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81.
82.
Vincent Verhaert Hans Druyts Dorien Van Deun Vasileios Exadaktylos Johan Verbraecken Marie Vandekerckhove Bart Haex Jos Vander Sloten 《International Journal of Industrial Ergonomics》2012,42(5):489-498
This study aims at evaluating spinal alignment during sleep by combining personalized human models with mattress indentation measurements. A generic surface model has been developed that can be personalized based on anthropometric parameters derived from silhouette extraction. Shape assessment of the personalized surface models, performed by comparison with 3-D surface scans of the trunk, showed a mean unsigned distance of 9.77 mm between modeled and scanned surface meshes. The surface model is combined with an inner skeleton model, allowing the model to simulate distinct sleep postures. An automatic fitting algorithm sets the appropriate degrees of freedom to position the model on the measured indentation according to the adopted sleep posture. Validation on lateral sleep positions showed good intraclass correlations (0.73–0.88) between estimated and measured angular spinal deformations, indicating that silhouette-derived body shape models provide a valuable tool for the unobtrusive assessment of spinal alignment during sleep.Relevance to industry: A common drawback of the available techniques to assess spinal deformation on bedding systems is that they interfere with the actual sleep process. The current study presents a novel method based on silhouette-derived body shape models in order to estimate spine shape during sleep unobtrusively. 相似文献
83.
This paper examines and ranks restoration alternatives for improving fish habitat by evaluating tradeoffs between fish production and restoration costs. Optimization modelling is used to maximize out‐migrating coho salmon (Oncorhynchus kisutch) from a natal stream and is applied as a case study in California's Shasta River. Restoration activities that alter flow and water temperature conditions are the decision variables in the model and include relocating a major diversion, increasing riparian shading, increasing instream flow, restoring a cool‐water spring and removing a dam. A budget constraint limits total restoration expenditures. This approach combines simple fish population modelling with flow and water quality modelling to explore management strategies and aid decision making. Previous fish habitat optimization research typically uses single restoration strategies, usually by altering reservoir releases or modifying outlet structures. Our method enlarges the solution space to more accurately represent extensive and integrated solutions to fish habitat problems. Results indicate that restoration alternatives can be prioritized by fish habitat improvement and restoration cost. For the Shasta River case study, considerable habitat restoration investments were required before fish productivity increased substantially. This exercise illustrates the potential of ecological optimization for highlighting promising restoration approaches and dismissing poor alternatives. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
84.
Rasmussen CD Jørgensen MB Carneiro IG Flyvholm MA Olesen K Søgaard K Holtermann A 《Ergonomics》2012,55(2):256-264
Worksite health promotion is seldom offered to workers who are low-educated and multi-ethnic, possibly due to an assumption that they are more reluctant to participate. Furthermore, little has been done to promote health at female-dominated workplaces. The main aim of this study was to investigate differences in participation among immigrant and Danish cleaners throughout a 1-year randomised controlled study tailored to cleaners and carried out in predominantly female workplaces. No significant differences in ethnicity were found in consent and participation throughout the 1-year intervention. Dropout was equally distributed among Danish and immigrant cleaners. This study indicates that a worksite health promotion intervention among a female-dominated, high-risk occupation such as cleaning can be equally appealing for Danes and immigrants. PRACTITIONER SUMMARY: This study provides insight about participation of Danish and immigrant cleaners in a worksite health promotion intervention in a predominantly female occupation. For attaining high participation and low dropout in future worksite health promotion interventions among cleaners, the intervention ought to not only target the ethnic background of the workers, but also to be specifically tailored to the job group. 相似文献
85.
Jørgensen MB Faber A Jespersen T Hansen K Ektor-Andersen J Hansen JV Holtermann A Søgaard K 《Ergonomics》2012,55(7):762-772
This study evaluates the implementation of physical coordination training (PCT) and cognitive behavioural training (CBTr) interventions in a randomised controlled trial at nine cleaners' workplaces. Female cleaners (n = 294) were randomised into a PCT, a CBTr or a reference (REF) group. Both 12-week interventions were performed in groups guided by an instructor. Records were kept on intervention dose (adherence) unanticipated events at the work place (context) and quality of intervention delivery (fidelity). Participant adherence was 37% in the PCT and 49% in the CBTr interventions. Optimal implementation was reached by only 6% in PCT and 42% in the CBTr. Analysis of the barriers to successful implementation indicated that the intervention process is sensitive to unanticipated events. In order to succeed in improving the health of high-risk populations such as cleaners and to correctly interpret intervention effects, more research on implementation is needed. Trial registration: ISRCTN96241850. PRACTITIONER SUMMARY: Both physical coordination training and cognitive behavioural training are potential effective workplace interventions among low educated job groups with high physical work demands. However, thorough consideration should be given to feasibility in the design of interventions. The optimal intervention should be tailored to closely match the implementation context and be robust and flexible to minimise susceptibility to changes in work organisation. 相似文献
86.
Questions S. L. Bem's (see record 1983-21087-001) definition of a gender schema and argues that male and female sex-typed individuals do not have equivalent gender schemata. The high-androgynous individuals are the only ones for whom both masculinity and femininity are equally available and who might be properly termed "gender schematic." (6 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
87.
Technological and environmental behavior of sewage sludge ash (SSA) in cement-based materials 总被引:4,自引:0,他引:4
Sewage sludge ash (SSA) is a waste material obtained from the incineration of wastewater sludge. The physical, chemical and mineralogical characteristics of SSA, and the evaluation of its use in cement-based materials, are presented in this paper. Results show that SSA is composed of irregular grains having a high specific surface area and thus leading to a significantly high water demand. A fraction of the ash is rapidly soluble (sulfates, aluminum and silica) and can create new-formed products in presence of lime. SSA induces short delays of cement hydration, probably due to both minor elements of the ash and dilution effect. Compressive strengths of mortars containing 25% and 50% of SSA are always lower than those of reference mortars but it is shown that SSA has a long-term positive effect which might be related to a slight pozzolanic activity. The amount of elements leached from SSA mortars is slightly higher than from the reference mortar without residue but it remains of the same order of magnitude. An extensive literature review was performed in order to compare the residue used in this study with others included in the same category. This analysis highlighted the principal characteristics that must be taken into account to use SSA correctly in cement-based materials. 相似文献
88.
It is not generally appreciated that pseudoxanthoma elasticum (PXE) can be associated with epidermal perforation by elastic fibers. We report an example of this phenomenon. The term "perforating PXE" is suggested and a distinction is made from elastosis perforans serpiginosa (EPS). We believe that most reported cases of coexistence of PXE and EPS are perforating PXE and that the coexistence of EPS has not been clearly demonstrated. 相似文献
89.
Marie A Wright 《Network Security》1998,1998(2):10-13
Many Internet applications use public key technology for security purposes. These applications (i.e. World Wide Web protocols, Internet protocol security, digital signatures, user authentication and E-mail) require a public key infrastructure (PKI) to securely manage public encryption keys for widely distributed users or systems.1 The use of public key technology requires that the user of a public key be confident that the public key belongs to the correct remote subject (i.e. person or system) with which the encryption mechanism will be used.2 This confidence is obtained through the use of public key certificates.2 相似文献
90.
This article provides an overview of the factors that may contribute to the effective term of protection for a pharmaceutical product in the USA––by patent and by FDA market exclusivities, identifies public and commercial sources for collecting relevant patent term and exclusivity data, and provides a strategy for ensuring that the effective term of protection has been calculated accurately. 相似文献