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21.
Solution‐Processed Organic–Inorganic Perovskite Field‐Effect Transistors with High Hole Mobilities
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22.
This paper describes a level-of-detail rendering technique for large-scale irregular volume datasets. It is well known that
the memory bandwidth consumed by visibility sorting becomes the limiting factor when carrying out volume rendering of such
datasets. To develop a sorting-free volume rendering technique, we previously proposed a particle-based technique that generates
opaque and emissive particles using a density function constant within an irregular volume cell and projects the particles
onto an image plane with sub-pixels. When the density function changes significantly in an irregular volume cell, the cell
boundary may become prominent, which can cause blocky noise. When the number of the sub-pixels increases, the required frame
buffer tends to be large. To solve this problem, this work proposes a new particle-based volume rendering which generates
particles using metropolis sampling and renders the particles using the ensemble average. To confirm the effectiveness of
this method, we applied our proposed technique to several irregular volume datasets, with the result that the ensemble average
outperforms the sub-pixel average in computational complexity and memory usage. In addition, the ensemble average technique
allowed us to implement a level of detail in the interactive rendering of a 71-million-cell hexahedral volume dataset and
a 26-million-cell quadratic tetrahedral volume dataset. 相似文献
23.
Combinatorial problems appear in many areas in science, engineering, biomedicine, business, and operations research. This article presents a new intelligent computing approach for solving combinatorial problems, involving permutations and combinations, by incorporating logic programming. An overview of applied combinatorial problems in various domains is given. Such computationally hard and popular combinatorial problems as the traveling salesman problem are discussed to illustrate the usefulness of the logic programming approach. Detailed discussions of implementation of combinatorial problems with time complexity analyses are presented in Prolog, the standard language of logic programming. These programs can be easily integrated into other systems to implement logic programming in combinatorics. 相似文献
24.
25.
Ding Zhongming Takuma Kawamura Naohisa Sakamoto Koji Koyamada 《Simulation Modelling Practice and Theory》2010,18(8):1172-1183
In this paper, we describe an improved particle-based volume rendering (PBVR) technique for previewing a large irregular volume dataset using the CUDA architecture. This technique allows for opaque and emissive particles to render translucent volumes without visibility sorting. Our GPU acceleration of PBVR provides the multi-volume rendering feature while remaining compatible with both regular and irregular volumes. We also reduce the memory cost required for storing all sub-pixel values by proposing a pixel repetition technique for a large sub-pixel level. By adjusting the repetition level, we achieved a very smooth level of detail (LOD) control for trading quality for speed. Our work demonstrates a full-detail rendering rate from 5 to 10 fps for irregular volume data with mega-scale cell numbers on an NVIDIA GeForce 8800GTS. 相似文献
26.
Tree is a data structure used to express various objects such as semistructured data and genes. When objects are represented as trees, computing tree similarity is essential for pattern recognition and retrieval. This paper considers the noisy subsequence tree recognition problem whose purpose is to recognize the original tree, given its noisy subsequence tree. Previous research on this problem relied on constrained tree edit distance to measure the dissimilarity. However, the number of relabelings must be predetermined to compute it. This paper proposes a new dissimilarity measure for this problem. Our dissimilarity measure is obtained by counting the node edit operations included in the unit‐cost tree edit distance that contribute to the matching of node labels. The number of relabelings need not be specified to compute our dissimilarity measure. Moreover, our measure achieves more accurate recognition performance and faster execution speed than the constrained tree edit distance. Our measure is also useful to solve the tree inclusion problem which is the problem of deciding whether a tree includes another tree and shows the extent of approximate tree inclusion when a tree incompletely includes another tree. © 2011 Wiley Periodicals, Inc. 相似文献
27.
28.
Yoshimasa A. Ono Jun'ichiro Hara Katsuhiko Nagai Kiyoshi Kawamura 《Journal of Low Temperature Physics》1977,27(3-4):513-536
The shear viscosity (T) in the Balian-Werthamer (BW) state of superfluid
3
He is calculated variationally throughout the region 0t 1(t=T/T
c) from the transport equation for Bogoliubov quasiparticles. Coherence factors are treated exactly in the calculation of the collision integral. The numerical result for
=s= s(T)/n(Tc) agree very well with experiment in the range 0.8t1.0. Analytic expressions
= 0.577 (1–1.0008t) and
=1–(23/64) [=(T)/k
B
T] are obtained in the low-temperature region and in the vicinity ofT
c, respectively. From the numerical analysis it is shown that the latter equation is valid only in the temperature range 0.9997t1.0.Supported by the Research Institute for Fundamental Physics, Kyoto University. 相似文献
29.
In a half-zone (HZ) liquid bridge, flow exhibits a transition from a two-dimensional steady to a three-dimensional oscillatory flow if the Marangoni number Ma exceeds a critical value Mac, or ΔT>ΔTc. In case of high Prandtle number fluids, the Mac obtained in the numerical simulations deviated significantly from the ones by the experiments. One of the causes of the difference is due to the heat loss over the free surface. Most of past researches neglected effects of the heat loss through an interface of the liquid bridge. Recently several experimental and analytical works reported that the critical condition is significantly affected by the heat loss. The present study aims to include the effects of the heat loss upon the Mac. As the result, the calculated Mac agrees well with the experiment for a high Pr fluid. 相似文献
30.