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991.
This study evaluated how urban bus drivers' well-being was affected by technical interventions designed to improve the traffic environment of an urban bus route. Three questionnaires were distributed; 8 drivers at the intervention route (mean age 43 years) and 13 demographically matched comparison drivers (mean age 39 years) participated at all occasions. Field studies at work were conducted twice, with 10 intervention route drivers (mean age 43 years) and 31 comparison drivers (mean age 42 years). The authors hypothesized that during the course of the intervention, the initially elevated indexes of occupational stress in the intervention group would be reduced to levels equivalent to those of the comparison group. The hypothesis was confirmed for perceived workload in the questionnaire, observer-rated job hassles, systolic blood pressure and heart rate at work, and perceived distress after work in the field study. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
992.
Moreland Kevin L.; Eyde Lorraine D.; Robertson Gary J.; Primoff Ernest S.; Most Robert B. 《Canadian Metallurgical Quarterly》1995,50(1):14
The qualifications of test purchasers have been a concern of the American Psychological Association since 1950, when ethical standards for test distribution, on the basis of a 3-level classification of tests, were developed. The standards relied on professional credentials and on occupational titles to screen test purchasers. In response to widespread recognition that credentials and titles were inadequate to screen test purchasers, the Test User Qualifications Working Group used 2 job analysis methods to determine test user competencies. This article describes the results of that research that can be applied to improving testing practices, including (a) 86 test user competencies and 7 factors accounting for much test misuse, (b) a test classification system based on critical incidents of test misuse, and (c) empirically based test purchaser qualification forms. These products are designed to help achieve responsible test use. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Abstract: During the last decade, cumulative trauma disorders have become a major concern both to occupational health and safety professionals and manufacturing industries. This paper will present the development of a knowledge-based system for predicting the potential of developing strain injuries among employees exposed to repetitive and forceful activities. This potential is identified through the use of an expert system incorporating a fuzzy set algorithm. Recommendations for the prevention of the resulting CTDs are then provided by the system. The system executes on a microcomputer platform, and was constructed utilising a commercial object-oriented expert system shell. 相似文献
995.
R. Aravamuthan W.Y. Chen K. Zargarian Gary C. April 《Chemical Engineering Communications》1988,69(1):115-127
A two-stage acid hydrolysis process is currently used in the production of ethanol from hardwoods. In this process, dilute sulfuric acid in water at high pressure and short residence times hydrolyzes the wood and first stage substrate. The chemical action is particularly impeded in the second stage by the presence of acid condensed lignin.
Presulfonation followed by delignification is proposed using a sulfur dioxide/water sulfuric acid/ethanol treatment step in place of the first stage acid hydrolysis step to alleviate this problem.
Results presented include the effects caused by varying treatment time, sulfur dioxide concentration, temperature and ethanol concentration on the degree of delignification, and, on the recovery of C5 and C6 sugars in the hydrolysates. A preliminary economic feasibility analysis is made to determine the impact of improved ethanol yields and lignin by-product values in the production of ethanol from hardwoods. 相似文献
Presulfonation followed by delignification is proposed using a sulfur dioxide/water sulfuric acid/ethanol treatment step in place of the first stage acid hydrolysis step to alleviate this problem.
Results presented include the effects caused by varying treatment time, sulfur dioxide concentration, temperature and ethanol concentration on the degree of delignification, and, on the recovery of C5 and C6 sugars in the hydrolysates. A preliminary economic feasibility analysis is made to determine the impact of improved ethanol yields and lignin by-product values in the production of ethanol from hardwoods. 相似文献
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