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排序方式: 共有470条查询结果,搜索用时 693 毫秒
91.
Lee Skrypchuk Pat Langdon Ben D. Sawyer Alex Mouzakitis P. John Clarkson 《Theoretical Issues in Ergonomics Science》2019,20(2):105-128
In the driving environment, competition exists between Driving Related Activities (DRAs) and Non-Driving Related Activities (NDRAs). This is a source of inattention and human error. Continual proliferation of in-vehicle information systems (IVIS) presents drivers with opportunities for distraction. Drivers simultaneously manage DRAs alongside unrelated but cognitively demanding NDRAs. Vehicle designers need ways of understanding human capability in such situations to provide solutions that accommodate these conflicting demands. This paper proposes a framework intended to address such challenges, rooted in the widely accepted construct of Situation Awareness (SA). However, SA theory does not presently accommodate disparate unrelated goal-driven tasks performed in parallel. This framework reconciles the present reality of drivers simultaneously devoting cognitive resources to attain SA for multiple activities by proposing a separate body of knowledge for each active goal. Additionally, the process of achieving SA is expanded to incorporate this concurrent development of separate bodies of goal-directed knowledge. The advantage of reconceptualising SA for driving allows consideration of interface design which minimises the impact of competing activities. The aim is a framework facilitating creation of IVIS that help drivers succeed in multi-goal multitasking situations. Implications of the proposed framework for theory, design and industry-driven automotive safety efforts are discussed. 相似文献
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Glossopharyngeal neuralgia is a rare and often controversial cause for odynophagia and otalgia. The otolaryngologist, head and neck surgeon may be the primary physician called upon to diagnose and treat this entity. In this study, vascular decompression, or more specifically, elimination of contact between the ninth cranial nerve and the posterior inferior cerebellar artery, was employed as treatment in three patients. All achieved relief of their symptoms with this intervention. A review of the neurosurgical literature and the experience with vascular decompression in trigeminal neuralgia, hemifacial spasm, and glossopharyngeal neuralgia is presented. The authors conclude that vascular decompression is effective in carefully selected patients, and the role of the skull base surgeon in managing this problem is expanding. 相似文献
94.
The problem of acid deposition and its effects on the environment is receiving increasing attention in North America and Europe. The interaction between
seasonal snowcovers and deposited pollutants is of particular importance because a snowpack accumulates and stores pollutants which can ultimately be released in a rapid pulse with the first melt water in the springtime. As a direct result of an impurity pulse, water quality degrades with deleterious effects on the local environment and aquatic biological species. The timing and severity of an inpurity pulse is dependent upon the redistribution of pollutants in a snowpack which is attributed to a process known as temperature gradient metamorphism.
This work investigates the influence of geometry, density and temperature on the coupled heat and mass transport in idealized, two dimensional ice lattice cells. Mass flux, concentration and temperature distributions, as well as effective diffusion coefficients and thermal conductivities are presented as functions of temperature, geometry, and density. A finite element model of the coupled, heat and mass transport is used to analyze the problem on a microscopic scale in two dimensions. Deforming meshes are used to simulate the growth/decay process which occurs over time in an ice lattice pore. 相似文献
seasonal snowcovers and deposited pollutants is of particular importance because a snowpack accumulates and stores pollutants which can ultimately be released in a rapid pulse with the first melt water in the springtime. As a direct result of an impurity pulse, water quality degrades with deleterious effects on the local environment and aquatic biological species. The timing and severity of an inpurity pulse is dependent upon the redistribution of pollutants in a snowpack which is attributed to a process known as temperature gradient metamorphism.
This work investigates the influence of geometry, density and temperature on the coupled heat and mass transport in idealized, two dimensional ice lattice cells. Mass flux, concentration and temperature distributions, as well as effective diffusion coefficients and thermal conductivities are presented as functions of temperature, geometry, and density. A finite element model of the coupled, heat and mass transport is used to analyze the problem on a microscopic scale in two dimensions. Deforming meshes are used to simulate the growth/decay process which occurs over time in an ice lattice pore. 相似文献
95.
Richards Todd; Berninger Virginia; Winn William; Stock Pat; Wagner Richard; Muse Andrea; Maravilla Kenneth 《Canadian Metallurgical Quarterly》2007,21(6):732
Children without dyslexia (n=10) received nonphonological treatment, and those with dyslexia received phonological (n=11) or nonphonological (n=9) treatment. Before and after treatment they performed aural repeat, visual decode, and aural match pseudoword tasks during functional MRI scanning that separated stimulus input from response production. Group map analysis indicated that children with dyslexia overactivated compared with good readers during the aural-repeat/aural-match contrast in bilateral frontal (Brodmann's area [BA] 3, 4, 5, 6, 9), left parietal (BA 2, 3), left temporal (BA 38), and right temporal (BA 20, 21, 37) regions (stimulus input) and underactivated in right frontal (BA 24, 32) and right insula (BA 48) regions (response production); they underactivated in BA 19/V5 during the visual-decode/aural-match contrast (response production). Individual brain analysis for children with dyslexia revealed that during the aural-repeat/aural-match contrast (stimulus input), phonological treatment decreased and normalized activation in left supramarginal gyrus and postcentral gyrus. Nonphonological treatment increased and normalized activation during the visual-decode/aural-match contrast (response production) in BA19/V5 and changed activation in the same direction as good readers during aural-repeat/aural-match contrast (stimulus input) in left postcentral gyrus. The significance of the findings for competing theories of dyslexia is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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98.
Winfield O. Salter Chairman/Animateur 《Tunnelling and Underground Space Technology incorporating Trenchless Technology Research》1992,7(1)
This report summarizes two recommendations prepared by the International Tunnelling Association Working Group on Contratual Sharing of Risks. The recommendations have been officially approved by the ITA General Assembly. 相似文献
99.
The free vibration of a long thick laminated conical tube is studied in this paper with a beam-type model. Taken as a beam, the tube is divided into elements by cross-sections. Each cross-section is a node. In the beam-type model, the nodal forces are assumed to be uniformly distributed along the middle circle, which is the intersection of the cross-section with the middle surface of the tube. The nodal torsional moment is assumed to be produced by a uniformly distributed tangential force along the middle circle. The nodal bending moments are assumed to be produced by sinusoidally distributed axial forces along the middle circle. Three nodal displacements and three nodal rotations corresponding to these nodal forces and moments, respectively, are determined by the energy principle and the assumed deformation pattern. Thus, in the beam-type model, there are only six degrees of freedom at each node. The stiffness matrix in terms of these nodal degrees of freedom is derived from a thick-shell theory together with a semi-analytical method. Based on the stiffness matrix, the frequencies of free vibration are calculated. The numerical results are checked by experimental measurements with good agreement. 相似文献
100.
Extending the Unified Modeling Language for ontology development 总被引:3,自引:0,他引:3
Kenneth Baclawski Mieczyslaw K. Kokar Paul A. Kogut Lewis Hart Jeffrey Smith Jerzy Letkowski Pat Emery 《Software and Systems Modeling》2002,1(2):142-156
There is rapidly growing momentum for web enabled agents that reason about and dynamically integrate the appropriate knowledge
and services at run-time. The dynamic integration of knowledge and services depends on the existence of explicit declarative
semantic models (ontologies). We have been building tools for ontology development based on the Unified Modeling Language
(UML). This allows the many mature UML tools, models and expertise to be applied to knowledge representation systems, not
only for visualizing complex ontologies but also for managing the ontology development process. UML has many features, such
as profiles, global modularity and extension mechanisms that are not generally available in most ontology languages. However,
ontology languages have some features that UML does not support. Our paper identifies the similarities and differences (with
examples) between UML and the ontology languages RDF and DAML+OIL. To reconcile these differences, we propose a modification
to the UML metamodel to address some of the most problematic differences. One of these is the ontological concept variously
called a property, relation or predicate. This notion corresponds to the UML concepts of association and attribute. In ontology
languages properties are first-class modeling elements, but UML associations and attributes are not first-class. Our proposal
is backward-compatible with existing UML models while enhancing its viability for ontology modeling. While we have focused
on RDF and DAML+OIL in our research and development activities, the same issues apply to many of the knowledge representation
languages. This is especially the case for semantic network and concept graph approaches to knowledge representations.
Initial sbmission: 16 February 2002 / Revised submission: 15 October 2002 Published online: 2 December 2002 相似文献