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911.
912.
Research has been done on the maximum reach and ingress/egress of upright seats. However, research on recumbent seats and comparisons between recumbent and upright seats is limited. By using an eight-camera Vicon motion capture system and C-motion Visual 3D modeling software, this research compared the ingress/egress joint kinematics and maximal planar reach of an upright seat with a recumbent seat. Mean range of motion and mean peak angle for each ingress/egress task were determined and the values for the upright seat were compared to the values for the recumbent seat. For each reach task, three extreme points were extracted and compared between the upright and recumbent seat. Seat orientation was found to have a statistically significant effect on the range of motion of several joints during the ingress/egress tasks, as well as one of the extreme points during the reaching tasks.  相似文献   
913.
Proper body support plays an import role in the recuperation of our body during sleep. Therefore, this study uses an automatically adapting bedding system that optimises spinal alignment throughout the night by altering the stiffness of eight comfort zones. The aim is to investigate the influence of such a dynamic sleep environment on objective and subjective sleep parameters. The bedding system contains 165 sensors that measure mattress indentation. It also includes eight actuators that control the comfort zones. Based on the measured mattress indentation, body movements and posture changes are detected. Control of spinal alignment is established by fitting personalized human models in the measured indentation. A total of 11 normal sleepers participated in this study. Sleep experiments were performed in a sleep laboratory where subjects slept three nights: a first night for adaptation, a reference night and an active support night (in counterbalanced order). Polysomnographic measurements were recorded during the nights, combined with questionnaires aiming at assessing subjective information. Subjective information on sleep quality, daytime quality and perceived number of awakenings shows significant improvements during the active support (ACS) night. Objective results showed a trend towards increased slow wave sleep. On the other hand, it was noticed that % N1-sleep was significantly increased during ACS night, while % N2-sleep was significantly decreased. No prolonged N1 periods were found during or immediately after steering.  相似文献   
914.
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   
915.
This work is based on the study of pioneering sustainable product development initiatives, and the analysis was guided by the cradle-to-cradle concept, which sees the waste of a given process as raw material for another, just like it happens in nature. Several studies on human factors have focused on factory conditions and workers dealing with product assembly. This research, however, relates more to consumer behavior, product use and end-of-life. The purchase of more environmentally- friendly products, in particular, is heavily influenced by the information made available by the companies. In this scenario, this article discusses three early but notable efforts on green product development, focusing on the disclosure practices adopted by the companies regarding the composition of their products. Research and data collection has focused on the footwear industry, whose products satisfy a basic human need and are ubiquitous worldwide. The use of hazardous materials and chemicals in shoe manufacturing, particularly the use of chromium - a highly toxic element - in addition to toxic solvents and adhesives and non-recyclable synthetic materials can pose serious risks to human health and the environment, even though the consumer usually is not aware of all the relevant characteristics of this kind of product.  相似文献   
916.
The noise caused by the movement of users on their chairs in the work environment may indicate structural weaknesses and risk, and still significantly reduce productivity by increasing employees stress level. By understanding the activities to be developed in a work place one may understand what should be necessary to a good development, thereafter a search for improvement of labor activity with the aim of better use of resources in the operation of product use may be done. The analysis of the incremental variation of noise in professional chairs aims to identify its origin and the time the emission of noise starts during the period of use, its development and the major causative agents. Determining the characteristics of the sound of different materials and adjustments mechanisms of the chair can determine how different materials interact with each other. The measurement of these noises in an acoustic isolated room using directional microphones, if recorded and analyzed properly makes it possible to investigate and orientate to suspect elements in order to propose solutions and identify the quality of other similar chairs. Based on the results recommendations can be established for the orientation of users, managers and people responsible for the acquisition of the products, inducing them to review the employment of materials and the choice of the processes of production. These aspects are not covered in the Brazilian ergonomics norms and standards in the use of chairs.  相似文献   
917.
This study aims to describe how anesthesia teams handle unforeseen events that may affect the patients' health. More precisely, it investigates the mechanisms of decisions made by anesthesia teams to manage unthought-of situations, i.e. situations that have not been foreseen as "possible" ones before their occurrence. An empirical study, based on the analysis of simulated situations, was conducted in a pediatric anesthesia service of a university hospital in France. The results highlighted three ways of managing unthought-of situations (determined management, cautious management and overwhelmed management). They support the hypothesis of a collective cognitive trade-off, whereby teams would behave as virtual operators, with their own collective trade-off between "understanding" and "doing". The discussion of the results questions the assessment criteria, the safety perspectives we adopt and the possible ways to improve the management of unforeseen situations.  相似文献   
918.
Smith TJ 《Work (Reading, Mass.)》2012,41(Z1):1961-1968
This paper reports a comparative study of occupancy and patient care quality in four types of intensive care units in a children's hospital,: an Infant Care Center (ICC), a Medical/Surgical (Med/Surg) unit, a Neonatal Intensive Care Unit (NICU), and a Pediatric Intensive Care Unit (PICU), each featuring a mix of multi-bed and private room (PR) patient care environments. The project is prompted by interest by the project sponsor in a pre-occupancy analysis, before the units are upgraded to exclusive PR designs. Methods comprised, for each unit: (1) observations of ergonomic design features; (2) task activity analyses of job performance of selected staff; and (3) use of a survey to collect perceptions by unit nursing and house staff (HS) of indicators of occupancy and patient care quality. Conclusions: (1) the five most common task activities are interaction with patients, charting, and interaction with equipment, co-workers and family members; (2) job satisfaction, patient care, work environment, job, patient care team interaction, and general occupancy quality rankings by ICC and/or NICU respondents are significantly higher than those by other staff respondents; and (3) ergonomic design shortcomings noted are excess noise, problems with equipment, and work environment, job-related health, and patient care quality issues.  相似文献   
919.
Gerontolinguistic obtains a growing importance with the increase of elderly users due to Demographic Change. Since acceptance and ease of use of supportive systems for elderly, such as "E-Nursing-Assistants", are highly dependent on the age suitable design of readable instructions, an age-appropriate linguistic concept is of high value for usability. There has been only little research on the relevance of foreign words, signal words, textual arrangement, optical accentuation of key terms and temporal iconicity concerning older users. Thus, an efficient design of age suitable manual instructions within a medical context still remains to be done. The objective of this research was to evaluate the relevance of the previously mentioned factors in the context of written instructions. For this, an empirical survey was designed which was given to 45 study participants. The subjects of the experiment were given 4x3 instructions after a pretest questionnaire. The aim was to execute these instructions as correctly and quickly as possible. Furthermore the instructions were rated regarding comprehensibility with a retrospective questionnaire.  相似文献   
920.
Internet-based telemedicine is becoming an effective tool to deliver home-healthcare services and health information on demand, especially in rural areas, where there is often a large elderly population with greater rates of preventable chronic diseases. However, the designs of current interfaces for these internet-based telemedicine systems do not take elderly user characteristics into consideration. This study conducted usability testing on the interface of an internet-based telemedicine system using two different age groups, young adults and older adults. Differences in overall performance and satisfaction between the two groups were identified. Based on these results, a future direction is suggested for the interfaces of Internet-based telemedicine systems.  相似文献   
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