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71.
The three-compartment model (3CM) was validated previously for prediction of endurance times by modifying its fatigue and recovery rates. However, endurance times do not typically represent work demands, and it is unknown if the current version of the 3CM is applicable for ergonomics analysis of all occupational tasks. The purpose of this study was to add biological fidelity to the 3CM, and validate the model against a series of submaximal force plateaus. The fatigue and recovery rates were modified to represent graded physiological motor unit characteristics (termed 3CMGMU). In nine experiments of submaximal efforts, the 3CMGMU produced a root-mean squared difference (RMSD) of 4.1 ± 0.5% MVC over experiments with an average strength loss (i.e. fatigue) of 31.0 ± 1.1% MVC. The 3CMGMU model performed poorly for endurance tasks. The 3CMGMU model is an improvement for evaluating submaximal force patterns consisting of intermittent muscle contractions of the hand and forearm.

Practitioner Summary: We modified an existing fatigue model using known physiological properties in order to predict fatigue during nine different submaximal force profiles; consistent with efforts seen in industrial work. We expect this model to be included in digital human modelling software, for the assessment of repetitive work and muscle fatigue in repetitive tasks.

Social Media Summary: The proposed model has applications for estimating task fatigue in proactive ergonomic analyses of complex force patterns using digital human models.  相似文献   

72.
This paper introduces and motivates ADL, a new formal notation for the specification of the temporal and functional behaviour of concurrent processes. ADL is tailored to be directly compatible with the DORIS design method. It combines a graphical Activity State-Machine (ASM) notation and a model-based Activity Functional Behaviour (AFB) notation. The abstract syntax, and static and dynamic semantics for the ASM notation are given, the dynamic semantics being given proof-theoretically in many-sorted logic extended with the RTL ‘occurrence’ relation, Θ, and the ERTL ‘holding’ relation, Φ. ADL is used to specify a small network, and proofs are given of its timeliness and safety properties. Received November 1998 / Accepted in revised form May 2000  相似文献   
73.
Who Are You? The Trade-Off between Information Utility and Privacy   总被引:1,自引:0,他引:1  
There's no doubt that personal information can be valuable to companies. People are willing to give up information about themselves not because they're stupid or because they're being tricked by evil corporations, but because it can sometimes be in their best interests to do so. From this perspective, the important questions are how users can provide or limit access to that information, what benefits they might receive in exchange for a bit of information, and how they perceive the value of those benefits.  相似文献   
74.
Service Science     
This paper is a first exploration of the relationship between service science and Grid computing. Service science is the study of value co-creation interactions among entities, known as service systems. Within the emerging service science community, service is often defined as the application of competences (resources) for the benefit of another. Grid computing is the study of resource sharing among entities, known as virtual organizations, which solve complex business, societal, scientific, and engineering problems. Within the Grid computing community, service is sometimes defined as protocols plus behavior. Both Grid computing and service science are connecting academic, industry, government, and volunteer sector collaborators on a range of projects including eScience, healthcare, environmental sustainability, and more. This paper compares and contrasts the notions of resource, entity, service, interaction, and success criteria for the two areas of study. In conclusion, new areas for collaborative inquiry are proposed.  相似文献   
75.
Brick masons and mason tenders report a high prevalence of work-related musculoskeletal disorders (WMSDs), many of which can be prevented with changes in materials, work equipment or work practices. To explore the use of "best practices" in the masonry industry, NIOSH organized a 2-day meeting of masonry stakeholders. Attendees included 30 industry representatives, 5 health and safety researchers, 4 health/safety specialists, 2 ergonomic consultants, and 2 representatives of state workers' compensation programs. Small groups discussed ergonomic interventions currently utilized in the masonry industry, including factors affecting intervention implementation and ways to promote diffusion of interventions. Meeting participants also identified various barriers to intervention implementation, including business considerations, quality concerns, design issues, supply problems, jobsite conditions and management practices that can slow or limit intervention diffusion. To be successful, future diffusion efforts must not only raise awareness of available solutions but also address these practical concerns.  相似文献   
76.
This research investigates the use of patterns in designing adaptable, flexible hypermedia applications. While patterns are particularly applicable to software design, they can also be used to assist designers of other types of applications. We have developed a method (APHID) that guides a hypermedia creator through the analysis and design process. The method ensures that good design principles are followed, both for the hypermedia application and for the interface that presents the hypermedia application. Our method uses a concept map, constraints, and patterns (instructional and presentation) to support partial automation for creating hypermedia applications. We also present a prototype software system that uses the APHID method to create instructional hypermedia applications semi-automatically. The applications created using APHID are tailored to specific types of learners. We conclude with a claim that this approach is applicable not just to instructional hypermedia, but to the larger problem of generating adaptable interfaces.  相似文献   
77.
78.
Programmable logic designs are presented that achieve exact integration of leaky integrate-and-fire soma and dynamical synapse neuronal models and incorporate spike-time dependent plasticity and axonal delays. Highly accurate numerical performance has been achieved by modifying simpler forward-Euler-based circuitry requiring minimal circuit allocation, which, as we show, behaves equivalently to exact integration. These designs have been implemented and simulated at the behavioral and physical device levels, demonstrating close agreement with both numerical and analytical results. By exploiting finely grained parallelism and single clock cycle numerical iteration, these designs achieve simulation speeds at least five orders of magnitude faster than the nervous system, termed here hyper-real-time operation, when deployed on commercially available field-programmable gate array (FPGA) devices. Taken together, our designs form a programmable logic construction kit of commonly used neuronal model elements that supports the building of large and complex architectures of spiking neuron networks for real-time neuromorphic implementation, neurophysiological interfacing, or efficient parameter space investigations.  相似文献   
79.
Much effort has gone into the recognition of the human right to water. Without doubt, this milestone influences governance and decision making processes at many scales so it is essential now to shift the discussion from the legal and conceptual framework to practice. Along this line, the article proposes a methodology for monitoring access to water in rural areas using the framework of this human right. The practicality of the approach is demonstrated by a case study carried out in Nicaragua. Different criteria of the right to water were included in surveys and structured interviews that were conducted in rural households and water committees, respectively. A discussion analyzes the advantages and challenges of using this framework. Finally, the approach provides elements for policy making that can be used by different stakeholders in the development and human rights sectors.  相似文献   
80.
Sustainable groundwater development must rely on a good understanding of hydrological processes, especially under effects of anthropogenic activities. This paper develops a piecewise analysis based on grey system model for study effects of anthropogenic activities on hydrological processes. The time series of precipitation and spring discharge were segmented into three time periods depending on whether variations are due to climate variation: the predevelopment stage, the transition stage, and the new equilibrium stage. Then we modeled hydrological process of the predevelopment stage and new equilibrium stage by the grey system model. By comparing the model results, we can quantify the effects of human activities on hydrological processes. We applied the model to Liulin Springs China. The results indicated that the hydraulic response time of the spring discharge to precipitation from the predevelopment stage to the new equilibrium stage, ranges from less than 1 year to up to 4 years. The results revealed that human activities slow the groundwater flow. GM (1,N) models of Liulin Springs discharge showed that the driving coefficients of precipitation to the spring discharge decreased from 0.012272 in the predevelopment stage to 0.007753 in the new equilibrium stage, which means that groundwater recharge ability has reduced about 36.82 %. Human activities in Liulin Springs have drastically changed the groundwater system. Piecewise grey system model is a robust method for hydrological process simulation.  相似文献   
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