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51.
This paper presents tangible augmented reality gaming environment that can be used to enhance entertainment using a multimodal tracking interface. Players can interact using different combinations between a pinch glove, a Wiimote, a six-degrees-of-freedom tracker, through tangible ways as well as through I/O controls. Two tabletop augmented reality games have been designed and implemented including a racing game and a pile game. The goal of the augmented reality racing game is to start the car and move around the track without colliding with either the wall or the objects that exist in the gaming arena. Initial evaluation results showed that multimodal-based interaction games can be beneficial in gaming. Based on these results, an augmented reality pile game was implemented with goal of completing a circuit of pipes (from a starting point to an end point on a grid). Initial evaluation showed that tangible interaction is preferred to keyboard interaction and that tangible games are much more enjoyable.  相似文献   
52.
Lithium has been used clinically in the treatment of manic depression. However, its pharmacologic mode of action remains unclear. Characteristics of Li+ interactions in red blood cells (RBCs) have been identified. We investigated Li+ interactions on human neuroblastoma SH-SY5Y cells by developing a novel 7Li NMR method that provided a clear estimation of the intra- and extracellular amounts of Li+ in the presence of the shift reagent thulium-1,4,7,10-tetrazacyclododecane-N,N',N',N'-tetramethylene phosphonate (HTmDOTP4-). The first-order rate constants of Li+ influx and efflux for perfused, agarose-embedded SH-SY5Y cells in the presence of 3 mM HTmDOTP4- were 0.055 +/- 0.006 (n = 4) and -0.025 +/- 0.006 min(-1) (n = 3), respectively. Significant increases in the rate constants of Li+ influx and efflux in the presence of 0.05 mM veratridine indicated the presence of Na+ channel-mediated Li+ transport in SH-SY5Y cells. 7Li NMR relaxation measurements showed that Li+ is immobilized more in human neuroblastoma SH-SY5Y cells than in human RBCs.  相似文献   
53.
Degradation experiments are usually used to assess the lifetime distribution of highly reliable products, which are not likely to fail under the traditional life tests or accelerated life tests. In such cases, if there exist product characteristics whose degradation over time can be related to reliability, then collecting ‘degradation data’ can provide information about product reliability. In general, the degradation data are modeled by a nonlinear regression model with random coefficients. If we can obtain the estimates of parameters under the model, then the failure‐time distribution can be estimated. In order to estimate those parameters, three basic methods are available, namely, the analytical, numerical and the approximate. They are chosen according to the complexity of the degradation path model used in the analysis. In this paper, the numerical and the approximate methods are compared in a simulation study, assuming a simple linear degradation path model. A comparison with traditional failure‐time analysis is also performed. The mean‐squared error of the estimated 100pth percentile of the lifetime distribution is evaluated for each one of the approaches. The approaches are applied to a real degradation data set. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
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In the homodimeric hemoglobin from Scapharca, HbI, functional communication between the two heme groups is based on their direct structural linkage across the subunit interface through the heme propionates. The heme-protein interactions have been altered in deutero- and meso-HbI by substituting the vinyl groups at positions 2 and 4 of protoheme with hydrogen and ethyl groups, respectively. In meso-HbI the introduction of the ethyl groups in the heme pocket induces significant alterations in the conformation of the heme peripheral substituents, including the propionates, and in the structure of bound CO, as revealed by the resonance Raman spectra. The functional counterpart of these structural changes is the loss of cooperativity in carbon monoxide binding and in the rate of oxygen dissociation. Oxygen pulse and flash photolysis experiments indicate that meso-HbI is locked in the liganded conformation. It is postulated that the ethyl groups, which occupy a larger volume than vinyl ones, impair the ligand-linked movement of the heme relative to its pocket and in turn the expression of cooperativity. In deutero-HbI structural alterations have not been monitored. Functionally, cooperativity in the CO binding kinetics is increased as if hydrogen atoms at positions 2 and 4 permitted more marked movements of the heme than in the native protein.  相似文献   
56.
Diffusion tensor imaging (DTI) is a powerful technique for imaging axonal anatomy in vivo and its automatic segmentation is important for quantitative analysis and visualization. Application of the watershed transform is a recent approach for robustly segmenting diffusion tensor images. Since an important step of the watershed-based segmentation is the gradient computation, this paper investigates scalar maps from DTI and their ability to enhance borders and, therefore, their usefulness in gradient calculation. A comparison between existing scalar maps is conducted in the context of segmentation. New diffusion scalar maps, inspired by mathematical morphology concepts are proposed and included in the comparison. The watershed transform is then applied to segment the corpus callosum, based on the computed scalar maps.  相似文献   
57.
In this study, the charge efficiency, nucleation growth, and morphology of electrodeposited copper from spent Li-batteries were studied. The charge efficiency for these deposits shows a maximum value of 99.41%, under a charge density of 5.0 C cm?2. Studies with the SEM technique at pH 2.0 show well-formed nuclei. At pH 4.5, the deposits take the form of dendrites. XRD analysis shows that, in both cases, a Cu2O structure is present, but with a large amount at pH 4.5, evidenced by peaks of [002] and [110] directions.  相似文献   
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59.
The practice of predictive maintenance depends significantly on the diagnosis of in-service performance and on the decision criteria for the selection of maintenance tasks. The definition of these criteria is limited because several actors are involved, each with their own perspectives of performance and maintenance needs. This paper discusses a set of 17 criteria to help the maintenance choice for building fa?ades, from three viewpoints: physical performance, risk, and costs. A group of experts was surveyed and 30 answers were received. Therefore, each criterion will be discussed according to the answers collected. The relative importance (using quantitative weights) and subclasses for each criterion are proposed.  相似文献   
60.
Performance of frequency relays for distributed generation protection   总被引:1,自引:0,他引:1  
This paper investigates the efficiency of under/over frequency relays for protection of distributed synchronous generators considering islanding detection and frequency-tripping requirements. Comparison between frequency and vector surge relays, which are islanding detection-dedicated devices, shows that the former can be as effective as the latter. This feature supports the idea that frequency relays can replace vector surge relays for islanding detection purpose. In this case, frequency relays must also meet the generator manufacturer recommendations and the utility frequency-tripping requirements. In order to investigate the relay capability to meet both necessities, it is proposed the concept of application region, which defines a region in the detection time versus active power imbalance space where frequency-based relays can be adjusted to satisfy the anti-islanding and frequency-tripping requirements simultaneously. The paper also presents a set of formulas to determine directly the application region.  相似文献   
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