na velocidade máxima (C10, timed up & go test (TUGT, colocar e retirar chave de fechadura (TCCF e tirar e recolocar lâmpada em um bocal (TCLB. O teste de Wilcoxon revelou que os homens apresentaram melhores desempenhos que as mulheres em todos as medidas, exceto IMC, TCCF e TCLB (pHand-grip strength (HGS has been used to predict functional limitation in the elderly. However, this relationship in all situations is doubtful. The purpose of the study was to observe the association between HGS and functional performance (FP, in specific and not specific tasks among 19 long-term home elderly residents, 12 men (70±6 yrs; 64±9 kg; 160±10 cm and 7 women (77±11 yrs; 49±10 kg; 147±10 cm. HGS was measured by a hydraulic hand dynamometer. The FP was measured by the time to perform the following tasks: 1 habitual gait speed (HGS; 2 timed up & go test (TUGT; 3 opening a lock with a key (OLK; 4 to take off and put in a light bulb (TPB. The Wilcoxon test revealed that men were better than women in all measurements except for the IMC, OLK and TPL (p<0.05. The Spearman coefficients showed significant correlation between HGS and three FP tests: TPL (r=-.54; p=.018; TUGT (r=-.67; p=.002 and HGS (r=-.69; p=.001. The multiple correlation showed good correlation between the HGS and all FP tests (R=.66; R²=.44; p<.04. These results suggest that HGS may be a good predictor for FP, especially for fragile and

Capacidad funcional y salud: orientaciones para cuidar al adulto mayor

Directory of Open Access Journals (Sweden)

CLARA INÉS GIRALDO M

2008-07-01

Full Text Available Objetivo: valorar la salud y la capacidad funcional de ancianos con dependencia funcional para el autocuidado, como elementos para orientar el cuidado de enfermería y el cuidado familiar en casa. Metodología: estudio descriptivo transversal en 40 personas de 65 y más años con dependencia funcional, cuidados por familiar, en Envigado Colombia; muestreo por conveniencia. Valoración de la capacidad funcional con el índice de Katz y la escala de Lawton y Brody, ajustados según grupo de Neurociencias, Universidad de Antioquia. Hallazgos: población entre 67 y 98 años, edad promedio 84,08 años; 82,5% mujeres. Sistemas orgánicos más afectados: cardiovascular, osteomuscular y neurológico; entre 47,5% y 27,5% de los ancianos los tenían comprometidos. Se identificaron dos comportamientos: los hombres, y las personas de edad más avanzada, con mayores grados de dependencia en las actividades básicas e instrumentales; no se determinó asociación estadística por el pequeño tamaño muestral. Las actividades básicas estaban afectadas así: entre el 67,5% y el 55% de los ancianos requería ayuda; y las actividades instrumentales estuvieron comprometidas: entre el 95% y el 75% de los ancianos son totalmente dependientes en ellas. Conclusiones: Enfermería ha de considerar la valoración de la capacidad funcional articulada al estado de salud integral de los ancianos, para orientar su cuidado y apoyar a los cuida-dores familiares. Esto además previene dependencias de cuidado innecesarias que estarían en contra de las aspiraciones del adulto mayor como individuo autónomo e independiente. Es tarea de profesionales en enfermería capacitar a cuidadores familiares sobre valoración de la capacidad funcional.

APRENDIZAGEM INDIVIDUAL, SUPORTE ORGANIZACIONAL E DESEMPENHO PERCEBIDO: UM ESTUDO COM DOCENTES UNIVERSITÁRIOS

Directory of Open Access Journals (Sweden)

Pérola Cavalcante Dourado

2018-03-01

Full Text Available Resumo: O estudo analisou as relações entre a percepção de aprendizagem de competências e de desempenho de docentes de nível superior. Além disso, testou o papel moderador do suporte organizacional na relação entre a aprendizagem individual e desempenho docente. Participaram do estudo 275 docentes de uma universidade pública federal, que responderam ao inventário de percepção de aprendizagem de competências, suporte à transferência e desempenho docente (ASOD. Foram realizadas análises confirmatórias e testados os modelos de predição e moderação. Uma das conclusões do estudo foi que a aprendizagem docente nas atividades de ensino, pesquisa, extensão e gestão predizem a percepção de desempenho em cada uma das atividades respectivamente. Não foram encontradas evidências de que o suporte modera as relações entre as aprendizagens e a percepção de desempenho docente.

Measuring the uncertainty of tapping torque

DEFF Research Database (Denmark)

Belluco, Walter; De Chiffre, Leonardo

An uncertainty budget is carried out for torque measurements performed at the Institut for Procesteknik for the evaluation of cutting fluids. Thirty test blanks were machined with one tool and one fluid, torque diagrams were recorded and the repeatability of single torque measurements was estimat...

Análise da assimetria funcional hemisférica de crianças com epilepsia parcial e QI normal pelo desempenho nos subtestes do WISC

OpenAIRE

Muszkat,Mauro; Vincenzo,Neyde Santacchi de; Masuko,Alice; Reami,Denilce O.; Campos,Carlos J. Reis de

1991-01-01

Foram avaliadas 26 crianças, sem deficiência mental, com média de idade de 9±2 anos, com epilepsia parcial sem lesão cerebral evidenciável à TCC e com atividade paroxistica no EEG intercrítico localizada apenas em um hemisfério cerebral. Essas crianças foram submetidas à Escala de Inteligência Wechsler para Crianças (WISC) e à análise dos vários subtestes verbais e execução em relação à localização hemisférica da descarga no EEG. Os dados foram comparados ao desempenho no WISC de um grupo de ...

Evaluación funcional en ancianos intervenidos de fractura de cadera

Directory of Open Access Journals (Sweden)

Silvia Montalbán-Quesada

2012-10-01

Full Text Available Estudio observacional prospectivo en pacientes mayores de 65 años intervenidos de fractura de cadera. El objetivo fue conocer la evolución funcional de los pacientes a los tres meses del alta hospitalaria, identificar variables relacionadas con dicha recuperación funcional, describir la mortalidad e institucionalización asociadas al proceso. Se analizaron variables demográficas como edad, sexo, convivencia. Otros aspectos registrados fueron: comorbilidad, deterioro cognitivo, capacidad para caminar, nivel de dependencia según índice de Barthel, institucionalización y mortalidad. Se recogió la información al ingreso y a los 3 meses del alta. El 89,6% de la muestra, fueron mujeres, la edad media fue de 83,56 años. El 40% de los pacientes recuperaron la independencia previa registrándose una mortalidad del 16,7% así como una leve progresión hacia la institucionalización. La capacidad funcional y el deterioro cognitivo del paciente, previos a la fractura condicionan su recuperación funcional y dependencias posteriores.

¿Pueden mejorarse las funciones ejecutivas en adultos jóvenes?

Directory of Open Access Journals (Sweden)

María Jesús Maraver

2017-10-01

Full Text Available Al igual que un controlador aéreo regula el funcionamiento de un ajetreado aeropuerto, las funciones ejecutivas son el sistema de control de nuestro comportamiento, permitiéndonos planificar y regular nuestras acciones (motoras o cognitivas, realizar múltiples tareas y recordar sólo aquella información que es relevante. Teniendo en cuenta su importancia, han sido muchos los intentos de demostrar si las funciones ejecutivas se pueden entrenar. En nuestro trabajo investigamos el efecto de dos tipos de entrenamiento de las funciones ejecutivas y demostramos que sí es posible mejorarlas. Además, comprobamos que una mayor motivación durante el entrenamiento está asociada a mayores mejoras.

Real time implementation of viable torque and flux controllers and torque ripple minimization algorithm for induction motor drive

International Nuclear Information System (INIS)

Vasudevan, M.; Arumugam, R.; Paramasivam, S.

2006-01-01

Field oriented control (FOC) and direct torque control (DTC) are becoming the industrial standards for induction motors torque and flux control. This paper aims to give a contribution for a detailed comparison between these two control techniques, emphasizing their advantages and disadvantages. The performance of these two control schemes is evaluated in terms of torque and flux ripple and their transient response to step variations of the torque command. Moreover, a new torque and flux ripple minimization technique is also proposed to improve the performance of the DTC drive. Based on the experimental results, the analysis has been presented

Development of a Portable Torque Wrench Tester

Science.gov (United States)

Wang, Y.; Zhang, Q.; Gou, C.; Su, D.

2018-03-01

A portable torque wrench tester (PTWT) with calibration range from 0.5 Nm to 60 Nm has been developed and evaluated for periodic or on-site calibration of setting type torque wrenches, indicating type torque wrenches and hand torque screwdrivers. The PTWT is easy to carry with weight about 10 kg, simple and efficient operation and energy saving with an automatic loading and calibrating system. The relative expanded uncertainty of torque realized by the PTWT was estimated to be 0.8%, with the coverage factor k=2. A comparison experiment has been done between the PTWT and a reference torque standard at our laboratory. The consistency between these two devices under the claimed uncertainties was verified.

Gestão de Recursos Humanos e Avaliação de Desempenho por Competências: análise do processo em uma empresa do Vale do Paraíba

Directory of Open Access Journals (Sweden)

Andréa Ladeira Campos

2014-07-01

Full Text Available Novas ferramentas de gestão estratégica de recursos humanos (RH estão sendo utilizadas como forma de captar, valorizar e reter o capital humano nas organizações, capacitando-as para enfrentar as crescentes adversidades e concorrências do mercado. Dentre essas ferramentas, pode-se citar a gestão e a avaliação de desempenho dos funcionários baseando-se em suas competências, cuja conceituação e exemplificação são objetivos deste trabalho. O programa do ciclo das “5 Conversas”, aplicado em uma empresa química instalada no Vale do Paraíba, é um exemplo de projeto que abrange: desenho de objetivos individuais atrelados aos objetivos corporativos; acompanhamento dos resultados; avaliação de desempenho, cuja nota é atrelada ao pagamento de bônus e méritos; e desenvolvimento de plano de sucessão e de carreira. De maneira geral, o estudo traz uma revisão bibliográfica acerca dos conceitos de gestão e avaliação por desempenho, competências, plano de sucessão e de recompensas, entre outros, além da descrição de todas as fases do programa “5 Conversas” através pesquisa exploratória em materiais disponibilizados pela empresa. Relacionando-se os conceitos definidos por diversos autores e a descrição do programa da empresa, é possível aprofundar os conhecimentos sobre o tema e conhecer o exemplo de um programa que pode ser considerado benchmarking para outras organizações e profissionais da área e concluir sobre a preocupação da referida empresa com seus talentos humanos.

14 CFR 23.361 - Engine torque.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Engine torque. 23.361 Section 23.361... Engine torque. (a) Each engine mount and its supporting structure must be designed for the effects of— (1) A limit engine torque corresponding to takeoff power and propeller speed acting simultaneously with...

14 CFR 25.361 - Engine torque.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Engine torque. 25.361 Section 25.361... STANDARDS: TRANSPORT CATEGORY AIRPLANES Structure Supplementary Conditions § 25.361 Engine torque. (a) Each engine mount and its supporting structure must be designed for the effects of— (1) A limit engine torque...

Torque limit of PM motors for field-weakening region operation

Science.gov (United States)

Royak, Semyon [Beachwood, OH; Harbaugh, Mark M [Richfield, OH

2012-02-14

The invention includes a motor controller and technique for controlling a permanent magnet motor. In accordance with one aspect of the present technique, a permanent magnet motor is controlled by receiving a torque command, determining a physical torque limit based on a stator frequency, determining a theoretical torque limit based on a maximum available voltage and motor inductance ratio, and limiting the torque command to the smaller of the physical torque limit and the theoretical torque limit. Receiving the torque command may include normalizing the torque command to obtain a normalized torque command, determining the physical torque limit may include determining a normalized physical torque limit, determining a theoretical torque limit may include determining a normalized theoretical torque limit, and limiting the torque command may include limiting the normalized torque command to the smaller of the normalized physical torque limit and the normalized theoretical torque limit.

Proposta de indicadores para avaliação de desempenho dos Sistemas de Gestão Ambiental e de Segurança e Saúde no Trabalho de Empresas do ramo de engenharia consultiva

Directory of Open Access Journals (Sweden)

Clarissa Lima Almeida

2014-12-01

Full Text Available O processo de implantação de um sistema de gestão agrega valor à cultura organizacional, pois desenvolve competências relacionadas ao planejamento e execução das atividades, prioriza a capacidade de trabalho em equipe e promove a confiabilidade do sistema produtivo. Deste modo, uma das principais ferramentas utilizadas na política econômica das organizações tem sido a implementação de um Sistema de Gestão Ambiental (SGA. Do mesmo modo, o crescente número de acidentes repercutidos na mídia fez com que as organizações buscassem nos Sistemas de Gestão de Segurança e Saúde no Trabalho (SGSST o instrumento para alcançar melhores resultados na área de SST. O uso dos indicadores de avaliação de desempenho auxilia as organizações a quantificar e relatar o desempenho de seus sistemas de gestão. Diante disso, o objetivo deste trabalho foi propor um conjunto de indicadores de avaliação de desempenho para os SGA e SGSST de uma empresa certificada pelas normas NBR ISO 14001:2004 e OHSAS 18001:2007, a fim de melhorar o desempenho destes sistemas, contribuindo com seus processos de melhoria contínua. Para isso, foi realizado um estudo de caso em uma empresa de engenharia consultiva, em que foram levantados os dados necessários para viabilizar a elaboração e proposta dos indicadores, por meio, principalmente, de entrevistas, aplicação de questionário aos funcionários e acompanhamento às auditorias realizadas na empresa. Desta forma, foram propostos 23 indicadores, sendo 11 para o SGA e 12 para o SGSST. Os indicadores propostos podem ser empregados em SGA e SGSST de empresas de qualquer ramo de atividade, por se tratar de indicadores de fácil implementação e controle.

Funciones de enfermería en la unidad quirúrgica de nefrología

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Yanela Díaz Oquendo

Full Text Available Los cuidados que se desarrollan en la unidad quirúrgica de Nefrología requieren de un personal de enfermería con capacidad para responder a las diferentes funciones de acuerdo al nivel profesional alcanzado y a las necesidades que requieren los pacientes con afecciones renales. Objetivos: Definir las funciones de enfermería en la unidad quirúrgica por niveles de formación. Material y métodos: Se realizó una investigación de desarrollo tecnológico en el Instituto de Nefrología y Hospital Hermanos Armejeiras en el período 2010-2012. Se utilizó la metodología DEFUN (delimitación de funciones y como técnicas cualitativas se usaron la revisión documental y la consulta a expertos. El universo se conformó de 24 profesionales entre enfermeros técnicos, licenciados y médicos de la especialidad; 11 profesionales conformaron el comité de expertos con los cuales se realizó un taller para la identificación y propuesta preliminar de las funciones. Se aplicó el método Delphi para la validación y propuesta de las funciones a 13 profesionales que formaron parte del panel de expertos. Resultados: La propuesta de las funciones se realizó sobre la base de las ya descritas para el licenciado y técnico en enfermería contenidas en la Resolución Ministerial 396/07, obteniéndose de 19 funciones propuestas para el licenciado en enfermería se aceptaron 17 y para el técnico en enfermería de 15 propuestas fueron aceptadas 14 funciones. Conclusiones: Quedan definas las funciones de enfermería por niveles de formación lo cual amplia el perfil de desempeño en correspondencia con el desarrollo alcanzado por la especialidad en el país.

Funciones ejecutivas: nociones del desarrollo desde una perspectiva neuropsicológica

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Esperanza Bausela Herreras

2014-06-01

Full Text Available Desde la perspectiva del desarrollo podemos observar como los niños van siendo cada más capaces de controlar por sí mimos sus propias acciones, respuestas y regular su propia conducta (autorregulación de la conducta o como pasan de una moral heterónoma a una moral autónoma. Esta capacidad de autorregulación de la conducta va ligada al desarrollo de procesos cognitivos de orden superior (memoria de trabajo, planificación, inhibición de respuestas automáticas..., relacionados todas ellos con un mismo constructo, Funciones ejecutivas. El objetivo de este artículo es analizar cómo se ha conceptualizado este constructo, centrándonos en uno de las paradojas que ha dominado la literatura en la última década. Desde esta perspectiva se consideran las Funciones ejecutivas como una unidad y al mismo tiempo integrada por una diversidad de funciones independientes. Esbozaremos, de forma más concreta, las líneas generales del modelo jerárquico propuesto por Miyake y colaboradores. Para estos autores las tres dimensiones que integran las Funciones ejecutivas son: flexibilidad atencional, control inhibitorio y memoria de trabajo. En coherencia con este modelo, analizamos el sustrato neurológico en el que se sustentan. Finalmente, comparamos diferentes teorías del desarrollo de las Funciones ejecutivas con el modelo jerárquico propuesto por Miyake y colaboradores.

14 CFR 29.361 - Engine torque.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Engine torque. 29.361 Section 29.361... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Strength Requirements Flight Loads § 29.361 Engine torque. The limit engine torque may not be less than the following: (a) For turbine engines, the highest of— (1) The...

TRAINING-INDUCED CHANGES IN THE TOPOGRAPHY OF MUSCLE TORQUES AND MAXIMAL MUSCLE TORQUES IN BASKETBALL PLAYERS

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Krzysztof Buśko

2012-01-01

Full Text Available The aim of the study was to detect changes in the maximal muscle torques in male basketball players during a two-year training cycle. We verified the hypothesis that different workloads applied during the preparation and competition periods would result in changes in the maximal muscle torques of the athletes (increase during the former and decrease or no change during the latter period accompanied by no alteration of the percent muscle topography of all the muscle groups tested. The examinations were conducted on nine senior male basketball players from the Polish national team. Estimations of the muscle torques in static conditions were performed at the end of the preparation (measurements I and III and competition (measurements II and IV periods of a two-year training cycle. Eleven muscle groups were studied including flexors and extensors of the trunk and flexors and extensors of the shoulder, the elbow, the hip, the knee, and the ankle. Muscle torques of the shoulder and the elbow insignificantly decreased except for the muscle torque of the flexors of the shoulder. Muscle torques of the flexors and extensors of the trunk as well as of the flexors and extensors of the hip, the knee, and the ankle increased between measurements I and III and between measurements I and IV with the only exception being the muscle torque of the flexors of the knee (which significantly decreased by 7.4% In the case of the flexors and extensors of the trunk and the flexors and extensors of the hip, the changes appeared to be significant. The sum of the muscle torques of the upper limbs markedly decreased between the preparation (measurement I and competition (measurement IV periods. The sum of the muscle torques of the trunk and the lower limbs and the sum of the muscle torques of the eleven muscle groups significantly increased between measurements I and IV. Percent muscle topography significantly decreased for the flexors and extensors of the shoulder and the

The Spin Torque Lego - from spin torque nano-devices to advanced computing architectures

Science.gov (United States)

Grollier, Julie

2013-03-01

Spin transfer torque (STT), predicted in 1996, and first observed around 2000, brought spintronic devices to the realm of active elements. A whole class of new devices, based on the combined effects of STT for writing and Giant Magneto-Resistance or Tunnel Magneto-Resistance for reading has emerged. The second generation of MRAMs, based on spin torque writing : the STT-RAM, is under industrial development and should be out on the market in three years. But spin torque devices are not limited to binary memories. We will rapidly present how the spin torque effect also allows to implement non-linear nano-oscillators, spin-wave emitters, controlled stochastic devices and microwave nano-detectors. What is extremely interesting is that all these functionalities can be obtained using the same materials, the exact same stack, simply by changing the device geometry and its bias conditions. So these different devices can be seen as Lego bricks, each brick with its own functionality. During this talk, I will show how spin torque can be engineered to build new bricks, such as the Spintronic Memristor, an artificial magnetic nano-synapse. I will then give hints on how to assemble these bricks in order to build novel types of computing architectures, with a special focus on neuromorphic circuits. Financial support by the European Research Council Starting Grant NanoBrain (ERC 2010 Stg 259068) is acknowledged.

Angular Acceleration without Torque?

Science.gov (United States)

Kaufman, Richard D.

2012-01-01

Hardly. Just as Robert Johns qualitatively describes angular acceleration by an internal force in his article "Acceleration Without Force?" here we will extend the discussion to consider angular acceleration by an internal torque. As we will see, this internal torque is due to an internal force acting at a distance from an instantaneous center.

Simbolismo e poder nas relações empresa-funcionário

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Fernanda Chiozzini Martins-Suarez

2016-06-01

Full Text Available A presente resenha convida o leitor a uma interpretação das relações de poder dentro de uma empresa siderúrgica, relações estas que são encontradas não apenas na dicotomia empresa-funcionário, mas também como resultado da inserção da mulher no mercado de trabalho. Entretanto, neste contexto, o peso da siderurgia se confunde com a leveza do símbolo significante construído pela empresa e representado pelo uniforme a fim de implantar na mente de seus funcionários a alegria e o prazer de trabalhar em uma companhia que tantas benesses trouxe aos seus funcionários e a cidade onde está instalada.

EMG-Torque Dynamics Change With Contraction Bandwidth.

Science.gov (United States)

Golkar, Mahsa A; Jalaleddini, Kian; Kearney, Robert E

2018-04-01

An accurate model for ElectroMyoGram (EMG)-torque dynamics has many uses. One of its applications which has gained high attention among researchers is its use, in estimating the muscle contraction level for the efficient control of prosthesis. In this paper, the dynamic relationship between the surface EMG and torque during isometric contractions at the human ankle was studied using system identification techniques. Subjects voluntarily modulated their ankle torque in dorsiflexion direction, by activating their tibialis anterior muscle, while tracking a pseudo-random binary sequence in a torque matching task. The effects of contraction bandwidth, described by torque spectrum, on EMG-torque dynamics were evaluated by varying the visual command switching time. Nonparametric impulse response functions (IRF) were estimated between the processed surface EMG and torque. It was demonstrated that: 1) at low contraction bandwidths, the identified IRFs had unphysiological anticipatory (i.e., non-causal) components, whose amplitude decreased as the contraction bandwidth increased. We hypothesized that this non-causal behavior arose, because the EMG input contained a component due to feedback from the output torque, i.e., it was recorded from within a closed-loop. Vision was not the feedback source since the non-causal behavior persisted when visual feedback was removed. Repeating the identification using a nonparametric closed-loop identification algorithm yielded causal IRFs at all bandwidths, supporting this hypothesis. 2) EMG-torque dynamics became faster and the bandwidth of system increased as contraction modulation rate increased. Thus, accurate prediction of torque from EMG signals must take into account the contraction bandwidth sensitivity of this system.

Valoración funcional del adulto mayor relacionado con el abandono familiar.

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Jenny Fernanda Villarroel Vargas

2017-03-01

Full Text Available Introducción: Se estima que entre el 2000 al 2050 la población mundial envejecida ascenderá del 11% al 22 %, con ello el incremento de las diversas enfermedades o trastornos propios de la edad. Objetivo: Establecer la relación entre capacidad funcional del adulto mayor con el abandono familiar en el barrio La Calera Centro, Latacunga, 2015-2016. Métodos: Se realizó un estudio observacional descriptivo de corte trasversal, donde previo consentimiento informado participaron 70 adultos mayores, a quienes se les aplicó escalas para valoración de la capacidad funcional, así como la encuesta para valorar abandono familiar y aspectos sociodemográficos de la población. Para el análisis estadístico se utilizó el test de Chi Cuadrado de Pearson con un nivel de significancia del 0,05. Resultados: Se reportó el abandono en el 75,7% de los adultos mayores y tuvo significancia con respecto a la capacidad funcional y la estructura familiar (p=0,002. Hubo relación  entre capacidad funcional y abandono familiar, así como también predominio de los adultos mayores entre los 65 a 74 años, sexo femenino, sin ninguna actividad laboral y analfabetos. Hubo relación significativa entre capacidad funcional, edades geriátricas y ocupación; y de igual manera entre la estructura familiar y el abandono. La capacidad funcional y la estructura familiar fueron factores asociados al abandono.    Conclusiones: La dependencia del adulto mayor condicionó a diferentes tipos de maltrato, destacando el abandono familiar.

Muscle response to pneumatic hand tool torque reaction forces.

Science.gov (United States)

Radwin, R G; VanBergeijk, E; Armstrong, T J

1989-06-01

Surface electromyography was used for studying the effects of torque reaction force acting against the hand, on forearm muscle activity and grip force for five subjects operating right angle, air shut-off nutrunners. Four tools having increasing spindle torque were operated using short and long torque reaction times. Nutrunner spindle torque ranged between 30 Nm and 100 Nm. Short torque reaction time was considered 0.5 s while long torque reaction time was 2 s. Peak horizontal force was the greatest component of the reaction force acting against the hand and accounted for more than 97% of the peak resultant hand force. Peak hand force increased from 89 N for the smallest tool to 202 N for the largest tool. Forearm muscle rms EMG, scaled for grip force, indicated average flexor activity during the Torque-reaction phase was more than four times greater than the Pre-start and Post Shut-off phases, and two times greater than the Run-down phase. Flexor EMG activity during the Torque-reaction phase increased for increasing tool peak spindle torque. Average flexor rms EMG activity, scaled for grip force, during the Torque-reaction phase increased from 372 N for the 30 Nm nutrunner to 449 N for the 100 Nm nutrunner. Flexor rms EMG activity averaged during the Torque-reaction phase and scaled for grip force was 390 N for long torque reaction times and increased to 440 N for short torque reaction times. Flexor rms EMG integrated over the torque reaction phase was 839 Ns for long torque reaction times and decreased to 312 Ns for short torque reaction times. The average latency between tool spindle torque onset and peak initial flexor rms EMG for long torque reaction times was 294 ms which decreased to 161 ms for short torque reaction times. The average latency between peak tool spindle torque, just prior to tool shut-off, and peak final rms EMG for long torque reaction times was 97 ms for flexors and 188 ms for extensors, which decreased for short torque reaction times to 47

O consumo de maconha na adolescência e as conseqüências nas funções cognitivas El consumo de marihuana en la adolescencia y sus consecuencias en las funciones The use of cannabis in adolescence and it's effects in the cognitive functions

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Maisa dos Santos Rigoni

2007-08-01

Full Text Available Este estudo objetiva comparar o desempenho nas funções cognitivas de 30 usuários de maconha e de 30 não usuários. Os instrumentos usados foram uma entrevista estruturada; Screening Cognitivo (WISC-III e WAIS-III; WCST e Figuras Complexas de Rey. A amostra foi de 60 adolescentes, idades entre 14 e 17 anos, e escolaridade mínima de 5ª série do Ensino Fundamental. Observou-se que houve diferença estatisticamente significativa no desempenho dos dois grupos em todos os testes neuropsicológicos aplicados; no subteste Código e no WCST, o grupo de usuários denotou desempenho mais prejudicado. Concluiu-se que a maconha pode afetar funções cognitivas de adolescentes usuários.Este estudio tiene como objetivo el de comparar el desempeño en las funciones cognitivas de 30 usuarios de marihuana y de 30 no usuarios. Los instrumentos usados fueron una entrevista estructurada; Screening Cognitivo (WISC-III y WAIS-III; WCST y Figuras Complejas de Rey. La muestra fue de 60 adolescentes, con edad entre 14 y 17 años y escolaridad mínima de 5 º año de la educación primaria. Se observó que hubo diferencia estadísticamente significativa en el desempeño de los dos grupos en todos los testes neuropsicológicos aplicados; en el sub-test código y no WCST, el grupo de usuarios obtuvo desempeño más perjudicado. Se concluyó que la marihuana puede afectar funciones cognitivas de adolescentes usuarios.The objective of the study was to compare the cognitive function performance between a group of 30 cannabis users and a group of 30 non-users. The instruments used were a structured interview; Cognitive Screening (WISC - III and WAIS-III; WCST and Rey Complex Figure Test. The sample was 60 adolescents, aged from 14 to 17 from 5th grade on. The results showed that was statistically significant difference in the performance of the two groups in every neuropsychological test applied, and, in the Digit Symbol and in the WCST subtests, the users' group showed

Correlação entre a dinamometria e teste funcional em atletas de handebol

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Fabiano Fernandes da Silva

2014-06-01

Full Text Available INTRODUÇÃO: São poucas as informações que relacionam testes funcionais com testes mais precisos, como a dinamometria isocinética. OBJETIVO: Correlacionar as variáveis isocinéticas pico de torque (PT, potência média (PM e trabalho total (TT de rotadores internos de ombro em atletas de handebol do gênero masculino com o teste funcional de arremesso de medicine ball (AMB. MÉTODOS: Participaram desse estudo 25 atletas amadores de handebol do gênero masculino com idade média 17,72 ± 2,16 anos. A coleta de dados foi realizada em dois dias diferentes, respeitando intervalo mínimo de 48 horas entre as sessões. De maneira aleatória, definida por sorteio, os atletas faziam o teste isocinético ou o teste de AMB. Para o teste de AMB, o atleta deveria arremessar uma medicine ball de 3 kg a maior distância possível. Para análise isocinética, foram utilizadas as velocidades de 60°/s e 180°/s avaliando a capacidade muscular dos músculos rotadores internos de ombro. Para análise de associações foram utilizados os testes de correlação de Pearson e regressão linear simples. RESULTADOS: Foram observadas associações moderadas (0,60 ≤ r < 0,70; p<0,05 para as variáveis PT, PM e TT e o teste de AMB na velocidade de 60°/s. Além disso, observaram-se associações altas (r ≥ 0,70; p<0,05 entre as variáveis estudadas na velocidade de 180°/s. CONCLUSÃO: As variáveis isocinéticas PT, PM e TT, de rotadores internos de ombro do braço dominante de atletas de handebol do gênero masculino apresentam correlação moderada a alta com o teste funcional de AMB.

Comparação entre idosos que sofreram quedas segundo desempenho físico e número de ocorrências Physical performance and number of falls in older adult fallers

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Grace A. O. Gomes

2009-10-01

Full Text Available OBJETIVOS: Analisar, entre idosos com ocorrência de quedas, a relação entre as variáveis sociodemográficas, clínicas, físicas e funcionais segundo as variáveis critério desempenho físico e número de quedas. MÉTODOS: Estudo transversal com 72 idosos (76,3±8,3 anos que sofreram quedas no último ano, sendo 65,3% mulheres, atendidos no ambulatório de geriatria de um hospital universitário de Campinas, SP. Os idosos foram divididos em grupo com pior (PDF e grupo com melhor desempenho físico (MDF, e em grupo com uma queda (1Q e grupo com duas quedas ou mais (2Q. As características sociodemográficas, clínicas, físicas e funcionais foram as variáveis independentes do estudo. Foi realizada análise de comparação entre os grupos. RESULTADOS: Os idosos do grupo PDF tiveram maior faixa etária, maior número de doenças e menor independência na maior parte das tarefas da dimensão motora em relação ao grupo MDF. Os idosos do grupo 2Q apresentaram maior número de doenças, menor força de preensão manual e menor independência na tarefa "controle das fezes" na dimensão motora da medida de independência funcional (MIF em relação ao grupo 1Q. CONCLUSÕES: Entre idosos que já caíram, piores níveis de desempenho físico relacionam-se com maior faixa etária, mais doenças e menos independência funcional. Além disso, ter sofrido quedas recorrentes relaciona-se com mais doenças, menos força muscular e menos independência funcional na tarefa de controle de fezes.OBJECTIVES: The aim of this study was to determine the relationship between sociodemographic, clinical, physical and functional data according to physical performance and number of falls among older fallers. METHODS: Cross-sectional study carried out among 72 older adults (76.3 ±8.3 years with a history of falls in the past year, 65.3% of which were women. The participants received care at the geriatric outpatient clinic of a university hospital in Campinas, SP

DAS FERRAMENTAS AOS COLABORADORES: a avaliação individual de desempenho em um dos maiores grupos de inspeção veicular do Brasil

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Victor Ribeiro Martins

2016-12-01

Full Text Available A máxima “de aquilo que não se mede não se conhece, não se controle e não melhora” nunca foi tão aplicável como no cenário competitivo atual. O processo de avaliação de desempenho nas organizações visa justamente avaliar o quão bem desenvolvidos são os colaboradores. A investigação e o mapeamento do processo de AD se dão em um dos maiores grupos de organismos de inspeção veicular do país, sediado na cidade de Cuiabá, Mato Grosso. Para isso, ao longo do desenvolvimento, descreve-se a estrutura interna da empresa e são propostas oportunidades para ajustes no modelo atual de avaliação. Os dados foram coletados por meio de entrevista com roteiro semiestruturado cujas questões visavam captar a percepção dos mesmos sobre o processo de AD. Sugere-se, com base nos resultados, o desenvolvimento de um método de AD mais eficiente, em direção ao modelo de Avaliação 360º. Ao fim do estudo, foi possível inferir o quão necessário é a Avaliação de Desempenho para o desenvolvimento do colaborador e por isso propôs-se que a empresa a tome como constante, com o objetivo de incentivar os funcionários a buscarem um constante desenvolvimento profissional.

A non-unity torque sharing function for torque ripple minimization of switched reluctance generators

DEFF Research Database (Denmark)

Park, Kiwoo; Liu, Xiao; Chen, Zhe

2013-01-01

This paper presents a new torque ripple minimization technique for a Switched Reluctance Generator (SRG). Although the SRG has many advantageous characteristics as a generator, it has not been widely employed in the industry. One of the most notorious disadvantages of the SRG is its high torque...

TESTE DE CAMINHADA DE SEIS MINUTOS: DESEMPENHO DE CRIANÇAS COM EXCESSO DE PESO

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Fabíola Unbehaun Cibinello

Full Text Available RESUMO Introdução: O teste de caminhada de seis minutos (TC6' tem sido utilizado para avaliar a capacidade funcional do exercício em crianças. Objetivo: Comparar o desempenho no teste de caminhada de seis minutos em escolares na faixa etária entre 8 a 10 anos, conforme a classificação nutricional, com base em dois diferentes critérios. Métodos: A amostra de 226 crianças entre 8 a 10 anos foi dividida em três grupos (eutrófico, sobrepeso e obeso, de acordo com os critérios de classificação nutricional propostos pela Organização Mundial da Saúde (OMS e pela International Obesity Task Force (IOTF e avaliada por meio do teste de caminhada de seis minutos. Resultados: A prevalência de sobrepeso e obesidade na amostra foi de 42,48% de acordo com o critério da OMS e 38,94% pelo critério da IOTF. Não ocorreram diferenças estatisticamente significantes entre os grupos eutrófico, sobrepeso e obeso, quando os resultados do TC6' foram comparados, tanto na distância percorrida quanto no percentual do predito para a criança, de acordo com os valores de referência, e também de acordo com os dois critérios de classificação nutricional. A frequência cardíaca final do teste foi estatisticamente maior nos grupos sobrepeso e obeso, tanto pelo critério OMS (p = 0,0015, quanto pelo critério IOTF (p = 0,0160 . Conclusões: Na amostra estudada não houve diferença no desempenho do TC6' entre crianças eutróficas, com sobrepeso e obesas. Porém, a frequência cardíaca final do teste foi significantemente maior entre as crianças com excesso de peso. Os resultados ressaltam que medidas de prevenção, acompanhamento e tratamento são necessárias, promovendo hábitos saudáveis.

A lateralidade cruzada e o desempenho da leitura e escrita em escolares

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Francisco Rosa Neto

2013-08-01

Full Text Available OBJETIVO: analisar o desempenho da leitura e escrita em escolares com lateralidade cruzada. MÉTODO: fizeram parte da amostra 166 escolares do terceiro ano do ensino fundamental, com idade entre oito e nove anos. Para avaliação da lateralidade, foi utilizada a escala de desenvolvimento motor -EDM, e para a analise da leitura e escrita foi utilizado o Manual de Desempenho Escolar - MDE. Na análise comparativa do desempenho da leitura e escrita em função da lateralidade (Cruzada, a amostra foi dividida em 2 grupos. Para análise e interpretação dos dados foram utilizados os programas Excel e SPSS for Windows 17.0 e para a análise comparativa entre os dois grupos, o teste "t" para amostras independentes quando os dados se mostraram simétricos, e o teste Mann-Whitney para os dados assimétricos, e para a distribuição dos dados, o teste Shapiro-Wilk. O nível de significância adotado nesse estudo foi p< 0,05. RESULTADOS: verificou- se que de todas as variáveis do desempenho da leitura e da escrita, foram maiores para o grupo das crianças com dominância lateral completa do que para o grupo das crianças com lateralidade cruzada. Na escrita, houve diferença significante entre os dois grupos, sendo atribuído melhor desempenho às crianças com lateralidade destro-completa. CONCLUSÃO: evidencia-se que as crianças com lateralidade cruzada apresentam desempenho inferior na leitura e escrita quando comparadas às crianças com dominância lateral completa. Estes dados justificam a relevância do desenvolvimento psicomotor na infância como fator essencial no processo de aprendizagem escolar.

Funciones sociales del folclore

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Alberto Londoño Álvarez

1969-07-01

Full Text Available Con el objeto de estudiar los principales aspectos sociológicos del folclore, empecemos con uno de los problemas más significativos, cual es el análisis de sus funciones que cumple en una sociedad. se trata de un asunto perteneciente al sociólogo, quien, con el propósito de mostrar al folclórogo, que su investigación no es única, porque se refiere a un hecho que pertenece al grupo de los fenómenos sociales.

Envelhecimento ativo e sua relação com a independência funcional

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Olívia Galvão Lucena Ferreira

2012-01-01

Full Text Available El objetivo del presente estudio fue analizar los factores determinantes del envejecimiento activo y su relación con la independencia funcional. La investigación se realizó con 100 personas mayores de una Unidad de Salud de la Familia, en João Pessoa-PB, Brasil. Como instrumentos para la evaluación de personas mayores se utilizó la Medida de Independencia Funcional y un cuestionario sociodemográfico. Los datos fueron analizados a través del software SPSS. Según los resultados, todos los sujetos presentan la independencia funcional para llevar a cabo las actividades analizadas. Los datos también demostraron que la independencia funcional promueve una mayor integración de las personas mayores en la comunidad, mediante el fortalecimiento de los lazos sociales y familiares, de amistad y de ocio, y esos factores se consideran como determinantes del envejecimiento activo.

Una aplicación de las funciones débilmente contractivas a problemas de valor en la frontera de funciones con valores en intervalos

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Vladimir Angulo-Castillo

2014-06-01

Full Text Available Se estudia la existencia y unicidad de soluciones para problemas de valor en la frontera asociadas a ecuaciones diferenciales de funciones con valores en intervalos, usando la derivada de Hukuhara y algunos teoremas de punto fijo de funciones débilmente contractivas definidas en conjuntos parcialmente ordenados. Abstract. We study the existence and uniqueness of solutions for boundary value problems associated to differential equations of interval-valued functions, by using the derivative of Hukuhara and some fixed point theorems for weakly contractive mappings defined on partially ordered sets.

Enhanced precision of ankle torque measure with an open-unit dynamometer mounted with a 3D force-torque sensor.

Science.gov (United States)

Toumi, A; Leteneur, S; Gillet, C; Debril, J-F; Decoufour, N; Barbier, F; Jakobi, J M; Simoneau-Buessinger, Emilie

2015-11-01

Many studies have focused on maximum torque exerted by ankle joint muscles during plantar flexion. While strength parameters are typically measured with isokinetic or isolated ankle dynamometers, these devices often present substantial limitations for the measurement of torque because they account for force in only 1 dimension (1D), and the device often constrains the body in a position that augments torque through counter movements. The purposes of this study were to determine the contribution of body position to ankle plantar-flexion torque and to assess the use of 1D and 3D torque sensors. A custom designed 'Booted, Open-Unit, Three dimension, Transportable, Ergometer' (B.O.T.T.E.) was used to quantify plantar flexion in two conditions: (1) when the participant was restrained within the unit (locked-unit) and (2) when the participant's position was independent of the ankle dynamometer (open-unit). Ten young males performed maximal voluntary isometric plantar-flexion contractions using the B.O.T.T.E. in open and locked-unit mechanical configurations. The B.O.T.T.E. was reliable with ICC higher than 0.90, and CV lower than 7 %. The plantar-flexion maximal resultant torque was significantly higher in the locked-unit compared with open-unit configuration (P torque sensor significantly underestimated the proper capacity of plantar-flexion torque production (P torque should be performed with an open-unit dynamometer mounted with a 3D sensor that is exclusive of accessory muscles but inclusive of all ankle joint movements.

Technology on precision measurement of torque and force

International Nuclear Information System (INIS)

2005-12-01

This book gives a descriptions on force standards system about movement of object, direction and structure. Next, it deals with torque standards, torque measuring instrument and torque wrench with how to use, explanations, unit and test. This book written by Korea Association of standards and testing organizations is for exact measurement and test of force and torque.

Loss of knee extensor torque complexity during fatiguing isometric muscle contractions occurs exclusively above the critical torque.

Science.gov (United States)

Pethick, Jamie; Winter, Samantha L; Burnley, Mark

2016-06-01

The complexity of knee extensor torque time series decreases during fatiguing isometric muscle contractions. We hypothesized that because of peripheral fatigue, this loss of torque complexity would occur exclusively during contractions above the critical torque (CT). Nine healthy participants performed isometric knee extension exercise (6 s of contraction, 4 s of rest) on six occasions for 30 min or to task failure, whichever occurred sooner. Four trials were performed above CT (trials S1-S4, S1 being the lowest intensity), and two were performed below CT (at 50% and 90% of CT). Global, central, and peripheral fatigue were quantified using maximal voluntary contractions (MVCs) with femoral nerve stimulation. The complexity of torque output was determined using approximate entropy (ApEn) and the detrended fluctuation analysis-α scaling exponent (DFA-α). The MVC torque was reduced in trials below CT [by 19 ± 4% (means ± SE) in 90%CT], but complexity did not decrease [ApEn for 90%CT: from 0.82 ± 0.03 to 0.75 ± 0.06, 95% paired-samples confidence intervals (CIs), 95% CI = -0.23, 0.10; DFA-α from 1.36 ± 0.01 to 1.32 ± 0.03, 95% CI -0.12, 0.04]. Above CT, substantial reductions in MVC torque occurred (of 49 ± 8% in S1), and torque complexity was reduced (ApEn for S1: from 0.67 ± 0.06 to 0.14 ± 0.01, 95% CI = -0.72, -0.33; DFA-α from 1.38 ± 0.03 to 1.58 ± 0.01, 95% CI 0.12, 0.29). Thus, in these experiments, the fatigue-induced loss of torque complexity occurred exclusively during contractions performed above the CT. Copyright © 2016 the American Physiological Society.

Arquitectura, arte funcional

Directory of Open Access Journals (Sweden)

Monjo Carrió, Juan

1985-10-01

Full Text Available The begining of this work is devoted to the analysis of the concepts of Art, Science and Technique and their historical evolution, distinguishing between "fine arts" and "technique arts". Following, Architect and Architecture terms are defined both conceptual and professionally, analysing as well its historical evolution and pointing out the interdependence between the architectural conception as "fine art" and the constructive technology as "technique art", finally reminding the necessary scientific base of this one (Construction Physics. Consequently, the need for architecture professionals of constructive technology knowledge, is also reminded. At last, the functional character of the Architecture (Architecture as a "functional art" is analysed, going over the three basic aspects of this functionality (Integrity-firmitas, Habitability-utilitas and Aesthetics-venustas.Se inicia el trabajo analizando los conceptos de Arte, Ciencia y Técnica y su evolución histórica, distinguiendo entre ¡as "bellas artes" y las "artes técnicas". A continuación se definen los conceptos de Arquitecto y Arquitectura, tanto conceptual como profesionalmente, analizando, asimismo, su evolución histórica y haciendo hincapié en la interdependencia entre la concepción arquitectónica como "bella arte" y la tecnología constructiva como "arte técnica", para terminar recordando la necesaria base científica de esta última (la Física de la Construcción. Como consecuencia, se recuerda la necesidad de los conocimientos de la tecnología constructiva en los arquitectos profesionales. Por último, se analiza el carácter funcional de la Arquitectura (Arquitectura como "arte funcional" y se hace un breve recorrido por los tres aspectos básicos de esa funcionalidad (Integridad-firmitas, Habitabilidad-utilitas y Estética-venustas.

Capacidade funcional, morbidades e qualidade de vida de idosos

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Darlene Mara dos Santos Tavares

2012-01-01

Full Text Available La investigación tiene como objetivo describir el perfil demográfico, la capacidad funcional y la morbilidad de los ancianos, y verificar la calidad de vida relacionado con el número de incapacidad funcional y la morbilidad. Estudio transversal analítico llevado a cabo con 2.142 personas mayores. Los datos fueron recolectados en el hogar con un instrumento estructurado. El análisis se realizó distribución de frecuencias, F-test de ANOVA y Bonferroni (p<0,05. La mayoría eran mujeres, años, casado, años de escolaridad y los ingresos de un salario mínimo. Predominaron los adultos mayores discapacidades funcionales relacionadas con la movilidad y morbilidad, los problemas de visión más frecuente y la columna vertebral y la hipertensión. Las puntuaciones más altas de calidad de vida para las relaciones sociales y el funcionamiento de los sentidos y el más bajo para su desarrollo físico y la autonomía. El mayor número de incapacidad funcional y la morbilidad asociadas con bajas puntuaciones en la calidad de vida.

Computerized Torque Control for Large dc Motors

Science.gov (United States)

Willett, Richard M.; Carroll, Michael J.; Geiger, Ronald V.

1987-01-01

Speed and torque ranges in generator mode extended. System of shunt resistors, electronic switches, and pulse-width modulation controls torque exerted by large, three-phase, electronically commutated dc motor. Particularly useful for motor operating in generator mode because it extends operating range to low torque and high speed.

Hybrid synchronous motor electromagnetic torque research

Directory of Open Access Journals (Sweden)

Suvorkova Elena E.

2014-01-01

Full Text Available Electromagnetic field distribution models in reluctance and permanent magnet parts were made by means of Elcut. Dependences of electromagnetic torque on torque angle were obtained.

Special-Purpose High-Torque Permanent-Magnet Motors

Science.gov (United States)

Doane, George B., III

1995-01-01

Permanent-magnet brushless motors that must provide high commanded torques and satisfy unusual heat-removal requirement are developed. Intended for use as thrust-vector-control actuators in large rocket engines. Techniques and concepts used to design improved motors for special terrestrial applications. Conceptual motor design calls for use of rotor containing latest high-energy-product rare-earth permanent magnets so that motor produces required torque while drawing smallest possible currents from power supply. Torque generated by electromagnetic interaction between stator and permanent magnets in rotor when associated electronic circuits applied appropriately temporally and spatially phased currents to stator windings. Phase relationships needed to produce commanded torque computed in response to torque command and to electronically sensed angular position of rotor relative to stator.

Heat-driven spin torques in antiferromagnets

Science.gov (United States)

Białek, Marcin; Bréchet, Sylvain; Ansermet, Jean-Philippe

2018-04-01

Heat-driven magnetization damping, which is a linear function of a temperature gradient, is predicted in antiferromagnets by considering the sublattice dynamics subjected to a heat-driven spin torque. This points to the possibility of achieving spin torque oscillator behavior. The model is based on the magnetic Seebeck effect acting on sublattices which are exchange coupled. The heat-driven spin torque is estimated and the feasibility of detecting this effect is discussed.

Tailoring spin-orbit torque in diluted magnetic semiconductors

KAUST Repository

Li, Hang; Wang, Xuhui; Doǧan, Fatih; Manchon, Aurelien

2013-01-01

We study the spin orbit torque arising from an intrinsic linear Dresselhaus spin-orbit coupling in a single layer III-V diluted magnetic semiconductor. We investigate the transport properties and spin torque using the linear response theory, and we report here: (1) a strong correlation exists between the angular dependence of the torque and the anisotropy of the Fermi surface; (2) the spin orbit torque depends nonlinearly on the exchange coupling. Our findings suggest the possibility to tailor the spin orbit torque magnitude and angular dependence by structural design.

Tailoring spin-orbit torque in diluted magnetic semiconductors

KAUST Repository

Li, Hang

2013-05-16

We study the spin orbit torque arising from an intrinsic linear Dresselhaus spin-orbit coupling in a single layer III-V diluted magnetic semiconductor. We investigate the transport properties and spin torque using the linear response theory, and we report here: (1) a strong correlation exists between the angular dependence of the torque and the anisotropy of the Fermi surface; (2) the spin orbit torque depends nonlinearly on the exchange coupling. Our findings suggest the possibility to tailor the spin orbit torque magnitude and angular dependence by structural design.

Funciones ejecutivas y Rendimiento Escolar en Educación Primaria

OpenAIRE

Caro-Franco, Federico

2016-01-01

En el presente Trabajo de Fin de Máster se ha investigado si existe vinculación entre el rendimiento escolar y las funciones ejecutivas en los alumnos que cursan Educación Primaria. Para ello, se evaluaron 32 alumnos de entre 6 y 8 años, 16 de los cuales presentaban un rendimiento académico bajo, y los restantes 16, un rendimiento académico normalizado. Para diagnosticar el grado de rendimiento de las funciones ejecutivas, se evaluó la atención, tanto sostenida como selectiva, la planificació...

Entrenamiento Cognitivo de las Funciones Ejecutivas en la Edad Escolar

OpenAIRE

María Luisa Betancur-Caro; David A. Molina; Lilian Yohana Cañizales-Romaña

2016-01-01

En este artículo nuestro objetivo es evaluar y analizar el Rendimiento Académico de un niño en edad escolar a partir de un programa de entrenamiento cognitivo de las Funciones Ejecutivas. Realizamos el estudio de caso en tres momentos: evaluación inicial pretest con subpruebas de la Banfe y la ENI; identificamos el estado de las funciones ejecutivas, el entrenamiento cognitivo del Control Inhibitorio, la Fluidez y la Planeación, y la evaluación final postest con el mismo repertorio de la eval...

Influence of Closed Stator Slots on Cogging Torque

DEFF Research Database (Denmark)

Ion, Trifu; Leban, Krisztina Monika; Ritchie, Ewen

2013-01-01

Cogging torque results due interaction of magnetic field of magnets and stator slots, and have negative effects on permanent magnet machines such as vibrations, noise, torque ripples and problems during turbine start-up and cut-in. In order to reduce cogging torque this paper presents a study...... of influence of closed stator slots on cogging torque using magnetic slot wedges....

Dietas pós-eclosão suplementadas com fontes de gordura e acrescidas de taurina e glicina sobre a morfometria intestinal e o desempenho de frangos de corte de um a 21 dias

Directory of Open Access Journals (Sweden)

J.I.M. Fernandes

Full Text Available RESUMO O objetivo deste estudo foi avaliar o efeito do fornecimento de dietas pós-eclosão suplementadas com diferentes fontes de gordura insaturada e adicionadas ou não de taurina e glicina sobre o desempenho produtivo, a biometria e a morfometria do intestino delgado de pintos de corte de um a 21 dias de idade. Foram utilizados 480 pintos de corte machos de um dia de idade da linhagem Cobb. O delineamento foi inteiramente ao acaso, em esquema fatorial 2 x 4, com e sem suplementação de taurina e glicina e quatro dietas (controle, óleo de peixe, de soja e de girassol, totalizando oito tratamentos com seis repetições de 10 aves cada. As rações experimentais foram fornecidas de zero a quatro dias de idade. O desempenho zootécnico foi avaliado ao alojamento e aos quatro, sete e 21 dias de idade. Nestas mesmas datas, foram sacrificadas duas aves por unidade experimental para biometria do intestino e histomorfometria da mucosa do intestino. A adição de diferentes fontes de gordura e a suplementação de glicina e taurina às dietas de transição não influenciaram o desempenho produtivo de um a 21 dias. A suplementação das dietas com glicina e taurina alterou a morfologia da mucosa intestinal, principalmente do duodeno, resultando em maior comprimento do vilo e relação vilo:cripta. Entretanto, parte dos efeitos positivos depende do tipo de óleo adicionado, mostrando que dietas pós-eclosão acrescidas de fontes de lipídios podem ser benéficas no desenvolvimento da capacidade funcional do intestino de frangos de corte.

Impression management e o desempenho organizacional: o caso português

OpenAIRE

Borges, Maria de Fátima Ribeiro

2011-01-01

O estudo pretende avaliar o impacte do desempenho organizacional na adopção de estratégias de impression management. O estudo apresenta uma análise de conteúdo de 45 cartas do Presidente do Conselho de Administração, contidas nos relatórios e contas anuais de 2010, das empresas Portuguesas não financeiras. Os resultados indicam que o desempenho organizacional não influencia a adoção de estratégias de impression management. Consistente com a teoria psicológica social de im...

Electrostatic sensor modeling for torque measurements

Science.gov (United States)

Mika, Michał; Dannert, Mirjam; Mett, Felix; Weber, Harry; Mathis, Wolfgang; Nackenhorst, Udo

2017-09-01

Torque load measurements play an important part in various engineering applications, as for automotive industry, in which the drive torque of a motor has to be determined. A widely used measuring method are strain gauges. A thin flexible foil, which supports a metallic pattern, is glued to the surface of the object the torque is being applied to. In case of a deformation due to the torque load, the change in the electrical resistance is measured. With the combination of constitutive equations the applied torque load is determined by the change of electrical resistance. The creep of the glue and the foil material, together with the temperature and humidity dependence, may become an obstacle for some applications Kapralov and Fesenko (1984). Thus, there have been optical and magnetical, as well as capacitive sensors introduced). This paper discusses the general idea behind an electrostatic capacitive sensor based on a simple draft of an exemplary measurement setup. For better understanding an own electrostatical, geometrical and mechanical model of this setup has been developed.

Electrostatic sensor modeling for torque measurements

Directory of Open Access Journals (Sweden)

M. Mika

2017-09-01

Full Text Available Torque load measurements play an important part in various engineering applications, as for automotive industry, in which the drive torque of a motor has to be determined. A widely used measuring method are strain gauges. A thin flexible foil, which supports a metallic pattern, is glued to the surface of the object the torque is being applied to. In case of a deformation due to the torque load, the change in the electrical resistance is measured. With the combination of constitutive equations the applied torque load is determined by the change of electrical resistance. The creep of the glue and the foil material, together with the temperature and humidity dependence, may become an obstacle for some applications Kapralov and Fesenko(1984. Thus, there have been optical and magnetical, as well as capacitive sensors introduced . This paper discusses the general idea behind an electrostatic capacitive sensor based on a simple draft of an exemplary measurement setup. For better understanding an own electrostatical, geometrical and mechanical model of this setup has been developed.

Accuracy of mechanical torque-limiting devices for dental implants.

Science.gov (United States)

L'Homme-Langlois, Emilie; Yilmaz, Burak; Chien, Hua-Hong; McGlumphy, Edwin

2015-10-01

A common complication in implant dentistry is unintentional implant screw loosening. The critical factor in the prevention of screw loosening is the delivery of the appropriate target torque value. Mechanical torque-limiting devices (MTLDs) are the most frequently recommended devices by the implant manufacturers to deliver the target torque value to the screw. Two types of MTLDs are available: friction-style and spring-style. Limited information is available regarding the influence of device type on the accuracy of MTLDs. The purpose of this study was to determine and compare the accuracy of spring-style and friction-style MTLDs. Five MTLDs from 6 different dental implant manufacturers (Astra Tech/Dentsply, Zimmer Dental, Biohorizons, Biomet 3i, Straumann [ITI], and Nobel Biocare) (n=5 per manufacturer) were selected to determine their accuracy in delivering target torque values preset by their manufacturers. All torque-limiting devices were new and there were 3 manufacturers for the friction-style and 3 manufacturers for the spring-style. The procedure of target torque measurement was performed 10 times for each device and a digital torque gauge (Chatillon Model DFS2-R-ND; Ametek) was used to record the measurements. Statistical analysis used nonparametric tests to determine the accuracy of the MTLDs in delivering target torque values and Bonferroni post hoc tests were used to assess pairwise comparisons. Median absolute difference between delivered torque values and target torque values of friction-style and spring-style MTLDs were not significantly different (P>.05). Accuracy of Astra Tech and Zimmer Dental friction-style torque-limiting devices were significantly different than Biohorizons torque-limiting devices (Ptorque value. Astra Tech and Zimmer Dental friction-style torque-limiting devices were significantly more accurate than Biohorizons (C) torque-limiting devices (Ptorque-limiting devices fell within ±10% of the target torque value preset by the

Integral torque balance in tokamaks

International Nuclear Information System (INIS)

Pustovitov, V.D.

2011-01-01

The study is aimed at clarifying the balance between the sinks and sources in the problem of intrinsic plasma rotation in tokamaks reviewed recently by deGrassie (2009 Plasma Phys. Control. Fusion 51 124047). The integral torque on the toroidal plasma is calculated analytically using the most general magnetohydrodynamic (MHD) plasma model taking account of plasma anisotropy and viscosity. The contributions due to several mechanisms are separated and compared. It is shown that some of them, though, possibly, important in establishing the rotation velocity profile in the plasma, may give small input into the integral torque, but an important contribution can come from the magnetic field breaking the axial symmetry of the configuration. In tokamaks, this can be the error field, the toroidal field ripple or the magnetic perturbation created by the correction coils in the dedicated experiments. The estimates for the error-field-induced electromagnetic torque show that the amplitude of this torque is comparable to the typical values of torques introduced into the plasma by neutral beam injection. The obtained relations allow us to quantify the effect that can be produced by the existing correction coils in tokamaks on the plasma rotation, which can be used in experiments to study the origin and physics of intrinsic rotation in tokamaks. Several problems are proposed for theoretical studies and experimental tests.

TORQUE MEASUREMENT IN WORM AGLOMERATION MACHINE

Directory of Open Access Journals (Sweden)

Marian DUDZIAK

2014-03-01

Full Text Available The paper presents the operating characteristics of the worm agglomeration machine. The paper indicates the need for continuous monitoring of the value of the torque due to the efficiency of the machine. An original structure of torque meter which is built in the standard drive system of briquetting machine was presented. A number of benefits arising from the application of the proposed solution were presented. Exemplary measurement results obtained by means of this torque meter were presented.

A CAPACIDADE INOVATIVA E O DESEMPENHO ECONÔMICO-FINANCEIRO DE EMPRESAS INOVADORAS BRASILEIRAS

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Kléber Formiga Miranda

Full Text Available RESUMOCom base nos pressupostos teóricos da Visão Baseada em Recursos (VBR, considerando a utilização de recursos disponíveis internamente nas organizações para manutenção de sua vantagem competitiva por meio da diferenciação, a pesquisa analisa a relação entre a capacidade inovativa e o desempenho econômico-financeiro de empresas brasileiras. A amostra foi extraída a partir das empresas listadas na BM&FBovespa consideradas inovadoras, segundo o IBI. As variáveis de capacidade inovativa coletadas a partir das PINTECs 2005 e 2008 e de desempenho através do Economática(r foram tratadas por meio de análises de correlação e de regressão. Os resultados indicam que os desempenhos econômico (ROA e operacional (EBITDA/Ativo Total não são significativamente influenciados pela capacidade inovativa. No entanto, quando se separa a capacidade inovativa por seus componentes (inovação de produto, processo, organizacional e marketing, observa-se uma influência positiva de inovação de produto sobre ambos os desempenhos. Por sua vez, o desempenho de valor (MVA é influenciado positiva e significativamente pela capacidade inovativa. Esses resultados sugerem melhores resultados contábeis quando as empresas inovam no produto e maior geração de valor pelo mercado ao possuir um portfólio diversificado de inovação, ou seja, maior capacidade inovativa. Não se pode, entretanto, negligenciar as inovações em processo, organizacional emarketing. A pouca relação dessas inovações, perceptíveis no âmbito interno da empresa, com o desempenho pode residir nas diferentes estratégias inovativas adotadas em prol do objetivo principal de cada empresa.

Improvements in remote equipment torquing and fastening

International Nuclear Information System (INIS)

Garin, J.

1978-01-01

Remote torquing and fastening is a requirement of generic interest for application in an environment not readily accessible to man. The developments over the last 30 years in torque-controlled equipment above 200 nm (150 ft/lb) have not been emphasized. The development of specialized subassemblies to torque and fasten equipment in a remotely controlled environment is an integral part of the Advanced Fuel Recycle Program at Oak Ridge National Laboratory. Commercially available subassemblies have been adapted into a system that would provide remote torquing and fastening in the range of 200 to 750 nm (150 to 550 ft/lb). 9 figures

A Moderação-Mediada do Sistema de Controle na Ambidestria

Directory of Open Access Journals (Sweden)

Valter da Silva Faia

2017-12-01

Full Text Available As demandas solicitadas pelos clientes conduzem os funcionários da linha de frente a buscar objetivos simultâneos que competem entre si por recursos. Funcionários que demonstram a capacidade de atender objetivos simultâneos são denominados ambidestros e são favorecidos quando há fatores organizacionais que os permitem e os encorajam a fazer seu próprio julgamento sobre como aplicar os recursos na conquista dos objetivos. Neste trabalho, ampliamos a discussão da ambidestria do nível organizacional para o nível individual e propomos que a ambidestria provisão de serviços e cross-/up-selling apresenta um efeito condicional ao explicar o desempenho. Especificamente, este efeito condicional significa que a ambidestria é mediadora do efeito da locomoção no desempenho, sendo esse efeito indireto moderado pelo sistema de controle de vendas. Fizemos uma pesquisa descritiva do tipo survey com 118 funcionários de laboratórios. Os achados mostraram que a orientação para locomoção se relaciona positivamente com o comportamento ambidestro do indivíduo; que a presença de um sistema de controle por resultado modera a relação locomoção-ambidestria, amplificando-a; e que essa relação moderada foi mediada pela ambidestria, quando explicando o desempenho.

Temperature dependence of spin-orbit torques in Cu-Au alloys

KAUST Repository

Wen, Yan; Wu, Jun; Li, Peng; Zhang, Qiang; Zhao, Yuelei; Manchon, Aurelien; Xiao, John Q.; Zhang, Xixiang

2017-01-01

We investigated current driven spin-orbit torques in Cu40Au60/Ni80Fe20/Ti layered structures with in-plane magnetization. We have demonstrated a reliable and convenient method to separate dampinglike torque and fieldlike torque by using the second harmonic technique. It is found that the dampinglike torque and fieldlike torque depend on temperature very differently. Dampinglike torque increases with temperature, while fieldlike torque decreases with temperature, which are different from results obtained previously in other material systems. We observed a nearly linear dependence between the spin Hall angle and longitudinal resistivity, suggesting that skew scattering may be the dominant mechanism of spin-orbit torques.

Temperature dependence of spin-orbit torques in Cu-Au alloys

KAUST Repository

Wen, Yan

2017-03-07

We investigated current driven spin-orbit torques in Cu40Au60/Ni80Fe20/Ti layered structures with in-plane magnetization. We have demonstrated a reliable and convenient method to separate dampinglike torque and fieldlike torque by using the second harmonic technique. It is found that the dampinglike torque and fieldlike torque depend on temperature very differently. Dampinglike torque increases with temperature, while fieldlike torque decreases with temperature, which are different from results obtained previously in other material systems. We observed a nearly linear dependence between the spin Hall angle and longitudinal resistivity, suggesting that skew scattering may be the dominant mechanism of spin-orbit torques.

Spin-torque generation in topological insulator based heterostructures

KAUST Repository

Fischer, Mark H.

2016-03-11

Heterostructures utilizing topological insulators exhibit a remarkable spin-torque efficiency. However, the exact origin of the strong torque, in particular whether it stems from the spin-momentum locking of the topological surface states or rather from spin-Hall physics of the topological-insulator bulk, remains unclear. Here, we explore a mechanism of spin-torque generation purely based on the topological surface states. We consider topological-insulator-based bilayers involving ferromagnetic metal (TI/FM) and magnetically doped topological insulators (TI/mdTI), respectively. By ascribing the key theoretical differences between the two setups to location and number of active surface states, we describe both setups within the same framework of spin diffusion of the nonequilibrium spin density of the topological surface states. For the TI/FM bilayer, we find large spin-torque efficiencies of roughly equal magnitude for both in-plane and out-of-plane spin torques. For the TI/mdTI bilayer, we elucidate the dominance of the spin-transfer-like torque. However, we cannot explain the orders of magnitude enhancement reported. Nevertheless, our model gives an intuitive picture of spin-torque generation in topological-insulator-based bilayers and provides theoretical constraints on spin-torque generation due to topological surface states.

Desempenho de motor diesel quatro tempos alimentado com biodiesel de óleo de soja (B 100 Performance of four stroke diesel cycle engine supplied with soybean oil biodiesel (B 100

Directory of Open Access Journals (Sweden)

Carlos Eduardo Silva Volpato

2009-08-01

Full Text Available Objetivou-se, neste trabalho, avaliar o desempenho de um motor de ciclo diesel quatro tempos e quatro cilindros utilizando biodiesel de óleo de soja (B100, em comparação ao óleo diesel. Foram analisados os parâmetros: potência efetiva e reduzida, torque, consumo específico e energético de combustível, eficiência termomecânica e volumétrica. Foi instalado um ensaio com delineamento inteiramente casualizado (DIC em esquema fatorial, realizada análise de variância e aplicado teste de Tukey, a 5%. Foram pesquisados cinco níveis de rotação em quatro repetições (650, 570, 490, 410, 320 e 240 rpm. O motor alimentado com biodiesel apresentou torque e potência reduzida um pouco menor que quando alimentado com óleo diesel fóssil, entretanto, os consumos especifico e horário, apresentaram resultados mais satisfatórios que o diesel fóssil.The aim of this work was to compare the performance of a four stroke diesel cycle engine and a four cylinder using biodiesel made from soy oil (B100, in comparison with the diesel oil. The parameters analyzed were: effective power and reduced power, torque, specific and energetic consumption of fuel, thermal-mechanics and volumetric efficiency. An entirely randomized experiment design was installed (DIC in a factorial structure, the analysis of variance was carried out and the Tukey test was applied at the level of 5%. Five rotation levels were researched in four replications (650, 570, 490, 410, 320, and 240 rpm. The engine fed with biodiesel presented torque and reduced power a little lower than the engine fed with fossil diesel. However, specific and hourly consumptions presented more satisfactory results.

Current-induced torques and interfacial spin-orbit coupling

KAUST Repository

Haney, Paul M.; Lee, Hyun-Woo; Lee, Kyung-Jin; Manchon, Aurelien; Stiles, M. D.

2013-01-01

In bilayer systems consisting of an ultrathin ferromagnetic layer adjacent to a metal with strong spin-orbit coupling, an applied in-plane current induces torques on the magnetization. The torques that arise from spin-orbit coupling are of particular interest. Here we use first-principles methods to calculate the current-induced torque in a Pt-Co bilayer to help determine the underlying mechanism. We focus exclusively on the analog to the Rashba torque, and do not consider the spin Hall effect. The details of the torque depend strongly on the layer thicknesses and the interface structure, providing an explanation for the wide variation in results found by different groups. The torque depends on the magnetization direction in a way similar to that found for a simple Rashba model. Artificially turning off the exchange spin splitting and separately the spin-orbit coupling potential in the Pt shows that the primary source of the “fieldlike” torque is a proximate spin-orbit effect on the Co layer induced by the strong spin-orbit coupling in the Pt.

Detecting Casimir torque with an optically levitated nanorod

Science.gov (United States)

Xu, Zhujing; Li, Tongcang

2017-09-01

The linear momentum and angular momentum of virtual photons of quantum vacuum fluctuations can induce the Casimir force and the Casimir torque, respectively. While the Casimir force has been measured extensively, the Casimir torque has not been observed experimentally though it was predicted over 40 years ago. Here we propose to detect the Casimir torque with an optically levitated nanorod near a birefringent plate in vacuum. The axis of the nanorod tends to align with the polarization direction of the linearly polarized optical tweezer. When its axis is not parallel or perpendicular to the optical axis of the birefringent crystal, it will experience a Casimir torque that shifts its orientation slightly. We calculate the Casimir torque and Casimir force acting on a levitated nanorod near a birefringent crystal. We also investigate the effects of thermal noise and photon recoils on the torque and force detection. We prove that a levitated nanorod in vacuum will be capable of detecting the Casimir torque under realistic conditions, and will be an important tool in precision measurements.

Reducing torque ripples in permanent magnet synchronous motor

Directory of Open Access Journals (Sweden)

Rihab Abdelmoula

2017-09-01

Full Text Available Permanent magnet synchronous motors (PMSMs are exceptionally promising thanks to their many advantages compared with other types of electrical machines. Indeed, PMSMs are characterized by their important torque density, light weight, high air gap flux density, high acceleration, high efficiency and strong power-to-weight ratio. A surface-mounted PMSM (SPMSM is used in this work. The SPMSM is built using a 2D finite element method (FEM. Cogging torque, torque ripples and back-EMF are examined during the design process in order to obtain sinusoidal back-EMF and to minimise torque ripples which are one of the major problems with PMSMs. Two procedures are used to reduce the cogging torque of SPMSM: the effect of slot opening and the influence of skewing the stator laminations. Cogging torque factor tc and the torque ripples factor tr have been calculated to compare the two configurations (open slots and closed slots. Then, the configuration with closed slots is utilised with skewing the stator laminations for different angle 0°, 10° and 15°.

Current-induced torques and interfacial spin-orbit coupling

KAUST Repository

Haney, Paul M.

2013-12-19

In bilayer systems consisting of an ultrathin ferromagnetic layer adjacent to a metal with strong spin-orbit coupling, an applied in-plane current induces torques on the magnetization. The torques that arise from spin-orbit coupling are of particular interest. Here we use first-principles methods to calculate the current-induced torque in a Pt-Co bilayer to help determine the underlying mechanism. We focus exclusively on the analog to the Rashba torque, and do not consider the spin Hall effect. The details of the torque depend strongly on the layer thicknesses and the interface structure, providing an explanation for the wide variation in results found by different groups. The torque depends on the magnetization direction in a way similar to that found for a simple Rashba model. Artificially turning off the exchange spin splitting and separately the spin-orbit coupling potential in the Pt shows that the primary source of the “fieldlike” torque is a proximate spin-orbit effect on the Co layer induced by the strong spin-orbit coupling in the Pt.

Betões de elevado desempenho de custo reduzido utilizando materiais correntes

OpenAIRE

Camões, Aires; Aguiar, J. L. Barroso de; Rocha, Patrício; Jalali, Said; Pereira, J. C.

1999-01-01

Para a produção de betões de elevado desempenho (BED) é genericamente aceite que são necessários materiais criteriosamente seleccionados, obrigando assim a um acréscimo significativo do custo inicial dos BED quando confrontados com betões correntes. Este trabalho pretende abordar duas características: possibilidade de produzir betões de elevado desempenho que incorporam materiais considerados correntes, nomeadamente cinzas volantes com teor de inqueimados superior ao máximo regulamentar e ine...

Actividad funcional cerebral en estado de reposo: REDES EN CONEXIÓN

Science.gov (United States)

Proal, Erika; Alvarez-Segura, Mar; de la Iglesia-Vayá, Maria; Martí-Bonmatí, Luis; Castellanos, F. Xavier

2015-01-01

Resumen El análisis de la conectividad funcional mediante resonancia magnética funcional (RMf) puede llevarse a cabo durante la realización de una tarea, la percepción de un estímulo o en estado de reposo. Estos análisis han demostrado su fiabilidad y reproducibilidad con diferentes enfoques (matemáticos, estadísticos, físicos) para seleccionar los vóxeles activados. El estudio de la señal de baja frecuencia en la actividad cerebral a través del contraste BOLD en estado de reposo ha revelado patrones de actividad cortical sincronizados, permitiendo describir la arquitectura funcional intrínseca del cerebro humano. La comunidad científica internacional dispone de recursos compartidos que contribuirán mediante este análisis de RMf en estado de reposo a la obtención de diagnósticos y tratamientos más precisos y avanzados en el campo de las neurociencias. PMID:21365601

Desempenho motor fino e funcionalidade em crianças com síndrome de Down Fine motor performance and functionality in children with Down syndrome

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Aline Cirelli Coppede

2012-12-01

Full Text Available O objetivo do estudo foi comparar crianças com síndrome de Down (SD e crianças típicas quanto ao desempenho motor fino, avaliado pela Bayley Scales of Infant and Toddler Development - Third Edition (BSITD-III, e o desempenho em autocuidado segundo o Inventário Pediátrico de Avaliação de Incapacidade (PEDI; e investigar associação entre ambos os domínios. Participaram 12 crianças típicas e 12 crianças com SD, avaliadas na idade de 2 anos. As crianças com SD apresentaram desempenho motor fino e funcionalidade inferior às crianças típicas, possivelmente por dificuldades em desempenhar tarefas que exijam destreza e coordenação manual, como as que compõem a BSITD-III. Apesar disso, sua pontuação em autocuidado foi adequada para a faixa etária, possivelmente porque as habilidades funcionais exigidas nesse período, como retirar calçados/vestimenta, impõem menor demanda motora fina do que tarefas da BSITD-III. Esse fato pode ter contribuído para o bom desempenho funcional das crianças com SD, e para a ausência de associação entre os domínios. Fatores como os cuidados oferecidos à criança pelos cuidadores, bem como ambientes estimuladores provavelmente também contribuíram para os resultados.The aim of study was to compare typically-developing children and children with Down syndrome (DS for their fine motor performance, measured by the Bayley Scales of Infant and Toddler Development - Third Edition (BSITD-III, and for their functional performance in self-care, measured by the Pediatric Evaluation of Disability Inventory (PEDI. Associations between these areas were also investigated. Twelve typically-developing children and 12 children with DS were assessed at the age of 2 years. The children with DS performed poorly in fine motor skills when compared with typical children, which may be explained by the complex motor skills involved in the BSITD-III's tasks. Their self-care scores were also lower in comparison with the

Estimating Torque Imparted on Spacecraft Using Telemetry

Science.gov (United States)

Lee, Allan Y.; Wang, Eric K.; Macala, Glenn A.

2013-01-01

There have been a number of missions with spacecraft flying by planetary moons with atmospheres; there will be future missions with similar flybys. When a spacecraft such as Cassini flies by a moon with an atmosphere, the spacecraft will experience an atmospheric torque. This torque could be used to determine the density of the atmosphere. This is because the relation between the atmospheric torque vector and the atmosphere density could be established analytically using the mass properties of the spacecraft, known drag coefficient of objects in free-molecular flow, and the spacecraft velocity relative to the moon. The density estimated in this way could be used to check results measured by science instruments. Since the proposed methodology could estimate disturbance torque as small as 0.02 N-m, it could also be used to estimate disturbance torque imparted on the spacecraft during high-altitude flybys.

Robust spin transfer torque in antiferromagnetic tunnel junctions

KAUST Repository

Saidaoui, Hamed Ben Mohamed

2017-04-18

We theoretically study the current-induced spin torque in antiferromagnetic tunnel junctions, composed of two semi-infinite antiferromagnetic layers separated by a tunnel barrier, in both clean and disordered regimes. We find that the torque enabling electrical manipulation of the Néel antiferromagnetic order parameter is out of plane, ∼n×p, while the torque competing with the antiferromagnetic exchange is in plane, ∼n×(p×n). Here, p and n are the Néel order parameter direction of the reference and free layers, respectively. Their bias dependence shows behavior similar to that in ferromagnetic tunnel junctions, the in-plane torque being mostly linear in bias, while the out-of-plane torque is quadratic. Most importantly, we find that the spin transfer torque in antiferromagnetic tunnel junctions is much more robust against disorder than that in antiferromagnetic metallic spin valves due to the tunneling nature of spin transport.

Torque control for electric motors

Science.gov (United States)

Bernard, C. A.

1980-01-01

Method for adjusting electric-motor torque output to accomodate various loads utilizes phase-lock loop to control relay connected to starting circuit. As load is imposed, motor slows down, and phase lock is lost. Phase-lock signal triggers relay to power starting coil and generate additional torque. Once phase lock is recoverd, relay restores starting circuit to its normal operating mode.

Bevel gear driver and method having torque limit selection

Science.gov (United States)

Cook, Joseph S., Jr.

1994-08-01

This invention comprises a torque drive mechanism utilizing axially translatable, mutually engageable transmission members having mating crown gears, driven and driving members with a three-element drive train being biased together by resilient means or by a fluid actuator system, the apparatus being operable to transmit a precisely controlled degree of torque to a driven member. The apparatus is applicable for use in hand tools and as a replacement for impact torque drivers, torque wrenches, motorized screw drivers, or the like, wherein the applied torque must be precisely controlled or limited. The bevel torque drive includes a drive gear which is axially displaceable and rotatable within cylindrical driver housing, a rotatable intermediate gear, and an output gear. Key rotationally secures displaceable gear with respect to input shaft but permits axial movement therebetween. A thrust bearing is preferably connected to the lower end of shaft for support to reduce play and friction between shaft and a transmission joint disc during rotation of the gear train. Coaxially mounted coiled spring is footed against displaceable gear for biasing the displaceable gear toward and into engagement with the intermediate gear for driving intermediate gear and output gear. Torque control is achieved by the use of straight or spiral beveled gears which are of configurations adapted to withdraw from mutual engagement upon the torque exceeding a predetermined limit. The novel, advantageous features of the invention include the configuration of the mating, crown gear sets and the axially translatable, slidable drive gear. The mechanism is capable of transmitting a high degree of torque within a narrow, compact transmission housing. The compact size and narrow, elongated configuration of the housing is particularly applicable for use in hand tools and in multiple torque driver mechanisms in which it is necessary to drive multiple fasteners which are located in close proximity. Prior

Torque Measurement at the Single Molecule Level

Science.gov (United States)

Forth, Scott; Sheinin, Maxim Y.; Inman, James; Wang, Michelle D.

2017-01-01

Methods for exerting and measuring forces on single molecules have revolutionized the study of the physics of biology. However, it is often the case that biological processes involve rotation or torque generation, and these parameters have been more difficult to access experimentally. Recent advances in the single molecule field have led to the development of techniques which add the capability of torque measurement. By combining force, displacement, torque, and rotational data, a more comprehensive description of the mechanics of a biomolecule can be achieved. In this review, we highlight a number of biological processes for which torque plays a key mechanical role. We describe the various techniques that have been developed to directly probe the torque experienced by a single molecule, and detail a variety of measurements made to date using these new technologies. We conclude by discussing a number of open questions and propose systems of study which would be well suited for analysis with torsional measurement techniques. PMID:23541162

Angular dependence of spin-orbit spin-transfer torques

KAUST Repository

Lee, Ki-Seung

2015-04-06

In ferromagnet/heavy-metal bilayers, an in-plane current gives rise to spin-orbit spin-transfer torque, which is usually decomposed into fieldlike and dampinglike torques. For two-dimensional free-electron and tight-binding models with Rashba spin-orbit coupling, the fieldlike torque acquires nontrivial dependence on the magnetization direction when the Rashba spin-orbit coupling becomes comparable to the exchange interaction. This nontrivial angular dependence of the fieldlike torque is related to the Fermi surface distortion, determined by the ratio of the Rashba spin-orbit coupling to the exchange interaction. On the other hand, the dampinglike torque acquires nontrivial angular dependence when the Rashba spin-orbit coupling is comparable to or stronger than the exchange interaction. It is related to the combined effects of the Fermi surface distortion and the Fermi sea contribution. The angular dependence is consistent with experimental observations and can be important to understand magnetization dynamics induced by spin-orbit spin-transfer torques.

Angular dependence of spin-orbit spin-transfer torques

KAUST Repository

Lee, Ki-Seung; Go, Dongwook; Manchon, Aurelien; Haney, Paul M.; Stiles, M. D.; Lee, Hyun-Woo; Lee, Kyung-Jin

2015-01-01

In ferromagnet/heavy-metal bilayers, an in-plane current gives rise to spin-orbit spin-transfer torque, which is usually decomposed into fieldlike and dampinglike torques. For two-dimensional free-electron and tight-binding models with Rashba spin-orbit coupling, the fieldlike torque acquires nontrivial dependence on the magnetization direction when the Rashba spin-orbit coupling becomes comparable to the exchange interaction. This nontrivial angular dependence of the fieldlike torque is related to the Fermi surface distortion, determined by the ratio of the Rashba spin-orbit coupling to the exchange interaction. On the other hand, the dampinglike torque acquires nontrivial angular dependence when the Rashba spin-orbit coupling is comparable to or stronger than the exchange interaction. It is related to the combined effects of the Fermi surface distortion and the Fermi sea contribution. The angular dependence is consistent with experimental observations and can be important to understand magnetization dynamics induced by spin-orbit spin-transfer torques.

Desempenho acadêmico em métodos quantitativos nos cursos de Ciências Contábeis

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Manoel Raimundo Santana Farias

2015-08-01

Full Text Available Este estudo investigou variáveis que explicam o desempenho acadêmico (academic achievement nas disciplinas de métodos quantitativos no curso de ciências contábeis. Realizou-se uma pesquisa empírica na Universidade Federal do Pará com objetivo de encontrar proxies associadas à variável dependente desempenho acadêmico. Assim, com a finalidade de ratificar os achados desta pesquisa, foi realizado teste estatístico de análise de regressão por meio do software SPSS®. A análise inferencial conjecturou oito variáveis que explicariam o desempenho dos discentes, quais sejam: desempenho anterior em matemática e/ou estatística, índice de participação do discente na realização das disciplinas, turno de estudo, idade, gênero, estado civil, possuir ou não renda e origem escolar. Após a realização da análise de regressão com essas variáveis, o modelo mais adequado para representação do desempenho dos discentes foi o que considerou apenas as seguintes variáveis: desempenho anterior em matemática e/ ou estatística, índice de participação do discente na realização das disciplinas, o turno de estudo e a idade, as quais apresentaram significância estatística. Esses resultados ratificam que características pessoais determinam o desempenho de discentes de ciências contábeis, como afirmado por Santos (2012, referenciada neste estudo. Futuras pesquisas podem ratificar as variáveis aqui trabalhadas e expandir tal estudo a fim de obter um modelo mais representativo sobre o desempenho dos discentes em métodos quantitativos nos cursos de ciências contábeis.

Dinámica neuronal del circuito motor: un estudio de resonancia magnética funcional

OpenAIRE

Batista García-Ramó, Karla; Rodríguez Rojas, Rafael; Carballo Barreda, Maylén

2012-01-01

La modelación de redes neuronales que describan la interacción funcional del circuito cerebral formado por los ganglios basales (GB), el tálamo y la corteza está limitada por las simplificaciones necesarias para reproducir sus propiedades biológicas. Este trabajo tiene como objetivo general modelar el circuito GB-tálamo-corteza para la selección de un programa motor, sobre la base del patrón de conectividad funcional obtenido por imágenes de resonancia magnética nuclear funcional (RMNf). Se i...

Confiança e Desempenho de Equipes [doi: 10.5329/RECADM.2013005

Directory of Open Access Journals (Sweden)

João Bosco Castro Araujo

2013-04-01

Full Text Available Este artigo teve como objetivo analisar como a confiança se relaciona com o desempenho de equipes. Entende-se confiança como uma relação entre duas ou mais partes, na qual há expectativa mútua do cumprimento do que foi combinado; e alto desempenho, o atingimento ou superação das metas estabelecidas. Foi realizado um estudo de caso de caráter qualitativo, em uma empresa do setor de construção civil, a partir da seleção intencional de uma equipe de alto desempenho (Equipe Alfa e outra de baixo desempenho (Equipe Beta. A coleta de dados foi realizada por meio de análise documental, de entrevistas individuais e de observação de reunião. Os resultados indicaram que a Equipe Alfa demonstrou comportamentos relativos à confiança transacional e transformadora, encontrando-se no estágio de realização; apresenta disposição para desenvolver-se, correr riscos, inovar e melhorar; e alto desempenho em termos do atingimento das metas propostas. A Equipe Beta apresentou comportamentos mais relacionados à confiança transacional, encontrando-se no estágio de formação; apresenta disposição para consistência, compromisso e capacidade; e baixo desempenho. Esses resultados indicam que há uma relação entre a confiança transacional e transformadora e o alto desempenho em equipes.   Palavras-chave: Confiança; Confiança transformadora; Confiança transacional; Equipes de alto desempenho; Relações intraequipes.     TRUST AND TEAM PERFORMANCE   ABSTRACT This paper aimed to analyze the relationship between trust and teams performance. Trust is understood as a relation between two or more parties, with a mutual expectation to fulfill what was defined by the parties; and high performance is the reaching or the overcoming of the established goals. We realized a qualitative case study in a company of the civil construction sector. We intentionally selected one high performance team (Alfa team and another low performance team (Beta team

RELAÇÃO DA FOLGA ORGANIZACIONAL COM MEDIDAS DE DESEMPENHO DE EMPRESAS BRASILEIRAS

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Ilse Maria Beuren

2015-07-01

Full Text Available O estudo objetiva identificar a relação da folga organizacional (potencial, inabsorvida e absorvida com medidas de desempenho (ROA, ROE e ROI em empresas brasileiras. A pesquisa descritiva com abordagem quantitativa foi realizada utilizando dados financeiros disponíveis na base de dados Economática@. A população da pesquisa compreendeu as 500 Maiores e Melhores empresas de 2010 segundo a Revista Exame; e a amostra as 119 listadas na BM&FBovespa. Os resultados mostram que as empresas apresentaram folga organizacional, na ordem folga potencial, absorvida e inabsorvida. Os modelos de análise indicaram relação significativa entre as variáveis ROA, ROE, ROI e as variáveis folga potencial, absorvida, inabsorvida. No entanto, a folga potencial, analisada pelos indicadores ROE e ROI, apresentou sinal negativo, logo, quanto maior a folga, menor o respectivo índice de desempenho. Observou-se ainda uma tendência da folga potencial ser inversa ao desempenho da empresa, com exceção do índice de desempenho ROI, que não apresentou significância.

O RETORNO POR EMPREGADO COMO INDICADOR DE DESEMPENHO DAS EMPRESAS

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Francisca Soraia Ferreira Leite

2013-12-01

Full Text Available Com as transformações no ambiente de negócios, os ativos intangíveis, potencialmente gerados pelo capital intelectual, ganharam importância. Este estudo tem como objetivo analisar e testar uma métrica alternativa de avaliação de desempenho que leva em conta os recursos humanos da empresa: o Retorno por Empregado (RE. Uma pesquisa exploratória foi realizada através do estudo de caso de três empresas com ações negociadas na BM&FBOVESPA no período 2006-2009. A partir das demonstrações financeiras das empresas, foram medidos seus desempenhos pelas métricas tradicionais, Retorno sobre Ativo e Retorno sobre Patrimônio Líquido, e pelo RE. O valor das ações de cada empresa foi usado como referência para criação de valor. Um estudo empírico complementar apontou que a correlação entre o RE e o preço das ações foi mais alta e significativa do que a correlação entre os indicadores tradicionais para a empresa mais intensiva em capital intelectual. Para as empresas intensivas em capital físico e em mão de obra, os indicadores de desempenho tradicionais apresentaram correlação mais alta. Sugere-se que a métrica alternativa seja um importante índice para empresas intensivas em capital intelectual. Reforça-se que tal medida de desempenho corporativo, que incorpora o efeito da força de trabalho intelectual, é uma contribuição importante à literatura sobre intangíveis.

Fatores determinantes da capacidade funcional entre idosos

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Tereza Etsuko da Costa Rosa

2003-02-01

Full Text Available OBJETIVO; Investigar a influência de fatores socioeconômicos e demográficos relativos à saúde, bem como os fatores ligados às atividades sociais e à avaliação subjetiva da saúde sobre a capacidade funcional dos idosos. MÉTODOS: Estudo transversal, integrante de estudo multicêntrico, em amostra representativa do município de São Paulo, realizado em 1989. A capacidade funcional foi avaliada através da escala de atividades da vida diária pessoal e instrumental e investigada como variável dicotômica: ausência de dependência - incapacidade/dificuldade em nenhuma das atividades versus presença de dependência moderada/grave - incapacidade/dificuldade em 4 ou mais atividades. Análise de regressão logística múltipla foi aplicada aos fatores hierarquicamente agrupados. RESULTADOS: As características que se associaram com a dependência moderada/grave foram analfabetismo, ser aposentado, ser pensionista, ser dona de casa, não ser proprietário da moradia, ter mais de 65 anos, ter composição familiar multigeracional, ter sido internado nos últimos 6 meses, ser "caso" no rastreamento de saúde mental, não visitar amigos, ter problemas de visão, ter história de derrame, não visitar parentes e ter avaliação pessimista da saúde ao se comparar com seus pares. CONCLUSÕES: As características identificadas que se associaram à dependência moderada/grave sugerem uma complexa rede causal do declínio da capacidade funcional. Pode-se supor, entretanto, que ações preventivas especificamente voltadas para certos fatores podem propiciar benefícios para o prolongamento do bem estar da população idosa.

Fatores determinantes da capacidade funcional entre idosos

Directory of Open Access Journals (Sweden)

Rosa Tereza Etsuko da Costa

2003-01-01

Full Text Available OBJETIVO; Investigar a influência de fatores socioeconômicos e demográficos relativos à saúde, bem como os fatores ligados às atividades sociais e à avaliação subjetiva da saúde sobre a capacidade funcional dos idosos. MÉTODOS: Estudo transversal, integrante de estudo multicêntrico, em amostra representativa do município de São Paulo, realizado em 1989. A capacidade funcional foi avaliada através da escala de atividades da vida diária pessoal e instrumental e investigada como variável dicotômica: ausência de dependência - incapacidade/dificuldade em nenhuma das atividades versus presença de dependência moderada/grave - incapacidade/dificuldade em 4 ou mais atividades. Análise de regressão logística múltipla foi aplicada aos fatores hierarquicamente agrupados. RESULTADOS: As características que se associaram com a dependência moderada/grave foram analfabetismo, ser aposentado, ser pensionista, ser dona de casa, não ser proprietário da moradia, ter mais de 65 anos, ter composição familiar multigeracional, ter sido internado nos últimos 6 meses, ser "caso" no rastreamento de saúde mental, não visitar amigos, ter problemas de visão, ter história de derrame, não visitar parentes e ter avaliação pessimista da saúde ao se comparar com seus pares. CONCLUSÕES: As características identificadas que se associaram à dependência moderada/grave sugerem uma complexa rede causal do declínio da capacidade funcional. Pode-se supor, entretanto, que ações preventivas especificamente voltadas para certos fatores podem propiciar benefícios para o prolongamento do bem estar da população idosa.

Programación funcional: conceptos y perspectivas

OpenAIRE

González Osorio, Fabio Augusto

2011-01-01

El presente artículo muestra conceptos subyacentes a la programación funcional, así como características que los hacen un enfoque particular y novedoso de la programación que lo convierten en una clara opción frente al enfoque imperativo convencional en el área del desarrollo de software.

O papel mediador entre confiança e desempenho organizacional

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Marco Tulio Fundão Zanini

2014-03-01

Full Text Available Neste artigo, busca-se contribuir para as discussões sobre a relação entre confiança e desempenho organizacional numa perspectiva econômica. Examinou-se o papel mediador entre confiança e desempenho organizacional a partir da análise da confiança como um elemento de coordenação informal dentro das organizações. Observou-se que a confiança interpessoal é um elemento central para a melhor compreensão dos contratos relacionais, como os contratos de trabalho, e que investimentos na criação e na manutenção de ambientes de trabalho baseados em confiança devem observar uma racionalidade econômica. Por meio de revisão na literatura para buscar compreender a necessidade e os benefícios de contextos sociais de alta e baixa confiança, concluiu-se que confiança é um elemento essencial para a execução de específicas tarefas organizacionais e observou-se sua relação mediadora com o desempenho.

Condicionantes de desempenho dos projetos de software e a influência da maturidade em gestão de projetos.

OpenAIRE

Renato de Oliveira Moraes

2004-01-01

Este trabalho procurou averiguar os efeitos da maturidade em gestão de projetos da organização executante sobre a relação entre certos condicionantes de desempenho e o desempenho dos projetos de software. Para tanto, foi feito um levantamento em 131 projetos de software cujos resultados mostram que, nas organizações de maior maturidade em gestão de projetos, certos elementos condicionantes do desempenho têm uma menor influência sobre as diferentes dimensões do desempenho dos projetos. O perfi...

A New Circuit Model for Spin-Torque Oscillator Including Perpendicular Torque of Magnetic Tunnel Junction

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Hyein Lim

2013-01-01

Full Text Available Spin-torque oscillator (STO is a promising new technology for the future RF oscillators, which is based on the spin-transfer torque (STT effect in magnetic multilayered nanostructure. It is expected to provide a larger tunability, smaller size, lower power consumption, and higher level of integration than the semiconductor-based oscillators. In our previous work, a circuit-level model of the giant magnetoresistance (GMR STO was proposed. In this paper, we present a physics-based circuit-level model of the magnetic tunnel junction (MTJ-based STO. MTJ-STO model includes the effect of perpendicular torque that has been ignored in the GMR-STO model. The variations of three major characteristics, generation frequency, mean oscillation power, and generation linewidth of an MTJ-STO with respect to the amount of perpendicular torque, are investigated, and the results are applied to our model. The operation of the model was verified by HSPICE simulation, and the results show an excellent agreement with the experimental data. The results also prove that a full circuit-level simulation with MJT-STO devices can be made with our proposed model.

Desempenho escolar e autocenceito de alunos atendidos em serviços psicopedagógicos

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Suze Sabino da Silva

Full Text Available Este estudo teve como objetivo investigar o desempenho escolar e autoconceito de crianças com queixa escolar. Participaram do estudo 78 alunos da 4ª série do ensino fundamental da rede pública do Distrito Federal, sendo 46 atendidos em um Serviço de Apoio Psicopedagógico e 32 de classes de aceleração da aprendizagem. O desempenho acadêmico foi avaliado por uma escala de notas atribuídas por seus professores e para avaliar o autoconceito foi utilizado o Perfil de Autopercepção para Crianças. Os resultados não indicaram diferenças significativas entre os alunos atendidos no serviço psicopedagógico e alunos das classes de aceleração com relação ao desempenho escolar e autoconceito. Observou-se ganhos significativos no desempenho escolar no segundo semestre, em comparação ao primeiro semestre de 2001, por parte dos dois grupos avaliados. Foram constatadas diferenças significativas entre gênero com relação ao autoconceito.

40 CFR 91.306 - Dynamometer torque cell calibration.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Dynamometer torque cell calibration... Provisions § 91.306 Dynamometer torque cell calibration. (a)(1) Any lever arm used to convert a weight or a force through a distance into a torque must be used in a horizontal position for horizontal shaft...

40 CFR 90.306 - Dynamometer torque cell calibration.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Dynamometer torque cell calibration... Emission Test Equipment Provisions § 90.306 Dynamometer torque cell calibration. (a)(1) Any lever arm used to convert a weight or a force through a distance into a torque must be used in a horizontal position...

Efeitos de variáveis individuais e contextuais sobre desempenho individual no trabalho Effects of individuals and contextual variables on individual performance at work

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Francisco Antonio Coelho Junior

2011-08-01

Full Text Available O presente trabalho objetivou testar empiricamente um modelo teórico multinível de predição de desempenho individual no trabalho. As variáveis antecedentes investigadas, isoladas ou em interação, corresponderam à idade, gênero, cargo, grau de escolaridade, tempo de serviço e percepção de suporte à aprendizagem, medidas no nível individual e de contexto, e satisfação no trabalho, de nível individual. A pesquisa foi realizada em uma empresa pública, do ramo de pesquisas agropecuária e atuação nacional. A amostra (N = 808 contou com funcionários distribuídos em 45 unidades centralizadas e descentralizadas da empresa pelo Brasil. A coleta de dados foi realizada à distância, via e-mail. Os resultados multiníveis corroboraram o modelo teórico de pesquisa hipotetizado e evidenciaram que a variância de desempenho foi explicada por distintos preditores de nível individual e de contexto, isoladamente ou em interação.This paper aims to empirically test a theoretical multilevel model for the prediction of individual performance at work. Antecedent variables, isolated or in interaction, were age, gender, function, scholarity, period of function and perception of learning support, in the individual and contextual levels, and satisfaction at work, an individual variable. This study was accomplished in a public corporation which deals with agricultural research in a national scope. The participants (N = 808 were distribute in 45 central and noncentral units for the Brazil. Data collection was done online, by e-mail. The multilevel results confirm the hypothetic theoretical model and make evident that the performance's variance were predicted by different individuals and context variables, isolated or in interaction.

Analysis of a non-contact magnetoelastic torque transducer

International Nuclear Information System (INIS)

Andreescu, R.; Spellman, B.; Furlani, E.P.

2008-01-01

Results are presented for the performance of a magnetoelastic torque transducer that converts a torque-induced strain in a non-magnetic shaft into changes in a measurable magnetic field. The magnetic field is generated by a thin magnetostrictive layer that is coated onto the circumference of the shaft. The layer is magnetized and has an initial residual strain. The magnetization within the layer rotates in response to changes in the strain which occur when the shaft is torqued. The magnetic field produced by the layer changes with the magnetization and this can be sensed by a magnetometer to monitor the torque on the shaft. In this paper, a phenomenological theory is developed for predicting the performance of the transducer. The theory can be used to predict the magnetic field distribution of the transducer as a function of the physical properties of the magnetic coating, its residual strain, and the applied torque. It enables rapid parametric analysis of transducer performance, which is useful for the development and optimization of novel non-contact torque sensors

Improvement of the Torque-Speed Performance and Drive Efficiency in an SRM Using an Optimal Torque Sharing Function

Directory of Open Access Journals (Sweden)

Wei Ye

2018-05-01

Full Text Available In this paper, by evaluating the extreme value of the qth-power current, a torque sharing function (TSF family for reducing the torque ripples in the switched reluctance motor (SRM is proposed. The optimization criteria of the TSF has two secondary objectives, including the maximization of the torque-speed range and the minimization of copper loss. The evaluation indices in terms of the peak phase current, the rms (root mean square phase current, and the torque ripple factor are compared between the proposed TSF family and four conventional TSFs including linear, sinusoidal, exponential, and cubic TSFs. An optimization objective function that combines the maximum absolute value of the rate-of-change of the flux linkage (MAV-RCFL and the qth-power of current is proposed and a weighting factor is used to balance the influence of the two optimization objectives. An optimal TSF can be easily obtained by solving the optimization problem from the TSF family. The proposed TSF is validated by using simulations and experiments with a three-phase 6/4 SRM with 7.5 kW, 3000 rpm, and 270 V DC-link voltage. The dynamic simulation model is implemented in Matlab/Simulink. The results demonstrate the validity and superiority of the proposed control method; the optimal TSF provides better torque-speed performance, and a better reduction in copper loss and torque ripples at high speed, as compared to conventional TSFs.

ESTRATÉGIAS SUSTENTÁVEIS E DESEMPENHO EXPORTADOR NO SETOR MOVELEIRO PARANAENSE

Directory of Open Access Journals (Sweden)

Adilson Carlos Da Rocha

2014-02-01

Full Text Available O presente estudo objetiva compreender como as estratégias de gestão sustentável se relacionam com o desempenho exportador em uma empresa industrial de móveis planejados. A pesquisa caracteriza-se como qualitativa e adotou como método o estudo de caso. As estratégias sustentáveis foram analisadas com base nos modelos de Placet, Anderson, Fowler (2005 e Lacy et al. (2010, buscando-se compreender aspectos referentes a gestão ambiental, a responsabilidade social e a integração da sustentabilidade na estratégia empresarial. O desempenho exportador foi analisado a partir dos estudos de Papadopoulos e Martín (2010 que analisam o desempenho por meio da experiência internacional e das dimensões estratégica e econômica. Os principais resultados revelaram que a empresa possui preocupações com o meio ambiente, procurando utilizar insumos mais sustentáveis e investindo em inovação para melhorar seus processos.

Multi-digit maximum voluntary torque production on a circular object

Science.gov (United States)

SHIM, JAE KUN; HUANG, JUNFENG; HOOKE, ALEXANDER W.; LATSH, MARK L.; ZATSIORSKY, VLADIMIR M.

2010-01-01

Individual digit-tip forces and moments during torque production on a mechanically fixed circular object were studied. During the experiments, subjects positioned each digit on a 6-dimensional force/moment sensor attached to a circular handle and produced a maximum voluntary torque on the handle. The torque direction and the orientation of the torque axis were varied. From this study, it is concluded that: (1) the maximum torque in the closing (clockwise) direction was larger than in the opening (counter clockwise) direction; (2) the thumb and little finger had the largest and the smallest share of both total normal force and total moment, respectively; (3) the sharing of total moment between individual digits was not affected by the orientation of the torque axis or by the torque direction, while the sharing of total normal force between the individual digit varied with torque direction; (4) the normal force safety margins were largest and smallest in the thumb and little finger, respectively. PMID:17454086

Comparison of different passive knee extension torque-angle assessments

International Nuclear Information System (INIS)

Freitas, Sandro R; Vaz, João R; Bruno, Paula M; Valamatos, Maria J; Mil-Homens, Pedro

2013-01-01

Previous studies have used isokinetic dynamometry to assess joint torques and angles during passive extension of the knee, often without reporting upon methodological errors and reliability outcomes. In addition, the reliability of the techniques used to measure passive knee extension torque-angle and the extent to which reliability may be affected by the position of the subjects is also unclear. Therefore, we conducted an analysis of the intra- and inter-session reliability of two methods of assessing passive knee extension: (A) a 2D kinematic analysis coupled to a custom-made device that enabled the direct measurement of resistance to stretch and (B) an isokinetic dynamometer used in two testing positions (with the non-tested thigh either flexed at 45° or in the neutral position). The intra-class correlation coefficients (ICCs) of torque, the slope of the torque-angle curve, and the parameters of the mathematical model that were fit to the torque-angle data for the above conditions were measured in sixteen healthy male subjects (age: 21.4 ± 2.1 yr; BMI: 22.6 ± 3.3 kg m −2 ; tibial length: 37.4 ± 3.4 cm). The results found were: (1) methods A and B led to distinctly different torque-angle responses; (2) passive torque-angle relationship and stretch tolerance were influenced by the position of the non-tested thigh; and (3) ICCs obtained for torque were higher than for the slope and for the mathematical parameters that were fit to the torque-angle curve. In conclusion, the measurement method that is used and the positioning of subjects can influence the passive knee extension torque-angle outcome. (paper)

Spin-Stabilized Spacecrafts: Analytical Attitude Propagation Using Magnetic Torques

Directory of Open Access Journals (Sweden)

Roberta Veloso Garcia

2009-01-01

Full Text Available An analytical approach for spin-stabilized satellites attitude propagation is presented, considering the influence of the residual magnetic torque and eddy currents torque. It is assumed two approaches to examine the influence of external torques acting during the motion of the satellite, with the Earth's magnetic field described by the quadripole model. In the first approach is included only the residual magnetic torque in the motion equations, with the satellites in circular or elliptical orbit. In the second approach only the eddy currents torque is analyzed, with the satellite in circular orbit. The inclusion of these torques on the dynamic equations of spin stabilized satellites yields the conditions to derive an analytical solution. The solutions show that residual torque does not affect the spin velocity magnitude, contributing only for the precession and the drift of the spacecraft's spin axis and the eddy currents torque causes an exponential decay of the angular velocity magnitude. Numerical simulations performed with data of the Brazilian Satellites (SCD1 and SCD2 show the period that analytical solution can be used to the attitude propagation, within the dispersion range of the attitude determination system performance of Satellite Control Center of Brazil National Research Institute.

PREFACE: The Science of Making Torque from Wind 2014 (TORQUE 2014)

Science.gov (United States)

Mann, Jakob; Bak, Christian; Bechmann, Andreas; Bingöl, Ferhat; Dellwik, Ebba; Dimitrov, Nikolay; Giebel, Gregor; Hansen, Martin O. L.; Jensen, Dorte Juul; Larsen, Gunner; Aagaard Madsen, Helge; Natarajan, Anand; Rathmann, Ole; Sathe, Ameya; Nørkær Sørensen, Jens; Nørkær Sørensen, Niels

2014-06-01

The 186 papers in this volume constitute the proceedings of the fifth Science of Making Torque from Wind conference, which is organized by the European Academy of Wind Energy (EAWE, www.eawe.eu). The conference, also called Torque 2014, is held at the Technical University of Denmark (DTU) 17-20 June 2014. The EAWE conference series started in 2004 in Delft, the Netherlands. In 2007 it was held in Copenhagen, in 2010 in Heraklion, Greece, and then in 2012 in Oldenburg, Germany. The global yearly production of electrical energy by wind turbines has grown approximately by 25% annually over the last couple of decades and covers now 2-3% of the global electrical power consumption. In order to make a significant impact on one of the large challenges of our time, namely global warming, the growth has to continue for a decade or two yet. This in turn requires research and education in wind turbine aerodynamics and wind resources, the two topics which are the main subjects of this conference. Similar to the growth in electrical power production by wind is the growth in scientific papers about wind energy. Over the last decade the number of papers has also grown by about 25% annually, and many research based companies all over the world are founded. Hence, the wind energy research community is rapidly expanding and the Torque conference series offers a good opportunity to meet and exchange ideas. We hope that the Torque 2014 will heighten the quality of the wind energy research, while the participants will enjoy each others company in Copenhagen. Many people have been involved in producing the Torque 2014 proceedings. The work by more than two hundred reviewers ensuring the quality of the papers is greatly appreciated. The timely evaluation and coordination of the reviews would not have been possible without the work of sixteen ''section editors'' all from DTU Wind Energy: Christian Bak, Andreas Bechmann, Ferhat Bingöl, Ebba Dellwik, Nikolay Dimitrov, Gregor Giebel, Martin

Study on Monitoring Rock Burst through Drill Pipe Torque

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Zhonghua Li

2015-01-01

Full Text Available This paper presents a new method to identify the danger of rock burst from the response of drill pipe torque during drilling process to overcome many defects of the conventional volume of drilled coal rubble method. It is based on the relationship of rock burst with coal stress and coal strength. Through theoretic analysis, the change mechanism of drill pipe torque and the relationship of drill pipe torque with coal stress, coal strength, and drilling speed are investigated. In light of the analysis, a new device for testing drill pipe torque is developed and a series of experiments is performed under different conditions; the results show that drill pipe torque linearly increases with the increase of coal stress and coal strength; the faster the drilling speed, the larger the drill pipe torque, and vice versa. When monitoring rock burst by drill pipe torque method, the index of rock burst is regarded as a function in which coal stress index and coal strength index are principal variables. The results are important for the forecast of rock burst in coal mine.

FRICTION TORQUE IN THE SLIDE BEARINGS

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BONDARENKO L. N.

2016-09-01

Full Text Available Summary. Problem statement. Until now slide bearings are used widely in engineering. But the calculation is made on obsolete method that is based on undetermined parameters such as wear of the bearing shell. It is accepted in the literature that if the shaft and liner material are homogeneous, the workpiece surface are cylindrical as they wear and contact between them occurs at all points contact arc. Research objective. The purpose of this study is determine a friction torque in the slide bearings of power-basis parameters. Conclusions. Since the friction is primarily responsible for wear of cinematic pairs “pin – liner” and “pivot – liner” slide bearings. It is shown that the friction torquesof angles wrap, that are obtained by the formulas and given in literature, are not only qualitatively but also quantitatively, namely, the calculation by literature to the formulas the friction torques are proportional to the angle wrap and the calculation by improved formulas the friction torques are inversely proportional to the angle wrap due to the reduction the normal pressure. Underreporting friction torque at large angle wrap is between 40 and 15 %. The difference in the magnitude of friction torque in the run-in and run-out cinematic pairs with real method of machining is 2...3 %, which it is possible to declare of reducing the finish of contacting surface of slide bearings.

Magnon-mediated Dzyaloshinskii-Moriya torque in homogeneous ferromagnets

KAUST Repository

Manchon, Aurelien

2014-12-01

In thin magnetic layers with structural inversion asymmetry and spin-orbit coupling, the Dzyaloshinskii-Moriya interaction arises at the interface. When a spin-wave current jm flows in a system with a homogeneous magnetization m, this interaction produces an effective fieldlike torque of the form TFLm×(z×jm) as well as a dampinglike torque, TDLm×[(z×jm)×m], the latter only in the presence of spin-wave relaxation (z is normal to the interface). These torques mediated by the magnon flow can reorient the time-averaged magnetization direction and display a number of similarities with the torques arising from the electron flow in a magnetic two-dimensional electron gas with Rashba spin-orbit coupling. This magnon-mediated spin-orbit torque can be efficient in the case of magnons driven by a thermal gradient.

GESTÃO POR COMPETÊNCIAS UM ESTUDO DOS IMPACTOS GERADOS NA AVALIAÇÃO DE DESEMPENHO E REMUNERAÇÃO

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Leila Vaz Silva

2011-03-01

Full Text Available A abordagem relacionada à gestão de pessoas baseada em competências tem sido um tema freqüente no ambiente organizacional. Considerando o cenário de constantes mudanças torna-se um desafio a manutenção da vantagem competitiva, o que justifica o interesse pelo tema. Este estudo teve o objetivo de descrever e identificar como é realizada a avaliação de desempenho em uma empresa do ramo de mineração que adotou a gestão de competências, analisando os reflexos do seu resultado na remuneração. Realizou-se uma pesquisa qualitativa por meio da estratégia do estudo de caso, sendo os dados coletados por meio de entrevistas e analisados adotando-se a análise do conteúdo. Como técnica auxiliar utilizou-se ainda a análise de desenhos, procurando retratar a percepção dos participantes sobre a gestão por competências. Os resultados indicam que a opção pela implantação do sistema de gestão por competências permitiu que os funcionários entendessem de modo mais claro o seu papel organizacional

Desarrollo de funciones ejecutivas, de la niñez a la juventud

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Julio C. Flores-Lázaro

2014-05-01

Full Text Available Las funciones ejecutivas se encuentran entre los procesos más complejos del humano; su desarrollo permite la conformación de diversas capacidades de control, y organización de la conducta y la cognición. En este artículo se presenta una extensa revisión de la literatura más relevante a nivel internacional sobre el tema. Se abarca el proceso de desarrollo desde la niñez hasta la juventud, analizando las características de desarrollo de las principales funciones ejecutivas. Se muestra que la hipótesis planteada por Victoria Anderson hace ya una década es correcta: las funciones ejecutivas se desarrollan de forma secuencial y curvilínea: un intenso progreso en la infancia, con una desaceleración a inicios de la adolescencia. También se analiza el efecto de otros factores adicionales a la edad como son el efecto de la escolaridad, los estilos parentales y el contexto cultural.

Relação familiar da pessoa idosa com comprometimento da capacidade funcional

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Luana Araújo dos Reis

2015-01-01

Full Text Available Objetivo: comprender la relación familiar de la persona adulta con comprometimiento de la capacidad funcional. Materiales y mé - todos: estudio exploratorio y descriptivo de abordaje cualitativo, fundamentado en el método de la historia oral, realizado con 15 adultos mayores asistidos por una unidad de salud de la familia, residentes con familiares y que presentaban comprometimiento de la capacidad funcional. Se recolectaron los datos en el período de marzo y abril del 2012, por medio de entrevistas en profundidad. Las categorías temáticas fueron: buena relación familiar, cambios en la relación familiar, sintiéndose un estorbo para la familia, sintiéndose abandonado por la familia. Resultado: el estudio ha revelado que las personas mayores con comprometimiento de la capacidad funcional vivencian sentimientos diversos que van desde la alegría porque son respetadas y tienen sus necesidades atendidas, hasta la tristeza y revuelta, por la adaptación negativa de la familia y el abandono de los hijos. Conclusión: la relación familiar de la persona mayor pasa por reajustes luego del comprometimiento de la capacidad funcional, lo que repercute significativamente en la dinámica de las relaciones. Desde esta comprensión, los profesionales de salud, sobre todo de enfermería, deben reconocer los retos a los que la familia afronta, orientarla y capacitarla para la atención a las demandas de cuidado presentadas por la persona mayor con comprometimiento de la capacidad funcional, y favorecer la realización del cuidado sin que esto desgaste las relaciones.

Interaction torque contributes to planar reaching at slow speed

Directory of Open Access Journals (Sweden)

Hoshi Fumihiko

2008-10-01

Full Text Available Abstract Background How the central nervous system (CNS organizes the joint dynamics for multi-joint movement is a complex problem, because of the passive interaction among segmental movements. Previous studies have demonstrated that the CNS predictively compensates for interaction torque (INT which is arising from the movement of the adjacent joints. However, most of these studies have mainly examined quick movements, presumably because the current belief is that the effects of INT are not significant at slow speeds. The functional contribution of INT for multijoint movements performed in various speeds is still unclear. The purpose of this study was to examine the contribution of INT to a planer reaching in a wide range of motion speeds for healthy subjects. Methods Subjects performed reaching movements toward five targets under three different speed conditions. Joint position data were recorded using a 3-D motion analysis device (50 Hz. Torque components, muscle torque (MUS, interaction torque (INT, gravity torque (G, and net torque (NET were calculated by solving the dynamic equations for the shoulder and elbow. NET at a joint which produces the joint kinematics will be an algebraic sum of torque components; NET = MUS - G - INT. Dynamic muscle torque (DMUS = MUS-G was also calculated. Contributions of INT impulse and DMUS impulse to NET impulse were examined. Results The relative contribution of INT to NET was not dependent on speed for both joints at every target. INT was additive (same direction to DMUS at the shoulder joint, while in the elbow DMUS counteracted (opposed to INT. The trajectory of reach was linear and two-joint movements were coordinated with a specific combination at each target, regardless of motion speed. However, DMUS at the elbow was opposed to the direction of elbow movement, and its magnitude varied from trial to trial in order to compensate for the variability of INT. Conclusion Interaction torque was important at

Estudio del impacto del ajedrez sobre las funciones ejecutivas en niños de edad escolar

OpenAIRE

Grau Pérez, Gonzalo; Moreira, Karen

2015-01-01

Las funciones ejecutivas (FE) engloban procesos cognitivos complejos, orientados al control y monitoreo de comportamientos dirigidos a metas. La estimulación de estas funciones a través de juegos como el ajedrez puede tener incidencia en el desempeño de los niños en ciertas áreas curriculares, ya que las FE juegan un papel relevante en los aprendizajes escolares. Hay evidencia que sugiere que el ajedrez podría ser beneficioso a nivel de estas funciones. Dado que las FE se desarrollan durante ...

Programacion funcional y lambda cálculo

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Jonatan Gómez Perdomo

1998-05-01

Full Text Available En la primera parte de este artículo se explican algunos conceptos de los lenguajes de programación, haciendo énfasis en las caracteristicas y propiedades de los lenguajes de programación funcional. En la segunda, se realiza una introducción al lambda cálculo puro, su notación, axiomas y reglas elementales.

Current-induced Rashba spin orbit torque in silicene

Energy Technology Data Exchange (ETDEWEB)

Chen, Ji, E-mail: muze7777@hdu.edu.cn [Department of Mathematics, School of Science, Hangzhou Dianzi University, Hangzhou 310018 (China); Peng, Yingzi [Department of Physics, School of Science, Hangzhou Dianzi University, Hangzhou 310018 (China); Center for Integrated Spintronic Devices, Hangzhou Dianzi University, Hangzhou 310018 (China); Zhou, Jie [Department of Mathematics, School of Science, Hangzhou Dianzi University, Hangzhou 310018 (China)

2017-06-15

Highlights: • The spin dynamics of a ferromagnetic layer coupled to a silicene is investigated. • The Rashba spin orbit torque is obtained and the well-known LLG equation is modified. • The explicit forms of spin orbit torques in Domain Wall and vortex is also obtained. - Abstract: We study theoretically the spin torque of a ferromagnetic layer coupled to a silicene in the presence of the intrinsic Rashba spin orbit coupling (RSOC) effect. By using gauge field method, we find that under the applied current, the RSOC can induce an effective field which will result in the spin precession of conduction electron without applying any magnetic field. We also derive the spin torques due to the RSOC, which generalize the Landau-Lifshitz-Gilbert (LLG) equation. The spin torques are related to the applied current, the carrier density and Rashba strength of the system.

Manipulating the voltage dependence of tunneling spin torques

KAUST Repository

Manchon, Aurelien

2012-10-01

Voltage-driven spin transfer torques in magnetic tunnel junctions provide an outstanding tool to design advanced spin-based devices for memory and reprogrammable logic applications. The non-linear voltage dependence of the torque has a direct impact on current-driven magnetization dynamics and on devices performances. After a brief overview of the progress made to date in the theoretical description of the spin torque in tunnel junctions, I present different ways to alter and control the bias dependence of both components of the spin torque. Engineering the junction (barrier and electrodes) structural asymmetries or controlling the spin accumulation profile in the free layer offer promising tools to design effcient spin devices.

Maximum Torque and Momentum Envelopes for Reaction Wheel Arrays

Science.gov (United States)

Markley, F. Landis; Reynolds, Reid G.; Liu, Frank X.; Lebsock, Kenneth L.

2009-01-01

Spacecraft reaction wheel maneuvers are limited by the maximum torque and/or angular momentum that the wheels can provide. For an n-wheel configuration, the torque or momentum envelope can be obtained by projecting the n-dimensional hypercube, representing the domain boundary of individual wheel torques or momenta, into three dimensional space via the 3xn matrix of wheel axes. In this paper, the properties of the projected hypercube are discussed, and algorithms are proposed for determining this maximal torque or momentum envelope for general wheel configurations. Practical strategies for distributing a prescribed torque or momentum among the n wheels are presented, with special emphasis on configurations of four, five, and six wheels.

Analysis of thrust/torque signature of MOV

International Nuclear Information System (INIS)

Ryu, Ho Geun; Park, Seong Keun; Kim, Dae Woong

2001-01-01

For the evaluation of operability of MOV(Motor Operated Valve), the precision prediction of thrust/torque acting on the valve is important. In this paper, the analytical prediction method of thrust/torque was proposed. The design basis stem thrust calculation typically considers the followings: packing thrust, stem rejection load, design basis differential pressure load. In general, test results show that temperature, pressure, fluid type, and differential pressure, independently and combination, all have an effect on the friction factor. The prediction results of thrust/torque are well agreement with dynamic test results

Corotation torques in the solar nebula - the cutoff function

International Nuclear Information System (INIS)

Ward, W.R.

1989-01-01

The behavior of high-order corotation resonances in a disk of finite thickness is examined. The torque exerted at an mth-order resonance is determined by employing a vertically averaged disturbing function, and the ratio of this torque to that exerted on a cold, two-dimensional disk is identified as the so-called torque cutoff function. This function is then used to calculate contributions from the corotation torques to eccentricity variations of a perturber's orbit assumed orbiting in the disk. 11 references

Towards Scalable Strain Gauge-Based Joint Torque Sensors

Science.gov (United States)

D’Imperio, Mariapaola; Cannella, Ferdinando; Caldwell, Darwin G.; Cuschieri, Alfred

2017-01-01

During recent decades, strain gauge-based joint torque sensors have been commonly used to provide high-fidelity torque measurements in robotics. Although measurement of joint torque/force is often required in engineering research and development, the gluing and wiring of strain gauges used as torque sensors pose difficulties during integration within the restricted space available in small joints. The problem is compounded by the need for a scalable geometric design to measure joint torque. In this communication, we describe a novel design of a strain gauge-based mono-axial torque sensor referred to as square-cut torque sensor (SCTS), the significant features of which are high degree of linearity, symmetry, and high scalability in terms of both size and measuring range. Most importantly, SCTS provides easy access for gluing and wiring of the strain gauges on sensor surface despite the limited available space. We demonstrated that the SCTS was better in terms of symmetry (clockwise and counterclockwise rotation) and more linear. These capabilities have been shown through finite element modeling (ANSYS) confirmed by observed data obtained by load testing experiments. The high performance of SCTS was confirmed by studies involving changes in size, material and/or wings width and thickness. Finally, we demonstrated that the SCTS can be successfully implementation inside the hip joints of miniaturized hydraulically actuated quadruped robot-MiniHyQ. This communication is based on work presented at the 18th International Conference on Climbing and Walking Robots (CLAWAR). PMID:28820446

Technical Errors May Affect Accuracy of Torque Limiter in Locking Plate Osteosynthesis.

Science.gov (United States)

Savin, David D; Lee, Simon; Bohnenkamp, Frank C; Pastor, Andrew; Garapati, Rajeev; Goldberg, Benjamin A

2016-01-01

In locking plate osteosynthesis, proper surgical technique is crucial in reducing potential pitfalls, and use of a torque limiter makes it possible to control insertion torque. We conducted a study of the ways in which different techniques can alter the accuracy of torque limiters. We tested 22 torque limiters (1.5 Nm) for accuracy using hand and power tools under different rotational scenarios: hand power at low and high velocity and drill power at low and high velocity. We recorded the maximum torque reached after each torque-limiting event. Use of torque limiters under hand power at low velocity and high velocity resulted in significantly (P torque and subsequent complications. For torque limiters, the most reliable technique involves hand power at slow velocity or drill power with careful control of insertion speed until 1 torque-limiting event occurs.

Calculation of Cogging Torque in Hybrid Stepping Motors | Agber ...

African Journals Online (AJOL)

When the windings of a hybrid stepping motor are unexcited the permanent magnet's flux produces cogging torque. This torque has both desirable and undesirable features depending on the application that the motor is put into. This paper formulates an analytical method for predicting cogging torque using measured ...

Remote calibration of torque wrenches in a hostile environment

Science.gov (United States)

Griffin, D. M.

1982-03-01

A relatively simple device is described which provides the capability for remote comparison of torque wrenches over a limited range. The device, properly used, provides calibration capability for most inch pound and foot pound range torque wrenches. For purposes of this discussion, the device itself was developed specifically for adapting an existing torque measuring system with torque wrenches in hostile environment. A gloved access port is utilized to manipulate the fixture while a viewing window and mirror are used to make visual comparisons. Click type wrenches do not require use of the mirror.

Advanced single tooth torquing plier with high precision: A clinical innovation

Directory of Open Access Journals (Sweden)

Jitendra Raghuwanshi

2017-01-01

Full Text Available Torque is the force which gives the operator control over the movements of roots of teeth in bilateral direction. There are various pliers available to apply torque in individual tooth, but none of the pliers are capable of measuring accurately the degrees of torque incorporated, so we have attempted to make a modified torquing plier to incorporate and measure the degrees of incorporated torque precisely.

Influência da preocupação com quedas na mobilidade e na força de reação do solo em idosas durante descida de escada = Influence of concern about falls in mobility and ground reaction force in elderly women's during stairs descent

Directory of Open Access Journals (Sweden)

Silva, Danilo de Oliveira

2014-01-01

Conclusões: Idosas com preocupação com queda apresentaram menor desempenho no teste funcional do que idosas com ausência dessa preocupação. Entretanto, não houve diferença entre os grupos quanto à variável cinética

Torque-onset determination: Unintended consequences of the threshold method.

Science.gov (United States)

Dotan, Raffy; Jenkins, Glenn; O'Brien, Thomas D; Hansen, Steve; Falk, Bareket

2016-12-01

Compared with visual torque-onset-detection (TOD), threshold-based TOD produces onset bias, which increases with lower torques or rates of torque development (RTD). To compare the effects of differential TOD-bias on common contractile parameters in two torque-disparate groups. Fifteen boys and 12 men performed maximal, explosive, isometric knee-extensions. Torque and EMG were recorded for each contraction. Best contractions were selected by peak torque (MVC) and peak RTD. Visual-TOD-based torque-time traces, electromechanical delays (EMD), and times to peak RTD (tRTD) were compared with corresponding data derived from fixed 4-Nm- and relative 5%MVC-thresholds. The 5%MVC TOD-biases were similar for boys and men, but the corresponding 4-Nm-based biases were markedly different (40.3±14.1 vs. 18.4±7.1ms, respectively; ptorque kinetics tended to be faster than the boys' (NS), but the 4-Nm-based kinetics erroneously depicted the boys as being much faster to any given %MVC (p<0.001). When comparing contractile properties of dissimilar groups, e.g., children vs. adults, threshold-based TOD methods can misrepresent reality and lead to erroneous conclusions. Relative-thresholds (e.g., 5% MVC) still introduce error, but group-comparisons are not confounded. Copyright © 2016 Elsevier Ltd. All rights reserved.

Direct Torque Control of Matrix Converter Fed Induction Motor Drive

Directory of Open Access Journals (Sweden)

JAGADEESAN Karpagam

2011-10-01

Full Text Available This paper presents the Direct TorqueControl (DTC of induction motor drive using matrixconverters. DTC is a high performance motor controlscheme with fast torque and flux responses. However,the main disadvantage of conventional DTC iselectromagnetic torque ripple. In this paper, directtorque control for Induction Motors using MatrixConverters is analysed and points out the problem ofthe electromagnetic torque ripple which is one of themost important drawbacks of the Direct TorqueControl. Besides, the matrix converter is a single-stageac-ac power conversion device without dc-link energystorage elements. Matrix converter (MC may becomea good alternative to voltage-source inverter (VSI.This work combines the advantages of the matrixconverter with those of the DTC technique, generatingthe required voltage vectors under unity input powerfactor operation. Simulation results demonstrates theeffectiveness of the torque control.

Diffusion of torqued active particles

Science.gov (United States)

Sandoval, Mario; Lauga, Eric

2012-11-01

Motivated by swimming microorganisms whose trajectories are affected by the presence of an external torque, we calculate the diffusivity of an active particle subject to an external torque and in a fluctuating environment. The analytical results are compared with Brownian dynamics simulations showing excellent agreement between theory and numerical experiments. This work was funded in part by the Consejo Nacional de Ciencia y Tecnologia of Mexico (Conacyt postdoctoral fellowship to M. S.) and the US National Science Foundation (Grant CBET-0746285 to E.L.).

Application of Space Vector Modulation in Direct Torque Control of PMSM

Directory of Open Access Journals (Sweden)

Michal Malek

2008-01-01

Full Text Available The paper deals with an improvement of direct torque control method for permanent magnet synchronous motor drives. Electrical torque distortion of the machine under original direct torque control is relatively high and if proper measures are taken it can be substantially decreased. The proposed solution here is to combine direct torque control with the space vector modulation technique. Such approach can eliminate torque distortion while preserving the simplicity of the original method.

Dependencia funcional y bienestar en personas mayores institucionalizadas

Directory of Open Access Journals (Sweden)

María Teresa Rodríguez Díaz

2014-06-01

Full Text Available El presente estudio tiene como objetivo evaluar el bienestar emocional de las personas mayores de 60 años en relación al grado de dependencia funcional. Como indicadores del bienestar se evalúan los niveles de depresión (Yesavage y ansiedad (STAI-R, la satisfacción vital (CSV y la ansiedad ante la muerte (DAS. Se ha realizado un estudio descriptivo transversal en un grupo de personas mayores de 60 años (n=103. Los datos se han recogido usando cuestionarios estandarizados. Para el análisis de los datos se han utilizado correlaciones bivariadas entre las principales medidas, análisis univariado (ANOVA y la prueba de Bonferroni para comprobar las diferencias significativas entre los grupos (p< .05. Los resultados indican que se encuentran diferencias significativas entre los grupos de dependencia para la edad, deterioro cognitivo, depresión y ansiedad ante la muerte. En conclusión, se encuentra una relación directa entre el grado de dependencia funcional y el nivel de malestar emocional.

Intrinsic magnetic torque at low magnetic induction

International Nuclear Information System (INIS)

Doria, M.M.; Oliveira, I.G. de.

1993-01-01

Using anisotropic London theory the intrinsic magnetic torque for extreme type II uniaxial superconductors for any value of the magnetic induction is obtained. It is considered the vortex lines straight and take into account the contribution of the supercurrents flowing inside the vortex core within the London theory. It is shown that the interline and intra line free energies give opposite torque contributions, the first drives the magnetic induction parallel to the superconductor's axis of symmetry and the second orthogonal to it. At high magnetic induction torque expression obtained generalizes V. Kogan's formula since it has no free parameters other than the anisotropy γ = m 1 /m 3 and the Ginzburg-Landau parameter κ. At low magnetic induction it is proposed a way to observe vortex chains effects in the total torque based on the fact that London theory is linear and the energy to make a single vortex line in space is independent of the magnetic induction. (author)

Excitable particles in an optical torque wrench

Science.gov (United States)

Pedaci, Francesco; Huang, Zhuangxiong; van Oene, Maarten; Barland, Stephane; Dekker, Nynke H.

2011-03-01

The optical torque wrench is a laser trapping technique capable of applying and directly measuring torque on microscopic birefringent particles using spin momentum transfer, and has found application in the measurement of static torsional properties of biological molecules such as single DNAs. Motivated by the potential of the optical torque wrench to access the fast rotational dynamics of biological systems, a result of its all-optical manipulation and detection, we focus on the angular dynamics of the trapped birefringent particle, demonstrating its excitability in the vicinity of a critical point. This links the optical torque wrench to nonlinear dynamical systems such as neuronal and cardiovascular tissues, nonlinear optics and chemical reactions, all of which display an excitable binary (`all-or-none') response to input perturbations. On the basis of this dynamical feature, we devise and implement a conceptually new sensing technique capable of detecting single perturbation events with high signal-to-noise ratio and continuously adjustable sensitivity.

Low mass planet migration in magnetically torqued dead zones - II. Flow-locked and runaway migration, and a torque prescription

Science.gov (United States)

McNally, Colin P.; Nelson, Richard P.; Paardekooper, Sijme-Jan

2018-04-01

We examine the migration of low mass planets in laminar protoplanetary discs, threaded by large scale magnetic fields in the dead zone that drive radial gas flows. As shown in Paper I, a dynamical corotation torque arises due to the flow-induced asymmetric distortion of the corotation region and the evolving vortensity contrast between the librating horseshoe material and background disc flow. Using simulations of laminar torqued discs containing migrating planets, we demonstrate the existence of the four distinct migration regimes predicted in Paper I. In two regimes, the migration is approximately locked to the inward or outward radial gas flow, and in the other regimes the planet undergoes outward runaway migration that eventually settles to fast steady migration. In addition, we demonstrate torque and migration reversals induced by midplane magnetic stresses, with a bifurcation dependent on the disc surface density. We develop a model for fast migration, and show why the outward runaway saturates to a steady speed, and examine phenomenologically its termination due to changing local disc conditions. We also develop an analytical model for the corotation torque at late times that includes viscosity, for application to discs that sustain modest turbulence. Finally, we use the simulation results to develop torque prescriptions for inclusion in population synthesis models of planet formation.

Modified Direct Torque Control of Three-Phase Induction Motor Drives with Low Ripple in Flux and Torque

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Vinay KUMAR

2011-06-01

Full Text Available This paper proposes an algorithm for direct flux and torque controlled three phase induction motor drive systems. This method is based on control of slip speed and decoupled between amplitude and angle of reference stator flux for determining required stator voltage vector. In this proposes model, integrator unit is not required to generate the reference stator flux angle for calculating required stator voltage vector, hence it eliminates the initial values problems in real time. Within the given sampling time, flux as well as torque errors are controlled by stator voltage vector which is evaluated from reference stator flux. The direct torque control is achieved by reference stator flux angle which is generates from instantaneous slip speed angular frequency and stator flux angular frequency. The amplitude of the reference stator flux is kept constant at rated value. This technique gives better performance in three-phase induction motor than conventional technique. Simulation results for 3hp induction motor drive, for both proposed and conventional techniques, are presented and compared. From the results it is found that the stator current, flux linkage and torque ripples are decreased with proposed technique.

Spin-transfer torque in spin filter tunnel junctions

KAUST Repository

Ortiz Pauyac, Christian

2014-12-08

Spin-transfer torque in a class of magnetic tunnel junctions with noncollinear magnetizations, referred to as spin filter tunnel junctions, is studied within the tight-binding model using the nonequilibrium Green\\'s function technique within Keldysh formalism. These junctions consist of one ferromagnet (FM) adjacent to a magnetic insulator (MI) or two FM separated by a MI. We find that the presence of the magnetic insulator dramatically enhances the magnitude of the spin-torque components compared to conventional magnetic tunnel junctions. The fieldlike torque is driven by the spin-dependent reflection at the MI/FM interface, which results in a small reduction of its amplitude when an insulating spacer (S) is inserted to decouple MI and FM layers. Meanwhile, the dampinglike torque is dominated by the tunneling electrons that experience the lowest barrier height. We propose a device of the form FM/(S)/MI/(S)/FM that takes advantage of these characteristics and allows for tuning the spin-torque magnitudes over a wide range just by rotation of the magnetization of the insulating layer.

Eddy Current Sensing of Torque in Rotating Shafts

Science.gov (United States)

Varonis, Orestes J.; Ida, Nathan

2013-12-01

The noncontact torque sensing in machine shafts is addressed based on the stress induced in a press-fitted magnetoelastic sleeve on the shaft and eddy current sensing of the changes of electrical conductivity and magnetic permeability due to the presence of stress. The eddy current probe uses dual drive, dual sensing coils whose purpose is increased sensitivity to torque and decreased sensitivity to variations in distance between probe and shaft (liftoff). A mechanism of keeping the distance constant is also employed. Both the probe and the magnetoelastic sleeve are evaluated for performance using a standard eddy current instrument. An eddy current instrument is also used to drive the coils and analyze the torque data. The method and sensor described are general and adaptable to a variety of applications. The sensor is suitable for static and rotating shafts, is independent of shaft diameter and operational over a large range of torques. The torque sensor uses a differential eddy current measurement resulting in cancellation of common mode effects including temperature and vibrations.

Spin-transfer torque in spin filter tunnel junctions

KAUST Repository

Ortiz Pauyac, Christian; Kalitsov, Alan; Manchon, Aurelien; Chshiev, Mairbek

2014-01-01

Spin-transfer torque in a class of magnetic tunnel junctions with noncollinear magnetizations, referred to as spin filter tunnel junctions, is studied within the tight-binding model using the nonequilibrium Green's function technique within Keldysh formalism. These junctions consist of one ferromagnet (FM) adjacent to a magnetic insulator (MI) or two FM separated by a MI. We find that the presence of the magnetic insulator dramatically enhances the magnitude of the spin-torque components compared to conventional magnetic tunnel junctions. The fieldlike torque is driven by the spin-dependent reflection at the MI/FM interface, which results in a small reduction of its amplitude when an insulating spacer (S) is inserted to decouple MI and FM layers. Meanwhile, the dampinglike torque is dominated by the tunneling electrons that experience the lowest barrier height. We propose a device of the form FM/(S)/MI/(S)/FM that takes advantage of these characteristics and allows for tuning the spin-torque magnitudes over a wide range just by rotation of the magnetization of the insulating layer.

Cogging Torque Reduction Techniques for Spoke-type IPMSM

Science.gov (United States)

Bahrim, F. S.; Sulaiman, E.; Kumar, R.; Jusoh, L. I.

2017-08-01

A spoke-type interior permanent magnet synchronous motor (IPMSM) is extending its tentacles in industrial arena due to good flux-weakening capability and high power density. In many of the application, high strength of permanent magnet causes the undesirable effects of high cogging torque that can aggravate performance of the motor. High cogging torque is significantly produced by IPMSM due to the similar length and the effectiveness of the magnetic air-gap. The address of this study is to analyze and compare the cogging torque effect and performance of four common techniques for cogging torque reduction such as skewing, notching, pole pairing and rotor pole pairing. With the aid of 3-D finite element analysis (FEA) by JMAG software, a 6S-4P Spoke-type IPMSM with various rotor-PM configurations has been designed. As a result, the cogging torque effect reduced up to 69.5% for skewing technique, followed by 31.96%, 29.6%, and 17.53% by pole pairing, axial pole pairing and notching techniques respectively.

Standard practice for torque calibration of testing machines and devices

CERN Document Server

American Society for Testing and Materials. Philadelphia

2009-01-01

1.1 This practice covers procedures and requirements for the calibration of torque for static and quasi-static torque capable testing machines or devices. These may, or may not, have torque indicating systems and include those devices used for the calibration of hand torque tools. Testing machines may be calibrated by one of the three following methods or combination thereof: 1.1.1 Use of standard weights and lever arms. 1.1.2 Use of elastic torque measuring devices. 1.1.3 Use of elastic force measuring devices and lever arms. 1.1.4 Any of the methods require a specific uncertainty of measurement and a traceability derived from national standards of mass and length. 1.2 The procedures of 1.1.1, 1.1.2, and 1.1.3 apply to the calibration of the torque-indicating systems associated with the testing machine, such as a scale, dial, marked or unmarked recorder chart, digital display, etc. In all cases the buyer/owner/user must designate the torque-indicating system(s) to be calibrated and included in the repor...

Seguridad funcional de sensores de gas

OpenAIRE

Vega Remesal, Ángel; Medic Pejic, Ljiljana; Garcia Torrent, Javier

2013-01-01

La protección adecuada de los equipos o sistemas que han de trabajar en atmósferas potencialmente explosivas no es suficiente cuando se trata de la seguridad frente a posibles explosiones o a la prevención de potenciales riesgos directos de las personas, en cuyo caso deben estar amparados también por la llamada seguridad funcional que exige una serie de requisitos adicionales, cuya documentación debe proporcionar el fabricante de los equipos, junto con su manual de instrucciones.

Dynamics of domain wall driven by spin-transfer torque

International Nuclear Information System (INIS)

Chureemart, P.; Evans, R. F. L.; Chantrell, R. W.

2011-01-01

Spin-torque switching of magnetic devices offers new technological possibilities for data storage and integrated circuits. We have investigated domain-wall motion in a ferromagnetic thin film driven by a spin-polarized current using an atomistic spin model with a modified Landau-Lifshitz-Gilbert equation including the effect of the spin-transfer torque. The presence of the spin-transfer torque is shown to create an out-of-plane domain wall, in contrast to the external-field-driven case where an in-plane wall is found. We have investigated the effect of the spin torque on domain-wall displacement, domain-wall velocity, and domain-wall width, as well as the equilibration time in the presence of the spin-transfer torque. We have shown that the minimum spin-current density, regarded as the critical value for domain-wall motion, decreases with increasing temperature.

Processamento da rede neocognitron para reconhecimento facial em ambiente de alto desempenho GPU

OpenAIRE

Gustavo Poli Lameirão da Silva

2007-01-01

Neste trabalho é apresentada a implementação da Rede Neural Neocognitron, usando uma arquitetura de computação de alto desempenho baseada em GPU (Graphics Processing Unit). O Neocognitron é uma rede neural artificial, proposta por Fukushima e colaboradores, constituída de vários estágios de camadas de neurônios, organizados em matrizes bidimensionais denominadas planos celulares. Para o processamento de alto desempenho da aplicação de reconhecimento facial usando neocognitron foi utilizado o ...

A laserterapia de baixa potência melhora o desempenho muscular mensurado por dinamometria isocinética em humanos Low-level laser therapy enhances muscular performance as measured by isokinetic dynamometry in humans

Directory of Open Access Journals (Sweden)

Ernesto Cesar Pinto Leal Junior

2010-12-01

Full Text Available A fadiga muscular é uma nova área de pesquisa em laserterapia, com poucos estudos conduzidos. Embora a laserterapia de baixa potência (LBP previamente ao exercício tenha apresentado resultados positivos no retardo da fadiga musculoesquelética, ainda não foi estudada utilizando-se a dinamometria isocinética para mensurar desempenho e fadiga muscular. Este estudo tem o objetivo de avaliar os efeitos da LBP (655 nm, 50 mW, 2,4 J por ponto e 12 J de energia total sobre o desempenho e fadiga muscular do músculo tibial anterior, utilizando dinamometria isocinética (30 repetições de contração concêntrica em 14 indivíduos saudáveis sedentários do sexo masculino. Os voluntários foram avaliados ao efetuar 30 repetições isocinéticas de dorsiflexão de tornozelo à velocidade angular de 240°.seg-1. Os resultados mostram que, quando os voluntários foram tratados com LBP antes do exercício, os valores do pico de torque (30,91±5,86 N.m foram significativamente superiores, comparados a três medições anteriores sem a aplicação de LBP (24,92±7,45 N.m, pSkeletal muscle fatigue is a novel research area in laser therapy, there being few studies carried out. Though low-level laser therapy (LLLT applied prior to exercise has showed positive results in delaying skeletal muscle fatigue, no studies could be found that measured muscle performance and fatigue by means of isokinetic dynamometry. This clinical trial aims at assessing the effects of LLLT (655 nm, 50 mW and 12 J total energy delivered on anterior tibialis muscle performance and fatigue by means of isokinetic dynamometry (30 concentric-mode repetitions at 240º.sec-1 angular speed in 14 healthy male subjects. Results show that, when volunteers had been treated with LLLT prior to exercise, torque peak values (30.91±5.86 N.m were significantly higher than those of three previous measurements with no LLLT (24.92±7.45 N.m, p<0.001; 26.83±7.74 N.m, p<0.01; and 26.00±7.88 N.m, p<0

Drag and Torque on Locked Screw Propeller

Directory of Open Access Journals (Sweden)

Tomasz Tabaczek

2014-09-01

Full Text Available Few data on drag and torque on locked propeller towed in water are available in literature. Those data refer to propellers of specific geometry (number of blades, blade area, pitch and skew of blades. The estimation of drag and torque of an arbitrary propeller considered in analysis of ship resistance or propulsion is laborious. The authors collected and reviewed test data available in the literature. Based on collected data there were developed the empirical formulae for estimation of hydrodynamic drag and torque acting on locked screw propeller. Supplementary CFD computations were carried out in order to prove the applicability of the formulae to modern moderately skewed screw propellers.

Análise de desempenho dos investimentos sustentáveis no mercado acionário brasileiro

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Felipe Arias Fogliano de Souza Cunha

2014-06-01

Full Text Available Este trabalho estudou o Índice de Sustentabilidade Empresarial (ISE da Bolsa de Mercadorias e Futuros e Bolsa de Valores de São Paulo (BM&FBOVESPA, com o objetivo principal de analisar o desempenho histórico dos investimentos sustentáveis no mercado acionário brasileiro, considerando o período de dezembro de 2005 a dezembro de 2010. Foram utilizados, principalmente, os seguintes índices de desempenho: Sharpe, Treynor, Jensen, Sortino, Modigliani & Modigliani e Omega. Concluiu-se que, embora os investimentos sustentáveis tenham registrado características interessantes no mercado acionário brasileiro, tais como baixo risco diversificável e aumento de liquidez, não obtiveram, no período de análise, um desempenho financeiro satisfatório. À medida que a adoção de critérios que exijam elevado desempenho das empresas no que tange às questões sobre sustentabilidade se tornar obrigatória, esses investimentos tenderão à valorização.

Spin-Orbit Torques in Co/Pd Multilayer Nanowires

KAUST Repository

Jamali, Mahdi; Narayanapillai, Kulothungasagaran; Qiu, Xuepeng; Loong, Li Ming; Manchon, Aurelien; Yang, Hyunsoo

2013-01-01

Current induced spin-orbit torques have been studied in ferromagnetic nanowires made of 20 nm thick Co/Pd multilayers with perpendicular magnetic anisotropy. Using Hall voltage and lock-in measurements, it is found that upon injection of an electric current both in-plane (Slonczewski-like) and perpendicular (fieldlike) torques build up in the nanowire. The torque efficiencies are found to be as large as 1.17 and 5 kOe at 108  A/cm2 for the in-plane and perpendicular components, respectively, which is surprisingly comparable to previous studies in ultrathin (∼1  nm) magnetic bilayers. We show that this result cannot be explained solely by spin Hall effect induced torque at the outer interfaces, indicating a probable contribution of the bulk of the Co/Pd multilayer.

Spin-Orbit Torques in Co/Pd Multilayer Nanowires

KAUST Repository

Jamali, Mahdi

2013-12-09

Current induced spin-orbit torques have been studied in ferromagnetic nanowires made of 20 nm thick Co/Pd multilayers with perpendicular magnetic anisotropy. Using Hall voltage and lock-in measurements, it is found that upon injection of an electric current both in-plane (Slonczewski-like) and perpendicular (fieldlike) torques build up in the nanowire. The torque efficiencies are found to be as large as 1.17 and 5 kOe at 108  A/cm2 for the in-plane and perpendicular components, respectively, which is surprisingly comparable to previous studies in ultrathin (∼1  nm) magnetic bilayers. We show that this result cannot be explained solely by spin Hall effect induced torque at the outer interfaces, indicating a probable contribution of the bulk of the Co/Pd multilayer.

Desempenho organizacional e suas relações com competências gerenciais, suporte organizacional e treinamento

Directory of Open Access Journals (Sweden)

Hugo Pena Brandão

2012-12-01

Full Text Available Na pesquisa aqui relatada, objetivou-se verificar a existência de relações preditivas entre as competências expressas por gerentes de agências bancárias, a percepção deles sobre o suporte organizacional, o número de horas dedicadas por eles a treinamentos e o desempenho das agências em que atuam. Valeu-se de questionários estruturados para coleta de dados primários, sendo a amostra constituída por 186 gerentes de agências e 77 superintendentes regionais do Banco do Brasil. Utilizaram-se, também, dados secundários sobre o desempenho das agências em seis dimensões: resultado econômico, estratégia e operações, sociedade, clientes, processos e comportamento organizacional. Foram realizadas análises de regressão padrão para teste do modelo de investigação. As competências relativas à gestão estratégica e à gestão financeira revelaram-se preditoras de diferentes dimensões do desempenho das agências. Outras competências (gestão de processos e gestão socioambiental, o número de horas dedicadas a treinamentos e a percepção dos gestores acerca das práticas de gestão de desempenho da empresa (uma dimensão do suporte organizacional apresentaram efeitos menos abrangentes. Depois de isolados os efeitos de variáveis de controle, as variâncias explicadas pelos referidos preditores situaram-se entre 2,2% e 6,8%. Recaiu sobre o desempenho da agência na perspectiva clientes o menor percentual de explicação e sobre o desempenho nas perspectivas resultado econômico e estratégia e operações a maior variância explicada. Ao final, são discutidas implicações dos resultados e apresentadas recomendações práticas.

Current induced torques and interfacial spin-orbit coupling: Semiclassical modeling

KAUST Repository

Haney, Paul M.

2013-05-07

In bilayer nanowires consisting of a ferromagnetic layer and a nonmagnetic layer with strong spin-orbit coupling, currents create torques on the magnetization beyond those found in simple ferromagnetic nanowires. The resulting magnetic dynamics appear to require torques that can be separated into two terms, dampinglike and fieldlike. The dampinglike torque is typically derived from models describing the bulk spin Hall effect and the spin transfer torque, and the fieldlike torque is typically derived from a Rashba model describing interfacial spin-orbit coupling. We derive a model based on the Boltzmann equation that unifies these approaches. We also consider an approximation to the Boltzmann equation, the drift-diffusion model, that qualitatively reproduces the behavior, but quantitatively differs in some regimes. We show that the Boltzmann equation with physically reasonable parameters can match the torques for any particular sample, but in some cases, it fails to describe the experimentally observed thickness dependencies.

Spin-torque generation in topological insulator based heterostructures

KAUST Repository

Fischer, Mark H.; Vaezi, Abolhassan; Manchon, Aurelien; Kim, Eun-Ah

2016-01-01

Heterostructures utilizing topological insulators exhibit a remarkable spin-torque efficiency. However, the exact origin of the strong torque, in particular whether it stems from the spin-momentum locking of the topological surface states or rather

Robust spin transfer torque in antiferromagnetic tunnel junctions

KAUST Repository

Saidaoui, Hamed Ben Mohamed; Waintal, Xavier; Manchon, Aurelien

2017-01-01

We theoretically study the current-induced spin torque in antiferromagnetic tunnel junctions, composed of two semi-infinite antiferromagnetic layers separated by a tunnel barrier, in both clean and disordered regimes. We find that the torque

How joint torques affect hamstring injury risk in sprinting swing-stance transition.

Science.gov (United States)

Sun, Yuliang; Wei, Shutao; Zhong, Yunjian; Fu, Weijie; Li, Li; Liu, Yu

2015-02-01

The potential mechanisms of hamstring strain injuries in athletes are not well understood. The study, therefore, was aimed at understanding hamstring mechanics by studying loading conditions during maximum-effort overground sprinting. Three-dimensional kinematics and ground reaction force data were collected from eight elite male sprinters sprinting at their maximum effort. Maximal isometric torques of the hip and knee were also collected. Data from the sprinting gait cycle were analyzed via an intersegmental dynamics approach, and the different joint torque components were calculated. During the initial stance phase, the ground reaction force passed anteriorly to the knee and hip, producing an extension torque at the knee and a flexion torque at the hip joint. Thus, the active muscle torque functioned to produce flexion torque at the knee and extension torque at the hip. The maximal muscle torque at the knee joint was 1.4 times the maximal isometric knee flexion torque. During the late swing phase, the muscle torque counterbalanced the motion-dependent torque and acted to flex the knee joint and extend the hip joint. The loading conditions on the hamstring muscles were similar to those of the initial stance phase. During both the initial stance and late swing phases, the large passive torques at both the knee and hip joints acted to lengthen the hamstring muscles. The active muscle torques generated mainly by the hamstrings functioned to counteract those passive effects. As a result, during sprinting or high-speed locomotion, the hamstring muscles may be more susceptible to high risk of strain injury during these two phases.

Valley-dependent spin-orbit torques in two-dimensional hexagonal crystals

KAUST Repository

Li, Hang; Wang, Xuhui; Manchon, Aurelien

2016-01-01

We study spin-orbit torques in two-dimensional hexagonal crystals such as graphene, silicene, germanene, and stanene. The torque possesses two components, a fieldlike term due to inverse spin galvanic effect and an antidamping torque originating from Berry curvature in mixed spin-k space. In the presence of staggered potential and exchange field, the valley degeneracy can be lifted and we obtain a valley-dependent Berry curvature, leading to a tunable antidamping torque by controlling the valley degree of freedom. The valley imbalance can be as high as 100% by tuning the bias voltage or magnetization angle. These findings open new venues for the development of current-driven spin-orbit torques by structural design.

Valley-dependent spin-orbit torques in two-dimensional hexagonal crystals

KAUST Repository

Li, Hang

2016-01-11

We study spin-orbit torques in two-dimensional hexagonal crystals such as graphene, silicene, germanene, and stanene. The torque possesses two components, a fieldlike term due to inverse spin galvanic effect and an antidamping torque originating from Berry curvature in mixed spin-k space. In the presence of staggered potential and exchange field, the valley degeneracy can be lifted and we obtain a valley-dependent Berry curvature, leading to a tunable antidamping torque by controlling the valley degree of freedom. The valley imbalance can be as high as 100% by tuning the bias voltage or magnetization angle. These findings open new venues for the development of current-driven spin-orbit torques by structural design.

Desempenho motor em uma amostra de escolares brasileiros

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Dartagnan Pinto Guedes

2011-06-01

Full Text Available O estudo analisou o desempenho motor em relação à idade cronológica e ao sexo em amostra representativa de escolares de Montes Claros, Minas Gerais, Brasil. A amostra foi constituída por 2849 sujeitos (1457 raparigas e 1392 rapazes, com idades entre 6 e 18 anos, selecionada aleatoriamente. Os componentes de desempenho motor foram determinados a partir da bateria de teste envolvendo cinco itens: a sit-and-reach, b curl-ups, c trunk-lift, d push-ups e e PACER. Os resultados encontrados mostram que, em quase todos os testes motores administrados foram constatadas diferenças inter-sexos desde os 6 anos que aumentaram drasticamente a partir dos 12-13 anos. Em relação à idade cronológica, os rapazes na maioria dos testes motores administrados apresentaram gradualmente melhores resultados desde os 6 até os 18 anos, enquanto entre as raparigas os resultados mais elevados ocorreram por volta dos 11-12 anos com posterior declínio ou constância de seus escores.

Influência do consumo alimentar e uso de suplementos no desempenho de paratletas brasileiros

Directory of Open Access Journals (Sweden)

Renata Rangel Barboza

2015-10-01

Full Text Available RESUMOIntrodução:Atletas de halterofilismo buscam aumentar sua força em relação ao peso corporal utilizando treinamento resistido e a nutrição como ferramentas para melhorar o desempenho. Apesar dos benefícios proporcionados por um adequado planejamento alimentar, muitos atletas utilizam estratégias inadequadas, manifestadas pela piora na composição corporal e no desempenho esportivo.Objetivo:Analisar o consumo energético e proteico e o uso de suplementos alimentares de paratletas a fim de avaliar a influência da estratégia dietética no desempenho.Métodos:Foram coletados dados pessoais, medidas antropométricas, informações referentes ao comportamento alimentar e da competição de 24 paratletas halterofilistas do sexo masculino.Resultados:A quantidade de calorias e as porções de macronutrientes consumidas pela alimentação foram em média 2.235,8 ± 694,92 kcal, 27 ± 11,55% proteínas, 46 ± 8,17% carboidratos e 27 ± 8,57% lipídeos. Dos atletas estudados, 87,5% relataram utilizar suplementos alimentares. Os atletas com maior índice de massa corporal (IMC apresentaram menor ingestão energética e proteica relativa, maior somatório de dobras cutâneas e desempenho similar a dos demais estudados.Conclusão:A estratégia utilizada pelos atletas de maior massa corporal não propiciou melhoria direta no desempenho e influen-ciou negativamente na composição corporal. Este fato deve-se provavelmente à falta de adequação entre dieta e suplementação.

TDAH, funciones ejecutivas y atención

OpenAIRE

Amador, Juan Antonio; Krieger, Virginia Edith

2013-01-01

Este documento presenta las características del trastorno por déficit de atención con hiperactividad (TDAH), los síntomas y conductas alteradas asociadas al trastorno y los problemas más comunes de las personas con TDAH. También se describe el concepto de las funciones ejecutivas (FE), las relaciones entre TDAH y FE y algunas estrategias e instrumentos útiles para la evaluación de las FE.

Prevailing Torque Locking Feature in Threaded Fasteners Using Anaerobic Adhesive

Science.gov (United States)

Hernandez, Alan; Hess, Daniel P.

2016-01-01

This paper presents results from tests to assess the use of anaerobic adhesive for providing a prevailing torque locking feature in threaded fasteners. Test procedures are developed and tests are performed on three fastener materials, four anaerobic adhesives, and both unseated assembly conditions. Five to ten samples are tested for each combination. Tests for initial use, reuse without additional adhesive, and reuse with additional adhesive are performed for all samples. A 48-hour cure time was used for all initial use and reuse tests. Test data are presented as removal torque versus removal angle with the specification required prevailing torque range added for performance assessment. Percent specification pass rates for the all combinations of fastener material, adhesive, and assembly condition are tabulated and reveal use of anaerobic adhesive as a prevailing torque locking feature is viable. Although not every possible fastener material and anaerobic adhesive combination provides prevailing torque values within specification, any combination can be assessed using the test procedures presented. Reuse without additional anaerobic adhesive generally provides some prevailing torque, and in some cases within specification. Reuse with additional adhesive often provides comparable removal torque data as in initial use.

Manipulating the voltage dependence of tunneling spin torques

KAUST Repository

Manchon, Aurelien

2012-01-01

Voltage-driven spin transfer torques in magnetic tunnel junctions provide an outstanding tool to design advanced spin-based devices for memory and reprogrammable logic applications. The non-linear voltage dependence of the torque has a direct impact

Envelhecimento ativo e sua relação com a independência funcional

OpenAIRE

Ferreira,Olívia Galvão Lucena; Maciel,Silvana Carneiro; Costa,Sônia Maria Gusmão; Silva,Antonia Oliveira; Moreira,Maria Adelaide Silva Paredes

2012-01-01

El objetivo del presente estudio fue analizar los factores determinantes del envejecimiento activo y su relación con la independencia funcional. La investigación se realizó con 100 personas mayores de una Unidad de Salud de la Familia, en João Pessoa-PB, Brasil. Como instrumentos para la evaluación de personas mayores se utilizó la Medida de Independencia Funcional y un cuestionario sociodemográfico. Los datos fueron analizados a través del software SPSS. Según los resultados, todos los sujet...

Magnon-mediated Dzyaloshinskii-Moriya torque in homogeneous ferromagnets

KAUST Repository

Manchon, Aurelien; Ndiaye, Papa Birame; Moon, Jung-Hwan; Lee, Hyun-Woo; Lee, Kyung-Jin

2014-01-01

the time-averaged magnetization direction and display a number of similarities with the torques arising from the electron flow in a magnetic two-dimensional electron gas with Rashba spin-orbit coupling. This magnon-mediated spin-orbit torque can

Reconstruction of Twist Torque in Main Parachute Risers

Science.gov (United States)

Day, Joshua D.

2015-01-01

The reconstruction of twist torque in the Main Parachute Risers of the Capsule Parachute Assembly System (CPAS) has been successfully used to validate CPAS Model Memo conservative twist torque equations. Reconstruction of basic, one degree of freedom drop tests was used to create a functional process for the evaluation of more complex, rigid body simulation. The roll, pitch, and yaw of the body, the fly-out angles of the parachutes, and the relative location of the parachutes to the body are inputs to the torque simulation. The data collected by the Inertial Measurement Unit (IMU) was used to calculate the true torque. The simulation then used photogrammetric and IMU data as inputs into the Model Memo equations. The results were then compared to the true torque results to validate the Model Memo equations. The Model Memo parameters were based off of steel risers and the parameters will need to be re-evaluated for different materials. Photogrammetric data was found to be more accurate than the inertial data in accounting for the relative rotation between payload and cluster. The Model Memo equations were generally a good match and when not matching were generally conservative.

Hydrodynamic Torques and Rotations of Superparamagnetic Bead Dimers

Science.gov (United States)

Pease, Christopher; Etheridge, J.; Wijesinghe, H. S.; Pierce, C. J.; Prikockis, M. V.; Sooryakumar, R.

Chains of micro-magnetic particles are often rotated with external magnetic fields for many lab-on-a-chip technologies such as transporting beads or mixing fluids. These applications benefit from faster responses of the actuated particles. In a rotating magnetic field, the magnetization of superparamagnetic beads, created from embedded magnetic nano-particles within a polymer matrix, is largely characterized by induced dipoles mip along the direction of the field. In addition there is often a weak dipole mop that orients out-of-phase with the external rotating field. On a two-bead dimer, the simplest chain of beads, mop contributes a torque Γm in addition to the torque from mip. For dimers with beads unbound to each other, mop rotates individual beads which generate an additional hydrodynamic torque on the dimer. Whereas, mop directly torques bound dimers. Our results show that Γm significantly alters the average frequency-dependent dimer rotation rate for both bound and unbound monomers and, when mop exceeds a critical value, increases the maximum dimer rotation frequency. Models that include magnetic and hydrodynamics torques provide good agreement with the experimental findings over a range of field frequencies.

Torque control of underactuated tendon-driven fingers

Directory of Open Access Journals (Sweden)

M. E. Abdallah

2011-02-01

Full Text Available Given an underactuated tendon-driven finger, the finger posture is underdetermined and can move freely ("flop" in a region of slack tendons. This work shows that such an underactuated finger can be operated in tendon force control (rather than position control with effective performance. The force control eliminates the indeterminate slack while commanding a parameterized space of desired torques. The torque will either push the finger to the joint limits or wrap around an external object with variable torque – behavior that is sufficient for primarily gripping fingers. In addition, introducing asymmetric joint radii to the design allows the finger to command an expanded range of joint torques and to scan an expanded set of external surfaces. This study is motivated by the design and control of the secondary fingers of the NASA-GM R2 humanoid hand.

This paper was presented at the IFToMM/ASME International Workshop on Underactuated Grasping (UG2010, 19 August 2010, Montréal, Canada.

Influencia del nivel y de la actividad escolar en las funciones ejecutivas

Directory of Open Access Journals (Sweden)

Julio César Flores Lázaro

2011-01-01

Full Text Available El efecto de la escolaridad sobre el desempeño neuropsicológico ha sido ampliamente descrito excepto para las pruebas de funciones ejecutivas. En la actualidad más del 70% de la población mundial presenta un nivel educativo medio-bajo, por lo que es indispensable contar con el conocimiento sobre las características de desempeño en pruebas de funciones ejecutivas en este tipo de población; de forma que se pueda conocer y comprender sus características cognitivas. En este trabajo se analizó el efecto del nivel educativo y el tipo de actividad (escolar vs no escolar en una muestra de 83 participantes divididos en tres grupos: jóvenes con 11 años de escolaridad, adolescentes cursando el bachillerato, y jóvenes universitarios; sobre el desempeño en una amplia batería neuropsicológica de funciones ejecutivas. Los resultados muestran que la actividad escolar más que el nivel educativo es la principal variable que produce diferencias con los participantes jóvenes que ya no realizan su principal actividad en un contexto escolarizado.

How Joint Torques Affect Hamstring Injury Risk in Sprinting Swing–Stance Transition

Science.gov (United States)

SUN, YULIANG; WEI, SHUTAO; ZHONG, YUNJIAN; FU, WEIJIE; LI, LI; LIU, YU

2015-01-01

ABSTRACT Purpose The potential mechanisms of hamstring strain injuries in athletes are not well understood. The study, therefore, was aimed at understanding hamstring mechanics by studying loading conditions during maximum-effort overground sprinting. Methods Three-dimensional kinematics and ground reaction force data were collected from eight elite male sprinters sprinting at their maximum effort. Maximal isometric torques of the hip and knee were also collected. Data from the sprinting gait cycle were analyzed via an intersegmental dynamics approach, and the different joint torque components were calculated. Results During the initial stance phase, the ground reaction force passed anteriorly to the knee and hip, producing an extension torque at the knee and a flexion torque at the hip joint. Thus, the active muscle torque functioned to produce flexion torque at the knee and extension torque at the hip. The maximal muscle torque at the knee joint was 1.4 times the maximal isometric knee flexion torque. During the late swing phase, the muscle torque counterbalanced the motion-dependent torque and acted to flex the knee joint and extend the hip joint. The loading conditions on the hamstring muscles were similar to those of the initial stance phase. Conclusions During both the initial stance and late swing phases, the large passive torques at both the knee and hip joints acted to lengthen the hamstring muscles. The active muscle torques generated mainly by the hamstrings functioned to counteract those passive effects. As a result, during sprinting or high-speed locomotion, the hamstring muscles may be more susceptible to high risk of strain injury during these two phases. PMID:24911288

High torque DC motor fabrication and test program

Science.gov (United States)

Makus, P.

1976-01-01

The testing of a standard iron and standard alnico permanent magnet two-phase, brushless dc spin motor for potential application to the space telescope has been concluded. The purpose of this study was to determine spin motor power losses, magnetic drag, efficiency and torque speed characteristics of a high torque dc motor. The motor was designed and built to fit an existing reaction wheel as a test vehicle and to use existing brass-board commutation and torque command electronics. The results of the tests are included in this report.

Predictive torque and flux control of an induction machine drive ...

Indian Academy of Sciences (India)

Finite-state model predictive control; fuzzy decision making; multi-objective optimization; predictive torque control. Abstract. Among the numerous direct torque control techniques, the finite-state predictive torque control (FS-PTC) has emerged as a powerful alternative as it offers the fast dynamic response and the flexibility to ...

Electrode position markedly affects knee torque in tetanic, stimulated contractions.

Science.gov (United States)

Vieira, Taian M; Potenza, Paolo; Gastaldi, Laura; Botter, Alberto

2016-02-01

The purpose of this study was to investigate how much the distance between stimulation electrodes affects the knee extension torque in tetanic, electrically elicited contractions. Current pulses of progressively larger amplitude, from 0 mA to maximally tolerated intensities, were delivered at 20 pps to the vastus medialis, rectus femoris and vastus lateralis muscles of ten, healthy male subjects. Four inter-electrode distances were tested: 32.5% (L1), 45.0% (L2), 57.5% (L3) and 70% (L4) of the distance between the patella apex and the anterior superior iliac spine. The maximal knee extension torque and the current leading to the maximal torque were measured and compared between electrode configurations. The maximal current tolerated by each participant ranged from 60 to 100 mA and did not depend on the inter-electrode distance. The maximal knee extension torque elicited did not differ between L3 and L4 (P = 0.15) but, for both conditions, knee torque was significantly greater than for L1 and L2 (P torque elicited for L3 and L4 was two to three times greater than that obtained for L1 and L2. The current leading to maximal torque was not as sensitive to inter-electrode distance. Except for L1 current intensity did not change with electrode configuration (P > 0.16). Key results presented here revealed that for a given stimulation intensity, knee extension torque increased dramatically with the distance between electrodes. The distance between electrodes seems therefore to critically affect knee torque, with potential implication for optimising exercise protocols based on electrical stimulation.

Towards measuring quantum electrodynamic torque with a levitated nanorod

Science.gov (United States)

Xu, Zhujing; Bang, Jaehoon; Ahn, Jonghoon; Hoang, Thai M.; Li, Tongcang

2017-04-01

According to quantum electrodynamics, quantum fluctuations of electromagnetic fields give rise to a zero-point energy that never vanishes, even in the absence of electromagnetic sources. The interaction energy will not only lead to the well-known Casimir force but will also contribute to the Casimir torque for anisotropic materials. We propose to use an optically levitated nanorod in vacuum and a birefringent substrate to experimentally investigate the QED torque. We have previously observed the libration of an optically levitated non-spherical nanoparticle in vacuum and found it to be an ultrasensitive torque sensor. A nanorod with a long axis of 300nm and a diameter of 60nm levitated in vacuum at 10 (- 8) torr will have a remarkable torque detection sensitivity on the order of 10 (- 28) Nm/ √Hz, which will be sufficient to detect the Casimir torque. This work is partially supported by the National Science Foundation under Grant No.1555035-PHY.

Filogenia y desarrollo de funciones ejecutivas/ Phylogeny and executive functions development

Directory of Open Access Journals (Sweden)

Diego Alejandro Calle Sandoval

2017-06-01

Full Text Available El presente documento reflexiona acerca del valor filogenético que tiene para la especie humana el desarrollo de la corteza prefrontal y las funciones ejecutivas. Dicho análisis parte de la revisión de estudios empíricos sobre la génesis de estas en la infancia y la patología de las mismas durante el desarrollo, así como de las evidencias etológicas y paleoantropológicas del proceso de hominización. Igualmente, se discute en el artículo la forma como estas funciones neuropsicológicas le permiten al homo sapiens compensar su carácter biológico de inmadurez y falta de especialidades anatómicas.

Direct shaft torque measurements in a transient turbine facility

International Nuclear Information System (INIS)

Beard, Paul F; Povey, Thomas

2011-01-01

This paper describes the development and implementation of a shaft torque measurement system for the Oxford Turbine Research Facility (formerly the Turbine Test Facility (TTF) at QinetiQ, Farnborough), or OTRF. As part of the recent EU TATEF II programme, the facility was upgraded to allow turbine efficiency measurements to be performed. A shaft torque measurement system was developed as part of this upgrade. The system is unique in that, to the authors' knowledge, it provided the first direct measurement of shaft torque in a transient turbine facility although the system has wider applicability to rotating test facilities in which power measurement is a requirement. The adopted approach removes the requirement to quantify bearing friction, which can be difficult to accurately calibrate under representative operating conditions. The OTRF is a short duration (approximately 0.4 s run time) isentropic light-piston facility capable of matching all of the non-dimensional parameters important for aerodynamic and heat studies, namely Mach number, Reynolds number, non-dimensional speed, stage pressure ratio and gas-to-wall temperature ratio. The single-stage MT1 turbine used for this study is a highly loaded unshrouded design, and as such is relevant to modern military, or future civil aero-engine design. Shaft torque was measured directly using a custom-built strain gauge-based torque measurement system in the rotating frame of reference. This paper describes the development of this measurement system. The system was calibrated, including the effects of temperature, to a traceable primary standard using a purpose-built facility. The bias and precision uncertainties of the measured torque were ±0.117% and ±0.183%, respectively. To accurately determine the shaft torque developed by a turbine in the OTRF, small corrections due to inertial torque (associated with changes in the rotational speed) and aerodynamic drag (windage) are required. The methods for performing these

Heat Control via Torque Control in Friction Stir Welding

Science.gov (United States)

Venable, Richard; Colligan, Kevin; Knapp, Alan

2004-01-01

In a proposed advance in friction stir welding, the torque exerted on the workpiece by the friction stir pin would be measured and controlled in an effort to measure and control the total heat input to the workpiece. The total heat input to the workpiece is an important parameter of any welding process (fusion or friction stir welding). In fusion welding, measurement and control of heat input is a difficult problem. However, in friction stir welding, the basic principle of operation affords the potential of a straightforward solution: Neglecting thermal losses through the pin and the spindle that supports it, the rate of heat input to the workpiece is the product of the torque and the speed of rotation of the friction stir weld pin and, hence, of the spindle. Therefore, if one acquires and suitably processes data on torque and rotation and controls the torque, the rotation, or both, one should be able to control the heat input into the workpiece. In conventional practice in friction stir welding, one uses feedback control of the spindle motor to maintain a constant speed of rotation. According to the proposal, one would not maintain a constant speed of rotation: Instead, one would use feedback control to maintain a constant torque and would measure the speed of rotation while allowing it to vary. The torque exerted on the workpiece would be estimated as the product of (1) the torque-multiplication ratio of the spindle belt and/or gear drive, (2) the force measured by a load cell mechanically coupled to the spindle motor, and (3) the moment arm of the load cell. Hence, the output of the load cell would be used as a feedback signal for controlling the torque (see figure).

Classificador Neuro-nebuloso de Desempenho Escolar Usando o ANFIS com Implementação em R

Directory of Open Access Journals (Sweden)

Jeferson Costa da Silva

2015-11-01

Full Text Available Este artigo descreve alguns conceitos fundamentais para a implementação de um classificador neuro-nebuloso de desempenho escolar. Classificar informações de desempenho escolar é uma tarefa não-linear, pois envolve valores ("Atributos" como: nota, porcentagem de assiduidade (pontualidade e número de reprovações dos alunos em uma disciplina. O objetivo é qualificar o desempenho dos alunos em conceitos nebulosos ("Classes Nebulosas" como: ruim, bom ou ótimo. Baseado em informações numéricas contidas em um Dataset com os valores dos atributos é desenvolvido um classificador nebuloso baseado no modelo de ANFIS de aprendizagem e classificação neuro-nebulosa e implementado na linguagem de programação estatística R.

Análise do método de simulação de desempenho térmico da norma NBR 15.575

Directory of Open Access Journals (Sweden)

Márcio José SORGATO

2014-09-01

Full Text Available As normas de desempenho de edificações avaliam e regulamentam o setor da construção civil, garantindo um padrão mínimo de qualidade e desempenho das edificações residenciais. O artigo tem como objetivo avaliar o método de simulação do desempenho térmico de edificações residenciais da NBR 15575. Observou-se que o método da norma apresenta limitações, avaliando o desempenho da edificação através de dias típicos de verão e inverno. Como proposta, foi desenvolvido e encaminhado um novo método de simulação durante a consulta pública da NBR 15575. A proposta do novo método busca avaliar o desempenho térmico da edificação através dos graus-hora de resfriamento e aquecimento. Os resultados da comparação entre estes dois métodos foram analisados, permitindo observar que o método de simulação da NBR 15575 atende ao desempenho térmico mínimo quando comparado com o sistema construtivo com paredes de concreto de 5 cm de espessura. Já com a aplicação do método proposto, observou-se que a edificação apresentou um desempenho térmico insatisfatório para o sistema construtivo analisado. Palavras-Chave: simulação computacional, desempenho térmico, edificações residências.

Externalización De Funciones: Algunas Reflexiones Teóricas

Directory of Open Access Journals (Sweden)

Francisco Ganga Contreras

2008-04-01

También se aborda el origen del outsourcing, algunas diferencias conceptuales, sus principales ventajas y riesgos, además de incluir una revisión a la situación actual de la externalización de funciones en Chile.

A influência do desempenho motor no “status” social percebido por crianças

Directory of Open Access Journals (Sweden)

Pâmella MEDEIROS

Full Text Available Resumo Este estudo teve como objetivos descrever o desempenho motor de crianças e adolescentes em relação ao “status” social dos mesmos segundo a percepção dos colegas nos diferentes sexos, além de verificar se há o efeito sexo nessa possível associação. Participaram desta pesquisa 300 crianças e adolescentes do 3º ao 5º ano e da 4a a 6a série do Ensino Fundamental de duas escolas públicas, com idades entre oito e 14 anos. Os instrumentos utilizados foram a Bateria motora TGMD-2 e a Escala Subjetiva de Status Social. As meninas apresentaram melhor desempenho motor que os meninos, no entanto, apenas os meninos com melhor desempenho motor também apresentaram maior “status” social percebido. Tal situação nos indica que os meninos estão mais suscetíveis a avaliações sociais positivas pautadas em competências físicas que as meninas, podendo fazer uso do seu melhor nível de desempenho motor para elevar a sua popularidade na escola através de práticas esportivas.

Consciência fonológica e desempenho escolar Phonological awareness and school performance

Directory of Open Access Journals (Sweden)

Patrícia Aparecida Zuanetti

2008-01-01

Full Text Available OBJETIVOS: verificar a relação entre consciência fonológica e o desempenho acadêmico de escolares, e averiguar se a ordem de preferência para as tarefas acadêmicas é a mesma ordem conseguida por esta criança em seu desempenho. MÉTODOS: avaliou-se 24 crianças de uma sala da 2ª série do ensino fundamental de uma escola pública, aplicando a prova de consciência fonológica por produção oral e o teste de desempenho escolar. Excluíram-se todos os alunos que apresentavam distúrbios fonológicos. RESULTADOS: existe associação entre ordem de preferência e resultado apenas nas tarefas de aritmética e escrita, já na leitura não existe. Em relação ao desempenho nas tarefas de consciência fonológica, o grupo com desempenho escolar médio foi mais hábil em tarefas que envolviam síntese fonêmica, rima, segmentação fonêmica e manipulação fonêmica quando comparados aos alunos com desempenho acadêmico inferior. Quanto à correlação, esta foi positiva e forte entre as variáveis estudadas (consciência fonológica, desempenho escolar, leitura, escrita e aritmética. CONCLUSÕES: quanto mais desenvolvida é a consciência fonológica, melhor é a performance do aluno; Tarefas de rima, síntese, segmentação e manipulação fonêmica estão mais relacionadas à alfabetização. Existe associação entre ordem de preferência e resultado nas tarefas de aritmética e escrita.PURPOSE: to know the relationship between students’ phonological awareness and their school performance, and to study if the students preference order or school subjects agree with their performance order obtained in the tests. METHODS: 24 children in second degree of the public fundamental school was analyzed. They made a oral phonological awareness test and the school performance test. Every student with phonological disturbs was excluded from the study. RESULTS: we observed that there is an association between preference and performance orders just

Anomalous magnetic torque in the heavy-fermion superconductor UBe13

International Nuclear Information System (INIS)

Schmiedeshoff, G.M.; Fisk, Z.; Smith, J.L.

1994-01-01

Measurements of the magnetic torque acting upon a single crystal of the heavy-fermion superconductor UBe 13 have been made at temperatures from 0.5 K to 30.0 K and in magnetic fields to 23 T using a capacitive magnetometer. We find that a large, anomalous contribution to the magnetic torque appears in at low temperatures and in high fields. The anomalous torque coexists with the superconducting state at low temperature. We propose that the anomalous torque reflects the existence of a field-induced magnetic phase transition. (orig.)

Smooth torque speed characteristic of switched reluctance motors

DEFF Research Database (Denmark)

Zeng, Hui; Chen, Zhe; Chen, Hao

2014-01-01

The torque ripple of switched reluctance motors (SRMs) is the main disadvantage that limits the industrial application of these motors. Although several methods for smooth-toque operation (STO) have been proposed, STO works well only within a certain torque and speed range because...

Spin-transfer torque in tunnel junctions with ferromagnetic layer of finite thickness

International Nuclear Information System (INIS)

Wilczynski, M.

2011-01-01

Two components of the spin torque exerted on a free ferromagnetic layer of finite thickness and a half-infinite ferromagnetic electrode in single tunnel junctions have been calculated in the spin-polarized free-electron-like one-band model. It has been found that the torque oscillates with the thickness of ferromagnetic layer and can be enhanced in the junction with the special layer thickness. The bias dependence of torque components also significantly changes with layer thickness. It is non-symmetric for the normal torque, in contrast to the symmetric junctions with two identical half-infinite ferromagnetic electrodes. The asymmetry of the bias dependence of the normal component of the torque can be also observed in the junctions with different spin splitting of the electron bands in the ferromagnetic electrodes. - Research highlights: → The torque oscillates with the thickness of ferromagnetic layer. → Bias dependence of the torque changes with the layer thickness. → Bias dependence of the normal torque can be asymmetric.

Spin transfer torque in antiferromagnetic spin valves: From clean to disordered regimes

KAUST Repository

Saidaoui, Hamed Ben Mohamed; Manchon, Aurelien; Waintal, Xavier

2014-01-01

Current-driven spin torques in metallic spin valves composed of antiferromagnets are theoretically studied using the nonequilibrium Green's function method implemented on a tight-binding model. We focus our attention on G-type and L-type antiferromagnets in both clean and disordered regimes. In such structures, spin torques can either rotate the magnetic order parameter coherently (coherent torque) or compete with the internal antiferromagnetic exchange (exchange torque). We show that, depending on the symmetry of the spin valve, the coherent and exchange torques can either be in the plane, ∝n×(q×n) or out of the plane ∝n×q, where q and n are the directions of the order parameter of the polarizer and the free antiferromagnetic layers, respectively. Although disorder conserves the symmetry of the torques, it strongly reduces the torque magnitude, pointing out the need for momentum conservation to ensure strong spin torque in antiferromagnetic spin valves.

Spin transfer torque in antiferromagnetic spin valves: From clean to disordered regimes

KAUST Repository

Saidaoui, Hamed Ben Mohamed

2014-05-28

Current-driven spin torques in metallic spin valves composed of antiferromagnets are theoretically studied using the nonequilibrium Green\\'s function method implemented on a tight-binding model. We focus our attention on G-type and L-type antiferromagnets in both clean and disordered regimes. In such structures, spin torques can either rotate the magnetic order parameter coherently (coherent torque) or compete with the internal antiferromagnetic exchange (exchange torque). We show that, depending on the symmetry of the spin valve, the coherent and exchange torques can either be in the plane, ∝n×(q×n) or out of the plane ∝n×q, where q and n are the directions of the order parameter of the polarizer and the free antiferromagnetic layers, respectively. Although disorder conserves the symmetry of the torques, it strongly reduces the torque magnitude, pointing out the need for momentum conservation to ensure strong spin torque in antiferromagnetic spin valves.

Design of digital load torque observer in hybrid electric vehicle

Science.gov (United States)

Sun, Yukun; Zhang, Haoming; Wang, Yinghai

2008-12-01

In hybrid electric vehicle, engine begain to work only when motor was in high speed in order to decrease tail gas emission. However, permanent magnet motor was sensitive to its load, adding engine to the system always made its speed drop sharply, which caused engine to work in low efficiency again and produced much more environment pollution. Dynamic load torque model of permanent magnet synchronous motor is established on the basic of motor mechanical equation and permanent magnet synchronous motor vector control theory, Full- digital load torque observer and compensation control system is made based on TMS320F2407A. Experiment results prove load torque observer and compensation control system can detect and compensate torque disturbing effectively, which can solve load torque disturbing and decrease gas pollution of hybrid electric vehicle.

Four-bar linkage-based automatic tool changer: Dynamic modeling and torque optimization

International Nuclear Information System (INIS)

Lee, Sangho; Seo, TaeWon; Kim, Jong-Won; Kim, Jongwon

2017-01-01

An Automatic tool changer (ATC) is a device used in a tapping machine to reduce process time. This paper presents the optimization of a Peak torque reduction mechanism (PTRM) for an ATC. It is necessary to reduce the fatigue load and energy consumed, which is related to the peak torque. The PTRM uses a torsion spring to reduce the peak torque and was applied to a novel ATC mechanism, which was modeled using inverse dynamics. Optimization of the PTRM is required to minimize the peak torque. The design parameters are the initial angle and stiffness of the torsion spring, and the objective function is the peak torque of the input link. The torque was simulated, and the peak torque was decreased by 10 %. The energy consumed was reduced by the optimization.

Four-bar linkage-based automatic tool changer: Dynamic modeling and torque optimization

Energy Technology Data Exchange (ETDEWEB)

Lee, Sangho; Seo, TaeWon [Yeungnam University, Gyeongsan (Korea, Republic of); Kim, Jong-Won; Kim, Jongwon [Seoul National University, Seoul (Korea, Republic of)

2017-05-15

An Automatic tool changer (ATC) is a device used in a tapping machine to reduce process time. This paper presents the optimization of a Peak torque reduction mechanism (PTRM) for an ATC. It is necessary to reduce the fatigue load and energy consumed, which is related to the peak torque. The PTRM uses a torsion spring to reduce the peak torque and was applied to a novel ATC mechanism, which was modeled using inverse dynamics. Optimization of the PTRM is required to minimize the peak torque. The design parameters are the initial angle and stiffness of the torsion spring, and the objective function is the peak torque of the input link. The torque was simulated, and the peak torque was decreased by 10 %. The energy consumed was reduced by the optimization.

KNEE ISOKINETIC TORQUE IMBALANCE IN FEMALE FUTSAL PLAYERS

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Ana Carolina de Mello Alves Rodrigues

Full Text Available ABSTRACT Introduction: The specificity of sports training can lead to muscle specialization with a possible change in the natural hamstring/quadriceps torque ratio (HQ ratio, constituting a risk factor for muscle injury at the joint angles in which muscle imbalance may impair dynamic stability. Objective: The aim was to evaluate the torque distribution of the hamstrings and quadriceps and the HQ ratio throughout the range of motion in order to identify possible muscle imbalances at the knee of female futsal athletes. Methods: Nineteen amateur female futsal athletes had their dominant limb HQ ratio evaluated in a series of five maximum repetitions of flexion/extension of the knee at 180°/second in the total joint range of motion (30° to 80°. The peak flexor and extensor torque and the HQ ratio (% were compared each 5° of knee motion using one-way repeated measures ANOVA and Tukey’s post hoc test (p<0.05 to determine the joint angles that present muscular imbalance. Results: Quadriceps torque was higher than 50° to 60° of knee flexion, while hamstrings torque was higher than 55° to 65°. The HQ ratio presented lower values than 30° to 45° of knee flexion and four athletes presented values lower than 60%, which may represent a risk of injury. However, the HQ ratio calculated by the peak torque showed only one athlete with less than 60%. Conclusion: The HQ ratio analyzed throughout the knee range of motion allowed identifying muscle imbalance at specific joint angles in female futsal players.

Analyzing the installation angle error of a SAW torque sensor

International Nuclear Information System (INIS)

Fan, Yanping; Ji, Xiaojun; Cai, Ping

2014-01-01

When a torque is applied to a shaft, normal strain oriented at ±45° direction to the shaft axis is at its maximum, which requires two one-port SAW resonators to be bonded to the shaft at ±45° to the shaft axis. In order to make the SAW torque sensitivity high enough, the installation angle error of two SAW resonators must be confined within ±5° according to our design requirement. However, there are few studies devoted to the installation angle analysis of a SAW torque sensor presently and the angle error was usually obtained by a manual method. Hence, we propose an approximation method to analyze the angle error. First, according to the sensitive mechanism of the SAW device to torque, the SAW torque sensitivity is deduced based on the linear piezoelectric constitutive equation and the perturbation theory. Then, when a torque is applied to the tested shaft, the stress condition of two SAW resonators mounted with an angle deviating from ±45° to the shaft axis, is analyzed. The angle error is obtained by means of the torque sensitivities of two orthogonal SAW resonators. Finally, the torque measurement system is constructed and the loading and unloading experiments are performed twice. The torque sensitivities of two SAW resonators are obtained by applying average and least square method to the experimental results. Based on the derived angle error estimation function, the angle error is estimated about 3.447°, which is close to the actual angle error 2.915°. The difference between the estimated angle and the actual angle is discussed. The validity of the proposed angle error analysis method is testified to by the experimental results. (technical design note)

AUTOMOTIVE DIESEL MAINTENANCE 2. UNIT V, AUTOMATIC TRANSMISSIONS--TORQUE CONVERTER.

Science.gov (United States)

Human Engineering Inst., Cleveland, OH.

THIS MODULE OF A 25-MODULE COURSE IS DESIGNED TO DEVELOP AN UNDERSTANDING OF THE OPERATION AND MAINTENANCE OF TORQUE CONVERTERS USED ON DIESEL POWERED VEHICLES. TOPICS ARE (1) FLUID COUPLINGS (LOCATION AND PURPOSE), (2) PRINCIPLES OF OPERATION, (3) TORQUE CONVERRS, (4) TORQMATIC CONVERTER, (5) THREE STAGE, THREE ELEMENT TORQUE CONVERTER, AND (6)…

A family of nonlinear PID-like regulators for a class of torque-driven robot manipulators equipped with torque-constrained actuators

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Adriana Salinas

2016-02-01

Full Text Available This article addresses the joint position control of torque-driven robot manipulators under actuators subject to torque saturation. Robots having viscous friction, but without gravity vector, are considered. By assuming a static model for the torque actuator (specifically, a model of nonlinear and non-differentiable hard saturation function, a family of nonlinear proportional–integral–derivative-like controllers is proposed. Lyapunov stability theory is used to establish conditions for local asymptotic stability of the closed-loop system. A notable feature of the proposed controller is that stability conditions do not depend on the saturation levels of the actuators. In addition, an experimental study complements the proposed theory.

Evaluation Method for Fieldlike-Torque Efficiency by Modulation of the Resonance Field

Science.gov (United States)

Kim, Changsoo; Kim, Dongseuk; Chun, Byong Sun; Moon, Kyoung-Woong; Hwang, Chanyong

2018-05-01

The spin Hall effect has attracted a lot of interest in spintronics because it offers the possibility of a faster switching route with an electric current than with a spin-transfer-torque device. Recently, fieldlike spin-orbit torque has been shown to play an important role in the magnetization switching mechanism. However, there is no simple method for observing the fieldlike spin-orbit torque efficiency. We suggest a method for measuring fieldlike spin-orbit torque using a linear change in the resonance field in spectra of direct-current (dc)-tuned spin-torque ferromagnetic resonance. The fieldlike spin-orbit torque efficiency can be obtained in both a macrospin simulation and in experiments by simply subtracting the Oersted field from the shifted amount of resonance field. This method analyzes the effect of fieldlike torque using dc in a normal metal; therefore, only the dc resistivity and the dimensions of each layer are considered in estimating the fieldlike spin-torque efficiency. The evaluation of fieldlike-torque efficiency of a newly emerging material by modulation of the resonance field provides a shortcut in the development of an alternative magnetization switching device.

Capacidade funcional de idosos atendidos em um programa do SUS em Belém (PA Functional capacity of the elderly attended in a Unified Health System (SUS program in Belém in the State of Pará

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Maria Izabel Penha de Oliveira Santos

2013-03-01

Full Text Available O objetivo deste estudo foi avaliar fatores associados à capacidade funcional em idosos atendidos em um programa de saúde pública em Belém (PA. Realizou-se estudo seccional com 259 idosos atendidos no programa Hiperdia/SUS no período de março a julho de 2010. Os idosos foram avaliados pelo teste de desempenho físico modificado, validado no Brasil. Nas análises foram utilizados o teste do qui-quadrado de Pearson, a análise de variância e a regressão. Os idosos tinham em média 68,3 anos (DP ± 6,2 e 71,0% eram do sexo feminino. Após ajustes por variáveis de confundimento, observaram-se maiores chances de pior desempenho no teste entre as mulheres, os mais velhos e os de menor escolaridade, além de queixa de dor no joelho, diagnóstico anterior de catarata e autoavaliação de saúde regular/ruim. A capacidade funcional é um indicador de saúde importante para se identificar precocemente riscos de incapacidade e requerendo uma avaliação periódica, no intuito de se buscar estratégias cuidativas para a manutenção da independência dos idosos.The objective of this study was to evaluate factors associated with functional capacity among the elderly attended in a public health program in Belém in the State of Pará. A sectional study was conducted with 259 elderly people attended in the Hiperdia/SUS program in the period from March to July 2010. The elderly were assessed using the modified physical performance test duly validated in Brazil. Pearson's Chi-square Test, in addition to variance analysis and logistic regression were used for the analysis. The elderly were 68.3 years on average (SD ± 6.2 and 71% were female. After adjustments for conflicting variables, it was seen that there were greater chances of worse performance on the test among women, the older and less educated individuals, and those complaining of knee pain and prior diagnosis of cataracts and fair/bad self-assessment of health. Functional capacity is an

Medidas directas e indirectas de las funciones ejecutivas en niños con trastorno de espectro autista

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María Fernanda Pérez Pichardo

2018-01-01

Full Text Available INTRODUCCIÓN: los niños con trastorno del espectro autista (TEA tienen dificultades en las funciones ejecutivas (FE pero se han sugerido discrepancias entre las medidas directas e indirectas.   OBJETIVO: conocer si existen diferencias en las funciones ejecutivas mediante medidas directas e indirectas entre niños con y sin TEA.   MÉTODO: se incluyeron 14 varones entre primero y tercero de primaria, 50% con diagnóstico de TEA y 50% con desarrollo neurotípico, seleccionados por emparejamiento en edad y grado escolar. El promedio de edad de la muestra fue de 7.43 (DE 0.98 años. Se aplicaron las pruebas de Evaluación neuropsicológica de funciones ejecutivas en niños (ENFEN y el Inventario de clasificación comportamental de las funciones ejecutivas (BRIEF.   RESULTADOS: se encontraron diferencias significativas en las medidas de las FE indirectas, pero no en las directas, entre los grupos (p < 0.05. Así mismo, las correlaciones entre las medidas directas e indirectas fueron mayores en el grupo con TEA.   CONCLUSIONES: los niños con TEA son evaluados con más dificultades en las medidas indirectas de las funciones ejecutivas, pero obtienen puntuaciones similares a los niños con desarrollo neurotípico cuando son evaluados en condiciones estructuradas empleando medidas directas.

Creative accomplishment of continuous TIP motor torque monitoring system in BWR plant

International Nuclear Information System (INIS)

Sun, C.H.; Li, I.N.; Liu, C.S.

1986-01-01

The Traveling In-core Probe (TIP) system is designed so delicate that the routine preventive maintenance - torque measurement is required to keep system operating properly. Normally, the torque measurement is performed by manually rotating torque wrench on the local TIP drive mechanism or using wattmeter during automatic operation. Whenever, either torque wrench or wattmeter measurement is performed, the high radiation exposure to maintenance personnel and mass manpower is expected. Because of this reason Taipower has developed a continuous TIP motor torque monitoring system to save manpower and minimize radiation exposure to maintenance personnel. This methods of TIP motor torque measurement will also predict TIP guide tube deterioration. (author)

Induction machine Direct Torque Control system based on fuzzy adaptive control

Science.gov (United States)

Li, Shi-ping; Yu, Yan; Jiao, Zhen-gang; Gu, Shu-sheng

2009-07-01

Direct Torque Control technology is a high-performance communication control method, it uses the space voltage vector method, and then to the inverter switch state control, to obtain high torque dynamic performance. But none of the switching states is able to generate the exact voltage vector to produce the desired changes in torque and flux in most of the switching instances. This causes a high ripple in torque. To solve this problem, a fuzzy implementation of Direct Torque Control of Induction machine is presented here. Error of stator flux, error of motor electromagnetic torque and position of angle of flux are taken as fuzzy variables. In order to further solve nonlinear problem of variation parameters in direct torque control system, the paper proposes a fuzzy parameter PID adaptive control method which is suitable for the direct torque control of an asynchronous motor. The generation of its fuzzy control is obtained by analyzing and optimizing PID control step response and combining expert's experience. For this reason, it carries out fuzzy work to PID regulator of motor speed to achieve to regulate PID parameters. Therefore the control system gets swifter response velocity, stronger robustness and higher precision of velocity control. The computer simulated results verify the validity of this novel method.

Performance of cycle diesel engine using Biodiesel of olive oil (B100 Desempenho de motor diesel quatro tempos alimentado com biodiesel de óleo de oliva (B100

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Carlos Eduardo Silva Volpato

2012-06-01

Full Text Available Biodiesel is a renewable fuel derived from vegetable oils used in diesel engines, in any proportion with petroleum diesel, or pure. It is produced by chemical processes, usually by transesterification, in which the glycerin is removed. The objective of this study was to compare the performance of a four stroke, four cylinder diesel cycle engines using either olive (B100 biodiesel oil or diesel oil. The following parameters were analyzed: effective and reduced power, torque, specific and hourly fuel consumption, thermo-mechanical and volumetric efficiency. Analysis of variance was performed on a completely randomized design with treatments in factorial and the Tukey test applied at the level of 5%. Five rotation speeds were researched in four replications (650, 570, 490, 410, 320 and 240 rpm. The engine fed with biodiesel presented more satisfactory results for torque, reduced power and specific and hourly consumptions than that fed with fossil diesel.Biodiesel é um combustível renovável derivado de óleos vegetais, usado em motores de ciclo diesel, em qualquer proporção com o diesel mineral, ou puro. É produzido por meio de processos químicos, normalmente por transesterificação, no qual é removida a glicerina. Este trabalho foi realizado com o objetivo de avaliar o desempenho de um motor de ciclo diesel quatro tempos e quatro cilindros, utilizando biodiesel de óleo de oliva (B100, em comparação ao óleo diesel. Foram analisados os parâmetros: potência efetiva e reduzida, torque, consumo específico e energético de combustível, eficiência termomecânica e volumétrica. Foi instalado um ensaio com delineamento inteiramente casualizado (DIC em esquema fatorial, realizada análise de variância e aplicado teste de Tukey, a 5%. Foram pesquisados cinco níveis de rotação em quatro repetições (650, 570, 490, 410, 320 e 240 rpm. O motor alimentado com biodiesel de oliva apresentou torque, potencia reduzida e consumos especifico e

Validity of trunk extensor and flexor torque measurements using isokinetic dynamometry.

Science.gov (United States)

Guilhem, Gaël; Giroux, Caroline; Couturier, Antoine; Maffiuletti, Nicola A

2014-12-01

This study aimed to evaluate the validity and test-retest reliability of trunk muscle strength testing performed with a latest-generation isokinetic dynamometer. Eccentric, isometric, and concentric peak torque of the trunk flexor and extensor muscles was measured in 15 healthy subjects. Muscle cross sectional area (CSA) and surface electromyographic (EMG) activity were respectively correlated to peak torque and submaximal isometric torque for erector spinae and rectus abdominis muscles. Reliability of peak torque measurements was determined during test and retest sessions. Significant correlations were consistently observed between muscle CSA and peak torque for all contraction types (r=0.74-0.85; Ptorque (r ⩾ 0.99; Ptorque between test and retest ranged from -3.7% to 3.7% with no significant mean directional bias. Overall, our findings establish the validity of torque measurements using the tested trunk module. Also considering the excellent test-retest reliability of peak torque measurements, we conclude that this latest-generation isokinetic dynamometer could be used with confidence to evaluate trunk muscle function for clinical or athletic purposes. Copyright © 2014 Elsevier Ltd. All rights reserved.

Spin Transfer Torque in Graphene

Science.gov (United States)

Lin, Chia-Ching; Chen, Zhihong

2014-03-01

Graphene is an idea channel material for spin transport due to its long spin diffusion length. To develop graphene based spin logic, it is important to demonstrate spin transfer torque in graphene. Here, we report the experimental measurement of spin transfer torque in graphene nonlocal spin valve devices. Assisted by a small external in-plane magnetic field, the magnetization reversal of the receiving magnet is induced by pure spin diffusion currents from the injector magnet. The magnetization switching is reversible between parallel and antiparallel configurations by controlling the polarity of the applied charged currents. Current induced heating and Oersted field from the nonlocal charge flow have also been excluded in this study. Next, we further enhance the spin angular momentum absorption at the interface of the receiving magnet and graphene channel by removing the tunneling barrier in the receiving magnet. The device with a tunneling barrier only at the injector magnet shows a comparable nonlocal spin valve signal but lower electrical noise. Moreover, in the same preset condition, the critical charge current density for spin torque in the single tunneling barrier device shows a substantial reduction if compared to the double tunneling barrier device.

Envelhecimento ativo e sua relação com a independência funcional

OpenAIRE

Ferreira, Olívia Galvão Lucena; Maciel, Silvana Carneiro; Costa, Sônia Maria Gusmão; Silva, Antonia Oliveira; Moreira, Maria Adelaide Silva Paredes

2012-01-01

O objetivo da presente pesquisa foi analisar os fatores determinantes de um envelhecimento ativo e sua relação com a independência funcional. A pesquisa foi realizada com 100 idosos de uma Unidade de Saúde da Família, em João Pessoa-PB. Como instrumentos para a avaliação dos idosos foram utilizados a Medida de Independência Funcional e um questionário sociodemográfico. Os dados foram analisados através do software SPSS. De acordo com os resultados, todos os idosos apresentaram independência f...

Comparison of design and torque measurements of various manual wrenches.

Science.gov (United States)

Neugebauer, Jörg; Petermöller, Simone; Scheer, Martin; Happe, Arndt; Faber, Franz-Josef; Zoeller, Joachim E

2015-01-01

Accurate torque application and determination of the applied torque during surgical and prosthetic treatment is important to reduce complications. A study was performed to determine and compare the accuracy of manual wrenches, which are available in different designs with a large range of preset torques. Thirteen different wrench systems with a variety of preset torques ranging from 10 to 75 Ncm were evaluated. Three different designs were available, with a spring-in-coil or toggle design as an active mechanism or a beam as a passive mechanism, to select the preset torque. To provide a clinically relevant analysis, a total of 1,170 torque measurements in the range of 10 to 45 Ncm were made in vitro using an electronic torque measurement device. The absolute deviations in Ncm and percent deviations across all wrenches were small, with a mean of -0.24 ± 2.15 Ncm and -0.84% ± 11.72% as a shortfall relative to the preset value. The greatest overage was 8.2 Ncm (82.5%), and the greatest shortfall was 8.47 Ncm (46%). However, extreme values were rare, with 95th-percentile values of -1.5% (lower value) and -0.16% (upper value). A comparison with respect to wrench design revealed significantly higher deviations for coil and toggle-style wrenches than for beam wrenches. Beam wrenches were associated with a lower risk of rare extreme values thanks to their passive mechanism of achieving the selected preset torque, which minimizes the risk of harming screw connections.

Deliberate utilization of interaction torques brakes elbow extension in a fast throwing motion.

Science.gov (United States)

Hore, Jon; Debicki, Derek B; Gribble, Paul L; Watts, Sherry

2011-05-01

We tested the hypothesis that in fast arm movements the CNS deliberately utilizes interaction torques to decelerate (brake) joint rotations. Twelve subjects performed fast 2-D overarm throws in which large elbow extension velocities occurred. Joint motions were computed from recordings made with search coils; joint torques were calculated using inverse dynamics. After ball release, a large follow-through shoulder extension acceleration occurred that was initiated by shoulder extensor muscle torque. This shoulder acceleration produced a flexor interaction torque at the elbow that initiated elbow deceleration (braking). An instantaneous mechanical interaction of passive torques then occurred between elbow and shoulder, i.e., elbow extension deceleration produced a large shoulder extensor interaction torque that contributed to the shoulder extension acceleration which, simultaneously, produced a large elbow flexor interaction torque that contributed to elbow extension deceleration, and so on. Late elbow flexor muscle torque also contributed to elbow deceleration. The interaction of passive torques between shoulder and elbow was braked by shoulder flexor muscle torque. In this mechanism, shoulder musculature contributed to braking elbow extension in two ways: shoulder extensors initiated the mechanical interaction of passive torques between shoulder and elbow and shoulder flexors dissipated kinetic energy from elbow braking. It is concluded that, in fast 2-D throws, the CNS deliberately utilizes powerful interaction torques between shoulder and elbow to brake motion at the elbow.

Rastreio de tuberculose nos funcionários de um Hospital Distrital

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Jorge Pedrosa

1998-03-01

Full Text Available RESUMO: INTRODUÇÃO – após terem surgido dois casos com baciloscopias positivas em funcionários do Hospital Distrital de Oliveira de Azeméis em 1996, foi feito um rastreio de tuberculose em todos os profissionais desse Hospital.MATERIAL E MÉTODOS – foi afixado um aviso em todos os Serviços solicitando aos funcionários a realização da prova de tuberculina. Esta foi efectuada mediante injecçãao intra-dérmica de 2 unidades PPD (RT 23, por um único profissional de enfermagem. Aderiram à prova de Mantoux 202 dos 241 funcionários.Em todos os funcionários que referiram sintomas respiratórios (tosse e expectoração, foi efectuada telerradiografia de torax e baciloscopias em amostras após coloração pelo metodo de Ziebl-Neelsen e exame cultural em meio de Lowenstein-Jensen (exames realizados em 27 funcionários.RESULTADOS – foram encontrados 11 easos de tuberculose-infecção em indivíduos com menos de 35 anos (tendo 9 feito tratamento com terapêutica trip la durante dois meses e 6 casos de tuberculose pulmonar com baciloscopias positivas e confirmados no exame cultural.CONCLUSÕES – do estudo realízado concluiu-se que a incidência de tuberculose pulmonar nos funcionários do Hospital Distrital de Oliveira de Azeméis em 1996 foi de 2,54%, o que corresponde aproximadamente ao triplo da incidência na população em geral da área em questão.REV PORT PNEUMOL 1998; IV (2: 147- 153 ABSTRACT: BACKGROUND: After two cases of Pulmonary Tuberculosis were found in healthcare workers of a Regional Hospital in Portugal a study was done to determine the incidence of Tuberculosis in health-workers of the Oliveira de Azeméis Hospital in 1996.METHODS: An information-note was affixed in all Services asking all the workers to do the Tuberculin-test. An intradermic injection of 2 U. of PPD (RT 23, by one trained nurse was done in 202 of 241 health

Spin-transfer torque generated by a topological insulator

KAUST Repository

Mellnik, A. R.; Lee, Joonsue; Richardella, Anthony R.; Grab, J. L.; Mintun, P. J.; Fischer, Mark H.; Vaezi, Abolhassan; Manchon, Aurelien; Kim, Eunah; Samarth, Nitin S.; Ralph, Daniel C.

2014-01-01

permalloy (Ni81Fe19) thin film, with a direction consistent with that expected from the topological surface state. We find that the strength of the torque per unit charge current density in Bi 2Se3 is greater than for any source of spin-transfer torque

A influência do gênero e idade no desempenho das habilidades locomotoras de crianças de primeira infância

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Dayana da Silva Oliveira

2013-12-01

Full Text Available Na primeira infância é esperada uma melhora no desempenho de habilidades locomotoras com o avanço da idade. Pode também haver diferenças entre meninos e meninas devido à especificidade da tarefa motora. Este estudo teve como objetivo analisar o desempenho de crianças em habilidades locomotoras de acordo com idade e gênero. O desempenho locomotor de 389 pré-escolares de três a cinco anos da cidade do Recife - PE foi avaliado mediante o TGMD-2. Os resultados mostraram que: crianças mais velhas apresentaram melhor desempenho motor; no geral, meninos obtiveram melhor desempenho no correr, salto horizontal, deslize lateral e escore total locomotor, e meninas no saltitar com um pé aos cinco anos de idade; na análise da progressão do desenvolvimento motor, comportamentos motores mais complexos ocorreram após aqueles considerados menos complexos. Conclui-se que o desenvolvimento locomotor dos pré-escolares recifenses obedeceu aos princípios da progressividade e do aumento da complexidade, entretanto, meninos e meninas mostraram diferenças no seu desempenho dependendo da tarefa.

Indicadores de desempenho em um laboratório de diagnóstico animal = Performance indicators in an animal diagnostic laboratory

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Sílvio Orlan de Castro Chaves

2018-06-01

Full Text Available A utilização dos indicadores da qualidade vem sendo estimulada nos laboratórios para melhorar a qualificaçã o e a quantificaçã o dos erros nos diferentes processos laboratoriais, bem como para ajudar na implantaçã o de medidas corretivas e preventivas e indicar a eficá cia das açõ es realizadas. Este trabalho tem como objetivo avaliar indicadores de desempenho durante o ano de 2015 e de 2016 em um laboratório de diagnóstico animal localizado em Belém, estado do Pará. Dessa forma, utilizou-se quatro indicadores de desempenho do laboratório: nú mero de açõ es de divulgaçã o do laboratório para sociedade; desempenho temporal; percentual de ensaios acreditados e percentual de execução do plano de capacitação. Todos os ensaios ofertados pelo laboratório são acreditados na ABNT NBR ISO/IEC 17025:2005. Verificou-se que não houve ações de divulgação do laboratório no ano de 2015, entretanto, no ano de 2016, ocorreram sete ações de divulgação do laboratório em diferentes estados do Brasil. As amostras com relatórios de ensaio fornecidos dentro do prazo estipulado para os clientes decresceram 1,5% entre o ano de 2015 (92,7% para 2016 (91,2%. O percentual de capacitação dos funcionários foi nulo no ano de 2015 (0% e pouco expressivo em 2016 (16,7%. Conclui-se que o laboratório em estudo apresenta bons indicadores de desempenho temporal e de acreditação, porém deve atentar para melhoria continua das ações futuras de divulgação da instituição e para o treinamento de pessoal a fim de atender plenamente o planejamento estratégico do órgão. = The use of quality indicators has been valued in the management of laboratories to optimize the qualification and quantification of failures in different laboratory processes, as well as to assist in the implementation of corrective and preventive measures and to indicate the effectiveness of the actions taken. This study aims to evaluate key

Medição de desempenho numa confecção de vestuário: integrando ergonomia situada ao processo de implementação e uso de indicadores de desempenho

OpenAIRE

Carlos Antonio Pizo

2011-01-01

Esta pesquisa busca descrever, na dinâmica organizacional de uma média empresa de confecção do vestuário, mais especificamente em sua unidade de costura, as mudanças ocorridas durante a implementação e uso de indicadores de desempenho quando agregado em seu desenvolvimento os conceitos e método da ergonomia situada. Os Sistemas de Medição de Desempenho (SMDs) sempre estiveram presentes nas organizações e vem nas últimas décadas tornando-se mais importantes devido à competitividade e às mudanç...

Torque magnetometry by use of capacitance type transducer

International Nuclear Information System (INIS)

Braught, M.C.; Pechan, M.J.

1992-01-01

Interfacial anisotropy in magnetic multilayered samples comprised of nanometer thick magnetic layers alternating with non-magnetic layers is investigated by torque magnetometry in the temperature regime of 4 to 300K. The design, construction and use of a capacitance type transducer wherein the sample is mounted directly on with the plate of the capacitor, will be described. As a result the sample and transducer spatially coexist at the sample temperature in an applied external field, eliminating mechanical coupling from the cryogenic region to a remote room temperature transducer. The capacitor measuring the torque of the sample is paired with a reference capacitor. The difference between torque influenced capacitance and the reference is then determined by a differential transimpedance amplifier. Since both capacitors are physically identical variables such as temperature, vibration, orientation and external devices are minimized. Torques up to 300 dyne-cm can be measured with a sensitivity of 0.010 dyne-cm

Interdependencia Funcional de la Crianza Positiva Materna

OpenAIRE

Gaxiola Romero, José Concepción; Universidad de Sonora; Gaxiola Villa, Eunice; Frías Armenta, Martha

2017-01-01

Según la teoría del desarrollo de la psicopatología, algunas trayectorias del desarrollo resultan en adaptación, otras en psicopatología. Nuestra hipótesis es que algunas variables positivas son funcionales a la adaptación psicológica y participan en nicho adaptativos, que son contextos donde regularmente encontramos las competencias adaptativas, como el estilo de crianza positivo materno. El objetivo del estudio fue probar en un modelo de trayectorias, la interdependencia funcional del estil...

Relações entre desempenho escolar e orientações motivacionais Relations between school performance and motivational orientations

Directory of Open Access Journals (Sweden)

Selma de Cássia Martinelli

2009-04-01

Full Text Available O objetivo deste estudo foi investigar as relações entre desempenho escolar de alunos do ensino fundamental e suas orientações motivacionais. Participaram 150 estudantes, entre 9 e 12 anos de idade, de uma escola pública do Estado de São Paulo, que cursavam a 3ª e 4ª séries do ensino fundamental. Os resultados revelaram que na terceira série houve uma correlação significativa e negativa entre motivação extrínseca e desempenho escolar, ou seja, quanto menor o desempenho escolar maior a motivação extrínseca. No que diz respeito à motivação intrínseca e o desempenho escolar, as variáveis não apresentaram correlação significativa. Na 4ª série houve uma correlação significativa e negativa entre motivação extrínseca e desempenho escolar, ou seja, quanto menor o desempenho escolar maior a motivação extrínseca. No que diz respeito à motivação intrínseca e o desempenho escolar as variáveis apresentaram correlação significativa e positiva, indicando que quanto maior o desempenho maior a motivação intrínseca.The intent of this research was to investigate if a relationship exists between the school performance and the motivational orientations from elementary students. Participants were 150 male and female elementary school children, aged between 9 and 12 years of two public schools from Sao Paulo State. The results indicated that in the third-grade there was a negative and significant correlation between extrinsic motivation and the school performance, that is, the lower the school performance the higher the extrinsic motivation. For the intrinsic motivation and school performance, variables showed no significant correlation and extrinsic motivation and in the fourth-grade, the results showed a significant and positive correlation. For the fourth-grade, there was a negative and significant correlation between extrinsic motivation and school performance, that is, the lower the school performance the higher the

Comparação entre desempenhos de corrida time trial realizados em pista e esteira

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Cecília Segabinazi Peserico

2014-05-01

Poucos estudos verificaram a influência do ambiente de teste (campo e laboratório sobre o ritmo de corrida e variáveis fisiológicas obtidas durante o desempenho em corrida de endurance. Portanto, o objetivo deste estudo foi comparar o comportamento da velocidade média (VM, ritmo de corrida, frequência cardíaca (FC e percepção subjetiva de esforço (PSE obtidas durante os desempenhos de corrida em provas time trial de uma hora realizados em pista de atletismo e em esteira. Dezoito homens corredores recreacionais (25,4 ± 3,3 anos realizaram duas performances de uma hora de corrida: uma em esteira e outra em pista de atletismo de 400 m. A PSE e a FC foram registradas a cada 10 minutos, e a VM a cada 15 minutos para a determinação do ritmo de corrida. As variáveis relacionadas aos desempenhos foram comparadas pelo teste t de Student para amostras pareadas. Os valores de VM, FC e PSE obtidos durante diferentes momentos das provas foram comparados pela Anova de dois fatores para medidas repetidas seguido do post hoc de Bonferroni. Para todas as análises, foi adotado nível de significância de P< 0,05. A VM da prova realizada em pista (12,2 ± 0,8 km·h-1 foi superior à prova em esteira (11,8 ± 0,8 km·h-1. Além disso, foram encontradas diferenças entre os dois desempenhos para os valores de frequência cardíaca média e máxima, e para o ritmo de corrida. A partir dessas diferenças, conclui-se que os desempenhos foram influenciados pelo ambiente onde as provas de uma hora foram realizadas.

Disfagia orofaríngea em pacientes com esclerose múltipla: as escalas de classificação da doença refletem a gravidade da disfagia?

Directory of Open Access Journals (Sweden)

Alessandro Murano Ferré Fernandes

2013-08-01

Full Text Available A esclerose múltipla é uma afecção neurológica que envolve distúrbios da deglutição. Muitos estudos têm mostrado associação entre o comprometimento neurológico e o desempenho da deglutição, porém, os resultados têm sido conflitantes. OBJETIVO: Identificar a frequência de disfagia nos pacientes com esclerose múltipla e os indicadores neurológicos que podem representar o desempenho da deglutição. MÉTODO: Neste estudo (estudo transversal, 120 pacientes com esclerose múltipla foram submetidos à avaliação funcional da deglutição por fibronasofaringolaringoscopia, cujos resultados foram comparados com a pontuação das escalas de classificação (Formas Clínicas Evolutivas da Doença, Escala de Incapacidade Funcional por Sistemas e Escala Ampliada de Incapacidade Funcional [Kurtzke Expanded Disability Status Scale]. RESULTADOS: A disfagia foi identificada em 90% dos pacientes. Dentre as formas clínicas, as formas progressivas (primária progressiva e secundária progressiva apresentaram com maior frequência disfagia grave, enquanto a forma remitente-recorrente apresentou mais frequentemente disfagia leve e moderada. Em relação à Escala de Incapacidade Funcional por Sistemas, as funções cerebelares, do tronco encefálico e mental tiveram associação com a disfagia, especialmente na forma grave. Quanto à Escala Ampliada de Incapacidade Funcional, pontuações mais altas se associaram aos quadros graves de disfagia. CONCLUSÃO: A disfagia é frequente em pacientes com esclerose múltipla, especialmente naqueles com maior comprometimento das funções neurológicas.

Torque Generation of Enterococcus hirae V-ATPase*

Science.gov (United States)

Ueno, Hiroshi; Minagawa, Yoshihiro; Hara, Mayu; Rahman, Suhaila; Yamato, Ichiro; Muneyuki, Eiro; Noji, Hiroyuki; Murata, Takeshi; Iino, Ryota

2014-01-01

V-ATPase (VoV1) converts the chemical free energy of ATP into an ion-motive force across the cell membrane via mechanical rotation. This energy conversion requires proper interactions between the rotor and stator in VoV1 for tight coupling among chemical reaction, torque generation, and ion transport. We developed an Escherichia coli expression system for Enterococcus hirae VoV1 (EhVoV1) and established a single-molecule rotation assay to measure the torque generated. Recombinant and native EhVoV1 exhibited almost identical dependence of ATP hydrolysis activity on sodium ion and ATP concentrations, indicating their functional equivalence. In a single-molecule rotation assay with a low load probe at high ATP concentration, EhVoV1 only showed the “clear” state without apparent backward steps, whereas EhV1 showed two states, “clear” and “unclear.” Furthermore, EhVoV1 showed slower rotation than EhV1 without the three distinct pauses separated by 120° that were observed in EhV1. When using a large probe, EhVoV1 showed faster rotation than EhV1, and the torque of EhVoV1 estimated from the continuous rotation was nearly double that of EhV1. On the other hand, stepping torque of EhV1 in the clear state was comparable with that of EhVoV1. These results indicate that rotor-stator interactions of the Vo moiety and/or sodium ion transport limit the rotation driven by the V1 moiety, and the rotor-stator interactions in EhVoV1 are stabilized by two peripheral stalks to generate a larger torque than that of isolated EhV1. However, the torque value was substantially lower than that of other rotary ATPases, implying the low energy conversion efficiency of EhVoV1. PMID:25258315

[Influence of slot size on torque control].

Science.gov (United States)

Tian, Jun; Liu, Zhong-Hao; Zhang, Ding; Wu, Chuan-Jun

2009-12-01

To study the influence of two slot size brackets on torque control when teeth interacted in the same arch. After the upper arch was aligned and leveled in Typodont study, the inclinations of upper teeth 5 +/- 5 were measured when 0.457 2 mm x 0.635 0 mm OPA-K brackets and 0.558 8 mmx0.711 2 mm OPA-K brackets were filled with 0.431 8 mm x 0.635 0 mm stainless steel wire. This experiment was duplicated 10 times. The inclin of each tooth were transformed to the absolute values of the torque play angle psi by computing program, and paired-t test was used. The two kinds of slot size brackets were different with statistical significance on torque control. When the brackets were filled with 0.431 8 mm x 0.635 0 mm stainless steel wire, the absolute values of the angle psi in 0.558 8 mm x 0.711 2 mm and 0.457 2 mm x 0.635 0 mm slot size brackets were 6.140 degrees +/- 3.758 degrees and 2.608 degrees +/- 1.479 degrees respectively, and the average difference of that between the two slot size brackets was 3.532 degrees. The absolute values of the angle psi in the upper left and right canine brackets were 2.560 degrees +/- 2.605 degrees, 4.230 degrees +/- 2.817 degrees, 1.260 degrees +/- 0.747 degrees and 2.070 degrees +/- 0.663 degrees respectively, and average differences between them were smaller than that in the other teeth. There was difference between the two kinds of slot size brackets on torque control, and 0.457 2 mm x 0.635 0 mm slot size bracket controls torque better when filled with the same size wire. In this study, the teeth interaction in the same arch probably caused the result that the difference of two slot size brackets on torque control was less than the study results of the theory calculations and material studys before.

Condition monitoring of a motor-operated valve using estimated motor torque

International Nuclear Information System (INIS)

Chai, Jangbom; Kang, Shinchul; Park, Sungkeun; Hong, Sungyull; Lim, Chanwoo

2004-01-01

This paper is concerned with the development of data analysis methods to be used in on-line monitoring and diagnosis of Motor-Operated Valves (MOVs) effectively and accurately. The technique to be utilized includes the electrical measurements and signal processing to estimate electric torque of induction motors, which are attached to most of MOV systems. The estimated torque of an induction motor is compared with the directly measured torque using a torque cell in various loading conditions including the degraded voltage conditions to validate the estimating scheme. The accuracy of the estimating scheme is presented. The advantages of the estimated torque signatures are reviewed over the currently used ones such as the current signature and the power signature in several respects: accuracy, sensitivity, resolution and so on. Additionally, the estimated torque methods are suggested as a good way to monitor the conditions of MOVs with higher accuracy. (author)

Study on Monitoring Rock Burst through Drill Pipe Torque

OpenAIRE

Zhonghua Li; Liyuan Zhu; Wanlei Yin; Yanfang Song

2015-01-01

This paper presents a new method to identify the danger of rock burst from the response of drill pipe torque during drilling process to overcome many defects of the conventional volume of drilled coal rubble method. It is based on the relationship of rock burst with coal stress and coal strength. Through theoretic analysis, the change mechanism of drill pipe torque and the relationship of drill pipe torque with coal stress, coal strength, and drilling speed are investigated. In light of the a...

Development of a New Small-Rated Reference Torque Wrench

Science.gov (United States)

Nishino, Atsuhiro; Ogushi, Koji; Ueda, Kazunaga

It is imperative that torque standard of small rated capacity is established and disseminated throughout Japanese industry. A 10 N·m dead weight torque standard machine (10-N·m-DWTSM) has been developed and evaluated at the National Metrology Institute of Japan (NMIJ), part of the National Institute of Advanced Industrial Science and Technology (AIST). By 2012, the relative expanded uncertainty of torque realized by the 10-N·m-DWTSM was estimated to be 6.6 × 10-5, with the coverage factor k begin equal to 2, in a range from 0.1 N·m to 10 N·m for calibrations of the torque measuring devices (TMDs). Calibration service for small-rated-capacity TMDs was started to disseminate the torque standard throughout Japanese industry. Here, there are two routes in the torque traceability system in Japan. One is the route for TMDs and the other one is the route for reference torque wrenches (RTWs). The torque standard in the form of RTWs has been disseminated in the range from 5 N·m to 5 kN·m by using the TSMs owned by NMIJ. There remains a strong demand to expand the calibration range of RTWs. To expand the range, we should develop the new high-accuracy small-rated-capacity RTW and evaluate its calibration method. In this study, a high-accuracy RTW (TP-5N-1109), which had a rated capacity of 5 N·m, was newly developed and calibrated with the 10-N·m-DWTSM to evaluate its characteristics. The ordinary calibration procedures adopted at NMIJ was investigated whether it was applicable to the small-rated-capacity RTWs. As a result, the TP-5N-1109 showed good performance in the creep testing, and its characteristic curves were draw for all cases of the calibration procedures. The repeatability in the calibration results was good. We clarified the problem with the calibration conditions of the small-rated-capacity RTW to calibrate it by three cases.

Pelvic rotation torque during fast-pitch softball hitting under three ball height conditions.

Science.gov (United States)

Iino, Yoichi; Fukushima, Atsushi; Kojima, Takeji

2014-08-01

The purpose of this study was to investigate the relevance of hip joint angles to the production of the pelvic rotation torque in fast-pitch softball hitting and to examine the effect of ball height on this production. Thirteen advanced female softball players hit stationary balls at three different heights: high, middle, and low. The pelvic rotation torque, defined as the torque acting on the pelvis through the hip joints about the pelvic superior-inferior axis, was determined from the kinematic and force plate data using inverse dynamics. Irrespective of the ball heights, the rear hip extension, rear hip external rotation, front hip adduction, and front hip flexion torques contributed to the production of pelvic rotation torque. Although the contributions of the adduction and external rotation torques at each hip joint were significantly different among the ball heights, the contributions of the front and rear hip joint torques were similar among the three ball heights owing to cancelation of the two torque components. The timings of the peaks of the hip joint torque components were significantly different, suggesting that softball hitters may need to adjust the timings of the torque exertions fairly precisely to rotate the upper body effectively.

MUSCLE WEAKNESS, FATIGUE, AND TORQUE VARIABILITY: EFFECTS OF AGE AND MOBILITY STATUS

Science.gov (United States)

KENT-BRAUN, JANE A.; CALLAHAN, DAMIEN M.; FAY, JESSICA L.; FOULIS, STEPHEN A.; BUONACCORSI, JOHN P.

2013-01-01

Introduction Whereas deficits in muscle function, particularly power production, develop in old age and are risk factors for mobility impairment, a complete understanding of muscle fatigue during dynamic contractions is lacking. We tested hypotheses related to torque-producing capacity, fatigue resistance, and variability of torque production during repeated maximal contractions in healthy older, mobility-impaired older, and young women. Methods Knee extensor fatigue (decline in torque) was measured during 4 min of dynamic contractions. Torque variability was characterized using a novel 4-component logistic regression model. Results Young women produced more torque at baseline and during the protocol than older women (P torque variability differed by group (P = 0.022) and was greater in older impaired compared with young women (P = 0.010). Conclusions These results suggest that increased torque variability may combine with baseline muscle weakness to limit function, particularly in older adults with mobility impairments. PMID:23674266

Fatigue affects peak joint torque angle in hamstrings but not in quadriceps.

Science.gov (United States)

Coratella, Giuseppe; Bellin, Giuseppe; Beato, Marco; Schena, Federico

2015-01-01

Primary aim of this study was to investigate peak joint torque angle (i.e. the angle of peak torque) changes recorded during an isokinetic test before and after a fatiguing soccer match simulation. Secondarily we want to investigate functional Hecc:Qconc and conventional Hconc:Qconc ratio changes due to fatigue. Before and after a standardised soccer match simulation, twenty-two healthy male amateur soccer players performed maximal isokinetic strength tests both for hamstrings and for quadriceps muscles at 1.05 rad · s(‒1), 3.14 rad · s(‒1) and 5.24 rad · s(‒1). Peak joint torque angle, peak torque and both functional Hecc:Qconc and conventional Hconc:Qconc ratios were examined. Both dominant and non-dominant limbs were tested. Peak joint torque angle significantly increased only in knee flexors. Both eccentric and concentric contractions resulted in such increment, which occurred in both limbs. No changes were found in quadriceps peak joint torque angle. Participants experienced a significant decrease in torque both in hamstrings and in quadriceps. Functional Hecc:Qconc ratio was lower only in dominant limb at higher velocities, while Hconc:Qconc did not change. This study showed after specific fatiguing task changes in hamstrings only torque/angle relationship. Hamstrings injury risk could depend on altered torque when knee is close to extension, coupled with a greater peak torque decrement compared to quadriceps. These results suggest the use eccentric based training to prevent hamstrings shift towards shorter length.

Experimental and theoretical study of friction torque from radial ball bearings

Science.gov (United States)

Geonea, Ionut; Dumitru, Nicolae; Dumitru, Ilie

2017-10-01

In this paper it is presented a numerical simulation and an experimental study of total friction torque from radial ball bearings. For this purpose it is conceived a virtual CAD model of the experimental test bench for bearing friction torque measurement. The virtual model it is used for numerical simulation in Adams software, that allows dynamic study of multi-body systems and in particularly with facility Adams Machinery of dynamic behavior of machine parts. It is manufactured an experimental prototype of the test bench for radial ball bearings friction torque measurement. In order to measure the friction torque of the tested bearings it is used an equal resistance elastic beam element, with strain gauge transducer to measure bending deformations. The actuation electric motor of the bench has the shaft mounted on two bearings and the motor housing is fixed to the free side of the elastic beam, which is bended by a force proportional with the total friction torque. The beam elastic element with strain gauge transducer is calibrated in order to measure the force occurred. Experimental determination of the friction torque is made for several progressive radial loads. It is established the correlation from the friction torque and bearing radial load. The bench allows testing of several types and dimensions of radial bearings, in order to establish the bearing durability and of total friction torque.

New Cogging Torque Reduction Methods for Permanent Magnet Machine

Science.gov (United States)

Bahrim, F. S.; Sulaiman, E.; Kumar, R.; Jusoh, L. I.

2017-08-01

Permanent magnet type motors (PMs) especially permanent magnet synchronous motor (PMSM) are expanding its limbs in industrial application system and widely used in various applications. The key features of this machine include high power and torque density, extending speed range, high efficiency, better dynamic performance and good flux-weakening capability. Nevertheless, high in cogging torque, which may cause noise and vibration, is one of the threat of the machine performance. Therefore, with the aid of 3-D finite element analysis (FEA) and simulation using JMAG Designer, this paper proposed new method for cogging torque reduction. Based on the simulation, methods of combining the skewing with radial pole pairing method and skewing with axial pole pairing method reduces the cogging torque effect up to 71.86% and 65.69% simultaneously.

MEDIDAS DE DESEMPENHO E ONTOLOGIAS: UM ESTUDO BIBLIOMÉTRICO PARA IDENTIFICAÇÃO DO USO DE ONTOLOGIAS PARA O SUPORTE DOS PROCESSOS DE MEDIDAS DE DESEMPENHO

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Vanderlei Freitas Junior

2015-09-01

Full Text Available O presente trabalho se propõe analisar as publicações internacionais acerca do emprego das ontologias no contexto de medidas de desempenho. Para isso, foi realizada uma pesquisa bibliométrica em três bases de dados internacionais: Web of Science, Scopus e IEEE. Essa pesquisa foi desenvolvida em duas grandes etapas: (i busca sistemática da literatura, e (ii análise e síntese das informações bibliométricas. Foram localizados 115 trabalhos, escritos por 362 autores vinculados a 84 instituições de 101 países diferentes e estão publicados em 38 periódicos. Os autores identificaram ainda 981 palavras-chave diferentes em seus estudos. Os estudos, de maneira geral, evidenciam a possibilidade de utilização das ontologias como ferramenta semântica em diversas etapas e momentos do processo de medidas de desempenho, especialmente no que tange à representação do conhecimento e elu-cidação dos indicadores chaves, permitindo a interoperabilidade destes indicadores. A partir da identificação destes estudos o presente trabalho contribui para a compreensão das possibilidades de aplicação das ontologias para o suporte aos pro-cessos de medida de desempenho, realizando o mapeamento das publicações inter-nacionais desta temática e evidenciando a possibilidade de representação do conhecimento envolvido nesta tarefa.

Self-consistent perturbed equilibrium with neoclassical toroidal torque in tokamaks

International Nuclear Information System (INIS)

Park, Jong-Kyu; Logan, Nikolas C.

2017-01-01

Toroidal torque is one of the most important consequences of non-axisymmetric fields in tokamaks. The well-known neoclassical toroidal viscosity (NTV) is due to the second-order toroidal force from anisotropic pressure tensor in the presence of these asymmetries. This work shows that the first-order toroidal force originating from the same anisotropic pressure tensor, despite having no flux surface average, can significantly modify the local perturbed force balance and thus must be included in perturbed equilibrium self-consistent with NTV. The force operator with an anisotropic pressure tensor is not self-adjoint when the NTV torque is finite and thus is solved directly for each component. This approach yields a modified, non-self-adjoint Euler-Lagrange equation that can be solved using a variety of common drift-kinetic models in generalized tokamak geometry. The resulting energy and torque integral provides a unique way to construct a torque response matrix, which contains all the information of self-consistent NTV torque profiles obtainable by applying non-axisymmetric fields to the plasma. This torque response matrix can then be used to systematically optimize non-axisymmetric field distributions for desired NTV profiles. Published by AIP Publishing.

A theoretical model of speed-dependent steering torque for rolling tyres

Science.gov (United States)

Wei, Yintao; Oertel, Christian; Liu, Yahui; Li, Xuebing

2016-04-01

It is well known that the tyre steering torque is highly dependent on the tyre rolling speed. In limited cases, i.e. parking manoeuvre, the steering torque approaches the maximum. With the increasing tyre speed, the steering torque decreased rapidly. Accurate modelling of the speed-dependent behaviour for the tyre steering torque is a key factor to calibrate the electric power steering (EPS) system and tune the handling performance of vehicles. However, no satisfactory theoretical model can be found in the existing literature to explain this phenomenon. This paper proposes a new theoretical framework to model this important tyre behaviour, which includes three key factors: (1) tyre three-dimensional transient rolling kinematics with turn-slip; (2) dynamical force and moment generation; and (3) the mixed Lagrange-Euler method for contact deformation solving. A nonlinear finite-element code has been developed to implement the proposed approach. It can be found that the main mechanism for the speed-dependent steering torque is due to turn-slip-related kinematics. This paper provides a theory to explain the complex mechanism of the tyre steering torque generation, which helps to understand the speed-dependent tyre steering torque, tyre road feeling and EPS calibration.

Avaliação de requisitos de desempenho de Sistemas de Proteção Periférica (SPP

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Guillermina Andrea Peñaloza

Full Text Available ResumoEmbora o uso de sistemas de proteções periféricas (SPP seja importante para prevenir quedas de altura na construção civil, a literatura não apresenta de forma abrangente os requisitos de desempenho para a avaliação do desempenho dos mesmos. O objetivo deste estudo consiste em propor um conjunto de requisitos para avaliar o desempenho para estes sistemas. Foi desenvolvido um protocolo que contém critérios qualitativos e quantitativos para a avaliação de desempenho em relação a 33 requisitos de desempenho, sendo 15 referentes à segurança, 12 à eficiência e 6 à flexibilidade. Para ilustrar a aplicação deste protocolo, foi avaliado um conjunto de equipamentos disponíveis no mercado da Região Metropolitana de Porto Alegre - RS, de madeira, metálicos e mistos. Os resultados das avaliações desses equipamentos foram discutidos com representantes de empresas construtoras, especialistas em segurança no trabalho, projetistas e fornecedores de SPP, com a finalidade de propor melhorias nestes equipamentos. Os pontos fortes e fracos de cada sistema são discutidos com base nessas aplicações.

Rotational and peak torque stiffness of rugby shoes.

Science.gov (United States)

Ballal, Moez S; Usuelli, Federico Giuseppe; Montrasio, Umberto Alfieri; Molloy, Andy; La Barbera, Luigi; Villa, Tomaso; Banfi, Giuseppe

2014-09-01

Sports people always strive to avoid injury. Sports shoe designs in many sports have been shown to affect traction and injury rates. The aim of this study is to demonstrate the differing stiffness and torque in rugby boots that are designed for the same effect. Five different types of rugby shoes commonly worn by scrum forwards were laboratory tested for rotational stiffness and peak torque on a natural playing surface generating force patterns that would be consistent with a rugby scrum. The overall internal rotation peak torque was 57.75±6.26 Nm while that of external rotation was 56.55±4.36 Nm. The Peak internal and external rotational stiffness were 0.696±0.1 and 0.708±0.06 Nm/deg respectively. Our results, when compared to rotational stiffness and peak torques of football shoes published in the literature, show that shoes worn by rugby players exert higher rotational and peak torque stiffness compared to football shoes when tested on the same natural surfaces. There was significant difference between the tested rugby shoes brands. In our opinion, to maximize potential performance and lower the potential of non-contact injury, care should be taken in choosing boots with stiffness appropriate to the players main playing role. Copyright © 2014 Elsevier Ltd. All rights reserved.

Magnetic moment of inertia within the torque-torque correlation model.

Science.gov (United States)

Thonig, Danny; Eriksson, Olle; Pereiro, Manuel

2017-04-19

An essential property of magnetic devices is the relaxation rate in magnetic switching which strongly depends on the energy dissipation. This is described by the Landau-Lifshitz-Gilbert equation and the well known damping parameter, which has been shown to be reproduced from quantum mechanical calculations. Recently the importance of inertia phenomena have been discussed for magnetisation dynamics. This magnetic counterpart to the well-known inertia of Newtonian mechanics, represents a research field that so far has received only limited attention. We present and elaborate here on a theoretical model for calculating the magnetic moment of inertia based on the torque-torque correlation model. Particularly, the method has been applied to bulk itinerant magnets and we show that numerical values are comparable with recent experimental measurements. The theoretical analysis shows that even though the moment of inertia and damping are produced by the spin-orbit coupling, and the expression for them have common features, they are caused by very different electronic structure mechanisms. We propose ways to utilise this in order to tune the inertia experimentally, and to find materials with significant inertia dynamics.

A Computational Study on Hydrodynamic Torque Coefficients of a Butterfly Valve

International Nuclear Information System (INIS)

Lee, Do-Hwan; Park, Sung-Keun; Kang, Shin-Chul; Kim, Dae-Woong; Park, Ju-Yeop

2007-01-01

Butterfly valves have been widely used for on-off or control purposes in the process industry, since they provide quick opening and closing operation and good flow control characteristics. For the evaluation of the adequacy of valve operability and the actuator sizing, the required torque estimation is necessary. Since the principal contributing component of the require torque in the mid-stroke position is hydrodynamic torque, it is necessary to predict the torque properly under the actual flow conditions. The research on the prediction of the valve performance was led by EPRI (Electric Power Research Institute) in early 1990s. A performance prediction model was developed based on the experimental results and the free-streamline analysis by Sarpkaya. Recently, Kalsi Engineering carried out extended tests and developed the improved model. Variation of disk geometries and upstream flow conditions were tried to obtain accurate hydrodynamic torque coefficients. However, since the model is only commercially available, a general method to obtain hydrodynamic torque for butterfly valves is called for

Proposed torque optimized behavior for digital speed control of induction motors

Energy Technology Data Exchange (ETDEWEB)

Metwally, H.M.B.; El-Shewy, H.M.; El-Kholy, M.M. [Zagazig Univ., Dept. of Electrical Engineering, Zagazig (Egypt); Abdel-Kader, F.E. [Menoufyia Univ., Dept. of Electrical Engineering, Menoufyia (Egypt)

2002-09-01

In this paper, a control strategy for speed control of induction motors with field orientation is proposed. The proposed method adjusts the output voltage and frequency of the converter to operate the motor at the desired speed with maximum torque per ampere at all load torques keeping the torque angle equal to 90 deg. A comparison between the performance characteristics of a 2 hp induction motor using three methods of speed control is presented. These methods are the proposed method, the direct torque control method and the constant V/f method. The comparison showed that better performance characteristics are obtained using the proposed speed control strategy. A computer program, based on this method, is developed. Starting from the motor parameters, the program calculates a data set for the stator voltage and frequency required to obtain maximum torque per ampere at any motor speed and load torque. This data set can be used by the digital speed control system of induction motors. (Author)

Minimization of torque ripple in ferrite-assisted synchronous reluctance motors by using asymmetric stator

Science.gov (United States)

Xu, Meimei; Liu, Guohai; Zhao, Wenxiang; Aamir, Nazir

2018-05-01

Torque ripple is one of the important issues for ferrite assisted synchronous reluctance motors (FASRMs). In this paper, an asymmetrical stator is proposed for the FASRM to reduce its torque ripple. In the proposed FASRM, an asymmetrical stator is designed by appropriately choosing the angle of the slot-opening shift. Meanwhile, its analytical torque expressions are derived. The results show that the proposed FASRM has an effective reduction in the cogging torque, reluctance torque ripple and total torque ripple. Moreover, it is easy to implement while the average torque is not sacrificed.

Torque converter transient characteristics prediction using computational fluid dynamics

International Nuclear Information System (INIS)

Yamaguchi, T; Tanaka, K

2012-01-01

The objective of this research is to investigate the transient torque converter performance used in an automobile. A new technique in computational fluid dynamics is introduced, which includes the inertia of the turbine in a three dimensional simulation of the torque converter during a launch condition. The simulation results are compared to experimental test data with good agreement across the range of data. In addition, the simulated flow structure inside the torque converter is visualized and compared to results from a steady-state calculation.

EFEITO DA BANDAGEM FUNCIONAL NO MÚSCULO RETO FEMORAL EM INDIVÍDUOS HEMIPARÉTICOS ESPÁSTICOS

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Andressa Caroline Machuca Felix

2017-05-01

Full Text Available A bandagem funcional, é o nome dado a um tipo de banda adesiva desenvolvida no Japão em 1973, por Kenzo Kase. O paciente que tem como sequela à Hemiparesia espástica apresenta seus músculos rígidos e fracos. Objetivos: O objetivo principal do trabalho é observar o efeito da fita de bandagem elástica no músculo reto femoral em pacientes com sequela de Hemiparesia espástica, e aferir seu torque antes e após aplicação com o Dinamômetro isocinético computadorizado Cybex® (Biodex System®. Metodologia: Foi selecionado um grupo de 6 indivíduos com idade entre 40-80 anos, que apresentam sequelas de hemiparesia espástica. Neles foram avaliados a força do músculo reto femoral, em seguida estes indivíduos foram subdivididos em dois grupos. No Grupo 1: Em 3 indivíduos foi aplicada bandagem de forma inibitória no músculo reto femoral; No Grupo 2: Em 3 indivíduos foi aplicada a bandagem para ativação no músculo reto femoral. Resultados: Foi evidenciado estatisticamente um aumento no valor da porcentagem na média da avaliação inicial e a avaliação final de forma inibitória em aproximadamente 1,84% e, de forma ativa em aproximadamente 9,81%.

Torque characteristics of a 122-centimeter butterfly valve with a hydro/pneumatic actuator

Science.gov (United States)

Lin, F. N.; Moore, W. I.; Lundy, F. E.

1981-01-01

Actuating torque data from field testing of a 122-centimeter (48 in.) butterfly valve with a hydro/pneumatic actuator is presented. The hydraulic cylinder functions as either a forward or a reverse brake. Its resistance torque increases when the valve speeds up and decreases when the valve slows down. A reduction of flow resistance in the hydraulic flow path from one end of the hydraulic cylinder to the other will effectively reduce the hydraulic resistance torque and hence increase the actuating torque. The sum of hydrodynamic and friction torques (combined resistance torque) of a butterfly valve is a function of valve opening time. An increase in the pneumatic actuating pressure will result in a decrease in both the combined resistance torque and the actuator opening torque; however, it does shorten the valve opening time. As the pneumatic pressure increases, the valve opening time for a given configuration approaches an asymptotical value.

Torque Control of a Rehabilitation Teaching Robot Using Magneto-Rheological Fluid Clutches

Science.gov (United States)

Hakogi, Hokuto; Ohaba, Motoyoshi; Kuramochi, Naimu; Yano, Hidenori

A new robot that makes use of MR-fluid clutches for simulating torque is proposed to provide an appropriate device for training physical therapy students in knee-joint rehabilitation. The feeling of torque provided by the robot is expected to correspond to the torque performance obtained by physical therapy experts in a clinical setting. The torque required for knee-joint rehabilitation, which is a function of the rotational angle and the rotational angular velocity of a knee movement, is modeled using a mechanical system composed of typical spring-mass-damper elements. The robot consists of two MR-fluid clutches, two induction motors, and a feedback control system. In the torque experiments, output torque is controlled using the spring and damper coefficients separately. The values of these coefficients are determined experimentally. The experimental results show that the robot would be suitable for training physical therapy students to experience similar torque feelings as needed in a clinical situation.

Funciones psíquicas de las marcas corporales. // Psychic functions of body marking.

Directory of Open Access Journals (Sweden)

Margarita María Valencia Valencia.

2010-06-01

Full Text Available This article shows the results of a research titled Funciones psíquicas de las marcas corporales (Psychic Functions of Body Marking that analyses the tattoo, scarification and piercing boom in teenagers and young people. Its aim is to elucidate the body statute in our days. From the acknowledgment of the changes in status of human body throughout history and in different cultures, we investigate the special psychic functions of those practices and their symbolic implications, by using some psychoanalytical theories about body image and adolescence. // Este artículo presenta los resultados de la investigación Funciones psíquicas de las marcas corporales, que interroga el significado del auge de tatuajes, escarificaciones y piercings en adolescentes y jóvenes, con el fin de esclarecer el estatuto del cuerpo en la contemporaneidad. A partir de un reconocimiento de los cambios de estatus que el cuerpo ha tenido a través de la historia y las culturas, se indaga, con ayuda de las teorizaciones psicoanalíticas sobre lo corporal y la adolescencia, acerca de las funciones psíquicas particulares de dichas prácticas y su alcance simbolizador.

Prediction of a required dynamic torque for motor-operated butterfly valves

International Nuclear Information System (INIS)

Bae, J. H.; Lee, K. N.; Jeong, W. K.

2002-01-01

This study describes the methodology for predicting a required dynamic torque in motor-operated butterfly valves. The results of this methodology have been compared with test data for motor-operated butterfly valves in nuclear power plant. With the close review of test data and torque prediction, it is concluded that the prediction methodology is conservative to predict a required dynamic torque of motor-operated butterfly valves. In addition, the information of correct differential pressure is vital to predict a required dynamic torque of motor-operated butterfly valves

Reflex and Non-Reflex Torque Responses to Stretch of the Human Knee Extensors

National Research Council Canada - National Science Library

Mrachacz-Kersting, N

2001-01-01

.... The quadriceps muscles were stretched at various background torques, produced either voluntarily or electrically and thus the purely reflex-mediated torque could be calculated. The contribution of the reflex mediated stiffness initially low, increased with increasing background torques for the range of torques investigated.

REFLEXOS DAS CAPACIDADES MERCADOLÓGICAS NO DESEMPENHO: HOTELARIA EXECUTIVA

Directory of Open Access Journals (Sweden)

Deosir Flávio Lobo de Castro Júnior

2016-03-01

Full Text Available O objetivo deste artigo é analisar a relação entre as capacidades mercadológicas e o desempenho dos hotéis executivos em Santa Catarina. Para isto se faz necessário, identificar as variáveis relacionadas as capacidades mercadológicas, observar as variáveis relacionadas ao desempenho na hotelaria executiva e especificar as características do setor da hotelaria executiva. A metodologia empregada na pesquisa foi composta pela abordagem, quantitativo-descritivo, que é o caso da pesquisa descritiva, havendo teste de hipótese, o tipo e estratégia utilizado foi utilizado a survey, o universo e amostra foram os hotéis executivos de Santa Catarina., Após as técnicas estatísticas descritivas de análise do material empírico que foram utilizadas e pela análise multivariada de dados. As conclusões apontam para esta relação e a importância do aumento das capacidades mercadológicas da organização em ambiente dinâmico.

Riscos de cont?gio em tuberculose entre funcion?rios em um hospital universit?rio no munic?pio de Niter?i - Rio de Janeiro

OpenAIRE

Couto, Ingrid Ramos Reis

2012-01-01

Problema: O aparecimento de casos de adoecimentos por tuberculose entre os funcion?rios do HUAP. Objetivos: Analisar os fatores de risco para tuberculose e o perfil epidemiol?gico dos funcion?rios do HUAP/UFF com resultado da prova tubercul?nica ? 10 mm no per?odo de 2007 a junho de 2011; - Investigar os casos de adoecimento por tuberculose em funcion?rios do HUAP/UFF no per?odo de janeiro de 2004 a julho de 2011; - Identificar a poss?vel associa??o entre o perfil epidemiol?gico dos funcion?r...

Instantaneous flywheel torque of IC engine grey-box identification

Science.gov (United States)

Milašinović, A.; Knežević, D.; Milovanović, Z.; Škundrić, J.

2018-01-01

In this paper a mathematical model developed for the identification of excitation torque acting on the IC engine flywheel is presented. The excitation torque gained through internal combustion of the fuel in the IC engine is transmitted from the flywheel to the transmission. The torque is not constant but variable and is a function of the crank angle. The verification of the mathematical model was done on a 4-cylinder 4-stroke diesel engine for which the in-cylinder pressure was measured in one cylinder and the instantaneous angular speed of the crankshaft at its free end. The research was conducted on a hydraulic engine brake. Inertial forces of all rotational parts, from flywheel to the turbine wheel of the engine brake, are acting on the flywheel due to the nonuniform motion of the flywheel. It is known from the theory of turbomachinery that the torque on the hydraulic brake is a quadratic function of angular speed. Due to that and the variable angular speed of the turbine wheel of the engine brake, the torque during one engine cycle is also variable. The motivation for this research was the idea (intention) to determine the instantaneous torque acting on the flywheel as a function of the crank angle with a mathematical model without any measuring and based on this to determine the quality of work of specific cylinders of the multi-cylinder engine. The crankshaft was considered elastic and also its torsional vibrations were taken into account.

Desempenho da Inovação de Produto: Teste de uma Escala para Aplicação em PME's

Directory of Open Access Journals (Sweden)

Nilvane Boehm Manthey

2016-12-01

Full Text Available A crescente pesquisa em gestão da inovação incita a necessidade de medir o desempenho proporcionado pelas variadas ações de inovação. No entanto a medição de desempenho da inovação, especialmente da inovação de produto, encontra-se ainda dispersa em uma variedade de modos, seja quanto as suas entradas e saídas e/ou ainda quanto a utilizar-se dados objetivos e subjetivos. A replicação de métodos tradicionais de mensuração do desempenho da inovação de produto que não consideram os diversos resultados da inovação de produtos para a organização, agrava a questão de medida do desempenho da inovação de produto. Neste sentido, o presente estudo visa avaliar a validade e confiabilidade de uma escala multidimensional proposta por Hanachi (2015 que considera medidas de percepção, bem como o desempenho da inovação de produto como um output, para aplicação em Pequenas e Médias Empresas (PME do setor industrial. A pesquisa é de caráter descritivo, de tipo survey e com corte transversal. A aplicação da escala de desempenho da inovação do produto foi realizada com 94 gestores de pequenas e médias indústrias do setor têxtil. Para a realização da análise empregou-se os softwares Statistica® e SPSS 2.0 onde se realizaram os testes de unidimensionalidade e confiabilidade dos constructos e posterior aplicação da análise fatorial. O resultado aponta à pertinência e aplicabilidade da escala proposta e disponibiliza uma escala válida para novos estudos que buscarem relacionar desempenho da inovação de produto com outros construtos apresentados na literatura. 

Mechanics of torque generation in the bacterial flagellar motor.

Science.gov (United States)

Mandadapu, Kranthi K; Nirody, Jasmine A; Berry, Richard M; Oster, George

2015-08-11

The bacterial flagellar motor (BFM) is responsible for driving bacterial locomotion and chemotaxis, fundamental processes in pathogenesis and biofilm formation. In the BFM, torque is generated at the interface between transmembrane proteins (stators) and a rotor. It is well established that the passage of ions down a transmembrane gradient through the stator complex provides the energy for torque generation. However, the physics involved in this energy conversion remain poorly understood. Here we propose a mechanically specific model for torque generation in the BFM. In particular, we identify roles for two fundamental forces involved in torque generation: electrostatic and steric. We propose that electrostatic forces serve to position the stator, whereas steric forces comprise the actual "power stroke." Specifically, we propose that ion-induced conformational changes about a proline "hinge" residue in a stator α-helix are directly responsible for generating the power stroke. Our model predictions fit well with recent experiments on a single-stator motor. The proposed model provides a mechanical explanation for several fundamental properties of the flagellar motor, including torque-speed and speed-ion motive force relationships, backstepping, variation in step sizes, and the effects of key mutations in the stator.

Planetary Torque in 3D Isentropic Disks

International Nuclear Information System (INIS)

Fung, Jeffrey; Masset, Frédéric; Velasco, David; Lega, Elena

2017-01-01

Planetary migration is inherently a three-dimensional (3D) problem, because Earth-size planetary cores are deeply embedded in protoplanetary disks. Simulations of these 3D disks remain challenging due to the steep resolution requirements. Using two different hydrodynamics codes, FARGO3D and PEnGUIn, we simulate disk–planet interaction for a one to five Earth-mass planet embedded in an isentropic disk. We measure the torque on the planet and ensure that the measurements are converged both in resolution and between the two codes. We find that the torque is independent of the smoothing length of the planet’s potential ( r s ), and that it has a weak dependence on the adiabatic index of the gaseous disk ( γ ). The torque values correspond to an inward migration rate qualitatively similar to previous linear calculations. We perform additional simulations with explicit radiative transfer using FARGOCA, and again find agreement between 3D simulations and existing torque formulae. We also present the flow pattern around the planets that show active flow is present within the planet’s Hill sphere, and meridional vortices are shed downstream. The vertical flow speed near the planet is faster for a smaller r s or γ , up to supersonic speeds for the smallest r s and γ in our study.

Are torque values of preadjusted brackets precise?

Directory of Open Access Journals (Sweden)

Alessandra Motta Streva

Full Text Available OBJECTIVE: The aim of the present study was to verify the torque precision of metallic brackets with MBT prescription using the canine brackets as the representative sample of six commercial brands. MATERIAL AND METHODS: Twenty maxillary and 20 mandibular canine brackets of one of the following commercial brands were selected: 3M Unitek, Abzil, American Orthodontics, TP Orthodontics, Morelli and Ortho Organizers. The torque angle, established by reference points and lines, was measured by an operator using an optical microscope coupled to a computer. The values were compared to those established by the MBT prescription. RESULTS: The results showed that for the maxillary canine brackets, only the Morelli torque (-3.33º presented statistically significant difference from the proposed values (-7º. For the mandibular canines, American Orthodontics (-6.34º and Ortho Organizers (-6.25º presented statistically significant differences from the standards (-6º. Comparing the brands, Morelli presented statistically significant differences in comparison with all the other brands for maxillary canine brackets. For the mandibular canine brackets, there was no statistically significant difference between the brands. CONCLUSIONS: There are significant variations in torque values of some of the brackets assessed, which would clinically compromise the buccolingual positioning of the tooth at the end of orthodontic treatment.

Space Suit Joint Torque Testing

Science.gov (United States)

Valish, Dana J.

2011-01-01

In 2009 and early 2010, a test was performed to quantify the torque required to manipulate joints in several existing operational and prototype space suits in an effort to develop joint torque requirements appropriate for a new Constellation Program space suit system. The same test method was levied on the Constellation space suit contractors to verify that their suit design meets the requirements. However, because the original test was set up and conducted by a single test operator there was some question as to whether this method was repeatable enough to be considered a standard verification method for Constellation or other future space suits. In order to validate the method itself, a representative subset of the previous test was repeated, using the same information that would be available to space suit contractors, but set up and conducted by someone not familiar with the previous test. The resultant data was compared using graphical and statistical analysis and a variance in torque values for some of the tested joints was apparent. Potential variables that could have affected the data were identified and re-testing was conducted in an attempt to eliminate these variables. The results of the retest will be used to determine if further testing and modification is necessary before the method can be validated.

Production Experiences with the Cray-Enabled TORQUE Resource Manager

Energy Technology Data Exchange (ETDEWEB)

Ezell, Matthew A [ORNL; Maxwell, Don E [ORNL; Beer, David [Adaptive Computing

2013-01-01

High performance computing resources utilize batch systems to manage the user workload. Cray systems are uniquely different from typical clusters due to Cray s Application Level Placement Scheduler (ALPS). ALPS manages binary transfer, job launch and monitoring, and error handling. Batch systems require special support to integrate with ALPS using an XML protocol called BASIL. Previous versions of Adaptive Computing s TORQUE and Moab batch suite integrated with ALPS from within Moab, using PERL scripts to interface with BASIL. This would occasionally lead to problems when all the components would become unsynchronized. Version 4.1 of the TORQUE Resource Manager introduced new features that allow it to directly integrate with ALPS using BASIL. This paper describes production experiences at Oak Ridge National Laboratory using the new TORQUE software versions, as well as ongoing and future work to improve TORQUE.

Torque Modeling and Control of a Variable Compression Engine

OpenAIRE

Bergström, Andreas

2003-01-01

The SAAB variable compression engine is a new engine concept that enables the fuel consumption to be radically cut by varying the compression ratio. A challenge with this new engine concept is that the compression ratio has a direct influence on the output torque, which means that a change in compression ratio also leads to a change in the torque. A torque change may be felt as a jerk in the movement of the car, and this is an undesirable effect since the driver has no control over the compre...

Intrinsic nonadiabatic topological torque in magnetic skyrmions and vortices

KAUST Repository

Akosa, Collins Ashu; Ndiaye, Papa Birame; Manchon, Aurelien

2017-01-01

We propose that topological spin currents flowing in topologically nontrivial magnetic textures, such as magnetic skyrmions and vortices, produce an intrinsic nonadiabatic torque of the form Tt∼[(∂xm×∂ym)·m]∂ym. We show that this torque, which is absent in one-dimensional domain walls and/or nontopological textures, is responsible for the enhanced nonadiabaticity parameter observed in magnetic vortices compared to one-dimensional textures. The impact of this torque on the motion of magnetic skyrmions is expected to be crucial, especially to determine their robustness against defects and pinning centers.

Intrinsic nonadiabatic topological torque in magnetic skyrmions and vortices

KAUST Repository

Akosa, Collins Ashu

2017-03-01

We propose that topological spin currents flowing in topologically nontrivial magnetic textures, such as magnetic skyrmions and vortices, produce an intrinsic nonadiabatic torque of the form Tt∼[(∂xm×∂ym)·m]∂ym. We show that this torque, which is absent in one-dimensional domain walls and/or nontopological textures, is responsible for the enhanced nonadiabaticity parameter observed in magnetic vortices compared to one-dimensional textures. The impact of this torque on the motion of magnetic skyrmions is expected to be crucial, especially to determine their robustness against defects and pinning centers.

Optimal Spacecraft Attitude Control Using Aerodynamic Torques

Science.gov (United States)

2007-03-01

His design resembles a badminton shuttlecock and “uses passive aerodynamic drag torques to stabilize pitch and yaw” and active magnetic torque...Ravindran’s and Hughes’ ‘arrow-like’ design. Psiaki notes that “this arrow concept has been modified to become a badminton shuttlecock-type design...panels were placed to the rear of the center-of-mass, similar to a badminton shuttlecock, to provide passive stability about the pitch and yaw axes

Peak torque and rate of torque development influence on repeated maximal exercise performance: contractile and neural contributions.

Science.gov (United States)

Morel, Baptiste; Rouffet, David M; Saboul, Damien; Rota, Samuel; Clémençon, Michel; Hautier, Christophe A

2015-01-01

Rapid force production is critical to improve performance and prevent injuries. However, changes in rate of force/torque development caused by the repetition of maximal contractions have received little attention. The aim of this study was to determine the relative influence of rate of torque development (RTD) and peak torque (T(peak)) on the overall performance (i.e. mean torque, T(mean)) decrease during repeated maximal contractions and to investigate the contribution of contractile and neural mechanisms to the alteration of the various mechanical variables. Eleven well-trained men performed 20 sets of 6-s isokinetic maximal knee extensions at 240° · s(-1), beginning every 30 seconds. RTD, T(peak) and T(mean) as well as the Rate of EMG Rise (RER), peak EMG (EMG(peak)) and mean EMG (EMG(mean)) of the vastus lateralis were monitored for each contraction. A wavelet transform was also performed on raw EMG signal for instant mean frequency (if(mean)) calculation. A neuromuscular testing procedure was carried out before and immediately after the fatiguing protocol including evoked RTD (eRTD) and maximal evoked torque (eT(peak)) induced by high frequency doublet (100 Hz). T(mean) decrease was correlated to RTD and T(peak) decrease (R(²) = 0.62; p<0.001; respectively β=0.62 and β=0.19). RER, eRTD and initial if(mean) (0-225 ms) decreased after 20 sets (respectively -21.1 ± 14.1, -25 ± 13%, and ~20%). RTD decrease was correlated to RER decrease (R(²) = 0.36; p<0.05). The eT(peak) decreased significantly after 20 sets (24 ± 5%; p<0.05) contrary to EMG(peak) (-3.2 ± 19.5 %; p=0.71). Our results show that reductions of RTD explained part of the alterations of the overall performance during repeated moderate velocity maximal exercise. The reductions of RTD were associated to an impairment of the ability of the central nervous system to maximally activate the muscle in the first milliseconds of the contraction.

PROPUESTA METODOLÓGICA PARA DESARROLLAR UN PROGRAMA CON PROGRAMACIÓN ESTRUCTURADA A PARTIR DEL PARADIGMA FUNCIONAL

Directory of Open Access Journals (Sweden)

Omar Iván Trejos Buriticá

2013-01-01

Full Text Available El presente artículo es producto de un Proyecto de Investigación 1 desarrollado en el área de la programación de computadores y su relación con los procesos de aprendizaje que se involucran alrededor de ella. En este artículo se plantea una metodología para el desarrollo de programas que se basa en la programación estructurada, pero tomando como base los conceptos centrales del Paradigma Funcional para su desarrollo. Se busca con esta propuesta metodológica enfrentar y solucionar los tres grandes problemas de la programación e igualmente, se persigue la simplificación de la programación estructurada a partir de la utilización de funciones. Se acude a una concepción general del programa a realizar y se va desglosando poco a poco, al tiempo que se construyen funciones que cumplan con los micro-objetivos planteados. Se ha encontrado que, para los estudiantes, es una forma muy sencilla y simplificada de concebir tanto el paradigma estructurado como el paradigma funcional y que su relación facilita la comprensión de los conceptos asociados a dichos paradigmas.

Spin Torque Oscillator for High Performance Magnetic Memory

Directory of Open Access Journals (Sweden)

Rachid Sbiaa

2015-06-01

Full Text Available A study on spin transfer torque switching in a magnetic tunnel junction with perpendicular magnetic anisotropy is presented. The switching current can be strongly reduced under a spin torque oscillator (STO, and its use in addition to the conventional transport in magnetic tunnel junctions (MTJ should be considered. The reduction of the switching current from the parallel state to the antiparallel state is greater than in  the opposite direction, thus minimizing the asymmetry of the resistance versus current in the hysteresis loop. This reduction of both switching current and asymmetry under a spin torque oscillator occurs only during the writing process and does not affect the thermal stability of the free layer.

Biomechanical evaluation of macro and micro designed screw-type implants: an insertion torque and removal torque study in rabbits.

Science.gov (United States)

Chowdhary, Ramesh; Jimbo, Ryo; Thomsen, Christian; Carlsson, Lennart; Wennerberg, Ann

2013-03-01

To investigate the combined effect of macro and pitch shortened threads on primary and secondary stability during healing, but before dynamic loading. Two sets of turned implants with different macro geometry were prepared. The test group possessed pitch shortened threads in between the large threads and the control group did not have thread alterations. The two implant groups were placed in both femur and tibiae of 10 lop-eared rabbits, and at the time of implant insertion, insertion torques were recorded. After 4 weeks, all implants were subjected to removal torque tests. The insertion torque values for the control and test groups for the tibia were 15.7 and 20.6 Ncm, respectively, and for the femur, 11.8, and 12.8 Ncm respectively. The removal torque values for the control and test groups in the tibia were 7.9 and 9.1 Ncm, respectively, and for the femur, 7.9 and 7.7 Ncm respectively. There was no statistically significant difference between the control and test groups. Under limited dynamic load, the addition of pitch shortened threads did not significantly improve either the primary or the secondary stability of the implants in bone. © 2011 John Wiley & Sons A/S.

Dor neuropática central após lesão medular traumática: capacidade funcional e aspectos sociais

OpenAIRE

Vall, Janaina; Braga, Violante Augusta Batista

2005-01-01

Estudo de caso comparativo com o objetivo de avaliar a capacidade funcional e os aspectos sociais de dois pacientes, ambos com lesão medular traumática, sem e com dor neuropática central associada, respectivamente. Para avaliar a capacidade funcional, foi utilizado como instrumento o Functional Independence Measure ou Escala de Independência Funcional. E para avaliar os aspectos sociais foi construído o ecomapa de cada paciente, preconizado pelo modelo Calgary de avaliação de famílias. Ambos ...

The overuse of the implant motor: effect on the output torque in overloading condition.

Science.gov (United States)

Lee, Du-Hyeong; Cho, Sung-Am; Lee, Cheong-Hee; Lee, Kyu-Bok

2015-06-01

The overloading of the motor affects its performance. The output torque of the implant motor under overloading condition has not been reported. The purpose of this study was to determine the reliability and the tendency of the output torque when an implant motor is consecutively used. Three implant motors were evaluated: SurgicXT/X-SG20L (NSK), INTRAsurg300/CL3-09 (KaVo), and XIP10/CRB26LX (Saeshin). The output torque was measured using an electronic torque gauge fixed with jigs. For the 40 and 50 Ncm torque settings, 300 measurements were taken at 30 rpm. Repeated measures of analysis of variance (ANOVA) and one-way ANOVA were used to compare the torque values within each group and between the groups. As repeating measures, the output torque values decreased gradually compared with the baseline. In within-group analysis, the different torque value from the first measurement appeared earliest in NSK motor, followed in order by Saeshin and KaVo motors. NSK motor showed a different torque decrease between 40 and 50 Ncm settings (p torque at the 6, 8, 9, and 10 repeat counts (p torque decreases when the surgical motor is continuously used. The NSK motor showed more significant decreases in torque than KaVo and Saeshin motors in overloading condition. © 2014 Wiley Periodicals, Inc.

Spin Torques in Systems with Spin Filtering and Spin Orbit Interaction

KAUST Repository

Ortiz Pauyac, Christian

2016-06-19

In the present thesis we introduce the reader to the field of spintronics and explore new phenomena, such as spin transfer torques, spin filtering, and three types of spin-orbit torques, Rashba, spin Hall, and spin swapping, which have emerged very recently and are promising candidates for a new generation of memory devices in computer technology. A general overview of these phenomena is presented in Chap. 1. In Chap. 2 we study spin transfer torques in tunnel junctions in the presence of spin filtering. In Chap. 3 we discuss the Rashba torque in ferromagnetic films, and in Chap. 4 we study spin Hall effect and spin swapping in ferromagnetic films, exploring the nature of spin-orbit torques based on these mechanisms. Conclusions and perspectives are summarized in Chap. 5.

O efeito da prescrição de cadeira de rodas de basquetebol sobre o desempenho esportivo

Directory of Open Access Journals (Sweden)

Giane Francine Garcia de Moraes

2011-12-01

Full Text Available Foi analisado o desempenho esportivo de jogadores de basquetebol com utilização de cadeiras de rodas prescritas (específicas e não-prescritas (genéricas de acordo com as características de cada atleta. Seis participantes desempenharam testes de velocidade (20 m com e sem bola e de agilidade (sem bola. Escalas de percepção de esforço e de conforto foram utilizadas após a realização dos testes. Foram verificados melhores desempenho e conforto nos testes realizados com a utilização das cadeiras prescritas. Foi sugerido o uso de cadeiras prescritas especificamente para cada atleta, a fim de otimizar o desempenho e o conforto para a prática do basquetebol em cadeira de rodas.

Avaliação do desempenho isocinético da musculatura extensora e flexora do joelho de atletas de futsal em membro dominante e não dominante

Directory of Open Access Journals (Sweden)

Aparecido Pimentel Ferreira

2010-09-01

Full Text Available OBJETIVO: avaliar o desempenho isocinético da musculatura extensora e flexora do joelho em atletas de futsal nos membros DO e ND. METODOLOGIA: participaram 23 atletas, com idade de 27,1 ± 3,6 anos, massa corporal 72,7 ± 12,6kg e estatura 1,75 ± 6,7m. Realizou-se 6 repetições máximas nas velocidades de 60, 120, 180 e 300º.s-1, em ordem crescente no dinamômetro isocinético. Avaliou-se pico de torque (PT, PT normalizado (PTN, PT médio (PTM, potência média (PM, trabalho total da repetição máxima (TTRM e quantidade de trabalho total (QTT. RESULTADOS: no movimento de flexão, a PM 180º.s-1 foi 6,7% maior no membro DO (p < 0,05. No movimento de extensão, o ND superou o DO (p < 0,05, sendo: PT 60º.s-1 (+7,6%, PTN 60º.s-1 (+7,0%, TTRM 120º.s-1 (+6,0%, PM 60º.s-1 (+6,6% e 120º.s-1 (+5,2%, QTT 60º.s-1 (+6,9% e 120º.s-1 (+7,5% e PTM 60º.s-1 (+7,3% e 120º.s-1 (+5,2%. Exceto pela PM e TTRM, todas as variáveis apresentaram maior desempenho a 60º.s-1. CONCLUSÃO: apesar das diferenças entre DO e ND, essas diferenças não os predispõem à incidência de lesões.

Funciones sociales del consumo: un caso extremo

OpenAIRE

JOSÉ CASTILLO CASTILLO

1994-01-01

El consumo religioso de reliquías de santos durante la edad media cumple semejantes funciones sociales para su época que el consumo economico de objetos para la nuestra: El de reforzar real y simbólicamente las estructuras de prestigio, riqueza y poder de sus respectivas sociedades. El ámbito de la sociología del consumo no se circunscribe a los estrechos límites de las llamadas sociedades de consumo de masas. en el presente caso, el estudio del pasado ilumina procesos sociales propios de nue...

Torque expression of 0.018 and 0.022 inch conventional brackets

NARCIS (Netherlands)

Sifakakis, I.; Pandis, N.; Makou, M.; Eliades, T.; Katsaros, C.; Bourauel, C.

2013-01-01

The aim of this study was to assess the effect of the moments generated with low- and high-torque brackets. Four different bracket prescription-slot combinations of the same bracket type (Mini Diamond(R) Twin) were evaluated: high-torque 0.018 and 0.022 inch and low-torque 0.018 and 0.022 inch.

Apply of torque method at rationalization of work

Directory of Open Access Journals (Sweden)

Bandurová Miriam

2001-03-01

Full Text Available Aim of the study was to analyse consumption of time for profession - cylinder grinder, by torque method.Method of torque following is used for detection of sorts and size of time slope, on detection of portion of individual sorts of time consumption and cause of time slope. By this way it is possible to find out coefficient of employment and recovery of workers in organizational unit. Advantage of torque survey is low costs on informations acquirement, non-fastidiousness per worker and observer, which is easy trained. It is mentally acceptable method for objects of survey.Finding and detection of reserves in activity of cylinders grinder result of torque was surveys. Loss of time presents till 8% of working time. In 5 - shift service and average occupiying of shift by 4,4 grinder ( from statistic information of service , loss at grinder of cylinders are for whole centre 1,48 worker.According presented information it was recommended to cancel one job place - grinder of cylinders - and reduce state about one grinder. Next job place isn't possible cancel, because grindery of cylinders must to adapt to the grind line by number of polished cylinders in shift and semi - finishing of polished cylinders can not be high for often changes in area of grinding and sortiment changes.By this contribution we confirmed convenience of exploitation of torque method as one of the methods using during the job rationalization.

Sistema judicial e desempenho da economia

OpenAIRE

Santos, Luís Máximo dos

2004-01-01

As instituições têm desempenhado desde sempre um papel importante na análise económica, opondo-se por vezes à teoria económica neoclássica e ao conceito do homo economicus. Actualmente considera-se que as instituições são um factor de grande importância para o desempenho das economias, em particular nos processos de crescimento e de desenvolvimento económico, a tal ponto que o Relatório sobre o Desenvolvimento Mundial de 2002 do Banco Mundial se intitula “Buiding Institutions for Markets”. No...

Magnetic torque transferring study for bulk High-Tc superconductors and permanent magnets

International Nuclear Information System (INIS)

Wongsatanawarid, A; Suzuki, A; Seki, H; Murakami, M

2009-01-01

The torque transferring mechanism taking place in a superconducting mixer design has been studied. Several coupling magnetic arrangements were investigated for more details in the engineering design. A bulk superconductor sample was used to study the torque forces for various cooling gaps, and the twist angle dependence was also monitored for the rotational stiffness in stability. The experimental data with four permanent magnet configurations have been studied in the present work. The maximum torque forces are summarized for usage of engineering design with various gaps. The torque/gap characteristics for four configurations were also measured for the optimisation of the torque at a designed operating gap.

Intraband and interband spin-orbit torques in noncentrosymmetric ferromagnets

KAUST Repository

Li, Hang; Gao, H.; Zâ rbo, Liviu P.; Vý borný , K.; Wang, Xuhui; Garate, Ion; Dogan, Fatih; Čejchan, A.; Sinova, Jairo; Jungwirth, T.; Manchon, Aurelien

2015-01-01

Intraband and interband contributions to the current-driven spin-orbit torque in magnetic materials lacking inversion symmetry are theoretically studied using the Kubo formula. In addition to the current-driven fieldlike torque TFL=τFLm×uso (uso being a unit vector determined by the symmetry of the spin-orbit coupling), we explore the intrinsic contribution arising from impurity-independent interband transitions and producing an anti-damping-like torque of the form TDL=τDLm×(uso×m). Analytical expressions are obtained in the model case of a magnetic Rashba two-dimensional electron gas, while numerical calculations have been performed on a dilute magnetic semiconductor (Ga,Mn)As modeled by the Kohn-Luttinger Hamiltonian exchange coupled to the Mn moments. Parametric dependencies of the different torque components and similarities to the analytical results of the Rashba two-dimensional electron gas in the weak disorder limit are described.

Knudsen torque: A rotational mechanism driven by thermal force

Science.gov (United States)

Li, Qi; Liang, Tengfei; Ye, Wenjing

2014-09-01

Thermally induced mechanical loading has been shown to have significant effects on micro- and nano-objects immersed in a gas with a nonuniform temperature field. While the majority of existing studies and related applications focus on forces, we investigate the torque, and thus the rotational motion, produced by such a mechanism. Our study has found that a torque can be induced if the configuration of the system is asymmetric. In addition, both the magnitude and the direction of the torque depend highly on the system configuration, indicating the possibility of manipulating the rotational motion via geometrical design. Based on this feature, two types of rotational micromotor that are of practical importance, namely pendulum motor and unidirectional motor, are designed. The magnitude of the torque at Kn =0.5 can reach to around 2nN×μm for a rectangular microbeam with a length of 100μm.

Intraband and interband spin-orbit torques in noncentrosymmetric ferromagnets

KAUST Repository

Li, Hang

2015-04-01

Intraband and interband contributions to the current-driven spin-orbit torque in magnetic materials lacking inversion symmetry are theoretically studied using the Kubo formula. In addition to the current-driven fieldlike torque TFL=τFLm×uso (uso being a unit vector determined by the symmetry of the spin-orbit coupling), we explore the intrinsic contribution arising from impurity-independent interband transitions and producing an anti-damping-like torque of the form TDL=τDLm×(uso×m). Analytical expressions are obtained in the model case of a magnetic Rashba two-dimensional electron gas, while numerical calculations have been performed on a dilute magnetic semiconductor (Ga,Mn)As modeled by the Kohn-Luttinger Hamiltonian exchange coupled to the Mn moments. Parametric dependencies of the different torque components and similarities to the analytical results of the Rashba two-dimensional electron gas in the weak disorder limit are described.

Torque fluctuations caused by upstream mean flow and turbulence

Science.gov (United States)

Farr, T. D.; Hancock, P. E.

2014-12-01

A series of studies are in progress investigating the effects of turbine-array-wake interactions for a range of atmospheric boundary layer states by means of the EnFlo meteorological wind tunnel. The small, three-blade model wind turbines drive 4-quadrant motor-generators. Only a single turbine in neutral flow is considered here. The motor-generator current can be measured with adequate sensitivity by means of a current sensor allowing the mean and fluctuating torque to be inferred. Spectra of torque fluctuations and streamwise velocity fluctuations ahead of the rotor, between 0.1 and 2 diameters, show that only the large-scale turbulent motions contribute significantly to the torque fluctuations. Time-lagged cross-correlation between upstream velocity and torque fluctuations are largest over the inner part of the blade. They also show the turbulence to be frozen in behaviour over the 2 diameters upstream of the turbine.

Hip joint torques during the golf swing of young and senior healthy males.

Science.gov (United States)

Foxworth, Judy L; Millar, Audrey L; Long, Benjamin L; Way, Michael; Vellucci, Matthew W; Vogler, Joshua D

2013-09-01

Descriptive, laboratory study. To compare the 3-D hip torques during a golf swing between young and senior healthy male amateur golfers. The secondary purpose was to compare the 3-D hip joint torques between the trail leg and lead leg. The generation of hip torques from the hip musculature is an important aspect of the golf swing. Golf is a very popular activity, and estimates of hip torques during the golf swing have not been reported. Twenty healthy male golfers were divided into a young group (mean ± SD age, 25.1 ± 3.1 years) and a senior group (age, 56.9 ± 4.7 years). All subjects completed 10 golf swings using their personal driver. A motion capture system and force plates were used to obtain kinematic and kinetic data. Inverse dynamic analyses were used to calculate 3-D hip joint torques of the trail and lead limbs. Two-way analyses of covariance (group by leg), with club-head velocity as a covariate, were used to compare peak hip torques between groups and limbs. Trail-limb hip external rotator torque was significantly greater in the younger group compared to the senior group, and greater in the trail leg versus the lead leg. When adjusting for club-head velocity, young and senior healthy male amateur golfers generated comparable hip torques during a golf swing, with the exception of the trail-limb hip external rotator torque. The largest hip torque found was the trail-limb hip extensor torque.

Cotas e desempenho acadêmico na UFBA: um estudo a partir dos coeficientes de rendimento

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Adriano de Lemos Alves Peixoto

Full Text Available Resumo: Um debate recorrente em torno das cotas na universidade é a possibilidade do cotista obter rendimento satisfatório a despeito das diferenças no seu processo de formação anterior ao ingresso na Universidade. O objetivo deste estudo é comparar o desempenho de alunos cotistas e não cotistas da Universidade Federal da Bahia (UFBA, reunindo evidências que possam embasar ações institucionais no sentido de assegurar sólida formação a todos os seus alunos. A amostra foi por composta por todos os alunos ativos (N=26.175 matriculados. As análises indicam desempenho superior de não cotistas, sendo a magnitude da diferença 6,81% (F=348,114, p<.000 quando os dois grupos são diretamente comparados. Quando separados por área de conhecimento, os cotistas apresentam desempenho superior em cursos das áreas de artes e humanidades de média e baixa concorrência. O déficit na formação básica, principalmente no domínio da matemática, aparece como um possível fator de influência nesta diferença de desempenho. Os resultados sugerem um fenômeno complexo e multifacetado. Para além das disputas ideológicas é preciso intervir nesta disparidade para uma efetiva inclusão dos cotistas na universidade.

Torque loss of different abutment sizes before and after cyclic loading.

Science.gov (United States)

Moris, Izabela Cristina; Faria, Adriana Cláudia; Ribeiro, Ricardo Faria; Rodrigues, Renata Cristina

2015-01-01

The aim of this study was to compare 3.8- and 4.8-mm abutments submitted to simulations of masticatory cycles to examine whether abutment diameter and cemented vs screw-retained crowns affect torque loss of the abutments and crowns. Forty implant/abutment sets were divided into the following groups (n = 10 in each group): (1) G4.8S included 4.8-mm abutment with screw-retained crown; (2) G4.8C included 4.8-mm abutment with cemented crown; (3) G3.8S included 3.8-mm abutment with screw-retained crown; and (4) G3.8C included 3.8-mm abutment with cemented crown. All abutments were tightened with torque values of 20 Ncm, and 10 Ncm for screw-retained crowns. Torque loss was measured before and after cycling loading (300,000 cycles). Torque loss of screw-retained crowns significantly increased after cycling in abutments of groups G3.8S (P ≤ .05) and G4.8S (P = .001). No difference was noted between the abutments before cycling (P = .735), but G3.8S abutments presented greater torque loss than the other groups after cycling (P = .008). Significant differences were noted in the abutment torque loss before and after cycling loading only for the G3.8C group (P ≤ .05). The abutment diameter affects torque loss of screw-retained crowns and leads to failure during the test; mechanical cycling increases torque loss of abutment screw and screw-retained crowns.

Avaliação do desempenho energético de um grande edifício de serviços existente

OpenAIRE

Garrido, Diogo Emanuel da Silva

2013-01-01

Nesta dissertação pretende-se caracterizar o desempenho energético de um grande edifício de serviços existente, da tipologia ensino, avaliar e identificar potenciais medidas que melhorem aquele desempenho, permitindo, em complemento, determinar a sua classificação energética no âmbito da legislação vigente. A pertinência do estudo prende-se com a avaliação do desempenho energético dos edifícios e com o estudo de medidas de melhoria que permitam incrementar a eficiência energéti...

Maracujá: um alimento funcional?

Directory of Open Access Journals (Sweden)

Maria Luiza Zeraik

Full Text Available Este artigo é uma revisão bibliográfica sobre as espécies brasileiras de Passiflora (Passiflora edulis fo. flavicarpa O. Deg., P. alata Curtis e P. edulis fo. edulis. A maioria dos artigos da literatura focaliza somente as folhas de Passiflora, enquanto que esta revisão contém informações sobre a polpa, cascas e sementes dos frutos do maracujá, com destaque para a composição química, estudos nutricionais e farmacológicos. O enfoque nos frutos do maracujá fundamenta-se no amplo consumo do suco de maracujá (fresco ou industrializado no Brasil e também nas investigações em andamento para avaliar o seu potencial uso como alimento funcional.

Analytical calculation of the torque exerted between two perpendicularly magnetized magnets

Science.gov (United States)

Allag, H.; Yonnet, J.-P.; Latreche, M. E. H.

2011-04-01

Analytical expressions of the torque on cuboidal permanent magnets are given. The only hypothesis is that the magnetizations are rigid, uniform, and perpendicularly oriented. The analytical calculation is made by replacing magnetizations by distributions of magnetic charges on the magnet poles. The torque expressions are obtained using the Lorentz force method. The results are valid for any relative magnet position, and the torque can be obtained with respect to any reference point. Although these expressions seem rather complicated, they enable an extremely fast and accurate torque calculation on a permanent magnet in the presence of a magnetic field of another permanent magnet.

A flight simulator control system using electric torque motors

Science.gov (United States)

Musick, R. O.; Wagner, C. A.

1975-01-01

Control systems are required in flight simulators to provide representative stick and rudder pedal characteristics. A system has been developed that uses electric dc torque motors instead of the more common hydraulic actuators. The torque motor system overcomes certain disadvantages of hydraulic systems, such as high cost, high power consumption, noise, oil leaks, and safety problems. A description of the torque motor system is presented, including both electrical and mechanical design as well as performance characteristics. The system develops forces sufficiently high for most simulations, and is physically small and light enough to be used in most motion-base cockpits.

Shielding of External Magnetic Perturbations By Torque In Rotating Tokamak Plasmas

International Nuclear Information System (INIS)

Park, Jong-Kyu; Boozer, Allen H.; Menard, Jonathan E.; Gerhardt, Stefan P.; Sabbagh, Steve A.

2009-01-01

The imposition of a nonaxisymmetric magnetic perturbation on a rotating tokamak plasma requires energy and toroidal torque. Fundamental electrodynamics implies that the torque is essentially limited and must be consistent with the external response of a plasma equilibrium (rvec f) = (rvec j) x (rvec B). Here magnetic measurements on National Spherical Torus eXperiment (NSTX) device are used to derive the energy and the torque, and these empirical evaluations are compared with theoretical calculations based on perturbed scalar pressure equilibria (rvec f) = (rvec (del))p coupled with the theory of nonambipolar transport. The measurement and the theory are consistent within acceptable uncertainties, but can be largely inconsistent when the torque is comparable to the energy. This is expected since the currents associated with the torque are ignored in scalar pressure equilibria, but these currents tend to shield the perturbation.

Comparison of Stretch Reflex Torques in Ankle Dorsiflexors and Plantarflexors

National Research Council Canada - National Science Library

Tung, J

2001-01-01

...) ankle muscles, Pulse, step, and a combination of random perturbation and step inputs were used to identify the reflex and intrinsic contributions to the measured torque, TA reflex torques were very...

Planetary Torque in 3D Isentropic Disks

Energy Technology Data Exchange (ETDEWEB)

Fung, Jeffrey [Department of Astronomy, University of California at Berkeley, Campbell Hall, Berkeley, CA 94720-3411 (United States); Masset, Frédéric; Velasco, David [Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México, Av. Universidad s/n, 62210 Cuernavaca, Mor. (Mexico); Lega, Elena, E-mail: jeffrey.fung@berkeley.edu [Université de la Côte d’Azur, Observatoire de la Côte d’Azur, CNRS, Laboratoire Lagrange UMR 7293, Nice (France)

2017-03-01

Planetary migration is inherently a three-dimensional (3D) problem, because Earth-size planetary cores are deeply embedded in protoplanetary disks. Simulations of these 3D disks remain challenging due to the steep resolution requirements. Using two different hydrodynamics codes, FARGO3D and PEnGUIn, we simulate disk–planet interaction for a one to five Earth-mass planet embedded in an isentropic disk. We measure the torque on the planet and ensure that the measurements are converged both in resolution and between the two codes. We find that the torque is independent of the smoothing length of the planet’s potential ( r {sub s}), and that it has a weak dependence on the adiabatic index of the gaseous disk ( γ ). The torque values correspond to an inward migration rate qualitatively similar to previous linear calculations. We perform additional simulations with explicit radiative transfer using FARGOCA, and again find agreement between 3D simulations and existing torque formulae. We also present the flow pattern around the planets that show active flow is present within the planet’s Hill sphere, and meridional vortices are shed downstream. The vertical flow speed near the planet is faster for a smaller r {sub s} or γ , up to supersonic speeds for the smallest r {sub s} and γ in our study.

Manual Torque Data Study

Energy Technology Data Exchange (ETDEWEB)

Mundt, Mark Osroe [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Martinez, Matthew Ronald [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Varela, Jeanette Judith [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Anderson-Cook, Christine Michaela [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Gilmore, Walter E. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Williams, Allie [Pantex Plant (PTX), Amarillo, TX (United States)

2018-01-11

At the Pantex Plant in Amarillo, TX, Production Technicians (PTs) build and disassemble nuclear weapon systems. The weapons are held in an integrated work stand for stability and to increase the safety environment for the workers and for the materials being processed. There are many occasions in which a knob must be turned to tighten an assembly part. This can help to secure or manipulate pieces of the system. As there are so many knobs to turn, the instructions given to the PTs are to twist the knob to a hand-tight setting, without the aid of a torque wrench. There are inherent risks in this procedure as the knobs can be tightened too loosely such that the apparatus falls apart or too tightly such that the force can crush or pinch components in the system that contain energetic materials. We want to study these operations at Pantex. Our goal is to collect torque data to assess the safety and reliability of humantooling interfaces.

Effects of cavitation on performance of automotive torque converter

Directory of Open Access Journals (Sweden)

Jaewon Ju

2016-06-01

Full Text Available Cavitation is a phenomenon whereby vapor bubbles of a flowing liquid are formed in a local region where the pressure of the liquid is below its vapor pressure. It is well known that cavitation in torque converters occurs frequently when a car with an automatic transmission makes an abrupt start. Cavitation is closely related to a performance drop and noise generation at a specific operating condition in a car and a torque converter itself. This study addressed the relation between cavitation and performance in an automotive torque converter in a quantitative and qualitative manner using numerical simulations. The cavitation was calculated at various operating conditions using a commercial flow solver with the homogeneous cavitation model, and the torque converter performance was compared with the experimental data. Numerical results well match to the data and indicate that the cavitation causes significant performance drop, as the pump speed increases or both speed ratio and reference pressure decrease.

Torque characteristics of double-stator permanent magnet synchronous machines

Directory of Open Access Journals (Sweden)

Awah Chukwuemeka Chijioke

2017-12-01

Full Text Available The torque profile of a double-stator permanent magnet (PM synchronous machine of 90 mm stator diameter having different rotor pole numbers as well as dual excitation is investigated in this paper. The analysis includes a comparative study of the machine’s torque and power-speed curves, static torque and inductance characteristics, losses and unbalanced magnetic force. The most promising flux-weakening potential is revealed in 13- and 7-rotor pole machines. Moreover, the machines having different rotor/stator (Nr/Ns pole combinations of the form Nr = Ns ± 1 have balanced and symmetric static torque waveforms variation with the rotor position in contrast to the machines having Nr = Ns ± 2. Further, the inductance results of the analyzed machines reveal that the machines with odd rotor pole numbers have better fault-tolerant capability than their even rotor pole equivalents. A prototype of the developed double-stator machine having a 13-pole rotor is manufactured and tested for verification.

Stabilization of Rigid Body Dynamics by Internal and External Torques

National Research Council Canada - National Science Library

Bloch, A. M; Krishnaprasad, P. S; Marsden, J. E; Sanchez de Alvarez, G

1990-01-01

...] with quadratic feedback torques for internal rotors. We show that with such torques, the equations for the rigid body with momentum wheels are Hamiltonian with respect to a Lie-Poisson bracket structure. Further...

Torque Measurement of 3-DOF Haptic Master Operated by Controllable Electrorheological Fluid

Directory of Open Access Journals (Sweden)

Oh Jong-Seok

2015-02-01

Full Text Available This work presents a torque measurement method of 3-degree-of-freedom (3-DOF haptic master featuring controllable electrorheological (ER fluid. In order to reflect the sense of an organ for a surgeon, the ER haptic master which can generate the repulsive torque of an organ is utilized as a remote controller for a surgery robot. Since accurate representation of organ feeling is essential for the success of the robot-assisted surgery, it is indispensable to develop a proper torque measurement method of 3-DOF ER haptic master. After describing the structural configuration of the haptic master, the torque models of ER spherical joint are mathematically derived based on the Bingham model of ER fluid. A new type of haptic device which has pitching, rolling, and yawing motions is then designed and manufactured using a spherical joint mechanism. Subsequently, the field-dependent parameters of the Bingham model are identified and generating repulsive torque according to applied electric field is measured. In addition, in order to verify the effectiveness of the proposed torque model, a comparative work between simulated and measured torques is undertaken.

Uma visão geral da gramática funcional

Directory of Open Access Journals (Sweden)

Maria Helena de Moura Neves

2001-02-01

Full Text Available

O trabalho apresenta uma visão geral do que vem sendo chamado funcionalismo em lingüística. Contrapõem-se os modelos formalista e funcionalista e examinam-se, em especial, as propostas de gramática funcional de C. S. Dik e de M. A. K. Halliday.

RFID Torque Sensing Tag System for Fasteners

Science.gov (United States)

Fink, Patrick W. (Inventor); Lin, Gregory Y. (Inventor); Ngo, Phong H. (Inventor); Kennedy, Timothy F. (Inventor)

2016-01-01

The present invention provides an RFID-based torque sensor that can be used to quickly monitor off the shelf fasteners including fasteners that are used in expensive satellites or other uses where fastener failure can be very costly. In one embodiment, an antenna, RFID ring and spring comprise a sensor tag that can be interrogated with an interrogation signal produced by an interrogator device. When sufficient torque is applied to the fastener, an RFID circuit is connected, and produces a radio frequency (RF) signal that can be read by the interrogator. In one embodiment, the RFID circuit does not transmit when the spring member is not compressed, thereby indicating insufficient tensioning of the fastener. The present invention offers the ability to remotely, quickly, and inexpensively verify that any number of fasteners are torqued properly upon initial installation. Where applicable, the present invention allows low cost monitoring over the life of the fastener.

Compensation of an attitude disturbance torque caused by magnetic substances in LEO satellites

Science.gov (United States)

Inamori, Takaya; Wang, Jihe; Saisutjarit, Phongsatorn; Ohsaki, Hiroyuki

This research considers an attitude disturbance torque caused by ferromagnetic substances in a LEO satellite. In most LEO satellite missions, a gravity gradient torque, solar pressure torque, aerodynamic torque, and magnetic dipole moment torque are considered for their attitude control systems, however, the effect of the ferromagnetic substances causing a disturbance torque in the geomagnetic field is not considered in previous satellite missions. The ferromagnetic substances such as iron cores of MTQs and a magnetic hysteresis damper for a passive attitude control system are used in various small satellites. These substances cause a disturbance torque which is almost the same magnitude of the dipole magnetic disturbance and the dominant disturbance in the worst cases. This research proposes a method to estimate and compensate for the effect of the ferromagnetic substances using an extended Kalman filter. From simulation results, the research concludes that the proposed method is useful and attractive for precise attitude control for LEO satellite missions.

DESENVOLVIMENTO DE SISTEMA DE INDICADORES PARA BENCHMARKING NA CONSTRUÇÃO: USO PARA COMPARTILHAMENTO DE CONHECIMENTO VISANDO À MELHORIA DE DESEMPENHO

Directory of Open Access Journals (Sweden)

Dayana Bastos Costa

2007-11-01

Full Text Available Nos últimos anos, as empresas de construção vêm investindo em sistemas de medição de desempenho, especialmente para comparação de desempenho. Neste contexto, em 2003 foi iniciado um projeto cujo objetivo foi desenvolver e implementar um Sistema de Indicadores para Benchmarking na Construção, utilizando a Tecnologia da Informação. Para tanto foram desenvolvidos dois mecanismos, o Clube de Benchmarking, como uma rede para compartilhamento de práticas e experiências entre as empresas de construção e o Sistema de Indicadores On-line, que permite o ingresso de dados dos indicadores diretamente pelas empresas e o acesso aos resultados para a comparação de desempenho. Este artigo tem como objetivo apresentar e discutir o processo de desenvolvimento, implementação e uso destes dois mecanismos como facilitadores para o compartilhamento de conhecimento e comparação de desempenho visando à melhoria de desempenho das empresas de construção. O estudo foi realizado utilizando a estratégia de pesquisa-ação. Vinte empresas de construção da Região Metropolitana de Porto Alegre participaram do projeto, ao longo de um período de três anos. Os resultados obtidos são apresentados a partir da descrição das principais características tanto Clube quanto do sistema on-line desenvolvidos. Como conclusão, identificou-se por um lado que ambos os mecanismos facilitaram o compartilhamento de conhecimentos e comparação de desempenho entre as empresas de construção, e permitiram que as mesmas alcançassem melhorias de desempenho. Entretanto, as melhorias de desempenho alcançadas pelas empresas são dependentes: (a do nível de maturidade das empresas, que se refere o quanto os processos organizacionais e gerenciais destas empresas estão desenvolvidos; e (b a capacidade de absorção, que significa a habilidade das empresas de reconhecer o valor do conhecimento disponibilizado externamente, de modo a adquirir, entender, disseminar

ANÁLISE DO DESEMPENHO ACÚSTICO DE FACHADAS VENTILADAS DE PORCELANATO À LUZ DA NORMA DE DESEMPENHO: ESTUDO DE CASO EM UM EDIFÍCIO HABITACIONAL EM BRASÍLIA-DF

Directory of Open Access Journals (Sweden)

Vamberto Machado dos Santos Filho

2017-05-01

Full Text Available RESUMO: A entrada de novos sistemas construtivos no mercado brasileiro tem sido acompanhada de diversos questionamentos sobre o seu desempenho. Entre estes novos sistemas estão as fachadas ventiladas, que surgem com o apelo de um sistema com o potencial de melhorar os aspectos de habitabilidade da edificação. Neste trabalho foi realizado um estudo de desempenho acústico de fachadas ventiladas com porcelanato (FVPo, comparativamente às fachadas de porcelanato aderido (FPoA. Para isto, foi utilizado um projeto de uma edificação habitacional modelo (EHM para reproduzir as edificações típicas do Plano Piloto de Brasília-DF. Para os cálculos foi utilizado o software Insul e os critérios da norma de desempenho, a NBR 15575 (ABNT, 2013. Para cada critério da norma, os dois sistemas foram comparados e analisados com base nos resultados obtidos na simulação. Os dois sistemas apresentaram o mesmo índice de isolamento sonoro, com um nível mínimo de desempenho. Foi possível verificar a importância da esquadria no isolamento do sistema de fachada, pois ao aumentar a área da esquadria, o índice de isolamento diminui. Este trabalho traz como principal contribuição a avaliação de desempenho acústico para sistemas inovadores no setor brasileiro de edificações. ABSTRACT: The insertion of new construction systems in the Brazilian market has been accompanied by many questions about its performance. Among these new systems there is the ventilated façades, which has the potential to improve aspects of building habitability. In this paper, the acoustic performance of a porcelain ventilated façade (FVPo was compared to a joined porcelain façade (FPoA. A residential building model design (EHM was used to reproduce the typical buildings of Brasilia-DF. The software Insul and performance standard criteria, in the NBR 15575 (ABNT, 2013, was used to calculate the values. For each criteria of the performance standard, the two systems were

Mode coupling in spin torque oscillators

International Nuclear Information System (INIS)

Zhang, Steven S.-L.; Zhou, Yan; Li, Dong; Heinonen, Olle

2016-01-01

A number of recent experimental works have shown that the dynamics of a single spin torque oscillator can exhibit complex behavior that stems from interactions between two or more modes of the oscillator, such as observed mode-hopping or mode coexistence. There has been some initial work indicating how the theory for a single-mode (macro-spin) spin torque oscillator should be generalized to include several modes and the interactions between them. In the present work, we rigorously derive such a theory starting with the Landau–Lifshitz–Gilbert equation for magnetization dynamics by expanding up to third-order terms in deviation from equilibrium. Our results show how a linear mode coupling, which is necessary for observed mode-hopping to occur, arises through coupling to a magnon bath. The acquired temperature dependence of this coupling implies that the manifold of orbits and fixed points may shift with temperature. - Highlights: • Deriving equations for coupled modes in spin torque oscillators. • Including Hamiltonian formalism and elimination of three–magnon processes. • Thermal bath of magnons central to mode coupling. • Numerical examples of circular and elliptical devices.

Mode coupling in spin torque oscillators

Energy Technology Data Exchange (ETDEWEB)

Zhang, Steven S.-L., E-mail: ZhangShule@missouri.edu [Department of Physics and Astronomy, University of Missouri, Columbia, MO 65211 (United States); Zhou, Yan, E-mail: yanzhou@hku.hk [Department of Physics, The University of Hong Kong, Hong Kong (China); Center of Theoretical and Computational Physics, University of Hong Kong, Hong Kong (China); Li, Dong, E-mail: geodesic.ld@gmail.com [Department of Physics, Centre for Nonlinear Studies, and Beijing-Hong Kong-Singapore Joint Centre for Nonlinear and Complex Systems, Hong Kong Baptist University, Kowloon Tong, Hong Kong (China); Heinonen, Olle, E-mail: heinonen@anl.gov [Material Science Division, Argonne National Laboratory, Lemont, IL 60439 (United States); Northwestern-Argonne Institute of Science and Technology, 2145 Sheridan Road, Evanston, IL 60208 (United States); Computation Institute, The Unversity of Chicago, 5735 S Ellis Avenue, Chicago, IL 60637 (United States)

2016-09-15

A number of recent experimental works have shown that the dynamics of a single spin torque oscillator can exhibit complex behavior that stems from interactions between two or more modes of the oscillator, such as observed mode-hopping or mode coexistence. There has been some initial work indicating how the theory for a single-mode (macro-spin) spin torque oscillator should be generalized to include several modes and the interactions between them. In the present work, we rigorously derive such a theory starting with the Landau–Lifshitz–Gilbert equation for magnetization dynamics by expanding up to third-order terms in deviation from equilibrium. Our results show how a linear mode coupling, which is necessary for observed mode-hopping to occur, arises through coupling to a magnon bath. The acquired temperature dependence of this coupling implies that the manifold of orbits and fixed points may shift with temperature. - Highlights: • Deriving equations for coupled modes in spin torque oscillators. • Including Hamiltonian formalism and elimination of three–magnon processes. • Thermal bath of magnons central to mode coupling. • Numerical examples of circular and elliptical devices.

Comparação dos erros ortográficos de alunos com desempenho inferior em escrita e alunos com desempenho médio nesta habilidade A comparison study of the orthographics mistakes of students with inferior and students with average writing performance

Directory of Open Access Journals (Sweden)

Patrícia Aparecida Zuanetti

2008-01-01

Full Text Available OBJETIVO: O objetivo deste estudo foi comparar se crianças com baixo desempenho em escrita cometem mais erros ortográficos que crianças da mesma série com desempenho satisfatório nesta tarefa, e quais os tipos de erros ortográficos mais freqüentes. MÉTODOS: Participaram deste estudo 24 crianças da 2ª série do ensino fundamental de uma escola pública, avaliadas individualmente. O teste aplicado foi o subteste de escrita do Teste de Desempenho Escolar, composto por 34 palavras que são ditadas aos alunos. RESULTADOS: Os alunos com desempenho inferior em escrita cometeram significativamente mais erros ortográficos que o grupo com desempenho satisfatório. Os erros que tiveram diferença estatisticamente significativa entre os dois grupos foram erros do tipo hipercorreção, dificuldade com marcadores de nasalização, relação fonografêmica irregular, omissões de sílabas e erros por troca de letras. Também houve correlação fortemente negativa entre erros ortográficos e desempenho em escrita. CONCLUSÕES: Quanto melhor o desempenho em escrita, menos erros ortográficos possui a elaboração gráfica do aluno. Os erros mais freqüentes no grupo com desempenho baixo, que os difere do outro grupo, dizem respeito aos erros de relação fonografêmica irregular, omissões de sílabas, dificuldade no uso de marcadores de nasalização, hipercorreção e erros por troca de letras. Com o avanço da capacidade de aprendizagem da criança, o desempenho ortográfico tende a melhorar.PURPOSE: The aim of this study was to verify whether children with poor writing performances make more orthographic mistakes than children of the same school grade with average performances, and what are the most frequent types of orthographic mistakes. METHODS: Twenty-four second grade children from a public school were individually analyzed in this study. The test used was the writing subtest of the School Performance Test, which is composed by 34 words that

PARTICULARES QUE EJERCEN FUNCIONES ADMINISTRATIVAS: EL CASO DE LOS TRIBUNALES DE ÉTICA PROFESIONAL

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David Suárez Tamayo

2012-05-01

Full Text Available Los tribunales de ética profesional son una de las tantas manifestaciones de la llamada descentralización por colaboración, mediante la cual, los particulares ejercen funciones administrativas. Dicha participación de los particulares en la gestión pública encuentra su fundamento en los artículos 2, 26, 123 y 210de la Constitución Política de Colombia de 1991. En la investigación realizadase encontró que en Colombia existen 29 tribunales, colegios o consejos de profesionales que tienen como una de sus funciones investigar y sancionar las conductas contra la ética profesional. En el trabajo se intenta abordar la manera como están integrados, los principios y procedimientos que siguen, el tipo de faltas que investigan, las sanciones que imponen, los términos de caducidad y prescripción, la garantía del debido proceso y la existencia o no de la segunda instancia. Finalmente se hace un inventario de los efectos e implicaciones que se siguen del hecho de ser particulares en ejercicio de funciones administrativas

Two-Finger Tightness: What Is It? Measuring Torque and Reproducibility in a Simulated Model.

Science.gov (United States)

Acker, William B; Tai, Bruce L; Belmont, Barry; Shih, Albert J; Irwin, Todd A; Holmes, James R

2016-05-01

Residents in training are often directed to insert screws using "two-finger tightness" to impart adequate torque but minimize the chance of a screw stripping in bone. This study seeks to quantify and describe two-finger tightness and to assess the variability of its application by residents in training. Cortical bone was simulated using a polyurethane foam block (30-pcf density) that was prepared with predrilled holes for tightening 3.5 × 14-mm long cortical screws and mounted to a custom-built apparatus on a load cell to capture torque data. Thirty-three residents in training, ranging from the first through fifth years of residency, along with 8 staff members, were directed to tighten 6 screws to two-finger tightness in the test block, and peak torque values were recorded. The participants were blinded to their torque values. Stripping torque (2.73 ± 0.56 N·m) was determined from 36 trials and served as a threshold for failed screw placement. The average torques varied substantially with regard to absolute torque values, thus poorly defining two-finger tightness. Junior residents less consistently reproduced torque compared with other groups (0.29 and 0.32, respectively). These data quantify absolute values of two-finger tightness but demonstrate considerable variability in absolute torque values, percentage of stripping torque, and ability to consistently reproduce given torque levels. Increased years in training are weakly correlated with reproducibility, but experience does not seem to affect absolute torque levels. These results question the usefulness of two-finger tightness as a teaching tool and highlight the need for improvement in resident motor skill training and development within a teaching curriculum. Torque measuring devices may be a useful simulation tools for this purpose.

As emoções como fator de modelação no desempenho desportivo

OpenAIRE

Santos, Sebastião Ferreira dos

2017-01-01

Tese de Doutoramento em Ciências do Desporto, Especialização em Psicologia do Desporto A investigação científica do século XXI debruçar-se-á sobre o cérebro, como a grande viagem das descobertas. As emoções são a génese do ser humano e são encarnadas como fatores de influência no desempenho desportivo. Os relatos dos agentes desportivos revelam-nos, que muitas vezes, as emoções são o catalisador de rendimentos medíocres, de falhas que geram pesares, a desempenhos fabulosos que ...

Spin-orbit torque in two-dimensional antiferromagnetic topological insulators

KAUST Repository

Ghosh, Sumit; Manchon, Aurelien

2017-01-01

We investigate spin transport in two-dimensional ferromagnetic (FTI) and antiferromagnetic (AFTI) topological insulators. In the presence of an in-plane magnetization AFTI supports zero energy modes, which enables topologically protected edge conduction at low energy. We address the nature of current-driven spin torque in these structures and study the impact of spin-independent disorder. Interestingly, upon strong disorder the spin torque develops an antidamping component (i.e., even upon magnetization reversal) along the edges, which could enable current-driven manipulation of the antiferromagnetic order parameter. This antidamping torque decreases when increasing the system size and when the system enters the trivial insulator regime.

Spin-orbit torque in two-dimensional antiferromagnetic topological insulators

KAUST Repository

Ghosh, Sumit

2017-01-24

We investigate spin transport in two-dimensional ferromagnetic (FTI) and antiferromagnetic (AFTI) topological insulators. In the presence of an in-plane magnetization AFTI supports zero energy modes, which enables topologically protected edge conduction at low energy. We address the nature of current-driven spin torque in these structures and study the impact of spin-independent disorder. Interestingly, upon strong disorder the spin torque develops an antidamping component (i.e., even upon magnetization reversal) along the edges, which could enable current-driven manipulation of the antiferromagnetic order parameter. This antidamping torque decreases when increasing the system size and when the system enters the trivial insulator regime.

Condições do letramento funcional em saúde de um grupo de idosos diabéticos

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Maria Izabel Penha de Oliveira Santos

2016-02-01

Full Text Available RESUMO Objetivo: foi avaliar as condições de letramento funcional em saúde de um grupo de idosos diabéticos. Método: estudo seccional e descritivo, com idosos diabéticos assistidos no SUS (N = 114. Avaliaram-se os condicionantes sociais e da saúde, bem como de letramento funcional em saúde pelo teste S-TOFHLA(versão-breve; descreveram-se as proporções simples, média, desvio-padrão e teste do Qui-quadrado de Pearson pelo software SPSS (20.0 com valor α = 5%. Resultados: a média da idade foi 67,4 anos, 74,0% dos idosos eram mulheres, possuíam até 4 anos de escolaridade; 29,8% tinham a doença de longa data, 64,0% relataram ter hipertensão arterial, 47,4% eram ou foram fumantes, 73,7% apresentaram baixo letramento funcional em saúde, que se mostrou associado com a escolaridade p = 0,001. Conclusões: o baixo letramento funcional em saúde pode ser condicionante do autocuidado e pode ser influenciado pela baixa escolaridade, pois implica em ter habilidades para compreender e tomar decisões voltadas à autogestão da saúde.

Spin transfer torque with spin diffusion in magnetic tunnel junctions

KAUST Repository

Manchon, Aurelien

2012-08-09

Spin transport in magnetic tunnel junctions in the presence of spin diffusion is considered theoretically. Combining ballistic tunneling across the barrier and diffusive transport in the electrodes, we solve the spin dynamics equation in the metallic layers. We show that spin diffusion mixes the transverse spin current components and dramatically modifies the bias dependence of the effective spin transfer torque. This leads to a significant linear bias dependence of the out-of-plane torque, as well as a nonconventional thickness dependence of both spin torque components.

Effect of Different Torque Settings on Crack Formation in Root Dentin.

Science.gov (United States)

Dane, Asım; Capar, Ismail Davut; Arslan, Hakan; Akçay, Merve; Uysal, Banu

2016-02-01

The aim of the present study was to observe the incidence of cracks in root canal dentin using the ProTaper Universal system (Dentsply Maillefer, Ballaigues, Switzerland) at low- and high-torque settings. Sixty-nine mandibular premolar teeth that had been extracted for different reasons were selected. The teeth were divided into 3 groups: an unprepared control group, a low-torque settings group (SX = 3, S1 = 2, S2 = 1, F1 = 1.5, F2 = 2, F3 = 2, F4 = 2 N/cm), and a high-torque settings group (SX = 4, S1 = 4, S2 = 1.5, F1 = 2, F2 = 3, F3 = 3, F4 = 3 N/cm). After a root canal procedure, all the teeth were horizontally sectioned at 2, 4, 6, and 8 mm from the apex. Then, under a stereomicroscope, all the slices were examined to determine the presence of cracks. A chi-square test was used for data analysis. The significance level was set at P = .05. There were no cracks in the unprepared control group. Vertical root fractures were not observed in any of the groups. There were significantly fewer cracks (17.4% of the sections) in the low-torque group than in the high-torque group (29.4% of the sections) (P torque than at low-torque settings. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Harmonic Analysis on Torque Ripple of Brushless DC Motor Based on Advanced Commutation Control

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Yanpeng Ji

2018-01-01

Full Text Available This paper investigates the relationship between current, back electromotive force (back-EMF, and torque for permanent-magnet brushless DC (PM BLDC motors under advanced commutation control from the perspective of harmonics. Considering that the phase current is the influencing factor of both torque and torque ripple, this paper firstly analyzes the effects of advanced commutation on phase current and current harmonics. And then, based on the harmonics of the phase current and back-EMF, the torque harmonic expressions are deduced. The expressions reveal the relationship of harmonic order between the torque, phase current, and back-EMF and highlight the different contribution of individual torque harmonic to the total torque ripple. Finally, the proposed harmonic analysis method is verified by the experiments with different speed and load conditions.

Age-related reduction of trunk muscle torque and prevalence of trunk sarcopenia in community-dwelling elderly: Validity of a portable trunk muscle torque measurement instrument and its application to a large sample cohort study.

Science.gov (United States)

Sasaki, Eiji; Sasaki, Shizuka; Chiba, Daisuke; Yamamoto, Yuji; Nawata, Atsushi; Tsuda, Eiichi; Nakaji, Shigeyuki; Ishibashi, Yasuyuki

2018-01-01

Trunk muscle weakness and imbalance are risk factors for postural instability, low back pain, and poor postoperative outcomes. The association between trunk muscle strength and aging is poorly understood, and establishing normal reference values is difficult. We aimed to establish the validity of a novel portable trunk muscle torque measurement instrument (PTMI). We then estimated reference data for healthy young adults and elucidated age-related weakness in trunk muscle strength. Twenty-four university students were enrolled to validate values for PTMI, and 816 volunteers from the general population who were recruited to the Iwaki Health Promotion Project were included to estimate reference data for trunk muscle strength. Trunk flexion and extension torque were measured with PTMI and KinCom, and interclass correlation coefficients (ICC) were estimated to evaluate the reliability of PTMI values. Furthermore, from the young adult reference, the age-related reduction in trunk muscle torque and the prevalence of sarcopenia among age-sex groups were estimated. The ICC in flexion and extension torque were 0.807 (psarcopenia increased with age, and the prevalence due to flexion torque was double that of extension torque. Flexion torque decreased significantly after 60 years of age, and extension torque decreased after 70 years of age. In males over age 80, trunk muscle torque decreased to 49.1% in flexion and 63.5% in extension. In females over age 80, trunk muscle torque decreased to 60.7% in flexion and 68.4% in extension. The validity of PTMI was confirmed by correlation with KinCom. PTMI produced reference data for healthy young adults, and demonstrated age-related reduction in trunk muscle torque. Trunk sarcopenia progressed with aging, and the loss of flexion torque began earlier than extension torque. At age 80, trunk muscle torque had decreased 60% compared with healthy young adults.

Funciones sociales del consumo: un caso extremo

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JOSÉ CASTILLO CASTILLO

1994-01-01

Full Text Available El consumo religioso de reliquías de santos durante la edad media cumple semejantes funciones sociales para su época que el consumo economico de objetos para la nuestra: El de reforzar real y simbólicamente las estructuras de prestigio, riqueza y poder de sus respectivas sociedades. El ámbito de la sociología del consumo no se circunscribe a los estrechos límites de las llamadas sociedades de consumo de masas. en el presente caso, el estudio del pasado ilumina procesos sociales propios de nuestros días.

Steady flow torques in a servo motor operated rotary directional control valve

International Nuclear Information System (INIS)

Wang, He; Gong, Guofang; Zhou, Hongbin; Wang, Wei

2016-01-01

Highlights: • A novel servo motor operated rotary directional control valve is proposed. • Steady flow torque is a crucial issue that affects rotary valve performance. • Steady flow torque is analyzed on the aspects of theory, simulation and experiment. • Change law of the steady flow torque with spool rotation angle is explored. • Effect of pressure drop and flow rate on the steady flow torque is studied. - Abstract: In this paper, a servo motor operated rotary directional control valve is proposed, and a systematic analysis of steady flow torques in this valve is provided by theoretical calculation, CFD simulation and experimental test. In the analysis, spool rotation angle corresponding to the maximum orifice opening is tagged as 0°. Over a complete change cycle of the orifice, the range of spool rotation angle is symmetric about 0°. The results show that the direction of steady flow torques in this valve is always the direction of orifice closing. The steady flow torques serve as resistances to the spool rotation when the orifice opening increases, while impetuses to the spool rotation when the orifice opening decreases. At a certain pressure drop or flow rate, steady flow torques are approximately equal and opposite when at spool rotation angles which are symmetric about 0°. When the spool rotates from 0°, at a certain pressure drop, their values increase first then decrease with the spool rotation and reach their maximum values at an angle corresponding to about 1/2 of the maximum orifice opening, and at a certain flow rate, their values increase with the spool rotation. The steady flow torques in this valve are the sums of those in the meter-in and meter-out valve chambers. At a certain spool rotation angle, steady flow torques in the meter-in and meter-out valve chambers are approximately proportional to the pressure drop and the second power of the flow rate through the orifice. Theoretical calculation and CFD simulation can be validated by

THREE-DIMENSIONAL DISK-PLANET TORQUES IN A LOCALLY ISOTHERMAL DISK

International Nuclear Information System (INIS)

D'Angelo, Gennaro; Lubow, Stephen H.

2010-01-01

We determine an expression for the Type I planet migration torque involving a locally isothermal disk, with moderate turbulent viscosity (5 x 10 -4 ∼< α ∼< 0.05), based on three-dimensional nonlinear hydrodynamical simulations. The radial gradients (in a dimensionless logarithmic form) of density and temperature are assumed to be constant near the planet. We find that the torque is roughly equally sensitive to the surface density and temperature radial gradients. Both gradients contribute to inward migration when they are negative. Our results indicate that two-dimensional calculations with a smoothed planet potential, used to account for the effects of the third dimension, do not accurately determine the effects of density and temperature gradients on the three-dimensional torque. The results suggest that substantially slowing or stopping planet migration by means of changes in disk opacity or shadowing is difficult and appears unlikely for a disk that is locally isothermal. The scalings of the torque and torque density with planet mass and gas sound speed follow the expectations of linear theory. We also determine an improved formula for the torque density distribution that can be used in one-dimensional long-term evolution studies of planets embedded in locally isothermal disks. This formula can be also applied in the presence of mildly varying radial gradients and of planets that open gaps. We illustrate its use in the case of migrating super-Earths and determine some conditions sufficient for survival.

Universal adaptive torque control for PM motors for field-weakening region operation

Science.gov (United States)

Royak, Semyon [Beachwood, OH; Harbaugh, Mark M [Richfield, OH; Breitzmann, Robert J [South Russel, OH; Nondahl, Thomas A [Wauwatosa, WI; Schmidt, Peter B [Franklin, WI; Liu, Jingbo [Milwaukee, WI

2011-03-29

The invention includes a motor controller and method for controlling a permanent magnet motor. In accordance with one aspect of the present technique, a permanent magnet motor is controlled by, among other things, receiving a torque command, determining a normalized torque command by normalizing the torque command to a characteristic current of the motor, determining a normalized maximum available voltage, determining an inductance ratio of the motor, and determining a direct-axis current based upon the normalized torque command, the normalized maximum available voltage, and the inductance ratio of the motor.

On the monoaxial stabilization of a rigid body under vanishing restoring torque

Science.gov (United States)

Aleksandrov, A. Yu.; Aleksandrova, E. B.; Tikhonov, A. A.

2018-05-01

The problem of monoaxial stabilization of a rigid body is studied. It is assumed that a linear time-invariant dissipative torque and a time-varying restoring torque vanishing as time increases act on the body. Both the case of linear restoring torque and that of essentially nonlinear one are considered. With the aid of the decomposition method, conditions are obtained under which we can guarantee the asymptotic stability of an equilibrium position of the body despite the vanishing of the restoring torque. A numerical simulation is provided to demonstrate the effectiveness of our theoretical results.

Correlação entre flexibilidade das articulações glenoumerais e coxofemorais e o desempenho funcional de idosas fisicamente ativas Association between flexibility of the glenohumeral and hip joints and functional performance in active elderly women

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AAR Geraldes

2008-08-01

Full Text Available OBJETIVO: Investigar a relação entre a flexibilidade da flexão e extensão das articulações glenoumerais (GU e coxofemorais (CF e o desempenho funcional (DF de idosas funcionalmente independentes e fisicamente ativas. MÉTODOS: Determinou-se em 22 voluntárias (idade=70±6 anos seis conjuntos de amplitudes de movimentos por goniometria ativo-assistida (ADM na flexão e extensão das GU e CF. O DF foi determinado pelos testes: velocidade de caminhada habitual (VCH e máxima (VCM; levantar e sentar em cadeira (LSC; Timed up and Go Test (TUGT; vestir blusa (VBL; subir degraus (SE; levantar do decúbito dorsal (LDD; pegar moeda no solo (PMS; teste de caminhada de seis minutos (TC6M. As associações entre as variáveis ADM e o DF foram testadas por técnicas de correlação simples e múltipla. RESULTADOS: Houve correlações significantes (pOBJECTIVE: To investigate the relationship between flexibility of flexion and extension of the glenohumeral and coxofemoral joints and functional performance among physically active and functionally independent elderly women. METHODS: Six sets of range of motion (ROM measurements relating to flexion and extension of the glenohumeral and coxofemoral joints were determined in 22 volunteers (age 70±6 years, using assisted-active goniometry. Functional performance was measured using the following tests: normal walking speed (NWS; maximum walking speed (MWS; sit-to-stand test (SST; timed up and go test (TUGT; putting on a blouse (PBL; going up stairs (GUS; rising from dorsal decubitus (RDD; picking up a coin from the floor (PCF; and 6-minute walk test (6WT. The relationships between the ROM variables and functional performance were tested using simple and multiple regression techniques. RESULTS: There were significant correlations (p<0.05 between coxofemoral ROM and the SST (r=0.42 and r=0.45, GUS (r=0.52 and r=0.53 and 6WT (r=0.58 and r=0.59 (right and left sides, respectively. The multiple regression ratified

Avaliação do desempenho ambiental do processo produtivo de uma indústria madeireira

OpenAIRE

Debora Luciane Giacomet

2008-01-01

Esta dissertação aborda a avaliação do desempenho ambiental do processo produtivo em uma indústria madeireira. O trabalho está baseado na revisão de literatura sobre o tema, no mapeamento do processo produtivo e na aplicação das ferramentas de verificação de desempenho ambiental de Echeveste et al. (2002) e de Lean Environment Toolkit. A revisão de literatura investigou aspectos como sustentabilidade, sistemas de gestão ambiental, normas e certificações, ecodesign, subprodutos e resíduos e cl...

Spin-orbit torques in locally and globally noncentrosymmetric crystals: Antiferromagnets and ferromagnets

KAUST Repository

Železný , J.; Gao, H.; Manchon, Aurelien; Freimuth, Frank; Mokrousov, Yuriy; Zemen, J.; Mašek, J.; Sinova, Jairo; Jungwirth, T.

2017-01-01

One of the main obstacles that prevents practical applications of antiferromagnets is the difficulty of manipulating the magnetic order parameter. Recently, following the theoretical prediction [J. Železný, Phys. Rev. Lett. 113, 157201 (2014)]PRLTAO0031-900710.1103/PhysRevLett.113.157201, the electrical switching of magnetic moments in an antiferromagnet was demonstrated [P. Wadley, Science 351, 587 (2016)]SCIEAS0036-807510.1126/science.aab1031. The switching is due to the so-called spin-orbit torque, which has been extensively studied in ferromagnets. In this phenomena a nonequilibrium spin-polarization exchange coupled to the ordered local moments is induced by current, hence exerting a torque on the order parameter. Here we give a general systematic analysis of the symmetry of the spin-orbit torque in locally and globally noncentrosymmetric crystals. We study when the symmetry allows for a nonzero torque, when is the torque effective, and its dependence on the applied current direction and orientation of magnetic moments. For comparison, we consider both antiferromagnetic and ferromagnetic orders. In two representative model crystals we perform microscopic calculations of the spin-orbit torque to illustrate its symmetry properties and to highlight conditions under which the spin-orbit torque can be efficient for manipulating antiferromagnetic moments.

Spin-orbit torques in locally and globally noncentrosymmetric crystals: Antiferromagnets and ferromagnets

KAUST Repository

Železný, J.

2017-01-10

One of the main obstacles that prevents practical applications of antiferromagnets is the difficulty of manipulating the magnetic order parameter. Recently, following the theoretical prediction [J. Železný, Phys. Rev. Lett. 113, 157201 (2014)]PRLTAO0031-900710.1103/PhysRevLett.113.157201, the electrical switching of magnetic moments in an antiferromagnet was demonstrated [P. Wadley, Science 351, 587 (2016)]SCIEAS0036-807510.1126/science.aab1031. The switching is due to the so-called spin-orbit torque, which has been extensively studied in ferromagnets. In this phenomena a nonequilibrium spin-polarization exchange coupled to the ordered local moments is induced by current, hence exerting a torque on the order parameter. Here we give a general systematic analysis of the symmetry of the spin-orbit torque in locally and globally noncentrosymmetric crystals. We study when the symmetry allows for a nonzero torque, when is the torque effective, and its dependence on the applied current direction and orientation of magnetic moments. For comparison, we consider both antiferromagnetic and ferromagnetic orders. In two representative model crystals we perform microscopic calculations of the spin-orbit torque to illustrate its symmetry properties and to highlight conditions under which the spin-orbit torque can be efficient for manipulating antiferromagnetic moments.

A Terapia por contensão induzida no desempenho ocupacional de crianças com paralisia cerebral / Intervention by contraint- induced movement therapy on the occupational performance of children with cerebral palsy

Directory of Open Access Journals (Sweden)

Cassandra da Silva Fonseca

2018-04-01

Full Text Available A paralisia cerebral (PC constitui um quadro clínico importante que pode acometer crianças, causando déficits de movimento, controle postural, prejuízos sensoriais e cognitivos, com isso, faz-se necessário estimular as habilidades da criança para que alcance um desempenho efetivo em todas as áreas de ocupação. O objetivo deste trabalho foi realizar terapia por contensão induzida que consiste na imobilização do membro superior não afetado com um treino intensivo da extremidade afetada, em crianças com PC hemiplégica. Trata-se de um estudo quase experimental, do tipo antes e depois, não cego e não randomizado. Utilizou-se a Teenager Motor Activity Log- TMAL, a Pediatric Arm Function Test- PAFT e a Inventory of New Motor Activities Program- INMAP para analisar o desempenho funcional dos participantes antes e após o tratamento. A amostra do estudo foi composta por 2 crianças com PC Hemiplégica. A avaliação TMAL identificou melhora na freqüência e qualidade dos movimentos realizados com o membro afetado nas duas intervenções. Da mesma forma a avaliação PAFT demonstrou um aumento na realização de tarefas unilaterais e bilaterais com o membro afetado, sem necessitar de comandos. A INMAP apresentou melhora principalmente nos padrões de alcance, pinça eficiente e preensão. Os resultados demonstram que após a intervenção, houve um aumento significativo no desempenho funcional de atividades motoras das crianças. Neste sentido, acredita-se que intervenções como esta permitem uma reabilitação para aquisição de maior autonomia e independência em atividades cotidianas. AbstractCerebral palsy (CP forms an important clinical picture that may affect children by causing them movement and postural control deficits, sensory and cognitive damages. Therefore, it is necessary to stimulate children’s skills so that they can achieve an effective performance in all occupational areas. The aim of this work is to carry out a

Computations of Torque-Balanced Coaxial Rotor Flows

Science.gov (United States)

Yoon, Seokkwan; Chan, William M.; Pulliam, Thomas H.

2017-01-01

Interactional aerodynamics has been studied for counter-rotating coaxial rotors in hover. The effects of torque balancing on the performance of coaxial-rotor systems have been investigated. The three-dimensional unsteady Navier-Stokes equations are solved on overset grids using high-order accurate schemes, dual-time stepping, and a hybrid turbulence model. Computational results for an experimental model are compared to available data. The results for a coaxial quadcopter vehicle with and without torque balancing are discussed. Understanding interactions in coaxial-rotor flows would help improve the design of next-generation autonomous drones.

Torque Split Strategy for Parallel Hybrid Electric Vehicles with an Integrated Starter Generator

Directory of Open Access Journals (Sweden)

Zhumu Fu

2014-01-01

Full Text Available This paper presents a torque split strategy for parallel hybrid electric vehicles with an integrated starter generator (ISG-PHEV by using fuzzy logic control. By combining the efficiency map and the optimum torque curve of the internal combustion engine (ICE with the state of charge (SOC of the batteries, the torque split strategy is designed, which manages the ICE within its peak efficiency region. Taking the quantified ICE torque, the quantified SOC of the batteries, and the quantified ICE speed as inputs, and regarding the output torque demanded on the ICE as an output, a fuzzy logic controller (FLC with relevant fuzzy rules has been developed to determine the optimal torque distribution among the ICE, the ISG, and the electric motor/generator (EMG effectively. The simulation results reveal that, compared with the conventional torque control strategy which uses rule-based controller (RBC in different driving cycles, the proposed FLC improves the fuel economy of the ISG-PHEV, increases the efficiency of the ICE, and maintains batteries SOC within its operation range more availably.

Shot noise of spin current and spin transfer torque

Science.gov (United States)

Yu, Yunjin; Zhan, Hongxin; Wan, Langhui; Wang, Bin; Wei, Yadong; Sun, Qingfeng; Wang, Jian

2013-04-01

We report the theoretical investigation of the shot noise of the spin current (Sσ) and the spin transfer torque (Sτ) for non-collinear spin polarized transport in a spin-valve device which consists of a normal scattering region connected by two ferromagnetic electrodes (MNM system). Our theory was developed using the non-equilibrium Green’s function method, and general nonlinear Sσ - V and Sτ - V relations were derived as a function of the angle θ between the magnetizations of two leads. We have applied our theory to a quantum dot system with a resonant level coupled with two ferromagnetic electrodes. It was found that, for the MNM system, the auto-correlation of the spin current is enough to characterize the fluctuation of the spin current. For a system with three ferromagnetic layers, however, both auto-correlation and cross-correlation of the spin current are needed to characterize the noise of the spin current. For a quantum dot with a resonant level, the derivative of spin torque with respect to bias voltage is proportional to sinθ when the system is far away from resonance. When the system is near resonance, the spin transfer torque becomes a non-sinusoidal function of θ. The derivative of the noise of the spin transfer torque with respect to the bias voltage Nτ behaves differently when the system is near or far away from resonance. Specifically, the differential shot noise of the spin transfer torque Nτ is a concave function of θ near resonance while it becomes a convex function of θ far away from resonance. For certain bias voltages, the period Nτ(θ) becomes π instead of 2π. For small θ, it was found that the differential shot noise of the spin transfer torque is very sensitive to the bias voltage and the other system parameters.

Current control of PMSM based on maximum torque control reference frame

Science.gov (United States)

Ohnuma, Takumi

2017-07-01

This study presents a new method of current controls of PMSMs (Permanent Magnet Synchronous Motors) based on a maximum torque control reference frame, which is suitable for high-performance controls of the PMSMs. As the issues of environment and energy increase seriously, PMSMs, one of the AC motors, are becoming popular because of their high-efficiency and high-torque density in various applications, such as electric vehicles, trains, industrial machines, and home appliances. To use the PMSMs efficiently, a proper current control of the PMSMs is necessary. In general, a rotational coordinate system synchronizing with the rotor is used for the current control of PMSMs. In the rotating reference frame, the current control is easier because the currents on the rotating reference frame can be expressed as a direct current in the controller. On the other hand, the torque characteristics of PMSMs are non-linear and complex; the PMSMs are efficient and high-density though. Therefore, a complicated control system is required to involve the relation between the torque and the current, even though the rotating reference frame is adopted. The maximum torque control reference frame provides a simpler way to control efficiently the currents taking the torque characteristics of the PMSMs into consideration.

Improvement of Torque Production in Single-Phase Induction Motors

African Journals Online (AJOL)

OLUWASOGO

PID controller. Simulation results show the starting torque of the motor increased by 75% under the developed drive scheme. In addition, torque pulsations reduced from 1.4 Nm peak-peak to 0.14 Nm peak-peak at steady state. It was observed that the accelerating time reduced by 30% compared to the accelerating time ...

Role of external torque in the formation of ion thermal internal transport barriers

Science.gov (United States)

Jhang, Hogun; Kim, S. S.; Diamond, P. H.

2012-04-01

We present an analytic study of the impact of external torque on the formation of ion internal transport barriers (ITBs). A simple analytic relation representing the effect of low external torque on transport bifurcations is derived based on a two field transport model of pressure and toroidal momentum density. It is found that the application of an external torque can either facilitate or hamper bifurcation in heat flux driven plasmas depending on its sign relative to the direction of intrinsic torque. The ratio between radially integrated momentum (i.e., external torque) density to power input is shown to be a key macroscopic control parameter governing the characteristics of bifurcation.

Efectos de un programa de entrenamiento funcional en la musculatura core en mujeres con fibromialgia

OpenAIRE

Pinzón, I.D.

2015-01-01

El objetivo de este artículo es evaluar los efectos de un programa de entrenamiento funcional de músculos core dirigido a las mujeres con fibromialgia. Se realizó un ensayo cuasiexperimental de tipo antes y después de una intervención durante 20 semanas, con frecuencia de 3 días/semana y una duración de 60 minutos cada sesión. Los resultados sugieren que el programa de entrenamiento funcional de músculos core es eficaz en el aumento de la fuerza muscular, la modulación del dolor, la optimizac...

Spin transfer torque with spin diffusion in magnetic tunnel junctions

KAUST Repository

Manchon, Aurelien; Matsumoto, R.; Jaffres, H.; Grollier, J.

2012-01-01

in the metallic layers. We show that spin diffusion mixes the transverse spin current components and dramatically modifies the bias dependence of the effective spin transfer torque. This leads to a significant linear bias dependence of the out-of-plane torque

Evolução funcional de pacientes graves submetidos a um protocolo de reabilitação precoce

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Fernanda Murata Murakami

2015-06-01

Full Text Available RESUMO Objetivo: Avaliar a evolução funcional dos pacientes submetidos a um protocolo de reabilitação precoce do paciente grave da admissão até a alta da unidade de terapia intensiva. Métodos: Foi conduzido um estudo transversal retrospectivo, incluindo 463 pacientes adultos com diagnóstico clínico e/ou cirúrgico, submetidos a um protocolo de reabilitação precoce. A força muscular global foi avaliada na admissão da unidade de terapia intensiva por meio da escala Medical Research Council. De acordo com a pontuação da Medical Research Council os pacientes foram alocados em um dos quatro planos de intervenção, de acordo com a adequação ou não desses parâmetros, com a escala crescente do plano significando melhor status funcional. Os pacientes não colaborativos foram alocados nos planos de intervenção, conforme seu status funcional. A força muscular global e/ou o status funcional foram reavaliados na alta da unidade de terapia. Por meio do comparativo entre o plano de Intervenção na admissão (Planoinicial e na alta (Planofinal. Os pacientes foram categorizados em três grupos, de acordo com a melhora ou não do status funcional: respondedores 1 (Planofinal > Planoinicial, respondedores 2 (Planofinal = Planoinicial e não respondedores (Planofinal < Planoinicial. Resultados: Dos 463 pacientes submetidos ao protocolo, 432 (93,3% pacientes responderam positivamente à estratégia de intervenção, apresentando manutenção e/ou melhora do status funcional inicial. Os pacientes clínicos classificados como não respondedores apresentaram idade superior (74,3 ± 15,1 anos; p = 0,03 e maior tempo de internação na unidade de terapia intensiva (11,6 ± 14,2 dias; p = 0,047 e no hospital (34,5 ± 34,1 dias; p = 0,002. Conclusão: A manutenção e/ou melhora do status funcional admissional esteve associada com menor tempo de internação na unidade de terapia intensiva e hospitalar. Os resultados sugerem que o tipo de diagn

Spin Hall effect-driven spin torque in magnetic textures

KAUST Repository

Manchon, Aurelien; Lee, K.-J.

2011-01-01

Current-induced spin torque and magnetization dynamics in the presence of spin Hall effect in magnetic textures is studied theoretically. The local deviation of the charge current gives rise to a current-induced spin torque of the form (1 - ΒM) × [(u 0 + αH u 0 M) ∇] M, where u0 is the direction of the injected current, H is the Hall angle and is the non-adiabaticity parameter due to spin relaxation. Since αH and ×can have a comparable order of magnitude, we show that this torque can significantly modify the current-induced dynamics of both transverse and vortex walls. © 2011 American Institute of Physics.

Spin Hall effect-driven spin torque in magnetic textures

KAUST Repository

Manchon, Aurelien

2011-07-13

Current-induced spin torque and magnetization dynamics in the presence of spin Hall effect in magnetic textures is studied theoretically. The local deviation of the charge current gives rise to a current-induced spin torque of the form (1 - ΒM) × [(u 0 + αH u 0 M) ∇] M, where u0 is the direction of the injected current, H is the Hall angle and is the non-adiabaticity parameter due to spin relaxation. Since αH and ×can have a comparable order of magnitude, we show that this torque can significantly modify the current-induced dynamics of both transverse and vortex walls. © 2011 American Institute of Physics.

MODELAGEM PARA A MEDIÇÃO DE DESEMPENHO EM UM SISTEMA DE GESTÃO INTEGRADA SGI

OpenAIRE

Orlando Ferreira da Silveira

2015-01-01

Atualmente no mundo corporativo cresce o foco pela rapidez e intensidade com que se processam as mudanças, impulsionadas principalmente pelas frequentes inovações tecnológicas, pelo desempenho da economia e pela forte concorrência estabelecida no seu mercado de atuação. Diante desse cenário desafiador, surge a contínua necessidade de identificar novas técnicas, métodos e procedimentos, visando como principal meta da estratégia, melhorar o desempenho, a competitividade e a alavancagem da sua g...

Engine Torque Control of Spark Ignition Engine using Fuzzy Gain Scheduling

OpenAIRE

Aris Triwiyatno

2012-01-01

In the spark ignition engine system, driver convenience is very dependent on satisfying engine torque appropriate with the throttle position given by the driver. Unfortunately, sometimes the fulfillment of engine torque is not in line with fuel saving efforts. This requires the development of high performance and robust power train controllers. One way to potentially meet these performance requirements is to introduce a method of controlling engine torque using fuzzy gain scheduling. By using...

Mau desempenho escolar: uma visão atual Poor school performance: an updated review

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Cláudia Machado Siqueira

2011-02-01

Full Text Available Este estudo tem como objetivo uma revisão atualizada sobre o tema de mau desempenho escolar para profissionais da área de saúde e educação. Aborda aspectos atuais da educação, de aprendizagem e das principais condições envolvidas em mau desempenho escolar. Apresenta dados atualizados sobre os principais aspectos da neurobiologia, epidemiologia, etiologia, quadro clínico, comorbidades, diagnóstico, intervenção precoce e tratamento das principais patologias envolvidas. Trata-se de uma revisão abrangente, não sistemática da literatura sobre aprendizagem, desempenho escolar, transtorno de aprendizagem (dislexia, discalculia e disgrafia, transtorno de déficit de atenção/hiperatividade (TDA/H e transtorno de desenvolvimento de coordenação (TDC. O mau desempenho escolar é um sintoma frequente em nossas crianças com graves repercussões emocionais, sociais e econômicas. Uma visão atualizada do tema facilita o raciocínio clínico, o diagnóstico correto e o tratamento adequado.This study aims to develop a comprehensive review on the issue of poor school performance for professionals in both health and education areas. It discusses current aspects of education, learning and the main conditions involved in underachievement. It also presents updated data on key aspects of neurobiology, epidemiology, etiology, clinical presentation, comorbidities and diagnosis, early intervention and treatment of the major pathologies comprised. It is a comprehensive, non-systematic literature review on learning, school performance, learning disorders (dyslexia, dyscalculia and dysgraphia, attention deficit / hyperactivity disorder (ADHD and developmental coordination disorder (DCD. Poor school performance is a frequent problem faced by our children, causing serious emotional, social and economic issues. An updated view of the subject facilitates clinical reasoning, accurate diagnosis and appropriate treatment.

Medição de desempenho na construção civil: um estudo exploratório com construtoras cearenses

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Domingos Sávio Viana de Sousa

Full Text Available Resumo O presente trabalho tem por objetivo identificar as oportunidades de melhoria para a medição de desempenho a partir de um estudo de caso múltiplo com quatro construtoras de Fortaleza, CE. Para tal, foram realizadas dez entrevistas semiestruturadas com intervenientes de diferentes níveis hierárquicos das empresas, além de terem sido analisados documentos comprobatórios. Foram identificadas lacunas de desempenho, a partir das quais se realizou a proposição de onze melhorias para os processos das empresas estudadas e para a melhoria do campo do conhecimento em medição de desempenho. Conclui-se que, devido às deficiências observadas, os sistemas de medição não contribuem para a gestão das empresas efetivamente, uma vez que as informações geradas não conseguem enfatizar as verdadeiras lacunas de desempenho da empresa, bem como proporcionar um estilo de gestão proativo para as mudanças do mercado, o que diminui sua capacidade competitiva.

Gestão do desempenho humano: um estudo de caso em um Hospital Geral de Fortaleza (CE Administration of the human acting: a case study in a General Hospital of Fortaleza, Ceará State

Directory of Open Access Journals (Sweden)

Maria de Fátima Marrocos Fontenele

2010-06-01

Full Text Available A temática deste trabalho apresenta questões sobre a prática da avaliação de desempenho funcional em uma organização pública de saúde. Este eixo de análise ganha destaque a partir das dificuldades de desenvolvimento de sistemas de avaliação com alianças entre políticas de concessão de incentivos financeiros, em um contexto cultural peculiar. Nesse sentido, é necessário admitir os limites dessa ferramenta gerencial. A partir de uma pesquisa qualitativa, utilizou-se um roteiro semiestruturado de perguntas aplicado aos servidores de um hospital geral público do Estado do Ceará. Obteve-se a caracterização do sistema de avaliação de desempenho utilizado pela instituição, podendo-se verificar sua adequação aos modelos propostos na literatura e a pertinência de seus propósitos com as percepções e expectativas dos servidores pesquisados.The thematic of this work presents questions on the practice of the Evaluation of functional performance in an organization of public health. This axle of analysis gains importance from the difficulties of developing evaluation systems with alliances between policies of concession of financial incentives, in a specific cultural context. In this direction, it is necessary to admit the limits of this management tool. From a qualitative research, a semi-structured questionnaire was applied to the staff (public servers of a public general hospital of Ceará State. It was observed the characterization of the performance evaluation system used in the institution, being able to verify its adequacy to the models proposed in the literature and the relevancy of its intentions with the perceptions and expectations of the searched servers.

Estimation of Electrically-Evoked Knee Torque from Mechanomyography Using Support Vector Regression

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Morufu Olusola Ibitoye

2016-07-01

Full Text Available The difficulty of real-time muscle force or joint torque estimation during neuromuscular electrical stimulation (NMES in physical therapy and exercise science has motivated recent research interest in torque estimation from other muscle characteristics. This study investigated the accuracy of a computational intelligence technique for estimating NMES-evoked knee extension torque based on the Mechanomyographic signals (MMG of contracting muscles that were recorded from eight healthy males. Simulation of the knee torque was modelled via Support Vector Regression (SVR due to its good generalization ability in related fields. Inputs to the proposed model were MMG amplitude characteristics, the level of electrical stimulation or contraction intensity, and knee angle. Gaussian kernel function, as well as its optimal parameters were identified with the best performance measure and were applied as the SVR kernel function to build an effective knee torque estimation model. To train and test the model, the data were partitioned into training (70% and testing (30% subsets, respectively. The SVR estimation accuracy, based on the coefficient of determination (R2 between the actual and the estimated torque values was up to 94% and 89% during the training and testing cases, with root mean square errors (RMSE of 9.48 and 12.95, respectively. The knee torque estimations obtained using SVR modelling agreed well with the experimental data from an isokinetic dynamometer. These findings support the realization of a closed-loop NMES system for functional tasks using MMG as the feedback signal source and an SVR algorithm for joint torque estimation.

Determination of Ultimate Torque for Multiply Connected Cross Section Rod

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V. L. Danilov

2015-01-01

Full Text Available The aim of this work is to determine load-carrying capability of the multiply cross-section rod. This calculation is based on the model of the ideal plasticity of the material, so that the desired ultimate torque is a torque at which the entire cross section goes into a plastic state.The article discusses the cylindrical multiply cross-section rod. To satisfy the equilibrium equation and the condition of plasticity simultaneously, two stress function Ф and φ are introduced. By mathematical transformations it has been proved that Ф is constant along the path, and a formula to find its values on the contours has been obtained. The paper also presents the rationale of the line of stress discontinuity and obtained relationships, which allow us to derive the equations break lines for simple interaction of neighboring circuits, such as two lines, straight lines and circles, circles and a different sign of the curvature.After substitution into the boundary condition at the end of the stress function Ф and mathematical transformations a formula is obtained to determine the ultimate torque for the multiply cross-section rod.Using the doubly connected cross-section and three-connected cross-section rods as an example the application of the formula of ultimate torque is studied.For doubly connected cross-section rod, the paper offers a formula of the torque versus the radius of the rod, the aperture radius and the distance between their centers. It also clearly demonstrates the torque dependence both on the ratio of the radii and on the displacement of hole. It is shown that the value of the torque is more influenced by the displacement of hole, rather than by the ratio of the radii.For the three-connected cross-section rod the paper shows the integration feature that consists in selection of a coordinate system. As an example, the ultimate torque is found by two methods: analytical one and 3D modeling. The method of 3D modeling is based on the Nadai�

Variáveis contextuais como moderadoras da relação grh-desempenho organizacional: uma metanálise

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Agostinha Mafalda Barra de Oliveira

2014-06-01

Full Text Available Nas últimas décadas, muitos estudos têm sido realizados a fim de verificar a relação entre gestão de recursos humanos (GRH e desempenho organizacional. Revisores qualitativos e quantitativos dos resultados destes estudos concluíram que há uma relação positiva entre GRH e desempenho organizacional. No entanto, com base no alto índice de heterogeneidade apresentado nos resultados destes estudos, estes revisores apontaram para a interferência de variáveis contextuais nesta relação. Por este motivo, a fim de contribuir com o entendimento desta relação, testamos três modelos de variáveis moderadoras de tipo contextual: contexto geográfico, setor de atividade e tipos de empregados por meio de uma metanálise dos resultados de 194 registros de estudos empíricos sobre GRH e desempenho organizacional, realizados e/ou publicados entre 1985 e 2008. Das três variáveis testadas, confirmamos as variáveis: setor de atividade e contexto geográfico como moderadoras. Por outro lado, não confirmamos que a variável tipo de empregado é uma variável moderadora da relação GRH-desempenho organizacional.

Thermomagnetic torques in polyatomic gases

Science.gov (United States)

Hildebrandt, A. F.; Wood, C. T.

1972-01-01

The application of the Scott effect to the dynamics of galactic and stellar rotation is investigated. Efforts were also made to improve the sensitivity and stability of torque measurements and understand the microscopic mechanism that causes the Scott effect.

Optimum geometry for torque ripple minimization of switched reluctance motors

NARCIS (Netherlands)

Sahin, F.; Ertan, H.B.; Leblebicioglu, K.

2000-01-01

For switched reluctance motors, one of the major problems is torque ripple which causes increased undesirable acoustic noise and possibly speed ripple. This paper describes an approach to determine optimum magnetic circuit parameters to minimize low speed torque ripple for such motors. The

Desempenho operacional-financeiro e concentração de mercado sob o enfoque do paradigma estrutura-conduta-desempenho: um estudo exploratório na indústria brasileira de laticínios no período de 1997 a 2006

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Esmael Almeida Machado

2010-01-01

Full Text Available Estudos recentes indicam que o esperado processo de concentração de mercado na indústria de laticínios no país não se confirmou após a desregulamentação, ocorrida a partir do início dos anos 90. Neste cenário, considerando o paradigma da Estrutura-Conduta-Desempenho (ECD, a questão de pesquisa orienta este estudo é: O desempenho operacional e financeiro das empresas de laticínio no Brasil entre os anos de 1997 e 2006 influenciou os níveis de concentração do setor? Os indicadores de desempenho operacional e financeiro foram calculados com base no modelo Fleuriet (1978 e a análise da estrutura de mercado por meio do indicador de estimação da razão de concentração - CR(k - do setor para o período. O estudo é descritivo e a amostra intencional, dada a indisponibilidade de demonstrações financeiras para todas as empresas no período analisado. Os resultados da pesquisa sugerem que o desempenho das empresas, conforme os indicadores operacionais e financeiros, induz mudanças na estrutura de mercado e na posição das empresas - medidas pela razão de concentração CR(k.

ANÁLISE DO DESEMPENHO DE EMPRESAS DO SEGMENTO DE CARNES E DERIVADOS LISTADAS NA BM&FBOVESPA

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Simone Sehnem

2012-10-01

Full Text Available O objetivo do trabalho consiste em analisar o desempenho econômico e financeiro das empresas frigoríficas que negociam ações na BM&FBOVESPA em uma série histórica que compreende um período de 5 anos. A fundamentação teórica resgata aspectos relacionados a internacionalização de empresas e estudos que relacionam internacionalização e desempenho. O trabalho foi desenvolvido por meio da utilização de dados das empresas do segmento de carnes e derivados, isto é, frigoríficos, disponibilizados no economática e que negociam ações na BM&FBOVESPA. No que diz respeito à forma de abordagem do problema, a presente pesquisa trabalha sob o enfoque quantitativo e classifica-se em uma pesquisa de cunho descritivo. Com relação aos procedimentos, classifica-se em uma análise de uma série histórica do desempenho econômico e financeiro das organizações de capital aberto pertencentes ao segmento de frigoríficos, o que permite fazer um diagnóstico dessas empresas. As contribuições desta pesquisa consistem em elucidar que ficou perceptível que as empresas lideres do setor, quais sejam JBS Friboi, BR Foods e Marfrig, em sua maioria ocupam a liderança nos indicadores de desempenho econômico analisados. São empresas que cresceram e se internacionalizaram nos últimos anos, aumentando o patrimônio, a estrutura produtiva e os rendimentos. Possuem maior capacidade de competir, por terem estruturas de escala e unidades industriais distribuídas nos diferentes continentes, o que lhes aufere ganhos em detrimento das empresas de porte menor. Conclui-se que a internacionalização impacta de maneira forte no desempenho das organizações analisadas no presente estudo

Situación funcional, autopercepción de salud y nivel de actividad física en pacientes con artrosis

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Carmen Llanos Val Jiménez

2017-04-01

Conclusiones: En los pacientes con OA el dolor y la capacidad funcional son las dimensiones más afectadas. La situación funcional y la salud autopercibida son superiores en los pacientes activos, independientemente del número de articulaciones afectadas y de sus características sociodemográficas.

Desempenho acústico de paredes de blocos e tijolos cerâmico: uma comparação entre Brasil e Portugal

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Maria de Fatima Ferreira Neto

Full Text Available Alguns questionamentos sobre a relação entre desempenho acústico e o conforto acústico percebido contribuíram para o início desta pesquisa, que estuda o desempenho e conforto acústicos de ambientes compostos por blocos e tijolos cerâmicos, respectivamente no Brasil e em Portugal. Os tijolos portugueses apresentam 11,0 cm e 15,0 cm de espessura, enquanto os blocos brasileiros 11,5 cm e 14,0 cm de espessura. A avaliação do comportamento acústico desses elementos consistiu de testes em laboratório e em campo. Os critérios de desempenho utilizados para a avaliação do desempenho acústico foram a norma ABNT NBR 15575, do Brasil, e o Decreto-lei nº 96/2008, de Portugal. A avaliação do conforto acústico consistiu na análise da participação de um júri, que indicou a percepção de sentenças emitidas por vozes feminina e masculina, em simulação de convivência entre vizinhos adjacentes. Os resultados do desempenho acústico dessas paredes estão aquém do recomendado pelos critérios locais para o uso como parede de geminação. A avaliação dos resultados com o júri corroborou essa conclusão. Quanto ao desempenho acústico, verifica-se que a indústria da construção civil destes dois países deve aprimorar-se para atender aos critérios da nova norma.

Relação da Importância dos Recursos Estratégicos com as Medidas de Desempenho em Empresas Brasileiras

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Ilse Maria Beuren

2016-04-01

Full Text Available O estudo objetiva verificar se as medidas de desempenho são variáveis mediadoras entre a importância dos recursos estratégicos e a avaliação de desempenho em empresas brasileiras. De modo específico o estudo busca investigar a percepção dos gestores quanto à importância atribuída às medidas de desempenho tradicionais e não tradicionais e aos recursos estratégicos de capital humano, estrutural e físico em empresas brasileiras. O estudo pauta-se na pesquisa realizada por Widener (2006 em empresas norte americanas. Assim, um levantamento foi realizado junto aos gestores das empresas listadas na BM&FBovespa nos níveis 1 e 2 de Governança Corporativa. Na análise dos dados foi aplicada estatística descritiva e análise fatorial. Os resultados mostram que os gestores atribuem importância a várias medidas de desempenho, mas a estatística descritiva evidencia que a maior importância é atribuída às medidas de retorno e financeiras tradicionais. Dentre os recursos estratégicos, o capital humano desponta como o recurso mais importante para as empresas analisadas, seguido do capital estrutural e do capital físico. A partir das relações estabelecidas na pesquisa de base e aplicadas neste estudo, conclui-se que as medidas de desempenho são variáveis mediadoras entre a importância dos recursos estratégicos e o desempenho na percepção dos gestores.

Age-related reduction of trunk muscle torque and prevalence of trunk sarcopenia in community-dwelling elderly: Validity of a portable trunk muscle torque measurement instrument and its application to a large sample cohort study.

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Eiji Sasaki

Full Text Available Trunk muscle weakness and imbalance are risk factors for postural instability, low back pain, and poor postoperative outcomes. The association between trunk muscle strength and aging is poorly understood, and establishing normal reference values is difficult. We aimed to establish the validity of a novel portable trunk muscle torque measurement instrument (PTMI. We then estimated reference data for healthy young adults and elucidated age-related weakness in trunk muscle strength. Twenty-four university students were enrolled to validate values for PTMI, and 816 volunteers from the general population who were recruited to the Iwaki Health Promotion Project were included to estimate reference data for trunk muscle strength. Trunk flexion and extension torque were measured with PTMI and KinCom, and interclass correlation coefficients (ICC were estimated to evaluate the reliability of PTMI values. Furthermore, from the young adult reference, the age-related reduction in trunk muscle torque and the prevalence of sarcopenia among age-sex groups were estimated. The ICC in flexion and extension torque were 0.807 (p<0.001 and 0.789 (p<0.001, respectively. The prevalence of sarcopenia increased with age, and the prevalence due to flexion torque was double that of extension torque. Flexion torque decreased significantly after 60 years of age, and extension torque decreased after 70 years of age. In males over age 80, trunk muscle torque decreased to 49.1% in flexion and 63.5% in extension. In females over age 80, trunk muscle torque decreased to 60.7% in flexion and 68.4% in extension. The validity of PTMI was confirmed by correlation with KinCom. PTMI produced reference data for healthy young adults, and demonstrated age-related reduction in trunk muscle torque. Trunk sarcopenia progressed with aging, and the loss of flexion torque began earlier than extension torque. At age 80, trunk muscle torque had decreased 60% compared with healthy young adults.

Model analysis and experimental investigation of the friction torque during the CMP process

International Nuclear Information System (INIS)

Guo Dongming; Xu Chi; Kang Renke; Jin Zhuji

2011-01-01

A model for calculating friction torque during the chemical mechanical polishing (CMP) process is presented, and the friction force and torque detection experiments during the CMP process are carried out to verify the model. The results show that the model can well describe the feature of friction torque during CMP processing. The research results provide a theoretical foundation for the CMP endpoint detection method based on the change of the torque of the polishing head rotational spindle. (semiconductor technology)

Torque Split Strategy for Parallel Hybrid Electric Vehicles with an Integrated Starter Generator

OpenAIRE

Fu, Zhumu; Gao, Aiyun; Wang, Xiaohong; Song, Xiaona

2014-01-01

This paper presents a torque split strategy for parallel hybrid electric vehicles with an integrated starter generator (ISG-PHEV) by using fuzzy logic control. By combining the efficiency map and the optimum torque curve of the internal combustion engine (ICE) with the state of charge (SOC) of the batteries, the torque split strategy is designed, which manages the ICE within its peak efficiency region. Taking the quantified ICE torque, the quantified SOC of the batteries, and the quantified I...

Torques Induced by Scattered Pebble-flow in Protoplanetary Disks

Science.gov (United States)

Benítez-Llambay, Pablo; Pessah, Martin E.

2018-03-01

Fast inward migration of planetary cores is a common problem in the current planet formation paradigm. Even though dust is ubiquitous in protoplanetary disks, its dynamical role in the migration history of planetary embryos has not been assessed. In this Letter, we show that the scattered pebble-flow induced by a low-mass planetary embryo leads to an asymmetric dust-density distribution that is able to exert a net torque. By analyzing a large suite of multifluid hydrodynamical simulations addressing the interaction between the disk and a low-mass planet on a fixed circular orbit, and neglecting dust feedback onto the gas, we identify two different regimes, gas- and gravity-dominated, where the scattered pebble-flow results in almost all cases in positive torques. We collect our measurements in a first torque map for dusty disks, which will enable the incorporation of the effect of dust dynamics on migration into population synthesis models. Depending on the dust drift speed, the dust-to-gas mass ratio/distribution, and the embryo mass, the dust-induced torque has the potential to halt inward migration or even induce fast outward migration of planetary cores. We thus anticipate that dust-driven migration could play a dominant role during the formation history of planets. Because dust torques scale with disk metallicity, we propose that dust-driven outward migration may enhance the occurrence of distant giant planets in higher-metallicity systems.

Morfologia e contratilidade em cardiomiócitos de ratos com baixo desempenho para o exercício físico

Directory of Open Access Journals (Sweden)

Judson Fonseca Quintão Júnior

2012-05-01

Full Text Available FUNDAMENTO: A capacidade aeróbica é fundamental para o desempenho físico, e a baixa capacidade aeróbica está relacionada ao desencadeamento de diversas doenças cardiovasculares. OBJETIVO: Comparar a contratilidade e a morfologia de cardiomiócitos isolados de ratos com baixo desempenho e desempenho padrão para o exercício físico. MÉTODOS: Ratos Wistar, com 10 semanas de idade, foram submetidos a um protocolo de corrida em esteira até a fadiga, e foram divididos em dois grupos: Baixo Desempenho (BD e Desempenho Padrão (DP. Em seguida, após eutanásia, o coração foi removido rapidamente e, por meio de dissociação enzimática, os cardiomiócitos do ventrículo esquerdo foram isolados. O comprimento celular e dos sarcômeros e a largura dos cardiomiócitos foram medidos usando-se um sistema de detecção de bordas. Os cardiomiócitos isolados foram estimulados eletricamente a 1 e 3 Hz e a contração celular foi medida registrando-se a alteração do seu comprimento. RESULTADOS: O comprimento celular foi menor no grupo BD (157,2 ± 1,3µm; p < 0,05 em relação ao DP (161,4 ± 1,3 µm, sendo o mesmo resultado observado para o volume dos cardiomiócitos (BD, 25,5 ± 0,4 vs. DP, 26,8 ± 0,4 pL; p < 0,05. Os tempos para o pico de contração (BD, 116 ± 1 vs. DP, 111 ± 2ms e para o relaxamento total (BD, 143 ± 3 vs. DP, 232 ± 3 ms foram maiores no grupo BD. CONCLUSÃO: Conclui-se que os miócitos do ventrículo esquerdo dos animais de baixo desempenho para o exercício físico apresentam menores dimensões que os dos animais de desempenho padrão, além de apresentarem perdas na capacidade contrátil.

Intraoperative insertion torque of lumbar pedicle screw and postoperative radiographic evaluation. Short-term observation

International Nuclear Information System (INIS)

Mizuno, Koichi; Shinomiya, Kenichi; Otani, Kazuyuki

2005-01-01

The correlation between the insertion torque of a lumbar pedicle screw and the mechanical stability of the screw in the bone has been mentioned in in vitro studies. The purpose of this study was to confirm the factors affecting the insertion torque of such screws in vivo. Also, the contribution of insertion torque to the initial stability of the fusion area was to be analyzed in vivo. A series of 23 cases representing 50 lumbar vertebrae were included in this study, in which we examined bone mineral density using quantitative computed tomography (CT) prior to operation. Two screw shapes were utilized, with the insertion torque for each screw measured at two points in time. The correlation between insertion torque and mineral density was investigated. Screw positions were confirmed on postoperative CT scans, and the effect of the screw thread cutting into the cortex bone was investigated. Radiographic changes at three points during a period of 3 months were also measured, and we then evaluated the interrelations between these changes and insertion torque. Furthermore, the relation between insertion torque and instability at 3 months was investigated. Correlations of insertion torque and bone mineral density depended on screw shape. There was no correlation found with mineral density in the case of cylindrical screws. Insertion torque was not affected by the screw thread cutting into the cortex of bone. As for postoperative alignment changes, no definitive trends could be ascertained, and no interrelations with torque and alignment changes were observed. There is a possibility that insertion torque was related to early-stage stability, but no statistical relation could be determined. (author)

Spin-orbit-coupled transport and spin torque in a ferromagnetic heterostructure

KAUST Repository

Wang, Xuhui; Ortiz Pauyac, Christian; Manchon, Aurelien

2014-01-01

Ferromagnetic heterostructures provide an ideal platform to explore the nature of spin-orbit torques arising from the interplay mediated by itinerant electrons between a Rashba-type spin-orbit coupling and a ferromagnetic exchange interaction. For such a prototypic system, we develop a set of coupled diffusion equations to describe the diffusive spin dynamics and spin-orbit torques. We characterize the spin torque and its two prominent—out-of-plane and in-plane—components for a wide range of relative strength between the Rashba coupling and ferromagnetic exchange. The symmetry and angular dependence of the spin torque emerging from our simple Rashba model is in an agreement with experiments. The spin diffusion equation can be generalized to incorporate dynamic effects such as spin pumping and magnetic damping.

Spin-orbit-coupled transport and spin torque in a ferromagnetic heterostructure

KAUST Repository

Wang, Xuhui

2014-02-07

Ferromagnetic heterostructures provide an ideal platform to explore the nature of spin-orbit torques arising from the interplay mediated by itinerant electrons between a Rashba-type spin-orbit coupling and a ferromagnetic exchange interaction. For such a prototypic system, we develop a set of coupled diffusion equations to describe the diffusive spin dynamics and spin-orbit torques. We characterize the spin torque and its two prominent—out-of-plane and in-plane—components for a wide range of relative strength between the Rashba coupling and ferromagnetic exchange. The symmetry and angular dependence of the spin torque emerging from our simple Rashba model is in an agreement with experiments. The spin diffusion equation can be generalized to incorporate dynamic effects such as spin pumping and magnetic damping.

Current-induced spin transfer torque in ferromagnet-marginal Fermi liquid double tunnel junctions

International Nuclear Information System (INIS)

Mu Haifeng; Zheng Qingrong; Jin Biao; Su Gang

2005-01-01

Current-induced spin transfer torque through a marginal Fermi liquid (MFL) which is connected to two noncollinearly aligned ferromagnets via tunnel junctions is discussed in terms of the nonequilibrium Green function method. It is found that in the absence of the spin-flip scattering, the magnitude of the torque increases with the polarization and the coupling constant λ of the MFL, whose maximum increases with λ linearly, showing that the interactions between electrons tend to enhance the spin torque. When the spin-flip scattering is included, an additional spin torque is induced. It is found that the spin-flip scattering enhances the spin torque and gives rise to a nonlinear angular shift

Torque for electron spin induced by electron permanent electric dipole moment

Energy Technology Data Exchange (ETDEWEB)

Senami, Masato, E-mail: senami@me.kyoto-u.ac.jp, E-mail: akitomo@scl.kyoto-u.ac.jp; Fukuda, Masahiro, E-mail: senami@me.kyoto-u.ac.jp, E-mail: akitomo@scl.kyoto-u.ac.jp; Ogiso, Yoji, E-mail: senami@me.kyoto-u.ac.jp, E-mail: akitomo@scl.kyoto-u.ac.jp; Tachibana, Akitomo, E-mail: senami@me.kyoto-u.ac.jp, E-mail: akitomo@scl.kyoto-u.ac.jp [Department of Micro Engineering, Kyoto University, Kyoto 615-8540 (Japan)

2014-10-06

The spin torque of the electron is studied in relation to the electric dipole moment (EDM) of the electron. The spin dynamics is known to be given by the spin torque and the zeta force in quantum field theory. The effect of the EDM on the torque of the spin brings a new term in the equation of motion of the spin. We study this effect for a solution of the Dirac equation with electromagnetic field.

DESEMPENHO DE TERNEIROS DESMAMADOS PRECOCEMENTE E SUBMETIDOS A DIFERENTES SISTEMAS DE ALIMENTAÇÃO

Directory of Open Access Journals (Sweden)

Rubens Dorow

1994-01-01

Full Text Available RESUMO Este experimento foi conduzido na Fazenda Rincão em Cachoeira do Sul, RS; em convênio com a EMATER-RS e o Departamento de Zootecnia da Universidade Federal de Santa Maria, com o objetivo de avaliar o desempenho de temeiros de corte, medido em ganho de peso vivo, desde o desmame aos 90 dias até um ano de idade, quando submetidos a sistemas de alimentação baseados em pastagens naturais, pastagens de Digitaria decumbens Stent., Pennisetum americanum (L Schum. e Avena strigosa Schreb., combinadas entre si. Avaliou-se a qualidade e disponibilidade de matéria seca das pastagens associando-as ao desempenho dos temeiros desmamados aos 90 dias. Observou-se, nas condições em que foi realizado o experimento, que os temeiros alimentados com pastagens de milheto no verão e aveia no inverno, atingiram 187,75kg de peso vivo médio aos 12 meses de idade. As condições climáticas adversas do período experimental e o manejo animal impostos na Fazenda Rincão contribuíram para a redução na disponibilidade de matéria seca das pastagens, influenciando diretamente o desempenho dos animais.

Funciones y estructura de ingeniería social del nuevo gobierno local

Directory of Open Access Journals (Sweden)

José Vargas Hernández

2005-07-01

Full Text Available Este trabajo tiene como objetivo analizar las funciones y estructura de ingeniería social del nuevo gobierno local para dar respuesta a las demandas sociales, promover el desarrollo y regular los nuevos servicios públicos. A partir de una delimitación de los conceptos de soberanía y autonomía del nuevo gobierno local, se reconfigura una nueva estructura de gobernabilidad de los gobiernos locales que implica una mayor participación ciudadana en los procesos de toma de decisiones y la formulación de las políticas públicas, mediante la facilitación de procesos de descentralización de funciones y mecanismos coordinadores de servicios públicos. Finalmente se analizan las implicaciones en la gobernabilidad de la ingeniería social del nuevo gobierno local.

Funciones de sobrevivencia empleadas en el análisis demográfico

Directory of Open Access Journals (Sweden)

Alejandro Mina Valdés

2001-01-01

Full Text Available El manejo de las funciones de sobrevivencia tipo Gompertz y tipo Makeham son presentadas a partir de su origen, considerando sus antecedentes, así como la determinación de los parámetros de cada una de éstas, empleando para ello el método de los grupos no superpuestos, comunmente utilizado en ciencias actuariales. También se presenta el método iterativo que permite depurar, logrando un mejor ajuste, los resultados obtenidos, lo que permite proyectar los parámetros de las funciones de sobrevivencia, obteniendo tablas abreviadas de mortalidad por grupos quinquenales de edad tanto para los hombres como para las mujeres en México, a nivel nacional, para los años 1995, 2000, 2005 y 2010. Finalmente, se presentan las ganancias en las esperanzas por edad entre los años 1995 y 2010.

Aspectos conceituais e fatores associados ao Letramento Funcional em Saúde: revisão de literatura

Directory of Open Access Journals (Sweden)

Poliana Cristina Rocha

2016-02-01

Full Text Available RESUMO O objetivo deste estudo é revisar as produções científicas acerca da avaliação do letramento funcional em saúde em associação com a qualidade de vida; e analisar metodologicamente os estudos observacionais sobre a temática. Trata-se de revisão integrativa de literatura produzida com base em artigos relacionados aos seguintes eixos temáticos: letramento funcional em saúde e qualidade de vida, com busca realizada nas bases de dados PubMed, Lilacs, Biblioteca Virtual em Saúde. Após a aplicação dos critérios de inclusão obteve-se 538 artigos e após a aplicação dos critérios de exclusão foram selecionados 11 artigos sendo nove estudos internacionais e dois nacionais. A revisão constou de compilação e construção de linha histórica das publicações, análise metodológica dos estudos observacionais e elaboração de nuvem de textos. A maior parte dos artigos tem análise quantitativa; público alvo adultos e idosos e medem o nível de letramento funcional em saúde. Os estudos verificaram relação positiva do letramento funcional em saúde com a baixa escolaridade, idade mais avançada, sexo masculino e baixa renda. Os principais cenários foram ambientes assistenciais. O letramento funcional em saúde apresentou associação com variáveis sócio-demográficas como sexo, idade e escolaridade. A maior parte dos estudos encontrados na busca teve como objetivo relacionar o letramento a patologias e foi realizado em ambientes clínicos (ambulatórios e hospitais. Dos oito artigos observacionais incluídos na presente revisão atenderam totalmente aos critérios metodológicos para elaboração desse tipo de estudo.

Avaliação da capacidade funcional de idosos com acidente vascular encefálico Evaluación de la capacidad funcional de adultos mayores con accidente vascular encefálico Evaluation of functional capaciy in elders with encephalic vascular accident

Directory of Open Access Journals (Sweden)

Keila Cristianne Trindade da Cruz

2009-10-01

Full Text Available OBJETIVO: Avaliar a capacidade funcional de idosos com acidente vascular encefálico (AVE e verificar a relação, bem como a influência de variáveis sociodemográficas e de saúde na capacidade funcional desses sujeitos. MÉTODOS: Foram realizadas entrevistas com 44 idosos, vítimas de AVE, durante o atendimento nos locais de coleta de dados. O instrumento de coleta de dados contemplou dados sociodemográficos e clínicos. Para avaliar a capacidade funcional dos sujeitos foi aplicado o instrumento de Medida de Independência Funcional (MIF. RESULTADOS: Houve predomínio da faixa etária entre 60 e 69 anos. A MIF apresentou boa consistência interna. A pontuação total MIF dos apresentou média de 97,0. Os pacientes com acesso ao serviço de saúde apresentaram valores superiores aos dos indivíduos que não tinham acesso (Teste de Mann-Whitney. Foi observada correlação negativa entre a MIF e seus domínios e a idade (Pearson. CONCLUSÃO: O AVE causou alteração na capacidade funcional dos sujeitos da pesquisa, o que aponta para a necessidade de se investir em estratégias de reabilitação que venham a amenizar as perdas funcionais advindas da própria idade e, principalmente, das seqüelas de AVE.OBJETIVO: Evaluar la capacidad funcional de personas adultas mayores con accidente vascular encefálico (AVE y verificar la relación, así como la influencia de variables sociodemográficas y de salud en la capacidad funcional de esos sujetos. MÉTODOS: Fueron entrevistadas 44 personas adultas mayores, víctimas de AVE, durante la atención en los locales de recolección de datos. El instrumento de recolección de datos incluyó datos sociodemográficos y clínicos. Para evaluar la capacidad funcional de los sujetos se aplicó el instrumento de Medida de Independencia Funcional (MIF. RESULTADOS: Hubo predominio del grupo etáreo comprendido entre 60 y 69 años. La MIF presentó buena consistencia interna. La puntuación total de la MIF present

Avaliação de desempenho e motivação: o impacto das recompensas na motivação e obtenção de melhorias de desempenho, o caso da TranscorSV, S. A

OpenAIRE

Reis, Sandra Helena Graça

2009-01-01

A realização do presente estudo tem por intuito analisar o impacto das recompensas na motivação e obtenção de melhorias de desempenho. O estudo de caso inerente a este documento recaiu sobre uma empresa de transportes rodoviários de passageiros de Cabo Verde, a “Transcor SV, S.A.”. Os resultados acusaram que neste contexto organizacional, os trabalhadores do escritório e os controladores atribuem um impacto positivo às recompensas na motivação e obtenção de melhorias de desempenho, tendo s...

ANÁLISE DE DESEMPENHO EM REDES IEEE 802.3 APLICADO PARA SISTEMA DE TEMPO REAL

Directory of Open Access Journals (Sweden)

Ricardo Alexsandro de Medeiros Valentim

2011-06-01

Full Text Available A tecnologia Ethernet domina o mercado de rede local de computadores. No entanto, não foi estabelecida como uma tecnologia para automação industrial, onde o determinismo procura os requisitos com um desempenho de tempo real. Muitas soluções têm sido propostas para resolver o problema do determinismo não, que se baseiam principalmente no TDMA (acesso múltiplo por divisão de tempo, passagem de token e mestre-escravo. É neste contexto que este trabalho é realizado, através de medidas de desempenho em redes de comunicação que utilizam o padrão IEEE 802.3, observando o comportamento destas redes, quando submetidos a diferentes cenários de sobrecarga. Para isso, as variações foram aprovadas em ambiente de teste, que será baseado em Shared Ethernet (Hub, Ethernet e Ethernet Switch com prioridade (IEEE 802.1Q. Desta forma, é possível indicar quais os dispositivos analisados pelos testes de desempenho demonstrado um comportamento mais adequado para suportar as aplicações com requisitos de tempo real.

Metodologia de avaliação e desenvolvimento de grupos de alto desempenho

Directory of Open Access Journals (Sweden)

Ana Cristina Carneiro

2008-11-01

Full Text Available Este artigo discute a fundamentação teórica do Projeto de Avaliação e Desenvolvimento de Grupos de Alto Desempenho, concebido com base na metodologia da Meta-aprendizagem, e no Modelo Evolutivo, estendido à luz da Teoria da Complexidade. Visa ao desenvolvimento e aplicação de uma metodologia de avaliação/constituição de grupos de alto desempenho no ambiente de pesquisa e pós-graduação. A metodologia proposta validada empiricamente teve base no aproveitamento das virtudes e potencialidades das teorias que lhe deram origem. É destinado aos docentes e pesquisadores de vários campos do conhecimento, bem como aos dirigentes de instituições de educação superior e de pesquisa.

Improvement in torque and power transmission system of Savonius wind turbine

Energy Technology Data Exchange (ETDEWEB)

Ghosh, K.; Kumar, A.; Gupta, S. [Indian Inst. of Technology, Kanpur (India). Aerospace Engineering Dept.

2006-07-01

The Savonius vertical axis wind turbine has a simple geometry and is inexpensive to build due to its high power coefficient. However, because its torque coefficient varies widely with wind angles and even becomes negative twice in a revolution, it has not been widely commercialized. A Savonius rotor is conventionally built in 2 or 3 tiers, with 90-degree or 60-degree stagger between tiers for smoother torque. The torque coefficient versus wind angle data for multi-tier rotors can be generated by overlapping single-tier data with requisite stagger. This process ignores aerodynamic interference between tiers. The torque coefficient versus wind angle was measured in static mode and the power coefficient was measured in rotating mode of a 2-tier Savonius using a wind tunnel technique involving the brake-dynamometer principle and wind tunnel balance. A significant aerodynamic interference and lower power coefficient were observed. Static and dynamic testing procedures were described and smoke flow models and visualization were also presented. Subsequently, a discussion of the results of the testing were presented. It was concluded that there is significant aerodynamic interference between the tiers of a 2-tier model leading to reduced values of torque and power. Modification of the Savonius wind turbine by adding 20 per cent thick symmetrical airfoils results in improved torque, without significantly increasing average wake width. 3 refs., 1 tab., 13 refs.

Mechanics of Re-Torquing in Bolted Flange Connections

Science.gov (United States)

Gordon, Ali P.; Drilling Brian; Weichman, Kyle; Kammerer, Catherine; Baldwin, Frank

2010-01-01

It has been widely accepted that the phenomenon of time-dependent loosening of flange connections is a strong consequence of the viscous nature of the compression seal material. Characterizing the coupled interaction between gasket creep and elastic bolt stiffness has been useful in predicting conditions that facilitate leakage. Prior advances on this sub-class of bolted joints has lead to the development of (1) constitutive models for elastomerics, (2) initial tightening strategies, (3) etc. The effect of re-torque, which is a major consideration for typical bolted flange seals used on the Space Shuttle fleet, has not been fully characterized, however. The current study presents a systematic approach to characterizing bolted joint behavior as the consequence of sequentially applied torques. Based on exprimenta1 and numerical results, the optimal re-torquing parameters have been identified that allow for the negligible load loss after pre-load application

Vision system for dial gage torque wrench calibration

Science.gov (United States)

Aggarwal, Neelam; Doiron, Theodore D.; Sanghera, Paramjeet S.

1993-11-01

In this paper, we present the development of a fast and robust vision system which, in conjunction with the Dial Gage Calibration system developed by AKO Inc., will be used by the U.S. Army in calibrating dial gage torque wrenches. The vision system detects the change in the angular position of the dial pointer in a dial gage. The angular change is proportional to the applied torque. The input to the system is a sequence of images of the torque wrench dial gage taken at different dial pointer positions. The system then reports the angular difference between the different positions. The primary components of this vision system include modules for image acquisition, linear feature extraction and angle measurements. For each of these modules, several techniques were evaluated and the most applicable one was selected. This system has numerous other applications like vision systems to read and calibrate analog instruments.

Spin-transfer torque generated by a topological insulator

KAUST Repository

Mellnik, A. R.

2014-07-23

Magnetic devices are a leading contender for the implementation of memory and logic technologies that are non-volatile, that can scale to high density and high speed, and that do not wear out. However, widespread application of magnetic memory and logic devices will require the development of efficient mechanisms for reorienting their magnetization using the least possible current and power. There has been considerable recent progress in this effort; in particular, it has been discovered that spin-orbit interactions in heavy-metal/ferromagnet bilayers can produce strong current-driven torques on the magnetic layer, via the spin Hall effect in the heavy metal or the Rashba-Edelstein effect in the ferromagnet. In the search for materials to provide even more efficient spin-orbit-induced torques, some proposals have suggested topological insulators, which possess a surface state in which the effects of spin-orbit coupling are maximal in the sense that an electron\\' s spin orientation is fixed relative to its propagation direction. Here we report experiments showing that charge current flowing in-plane in a thin film of the topological insulator bismuth selenide (Bi2Se3) at room temperature can indeed exert a strong spin-transfer torque on an adjacent ferromagnetic permalloy (Ni81Fe19) thin film, with a direction consistent with that expected from the topological surface state. We find that the strength of the torque per unit charge current density in Bi 2Se3 is greater than for any source of spin-transfer torque measured so far, even for non-ideal topological insulator films in which the surface states coexist with bulk conduction. Our data suggest that topological insulators could enable very efficient electrical manipulation of magnetic materials at room temperature, for memory and logic applications. © 2014 Macmillan Publishers Limited. All rights reserved.

Intramuscular Pressure of Tibialis Anterior Reflects Ankle Torque but Does Not Follow Joint Angle-Torque Relationship

Directory of Open Access Journals (Sweden)

Filiz Ateş

2018-01-01

Full Text Available Intramuscular pressure (IMP is the hydrostatic fluid pressure that is directly related to muscle force production. Electromechanical delay (EMD provides a link between mechanical and electrophysiological quantities and IMP has potential to detect local electromechanical changes. The goal of this study was to assess the relationship of IMP with the mechanical and electrical characteristics of the tibialis anterior muscle (TA activity at different ankle positions. We hypothesized that (1 the TA IMP and the surface EMG (sEMG and fine-wire EMG (fwEMG correlate to ankle joint torque, (2 the isometric force of TA increases at increased muscle lengths, which were imposed by a change in ankle angle and IMP follows the length-tension relationship characteristics, and (3 the electromechanical delay (EMD is greater than the EMD of IMP during isometric contractions. Fourteen healthy adults [7 female; mean (SD age = 26.9 (4.2 years old with 25.9 (5.5 kg/m2 body mass index] performed (i three isometric dorsiflexion (DF maximum voluntary contraction (MVC and (ii three isometric DF ramp contractions from 0 to 80% MVC at rate of 15% MVC/second at DF, Neutral, and plantarflexion (PF positions. Ankle torque, IMP, TA fwEMG, and TA sEMG were measured simultaneously. The IMP, fwEMG, and sEMG were significantly correlated to the ankle torque during ramp contractions at each ankle position tested. This suggests that IMP captures in vivo mechanical properties of active muscles. The ankle torque changed significantly at different ankle positions however, the IMP did not reflect the change. This is explained with the opposing effects of higher compartmental pressure at DF in contrast to the increased force at PF position. Additionally, the onset of IMP activity is found to be significantly earlier than the onset of force which indicates that IMP can be designed to detect muscular changes in the course of neuromuscular diseases impairing electromechanical transmission.

Funciones Económicas en un Entorno Incierto

OpenAIRE

Lazzari, Luisa L; Chiodi, Jorge A; Moulia, Patricia I

2015-01-01

El mundo está atravesando una de las crisis económicas más profundas de los últimos tiempos. Los escenarios actuales y futuros están plagados de incertidumbre que, en general, no se considera en el análisis de las distintas funciones económicas de interés para el desarrollo del negocio, y la realidad se representa mediante modelos estáticos y casi perfectos del comportamiento de los mercados. La teoría de conjuntos borrosos permite construir modelos adecuados a partir de realidades inciertas ...

Funciones Orbitofrontales en pacientes con Demencia tipo Alzheimer

OpenAIRE

Solórzano Jiménez, Luis Mariano

2016-01-01

[ES] La DTA se caracteriza por el deterioro progresivo de la memoria y de otras áreas de la función cognitiva, tal es el caso de las funciones ejecutivas (FE), propias de la corteza prefrontal (CPF) y relacionadas con la autorregulación del comportamiento. De esta forma, los procesos asociados a las FE pueden ser de índole cognitivo (memoria de trabajo, razonamiento, resolución de problemas, planificación, secuenciación, atención sostenida, resistencia a la interferencia, utilización de feedb...

Desenvolvimento de um produto dietetico funcional para idosos.

OpenAIRE

Fabiane La Flor Ziegler

2006-01-01

Resumo: O principal objetivo da presente pesquisa foi desenvolver um produto dietético funcional para idosos desnutridos. Para tal, realizou-se inicialmente a caracterização físico-química e nutricional das fontes protéicas: isolado protéico do soro de leite bovino (WPI) e hidrolisado de colágeno bovino (HCB), buscando-se adequar a proporção entre elas, bem como, avaliar algumas de suas propriedades físicas, composição, perfil de aminoácidos e propriedade nutricional. Posteriormente foi reali...

Alteraciones de la conectividad funcional en la esquizofrenia

OpenAIRE

Rodríguez de la Pinta, Cristina

2016-01-01

La esquizofrenia, es uno de los trastornos psicóticos más prevalente y grave a nivel mundial. La idea de este trabajo es revisar algunos de los artículos publicados acerca de la conectividad en esta enfermedad, ofreciendo así una visión del funcionamiento cerebral de estos pacientes. No hay nada definitivo aún, pero la gran mayoría de los estudios coinciden en que la alteración de la conectividad funcional entre las diferentes redes neuronales es una de las bases fundamental...

Inertial torque during reaching directly impacts grip-force adaptation to weightless objects.

Science.gov (United States)

Giard, T; Crevecoeur, F; McIntyre, J; Thonnard, J-L; Lefèvre, P

2015-11-01

A hallmark of movement control expressed by healthy humans is the ability to gradually improve motor performance through learning. In the context of object manipulation, previous work has shown that the presence of a torque load has a direct impact on grip-force control, characterized by a significantly slower grip-force adjustment across lifting movements. The origin of this slower adaptation rate remains unclear. On the one hand, information about tangential constraints during stationary holding may be difficult to extract in the presence of a torque. On the other hand, inertial torque experienced during movement may also potentially disrupt the grip-force adjustments, as the dynamical constraints clearly differ from the situation when no torque load is present. To address the influence of inertial torque loads, we instructed healthy adults to perform visually guided reaching movements in weightlessness while holding an unbalanced object relative to the grip axis. Weightlessness offered the possibility to remove gravitational constraints and isolate the effect of movement-related feedback on grip force adjustments. Grip-force adaptation rates were compared with a control group who manipulated a balanced object without any torque load and also in weightlessness. Our results clearly show that grip-force adaptation in the presence of a torque load is significantly slower, which suggests that the presence of torque loads experienced during movement may alter our internal estimates of how much force is required to hold an unbalanced object stable. This observation may explain why grasping objects around the expected location of the center of mass is such an important component of planning and control of manipulation tasks.

Controlling torque and cutting costs: steerable drill bits deliver in Latin America

Energy Technology Data Exchange (ETDEWEB)

Barton, Steve; Garcia, Alexis; Amorim, Dalmo [ReedHycalog, Stonehouse (United Kingdom); Iramina, Wilson [University of Sao Paulo (USP), SP (Brazil); Herrera, Gabriel

2008-07-01

Tool face Control is widely regarded as one of the greatest directional drilling challenges with a Fixed Cutter (FC) drill bit on a Steerable Motor assembly. Tool face offset is proportional to the torque generated by the bit, and by nature, FC bits are capable of generating high levels of torque. If large changes in downhole torque are produced while drilling, this will cause rotation of the drill string, and loss of tool face orientation. This results in inefficient drilling and increases risk of bit and downhole tool damage. This paper examines the effect of various FC drill bit components to determine the key design requirements to deliver a smooth torque response and an improved directional performance. Included is a review of the results from comprehensive laboratory testing to determine the effectiveness of a number of different configurations of removable Torque Controlling Components (TCC). These, in combination with specific cutting structure layouts, combine to provide predictable torque response while optimized for high rates of penetration. In addition, unique gauge geometry is disclosed that was engineered to reduce drag and deliver improved borehole quality. This gauge design produces less torque when sliding and beneficial gauge pad interaction with the borehole when in rotating mode. Field performance studies from within Latin America clearly demonstrate that matching TCC, an optimized cutting structure, and gauge geometry to a steerable assembly delivers smooth torque response and improved directional control. Benefits with regard to improved stability are also discussed. Successful application has resulted in significant time and cost savings for the operator, demonstrating that Stability and Steerability improvements can be achieved with an increase in penetration rate. (author)

Balancing of a power-transmission shaft with the application of axial torque

Science.gov (United States)

Zorzi, E. S.; Flemming, D.

1980-01-01

Evaluation of power transmission shafting for high-speed balancing has shown that when axial torque is applied, the imbalance response is altered. An increase in synchronous excitation always occurs if the axial torque level is altered from the value used during balancing; this was the case even when the shaft was balanced with torque applied. The twisting of the long slender shaft produces a change in the imbalance distribution sufficient to disrupt the balanced state. This paper presents a review of the analytic development of a weighted least squares approach to influence coefficient balancing and a review of experimental results. The analytic approach takes advantage of the fact that the past testing has shown that the influence coefficients are not significantly affected by the application of axial torque. The 3.60-m (12-ft) long aluminum shaft, 7.62 cm (3 in.) in diameter was run through the first flexural critical speed at torque levels ranging from zero-torque to 903.8 N-M (8000 lb-in.) in 112.9 N-M (1000 lb-in.) increments. Good comparison was achieved between predicted and experimental results.

Immediate effects of whole body vibration on patellar tendon properties and knee extension torque.

Science.gov (United States)

Rieder, F; Wiesinger, H-P; Kösters, A; Müller, E; Seynnes, O R

2016-03-01

Reports about the immediate effects of whole body vibration (WBV) exposure upon torque production capacity are inconsistent. However, the changes in the torque-angle relationship observed by some authors after WBV may hinder the measurement of torque changes at a given angle. Acute changes in tendon mechanical properties do occur after certain types of exercise but this hypothesis has never been tested after a bout of WBV. The purpose of the present study was to investigate whether tendon compliance is altered immediately after WBV, effectively shifting the optimal angle of peak torque towards longer muscle length. Twenty-eight subjects were randomly assigned to either a WBV (n = 14) or a squatting control group (n = 14). Patellar tendon CSA, stiffness and Young's modulus and knee extension torque-angle relationship were measured using ultrasonography and dynamometry 1 day before and directly after the intervention. Tendon CSA was additionally measured 24 h after the intervention to check for possible delayed onset of swelling. The vibration intervention had no effects on patellar tendon CSA, stiffness and Young's modulus or the torque-angle relationship. Peak torque was produced at ~70° knee angle in both groups at pre- and post-test. Additionally, the knee extension torque globally remained unaffected with the exception of a small (-6%) reduction in isometric torque at a joint angle of 60°. The present results indicate that a single bout of vibration exposure does not substantially alter patellar tendon properties or the torque-angle relationship of knee extensors.

Accretion torques due to three-dimensional channelled flows in magnetic cataclysmic variables

International Nuclear Information System (INIS)

Campbell, C.G.

1986-01-01

Angular momentum transfer due to three-dimensional magnetically channelled accretion flows in cataclysmic binaries is considered. The white dwarf experiences a torque due to the twist in that part of its magnetic field which interacts with the accretion stream. The channelling process can also enhance angular momentum exchange between the stream and the orbit by increasing the gravitational torques. The components of the accretion torque are calculated for an arbitrary static magnetic orientation of the white dwarf, and their variation with orientation is presented. For high inclinations of the accreting pole to the orbital plane the component of the accretion torque parallel to this plane can be comparable to its perpendicular component. It is shown that the parallel component of the torque is still significant relative to the perpendicular component if material links to the white dwarf's magnetic field well away from the L 1 region. (author)

Comportamento estratégico e desempenho: um estudo aplicado nas indústrias vinícolas de Portugal

OpenAIRE

Elvis Silveira-Martins; Universidade Federal de Pelotas - UFPel; Marcelo Oliveira Basso; Universidade Federal de Pelotas - UFPel; Luiz Eduardo Mascarenhas; Universidade Federal de Pelotas - UFPel

2014-01-01

Os objetivos deste estudo estão direcionados a: i) identificar as tipologias de comportamento estratégico presentes nas indústrias vinícolas portuguesas; e; ii) analisar se existem diferenças significantes entre os comportamentos estratégicos e o desempenho das organizações. O marco teórico está ancorado nos construtos comportamento estratégico, em especifico na tipologia de Miles e Snow (1978), e desempenho organizacional. A presente pesquisa valeu-se da abordagem quantitativa e da estratégi...

Explosive sport training and torque kinetics in children.

Science.gov (United States)

Dotan, Raffy; Mitchell, Cameron J; Cohen, Rotem; Gabriel, David; Klentrou, Panagiota; Falk, Bareket

2013-07-01

A high rate of force development (RFD) is often more important than maximal force in daily and sports activities. In children, resistance training has been shown to increase maximal force. It is unclear whether, or to what extent, can children improve RFD and force kinetics. For this study, we compared strength and force kinetics of boy gymnasts with those of untrained boys and untrained men. Eight boy gymnasts (age, 9.5 ± 1.2 y), 20 untrained boys (age, 10.1 ± 1.3 y), and 20 untrained men (age, 22.9 ± 4.4 y) performed maximal, explosive, isometric elbow flexions (EF) and knee flexions (KF). Peak torque (maximal voluntary contraction (MVC)), elapsed times to 10%-100% MVC, peak rate of torque development (RTDpk), and other kinetics parameters were determined. When gymnasts were compared with untrained boys, size-normalized EF MVC was 11%-20% higher, RTDpk was 32% higher, and times to 30% and 80% MVC were 16% and 55% shorter, respectively (p kinetics parameters were similar. These findings highlight the specificity of gymnastics training, which markedly elevated the torque kinetics of young, prepubertal boys to adult levels, but only moderately affected peak torque. It is suggested that neurologic adaptations, such as enhanced firing and activation rates or increased type II motor-unit recruitment, as well as changes in musculotendinous stiffness, could explain these findings.

Angular dependence and symmetry of Rashba spin torque in ferromagnetic heterostructures

KAUST Repository

Ortiz Pauyac, Christian

2013-06-26

In a ferromagnetic heterostructure, the interplay between Rashba spin-orbit coupling and exchange splitting gives rise to a current-driven spin torque. In a realistic device setup, we investigate the Rashba spin torque in the diffusive regime and report two major findings: (i) a nonvanishing torque exists at the edges of the device even when the magnetization and effective Rashba field are aligned; (ii) anisotropic spin relaxation rates driven by the Rashba spin-orbit coupling assign the spin torque a general expression T = T y (θ) m × (y × m) + T y (θ) y × m + T z (θ) m × (z × m) + T z (θ) z × m, where the coefficients T, y, z depend on the magnetization direction. Our results agree with recent experiments. © 2013 AIP Publishing LLC.

Angular dependence and symmetry of Rashba spin torque in ferromagnetic heterostructures

KAUST Repository

Ortiz Pauyac, Christian; Wang, Xuhui; Chshiev, Mairbek; Manchon, Aurelien

2013-01-01

In a ferromagnetic heterostructure, the interplay between Rashba spin-orbit coupling and exchange splitting gives rise to a current-driven spin torque. In a realistic device setup, we investigate the Rashba spin torque in the diffusive regime and report two major findings: (i) a nonvanishing torque exists at the edges of the device even when the magnetization and effective Rashba field are aligned; (ii) anisotropic spin relaxation rates driven by the Rashba spin-orbit coupling assign the spin torque a general expression T = T y (θ) m × (y × m) + T y (θ) y × m + T z (θ) m × (z × m) + T z (θ) z × m, where the coefficients T, y, z depend on the magnetization direction. Our results agree with recent experiments. © 2013 AIP Publishing LLC.

Skinfold thickness affects the isometric knee extension torque evoked by Neuromuscular Electrical Stimulation.

Science.gov (United States)

Medeiros, Flávia V A; Vieira, Amilton; Carregaro, Rodrigo L; Bottaro, Martim; Maffiuletti, Nicola A; Durigan, João L Q

2015-01-01

Subcutaneous adipose tissue may influence the transmission of electrical stimuli through to the skin, thus affecting both evoked torque and comfort perception associated with neuromuscular electrical stimulation (NMES). This could seriously affect the effectiveness of NMES for either rehabilitation or sports purposes. To investigate the effects of skinfold thickness (SFT) on maximal NMES current intensity, NMES-evoked torque, and NMES-induced discomfort. First, we compared NMES current intensity, NMES-induced discomfort, and NMES-evoked torque between two subgroups of subjects with thicker (n=10; 20.7 mm) vs. thinner (n=10; 29.4 mm) SFT. Second, we correlated SFT to NMES current intensity, NMES-induced discomfort, and NMES-evoked knee extension torque in 20 healthy women. The NMES-evoked torque was normalized to the maximal voluntary contraction (MVC) torque. The discomfort induced by NMES was assessed with a visual analog scale (VAS). NMES-evoked torque was 27.5% lower in subjects with thicker SFT (p=0.01) while maximal current intensity was 24.2% lower in subjects with thinner SFT (p=0.01). A positive correlation was found between current intensity and SFT (r=0.540, p=0.017). A negative correlation was found between NMES-evoked torque and SFT (r=-0.563, p=0.012). No significant correlation was observed between discomfort scores and SFT (rs=0.15, p=0.53). These results suggest that the amount of subcutaneous adipose tissue (as reflected by skinfold thickness) affected NMES current intensity and NMES-evoked torque, but had no effect on discomfort perception. Our findings may help physical therapists to better understand the impact of SFT on NMES and to design more rational stimulation strategies.

The relationship between social support and functional capacity in elderly persons with cognitive alterations Relación entre apoyo social y capacidad funcional de los mayores con los cambios cognitivos Relação entre apoio social e capacidade funcional de idosos com alterações cognitivas

Directory of Open Access Journals (Sweden)

Tábatta Renata Pereira de Brito

2012-08-01

mantener su capacidad funcional, y garantizar relaciones sociales satisfactorias.O objetivo deste trabalho foi identificar a relação entre o apoio social e a capacidade funcional de idosos com alterações cognitivas. Trata-se de estudo descritivo, transversal, quantitativo. Os sujeitos foram 101 idosos cadastrados em Unidades de Saúde da Família que apresentaram desempenho no Mini Exame do Estado Mental abaixo da nota de corte em estudo anterior. Aplicaram-se o Medical Outcomes Study, Índice de Katz e Questionário de Atividades Funcionais de Pfeffer. As dimensões de apoio material, afetivo, emocional, de informação e de interação social positiva resultaram em um escore final médio de 74,43 pontos, indicando melhor nível de apoio material e afetivo em relação às demais dimensões de apoio. Houve correlação estatisticamente significativa entre o apoio emocional e o Índice de Katz. O conhecimento dessa relação favorece o desenvolvimento de uma linha de cuidado em enfermagem ao idoso capaz de manter sua capacidade funcional e garantir relações sociais satisfatórias.

Effect of Filament Fineness on Composite Yarn Residual Torque

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Sarıoğlu Esin

2018-03-01

Full Text Available Yarn residual torque or twist liveliness occurs when the twist is imparted to spin the fibers during yarn formation. It causes yarn snarling, which is an undesirable property and can lead the problems for further processes such as weaving and knitting. It affects the spirality of knitted fabrics and skewness of woven fabrics. Generally, yarn residual torque depends on yarn twist, yarn linear density, and fiber properties used. Composite yarns are widely produced to exploit two yarns with different properties such on optimum way at the same time and these yarns can be produced by wrapping sheath fibers around filament core fiber with a certain twist. In this study, the effect of filament fineness used as core component of composite yarn on residual torque was analyzed. Thus, the false twist textured polyester filament yarns with different filament fineness were used to produce composite yarns with different yarn count. The variance analysis was performed to determine the significance of twist liveliness of filament yarns and yarn count on yarn twist liveliness. Results showed that there is a statistically significant differences at significance level of α=0.05 between filament fineness and yarn residual torque of composite yarns.

Knee extension torque variability after exercise in ACL reconstructed knees.

Science.gov (United States)

Goetschius, John; Kuenze, Christopher M; Hart, Joseph M

2015-08-01

The purpose of this study was to compare knee extension torque variability in patients with ACL reconstructed knees before and after exercise. Thirty two patients with an ACL reconstructed knee (ACL-R group) and 32 healthy controls (control group) completed measures of maximal isometric knee extension torque (90° flexion) at baseline and following a 30-min exercise protocol (post-exercise). Exercise included 30-min of repeated cycles of inclined treadmill walking and hopping tasks. Dependent variables were the coefficient of variation (CV) and raw-change in CV (ΔCV): CV = (torque standard deviation/torque mean x 100), ΔCV = (post-exercise - baseline). There was a group-by-time interaction (p = 0.03) on CV. The ACL-R group demonstrated greater CV than the control group at baseline (ACL-R = 1.07 ± 0.55, control = 0.79 ± 0.42, p = 0.03) and post-exercise (ACL-R = 1.60 ± 0.91, control = 0.94 ± 0.41, p = 0.001). ΔCV was greater (p = 0.03) in the ACL-R group (0.52 ± 0.82) than control group (0.15 ± 0.46). CV significantly increased from baseline to post-exercise (p = 0.001) in the ACL-R group, while the control group did not (p = 0.06). The ACL-R group demonstrated greater knee extension torque variability than the control group. Exercise increased torque variability more in the ACL-R group than control group. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

Resistive wall tearing mode generated finite net electromagnetic torque in a static plasma

International Nuclear Information System (INIS)

Hao, G. Z.; Wang, A. K.; Xu, M.; Qu, H. P.; Peng, X. D.; Wang, Z. H.; Xu, J. Q.; Qiu, X. M.; Liu, Y. Q.

2014-01-01

The MARS-F code [Y. Q. Liu et al., Phys. Plasmas 7, 3681 (2000)] is applied to numerically investigate the effect of the plasma pressure on the tearing mode stability as well as the tearing mode-induced electromagnetic torque, in the presence of a resistive wall. The tearing mode with a complex eigenvalue, resulted from the favorable averaged curvature effect [A. H. Glasser et al., Phys. Fluids 18, 875 (1975)], leads to a re-distribution of the electromagnetic torque with multiple peaking in the immediate vicinity of the resistive layer. The multiple peaking is often caused by the sound wave resonances. In the presence of a resistive wall surrounding the plasma, a rotating tearing mode can generate a finite net electromagnetic torque acting on the static plasma column. Meanwhile, an equal but opposite torque is generated in the resistive wall, thus conserving the total momentum of the whole plasma-wall system. The direction of the net torque on the plasma is always opposite to the real frequency of the mode, agreeing with the analytic result by Pustovitov [Nucl. Fusion 47, 1583 (2007)]. When the wall time is close to the oscillating time of the tearing mode, the finite net torque reaches its maximum. Without wall or with an ideal wall, no net torque on the static plasma is generated by the tearing mode. However, re-distribution of the torque density in the resistive layer still occurs

Orion - Super Koropon(Registered Trademark) Torque/Tension Report

Science.gov (United States)

Hemminger, Edgar G.; McLeod, Christopher; Peil, John

2012-01-01

The primary objective of this testing was to obtain torque tension data for the use of Super Koropon Primer Base which was proposed for use on the Orion project. This compound is a corrosion inhibitor/sealer used on threaded fasteners and inserts as specified per NASA/JSC PRC-4004, Sealing of Joints and Faying Surfaces. Some secondary objectives of this testing, were to identify the effect on torque coefficient of several variables. This document contains the outcome of the testing.

Torque Tension Testing of Fasteners used for NASA Flight Hardware Applications

Science.gov (United States)

Hemminger, Edgar G.; Posey, Alan J.; Dube, Michael J.

2014-01-01

The effect of various lubricants and other compounds on fastener torque-tension relationships is evaluated. Testing was performed using a unique test apparatus developed by Posey at the NASA Goddard Space Flight Center. A description of the test methodology, including associated data collection and analysis will be presented. Test results for 300 series CRES and A286 heat resistant fasteners, torqued into various types of inserts will be presented. The primary objective of this testing was to obtain torque-tension data for use on NASA flight projects.

Electromagnetic forces and torques in nanoparticles irradiated by plane waves

International Nuclear Information System (INIS)

Garcia de Abajo, F.J.

2004-01-01

Optical tweezers and optical lattices are making it possible to control small particles by means of electromagnetic forces and torques. In this context, a method is presented in this work to calculate electromagnetic forces and torques for arbitrarily-shaped objects in the presence of other objects illuminated by a plane wave. The method is based upon an expansion of the electromagnetic field in terms of multipoles around each object, which are in turn used to derive forces and torques analytically. The calculation of multipole coefficients are obtained numerically by means of the boundary element method. Results are presented for both spherical and non-spherical objects

Shot noise of spin current and spin transfer torque

International Nuclear Information System (INIS)

Yu Yunjin; Zhan Hongxin; Wan Langhui; Wang Bin; Wei Yadong; Sun Qingfeng; Wang Jian

2013-01-01

We report the theoretical investigation of the shot noise of the spin current (S σ ) and the spin transfer torque (S τ ) for non-collinear spin polarized transport in a spin-valve device which consists of a normal scattering region connected by two ferromagnetic electrodes (MNM system). Our theory was developed using the non-equilibrium Green’s function method, and general nonlinear S σ − V and S τ − V relations were derived as a function of the angle θ between the magnetizations of two leads. We have applied our theory to a quantum dot system with a resonant level coupled with two ferromagnetic electrodes. It was found that, for the MNM system, the auto-correlation of the spin current is enough to characterize the fluctuation of the spin current. For a system with three ferromagnetic layers, however, both auto-correlation and cross-correlation of the spin current are needed to characterize the noise of the spin current. For a quantum dot with a resonant level, the derivative of spin torque with respect to bias voltage is proportional to sinθ when the system is far away from resonance. When the system is near resonance, the spin transfer torque becomes a non-sinusoidal function of θ. The derivative of the noise of the spin transfer torque with respect to the bias voltage N τ behaves differently when the system is near or far away from resonance. Specifically, the differential shot noise of the spin transfer torque N τ is a concave function of θ near resonance while it becomes a convex function of θ far away from resonance. For certain bias voltages, the period N τ (θ) becomes π instead of 2π. For small θ, it was found that the differential shot noise of the spin transfer torque is very sensitive to the bias voltage and the other system parameters. (paper)

Sensorless Speed/Torque Control of DC Machine Using Artificial Neural Network Technique

Directory of Open Access Journals (Sweden)

Rakan Kh. Antar

2017-12-01

Full Text Available In this paper, Artificial Neural Network (ANN technique is implemented to improve speed and torque control of a separately excited DC machine drive. The speed and torque sensorless scheme based on ANN is estimated adaptively. The proposed controller is designed to estimate rotor speed and mechanical load torque as a Model Reference Adaptive System (MRAS method for DC machine. The DC drive system consists of four quadrant DC/DC chopper with MOSFET transistors, ANN, logic gates and routing circuits. The DC drive circuit is designed, evaluated and modeled by Matlab/Simulink in the forward and reverse operation modes as a motor and generator, respectively. The DC drive system is simulated at different speed values (±1200 rpm and mechanical torque (±7 N.m in steady state and dynamic conditions. The simulation results illustratethe effectiveness of the proposed controller without speed or torque sensors.

Torque expression in self-ligating orthodontic brackets and conventionally ligated brackets: A systematic review.

Science.gov (United States)

Al-Thomali, Yousef; Mohamed, Roshan-Noor; Basha, Sakeenabi

2017-01-01

To evaluate the torque expression of self ligating (SL) orthodontic brackets and conventionally ligated brackets and the torque expression in active and passive SL brackets. Our systematic search included MEDLINE, EMBASE, CINAHL, PsychINFO, Scopus, and key journals and review articles; the date of the last search was April 4th 2016. We graded the methodological quality of the studies by means of the Quality Assessment Tool for Quantitative Studies, developed for the Effective Public Health Practice Project (EPHPP). In total, 87 studies were identified for screening, and 9 studies were eligible. The quality assessment rated one of the study as being of strong quality, 7 (77.78%) of these studies as being of moderate quality. Three out of 7 studies which compared SL and conventionally ligated brackets showed, conventionally ligated brackets with highest torque expression compared to SL brackets. Badawi showed active SL brackets with highest torque expression compared to passive SL brackets. Major and Brauchli showed no significant differences in torque expression of active and passive SL brackets. Conventionally ligated brackets presented with highest torque expression compared to SL brackets. Minor difference was recorded in a torque expression of active and passive SL brackets. Key words: Systematic review, self ligation, torque expression, conventional ligation.

A contribuição da prática do handebol no desempenho das habilidades motoras amplas de escolares

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Mateus De Lucca

2011-09-01

Full Text Available O presente estudo teve como objetivo investigar o papel da prática do handebol no desempenho de habilidades motoras amplas de escolares. Métodos: Participaram do estudo 26 crianças, com 10 anos de idade, sendo que 13 praticavam a modalidade de handebol mais as aulas de Educação Física e 13 participavam apenas das aulas de Educação Física. Para a avaliação do desempenho motor dos escolares foi o utilizado o TGMD-2 proposto por Ulrich. Na analise estatística foi utilizado o teste não paramétrico e na comparação entre os grupos foi utilizado U Mann-Whitney. Resultados: a maioria dos escolares que pratica o handebol apresentou desempenho considerado na Média nos escores de locomoção e controle de objetos enquanto que a maior parte do grupo que participou somente das aulas de educação física demonstrou desempenho abaixo da média e fraco nestas variáveis. Quando comparadas as habilidades motoras entre os grupos percebeu-se diferenças estatísticas nas habilidades de corrida (p

Torque vectoring for improving stability of small electric vehicles

Science.gov (United States)

Grzegożek, W.; Weigel-Milleret, K.

2016-09-01

The electric vehicles solutions based on the individually controlled electric motors propel a single wheel allow to improve the dynamic properties of the vehicle by varying the distribution of the driving torque. Most of the literature refer to the vehicles with a track typical for passenger cars. This paper examines whether the narrow vehicle (with a very small track) torque vectoring bring a noticeable change of the understeer characteristics and whether torque vectoring is possible to use in securing a narrow vehicle from roll over (roll mitigation). The paper contains road tests of the steering characteristics (steady state understeer characteristic quasi-static acceleration with a fixed steering wheel (SH = const) and on the constant radius track (R = const)) of the narrow vehicle. The vehicle understeer characteristic as a function of a power distribution is presented.

Redes Atm de Alto Desempenho

Directory of Open Access Journals (Sweden)

Flávia Oliveira Santos de Sá Lisboa

2015-12-01

Full Text Available A tendência atual de integração de serviços de dados, voz e vídeo, estimulada pelo pleno sucesso da Internet, aumentou a demanda por maior banda e melhor desempenho nas redes de comunicação de dados. Neste contexto, a tecnologia ATM (Asynchronous Transfer Mode vem sendo utilizada na implementação de backbone de LANs e WANs, justamente por oferecer a possibilidade de integração de serviços com qualidade, alta escalabilidade e altas taxas de transferência em banda larga. Neste artigo serão abordados os principais conceitos relacionados à tecnologia ATM, suas vantagens e desvantagens em face de outras tecnologias (como Fast e Gigabit Ethernet, além de casos de sua utilização em empresas e instituições de ensino.

Speed sensorless direct torque control of IMs with rotor resistance estimation

International Nuclear Information System (INIS)

Barut, Murat; Bogosyan, Seta; Gokasan, Metin

2005-01-01

Direct torque control (DTC) of induction motors (IMs) requires an accurate knowledge on the amplitude and angular position of the controlled flux in addition to the information related to angular velocity for velocity control applications. However, unknown load torque and uncertainties related to stator/rotor resistances due to operating conditions constitute major challenges for the performance of such systems. The determination of stator resistance can be performed by measurements, but methods must be developed for estimation and identification of rotor resistance and load torque. In this study, an EKF based solution is sought for determination of the rotor resistance and load torque as well as the above mentioned states required for DTC. The EKF algorithm used in conjunction with the speed sensorless DTC is tested under eleven scenarios comprised of various changes made in the velocity reference beside the load torque and rotor resistance values assigned in the model. With no a priori information in the estimated states and parameters, it has been demonstrated that the EKF estimation and sensorless DTC perform quite well in spite of the uncertainties and variations imposed on the system

Research Update: Spin transfer torques in permalloy on monolayer MoS2

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Wei Zhang

2016-03-01

Full Text Available We observe current induced spin transfer torque resonance in permalloy (Py grown on monolayer MoS2. By passing rf current through the Py/MoS2 bilayer, field-like and damping-like torques are induced which excite the ferromagnetic resonance of Py. The signals are detected via a homodyne voltage from anisotropic magnetoresistance of Py. In comparison to other bilayer systems with strong spin-orbit torques, the monolayer MoS2 cannot provide bulk spin Hall effects and thus indicates the purely interfacial nature of the spin transfer torques. Therefore our results indicate the potential of two-dimensional transition-metal dichalcogenide for the use of interfacial spin-orbitronics applications.

Analysis of the torque capacity of a completely customized lingual appliance of the next generation

Science.gov (United States)

2014-01-01

Introduction In lingual orthodontic therapy, effective torque control of the incisors is crucial due to the biomechanical particularities associated with the point of force application and the tight link between third order deviations and vertical tooth position. Aim The aim of the present in vitro investigation was to analyze the torque capacity of a completely customized lingual appliance of the next generation (WIN) in combination with different finishing archwire dimensions. Methods Using a typodont of the upper arch carrying the WIN appliance, slot filling and undersized individualized β-titanium archwires were engaged. Horizontal forces ranging from 0 to 100 cN were applied at the central incisor by means of spring gauges. The resulting angular deviations were recorded and the corresponding torque moments were calculated. Results For fullsize archwires (0.018”×0.018” β-titanium and 0.018”×0.025” β-titanium), an initial torque play of 0-2° had to be overcome prior to the development of an effective torque moment. Thereafter, a linear correlation between torque angle and torque moment developed for both archwire dimensions with steeper slopes calculated for the specimens with the larger dimension. A torque moment of 2 Nmm required for effective torque correction was noted after a minimum of 2-3° of twist for the 0.018”×0.018” β-titanium wires as compared to 2-4° for the 0.018”×0.025” β-titanium study sample. When undersized archwires were analyzed (0.0175”×0.0175” β-titanium), the measured torque play ranged from 5-7°. After 8-12° of torque angle, the threshold of 2 Nmm was reached. A linear relationship between twist angle and torque moment in which the steepness of the slopes was generally flatter than the ones calculated for the slot filling archwires was noted. Conclusions Given the high precision of the bracket slot-archwire-combination provided with the WIN appliance, an effective torque control can be clinically

A Novel Cogging Torque Simulation Method for Permanent-Magnet Synchronous Machines

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Chun-Yu Hsiao

2011-12-01

Full Text Available Cogging torque exists between rotor mounted permanent magnets and stator teeth due to magnetic attraction and this is an undesired phenomenon which produces output ripple, vibration and noise in machines. The purpose of this paper is to study the existence and effects of cogging torque, and to present a novel, rapid, half magnet pole pair technique for forecasting and evaluating cogging torque. The technique uses the finite element method as well as Matlab research and development oriented software tools to reduce numerous computing jobs and simulation time. An example of a rotor-skewed structure used to reduce cogging torque of permanent magnet synchronous machines is evaluated and compared with a conventional analysis method for the same motor to verify the effectiveness of the proposed approach. The novel method is proved valuable and suitable for large-capacity machine design.