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151.
A broadened version of the perceptual load model was utilized to explore systematically the influence of four variables on driver's behavior: a. levels of load on the road; b. levels of load at the sides of the road; c. event's initial location (on the road vs. at the sides of the road); and d. the presence and size of advertizing billboards. 18 participants participated in two experimental sessions in a driving simulator. One of the sessions contained advertizing billboards and the other session did not. The results indicated that billboards can have a considerable effect on various aspects of driving like the time required responding to a potentially dangerous event or simply the number of accidents occurring during driving, but importantly the effect of billboards on driving was modulated by the levels of perceptual load. 相似文献
152.
153.
Augmented Reality focuses on the enrichment of the user's natural field of view by consistent integration of text, symbols and interactive three-dimensional objects in real time. Placing virtual objects directly into the user's view in a natural context empowers highly dynamic applications. On the other hand, this necessitates deliberate choice of information design and density, in particular for deployment in hazardous environments like military combat scenarios. As the amount of information needed is not foreseeable and strongly depends on the individual mission, an appropriate system must offer adequate adaptation capabilities. The paper presents a prototypical, vehicle-mountable Augmented Reality vision system, designed for enhancing situation awareness in stressful urban warfare scenarios. Tracking, as one of the most crucial challenges for outdoor Augmented Reality, is accomplished by means of a Differential-GPS approach while the type of display to attach can be modified, ranging from ocular displays to standard LCD mini-screens. The overall concept also includes envisioning of own troops (blue forces), for which a multi-sensor tracking approach has been chosen. As a main feature, the system allows switching between different information categories, focusing on friendly, hostile, unidentified or neutral data. Results of an empirical study on the superiority of an in-view navigation cue approach conclude the paper. 相似文献
154.
Research activities to determine the need of recovery time at work were mainly performed in the 1970s and 1980s. Previous studies were largely based on expert opinions or were generated within small and non-representative groups. Often, laboratory experiments were carried out with a low number of subjects. Especially during the last decade, only little additional scientific knowledge was generated on this topic. The very resource intensive development of more detailed results based on the existing level of scientific knowledge is assumed as one reason for this. In general, it seems to be reasonable to continue further research on the knowledge generated in previous studies, but implement larger samples and more representative groups. Besides, according to monotonous manual work, more research is especially needed regarding relative operating forces and operation frequencies taken grip conditions and hand/body position into account. 相似文献
155.
van Geer E Molenbroek J Schreven S deVoogd-Claessen L Toussaint H 《Work (Reading, Mass.)》2012,41(Z1):4025-4030
In competitive swimming, suits have become more important. These suits influence friction, pressure and wave drag. Friction drag is related to the surface properties whereas both pressure and wave drag are greatly influenced by body shape. To find a relationship between the body shape and the drag, the anthropometry of several world class female swimmers wearing different suits was accurately defined using a 3D scanner and traditional measuring methods. The 3D scans delivered more detailed information about the body shape. On the same day the swimmers did performance tests in the water with the tested suits. Afterwards the result of the performance tests and the differences found in body shape was analyzed to determine the deformation caused by a swimsuit and its effect on the swimming performance. Although the amount of data is limited because of the few test subjects, there is an indication that the deformation of the body influences the swimming performance. 相似文献
156.
Upper extremity musculoskeletal symptoms and disorders are common in the working population. The economic and social impact of such disorders is considerable. Long-time, dynamic repetitive exposure of the hand-arm system during manual handling operations (MHO) alone or in combination with static and postural effort are recognised as causes of musculoskeletal symptoms and disorders. The assessment of these manual work tasks is crucial to estimate health risks of exposed employees. For these work tasks, a new method for the assessment of the working conditions was developed and a validation study was performed. The results suggest satisfying criterion validity and moderate objectivity of the KIM-MHO draft 2007. The method was modified and evaluated again. It is planned to release a new version of KIM-MHO in spring 2012. 相似文献
157.
This study investigates how future informatics applications can support and challenge intensive care nurses (ICU nurses) to grow and learn continuously. To this end a research-and-design tool is introduced which is based on a model of the nursing process that starts from the idea that a nurse fulfills three different roles: the role of practitioner (using information immediately to base actions upon), the role of scholar (using information later on to learn from) and the role of human (coping with stress and dealing with emotions). In this paper the focus is on the scholar role. Twenty-eight intensive care staff members from six different hospitals were asked to recount an imposing experience from the perspective of each role. Regarding the scholar role, the participants mentioned 77 learning strategies they adopt for individual as well as organizational learning. Individual learning concerned reflection on former patient cases, reflection on current patient cases to anticipate a change in the patient's condition and reflection on personal behavior and decisions. Organizational learning concerned reflection on former patient cases. Examples of specific strategies were formal team evaluations focused on procedure and understanding the perspective of team members, being present at autopsies, and giving feedback on the nursing skills of colleagues. Based on these strategies design implications are defined for future nursing informatics applications, which will be presented. 相似文献
158.
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
159.
Everson MD Sandoval JM Berson N Crowson M Robinson H 《Journal of child sexual abuse》2012,21(1):72-90
In the absence of photographic or DNA evidence, a credible eyewitness, or perpetrator confession, forensic evaluators in cases of alleged child sexual abuse must rely on psychosocial or "soft" evidence, often requiring substantial professional judgment for case determination. This article offers a three-part rebuttal to Herman's (2009 ) argument that forensic decisions based on psychosocial evidence are fundamentally unreliable and that this conclusion represents settled science. The article also discusses the potentially adverse consequences of Herman's proposed reforms to forensic practice on child protection and prosecution efforts. 相似文献
160.
Visual strain and discomfort may contribute to the generation of work-related musculoskeletal disorders among e.g. computer workers. A positive correlation on a group level between eye-lens accommodation and trapezius muscle activity has been reported. In this study we investigated the possibility of a direct, fast, connection between lens accommodation and trapezius muscles activity. The subjects focused alternately on Near and Far targets, with a mean switch time of 5 s, through four different lenses. The cross-correlation, R(tau) was computed, between the time signals of accommodation and electromyography (EMG) from 23 subjects. In the overall mean R(tau) of 736 curves, a small but significant correlation peak (0.019) with a delay (of the EMG signal) of about 0.3 s, revealed a small common component in the two signals. Among the lenses, the positive lens (3.5 D), showed the highest correlation peak (0.040). The correlation may be caused by a direct "hard-wired" connection between the ciliary and trapezius muscles. But it could also be caused indirectly by the subject's need for a more stable head in a more demanding visual task. The latter is supported by the result that the correlation was the highest in the positive lens condition. The present correlation is however weak and it has probably a low practical importance. 相似文献