• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 920
  • 810
  • 437
  • 54
  • 40
  • 16
  • 13
  • 9
  • 9
  • 8
  • 6
  • 2
  • 1
  • 1
  • 1
  • Tagged with
  • 2508
  • 1579
  • 1519
  • 1431
  • 1382
  • 1368
  • 1244
  • 1229
  • 1222
  • 445
  • 387
  • 334
  • 157
  • 147
  • 146
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
181

Sittergonomi för kajakpaddlare / Sitting ergonomics for kayak paddlers

Malmstad, Emelie January 2019 (has links)
Kajaker härstammar från inuiterna och är en vattenfarkost som användes för att jaga och fiska. Idag används kajaker även till rekreationspaddling och detta projekt fokuserar på att framställa ett material som ger bättre förståelse för hur det ergonomiska sittandet i en kajak bör se ut. Syftet med projektet är att genomföra det självständigt på ett ingenjörsmässigt sätt och presentera detta skriftligt och muntligt. Projektet genomförs med metoder såsom observationer, intervju, enkäter och faktasökning och mynnar ut i ett informationsunderlag som kan ligga till grund för fortsatt arbete. Informationen presenteras för slutanvändare i form av en broschyr och slutsatsen som dras är att informationen som presenterats för slutanvändarna faller i god jord samt att ett gott ergonomiskt sittande är komplext. / Kayaks originate from the Inuits and is a watercraft that is used for hunting and fishing. Today, kayaks are also used for recreational paddling and this project focuses on producing a material that gives a better understanding of how the ergonomic sitting in a kayak should look. The purpose of the project is to carry it out independently in an engineering way and to present it orally and in writing. The project is carried out using methods such as observations, interviews, questionnaires and searching for facts. It culminates in an information base which can be the basis from which continued work can be carried out. The information has been presented to the end users in the form of a brochure and the conclusion drawn is that the information has been received favourably and that good ergonomic sitting is complex.
182

Atendimento odontológico: eficácia do treinamento e requisitos dos equipamentos para reduzir riscos ergonômicos / Dental care: efficacy of training and equipment requirements to reduce ergonomic risks

Castilho, Ana Virginia Santana Sampaio 20 April 2017 (has links)
Este estudo teve por objetivo verificar a eficácia de um treinamento ergonômico na diminuição de posturas inadequadas adotadas por cirurgiãs-dentistas durante a execução de procedimentos de raspagem periodontal. Sessenta (60) cirurgiãs-dentistas foram alocadas aleatoriamente em dois grupos: o grupo de intervenção - G1, composto por 22 profissionais que receberam instruções e treinamento ergonômico teórico e prático; o grupo controle - G2, composto por 38 profissionais receberam o mesmo treinamento apenas após ao final do estudo. No baseline, utilizou-se um manequim odontológico no qual todas as participantes realizaram procedimentos de raspagem e alisamento dental em 6 faces dentárias, uma em cada sextante: faces vestibulares dos dentes 16, 11, 26 e 31 e faces linguais dos dentes 36 e 46. As observações foram realizadas através de vídeos realizados com 5 câmeras digitais, fixadas num suporte especificamente construído para obtenção de diferentes ângulos de visualização: direita, esquerda, posterior, superior e geral. Realizou-se análise exploratória da distribuição dos dados seguida de análise descritiva e analítica utilizando-se o teste de ANOVA de medidas repetidas com =5%. Foram realizadas 984 análises das quais 720 antes do treinamento e 264 após o treinamento. O treinamento ergonômico possibilitou 63% de redução de prevalência de posturas não recomendadas e houve diferença estatisticamente significante (p<0,00001) entre os grupos controle (inicial e final), intervenção inicial e intervenção final. Concluiu-se que o treinamento ergonômico realizado contribuiu significativamente para diminuir a prevalência de posturas não recomendadas durante a execução de procedimentos básicos periodontais. / This study aimed to assess the efficacy of an ergonomic training in order to decrease the prevalence of not recommended postures assumed by dentists during dental scaling procedures. Sixty (60) female dentists were randomly allocated into two groups: G1- intervention group - composed by 22 dentists who received theoretical and practical ergonomic training; G2 - control group - composed by 38 professionals received the similar training only after the end of the study. In the baseline, it was used a dental manikin in which all participants performed dental scaling on 6 dental surfaces, one in each sextant of the mouth: buccal surfaces of 16, 11, 26 and 31 teeth and lingual faces of 36 and 46 teeth. The observations were made through videos realized with 5 digital cameras, fixed in a support specifically constructed to obtain different viewing angles: right, left, posterior, superior and general. An exploratory analysis of the data distribution followed by descriptive and analytical analysis was performed using the ANOVA test for repeated measures with = 5%. A total of 1440 observations were performed, 720 before and 720 after training. Ergonomic training decrease the prevalence of not recommended postures in 63%. There was a statistically significant difference (p <0.00001) between the control, pre-training intervention and post-training intervention groups. It was concluded that the ergonomic training was effective to decrease the prevalence of not recommended postures during dental scaling procedures.
183

A aplicação do design ergonômico aliado à semiautomatização de funções, como forma de redução de inconvenientes posturais em operadores de uma estação de corte de chapas de madeira /

Martins, Alexander Pereira. January 2008 (has links)
Orientador: Abílio Garcia dos Santos Filho / Banca: João Eduardo Guarnetti dos Santos / Banca: Alberto de Vitta / Banca: Luiz Gonzaga Campos Porto / Banca: César Antunes de Freitas / Resumo: Os trabalhadores em marcenarias, de maneira geral, estão expostos a diversos riscos para a sua integridade física e psicológica. Existe um elevado risco de acidentes, podendo levar ao afastamento do trabalhador por períodos de tempo consideráveis, o que, além de prejudicar o funcionário, implica em prejuízos para as empresas, ocasionados pela indisponibilidade de mão-de-obra qualificada para substituir o acidentado, interferindo, assim, nos prazos de entrega dos produtos e levando conseqüentemente ao afastamento da clientela. O objetivo desta pesquisa é identificar os inconvenientes relacionados às posturas adotadas pelos operadores da atividade da célula de produção responsável pelo corte de painéis de madeira, descrevendo os sintomas músculo-esqueléticos correlacionados, através da aplicação da análise ergonômica, propondo melhorias baseadas nos resultados desta análise, quantificando-as. Como metodologia utilizou-se a aplicação do protocolo avaliação ergonômica, contendo o diagrama de desconforto de CORLLET & BISHOP, a realização da análise ergonômica da atividade e a aplicação do método OWAS. Como resultado dos métodos aplicados verificou-se os pontos necessários para a aplicação da ergonomia corretiva, bem como os resultados oriundos das implantações das melhorias efetuadas / Abstract: The workers in carpentry, in general, are exposed to various risks to their physical and psychological integrity. There is a high risk of accidents, leading to the expulsion of the worker for considerable periods, which, in addition to harming the official, results in losses for businesses, caused by the unavailability of labor-qualified to replace the bumpy, interfering, so in the time of delivery and consequently leading to the expulsion of customers. The objective of this research is identifying the problems related to the posture adopted by operators of the activity of the cell responsible for the production of wood cutting boards, describing the skeletal muscle-related symptoms by applying ergonomic analysis and propose improvements based on the results of this analysis , quantifying them. Methodology was used as the application of ergonomic assessment protocol, containing the diagram of discomfort of CORLLET & BISHOP, the analysis of ergonomic activity and the method Owas. As a result of the methods it was found the points necessary for the implementation of corrective ergonomics as well as the results from the deployment of the improvements made / Mestre
184

Atendimento odontológico: eficácia do treinamento e requisitos dos equipamentos para reduzir riscos ergonômicos / Dental care: efficacy of training and equipment requirements to reduce ergonomic risks

Ana Virginia Santana Sampaio Castilho 20 April 2017 (has links)
Este estudo teve por objetivo verificar a eficácia de um treinamento ergonômico na diminuição de posturas inadequadas adotadas por cirurgiãs-dentistas durante a execução de procedimentos de raspagem periodontal. Sessenta (60) cirurgiãs-dentistas foram alocadas aleatoriamente em dois grupos: o grupo de intervenção - G1, composto por 22 profissionais que receberam instruções e treinamento ergonômico teórico e prático; o grupo controle - G2, composto por 38 profissionais receberam o mesmo treinamento apenas após ao final do estudo. No baseline, utilizou-se um manequim odontológico no qual todas as participantes realizaram procedimentos de raspagem e alisamento dental em 6 faces dentárias, uma em cada sextante: faces vestibulares dos dentes 16, 11, 26 e 31 e faces linguais dos dentes 36 e 46. As observações foram realizadas através de vídeos realizados com 5 câmeras digitais, fixadas num suporte especificamente construído para obtenção de diferentes ângulos de visualização: direita, esquerda, posterior, superior e geral. Realizou-se análise exploratória da distribuição dos dados seguida de análise descritiva e analítica utilizando-se o teste de ANOVA de medidas repetidas com =5%. Foram realizadas 984 análises das quais 720 antes do treinamento e 264 após o treinamento. O treinamento ergonômico possibilitou 63% de redução de prevalência de posturas não recomendadas e houve diferença estatisticamente significante (p<0,00001) entre os grupos controle (inicial e final), intervenção inicial e intervenção final. Concluiu-se que o treinamento ergonômico realizado contribuiu significativamente para diminuir a prevalência de posturas não recomendadas durante a execução de procedimentos básicos periodontais. / This study aimed to assess the efficacy of an ergonomic training in order to decrease the prevalence of not recommended postures assumed by dentists during dental scaling procedures. Sixty (60) female dentists were randomly allocated into two groups: G1- intervention group - composed by 22 dentists who received theoretical and practical ergonomic training; G2 - control group - composed by 38 professionals received the similar training only after the end of the study. In the baseline, it was used a dental manikin in which all participants performed dental scaling on 6 dental surfaces, one in each sextant of the mouth: buccal surfaces of 16, 11, 26 and 31 teeth and lingual faces of 36 and 46 teeth. The observations were made through videos realized with 5 digital cameras, fixed in a support specifically constructed to obtain different viewing angles: right, left, posterior, superior and general. An exploratory analysis of the data distribution followed by descriptive and analytical analysis was performed using the ANOVA test for repeated measures with = 5%. A total of 1440 observations were performed, 720 before and 720 after training. Ergonomic training decrease the prevalence of not recommended postures in 63%. There was a statistically significant difference (p <0.00001) between the control, pre-training intervention and post-training intervention groups. It was concluded that the ergonomic training was effective to decrease the prevalence of not recommended postures during dental scaling procedures.
185

Examining the application of STAMP in the analysis of patient safety incidents

Canham, Aneurin January 2018 (has links)
This thesis examines the application of Systems-Theoretic Accident Model and Processes (STAMP) in healthcare and the analysis of patient safety incidents. Healthcare organisations have a responsibility for the safety of the patients they are treating. This includes the avoidance of unintended or unexpected harm to people during the provision of care. Patient safety incidents, that is adverse events where patients are harmed, are investigated and analysed as accidents are in other safety-critical industries, to gain an understanding of failure and to generate recommendations to prevent similar incidents occurring in the future. However, there is some dissatisfaction with the current quality of incident analysis in healthcare. There is dissatisfaction with the recommendations that are generated from healthcare incident analysis which are felt to produce weak and ineffective remedial actions, often including retraining of individuals and small policy change. Issues with current practice have been linked to the use of Root Cause Analysis (RCA), an analysis method that often results in the understanding of an accident as being the result of a linear chain of events. This type of simple linear approach has been the target of criticism in safety science research and is not felt to be effective in the analysis of incidents in complex systems, such as healthcare. Research in accident analysis methods has developed from a focus on technical failure and individual human actions to consideration of the interactions between people, technology and the organisation. Accident analysis methods have been developed that guide investigations to consideration of the whole system and interactions between system components. These system approaches are judged to be superior to simple linear approaches by the research community, however, they are not currently used in healthcare incident investigation practice. The systems approach of STAMP is felt to be a promising method for the improvement of healthcare incident analysis. STAMP strongly embodies the concepts of systems theory and analyses human decision-making. The application of STAMP in healthcare was investigated through three case studies, which applied STAMP in: 1. The analysis of the large-scale organisational failure at Mid-Staffordshire NHS Trust between 2005-2009. 2. The analysis of a common small-scale hospital-based medication prescription error. 3. The analysis of patient suicide in the community-based services of a Mental Health Trust. The effectiveness of the STAMP applications was evaluated with feedback from healthcare stakeholders on the usability and utility of STAMP and discussion of the STAMP applications against criteria for accident analysis models and methods. Healthcare stakeholders were generally positive about the utility of STAMP, finding it to provide a system view and guide consideration of interactions between system components. They also felt it would help them generate recommendations and were positive about the future application of STAMP in healthcare. However, many felt it to be a complicated method that would need specialist expertise to apply. The STAMP applications demonstrated the ability of STAMP to consider the whole system and guide an analysis to the generation of recommendations for system measures to prevent future incidents. From the findings of the research, recommendations are made to improve STAMP and to assist future applications of STAMP in healthcare. The research also discusses the other factors that influence incident analysis beyond that of the analytical approach used and how these need to be considered to maximise the effectiveness of STAMP.
186

The effects of movement speeds and magnetic disturbance on inertial measurement unit accuracy: the implications of sensor fusion algorithms in occupational ergonomics applications

Chen, Howard 01 May 2017 (has links)
Accurate risk assessment tools and methods are necessary to understand the relationship between occupational exposure to physical risk factors and musculoskeletal disorders. Ergonomists typically consider direct measurement methods to be the most objective and accurate of the available tools. However, direct measurement methods are often not used due to cost, practicality, and worker/workplace disruption. Inertial measurement units (IMUs), a relatively new direct measurement technology used to assess worker kinematics, are attractive to ergonomists due to their small size, low cost, and ability to reliably capture information across full working shifts. IMUs are often touted as a field-capable alternative to optical motion capture systems (OMCs). The error magnitudes of IMUs, however, can vary significantly (>15°) both within and across studies. The overall goals of this thesis were to (i) provide knowledge about the capabilities and limitations of IMUs in order to explain the inconsistencies observed in previous studies that assessed IMU accuracy, and (ii) provide guidance for the ergonomics community to leverage this technology. All three studies in this dissertation systematically evaluated IMUs using a repetitive material transfer task performed by thirteen participants with varying movement speeds (15, 30, 45 cycles/minute) and magnetic disturbance (absent, present). An OMC system was used as the reference device. This first study systematically evaluated the effects of motion speed and magnetic disturbance on the spatial orientation accuracy of an inertial measurement unit (IMU) worn on the hand. Root-mean-square differences (RMSD) exceeded 20° when inclination measurements (pitch and roll) were calculated using the IMU’s accelerometer. A linear Kalman filter and a proprietary, embedded Kalman filter reduced inclination RMSD to < 3° across all movement speeds. The RMSD in the heading direction (i.e., about gravity) increased (from < 5° to 17°) under magnetic disturbance. The linear Kalman filter and the embedded Kalman filter reduced heading RMSD to < 12° and < 7°, respectively. This study indicated that the use of IMUs and Kalman filters can improve inclinometer measurement accuracy. However, magnetic disturbances continue to limit the accuracy of three-dimensional IMU motion capture. The goal of the second study was to understand the capability of IMU inclinometers to improve estimates of angular displacements and velocities of the upper arm. RMSD and peak displacement error exceeded 11° and 28° at the fastest transfer rate (45 cycles/min) when upper arm elevation was calculated using the IMU accelerometer. The implementation of a Kalman filter reduced RMS and peak errors to < 1.5° and < 2.3°, respectively. Similarly, the RMS and peak error for accelerometer-derived velocities exceeded 81°/s and 221.3°/s, respectively, at the fastest transfer rate. The Kalman filter reduced RMS and peak errors to < 9.2°/s and < 25.1°/s, respectively. The third study was conducted to evaluate the relationship between magnetic field strength variation and magnetic heading deviation. In this study, the presence of the metal plate increased magnetic heading deviations from < 12° (90th-10th percentile) to approximately 30°. As expected, the magnetic field strength standard deviation increased from 1.0uT to 2.4uT. While this relationship may differ across other sources of magnetic disturbance, the results reinforce the notion that local magnetic field disturbances should be minimized when using IMUs for human motion capture. Overall, the findings from this thesis contribute to the ergonomics community’s understanding of the current capabilities and limitations of IMUs. These studies suggest that while the touted capabilities of the IMUs (full-body motion capture in workplace settings) may be unattainable based on current sensor technology, these sensors are still significantly more accurate than the accelerometer-based inclinometers commonly used by ergonomists to measure motions of the upper arms.
187

The Human Factors Design of a Wearable Balance Belt

Zachrisson, Therese January 2007 (has links)
<p>Being able to keep your balance is something most of us take for granted. People with inner ear problems due to an accident or surgery or other dizziness have to live with this problem on a chronic basis. A balance prosthesis, worn around the torso, giving feedback about their upright position via tactile vibrators has been shown to help these people keep their balance.</p><p>The goal and purpose for this thesis has been to conduct research on how to improve the existing balance prosthesis and adapt it to fit the user. The research has been conducted with the focus on human factors, meaning with the users’ experience as the premier aspect.</p><p>To be able to reach a good solution with a prototype that would be an improvement compared to the existing device, a vest, several stages have been passed. At first twelve criteria were set up to establish human factors and hedonomic requirements. To fulfill these requirements, surveys with users were conducted. An extensive phase of prototyping and material research informed the design of a final concept.</p><p>The final concept was a prototype balance belt that contains six vibrators, called tactors, and models of the other electronic components. The belt has an elastic band as a base and then a black spandex fabric that covers all components. A Velcro band and a buckle are used to open and close the belt. Finally the belt has a beige spandex cover that can be pulled on and off. This cover makes the belt easy to keep clean because the cover can be washed.</p><p>The prototype is made in three different sizes so it can fit most people in the US population.</p><p>In the near future it will be important to make an evaluation of the balance belt with users. It needs to be tested if the vibrators are possible to feel and how it feels to wear the belt for a longer time. An aid to help pulling the cover onto the belt also has to be developed because putting on the cover is a bit difficult right now.</p>
188

Using Tentacles in Planning and Scheduling Work : Activities, Roles and Contributions

Berglund, Martina January 2009 (has links)
Handling production scheduling is increasingly difficult for manyenterprises, and human involvement is necessary. The overall objective ofthis research was to gain further understanding of planners’ and schedulers’work within the manufacturing industry, to elucidate how their worksituation is formed, and to explain their significance to other employees’work and company activities. Scheduling work was studied in fourcompanies in the Swedish woodworking industry; a sawmill, a parquet floormanufacturer, a furniture manufacturer and a house manufacturer. Themethod used was activity analysis which is based on the analysis of workactivities in real work situations. Data collection included 20 days’observations and 65 interviews. Cross-case analysis with British cases onplanning work was also included.The findings revealed that the schedulers’ tasks lead to many activities. Twothirds of these are what can be expected. The remaining third constitutesactivities that depend on the schedulers’ individual attributes and the contextin which they work. The schedulers serve as problem solvers in a number ofdomains and constitute efficient information nodes, making them animportant service function. Furthermore, they have an alignment rolebetween different organizational groups. This role is specifically remarkablein dealing with production enquiries that must be aligned with productioncapability. Here, both planners and schedulers play an essential role inlinking the manufacturing and the commercial sides and their differentfunctional logics.Planners and schedulers in daily work exert strong influence on others. Theydo not hold legitimate power. Instead their influence emanates mainly fromaccess to and control of information and their ability to apply expertise tointerpret this information and examine the impact of decisions made acrossdifferent areas of the business. Personal power related to social skills is alsosignificant.Furthermore, they facilitate others’ work in continuous personalinteractions, serving the technical scheduling software system, and aligningdifferent organizational functions. In combination with expert knowledgeand developed social skills, they significantly contribute to quality operationsperformance. Finally, the schedulers influence the decision latitude of otheremployees and may indirectly promote job satisfaction, thus contributing todeveloping appropriate working conditions for others in the company. / QC 20100624
189

Design of Natural Warning Sounds in Human-Machine Systems

Ulfvengren, Pernilla January 2003 (has links)
The goal of this research is increased safety in aviation. Aviation is a highly automated and complex, as well as, safety critical human-machine system. The pilot communicates with the system via a human-machine interface in cockpit. In an alerting situation this interface is in part an auditory alerting system. Human errors are often consequences of actions brought about by poor design. Pilots complain that they may be both disturbed and annoyed of alerts, which may affect performance, especially in non-normal situations when the mental workload is high. This research is based on theories in ergonomics and cognitive engineering with the assumption that improved human performance within a system increase safety. Cognitive engineering is a design philosophy for reducing the effort required by cognitive functions by changing the technical interface, which may lead to improved performance. Knowledge of human abilities and limitations and multidisciplinary interrelated theories between humans, sounds and warnings are used. Several methods are involved in this research, such as literature studies, field studies, controlled experiments and simulations with pilots. This research defines design requirements for sounds appropriate in auditory alerts as Natural Warning Sounds. For example, they have a natural meaning within the user’s context, are compatible with the auditory information process, are pleasant to listen to (not annoying), are easy to learn and are clearly audible. A design process for auditory alerting systems is suggested. It includes methods of associability and sound imagery, which develop Natural Warning Sounds, and combines these with an appropriate presentation format. Associability is introduced and represents the required effort to associate sounds to their assigned alert function meaning. An associable sound requires less effort and fewer cognitive resources. Soundimagary is used to develop sound images. A sound image is a sound, which by its acoustics characteristics has a particular meaning to someone without prior training in a certain context. Simulations of presentation formats resulted in recommendations for cancellation capabilities and avoiding continuously repeated alerts. This research brings related theories closer to practice and demonstrates general methods that will allow designers, together with the users of the system, to apply them in their own system. / QC 20100910
190

The Human Factors Design of a Wearable Balance Belt

Zachrisson, Therese January 2007 (has links)
Being able to keep your balance is something most of us take for granted. People with inner ear problems due to an accident or surgery or other dizziness have to live with this problem on a chronic basis. A balance prosthesis, worn around the torso, giving feedback about their upright position via tactile vibrators has been shown to help these people keep their balance. The goal and purpose for this thesis has been to conduct research on how to improve the existing balance prosthesis and adapt it to fit the user. The research has been conducted with the focus on human factors, meaning with the users’ experience as the premier aspect. To be able to reach a good solution with a prototype that would be an improvement compared to the existing device, a vest, several stages have been passed. At first twelve criteria were set up to establish human factors and hedonomic requirements. To fulfill these requirements, surveys with users were conducted. An extensive phase of prototyping and material research informed the design of a final concept. The final concept was a prototype balance belt that contains six vibrators, called tactors, and models of the other electronic components. The belt has an elastic band as a base and then a black spandex fabric that covers all components. A Velcro band and a buckle are used to open and close the belt. Finally the belt has a beige spandex cover that can be pulled on and off. This cover makes the belt easy to keep clean because the cover can be washed. The prototype is made in three different sizes so it can fit most people in the US population. In the near future it will be important to make an evaluation of the balance belt with users. It needs to be tested if the vibrators are possible to feel and how it feels to wear the belt for a longer time. An aid to help pulling the cover onto the belt also has to be developed because putting on the cover is a bit difficult right now.

Page generated in 0.0912 seconds