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81.
城市智能交通控制系统研究与设计 总被引:2,自引:0,他引:2
智能交通系统是当前我国交通运输领域的前沿研究课题。研究的核心是针对日益严重的交通需求和交通资源的压力,采用信息技术、通信技术、计算机技术,从城市交通系统的分类出发,分析基于城市交通控制系统的可行性,并提出城市智能交通控制系统研究与设计,指出智能交通系统的系统控制理论、交通信息的智能处理、应用及其性能改善。 相似文献
82.
Bringing a single still image into reality is a challenging topic in computer animation because the driven and structural information in single still image is inadequate. In this paper, we present an image animating method for enhancing single still image in social media with virtual realistic and animated motions without prior information. We imitate the interaction between the active objects in an image and their neighboring passive objects. The existing actions in the image and the virtual specified force are employed to animate the active objects. Observing that the change between two subsequent motions of the active objects derives a motion tendency, we can calculate a virtual driving force based on the motion tendency. By virtue of the virtual driving force, the stochastic motion texture is used to animate the passive objects. Finally, the convolutional neural network is employed to optimize the virtual motion animations. In this way, the proposed method produces visually natural results while guaranteeing motion harmony between active objects and passive objects. To demonstrate the applicability and rationality of virtual animation driving force, our method generates several animations from still images in Social Media. 相似文献
83.
Rate-distortion optimization (RDO) is conventionally based on the analysis of rate-distortion (R-D) curve to minimize the coding distortion under the coding bits constraint. However, it is necessary to consider the computational complexity in the RDO process. In this paper, we obtain the Confidence LEvel - Computational complexity (CLEC) curves which indicate the characteristics of coding tree units (CTUs). Based on the CLEC curves, a rate-distortion-complexity optimization (RDCO) algorithm is proposed to optimize R-D under given computational complexity and achieve the optimal coding performance for x265. Experimental results demonstrate that the proposed algorithm can achieve a wide range of encoding speed under a given quantization parameter (QP) whereas the original x265 can only achieve a few fixed encoding speeds, and the proposed algorithm can reduce the BD-rate and increase the BD-PSNR by 6.59% and 0.13 dB on average under the same requirements of encoding speeds as the original x265. 相似文献
84.
针对人脸识别问题,提出采用深度特征筛选及融合的方法.采用卷积神经网络(CNN)学习人脸图像的多层次深度特征.对于所有的深度特征矢量,使用斯皮尔曼等级相关系数筛选其中有效部分.基于支持向量机(SVM)对筛选得到的任一深度特征矢量进行分类决策,并基于线性加权融合对它们的结果进行融合,最终确定待识别样本的人脸类别.基于ORL... 相似文献
85.
文章主要从VR技术原理出发,分析了VR技术中使用的软硬件系统,讨论了健美操仿真的关键技术,最后对其在健美操运动中应用可行性做了分析研究。 相似文献
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The impact of defect concentration and current density on the effective singlet exciton diffusion length in 4’-bis(carbazol-9-yl)biphenyl (CBP) is quantified by analyzing the electroluminescent characteristics of several sets of OLEDs. The defect concentration and effective diffusion length are determined through fitting of the defect and CBP emission bands in the electroluminescence spectra under constant current operation using an analytical model derived based on the competition between exciton diffusion and energy transfer to defects. Defect concentrations of 3 ± 1 × 1018 cm−3, 2 ± 1 × 1018 cm−3 and 0.3 ± 0.7 × 1018 cm−3 are calculated in three sets of OLEDs, in which the effective diffusion length decreases as the defect concentration increases. Modelling the dependence of the effective diffusion length on defect concentration a “defect free” diffusion length of 4.5 ± 0.3 nm is obtained for CBP singlet excitons in these devices operated under low current density. We also show that the driving voltage scales linearly with the defect concentration. 相似文献
89.
随着我国经济的发展,人们生活水平的提高,居民和各行各业对供电的需求和依赖程度越来越高,传统的供电方式已不能满足用户对供电的要求,这就要采取配电系统自动化运行方式,来保证供电的质量,满足用户的不同要求。 相似文献
90.
To develop a low cost and highly effective metallurgical route for solar-grade Si production, we investigated the zone melting directional solidification method. In this method, bulk crystalline Si is successfully produced from Si-Sn solvent; this bulk crystalline Si demonstrates a steady growth interface and excellent compositional uniformity. Moreover, the growth rate of bulk crystalline Si along the axial direction increases because the remaining MG-Si serves as Si source to keep the Si-Sn solution saturated with Si atoms, and it is approximately three times larger than that of Si by using the Si-based alloy directional solidification method without Si source. In this work, the evolution of impurity phases segregated in different regions along the axial direction is extensively discussed. The distribution and amount of impurities, including Ca, Al, B, and P, are effectively controlled by this refining method, further improving the quality of bulk crystalline Si. 相似文献