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921.
We examine how openness interacts with the coordination of consumption–leisure decisions in determining the equilibrium working hours and wage rate when there are leisure externalities (e.g., due to social interactions). The latter are modelled by allowing a worker's marginal utility of leisure to be increasing in the leisure time taken by other workers. Coordination takes the form of internalising the leisure externality and other relevant constraints (e.g., labour demand). The extent of openness is measured by the degree of capital mobility. We find that: coordination lowers equilibrium work hours and raises the wage rate; there is a U-shaped (inverse-U-shaped) relationship between work hours (wages) and the degree of coordination; coordination is welfare improving; and, the gap between the coordinated and uncoordinated work hours (and the corresponding wage rates) is affected by the extent and nature of openness.  相似文献   
922.
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   
923.
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   
924.
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   
925.
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   
926.
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   
927.
This article considers the challenge of extending conventional models of flexibility to hourly jobs that are often structured quite differently than the salaried, professional positions for which flexibility options were originally designed. We argue that the assumptions of job rigidity and overwork motivating existing flexibility options may not be broadly applicable across jobs in the US labor market. We focus specifically on two types of flexibility: (1) working reduced hours and (2) varying work timing. We first review central aspects of the US business and policy contexts that inspire our concerns, and then draw on original analyses from US census data and several examples from our comparative case-study research to explain how conventional flexibility options do not always map well onto hourly jobs, and in certain instances may disadvantage workers by undermining their ability to earn an adequate living. We conclude with a discussion of alternative approaches to implementing flexibility in hourly jobs when hours are scarce and fluctuating rather than long and rigid.  相似文献   
928.
In this article, we attempt to conceptualize the historical development and the governance structure of the transnational organic cotton network from Benin. We aim to discover how the organic cotton production‐consumption network is governed locally and internationally. Existing bodies of literature on international agricultural production networks, in particular the Global Value Chains (GVC) perspective, focus on economic dimensions, but find it difficult to incorporate the sustainability dimension. We favour widening the concept of GVCs beyond economics by acknowledging and including environmental rationalities and the representatives of their interests, not as external elements, but rather as co‐governing or co‐structuring factors (or actors) of sustainable value chains. Our findings reveal that beyond the traditional producer versus buyer dualism, intermediate stakeholders, namely transnational and local environmental NGO networks, are instrumental in the construction, maintenance and transformation of the organic cotton network. It is also apparent that farmers' leaders play an important role in mediating and (re)building trust among organic farmers, though they exert insufficient vertical power in the organic cotton network to control it.  相似文献   
929.
930.
This study examined biological sex differences in the development of mild cognitive impairment (MCI) and probable Alzheimer’s disease (AD) development as predicted by changes in the hippocampus or white matter hyperintensities. A secondary data analysis of the National Alzheimer’s Coordinating Center Uniform Data Set was conducted. We selected samples of participants with normal cognition at baseline who progressed to MCI (n = 483) and those who progressed to probable AD (n = 211) to determine if hippocampal volume or white matter hyperintensities (WMH) at baseline predicted progression to probable AD or MCI and whether the rate of progression differed between men and women. The survival analyses indicated that changes in hippocampal volumes affected the progression to probable AD (HR = 0.535, 95% CI [0.300–0.953]) only among women. White men had an increased rate of progression to AD (HR = 4.396, CI [1.012–19.08]; HR = 4.665, 95% CI [1.072–20.29]) compared to men in other race and ethnic groups. Among women, increases in hippocampal volume ratio led to decreased rates of progressing to MCI (HR = 0.386, 95% CI [0.166–0.901]). Increased WMH among men led to faster progression to MCI (HR = 1.048. 95% CI [1.011–1.086]). Women and men who were older at baseline were more likely to progress to MCI. In addition, results from longitudinal analyses showed that women with a higher CDR global score, older age at baseline, or more disinhibition symptoms experienced higher odds of MCI development. Changes in hippocampal volumes affect the progression to or odds of probable AD (and MCI) more so among women than men, while changes in WMH affected the progression to MCI only among men.  相似文献   
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