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41.
A new 4T2C pixel circuit formed on a silicon substrate is proposed to realize a high‐resolution 7.8‐μm pixel pitch AMOLED microdisplay. In order to achieve high luminance uniformity, the pixel circuit compensates its Vth variation of the MOSFET for the driving transistor internally by using self‐discharging method. Also presented are 0.5‐in Quad‐VGA and 1.25‐in wide Quad‐XGA microdisplays with the proposed pixel circuit.  相似文献   
42.
How the human central nervous system adjusts sensorimotor coordination to haptic stimuli is a major topic in several fields including robotics. There are studies focusing on contact positioning tasks such as catching a ball or a volley in tennis, where position control of a human hand is required only at the moment of contact for successful completion of the tasks. A previous study dealt with a task of catching a ball in a virtual environment, and reported an interesting observation of the learning process in the relationship between operational performance and energy consumption of an operator; however, the operational condition given to the operators in the previous study seemed to be relatively simple. The interest in this paper is similar to that of the previous study; however, this paper considers application of a slightly more complex operational condition to a task of catching a ball. For corresponding to increase of difficulty in operation in the task, two movements of a paddle for catching a ball are given to operators, and difference between the movements is observed. Although the final goal of the study in this paper is similar to that in the previous study, this paper considers how learning effect can be observed in operational performance by comparing the performance of novice operators with that of experienced operators. The comparison shows differences in the performances between the operators from three analytic aspects. This paper also considers how many operations are required for novice operators to exhibit the learning effect in operational performance.  相似文献   
43.
In this research, we propose and evaluate a decision support system using an interactive large-scale high-resolution display. This decision support system supports the summarization and decision-making of a large amount of disaster information during the occurrence of a large-scale natural disaster. Municipal employees at the disaster control headquarters can display disaster information on the large-scale display with a touch or flick on a laptop or tablet. To evaluate the operability, readability, functionality, and necessity of the decision support system, we surveyed 23 municipal employees in the disaster prevention division using a questionnaire. The system received a great evaluation in all the evaluation items.  相似文献   
44.
We consider the minimum maximal matching problem, which is NP-hard (Yannakakis and Gavril (1980) [18]). Given an unweighted simple graph G=(V,E), the problem seeks to find a maximal matching of minimum cardinality. It was unknown whether there exists a non-trivial approximation algorithm whose approximation ratio is less than 2 for any simple graph. Recently, Z. Gotthilf et al. (2008) [5] presented a -approximation algorithm, where c is an arbitrary constant.In this paper, we present a -approximation algorithm based on an LP relaxation, where χ(G) is the edge-coloring number of G. Our algorithm is the first non-trivial approximation algorithm whose approximation ratio is independent of |V|. Moreover, it is known that the minimum maximal matching problem is equivalent to the edge dominating set problem. Therefore, the edge dominating set problem is also -approximable. From edge-coloring theory, the approximation ratio of our algorithm is , where Δ(G) represents the maximum degree of G. In our algorithm, an LP formulation for the edge dominating set problem is used. Fujito and Nagamochi (2002) [4] showed the integrality gap of the LP formulation for bipartite graphs is at least . Moreover, χ(G) is Δ(G) for bipartite graphs. Thus, as far as an approximation algorithm for the minimum maximal matching problem uses the LP formulation, we believe our result is the best possible.  相似文献   
45.
There are two major ways of calculating ray and parametric surface intersections in rendering. The first is through the use of tessellated triangles, and the second is to use parametric surfaces together with numerical methods such as Newton's method. Both methods are computationally expensive and complicated to implement. In this paper, we focus on Phong Tessellation and introduce a simple direct ray tracing method for Phong Tessellation. Our method enables rendering smooth surfaces in a computationally inexpensive yet robust way.  相似文献   
46.
Summary Hydro- and vinyl-bifunctionalized di- or tetrasiloxane were synthesized by degradative cleavage of functional cyclic siloxanes with methyllithium followed by quenching with a functional chlorosilane, or by ring-opening of hexamethylcyclotrisiloxane (D3) by functional alkyllithium followed by quenching with a functional chlorosilane. These bifunctionalized siloxanes were used as monomers in polyaddition with transition metal catalysts.  相似文献   
47.
A novel chromatographic separation technique using a tertiary pyridine type resin has been applied to the partitioning of the trivalent actinides (An) and lanthanides (Ln) and several successful results have been shown. In an alcoholic hydrochloric acid system, the trivalent An were clearly separated from the Ln, while no such group separation was achieved in an alcoholic nitric acid system. On the other hand, the nitric acid system was more effective for the intragroup (i.e. individual) separation of the trivalent An and the Ln than the hydrochloric acid system. On the basis of these results, a novel concept for the partitioning of the trivalent An and Ln using the present separation technique and its flowchart have been proposed with its advantages and disadvantages.  相似文献   
48.
The low-temperature shrinking of the vortex core (Kramer-Pesch effect) is studied for an isolated single vortex for chiral p-wave and s-wave superconducting phases. The effect of nonmagnetic impurities on the vortex core radius is numerically investigated in the Born limit by means of a quasiclassical approach. It is shown that in the chiral p-wave phase the Kramer-Pesch effect displays a certain robustness against impurities owing to a specific quantum effect, while the s-wave phase reacts more sensitively to impurity scattering. This suggests chiral p-wave superconductors as promising candidates for the experimental observation of the Kramer-Pesch effect.  相似文献   
49.
The effect of gravity on dissolution of GaSb in InSb melt and growth of InGaSb was experimentally investigated. Experiments were carried out in a GaSb(seed)/InSb/GaSb(feed) sandwich system under an imposed temperature gradient. In the experiments, the GaSb feed crystal dissolved into the InSb melt to supply the required GaSb component for the growth of In0.1Ga0.9Sb crystal. Two parameters were considered: (1) the inclination angle (θ) of the sample for gravity as 0° and 53°, and (2) the sample diameter (D) as 9 mm and 5mm. When θ was 0°, the interface was almost flat, indicating that convection was axisymmetric and stable. Whereas the interface was distorted towards gravitational direction when θ was 53°, indicating that solutal convection was dominant. The decrease of growth temperature and sample diameter reduced the distortion of interface and the dissolution amount of GaSb feed. The homogeneous crystals were grown at the initial growth stage by supplying the GaSb component during growth.  相似文献   
50.
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