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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.
111

The effects of light and dark character CRT displays upon VDT operator performance, eye scanning Behavior, pupil diameter and subjective comfort/discomfort

Kothari, Nimesh C. January 1986 (has links)
No description available.
112

Réactivité posturale et inconfort subjectif induits par un stimulus visuel

Hanssens, Jean-Marie 01 1900 (has links)
Il est bien connu des professionnels de la vision que l’ajustement des verres progressifs sur un patient presbyte peut induire de l’inconfort et des difficultés posturales (Timmis, Johnson, Elliott, & Buckley, 2010). Ces plaintes sont directement associées à l’information visuelle perçue à travers les verres progressifs. Le principal objectif de cette thèse est d’identifier quels sont les paramètres d’un stimulus visuel (p.ex. fréquence temporelle ou vélocité) à l’origine de la perturbation posturale et de l’inconfort. Les distorsions dynamiques perçues à travers des verres progressifs s’apparentent aux mouvements d’un bateau qui roule de droite à gauche ou qui tangue d’avant en arrière. Ce type de stimulation visuelle a été reproduit dans une voute d’immersion en réalité virtuelle avec un sol à texture de damier noir et blanc qui oscillait périodiquement de droite à gauche et d’avant en arrière à différentes fréquences et amplitudes. Les études qui portent sur ce sujet montrent que la réponse posturale induite visuellement augmente avec la vélocité de stimulation et diminue lorsque la fréquence augmente. Cette information peut paraitre contradictoire, car ces deux variables sont liées entre elles par l’amplitude et covarient dans le même sens. Le premier objectif de cette thèse était de déterminer les causes possibles de cette contradiction. En faisant varier la fréquence temporelle de stimulation visuelle, on retrouve deux domaines de réponse posturale. Le premier domaine correspond aux fréquences inférieures à 0,12 Hz. Dans ce domaine, la réponse posturale est visuodépendante et augmente avec la vélocité du stimulus. Le second domaine postural correspond aux fréquences supérieures à 0,25 Hz. Dans ce domaine, la réponse posturale sature et diminue avec l’augmentation de la fréquence. Cette saturation de la réponse posturale semble causée par des limitations biomécaniques et fréquentielles du système postural. D’autres études ont envisagé d’étudier l’inconfort subjectif induit par des stimuli visuels périodiques. Au sein de la communauté scientifique, deux théories principales se confrontent. La théorie sensorielle repose sur les conflits sensoriels induit par le stimulus visuel tandis que la théorie posturale suggère que l’inconfort est la conséquence de l’instabilité posturale. Nos résultats révèlent que l’inconfort subjectif induit par une stimulation visuelle dynamique dépend de la vélocité du stimulus plutôt que de sa fréquence. L’inconfort peut être prédit par l’instabilité naturelle des individus en l’absence de stimulus visuel comme le suggère la théorie posturale. Par contre, l’instabilité posturale induite par un stimulus visuel dynamique ne semble pas être une condition nécessaire et suffisante pour entrainer de l’inconfort. Ni la théorie sensorielle ni la théorie posturale ne permettent à elles seules d’expliquer tous les mécanismes à l’origine de l’inconfort subjectif. Ces deux théories sont complémentaires, l’une expliquant que l’instabilité intrinsèque est un élément prédictif de l’inconfort et l’autre que l’inconfort induit par un stimulus visuel dynamique résulte d’un conflit entre les entrées sensorielles et les représentations acquises par l’individu. / It is well know by eye care professionals that fitting progressive lenses on a presbyopic patient can induce some discomfort and postural difficulties (Timmis, Johnson, Eliott, & Buckley, 2010). The complaints are directly related to the visual information seen through progressive lenses. The main objective of this thesis is to identify the parameters of a visual stimulus (e.g. temporal frequency or velocity) causing the postural perturbation and discomfort. Dynamic distortions perceived in progressive lenses are similar to movements of a boat that rolls from side to side or pitches back and forth. This type of stimulation was reproduced in a full immersive virtual environment with simulated a black and white checkerboard at floor level. This checkerboard periodically swayed at different frequencies and amplitudes. Studies on this topic reveal that visually induced postural responses increase with stimulus velocity and decrease as frequency increases. This information may seem contradictory because these two variables are linked by the amplitude and covary in the same direction. The first objective was to determine the possible causes of this contradiction. Our results show that the postural response to the visual stimulus can be divided into several different areas depending on the frequency range. The first area corresponds to frequencies below 0,12Hz. In this category, postural response is dependent on visual information and increased with stimulus velocity. The second area corresponds to frequencies above 0,25Hz. In this category, postural response saturates and decreases with increasing frequency. This saturation seems to be caused by biomechanical and frequency limitations of the postural system. Other studies have examined subjective discomfort induced by periodic visual stimuli. In the scientific community, two main theories exist: the sensory conflict theory and the postural instability theory. The first theory is based on sensory conflicts induced by the visual stimulus while the second theory suggests that postural discomfort is the result of postural instability. Our results show that subjective discomfort induced by dynamic visual stimulation depends on the velocity of the stimulus rather than its frequency. Discomfort can be predicted by the natural instability of individuals in the absence of visual stimuli as suggested by the postural theory. However, postural instability induced by a dynamic visual stimulus is neither necessary nor sufficient to cause discomfort. According to our results, neither the sensory conflict theory, nor the postural instability theory on their own can explain all the mechanisms behind the appearance of subjective discomfort. These two theories are complementary, one explaining that the intrinsic instability is a predictor of discomfort; the other that discomfort induced by a dynamic visual stimulus involves a conflict between sensory input and representations obtained by the individual.
113

Ingestão de bicarbonato de sódio e cloreto de amônio e seus efeitos sobre o ritmo de prova, desempenho e equilíbrio ácido-base em um teste contrarrelógio de ciclismo de 4km / Sodium bicarbonate and ammonium chloride ingestion and their effects on pacing, performance and acid-base balance during a 4-km cycling time trial

Oliveira, Carlos Rafaell Correia de 09 June 2016 (has links)
Nós determinamos a influência da alcalose e acidose metabólica induzida sobre o ritmo de prova, gasto energético e desempenho durante um teste contrarrelógio de ciclismo de 4 km (TCR). Após um estudo preliminar (N=7) determinando as doses ótimas de cloreto de amônio (NH4Cl), bicarbonato de sódio (NaHCO3) e placebo (carbonato de cálcio, CaCO3), 11 ciclistas amadores realizaram um TCR de 4 km 100 min após ingerirem 0,15 g·kg-1 de NH4Cl, 0,3 g·kg-1 de NaHCO3 ou 0,15 g·kg-1 de CaCO3 (desenho de medidas repetidas, contrabalançado e duplo-cego). Comparado com placebo, a ingestão de NaHCO3 resultou em uma alcalose sanguínea pré-exercício (pH: + 0,06 ± 0,04, [HCO3-]: + 4,7 ± 2,6 mmol?L-1, excess de base: + 4,6 ± 2,4 mmol?L-1, P<0,05), enquanto que o NH4Cl resultou em uma acidose sanguínea (pH: - 0,05 ± 0,04, [HCO3-]: - 5,5 ± 2,9 mmol?L-1, excesso de base: - 5,3 ± 2,5 mmol?L-1, P<0.05), com essas diferenças permanecendo durante todo o teste. Apesar de nenhum desconforto gastrointestinal severo, os participantes adotaram um ritmo de prova significativamente mais conservador em NH4Cl comparado com placebo e NaHCO3, que foi acompanhado por uma redução na taxa de gasto energético anaeróbio (~ -14 %, P<0,05) e menor trabalho anaeróbio total (~ -13 %, P<0,05). Consequentemente, o desempenho foi prejudicado em NH4Cl (~ -7 %) comparado com as demais condições (P<0,05). O lactato plasmático, VCO2 e a PetCO2 foram menores e a VE/VCO2 maior durante o TCR em acidose do que em placebo e alcalose (P<0,05). Entretanto, não houve diferença para essas variáveis entre placebo e NaHCO3 (P<0,05). A acidose metabólica induzida diminuiu o ritmo de prova e o metabolismo anaeróbio, além de prejudicar o desempenho durante um TCR de 4 km, independente de desconforto gastrointestinal / We determined the influence of induced metabolic alkalosis and metabolic acidosis on pacing, energy expenditure and performance during a 4-km cycling time trial (TT). After a preliminary study (N=7) determining the optimal ammonium chloride (NH4Cl), sodium bicarbonate (NaHCO3), and placebo (calcium carbonate, CaCO3) doses, 11 amateur cyclists performed a 4-km TT 100 min after ingesting either 0.15 g·kg-1 of body mass of NH4Cl, 0.3 g·kg-1 of NaHCO3 or 0.15 g·kg-1 of CaCO3 (double-blind, counterbalanced and repeated-measures design). Compared with placebo, the NaHCO3 ingestion resulted in a pre exercise blood alkalosis (pH: +0.06 ± 0.04, [HCO3-]: +4.7 ± 2.6 mmol?L-1, base excess: +4.6 ± 2.4 mmol?L-1, P<0.05), while NH4Cl resulted in a blood acidosis (pH: -0.05 ± 0.04, [HCO3-]: -5.5 ± 2.9 mmol?L-1, base excess: -5.3 ± 2.5 mmol?L-1, P<0.05), with these differences remaining throughout the trial. Despite no gastrointestinal distress, participants adopted a significant more conservative pacing in NH4Cl compared with placebo and NaHCO3, which was accompanied by a reduced anaerobic energy expenditure rate (~ -14 %, P<0.05) and lower total anaerobic work (~ -13 %, P<0.05). Consequently, the performance was less in NH4Cl (~ -7 %) compared with other conditions (P<0.05). Plasma lactate, VCO2 and PetCO2 were lower and the VE/VCO2 higher during the TT in acidosis than in placebo and alkalosis (P<0.05). However, there was no difference for these variables between placebo and NaHCO3 (P>0.05). Induced metabolic acidosis slows pacing, decreases anaerobic metabolism and impairs performance during a 4-km TT, independent of gastrointestinal distress
114

Développement d’un outil numérique personnalisable pour l’évaluation de l’inconfort et de la fatigue du passager d’avion / Development of a customizable digital tool for assessing aircraft passenger discomfort and fatigue

Savonnet, Léo 09 March 2018 (has links)
La position assise peut être source d'inconfort, particulièrement en avion lors des vols longcourriers. Cet inconfort provient en partie de facteurs mécaniques liés à l'interaction entre le siège et le passager. Disposer de modèles biomécaniques pouvant simuler cette interaction et estimer ces facteurs permettrait d'optimiser le design du siège d'avion lors de sa phase de conception afin d'améliorer son ergonomie et réduire l'inconfort du passager. L'objectif de cette thèse est de développer un outil numérique permettant d'estimer les facteurs mécaniques menant à l'inconfort et la fatigue des passagers. Cet outil combine deux différents types de modèles. Un modèle éléments finis permettant de simuler la déformation des tissus sous-cutanés et un modèle corps rigides permettant d'estimer les efforts musculaires et articulaires. Une méthode de couplage des deux modèles a été développée permettant ainsi de simuler une position à partir de laquelle l'ensemble des facteurs d'inconfort sont estimés. Un modèle éléments finis a été développé après avoir fait une étude de sensibilité sur les différents paramètres de modélisation (maillage, géométrie, lois matériaux). Un modèle corps rigides développé par Anybody a été utilisé pour être couplé avec ce modèle éléments finis. Cette méthode de couplage itératif entre les deux modèles a permis de réaliser un ajustement de la posture initiale dans le siège. Afin de simuler l'ensemble de la population et sa grande diversité morphologique, un modèle surfacique paramétrique a été développé à partir de données 3d expérimentales, ce modèle surfacique permettant ainsi d'obtenir un modèle éléments finis représentant tout type d'anthropométrie. Différents processus de validation ont été effectués à l'aide de données et d'un modèle « sujetspécifique ». Les données de pression externe simulées ont été comparées à des données expérimentales. Une étude expérimentale sous IRM ouvert a permis de mesurer les déformations des différents tissus sous-cutanés afin de les comparer aux données simulées. Un outil numérique est donc aujourd'hui disponible pour simuler l'impact du siège sur les passagers, cependant de futures études devraient se concentrer d'une part sur les modèles en étudiant la variation morphologique interne inter individus, le positionnement dans le siège ainsi que l'influence du temps sur les tissus mous et d'autres part sur la définition de critères d'inconfort et de fatigue (inconfort considéré sur des temps longs représentatifs d'un vol long-courrier) / The sitting position could be a source of discomfort, in particular in a long haul flight. This discomfort comes partially from mechanical factors linked to the interaction between the passenger and the seat. Having biomechanical models which can simulate this interaction and estimate these factors would allow optimizing the seat design in its conception phase to improve it ergonomic quality and reduce the passenger discomfort. The objective of this thesis is to develop a digital tool allowing estimating the mechanical factors leading to discomfort and fatigue of the passenger. This tool assemble two kinds of models, a finite element model allowing to simulate the sub dermal tissue deformation and a multibody model allowing to estimate the muscular and joint forces. A coupling method of the two models have been developed allowing simulating a position from where the all discomfort factors are estimated. A finite element model has been developed after having done a sensitivity analysis on the different model parameters (mesh, geometry, material law). A multibody model developed by Anybody was used to be associated with this finite element model. This iterative coupling method between the two models allowed realizing an adjustment of the initial posture in the seat. To simulate the whole population and is large morphological diversity, a parametric shape model was developed from 3d experimental data, this shape model allowing to obtain a finite element model representing any kind of anthropometry. Different validation processes have been realized with experimental data and subject-specific model. The simulated extern pressures were compared to experimental data. An experimental study done in an open MRI allowed to measure the different subcutaneous tissue to compare it to the simulated data. A digital tool is consequently now available to simulate the impact of the seat on the passenger, however future studies should focus on the one hand on the models studying the internal morphological variations between people, the person positioning in the seat, the time influence on the soft tissue and on the other hand on the discomfort and fatigue criteria
115

THE HUMAN COSTS AND BENEFITS OF WORK: JOBLOAD, SELF-PERCEIVED PERFORMANCE, AND EMPLOYEE WELLBEING.

Miller, Peta, Peta.Miller@dewr.gov.au, petajohnmiller@bordernet.com.au January 2004 (has links)
The primary purpose of this project was to investigate some relationships between workload and employee wellbeing. The necessary first stage was to formulate a theoretical framework � the JobLoad Model � to support a comprehensive and detailed investigation of the main factors that contribute to a job's workload. Building on the ergonomics concept of �workload�, this Model incorporates task- and job-level factors that have been identified within the research literatures of physical and cognitive ergonomics as important; additional constructs were added to take account of additional factors shown to be relevant to employee wellbeing, drawing on evidence from occupational health and organizational psychology literatures. Using this framework, available questionnaire-based measurement instruments for assessing workload and employee wellbeing were reviewed, new items were developed as required, and the JobLoad Index (JLI) was developed. The JLI was used to collect data from public servants in two different workplaces, with participation rates of 63% and 73% respectively. Relationships were determined between major task, job and organisational environment factors, self-perceived performance adequacy, and various aspects of employee wellbeing including job satisfaction, physical discomfort and psychological fatigue, stress and arousal. For a sub-sample of participants in one of the two workplaces, levels of adrenaline, noradrenaline and cortisol were also measured from 24-hour urine collections. The factors measured by the JLI accounted for a very substantial proportion of variance in these various dimensions of work-related wellbeing. The results provide potentially very useful insights into the relative influences of a wide range of work- and job-related variables on people's perceived abilities to cope with their job demands, and on several aspects of their wellbeing. Further, the importance of measuring multiple dimensions of wellbeing, and differentiating their separate sets of work-related determinants, was well demonstrated. Finally, and perhaps most significantly, this study has identified the powerful role that self-perceived performance plays as an intervening variable between job demands and people's work-related wellbeing.
116

Patientens upplevelse av akupunktur som behandling vid ångest / Patient’s experience of acupuncture as anxiety treatment

Dahlstedt, Sara, Färdig, Pernilla January 2015 (has links)
Bakgrund: Ångest är en folksjukdom som cirka 25 % av befolkningen drabbas av någon gång i sitt liv. Behandlingsmetoderna är få, så som läkemedelsbehandling, och innebär ofta ett patogent förhållningssätt till patienten. Ett av sjuksköterskans ansvarsområden är omvårdnad, och enligt kompetensbeskrivningen ska hen främja hälsa och omvårdnad med ett salutogent förhållningssätt. Integrativ vård, så som akupunktur, riktar sig mot att främja just hälsa och det salutogena. Akupunktur används idag inom psykiatrin, men ingår inte i sjuksköterskans grundutbildning. Information om behandling och effekt förväntas ändå att ges trots den bristande kunskapen. Syfte: Syftet var att ur ett patientperspektiv beskriva upplevelsen av akupunkturbehandling vid ångest. Metod: Litteraturstudien bygger på sex kvalitativa artiklar, som hämtats från olika databaser. En manifest innehållsanalys gjordes för att få fram den data ur artiklarna som svarade an på syftet och som bildade resultatet. Resultat: Det framkom tre kategorier av patientens upplevelse, dessa var: lindring, oro samt hopp och välmående. Majoriteten av patienterna upplevde en stark ångestlindring och svarar då an på den här studiens syfte. Övriga upplevelser var att läkemedelsbehovet kunde minskas, och att akupunkturbehandlingen gav en känsla av hopp och ökat välmående. Ett visst obehag kunde infinna sig hos patienterna. Trots obehag upplevde samtliga patienter behandlingen som mycket positiv. Slutsats: Denna studie styrker akupunkturens lindrande effekt på ångest och positiva inverkan på omvårdnad. Författarnas förförståelse har blivit bekräftad. Det finns svagheter i studien gällande generaliserbarhet, grundat i det bristande underlaget, samt tillförlitlighet gällande författarnas bristande erfarenheter att utföra en liknande studie. Mer forskning krävs inom ämnet. / Background: Anxiety is a common disease that approximately 25% of Sweden's population suffers from at some point in their lives. The treatment methods are few and often imply a pathogenic approach to the patient, such as drug treatment. One of the nurse's area of responsibility is patient care, and according to the nurse's competence description he or she shall promote health and nursing with a salutogenic approach. Integrative medicine, as acupuncture, is aimed at promoting health and the salutogenic. Acupuncture is used today in psychiatry, but is not included in the nurse education, information about treatment and efficacy are expected to be given despite the lack of knowledge. Objective: The objective was that from a patient perspective describe the experience of acupuncture treatment for anxiety. Method: The literature study is based on six qualitative articles, taken from different databases. A manifest content analysis was done to obtain the data from the articles who responded to their purpose and which formed the result. Results: Three categories of patient experience were found, these were: relief, discomfort and hope and well being. The majority of patients experienced a strong anxiety relief and then responds to the purpose of this study. Other experience was that medicine needs were reduced and that the acupuncture treatment gave a sense of hope and increased well being. Some discomfort could appear in the patients. Despite the discomfort, all patients experienced the treatment as very positive. Conclusion: This study proves acupuncture effect on relieving anxiety and positive impact on nursing care. The authors' preconception has become probable. There are weaknesses in the study that concerns generalizability due to the lack of existing research as well as reliability in the authors' lack of experience to carry out a similar study. More research is needed on the subject.
117

Methoden und Mittel zur Verbesserung des statischen und dynamischen Muskelverhaltens bei haltungsbedingten Beschwerden:ein Trainings- und bewegungswissenschaftlicher Vergleich zwischen haltungsverbessernden, sensomotorischen Einlegesohlen und einem gesundheitsorientiertem, rehabilitativen Muskelaufbautraining / Methods and means to improve the statically and dynamic muscle behaviour of posture-conditioned discomfort: a training and biomechanical theory comparison between posture-improving Sensomotoric Insoles and a rehabilitatives muscle construction training

Ohlendorf, Daniela 09 April 2008 (has links)
No description available.
118

Réactivité posturale et inconfort subjectif induits par un stimulus visuel

Hanssens, Jean-Marie 01 1900 (has links)
Il est bien connu des professionnels de la vision que l’ajustement des verres progressifs sur un patient presbyte peut induire de l’inconfort et des difficultés posturales (Timmis, Johnson, Elliott, & Buckley, 2010). Ces plaintes sont directement associées à l’information visuelle perçue à travers les verres progressifs. Le principal objectif de cette thèse est d’identifier quels sont les paramètres d’un stimulus visuel (p.ex. fréquence temporelle ou vélocité) à l’origine de la perturbation posturale et de l’inconfort. Les distorsions dynamiques perçues à travers des verres progressifs s’apparentent aux mouvements d’un bateau qui roule de droite à gauche ou qui tangue d’avant en arrière. Ce type de stimulation visuelle a été reproduit dans une voute d’immersion en réalité virtuelle avec un sol à texture de damier noir et blanc qui oscillait périodiquement de droite à gauche et d’avant en arrière à différentes fréquences et amplitudes. Les études qui portent sur ce sujet montrent que la réponse posturale induite visuellement augmente avec la vélocité de stimulation et diminue lorsque la fréquence augmente. Cette information peut paraitre contradictoire, car ces deux variables sont liées entre elles par l’amplitude et covarient dans le même sens. Le premier objectif de cette thèse était de déterminer les causes possibles de cette contradiction. En faisant varier la fréquence temporelle de stimulation visuelle, on retrouve deux domaines de réponse posturale. Le premier domaine correspond aux fréquences inférieures à 0,12 Hz. Dans ce domaine, la réponse posturale est visuodépendante et augmente avec la vélocité du stimulus. Le second domaine postural correspond aux fréquences supérieures à 0,25 Hz. Dans ce domaine, la réponse posturale sature et diminue avec l’augmentation de la fréquence. Cette saturation de la réponse posturale semble causée par des limitations biomécaniques et fréquentielles du système postural. D’autres études ont envisagé d’étudier l’inconfort subjectif induit par des stimuli visuels périodiques. Au sein de la communauté scientifique, deux théories principales se confrontent. La théorie sensorielle repose sur les conflits sensoriels induit par le stimulus visuel tandis que la théorie posturale suggère que l’inconfort est la conséquence de l’instabilité posturale. Nos résultats révèlent que l’inconfort subjectif induit par une stimulation visuelle dynamique dépend de la vélocité du stimulus plutôt que de sa fréquence. L’inconfort peut être prédit par l’instabilité naturelle des individus en l’absence de stimulus visuel comme le suggère la théorie posturale. Par contre, l’instabilité posturale induite par un stimulus visuel dynamique ne semble pas être une condition nécessaire et suffisante pour entrainer de l’inconfort. Ni la théorie sensorielle ni la théorie posturale ne permettent à elles seules d’expliquer tous les mécanismes à l’origine de l’inconfort subjectif. Ces deux théories sont complémentaires, l’une expliquant que l’instabilité intrinsèque est un élément prédictif de l’inconfort et l’autre que l’inconfort induit par un stimulus visuel dynamique résulte d’un conflit entre les entrées sensorielles et les représentations acquises par l’individu. / It is well know by eye care professionals that fitting progressive lenses on a presbyopic patient can induce some discomfort and postural difficulties (Timmis, Johnson, Eliott, & Buckley, 2010). The complaints are directly related to the visual information seen through progressive lenses. The main objective of this thesis is to identify the parameters of a visual stimulus (e.g. temporal frequency or velocity) causing the postural perturbation and discomfort. Dynamic distortions perceived in progressive lenses are similar to movements of a boat that rolls from side to side or pitches back and forth. This type of stimulation was reproduced in a full immersive virtual environment with simulated a black and white checkerboard at floor level. This checkerboard periodically swayed at different frequencies and amplitudes. Studies on this topic reveal that visually induced postural responses increase with stimulus velocity and decrease as frequency increases. This information may seem contradictory because these two variables are linked by the amplitude and covary in the same direction. The first objective was to determine the possible causes of this contradiction. Our results show that the postural response to the visual stimulus can be divided into several different areas depending on the frequency range. The first area corresponds to frequencies below 0,12Hz. In this category, postural response is dependent on visual information and increased with stimulus velocity. The second area corresponds to frequencies above 0,25Hz. In this category, postural response saturates and decreases with increasing frequency. This saturation seems to be caused by biomechanical and frequency limitations of the postural system. Other studies have examined subjective discomfort induced by periodic visual stimuli. In the scientific community, two main theories exist: the sensory conflict theory and the postural instability theory. The first theory is based on sensory conflicts induced by the visual stimulus while the second theory suggests that postural discomfort is the result of postural instability. Our results show that subjective discomfort induced by dynamic visual stimulation depends on the velocity of the stimulus rather than its frequency. Discomfort can be predicted by the natural instability of individuals in the absence of visual stimuli as suggested by the postural theory. However, postural instability induced by a dynamic visual stimulus is neither necessary nor sufficient to cause discomfort. According to our results, neither the sensory conflict theory, nor the postural instability theory on their own can explain all the mechanisms behind the appearance of subjective discomfort. These two theories are complementary, one explaining that the intrinsic instability is a predictor of discomfort; the other that discomfort induced by a dynamic visual stimulus involves a conflict between sensory input and representations obtained by the individual.
119

THE HUMAN COSTS AND BENEFITS OF WORK: JOBLOAD, SELF-PERCEIVED PERFORMANCE, AND EMPLOYEE WELLBEING.

Miller, Peta, Peta.Miller@dewr.gov.au, petajohnmiller@bordernet.com.au January 2004 (has links)
The primary purpose of this project was to investigate some relationships between workload and employee wellbeing. The necessary first stage was to formulate a theoretical framework � the JobLoad Model � to support a comprehensive and detailed investigation of the main factors that contribute to a job's workload. Building on the ergonomics concept of �workload�, this Model incorporates task- and job-level factors that have been identified within the research literatures of physical and cognitive ergonomics as important; additional constructs were added to take account of additional factors shown to be relevant to employee wellbeing, drawing on evidence from occupational health and organizational psychology literatures. Using this framework, available questionnaire-based measurement instruments for assessing workload and employee wellbeing were reviewed, new items were developed as required, and the JobLoad Index (JLI) was developed. The JLI was used to collect data from public servants in two different workplaces, with participation rates of 63% and 73% respectively. Relationships were determined between major task, job and organisational environment factors, self-perceived performance adequacy, and various aspects of employee wellbeing including job satisfaction, physical discomfort and psychological fatigue, stress and arousal. For a sub-sample of participants in one of the two workplaces, levels of adrenaline, noradrenaline and cortisol were also measured from 24-hour urine collections. The factors measured by the JLI accounted for a very substantial proportion of variance in these various dimensions of work-related wellbeing. The results provide potentially very useful insights into the relative influences of a wide range of work- and job-related variables on people's perceived abilities to cope with their job demands, and on several aspects of their wellbeing. Further, the importance of measuring multiple dimensions of wellbeing, and differentiating their separate sets of work-related determinants, was well demonstrated. Finally, and perhaps most significantly, this study has identified the powerful role that self-perceived performance plays as an intervening variable between job demands and people's work-related wellbeing.
120

Percepção de desconforto no uso de brincos : relação das característica sociodemográficas, morfoantropométricas, dos hábitos relacionados ao uso e da preferência quanto ao tipo de produto / Earring discomfort perception: relationship between social demographic, morpho anthropometric characteristics and product type preferences and habits of wearing earrings

Strobel, Elisa 30 July 2014 (has links)
Made available in DSpace on 2016-12-12T20:17:55Z (GMT). No. of bitstreams: 1 118604.pdf: 5890822 bytes, checksum: d70b354d67e20081b2cad602742a22c8 (MD5) Previous issue date: 2014-07-30 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Surveying sociodemographic, morpho-anthropometric characteristics in women, related to their habits and product preferences wearing earrings, aiming to verify the relationship of these domains with the perception of discomfort. Discomfort was assessed using descriptors. The earlobe thickness and earring dimensions used by the participant on the day of data collection were measured with a digital micrometer, universal caliper and a digital scale. The ear and earlobe shape and the earring hole were classified according to the literature. 208 adult women, were surveyed separated by age groups. Parametric data are presented as mean and standard deviation and non-parametric as frequency distributions. The correlations between the variables were then verified. 80.3% women answered that they wear earrings on a daily-basis and all individuals reported some degree of discomfort, from slight (13.6%), to moderate (26.9%) or severe (59.1%). The average earlobe thickness was 5.80 ± 0.83 mm (left). 58% of the lobules were classified as dettached, and 42% as attached (left). The most widely used type of earring was the stud type, followed by the dangling type and at last the hoop. 77.7% wore earrings that weighed between 0.1 g to 2.5 g on the day of data collection. We conclude that for this sample, the discomfort in the use of earrings is mainly related to product characteristics. The mass and then the material were more associated with discomfort in the use of earrings. Ergonomic recommendations and opportunities for improvement are then presented. / O objetivo deste estudo foi avaliar a relação das características sociodemográficas, morfoantropométricas, dos hábitos relacionados ao uso e da preferência quanto ao tipo de produto com a percepção de desconforto no uso de brincos em mulheres. O desconforto foi avaliado por meio de descritores. A espessura dos lóbulos, e dimensões do brinco utilizado pela participante na data da coleta foram medidos com mícrômetro digital, paquímetro universal e balança digital. A forma geral da orelha externa, do lóbulo e o furo foram aferidos de acordo com a literatura. Foram pesquisadas 208 mulheres maiores de idade, separadas por faixa etária. Os dados paramétricos foram descritos por média e desvio padrão, os não-paramétricos por distribuições de frequências. Foram ainda testadas as correlações entre as variáveis. 80,3% da amostra usa brincos todos os dias e todos os indivíduos se enquadraram em algum nível de desconforto leve (13,6%), moderado (26,9%) ou grave (59,1%). A média da espessura do lóbulo foi 5,80±0,83mm (esquerdo). 58% dos lóbulos foi aferida como solto, e 42% como preso (esquerdo). O tipo de brinco mais usado foi o inteiro, seguido do pêndulo e argola. 77,7% usava brincos que pesavam entre 0,1g a 2,5g na data da coleta. Conclui-se que para esta amostra, as questões quanto ao desconforto no uso de brincos são principalmente relacionados às características do produto. A massa do brinco seguida do material foram os aspectos mais associadas ao desconforto no uso de brincos. Por fim são apresentadas recomendações ergonômicas e oportunidades de melhoria.

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