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Bengtsson P  Johansson CR 《Ergonomics》2002,45(13):910-921
Pictorial visualization is expected to facilitate communication between industrial professionals when planning working environments and production systems. This hypothesis was investigated by studying how 24 participants including managers, supervisors, machine operators, and occupational health and safety officials, judged three types of computer animated visualization varying in dimensional view (scale and scope of a production line): shop floor view/survey of shop floor; production unit view/semi-survey of production unit; and workplace view/close-up of workplace, in relation to a set of planning issues. The participants participated in a controlled 2-day planning workshop, redesigning a fictitious manufacturing process by means of computer graphics, and then responded to a questionnaire. It can be concluded that shop floor view as well as production unit view are significant for survey planning issues, while all 3-dimensional views are significant for close-up planning issues. Analogously, all dimensional views are significant for technocentric planning issues, whereas only the workplace view is valuable for anthropocentric planning issues.  相似文献   
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Attempted to determine the relation between changes in heart rate (HR) and averaged evoked potentials. 16 male undergraduates with variable HRs received 50 flashes of light during fast heart beats, 50 during slow heart beats, and 50 during midrange HR level. Evoked responses were recorded from the scalp overlying the right and left occipital lobes. HR, respiration, eye movements, and cephalic blood flow were also recorded. Results indicate that spontaneous changes in HR were related to changes in visual evoked responses and that this relation differed for the cerebral hemispheres. Cephalic pulse amplitude was largest following slow heart beats and smallest following fast heart beats, which suggests that changes in HR are related to changes in cerebrovascular as well as electrocortical activity. Results are discussed in terms of formulations derived from behavioral studies regarding the relation between cardiovascular activity and attentional processes. (54 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Abstract— A low‐temperature amorphous‐silicon (a‐Si:H) thin‐film‐transistor (TFT) backplane technology for high‐information‐content flexible displays has been developed. Backplanes were integrated with frontplane technologies to produce high‐performance active‐matrix reflective electrophoretic ink, reflective cholesteric liquid crystal and emissive OLED flexible‐display technology demonstrators (TDs). Backplanes up to 4 in. on the diagonal have been fabricated on a 6‐in. wafer‐scale pilot line. The critical steps in the evolution of backplane technology, from qualification of baseline low‐temperature (180°C) a‐Si:H process on the 6‐in. line with rigid substrates, to transferring the process to flexible plastic and flexible stainless‐steel substrates, to form factor scale‐up of the TFT arrays, and finally manufacturing scale‐up to a Gen 2 (370 × 470 mm) display‐scale pilot line, will be reviewed.  相似文献   
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A growing movement in the United States and around the world involves promoting the advantages of conducting an eyewitness lineup in a sequential manner. We conducted a large study (N = 2,529) that included 24 comparisons of sequential versus simultaneous lineups. A liberal statistical criterion revealed only 2 significant sequential lineup advantages and 3 significant simultaneous advantages. Both sequential advantages occurred when the good photograph of the guilty suspect or either innocent suspect was in the fifth position in the sequential lineup; all 3 simultaneous advantages occurred when the poorer quality photograph of the guilty suspect or either innocent suspect was in the second position. Adjusting the statistical criterion to control for the multiple tests (.05/24) revealed no significant sequential advantages. Moreover, despite finding more conservative overall choosing for the sequential lineup, no support was found for the proposal that a sequential advantage was due to that conservative criterion shift. Unless lineups with particular characteristics predominate in the real world, there appears to be no strong preference for conducting lineups in either a sequential or a simultaneous manner. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Regarding the improvement of current quantized Hall resistance (QHR) standards, one promising avenue is the growth of homogeneous monolayer epitaxial graphene (EG). A clean and simple process is used to produce large, precise areas of EG. Properties like the surface conductivity and dielectric loss tangent remain unstable when EG is exposed to air due to doping from molecular adsorption. Experimental results are reported on the extraction of the surface conductivity and dielectric loss tangent from data taken with a noncontact resonance microwave cavity, assembled with an air‐filled, standard R100 rectangular waveguide configuration. By using amorphous boron nitride (a‐BN) as an encapsulation layer, stability of EG's electrical properties under ambient laboratory conditions is greatly improved. Moreover, samples are exposed to a variety of environmental and chemical conditions. Both thicknesses of a‐BN encapsulation are sufficient to preserve surface conductivity and dielectric loss tangent to within 10% of its previously measured value, a result which has essential importance in the mass production of millimeter‐scale graphene devices demonstrating electrical stability.  相似文献   
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Maximum A Posteriori (MAP) decoding is a crucial enabler of turbo coding and other powerful feedback-based algorithms. To allow pervasive use of these techniques in resources constrained systems, it is important to limit their implementation complexity, without sacrificing the superior performance they are known for. We show that introducing traceback information into the MAP algorithm, thereby leveraging components that are also part of Soft-Output Viterbi Algorithms (SOVA), offers two unique possibilities to simplify the computational requirements. Our proposed enhancements are effective at each individual decoding iteration and therefore provide gains on top of existing techniques such as early termination and memory optimizations. Based on these enhancements, we will present three new architectural variants for the decoder. Each one of these may be preferable depending on the decoder memory hardware requirements and number of trellis states. Computational complexity is reduced significantly, without incurring significant performance penalty.
Curt SchurgersEmail:

Curt Schurgers   is currently an assistant professor at the University of California, San Diego. He received his M.S. degree from the Katholieke Universiteit Leuven in Belgium in 1997, and his Ph.D. from UCLA in 2002. He was also a researcher at the Interuniversity Microelectronics Center in Belgium (1997-1999), and a postdoctoral researcher at MIT (2003). His research interests include energy efficient communication systems, sensor networks and underwater networks. Anantha P. Chandrakasan   received the B.S, M.S. and Ph.D. degrees in Electrical Engineering and Computer Sciences from the University of California, Berkeley, in 1989, 1990, and 1994 respectively. Since September 1994, he has been with the Massachusetts Institute of Technology, Cambridge, where he is currently the Joseph F. and Nancy P. Keithley Professor of Electrical Engineering. He was a co-recipient of several awards including the 1993 IEEE Communications Society’s Best Tutorial Paper Award, the IEEE Electron Devices Society’s 1997 Paul Rappaport Award for the Best Paper in an EDS publication during 1997, the 1999 DAC Design Contest Award, the 2004 DAC/ISSCC Student Design Contest Award, the 2007 ISSCC Beatrice Winner Award for Editorial Excellence and the 2007 ISSCC Jack Kilby Award for Outstanding Student Paper. His research interests include low-power digital integrated circuit design, wireless microsensors, ultra-wideband radios, and emerging technologies. He is a co-author of Low Power Digital CMOS Design (Kluwer Academic Publishers, 1995), Digital Integrated Circuits (Pearson Prentice-Hall, 2003, 2nd edition), and Subthreshold Design for Ultra-Low Power Systems (Springer 2006). He is also a co-editor of Low Power CMOS Design (IEEE Press, 1998), Design of High-Performance Microprocessor Circuits (IEEE Press, 2000), and Leakage in Nanometer CMOS Technologies (Springer, 2005). He has served as a technical program co-chair for the 1997 International Symposium on Low Power Electronics and Design (ISLPED), VLSI Design '98, and the 1998 IEEE Workshop on Signal Processing Systems. He was the Signal Processing Sub-committee Chair for ISSCC 1999–2001, the Program Vice-Chair for ISSCC 2002, the Program Chair for ISSCC 2003, and the Technology Directions Sub-committee Chair for ISSCC 2004–2008. He was an Associate Editor for the IEEE Journal of Solid-State Circuits from 1998 to 2001. He served on SSCS AdCom from 2000 to 2007 and he was the meetings committee chair from 2004 to 2007. He is the Technology Directions Chair for ISSCC 2009. He is the Director of the MIT Microsystems Technology Laboratories.   相似文献   
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