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61.
62.
Zhiguo Ren Wenjing Gai Fan Zhong Julien Pettré Qunsheng Peng 《The Visual computer》2013,29(9):927-936
In this paper, we propose a novel approach to integrate virtual pedestrians into a scene of real pedestrian groups with behavior consistency, and this is achieved by dynamic path planning of virtual pedestrians. Rather than accounting for the local collision avoidance only, our approach is capable of finding an optimized path for each virtual pedestrian on his way based on the current global distribution of the real groups in the scene. The big challenge is due to the information of both position and velocity of real pedestrians in the video being unavailable; also the distribution of the groups in the scene may vary dynamically. We therefore need to detect and track real pedestrians on each frame of the video to acquire their distribution and motion information. We save this information by an efficient data structure, called environment grid. During the way of a virtual pedestrian, the respective agent frequently emits the detection rays through the environment cells to find the situation of the real pedestrians ahead of him and adjust the original path if necessary. Virtual pedestrians are merged into the video finally with the occlusion between virtual characters and the real pedestrians correctly presented. Experiment results on several scenarios demonstrate the effectiveness of the proposed approach. 相似文献
63.
Jiading Gai Nady Obeid Joseph L. Holtrop Xiao-Long Wu Fan Lam Maojing Fu Justin P. Haldar Wen-mei W. Hwu Zhi-Pei Liang Bradley P. Sutton 《Journal of Parallel and Distributed Computing》2013
Several recent methods have been proposed to obtain significant speed-ups in MRI image reconstruction by leveraging the computational power of GPUs. Previously, we implemented a GPU-based image reconstruction technique called the Illinois Massively Parallel Acquisition Toolkit for Image reconstruction with ENhanced Throughput in MRI (IMPATIENT MRI) for reconstructing data collected along arbitrary 3D trajectories. In this paper, we improve IMPATIENT by removing computational bottlenecks by using a gridding approach to accelerate the computation of various data structures needed by the previous routine. Further, we enhance the routine with capabilities for off-resonance correction and multi-sensor parallel imaging reconstruction. Through implementation of optimized gridding into our iterative reconstruction scheme, speed-ups of more than a factor of 200 are provided in the improved GPU implementation compared to the previous accelerated GPU code. 相似文献
64.
Exhaustive indole oxidation in aqueous solution was studied using contact glow discharge plasma. The results indicated that
the rate of indole degradation increases with the decrease in the solution conductivity. The degradation rate can be enhanced
under the following situations. First, the increase in temperature. Second, introduce active carbon and hydrogen peroxide
to the solution. Third, the degradation process is performed in alkaline or acidic media rather than the neutral media. Fourth,
add Fe2+ to solution to undergo Fenton’s reaction. However, n-butanol was found decelerate the degradation of indole. Some major intermediates
produced during the degradation were detected by using both HPLC and GC-MS. 相似文献
65.
This work concerns the underestimation of the errors in the recommended neutron cross sections obtained by using strict statistical
methods to analyze measurements. It is shown that one reason for this is inadequate representation of the initial experimental
data, specifically, correlations of the experimental data are neglected. The effect of correlations of the experimental data
on the error in the evaluated neutron cross sections is studied using realistic models and practical examples. Special attention
is focussed on correlations of measurements performed by different authors. Analysis of correlations of this kind substantially
increases the errors in the evaluated cross sections. Analysis of the model examples shows that the correction can be large
(∼70%) even for cases with relatively weak correlation of the measurements performed by different authors. For the evaluated
cross sections of the reactions103Rh(n, n′)103mRh and237Np(n, f) the corrections reach 41% and 25% for certain energy ranges. 5 figures, 1 table, 22 references.
Federal Science Center of the Russian Federation—A. I. Leipunskii Physics and Power-Engineering Institute. Translated from
Atomnaya énergiya, Vol. 86, No. 1, pp. 40–46, January, 1990. 相似文献
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杉浦康平先生作为日本著名的书籍装帧设计家,其作品及设计理念在中国、亚洲乃至世界都有着很强的感染力和影响力,十余年在与中国的交流过程中无论于设计的实践与设计理念的指导均给中国书籍装帧设计的发展带来了许多可贵的启示和作用。本文试图通过对杉浦康平先生的设计理念、设计作品中设计语汇的分析,使中国书籍装帧设计者能够清晰地看待和解析日本设计与其本土文化的融合,站在新的角度重新审视传统、放眼未来,为构建更为广阔的设计空间而寻觅出一条可行之路。 相似文献
69.
The underestimation of the errors in the recommended neutron cross sections calculated on the basis of an analysis of measurement results using strict statistical methods is discussed. The basic reasons for the underestimation of the errors in the cross sections are described. A statistical model is proposed — a constant bias model — for taking into account effectively the component of the measurement error that is unknown to the experimentor. The results of a statistical analysis of the measurements of the ratio of the fission cross sections of 238U and 235U on the basis of the constant bias model are presented. It is noted that the experimental errors are much higher (on the average by a factor of 2) than the declared errors. The consequences of using the generally accepted method for correcting the errors in the evaluated cross sections are examined for an exactly solvable model example. It is shown that such a procedure does reconstruct the real errors in the evaluated cross sections.__________Translated from Atomnaya Énergiya, Vol. 98, No. 1, pp. 3–12, January, 2005. 相似文献
70.
Xiao Dian Zhao Xiaoyan Li Kunpeng Zhao Xiucheng Liu Hongwei Li Xun Luo Gai 《Bulletin of Engineering Geology and the Environment》2021,80(5):3659-3673
Bulletin of Engineering Geology and the Environment - Acid rain has important influences on the physical and mechanical properties of rock as a result of mineral conversion and dissolution of... 相似文献