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971.
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   
972.
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   
973.
Needle stick injuries (NSIs) are frequently reported as occupational injuries among health care workers. The health effects of a NSI can be significant when blood-to-blood contact occurs from patient to health care worker. The objective of this study was to evaluate whether the number of NSIs decreased among health care workers at risk in one Dutch academic hospital after introduction of injection needles with safety devices in combination with an interactive workshop. In a cluster three-armed randomized controlled trial, 23 hospital divisions (n=796 health care workers) were randomly assigned to a group that was subjected to the use of a 'safety device plus workshop', to a group that was subjected to a 'workshop only' or to a control group with no intervention. The combined intervention of the introduction of needle safety devices and an interactive workshop led to the highest reduction in the number of self-reported NSIs compared to a workshop alone or no intervention. For practice, the use of relatively simple protective needle safety devices and interactive communication are effective measures for reducing NSI's.  相似文献   
974.
This paper presents the Ergonomic Work Analysis method in a Brazilian Dentist's office. Through the study, the constraints and the strategies in avoiding them were identified. It was found that dentists hardly use the position most indicated by the International Organization for Standardization (ISO) and the Federation Dentaire Internacionale (FDI) for both the patient and the dentist, which is respectively supine and 9 o'clock, due to the limited space and layout. Five types of treatments performed by the professional have been studied. The frequency and duration of actions in these treatments were accounted for and the standard positions adopted were identified. The AET was found to be a very suitable method to grasp the dentist's activity and build a point of view of the profession, which is characterized as: stressful, perfectionist and restrictive. Time management is presented as an important strategy to control the tension arising from performing the treatments.  相似文献   
975.
976.
Sexual abuse of children has been a topic of scientific investigation for the past few decades. Research in this area, however, is rarely initiated, conceptualized, and conducted by victims themselves. Apart from possibly having painted a one-sided picture of sexual abuse, this presumed dominance of nonvictims might also have marginalized victims in a research area central to their lives. This study was conducted by a victims interest group as an effort to meet the need to add victims' perspectives to our current understanding of this topic. The online survey focused on investigating victims' psychosocial impairment, which was found to be extensive. Results indicated that an intact social support system facilitates better health, especially when offered early on.  相似文献   
977.
Urbanization is a pervasive and growing threat to amphibian populations globally. Although the number of studies is increasing, many aspects of basic amphibian biology have not been investigated in urban settings. We reviewed 32 urban studies from North America and quantified the number of species studied and their response to urbanization. We examined existing research on breeding habitats, life-history stages, movement patterns, and habitat use relative to urbanization. We found amphibians as a whole respond negatively to urbanization (69 reported responses were negative, 6 were positive and 35 showed no effect). We caution, however, that many North American species still lack or are associated with conflicting information regarding species-specific responses (e.g., 89 potential responses were unknown). Approximately 40% of all anuran and 14% of caudate species in North America were investigated in the literature; however, the most diverse genera (e.g., Plethodon and Eurycea) were the most understudied likely due to their cryptic terrestrial lifestyles and biases in sampling protocols that assess wetland habitats via call surveys. Research on movement and small scale habitat use was deficient. Adult, juvenile, tadpole, and egg mass life-history stages commonly served as direct measures of species presence and abundance; however, such data do not accurately reflect recruitment into subsequent age classes and population persistence. The lack of data on many North American species may be contributing to poor management of urban amphibian populations and their habitats.  相似文献   
978.
979.
Since the 1990s, ethnic studies and other components of multicultural education have been criticized by neo-conservative and assimilationist scholars who maintain that school diversity initiatives weaken national identity and fail to help students attain the knowledge, attitudes, and skills needed to function effectively in the national mainstream culture. The banning of ethnic studies courses in the Tucson (Arizona) Unified School District in the USA was a widely publicized manifestation of the neo-conservative response to multicultural school initiatives. This article describes neo-conservative critiques of ethnic studies, and argues that ethnic studies is an important component of US history that is required to help students become effective and thoughtful citizens in a democratic nation and global world.  相似文献   
980.
This study of 2,163 adult chronic, non-cancer-pain, long-term opioid therapy patients examines the relationship of depression to functional disability by measuring average pain interference, activity limitation days, and employment status. Those with more depression symptoms compared to those with fewer were more likely to have worse disability on all 3 measures (average pain interference score >5, OR = 5.36, p < .0001; activity limitation days ≥ 30, OR = 4.05, p < .0001; unemployed due to health reasons, OR = 4.06, p < .0001). Depression might play a crucial role in the lives of these patients; identifying and treating depression symptoms in chronic pain patients should be a priority.  相似文献   
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