Orientador: Kleber Pereira Lanças / Banca: João Eduardo Guarnetti dos Santos / Banca: João Alberto Borges de Araújo / Banca: Alberto Kazushi Nagaoka / Banca: Saulo Philipe Sebastiao Guerra / Resumo: Este trabalho teve como objetivo determinar e comparar os níveis de vibração mecânica incidente sobre o corpo inteiro do operador de um trator agrícola ensaiado em pistas padronizadas e de solo. O experimento foi conduzido em pistas de ensaios pertencentes ao Núcleo de Ensaio de Máquinas e Pneus Agroflorestais (NEMPA) do Departamento de Engenharia Rural da Faculdade de Ciências Agronômicas da Universidade Estadual Paulista "Júlio de Mesquita Filho", em Botucatu, São Paulo. Os dados foram coletados em pista de ensaio de vibração padronizada, pista padronizada de concreto e pista de solo durante operação de roçada, escarificação, aração e gradagem. Foram adotadas quatro velocidades de deslocamento e duas combinações de pressões de inflação dos pneus. A aquisição de dados foi feita com um acelerômetro de três eixos fixado no assento do operador. Os parâmetros avaliados foram os valores de soma dos eixos para aceleração média, valor da dose de vibração (nível de alerta) e a projeção de dose para 8 horas de trabalho. Os dados obtidos foram submetidos ao teste de Tukey (p≤0,05). A condição superficial foi determinante para definir o comportamento dos dados e ocasionar os cenários de insalubridade, principalmente na pista padronizada para ensaio de vibração e na execução da gradagem em solo arado. Foram encontradas correlações entre os valores de dose de vibração resultante da pista padronizada de vibração e os obtidos nas operações de aração e de gradagem. Nas condições operacionai... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The objective of this study was to determine and compare the levels of mechanical vibration incident on the whole body of the agricultural tractor operator tested on standardized tracks and soil. The experiment was carried out in the tests tracks belonging to the Núcleo de Ensaio de Máquinas e Pneus Agroflorestáis (NEMPA) of the Departamento de Engenharia Rural of the Faculdade de Ciências Agronômicas of the Universidade Estadual Paulista "Júlio de Mesquita Filho", in Botucatu, São Paulo. The data were collected in standardized vibration test track, standard concrete track and soil track during mowing, scarification, plowing and harrowing. Four shift speeds and two combinations of tire inflation pressures were adopted. Data acquisition was done with a three-axis accelerometer fixed to the operator's seat. The parameters evaluated were the sum values of the axes for mean acceleration, the vibration dose value (alert level) and the dose projection for 8 working hours. The data were submitted to the Tukey test (p≤0.05). The superficial condition was determinant to define the behavior of the data and to cause the scenarios of insalubrity, mainly in the standardized track for vibration test and in the execution of the harrowing in plowed soil. Correlations were found between the vibration dose value of the standardized vibration track and those obtained in the plowing and harvesting operations. In the operating conditions tested, unhealthy conditions were found in the execution of plowing and harvesting. The standardized vibration test track provided a condition of greater severity than those encountered in mechanized operations conducted on the soil track. The concrete track was not representative of any of the operations conducted on the soil track. The speed was more important than the internal tire pressure to determine the mean acceleration values, vibration dose value and accumulated ... / Doutor

Thesis (M.S.) -- Mississippi State University. Department of Industrial and Systems Engineering. / Title from title screen. Includes bibliographical references.

On-the-go users' interaction with mobile devices often requires high visual attention that can overtax limited human resources. For example, while attending information displayed on a mobile device, on-the-go users who are driving a car or walking in the street can easily fail to see a dangerous situation. This dissertation explores the benefits of wearable tactile displays (WTDs) to support eyes-free interaction for on-the-go users. The design and implementation of the WTDs are motivated by two principles in mobile user interaction that have been proven both commercially and academically: wristwatch interfaces that reduce the time for device acquisition and tactile interfaces that eliminate the need for visual attention. In this dissertation, I present three phases of design iteration on WTDs to provide the design rationale and challenges. The result of the iterative design is evaluated through in-depth formal investigations with novice users in two experiments: user perception of the tactile stimuli and information throughput in association with multiple tactile parameters, and perception of the tactile stimuli and information throughput when the user is visually distracted. The first experiment explores general human capabilities in perceiving tactile stimuli on the wrist. It reveals that subjects could discriminate 24 tactile patterns with 98% accuracy after 40 minutes of training. Of the four parameters (intensity, starting point, rhythm, direction) that were configured to design the 24 patterns, intensity was the most difficult parameter to distinguish, and temporal variation was the easiest. The second experiment explores users' abilities to perceive incoming alerts from two mobile devices (WTD and mobile phone) with and without visual distraction. The second experiment reveals that when the user was distracted visually, reaction time to perceive the incoming alerts became slower with the mobile phone alert but not with the WTD.

Dissertation (Ph.D.) - Simon Fraser University, 2006. / Theses (School of Kinesiology) / Simon Fraser University. Includes bibliographical references. Also issued in digital format and available on the World Wide Web.

Thesis (Ph. D.)--Mississippi State University. Department of Industrial Engineering. / Title from title screen. Includes bibliographical references.

Thesis (M. Arch.)--University of Hong Kong, 1995. / Includes special study report entitled: Movement analysis with respect to site circulation & interior circulation. Includes bibliographical references.

This thesis examines human performance under sub-optimal working conditions during work with complex and highly-automated process control systems. The operational context focuses on applications in extended spaceflight but the generic approach allows for generalisations beyond this target work environment The methodological approach is based on the use of a computerised multiple-task environment to carry out generic simulations of real work environments (micro-worlds) with a high level of ecological validity. For that purpose, a PC-based task. environment was developed to simulate the operation of a life support system in a spacecraft. This task environment has been used in lab-based experiments with trained participants from the student population and with real space crews during large-scale mission simulations. A series of six experiments was carried out (3lab and 3 field studies) to investigate the impact of different configurations of sub-optimal working conditions and unfavourable operator states, using the following independent variables: sleep deprivation, dialogue control, social isolation and confinement, training, noise, extended lay-off period and different types of system faults (corresponding to variations in workload). The task environment comprised up to five tasks, allowing for the observation of differential effects of the independent variables on different levels of cognitive activity. Dependent variables included primary task performance, secondary task performance, system control behaviour, information sampling behaviour, and subjective state measures. The findings suggested that primary performance was rarely affected, whereas certain secondary task measures and, notably, information sampling strategies appeared to be good indicators of changes in demand under the unfavourable conditions. The isolation and confinement experiments revealed no serious breakdown of performance among the crew but some indications of strain were observed. The use of two different training approaches displayed a very complex picture, with no method showing clear superiority over the other concerning performance, though there were differences in knowledge structure and system management behaviour. An important implication of the experimental work is that a broad methodological approach is needed in order to investigate the complex adjustment patterns displayed by individuals during the management of task demands under unfavourable conditions.

Many organizations are using ergonomic principles and its applications to improve and optimize the current levels of productivity, safety and health. This can be achieved by carefully examining the current management and work practices with the view of finding alternative ways to perform these tasks. In view of the above this research examines the current management and work practices of three small manufacturing engineers, with the purpose of providing inputs, to improve their current status through the application of ergonomic principles. The study is divided into three parts. The first part focuses on the review of current literature on ergonomics and specifically discusses issues such as anthropometry, cumulative trauma disorders, manual material handling, and ergonomic based management systems. The second part focuses on an assessment and identification of existing problems and areas of weaknesses in the workplace. This was accomplished through in depth interviews, observation and questionnaires. The final part presents the research findings followed by the discussion and proposed recommendations. The study has revealed that there is a fundamental lack of knowledge of ergonomics and its relationship to productivity, safety and health. Currently most work practices are guided by what has been learnt and internalized over the years. The researcher proposes that in order to successfully implement an ergonomics programme, ergonomic awareness, training and education, self help training, management commitment and work force participation are essential. / Thesis (MBA)-University of KwaZulu-Natal, Durban, 2004.

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