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101.
Workplace studies have made a major contribution to the field of CSCW, drawing attention to subtle practices that enable effective collaboration. However, workplace studies typically focus on a single setting, making it difficult to assess the generalisability of the findings. Through a multi-site workplace study, we explore a specific collaborative process, that of the handover which occurs when a patient is transferred from one hospital or ward to another. The study demonstrates that the term ??handover?? captures a variety of collaborative practices that vary in both their form and content, reflecting aspects of the setting in which they occur. Multi-site workplace studies are shown to be essential for CSCW, not only generating findings that have relevance beyond a single setting but also focusing attention on aspects of work practice that may otherwise go unnoticed.  相似文献   
102.
Purpose: About two million new cases of leishmaniasis with 50 000 associated deaths occur worldwide each year. Promastigotes of the causative Leishmania spp. develop from the procyclic stage to the highly virulent metacyclic stage within the sand fly vector. We hypothesized that proteins important for promastigote virulence might be uniquely represented in the plasma membrane of metacyclic, but not procyclic, promastigotes. Experimental design: Procyclic (logarithmic) promastigotes and purified metacyclic promastigotes from stationary phase cultures of Leishmania chagasi were used to prepare membrane preparations either by surface biotinylation‐streptavidin affinity separation or by octyl glucoside detergent extraction. Results: These membrane fractions were enriched over 130‐ and 250‐fold, respectively, as estimated by Western blotting for the plasma membrane's major surface protease. Hundreds or dozens of proteins were identified by LC‐MS/MS in the surface biotinylation or detergent extraction, respectively. Confocal microscopy suggested the difference between the lists was due to the fact that proteins localized both on the surface membrane and within the flagellar pocket were accessible to surface biotinylation, whereas only proteins on the membrane were obtained by detergent extraction. Using detergent extraction, we found different proteins were present in membranes of the procyclic stage compared to metacyclic stage promastigotes. Several dozen were stage specific. Conclusions and clinical relevance: These data provide a foundation for identifying virulence factors in the plasma membranes of Leishmania spp. promastigotes during metacyclogenesis.  相似文献   
103.
A Survey of UAS Technologies for Command, Control, and Communication (C3)   总被引:1,自引:0,他引:1  
The integration of unmanned aircraft systems (UAS) into the National Airspace System (NAS) presents many challenges including airworthiness certification. As an alternative to the time consuming process of modifying the Federal Aviation Regulations (FARs), guidance materials may be generated that apply existing airworthiness regulations toward UAS. This paper discusses research to assist in the development of such guidance material. The results of a technology survey of command, control, and communication (C3) technologies for UAS are presented. Technologies supporting both line-of-sight and beyond line-of-sight UAS operations are examined. For each, data link technologies, flight control, and air traffic control (ATC) coordination are considered. Existing protocols and standards for UAS and aircraft communication technologies are discussed. Finally, future work toward developing the guidance material is discussed.  相似文献   
104.
On the basis of media hype alone, you might conclude that biometric passwords will soon replace their alphanumeric counterparts with versions that cannot be stolen, forgotten, lost, or given to another person. But what if the actual performance of these systems falls short of the estimates? The authors designed this article to provide sufficient information to know what questions to ask when evaluating a biometric system, and to assist in determining whether performance levels meet the requirements of an application. For example, a low-performance biometric is probably sufficient for reducing-as opposed to eliminating-fraud. Likewise, completely replacing an existing security system with a biometric-based one may require a high-performance biometric system, or the required performance may be beyond what current technology can provide. Of the biometrics that give the user some control over data acquisition, voice, face, and fingerprint systems have undergone the most study and testing-and therefore occupy the bulk of this discussion. This article also covers the tools and techniques of biometric testing  相似文献   
105.
Comparing the performance of distance learning and on-campus students is a well-studied problem. Results have shown that distance learners can perform as well or better than on-campus students. Few studies, however, have explored how or why traditional on-campus students utilize the technology intended for distance learners. Many universities and corporations provide educational and training content simultaneously to both face-to-face and distance students. Thus, exploring how instructional technology typically designed for distance learning students could benefit traditional students is important to our understanding of present and future learning environments. To this end, a pilot study was undertaken that explored how graduate students – primarily business majors – adopted and used video-streaming technology for a one semester course on Knowledge Management Tools and Techniques. Results indicated that age, previous use of the technology, need for interaction and Internet connectivity all influenced the decisions of the subjects to adopt the technology. Two-thirds of the subjects used the technology, with a self-reported estimate of procuring 16% of the course content asynchronously. Most used video streaming for convenience reasons and to review class material.  相似文献   
106.
Two or more parties typically establish a business relationship using a contract, but a large gap still exists between the provisions of contracts produced by lawyers and the details of computer security and performance addressed by technologists. Some contractual clauses address legal issues that technology can manage as well - the TrustCoM framework offers a paradigm for automating these clauses as technical operations. If a business relationship forms across a service-oriented architecture, the parties involved often manage their collaboration as a virtual organization (VO). In TrustCoM, agreements are the key means of steering VO collaborations and mitigating the risks inherent in integrating processes and resources across organizational boundaries.  相似文献   
107.
Sheep shearers are known to work in sustained flexed postures and have a high prevalence of low back pain (LBP). As sustained posture and spinal movement asymmetry under substantial loads are known risk factors for back injury our aim was to describe the 3D spinal movement of shearers while working. We hypothesised that thoraco-lumbar and lumbo-sacral movement would be tri-axial, asymmetric, and task specific. Sufficient retro-reflective markers were placed on the trunk of 12 shearers to define thoraco-lumbar and lumbo-sacral 3D motion during three tasks. Thoraco-lumbar movement consistently involved flexion, left lateral flexion, and right rotation. Lumbo-sacral movement consistently involved right lateral flexion in flexion with minimal rotation. Shearers therefore work in sustained spinal flexion where concurrent, asymmetric spinal movements into both lateral flexion and rotation occur. These asymmetric movements combined with repetitive loading may be risk factors leading to the high incidence of LBP in this occupational group.  相似文献   
108.
Wilson GF  Russell CA 《Human factors》2007,49(6):1005-1018
OBJECTIVE: We show that psychophysiologically driven real-time adaptive aiding significantly enhances performance in a complex aviation task. A further goal was to assess the importance of individual operator capabilities when providing adaptive aiding. BACKGROUND: Psychophysiological measures are useful for monitoring cognitive workload in laboratory and real-world settings. They can be recorded without intruding into task performance and can be analyzed in real time, making them candidates for providing operator functional state estimates. These estimates could be used to determine if and when system intervention should be provided to assist the operator to improve system performance. METHODS: Adaptive automation was implemented while operators performed an uninhabited aerial vehicle task. Psychophysiological data were collected and an artificial neural network was used to detect periods of high and low mental workload in real time. The high-difficulty task levels used to initiate the adaptive automation were determined separately for each operator, and a group-derived mean difficulty level was also used. RESULTS: Psychophysiologically determined aiding significantly improved performance when compared with the no-aiding conditions. Improvement was greater when adaptive aiding was provided based on individualized criteria rather than on group-derived criteria. The improvements were significantly greater than when the aiding was randomly provided. CONCLUSION: These results show that psychophysiologically determined operator functional state assessment in real time led to performance improvement when included in closed loop adaptive automation with a complex task. APPLICATION: Potential future applications of this research include enhanced workstations using adaptive aiding that would be driven by operator functional state.  相似文献   
109.
Experience with the growing number of large-scale and long-term case-based reasoning (CBR) applications has led to increasing recognition of the importance of maintaining existing CBR systems. Recent research has focused on case-base maintenance (CBM), addressing such issues as maintaining consistency, preserving competence, and controlling case-base growth. A set of dimensions for case-base maintenance, proposed by Leake and Wilson, provides a framework for understanding and expanding CBM research. However, it also has been recognized that other knowledge containers can be equally important maintenance targets. Multiple researchers have addressed pieces of this more general maintenance problem, considering such issues as how to refine similarity criteria and adaptation knowledge. As with case-base maintenance, a framework of dimensions for characterizing more general maintenance activity, within and across knowledge containers, is desirable to unify and understand the state of the art, as well as to suggest new avenues of exploration by identifying points along the dimensions that have not yet been studied. This article presents such a framework by (1) refining and updating the earlier framework of dimensions for case-base maintenance, (2) applying the refined dimensions to the entire range of knowledge containers, and (3) extending the theory to include coordinated cross-container maintenance. The result is a framework for understanding the general problem of case-based reasoner maintenance (CBRM). Taking the new framework as a starting point, the article explores key issues for future CBRM research.  相似文献   
110.
We analyze generalization in XCSF and introduce three improvements. We begin by showing that the types of generalizations evolved by XCSF can be influenced by the input range. To explain these results we present a theoretical analysis of the convergence of classifier weights in XCSF which highlights a broader issue. In XCSF, because of the mathematical properties of the Widrow-Hoff update, the convergence of classifier weights in a given subspace can be slow when the spread of the eigenvalues of the autocorrelation matrix associated with each classifier is large. As a major consequence, the system's accuracy pressure may act before classifier weights are adequately updated, so that XCSF may evolve piecewise constant approximations, instead of the intended, and more efficient, piecewise linear ones. We propose three different ways to update classifier weights in XCSF so as to increase the generalization capabilities of XCSF: one based on a condition-based normalization of the inputs, one based on linear least squares, and one based on the recursive version of linear least squares. Through a series of experiments we show that while all three approaches significantly improve XCSF, least squares approaches appear to be best performing and most robust. Finally we show how XCSF can be extended to include polynomial approximations.  相似文献   
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