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Ergonomic evaluation of visual demands becomes crucial for the operators/users when rapid decision making is needed under extreme time constraint like navigation task of jet aircraft. Research reported here comprises ergonomic evaluation of pilot's vision in a jet aircraft in virtual environment to demonstrate how vision analysis tools of digital human modeling software can be used effectively for such study. Three (03) dynamic digital pilot models, representative of smallest, average and largest Indian pilot population were generated from anthropometric database and interfaced with digital prototype of the cockpit in Jack software for analysis of vision within and outside the cockpit. Vision analysis tools like view cones, eye view windows, blind spot area, obscuration zone, reflection zone etc. were employed during evaluation of visual fields. Vision analysis tool was also used for studying kinematic changes of pilot's body joints during simulated gazing activity. From present study, it can be concluded that vision analysis tool of digital human modeling software was found very effective in evaluation of position and alignment of different displays and controls in the workstation based upon their priorities within the visual fields and anthropometry of the targeted users, long before the development of its physical prototype. 相似文献
154.
Condom Use Trajectories in Adolescence and the Transition to Adulthood: The Role of Mother and Father Support 总被引:1,自引:0,他引:1
Pingel ES Bauermeister JA Elkington KS Fergus S Caldwell CH Zimmerman MA 《Journal of research on adolescence》2012,22(2):350-366
Few studies have investigated how mother and father support differ on predicting youths' sexual risk behavior. We therefore examined the influence of parental support on condom use trajectories and its correlates in a predominantly African American sample [(N=627; 53% female; M = 14.86 years (SD=. 64)] from adolescence to young adulthood. We used hierarchical growth curve modeling to examine the relationship between condom use, substance use, psychological distress and parental support prospectively. We found that consistent condom use decreased over time and was associated negatively with psychological distress and substance use. Furthermore, both maternal and paternal support were associated with more condom use over time. We discuss the implications of our findings for HIV prevention programs. 相似文献
155.
The objective of this study is to reach a better understanding of accidents on Swedish roads involving tractors and to suggest ways of preventing them. In an earlier study we analyzed police-reported fatal accidents and accidents that led to physical injuries from 1992 to 2005. During each year of this period, tractors were involved in 128 traffic accidents on average, an average of 7 people were killed, 44 sustained serious injuries, and 143 sustained slight injuries. The number of fatalities in these tractor accidents was about 1.3% of all deaths in traffic accidents in Sweden. Cars were most often involved in the tractor accidents (58%) and 15% were single vehicle accidents. The mean age of the tractor driver involved was 39.8 years and young drivers (15-24 years) were overrepresented (30%). We are now increasing the data collected with the years 2006-2010 in order to study the changes in the number of accidents. Special attention will be given to the younger drivers and to single vehicle accidents. Based on the results we aim to develop suggestions for reducing road accidents, e.g. including measures for making farm vehicles more visible and improvement of the training provided at driving schools. 相似文献
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Sport for Development has many reported benefits, but quantitative evidence of the impact of these interventions in Low Income Countries remains sparse. A new monitoring and evaluation toolkit was used in a cross-sectional survey at Moving the Goalposts (MTG), a football project aiming to empower young Kenyan women. We wished to determine empirically whether increased membership duration brought increased benefits. MTG selected and translated toolkit items consistent with the organisation's strategic aims. We collected 333 completed questionnaires at 15 sites. Psychometric validation revealed some reliable scales; remaining items were scored separately. Scores were sensitive to differences between members defined by sociodemographic and site characteristics. Bivariate and multiple regression analyses showed that increased membership duration brought increasing benefits across several domains (perceived lifeskills; social life; insights about HIV/AIDS; outcomes related to female empowerment). Improved leadership skills were mainly age-related. Members attending more established sites experienced greater benefits, but members at more and less accessible sites benefitted similarly. Positive thoughts and feelings were related not to membership duration, but to how long a site had been operating. This indicates the importance of creating a positive culture over time. This cross-sectional study provides quantitative evidence for the benefits of Sport for Development initiatives. 相似文献
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目前,环境保护成为全球亟待解决的问题.由于越来越多的地区参与到经济活动中,因而环境保护涉及包括人口稀疏地区在内的各个地区.在多数情况下,人为因素给环境带来了许多负面的影响.
环境问题不仅与整个国家相关,也与各个地区相关,包括俄罗斯的沃洛格达地区. 相似文献