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  • 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.
151

How to use a user : Important aspects of user involvement within ergonomics-related product development

Petrén, Nina, Söderquist, Hanna January 2015 (has links)
Systematically involving users in product development is considered as a successful strategy and makes companies more competitive. User involvement in various organizational settings, activities or situations can clearly contribute to product development. In order to understand how, dimensions of user involvement and interdependencies between them are in this report identified and investigated. The result shows that the four dimensions of When, Who, Where and How are the most important to consider when involving users. These can each be broken down into a number of aspects that should be used when assessing and comparing sources of user knowledge. With the framework presented in the report, sources of user knowledge can be linked to one or more user involvement situations, meaning when and how to utilize it. The other way around, if a development process enters a certain phase, these aspects could be used to state what requirements there are regarding the users and the context. A source that is to be utilized must hence fulfill these requirements if the user involvement should be appropriate and effective. Additionally, the empirical study showed that apart from the theoretical aspects above, there could be several more aspects to consider when involving users. These are company-specific and should be identified for each company that wants to implicate user involvement. This study shows that there are clearly interdependencies between the dimensions of user involvement. These interdependencies make many types of user knowledge sources suitable only for the Strategy and idea generation phase, and it’s evidently difficult to identify, locate and utilize sources that fulfill the requirements of user involvement in the later phases of a product development process. The empirics showed that the interdependencies between the aspects of user involvement are neglected in many cases, resulting in user knowledge sources being utilized in a phase where they’re not appropriate to be utilized. To overcome this, many different sources are required in order to achieve proper user involvement, and combinations of various sources should be involved to “cover” the whole development process. The models presented and implemented in this study could be utilized in order to pinpoint aspects of existing sources of user knowledge. It could also be employed in order to investigate requirements on a source of user knowledge in relation to a current development phase of a project. This way, companies could specify which type of sources that are missing in their product development process and in a more efficient way work towards filling those gaps.
152

Utvecklingssamtal ur ett kommunikationsperspektiv / Staff Appraisal From a Perspective of Communication

Söderberg, Sophia, Välitalo, Malin January 2008 (has links)
Genom vår utbildnings gång har vi blivit allt mer intresserade av samspelet mellan chef och medarbetare eftersom vi ser att det är en förutsättning att detta fungerar för att få en vinnande organisation. Trots att vi går mot allt fler decentraliserade organisationer och de båda parterna oftast arbetar närmare varandra än tidigare verkar utvecklingssamtal vara ett av de få tillfällen där medarbetare och chef har en enskild dialog med varandra. Därför har vi i denna uppsats valt att göra en kvalitativ undersökning om hur dessa utvecklingssamtal verkligen fungerar. Då vi under vår utbildnings gång även kommit till insikt med att god kommunikation är en förutsättning för att kunna skapa en relation, har vi valt att även se hur denna fungerar parterna emellan och om det är den som är orsak till eventuella brister i utvecklingssamtalen. Med detta som grund valde vi att i vår teoridel skriva om både utvecklingssamtal och kommunikation samt hur dessa samspelar för att få en än bättre förståelse för dessa områden. Vi kontaktade Niklas Andersson, personalsekreterare på Karlstads Kommun, som hjälpte oss med urval och kontakter. Detta resulterade i två enheter inom vård- och omsorgsförvaltningen som undersökningsobjekt, vilket benades ut i sammanlagt sju respondenter, två chefer och fem medarbetare. Av resultatet kan vi utläsa att både medarbetare och chefer är mycket positiva till utvecklingssamtal. Det viktigaste för båda parter verkar inte vara vad som sägs, utan att tiden tillsammans värderas högst. Kommunikationen verkar fungera förvånansvärt bra med tanke på att utvecklingssamtalen endast sker en gång per år, och både chef och medarbetare känner att de kan vara avslappnade och ärliga gentemot varandra. Av detta utläser vi en hög grad av både respekt och förtroende dem emellan. Något som dock skiljer sig mellan dem är synen på utvecklingssamtalets syfte och huruvida brus, det vill säga störningsmoment, förekommer. Andra faktorer som stod i fokus under våra intervjuer var relation, tid och lön vilka vi också har tittat närmare på i resultatdelen samt reflekterat över. Vi fann nämligen att tid är avgörande för hur utvecklingssamtalen upplevs samt hur kommunikationen fungerar parterna emellan. Även lönen står i fokus för de allra flesta respondenterna under dessa samtal.
153

An Assessment of the Interplay between the Shoulders and the Low Back in Occupational Tasks: A Manual Patient Handling Example

Belbeck, Alicia January 2010 (has links)
Redundancy and variation are characteristics of humans. Many muscles contribute to producing a movement at a joint, allowing different strategies for task performance. Further, the shoulders and back are involved in many tasks, including manual materials handling, but flexibility as to their relative roles in performing a task exists. In nursing, where manual patient handling (MPH) occurs daily, a risk of injury exists resulting from interactions with patients that may require awkward postures or sudden shifts in hand forces. Although some recommended MPH techniques have been advocated, many focus on lowering the risk of low back injury, without considering the effect of these techniques on other body regions. This study aimed to identify differences in shoulder and back physical exposures between performing self-selected and recommended patient handling techniques designed to reduce low back exposures. Twenty female participants performed three repetitions of five manual patient handling tasks using a self selected technique, followed by three repetitions of the same tasks using techniques learned in an interposed training session. Peak, mean and cumulative muscle activity, peak resultant moment, and ratings of perceived exertion were compared for each of the tasks before and after training, as well as identifying meaningful changes between the joints in mean population strength using a static strength prediction program. Significant decreases occurred at both the left and right shoulders and the low back for most measures, generally supporting the recommended techniques. Important exceptions existed, however, for the Sit-to-Chair tasks and Turn Toward tasks, where increases in several individual shoulder muscle activities, along with peak resultant moment, existed. Future recommendations for patient handling techniques should take into account potential negative exposures at the shoulders that may result from a back-centric injury avoidance paradigm.
154

INVESTIGATING THE FEASIBILITY OF NEW METHODS FOR ANALYSIS AND COLLECTION OF HUMAN MOTION IN FIELD APPLICATIONS

Godwin, ALISON 21 April 2009 (has links)
Despite a recent focus on understanding cumulative load, researchers still prefer to analyze the data using mean and peak values. At the same time, technological advancements have provided biomechanists with methods of collecting large amounts of data pertaining to joint loading. Waveform analysis offers another option that will become increasingly relevant, as wireless data collection devices become common place and provide access to waveforms from many hours of recording. The overall objectives of this research were to demonstrate some of the limits of current methods of biomechanical analysis, and introduce an alternative, and secondly, to propose a wireless system for use in field-based studies. An exploratory study using Functional Data Analysis (FDA) was completed on experimental lifting data. The results demonstrated that FDA can elucidate subtle differences in the curve shape outside of the peak areas typically used for statistical analysis that were attributed to fatigue. These findings support the need for a better understanding of how workers change their movement strategies as time progresses throughout the length of the workshift. To achieve this type of knowledge, a wireless data collection device utilizing inertial motion sensors (IMS) was introduced and validated for field use in the remaining three chapters. The IMS units in conjunction with an anthropometric model were tested against a traditional link segment model recorded in a gold-standard, video system. Testing that occurred in the entire reach space volume yielded errors as low as 5% for the lumbar moment, but errors also greatly exceeded 50% RMS error in some cases. Three hand switch alternatives were tested for their potential to provide external hand force timing and duration information to the link segment model, but none were found to be perfectly suitable in the current configuration. In conclusion, a wireless system based on IMS units has the potential to provide long-term data collection, but the development of the calibration routines and complexity of the underlying model must be improved. FDA was shown to have good potential for identifying subtle differences in curve shapes, and may become useful when long-term field-based data are readily available with the proposed IMS system. / Thesis (Ph.D, Kinesiology & Health Studies) -- Queen's University, 2009-04-21 09:01:22.968
155

Continuous relative phase variability of hand-held load carriage techniques: The effectiveness of a mover's assistive device

Smallman, CATHERINE 02 October 2012 (has links)
Professional furniture movers must carry objects of all shapes, sizes and weights. When carrying boxes between a house and the moving van, professional movers will carry boxes two different ways. The first way is holding the box in their hands in front of their body, and the second way is holding the box behind them and leaning forward so the box can rest on their backs while walking. The Mover’s Assistive Device (MAD) is an aid developed to decrease the effort of movers when carrying boxes and has been shown to reduce the amount of needed grip strength. The goals of this research were to compare the effects of technique (carrying in front or behind the body) as well as the effects of using the MAD on the way movers coordinate their 1) legs and 2) trunk and hips. Movement was tracked using a camera system and reflective markers attached to the participants. In study 1 ten male participants completed the four different carrying conditions on a treadmill. The different segments of the leg did not change coordination patterns between the front and back carries, however, the coordination was more stable (similar across all steps) in the front carry. When participants used the MAD, their legs moved in a more coordinated motion than when they did not use the MAD, and is considered to be useful in maintaining balance and control while carrying a box. In study 2 thirteen male participants completed the four different carrying conditions on a treadmill. The trunk and the hips did not change coordination between the front and back carries, but they became more coordinated when participants were wearing the MAD. A more coordinated motion between the trunk and hips is suggested to be beneficial to low back health. / Thesis (Master, Kinesiology & Health Studies) -- Queen's University, 2012-10-01 21:43:33.045
156

Quantification of Upper Extremity Physical Exposures of Materials Handling Tasks in Seated and Standing Configurations

Cudlip, Alan Christian 28 April 2014 (has links)
Prolonged periods in sitting or standing may negatively influence worker health. Integration of sit-stand workstations has attempted to mitigate these deleterious effects, and has generated positive results in terms of postural discomfort, injury risk and worker fatigue. Identification of how identical tasks are affected by sitting and standing is necessary to take advantage of loading differences between these configurations. The purpose of this research was to determine if differences in workplace configurations between seated and standing postures created changes in posture or muscular activity levels during manual materials handling tasks. Twenty male and twenty female participants performed four manual materials handling tasks: a 40N static push, a 40N static pull, a weighted bottle transfer set at 15% of the participant’s maximal arm elevation force, and a light assembly task in sitting and standing. Upper extremity electromyography was collected at 8 sites, and changes in local joint moments and body discomfort were calculated. Interactions between task and sit/stand configuration resulted in increases of up to 500% in some joint moments, 94% in EMG activity and 880% in some local body discomfort regions when tasks were completed in sitting. A main effect of sitting appeared primarily in joint moments and muscle activity, and generally resulted in increased loading in sitting. Important exceptions existed, which included resultant wrist joint loading 8.2 times larger in standing, and foot/shank discomfort increasing by up to 609%. Task differentially affected all EMG outputs, as well as most local joint moments and body discomfort regions. Future recommendations regarding upper extremity exposures during manual materials handling tasks should consider placing workers in standing postures instead of seated ones to minimize musculoskeletal loading to the upper extremity. In addition, the effects of task and sit/stand configuration should be considered in order to leverage differences between these positions, with tasks in standing generally resulting in decreased musculoskeletal disorder risks.
157

Análise da distribuição de cargas e das forças entre asseno e encosto, na postura sentada adequada

Resende, Fernanda de Lima e Sá [UNESP] 11 August 2006 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:28:34Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-08-11Bitstream added on 2014-06-13T20:37:39Z : No. of bitstreams: 1 resende_fls_me_guara.pdf: 781042 bytes, checksum: 90a752d449437b2098cb5b1a50b2cae7 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O objetivo deste trabalho foi estudar a distribuição das cargas no sistema cadeira plataforma de força (C-PF) e verificar se há correlação entre as forças medidas no assento e encosto, na postura sentada adequada. Participaram 38 voluntários, classificados pelo biótipo (32 mulheres e 6 homens): idade média de 43,92 anos, estatura média de 1,60 m e peso corporal médio de 65,10 kgf. Uma cadeira, com células de carga nas partes anterior e posterior do assento e no encosto, e uma plataforma de força mediram a distribuição do peso corporal. Estabeleceram-se várias correlações entre as variáveis (peso corporal, altura, idade, e índice de massa corporal) e as cargas medidas e entre as próprias forças adquiridas. Uma das correlações determinou uma relação entre a força total no assento e a força medida no encosto. A distribuição do peso corporal observada foi: 20,04% na plataforma de força; 45,33% e 30,43%, nas partes anterior e posterior do assento, respectivamente; e 4,20% no encosto. Não houve diferenças estatísticas significativas na comparação das médias dos valores da distribuição do peso corporal tanto entre os sexos como entre os biótipos. Porém, como há diferenças na forma corporal de acordo com os sexos e com os biótipos, houve certa diferença nos valores das forças medidas, no sistema C-PF. / The aim of this study was to study the load distribution in chair-force plate system (CFP) and to verify if there is correlation between measured seat and backrest forces in the adequate sitting posture. 38 volunteers participated of the study, classifieds according to physical types (32 female and 6 male): mean age of 43,92 years old, mean height of 1,60 m and mean body weight of 65,10 kgf. An instrumented office chair with load cells in the anterior and posterior portions of the seat and backrest and a force plate were used to measure the forces and body weight distribution in C-FP system. This study was established many correlations among some variables (body weight, height, age and body mass index) and the measured loads and among the acquired forces. One of these correlations determined a relation among total force measured on seat and acquired force on lumbar backrest. The body weight distribution observed in the C-FP system was: 20,04% in the force plate, 45,33% and 30,43% in the anterior and posterior portions of the seat respectively, and 4,20% in the backrest. There were no statistics significant differences in comparison of values weight distribution averages as between gender as between physical patterns. But, there are some differences in the body shape according to gender and physical patterns, it there was some difference in the values of acquired forces in the C-FP system.
158

Measurement and Analysis of Ergonomic Loads on Mechanical System Installers

January 2011 (has links)
abstract: Construction work is ergonomically hazardous, as it requires numerous awkward postures, heavy lifting and other forceful exertions. Prolonged repetition and overexertion have a cumulative effect on workers often resulting in work related musculoskeletal disorders (WMSDs). The United States spends approximately $850 billion a year on WMSDs. Mechanical installation workers experience serious overexertion injuries at rates exceeding the national average for all industries and all construction workers, and second only to laborers. The main contributing factors of WMSDs are ergonomic loads and extreme stresses due to incorrect postures. The motivation for this study is to reduce the WMSDs among mechanical system (HVAC system) installation workers. To achieve this goal, it is critical to reduce the ergonomic loads and extreme postures of these installers. This study has the following specific aims: (1) To measure the ergonomic loads on specific body regions (shoulders, back, neck, and legs) for different HVAC installation activities; and (2) To investigate how different activity parameters (material characteristics, equipment, workers, etc.) affect the severity and duration of ergonomic demands. The study focuses on the following activities: (1) layout, (2) ground assembly of ductwork, and (3) installation of duct and equipment at ceiling height using different methods. The researcher observed and analyzed 15 HVAC installation activities among three Arizona mechanical contractors. Ergonomic analysis of the activities using a postural guide developed from RULA and REBA methods was performed. The simultaneous analysis of the production tasks and the ergonomic loads identified the tasks with the highest postural loads for different body regions and the influence of the different work variables on extreme body postures. Based on this analysis the results support recommendations to mitigate long duration activities and exposure to extreme postures. These recommendations can potentially reduce risk, improve productivity and lower injury costs in the long term. / Dissertation/Thesis / M.S. Construction 2011
159

Quantifying Segmental Spinal Motion during Activities of Daily Living

Breloff, Scott 03 October 2013 (has links)
Back pain is a very common musculoskeletal impairment in most Americans. Average annual occurrence of back pain is reported around 30% of the population and is the most common cause of activity limitation in people younger than 45 years old. Eighty percent of the back pain presents in the lumbar spine. Although this ailment is very prevalent in the American population, there is a lack of empirical evidence supporting the common clinical diagnosis and intervention back pain strategies. The frequency of back pain and the lack of treatment methods were the motivation for this investigation. It is important to better understand spine dynamics during ambulatory tasks of daily activities to identify possible biomechanical mechanisms underlying back pain. Current biomechanical quantification methods for spine dynamics are either too invasive or not detailed enough to fully comprehend detailed spinal movement. Therefore, a non-invasive but detailed procedure to calculate spine dynamics was developed and tested. In this study, multi-segmented spine dynamics (kinematics and kinetics) were calculated during four activities of daily living (level walking (W), obstacle crossing (OC), stair ascent (SA) and stair descent (SD)). Our findings suggested an in-vivo multi-segmented spine surface marker set is able to detect different and repeatable motion patterns during walking among various spinal segments. The sacrum to lower lumbar (SLL) joint had the largest range of motion (ROM) when compared to the other more superior joints (lower lumbar to upper lumbar and upper lumbar to lower thoracic). Furthermore, SA task demonstrated more flexion ROM than both W and SD tasks. In addition to task influence, joints at different spine levels also demonstrated different ROMs, where SLL had a greater ROM than upper lumbar to lower thoracic (ULLT) in the transverse plane. Age was found to not significantly affect the segmental spinal ROM or peak angles. The vertical segmental joint reaction forces were different between tasks, where SD yielded larger vertical reaction forces than W. Overall, findings from this dissertation work were able to show that a multi-segment spine marker system could be an effective tool in determining different spinal dynamics during various activities of daily living. This dissertation includes unpublished co-authored material.
160

Análise ergonômica e intervenções nos postos de trabalho de operadores de caixa de supermercado (checkout)

Semensato, Cassiana Brosque [UNESP] 25 January 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:28:04Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-01-25Bitstream added on 2014-06-13T19:15:58Z : No. of bitstreams: 1 semensato_cb_me_bauru.pdf: 2350363 bytes, checksum: 71efa3a3bbaaaaeeab6563277bfaa934 (MD5) / Universidade Estadual Paulista (UNESP) / O ambiente de trabalho deve favorecer o bom desempenho das atividades dos colaboradores, pois reflitirá na produtividade e na lucratividade da empresa. Por isso, o conhecimento de técnicas ergonômicas, tem gerado muitos benefícios tanto para o empregado quanto para o empregador. Estas adequações permitem reduções nos custos e vão desde o cumprimento das normas da NBR-17, até diminuição de afastamentos de trabalho por doencas de esforço repetitivo ás melhorias ambientais que atingem diretamente a produtividade. Este estudo tem como objetivo identificar e analisar as condições ergonômicas que interferem nas atividades laborais dos operadores de caixa, analisando os agentes ergonômicos pertinentes à atividade desenvolvida, visando à melhoria das condições operacionais e organizacionais de suas atividades. No desenvolvimento do trabalho, realizou-se a análise ergonômica dos postos de trabalho de um supermercdo visando o conforto dos trabalhadores conforme determina a NR-17 - Ergonomia, através de dois Laudos Ergonômicos. Para avaliação dos postos de trabalho, dividiu-se a pesquisa em três etapas: na primeira etapa realizou-se a avaliação dos postos de trabalho dos operadores de caixa (checkout), através de um Laudo Ergonômico, buscando as intervenções ergonômicas necessárias, na segunda etapa, foram passadas as orientações da NR-17 para a compra dos novos checkouts. E na terceira e última etapa, foi feito o segundo laudo para a análise destes novos checkouts, para confirmação do objetivo inicial, que era o cumprimento das normas regulamentares. Neste estudo quase todos os critérios da NR 17 foram cumpridos em relação ao posto de trabalho (checkouts), porém este estabelecimetno está de acordo com o cronograma imposto pelo Anexo I da NR17 / The work environment should favor the good performance of the employees activities, because will reflect in the company productivity and profitabililty. Therefore, knowledge of ergonomic techniques, has generated many benefits for both the employee and the employer. These adjustments lead to reductions in costs, ranging from the norms of NBR17, even a reduction in absences from work due to diseases of repetitive stress the environmental improvements that directly affect productivity. This study aims to identify and analyze ergonomic conditions that interfere in the labor activities of cash operators, analyzing the ergonomic agents relevant to the activity performed, aiming at the improvement of operational and organizational activities. In developing this work, carried out the ergonomic analyzis of the positions work of a supermarket to ensure the comfort workers as require the NR-17 - Ergonomics, through two Ergonomic Reports. For the evaluation of jobs, the survey was divided into three stages: the first step was conducted to evaluate the jobs in cashiers (checkout) through an Ergonomic Report, seeking the necessary ergonomic interventions in second stage, were passed the guidelines of the NR17 to purchase the new checkouts. And in the third and final stage, it was made the second report to examine these new checkouts, to confirmation the initial goal, which was the fulfillment or regulation standards. In this study almost all the features of NR was implemented regarding to the jobs (checkouts), but this property is consistent with the timeline imposed by Annex I of NR17

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