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A study of the relative efficiency of a symmetrical versus a non symmetrical hand motion path in the performance of short run industrial operationsEdwards, John Cortner January 1946 (has links)
With present wage levels already high, and with organized labor demanding still higher wages for the future, it is necessary for management to secure higher productivity from labor in the future than has been secured in the past. In some cases organized labor has demanded that future wage increases be granted with the understanding that such increases will not be followed by compensating price increases. Wage increases without compensating prices increases can be satisfactorily granted only if the wage increases are accompanied by increased labor productivity. At the present time, such increased productivity cannot be obtained by speeding up the operator to an unreasonable pace. Labor will not tolerate such practices. The increased labor productivity necessary to compensate for wage increases must, therefore, be obtained by the use of more efficient production methods. In some cases, increased productivity is secured by the installation of more efficient machinery and equipment. In other cases, particularly with assembly operations, rearrangement of the stock bins, the installation of simple jigs and fixtures, and the revision of work methods to eliminate unnecessary motions and to increase the efficiency of performing the remaining motions may cause considerable increases in labor productivity without unreasonable speed up. This latter method of increasing efficiency is known by various names, some of the more common of which are motion study, methods engineering, and work simplification.
The average person usually visualizes modern production as performed almost exclusively by large numbers of workers who constantly repeat the same operation for long periods of time. Doctor Ralph M. Barnes, on page 349 of Motion and Time Study (1), points out that such long-run production is not the typical situation even in larger plants. On the other hand, Doctor Barnes states that most operators work on relatively short-run production with frequent work changes. Any method of increasing the productivity of short-run production would, therefore, be applicable to a wide range of industrial effort.
Motion study literature recognizes the fact that, other things being equal, a person tends to perform an operation faster if the work is arranged so that it can be performed by a symmetrical motion path rather than if it is performed by a nonsymmetrical motion path. Small assembly work is usually performed symmetrically by the expedient of arranging the workplace so that each hand builds a complete assembly simultaneously with the other hand.
A hand motion path is said to be symmetrical when it meets two requirements. First, at any point in the cycle the right and left hands are equal distances to the right and left respectively of the center line of the body; to fulfill this requirement, components of motion to the right and left of the center line of the body must be performed by the hands moving simultaneously, in opposite directions, and for equal distances. Secondly, at any point in the cycle the right and left hands are equal distances in front of the body; to fulfill this requirement, components of motion toward or away from the body must be performed by the hands moving simultaneously, in the same direction, and for equal distances.
Several years ago, while the author was employed as a motion study operations which led him to believe that considerably larger time savings could be made by the application of symmetrical motion paths to short-run production, than could be made on long-run production where the worker changed operations infrequently. It appeared that less practice was required to attain a given level of skill if the motion path were symmetrical than if it were nonsymmetrical. Since, as has already been pointed out, short-run production represents a very large proportion of all industrial effort, it appeared profitable to make a study to determine if the application of symmetrical motion paths would actually yield greater savings on short-run production than on long-run production; any methods producing time savings on short-run production would have a wide field of possible applications.
It was the purpose of this study to determine if the impressions mentioned in the preceding paragraph could or could not be verified. An operation was arranged so that it could be performed by either a symmetrical or a nonsymmetrical motion path. Several operators performed short 25-cycle runs of the operation by one motion path and then shifted to the alternate motion path at the end of each 25-cycle run. This procedure was continued until 29 runs by each motion path had been completed by each operator. Such a procedure produced the effect of the operators working on short-term production with frequent changes of operation. All operating times were recorded. A comparison of the time records for the two motion paths gave an index of their relative efficiency. Such comparison did indicate that greater time savings could be expected from the application of symmetrical motion paths to short-run production than by application to long-run production. / Master of Science
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An investigation of the effect of varying loads on the time required for cranking motionsThomas, Jack Valentine 26 April 2010 (has links)
Master of Science
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DEVELOPING A TIME AND MOTION STUDY FOR A LEAN HEALTHCARE ENVIRONMENTPatton, Michael Winston, Jr. 01 January 2011 (has links)
This thesis outlines the development of a standard methodology for performing a time and motion study in a lean healthcare environment. Time and motion studies have been used in healthcare environments in the past, however they have nearly all been exclusive to a particular healthcare enterprise. To develop the time and motion study methodology, a study was designed to examine how resident doctors spend their time. This study was performed in response to coming changes in the work hours for all residents. Once the methodology was developed, trial observations were conducted. The data from these observations was analyzed to determine the effectiveness of both the time and motion study methodology and its usefulness for process improvement activities.
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Effect of a Concentrated In-service Elementary Teacher Force and Motion WorkshopNelson, David January 2006 (has links) (PDF)
No description available.
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Process Improvement of Door Manufacturing through Time Study and Simulation using Lean ConceptsChen, Chen 03 May 2019 (has links)
This project investigated the effects of process capability, line station operation efficiency, and line balance on the product throughput of a wooden door manufacturing process using time-and-motion study and simulation methods. The problem-solving approach DMAIC was used to identify root causes to the problems and implemented the process improvements for the production line efficiency and throughput based on lean manufacturing concepts. The investigation results indicated that the main operation of the wooden door manufacturing process was based on manual and semi-automatic operations. The process capability of whole operation before implementing process improvements was around 600 doors monthly. The coefficient of variation of process time for manual operation ranged from 12% to 23%. The semi-automatic operation ranged from 2% to 20%. The average station efficiency and throughput was 31% and 20 doors per day respectively. After implementing the removal of obvious motion waste, the processing time of the whole process reduced 22.9%. The reduced process time variation for manual operation ranged from 9% to 14%, and the semi-automatic operations ranged from 3% to 7%. The final product output had a 200% increase and the total process efficiency had 100% improvement after implementing the improved process flow design. Meanwhile, the average station efficiency and output increased to 61% and 65 doors per day, respectively.
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A survey on common misconceptions of force and motion among secondary science students in Hong Kong.January 1989 (has links)
by Au Yeung Po See. / Title also in Chinese. / Thesis (M.A.Ed.)--Chinese University of Hong Kong, 1989. / Bibliography: p. 61-72.
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Distribuição do tempo das enfermeiras: identificação e análise em unidade médico-cirúrgica / Nursery time distribution: identification and analysis in a medical-surgical unitBordin, Luiz Carlos 11 June 2008 (has links)
Diante do impacto da distribuição do tempo de trabalho da profissional enfermeira na determinação de parâmetros adequados para a operacionalização do processo de dimensionar pessoal de enfermagem, este estudo teve por objetivo identificar e analisar a distribuição do tempo de trabalho das enfermeiras em uma unidade de internação médico-cirúrgica. Trata-se de uma pesquisa de campo, prospectiva, de abordagem quantitativa, do tipo exploratório-descritiva, realizada em um Hospital geral, privado, de grande porte da cidade de São Paulo. Para a consecução dos objetivos da pesquisa considerou-se, como população estatística, as atividades de enfermagem realizadas pelas enfermeiras durante os turnos de trabalho. O tamanho da amostra e o período amostral foram estabelecidos a partir da determinação de critérios relacionados à probabilidade mínima de ocorrência das atividades realizadas pelas enfermeiras, bem como do número de enfermeiras por turno e do intervalo estipulado para a realização das observações das atividades executadas pelas enfermeiras. A identificação das atividades de enfermagem realizadas pelas enfermeiras ocorreu mediante solicitação de que cada enfermeira relacionasse, por escrito, as atividades executadas no cotidiano de trabalho da Unidade, que foram, posteriormente, categorizadas de acordo com um sistema padronizado de linguagem (NIC) e classificadas em intervenções de cuidado direto, intervenções de cuidado indireto, atividades associadas e de tempo pessoal. Os dados foram coletados no período de 15 a 19 de outubro de 2007, por quatro observadoras de campo, contratadas e treinadas especificamente, para a realização deste procedimento. Obteve-se 1032 amostras das atividades realizadas pelas enfermeiras, verificando-se que as intervenções e atividades de enfermagem que mais utilizaram o tempo de trabalho das enfermeiras foram Documentação (18,4%), Tempo Pessoal (17,8%), Supervisão (11,4%), Atividades Associadas (9,7%), Delegação (9,3%), Passagem do Plantão (4,8%), Apoio ao Médico (3,9%) e Cuidados na Admissão (3,1%). Observou-se que 50% do tempo das enfermeiras foram dedicados às intervenções de cuidado indireto, 22% às intervenções de cuidado direto de enfermagem, 18% às atividades de tempo pessoal e 10% às atividades associadas. Estes dados corroboram a indicação de pesquisadores que apontam a necessidade de serem considerados o tempo pessoal dos trabalhadores de enfermagem e a realização das atividades associadas nos métodos de dimensionamento de pessoal preconizados pelos órgãos oficiais. Com este estudo evidenciam-se perspectivas para a realização de novas investigações no sentido de contribuir para o aperfeiçoamento dos parâmetros relacionados à temática dimensionamento de pessoal de enfermagem em instituições hospitalares / The aim of this study was to identify and to analyze the work time distribution of nurses in a medical-surgical unit, considering the impact of the work time distribution of nurses to determine the adequate parameters for the process to measure nursery personnel .This is a prospective, quantitative, exploratory-descriptive type field research, conducted in a large, private, general hospital in the city of São Paulo. The activities performed by nursery personnel during work shifts were considered as statistical population to reach our objectives. Sample size and period were established after determining the criteria related to the minimum occurrence possibility of activities performed by the nurses, as well as the number of nursery personnel per shift and the specific interval to perform activities by the nurses. The identification of the nursing activities occurred by asking each nurse to write a report mentioning their daily activities at the Unit, which were later categorized in accordance with the standard language system (NIC) and classified as direct care and indirect care interventions, associated activities and personal time. Data were collected during the period from the 15th to the 19th of October, 2007, by four field observers, specifically hired and trained for this procedure. 1032 samples were obtained from the nurses\' activities. The nursing activities and interventions that most used work time of the nurses were: Documents (18,4%), Personal Time (17,8%), Supervision (11,4%), Associated Activities (9,7%), Assignment (9,3%), Shift Change (4,8%), Doctor\'s Support (3,9%) and Admission Care (3,1%). It was observed that 50% of the nurses\' time was dedicated to indirect care interventions, 22% to direct care nursing interventions, 18% to personal time activities and 10% to related activities. These data corroborated with the researcher\'s indication that showed the need to consider personal time of the nurse\'s work and the performance of associated activities within the methods of personnel measurement recommended by official institutions. New investigations are needed to contribute to the improvement of the parameters related to the nursing personnel measurement in hospital institutions
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Contribution à l'étude tridimensionnelle in vitro et in vivo de la cinématique et des bras de levier musculaires du rachis cervical supérieur: modélisation musculo-squelettique par infographie / In vitro and in vivo kinematics analysis and muscle moment arms comptutation of the suboccipital spine: musculoskeletal modeling and motion representationDugailly, Pierre-Michel 08 December 2011 (has links)
Ce travail de thèse porte sur l’étude de la cinématique 3D du rachis cervical supérieur ainsi que<p>sur l’analyse des bras de levier des muscles sous-occipitaux postérieurs, par le développement<p>de différentes méthodes contribuant à la modélisation anatomique du mouvement.<p>La première partie de ce travail s’oriente vers l’étude des mouvements de flexion extension, de<p>rotation axiale et de flexion latérale ainsi que des axes qui y sont rapportés. Pour ce faire, deux<p>protocoles ont été développés sur préparations anatomiques, l’un visant à analyser les<p>mouvements discrets à partir de différentes attitudes du rachis cervical supérieur et l’autre<p>s’intéressant aux mouvements instantanés. Ceux-ci ont permis de mettre en évidence une<p>orientation et une position de l’axe hélicoïdal dépendantes du mouvement, du segment étudié<p>et de sa position spatiale.<p>En deuxième intention, nous nous sommes intéressés aux propriétés biomécaniques musculaires<p>de cette région, et en particulier à l’étude des bras de levier. Deux méthodes de calcul<p>distinctes ont été utilisées, montrant chacune des résultats différents d’un point de vue<p>quantitatif mais relativement similaires au niveau qualitatif.<p>Pour terminer, nous avons exploité ces méthodes afin d’apprécier leur faisabilité dans le cadre<p>d’une évaluation fonctionnelle in vivo. Il en ressort une concordance de résultats cinématiques<p>par rapport aux études susmentionnées, permettant d’entrevoir des perspectives cliniques<p>encourageantes.<p>Par ailleurs, la modélisation musculo-squelettique 3D pourrait également contribuer à la<p>compréhension du dysfonctionnement cinématique du rachis cervical supérieur./ <p><p>This thesis concerns 3D kinematics analysis of the upper cervical spine (UCS) and computation of the posterior suboccipital muscle moment arms as well the development of different methods contributing to anatomical modeling and motion representation. The first part of this work is focused on the kinematics of flexion extension, axial rotation and lateral bending of the UCS. Two protocols were developed and applied in anatomical specimens, one to analyze discrete movements in different attitudes of upper cervical spine and the second concerned instantaneous motions. In addition to usual range of motion data, orientation and position of helical axes was computed for each motion type and UCS joint segment.<p>In the second part, we were interested in posterior suboccipital muscle biomechanical properties, particularly in the study of moment arms. Two different calculation methods were used, each showing different results from a quantitative point of view but quite similar in quality. Finally, we used these methods to assess their feasibility for in vivo functional assessment. The latter showed a concordance of kinematic results compared to the above studies, offering insight and clinical perspectives. In addition, musculoskeletal modelling 3D could also contribute to understanding of the kinematic features of upper cervical spine disorders.<p> / Doctorat en Sciences biomédicales et pharmaceutiques / info:eu-repo/semantics/nonPublished
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Distribuição do tempo das enfermeiras: identificação e análise em unidade médico-cirúrgica / Nursery time distribution: identification and analysis in a medical-surgical unitLuiz Carlos Bordin 11 June 2008 (has links)
Diante do impacto da distribuição do tempo de trabalho da profissional enfermeira na determinação de parâmetros adequados para a operacionalização do processo de dimensionar pessoal de enfermagem, este estudo teve por objetivo identificar e analisar a distribuição do tempo de trabalho das enfermeiras em uma unidade de internação médico-cirúrgica. Trata-se de uma pesquisa de campo, prospectiva, de abordagem quantitativa, do tipo exploratório-descritiva, realizada em um Hospital geral, privado, de grande porte da cidade de São Paulo. Para a consecução dos objetivos da pesquisa considerou-se, como população estatística, as atividades de enfermagem realizadas pelas enfermeiras durante os turnos de trabalho. O tamanho da amostra e o período amostral foram estabelecidos a partir da determinação de critérios relacionados à probabilidade mínima de ocorrência das atividades realizadas pelas enfermeiras, bem como do número de enfermeiras por turno e do intervalo estipulado para a realização das observações das atividades executadas pelas enfermeiras. A identificação das atividades de enfermagem realizadas pelas enfermeiras ocorreu mediante solicitação de que cada enfermeira relacionasse, por escrito, as atividades executadas no cotidiano de trabalho da Unidade, que foram, posteriormente, categorizadas de acordo com um sistema padronizado de linguagem (NIC) e classificadas em intervenções de cuidado direto, intervenções de cuidado indireto, atividades associadas e de tempo pessoal. Os dados foram coletados no período de 15 a 19 de outubro de 2007, por quatro observadoras de campo, contratadas e treinadas especificamente, para a realização deste procedimento. Obteve-se 1032 amostras das atividades realizadas pelas enfermeiras, verificando-se que as intervenções e atividades de enfermagem que mais utilizaram o tempo de trabalho das enfermeiras foram Documentação (18,4%), Tempo Pessoal (17,8%), Supervisão (11,4%), Atividades Associadas (9,7%), Delegação (9,3%), Passagem do Plantão (4,8%), Apoio ao Médico (3,9%) e Cuidados na Admissão (3,1%). Observou-se que 50% do tempo das enfermeiras foram dedicados às intervenções de cuidado indireto, 22% às intervenções de cuidado direto de enfermagem, 18% às atividades de tempo pessoal e 10% às atividades associadas. Estes dados corroboram a indicação de pesquisadores que apontam a necessidade de serem considerados o tempo pessoal dos trabalhadores de enfermagem e a realização das atividades associadas nos métodos de dimensionamento de pessoal preconizados pelos órgãos oficiais. Com este estudo evidenciam-se perspectivas para a realização de novas investigações no sentido de contribuir para o aperfeiçoamento dos parâmetros relacionados à temática dimensionamento de pessoal de enfermagem em instituições hospitalares / The aim of this study was to identify and to analyze the work time distribution of nurses in a medical-surgical unit, considering the impact of the work time distribution of nurses to determine the adequate parameters for the process to measure nursery personnel .This is a prospective, quantitative, exploratory-descriptive type field research, conducted in a large, private, general hospital in the city of São Paulo. The activities performed by nursery personnel during work shifts were considered as statistical population to reach our objectives. Sample size and period were established after determining the criteria related to the minimum occurrence possibility of activities performed by the nurses, as well as the number of nursery personnel per shift and the specific interval to perform activities by the nurses. The identification of the nursing activities occurred by asking each nurse to write a report mentioning their daily activities at the Unit, which were later categorized in accordance with the standard language system (NIC) and classified as direct care and indirect care interventions, associated activities and personal time. Data were collected during the period from the 15th to the 19th of October, 2007, by four field observers, specifically hired and trained for this procedure. 1032 samples were obtained from the nurses\' activities. The nursing activities and interventions that most used work time of the nurses were: Documents (18,4%), Personal Time (17,8%), Supervision (11,4%), Associated Activities (9,7%), Assignment (9,3%), Shift Change (4,8%), Doctor\'s Support (3,9%) and Admission Care (3,1%). It was observed that 50% of the nurses\' time was dedicated to indirect care interventions, 22% to direct care nursing interventions, 18% to personal time activities and 10% to related activities. These data corroborated with the researcher\'s indication that showed the need to consider personal time of the nurse\'s work and the performance of associated activities within the methods of personnel measurement recommended by official institutions. New investigations are needed to contribute to the improvement of the parameters related to the nursing personnel measurement in hospital institutions
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Mechanical System Design of a Haptic Cobot ExoskeletonLaFay, Eric Bryan 24 August 2007 (has links)
No description available.
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