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131.
This paper describes the results of a summative evaluation conducted to explore the usability and acceptability of an automated telephone-based technology, designed and developed as a screening tool for mental health disorders in the workplace. The system screens employees for symptoms and subsequently provides educational information and referrals to improve mental health and enhance productivity. The qualitative evaluation was a sub-study of a larger randomized controlled trial (RCT). We conducted in-depth interviews with 15 individuals who participated in the RCT and had used the system. A phenomenological theoretical framework was utilized to analyze the narrative data. Results indicated that participants had mostly positive experience with the system and perceived it as a confidential program that allowed them to reflect on their symptoms without inhibition, fear of judgment or embarrassment. We also learned that asking mere questions about mental health symptoms can be a positive, instructive and possibly a restorative experience. There is a likelihood that for many participants, exposure to questions about their emotional and mental distress validated their feelings about their symptoms and was sufficiently compelling to promote help-seeking behavior. This evaluation study demonstrates that computers can be utilized in the workplace as effective screening and educational tools to improve employees’ mental health.  相似文献   
132.
Sexually transmitted infections (STIs) continue to pose a threat to the public health in the United States. Many sexual behaviors increase an individual’s risk of STI contraction. Chief among these are having unprotected sex, having sex with multiple partners, and either paying for sex or having sex for pay. The present study used General Social Survey (GSS) data from 2000, 2002, and 2004 to explore the association between exposure to internet pornography and these STI risk behaviors among adult US males. After controlling for demographic and individual difference covariates, internet pornography consumption was positively associated with having sex with multiple partners, engaging in paid sex, and having had extramarital sex. Internet pornography consumption was unrelated to having unprotected sex. Subsequent GSSs have not asked participants about exposure to internet pornography. As the GSS is the only ongoing, full-probability, national survey assessing social beliefs and behaviors, the present report provides unique insight into the risky sexual behavior patterns of adult male internet pornography consumers in the United States.  相似文献   
133.
《Ergonomics》2012,55(5):736-747
This study examined whether manipulability during smartphone thumb-based touch operations could be predicted by the following robotic manipulability indices: the volume and direction of the ‘manipulability ellipsoid’ (MEd), both of which evaluate the influence of kinematics on manipulability. Limits of the thumb's range of motion were considered in the MEd to improve predictability. Thumb postures at 25 key target locations were measured in 16 subjects. Though there was no correlation between subjective evaluation and the volume of the MEd, high correlation was obtained when motion range limits were taken into account. These limits changed the size of the MEd and improved the accuracy of the manipulability evaluation. Movement directions associated with higher performance could also be predicted. In conclusion, robotic manipulability indices with motion range limits were considered to be useful measures for quantitatively evaluating human hand operations.  相似文献   
134.
This paper presents a semiotic technique as a means of exploring meaning and understanding in interface design and use. This is examined through a study of the interaction between the ‘file’ metaphor and ‘save as’ command metaphor. The behaviour of these (from a functional or computational basis) do not exactly match, or map onto, the meaning of the metaphor. We examine both the denotation of a term to the user, i.e. its literal meaning to that person, and the term's connotations, i.e. any other meanings associated with the term. We suggest that the technique applied is useful in predicting future problems with understanding the use of metaphor at the interface and with designing appropriate signification for human-computer interaction. Variation in connotation was expected but a more fundamental difference in denotation was also uncovered. Moreover, the results clearly demonstrate that consistency in the denotation of a term is critical in achieving a good user understanding of the command.  相似文献   
135.
Control errors often occur in repetitive and monotonous tasks, such as manual assembly tasks. Much research has been done in the area of human error identification; however, most existing systems focus solely on the prediction of errors, not on increasing worker accuracy. The current study examines force responses before, during and after errors in a simulated assembly line task in order to determine an optimal feedback system for error reduction. Confirming previous findings, enhanced movement speed and reduced force occurred before erroneous trials and slowing occurred after erroneous trials. Given the results, we suggest a haptic feedback system which stimulates users to exert increased force levels after completing an erroneous task in order to increase degree of control and re-build worker confidence and thereby reduce overall error rate.  相似文献   
136.
《控制论与系统》2012,43(1):27-58
Abstract

The aim of the paper is to develop new aggregation operators using Bonferroni means, ordered weighted averaging (OWA) operators and some distance measures. We introduce the Bonferroni-Hamming weighted distance (BON-HWD), Bonferroni OWA distance (BON-OWAD), Bonferroni OWA adequacy coefficient (BON-OWAAC) and Bonferroni distances with OWA operators and weighted averages (BON-IWOWAD). The main advantages of using these operators are that they allow the consideration of different aggregations contexts to be considered and multiple comparison between each argument and distance measures in the same formulation. An application is developed using these new algorithms in combination with Pichat algorithm to solve a group decision-making problem. Creative personality is taken as an example for forming creative groups. The results show fuzzy dissimilarity relations in order to establish the maximum similarity subrelations and find groups according to each individual’s creative personality similarities.  相似文献   
137.
The long term monitoring of aquatic ecosystems based on chemical analysis is expensive resulting in a lack of time series data for management purposes thus necessitating the need for new cost effective methodologies. This study developed a fish‐based index of biotic integrity (FIBI) for monitoring environmental conditions in riverine ecosystems within the Lake Victoria Basin, Kenya. The fish fauna in the basin is poorly studied, less diverse and ecologically specialized than the temperate fauna that provided the origins of the Index of Biotic Integrity. Fish samples were collected by electrofishing from 24 sites during baseflow periods in February, March and July 2004. Validation data were collected from 7 sites with varying levels of degradation. Fish samples were identified, counted and grouped into different trophic groups, relative tolerance to pollution, habitat guild and whether exotic or native to riverine environment. Thirty‐three candidate metrics were evaluated for responsiveness to habitat quality and twelve were selected for inclusion in the final index. The index classified 6 of the 7 validation sites according to their levels of degradation. As a bioassessment tool, the index was useful in laying the basis for long‐term monitoring of rivers in the Lake Victoria drainage basin. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
138.
《Ergonomics》2012,55(12):1617-1631
Abstract

Intrinsic thermal clothing insulation and surface air insulation were measured on human subjects by the use of indirect calorimetry. Four male clothing ensembles (0-1-1 -8 clo) and three female clothing ensembles (0-2-1-2 clo) were investigated. Using the standing position as a reference, the influence of sitting, bicycling (40r.p.m., 20 W), walking (3-75 km hour?1) and of light packing work on the thermal insulation was studied. The influence of an air velocity of 11ms?1 on thermal insulation during the standing and walking conditions was investigated. The results showed that: (i) intrinsic clothing insulation was maximal in the standing position. It was reduced by 8-18% in the seated position and by 30-50% during bicycling and walking. An air velocity of 11ms?1 did not influence the intrinsic clothing insulation during walking, but decreased it by 18% in the standing position; (ii) surface air insulation varied with activity and air velocity, but not with clothing. It was increased by up to 25% in the seated position, reduced by 7-26% during bicycling and by 30-50% during walking. An air velocity of 11 ms-1 reduced the surface air insulation by 50% in the standing position and 30% during walking.  相似文献   
139.
R Pak  N Fink  M Price  B Bass  L Sturre 《Ergonomics》2012,55(9):1059-1072
This study examined the use of deliberately anthropomorphic automation on younger and older adults' trust, dependence and performance on a diabetes decision-making task. Research with anthropomorphic interface agents has shown mixed effects in judgments of preferences but has rarely examined effects on performance. Meanwhile, research in automation has shown some forms of anthropomorphism (e.g. etiquette) have effects on trust and dependence on automation. Participants answered diabetes questions with no-aid, a non-anthropomorphic aid or an anthropomorphised aid. Trust and dependence in the aid was measured. A minimally anthropomorphic aide primarily affected younger adults' trust in the aid. Dependence, however, for both age groups was influenced by the anthropomorphic aid. Automation that deliberately embodies person-like characteristics can influence trust and dependence on reasonably reliable automation. However, further research is necessary to better understand the specific aspects of the aid that affect different age groups. Automation that embodies human-like characteristics may be useful in situations where there is under-utilisation of reasonably reliable aids by enhancing trust and dependence in that aid. Practitioner Summary: The design of decision-support aids on consumer devices (e.g. smartphones) may influence the level of trust that users place in that system and their amount of use. This study is the first step in articulating how the design of aids may influence user's trust and use of such systems.  相似文献   
140.
《Ergonomics》2012,55(8):1195-1218
The manufacturing sector in the US is challenged by high health care costs and shortage of qualified workers, which are largely attributed to the degree of fit between the worker and work environment. In this regard, a healthy worker–work environment interface is a necessary and sufficient condition for the containment of health care costs and the retaining/attraction of highly qualified knowledge workers and should be based on the principles of optimum physical, cognitive and emotional health for the workers. In prior research, the Work Compatibility Improvement Framework (WCIF) was introduced as a vehicle to address these issues and was defined as the identification, improvement and maintenance of the well-being characteristics of the workforce and its interaction with the work environment through the application of engineering, medicine, management and human sciences methodologies, technologies and best practices. This paper advances WCIF by examining its applications in manufacturing with regard to the evaluation of working conditions impacting musculoskeletal/stress outcome measures. A study was conducted in a machining department of a bag packaging manufacturer in the Midwest of the United States. The work tasks were planned and executed with regard to the following aims: (1) to compute work compatibility as a function of work demands and energisers; (2) to establish whether the prevalence of musculoskeletal/stress disorders increases with a decrease in the quality of worker–work environment interface in terms of work compatibility level and other work factors such as shift and job category. A major finding is that a ‘poor’ work environment (a function of all work domains) results in musculoskeletal/stress disorders that are 105% and 67% higher than those for a ‘good’ work environment. The evening shift exhibited the poorest compatibility followed by the night shift relative to the day shift. Application of the work compatibility approach demonstrated the detection of non-added value work. It is essential to evaluate the various domains of worker–work environment interface to uncover the root causes that tend to sub-optimise the physical/cognitive/emotional health of the workforce. The WCIF was used to uncover the non-value added effort in the work process. These findings will have major implications for developing and implementing customised design interventions with the aim to maximise the benefit and reduce the cost of employees in a manufacturing enterprise. The study findings suggest that the WCIF should be pursued as a potential strategic tool for optimising human performance in an enterprise to create healthy workplaces.  相似文献   
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