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221.
Jackhammer manufacturers have recently developed lightweight (45-60 lbs) jackhammers intended to reduce the required lifting and pushing forces during operation. However, the vibration characteristics of the lightweight jackhammers and their effect on muscle activity are currently unknown. The objective of this study was to compare the measured vibration and muscle activity between: (i) conventional (90 lb) and light weight (60 lb) jackhammers, (ii) different pavement type/thickness combinations, and (iii) pneumatic and hydraulic jackhammers. Five jackhammers were tested on 4 and 6 inch thick asphalt and concrete pavements by four experienced operators. Analysis of the results revealed that both weight classes averaged 9.7 m/s(2) at the 20 Hz weighted 1/3 octave band frequency, and the TLV of daily exposure for either weight class of jackhammer was less than 1.5 hours/per day. There was an approximately 33% difference in vibration measured on the hand of the operators due to pavement thickness, 30% due pavement type, and no difference due to power source. Conventional jackhammers overall produced higher muscle activity than lightweight jackhammers. Although selection of the correct jackhammer for the job involves many factors including pavement type and thickness, the results of this research can be used to assist in selecting the appropriate jackhammer. 相似文献
222.
Based on a system-theoretic discussion of sustainability, this paper aims to develop a conceptual model of a sustainable work system which is consistent with the definition of ergonomics by the IEA in 2000 (but also with earlier definitions) as well as with the triple bottom line understanding of sustainable development - comprising the management of human, social, ecological and economic capital in a balanced manner. 相似文献
223.
Protecting and conserving environmental resources is a global concern. Over the past decade, a number of certification processes have emerged to help designers and operators of buildings assess the potential impact of a building on the environment. Certifications such as the Leadership in Energy and Environmental Design (LEED) consider the environmental impact through the lifecycle of a building, but may not be considering the people that construct and utilize it. It is important to remember the human factor. Considering the human factor throughout the lifecycle is crucial to ensure individuals are protected during construction and in operation in the built environment. The paper highlights how ergonomics can be integrated into the life cycle of a building to promote sustainability goals for both the human factor and the environment. A case study approach will be used to illustrate how ergonomics was integrated into a LEED renovation and expanded into its daily operations on a large university campus.. 相似文献
224.
In the future the air traffic will rise--the workload of the controllers will do the same. In the BMWi research project, one of the tasks is, how to ensure safe air traffic, and a reasonable workload for the air traffic controllers. In this project it was the goal to find ways how to reduce the workload (and stress) for the controllers to allow safe air traffic, esp. at huge hub-airports by implementing augmented reality visualization and interaction. 相似文献
225.
Haslbeck A Schubert E Onnasch L Hüttig G Bubb H Bengler K 《Work (Reading, Mass.)》2012,41(Z1):178-183
This paper describes an experimental study investigating pilots' manual flying skills. In today's line oriented flight training, basic flying skills are neglected frequently. So, the study examines the manual flying skills of commercial airline pilots under the influence of several performance shaping factors like training, practice or fatigue in a landing scenario. The landing phase shows a disproportionate high percentage of aircraft accidents and it is typically flown by hand. The study is to be undertaken with randomly selected pilots in a full motion flight simulator to ensure a high validity of the results. 相似文献
226.
Ergonomics, usability and user-centered design are terms that are well known among designers. Yet, products often seem to fail to meet the users' needs, resulting in a gap between expected and experienced usability. To understand the possible causes of this gap the actions taken by the designer during the design process are studied in this paper. This can show whether and how certain actions influence the user-friendliness of the design products. The aim of this research was to understand whether ergonomic principles and methods are included in the design process, whether users are involved in this process and whether the experience of the designer (in ergonomics/user involvement) has an effect on the end product usability. In this study the design processes of 151 tangible products of students in design were analyzed. It showed that in 75% of the cases some ergonomic principles were applied. User involvement was performed in only 1/3 of the design cases. Hardly any correlation was found between the designers' experience in ergonomic principles and the way they applied it and no correlations were found between the designers' experience in user involvement and the users' involvement in the design process. 相似文献
227.
Mother-child communication about sexual abuse prevention 总被引:1,自引:1,他引:0
Two hundred and twelve Australian mothers completed an online survey examining features of mother-child communication about child sexual abuse prevention. Two-thirds (67.5%) of respondents had discussed child sexual abuse prevention with their children, with proportions varying according to age range (highest for mothers with children aged 5-12 years) and only-child status (lowest for mothers of only children). The number of topics discussed with their children differed according to child gender (greater number of topics discussed by mothers with both girls and boys) and age range (greater number of topics discussed by mothers with children aged 5-12 years). These findings provide new insights into mother-child communication about child sexual abuse prevention. 相似文献
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Winship K 《Journal of evidence-based social work》2012,9(1-2):19-26
Despite access to a comprehensive administrative database that would allow for timely data retrieval and utilization, regular use of data to inform service provision remained infrequent at one children and family services agency. To address this issue, a research and evaluation manager was hired to facilitate regular data use and evidence-informed service provision. This led to a shift in agency culture that moved from viewing data collection as a burden and threat, to now valuing data as a powerful tool for improving programs and outcomes for children and families. This case study presents the experiences of this agency, describing the process by which the research and evaluation manager was hired, how data are now used by the agency, significant changes resulting from the agency's new data use practices, and perspectives of the evaluator and staff on data use and changes in agency culture. 相似文献