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231.
This research used distal motor latency (DML) and vibration thresholds (VT) to evaluate 84 hand activity and wrist deviation combinations to determine the best association with carpal tunnel syndrome (CTS). Female volunteers, 2 healthy and 2 CTS diagnosed, were age matched and operated a keyboard for 4 hrs a day. Room temperature was 28°C(±2). Beginning DML and VT were taken with a relaxed neutral posture hand. The wrist was deviated in a randomly selected combination, and determinations were taken at 5-min intervals. The trial ended at 20 min or when discomfort was felt. The CTS conditions were discriminated by pain four times, DML once, and VT 14 times. Vibrometry was the most consistent CTS discriminator. The best VT results for wrist positions were obtained with wrist extension and extended extension, whereas the unclenched, clenched, and loaded power grip activities proved to be the most consistent hand activities.  相似文献   
232.
A virtual environment is an interactive graphic system mediated through computer technology that allows a certain level of reality or a sense of presence to access virtual information. To create reality in a virtual environment, ergonomics issues are explored in this paper, aiming to develop the design of presentation formats with related information, that is possible to attain and to maintain user-friendly application.  相似文献   
233.
Abstract

In many studies, ergonomics has been shown to influence human performance. The aim of this paper was to demonstrate imp ortan t ergonomics influences on quality in industrial production, from the perspective of interactions between humans, technology, organization, and work environment. A second aim was to elab orate on the implications of these findings for the development of quality management strategies. This paper shows that ergonomics problems in terms of adverse work environmental conditions, in appropriate design of technology, and an unsuitable org an izatio n are important causes of quality deficiencies. Problem solving aimed at improving ergonomics, quality, and productivity simultaneously is likely to obtain sup po rt from most of the interest parties of the company, and may also enhance participation. Ergonomics has the potential of becoming a driving force for the development of new quality management strategies.  相似文献   
234.
Using the results of psychophysical and biomechanical experiments, NIOSH (National Institute for Occupational Safety and Health) Recommended Weight Limit (RWL), the Lifting Index (LI), the form of the asymmetry multiplier, and the criterion for compression force were investigated. Analysis of the results indicated a significant difference between the NIOSH RWL and the reported Maximum Acceptable Weight of Lift (MAWL). Contrary to the NIOSH lifting equation, the form of the asymmetry multiplier was found to be non-linear. The overall average of peak compression force on the L5/S1 was 3685 N. Fifty-eight percent of all compression forces reported in the biomechanical experiment were found to exceed the suggested 3400 N set by NIOSH guidelines. These results support previous research findings on the validity of NIOSH guidelines.  相似文献   
235.
A visual-visual dual computer task was designed to test the effect of the thermal environment on dual task performance. The temperatures selected for testing were 20 and 35 °C Wet Bulb Globe Temperature (WBGT). 34 volunteers were randomly assigned to 1 of the 2 temperature conditions. Individual differences in single task performance were controlled by equating the baselines of single task performance. Once individual differences in single task capacity were controlled, statistically significant differences in performance were demonstrated. Mean accuracy was computed over a 1-hr testing period in each temperature condition. Participants’ mean accuracy in the 35° condition (38.18%) was substantially lower than in the 20° condition (50.88%).  相似文献   
236.
Heat and mechanical protection properties of 6 fabric combinations commonly used in firefighters’ protective clothing were assessed before and after different heat treatment. It was shown that after heat exposure, the values obtained were generally lower than in the original state. The mechanical properties of the materials were more affected by heat than by heat protective properties. In 2 cases, degradation started before a visible change in the material could be observed, which might be potentially dangerous for the end user who will not realize the alteration of the material.  相似文献   
237.
This paper presents the use of new technical equipment by young adults (30 years old or younger), and the physical symptoms they have. The paper then analyses how the symptoms are associated with the use of computers and mobile phones, taking into account the background information. The study is based on a survey of 15000 working-age ( 18-65) Finns. The responses (1563) covering young adults’ physical symptoms were analysed. Altogether 53.3% of all young adults had pretty often or more frequently pain, numbness or aches in the neck and 32.2% had aches in the hip and lower back. Women experienced more pain, numbness or aches in the neck (65.0%) than men (34.5%). The use of different computers at leisure quite often had an association with some symptoms in different parts of the body. In addition, exhaustion at work had associations with some physical symptoms. In the future, it is essential to note ergonomic reasons and exhaustion at work when young adults experience pain, numbness or aches.  相似文献   
238.
Aim. Firefighters must meet minimum physical demands. The Norwegian Labour Inspection Authority (NLIA) has approved a standardised treadmill walking test and 3 simple strength tests for smoke divers. The results of the Trondheim test were compared with those of the NLIA tests taking into account possible effects of age, experience level and gender. Methods. Four groups of participants took part in the tests: 19 young experienced firefighters, 24 senior male firefighters and inexperienced applicants, 12 male and 8 female. Results. Oxygen uptake (VO2) at exhaustion rose linearly by the duration of the treadmill test. Time spent on the Trondheim test was closely related to performance time and peak VO2 on the treadmill test. Senior experienced firefighters did not perform better than equally fit young applicants. However, female applicants performed poorer on the Trondheim test than on the treadmill test. Performance on the Trondheim test was not closely related to muscle strength beyond a minimum. Conclusion. Firefighters completing the Trondheim test in under 19 min fit the requirements of the NLIA treadmill test. The Trondheim test can be used as an alternative to the NLIA tests for testing aerobic fitness but not for muscular strength. Women’s result of the Trondheim test were poorer than the results of the NLIA treadmill test, probably because of their lower body mass.  相似文献   
239.
The skin is the part of the human body most vulnerable to ultraviolet (UV) radiation. The spectrum of the negative effects of UV radiation on the skin ranges from acute erythema to carcinogenesis. Between these extreme conditions, there are other common skin lesions, e.g.,photoageing. The aim of this study was to assess the skin for signs of photoageing in a group of 52 men occupationally exposed to natural UV radiation. There were 2 types of examinations: an examination of skin condition (moisture, elasticity, sebum, porosity, smoothness, discolourations and wrinkles) with a device for diagnosing the skin, and a dermatological examination. The results of both examinations revealed a higher percentage of skin characteristics typical for photoageing in outdoor workers compared to the general population.  相似文献   
240.
This article focuses on employee direct participation in occupational health and safety (OHS) management. The article explains what determines employee opportunities to participate in OHS management. The explanatory framework focuses on safety culture and safety management at workplaces. The framework is empirically tested using Estonian cross-sectional, multilevel data of organizations and their employees. The analysis indicates that differences in employee participation in OHS management in the Estonian case could be explained by differences in OHS management practices rather than differences in safety culture. This indicates that throughout the institutional change and shift to the European model of employment relations system, change in management practices has preceded changes in safety culture which according to theoretical argument is supposed to follow culture change.  相似文献   
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