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991.
Bo Ren Longbiao Wang Liang Lu Yuma Ueda Atsuhiko Kai 《Multimedia Tools and Applications》2016,75(9):5093-5108
The performance of speech recognition in distant-talking environments is severely degraded by the reverberation that can occur in enclosed spaces (e.g., meeting rooms). To mitigate this degradation, dereverberation techniques such as network structure-based denoising autoencoders and multi-step linear prediction are used to improve the recognition accuracy of reverberant speech. Regardless of the reverberant conditions, a novel discriminative bottleneck feature extraction approach has been demonstrated to be effective for speech recognition under a range of conditions. As bottleneck feature extraction is not primarily designed for dereverberation, we are interested in whether it can compensate for other carefully designed dereverberation approaches. In this paper, we propose three schemes covering both front-end processing (cascaded combination and parallel combination) and back-end processing (system combination). Each of these schemes integrates bottleneck feature extraction with dereverberation. The effectiveness of these schemes is evaluated via a series of experiments using the REVERB challenge dataset. 相似文献
992.
Large-scale cloud animation is crucial to TV weather presentation, weather observer training and video products. In this paper, a physically based system is presented for the derivation of time-varying 3D clouds from geostationary satellite images. Cloud properties are derived from a set of meteorological models while the clouds are rendered by graphics models, the proposed method thus presents a new modeling methodology, which integrates the reality of the data with the realistic visual feeling. In particular, image pixels are first classified into cloud-free, water cloud, ice cloud, thin cirrus cloud in terms of their spectral signature. Then, cloud top surface, cloud bottom surface and cloud extinction are generated by applying different combinations of images. Finally, clouds are rendered under various light directions or view directions. The results have indicated that the proposed method can yield a realistic and approximately valid clouds with similar appearance to those in the input satellite images. 相似文献
993.
Li Fuliang Gong Junfeng Liang Yunyi Zhou Jiali 《Multimedia Tools and Applications》2016,75(24):17573-17592
Multimedia Tools and Applications - Congestion prediction can support traffic departments to take effective traffic management measures, and it aids users to adopt smarter trip strategies,... 相似文献
994.
Liang Feng Ah-Hwee Tan Meng-Hiot Lim Si Wei Jiang 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2016,20(12):4685-4693
Band selection plays an important role in identifying the most useful and valuable information contained in the hyperspectral images for further data analysis such as classification, clustering, etc. Memetic algorithm (MA), among other metaheuristic search methods, has been shown to achieve competitive performances in solving the NP-hard band selection problem. In this paper, we propose a formal probabilistic memetic algorithm for band selection, which is able to adaptively control the degree of global exploration against local exploitation as the search progresses. To verify the effectiveness of the proposed probabilistic mechanism, empirical studies conducted on five well-known hyperspectral images against two recently proposed state-of-the-art MAs for band selection are presented. 相似文献
995.
Quantum circuits of the generalized affine transform are devised based on the novel enhanced quantum representation of digital images. A novel quantum image encryption algorithm combining the generalized affine transform with logistic map is suggested. The gray-level information of the quantum image is encrypted by the XOR operation with a key generator controlled by the logistic map, while the position information of the quantum image is encoded by the generalized affine transform. The encryption keys include the independent control parameters used in the generalized affine transform and the logistic map. Thus, the key space is large enough to frustrate the possible brute-force attack. Numerical simulations and analyses indicate that the proposed algorithm is realizable, robust and has a better performance than its classical counterpart in terms of computational complexity. 相似文献
996.
Liang Liu Chaoying Chen Xinhua Zhao Yangmin Li 《International Journal of Control, Automation and Systems》2016,14(4):1022-1036
In order to achieve better tracking accuracy effectively, a new smooth and near time-optimal trajectory planning approach is proposed for a parallel manipulator subject to kinematic and dynamic constraints. The complete dynamic model is constructed with consideration of all joint frictions. The presented planning problem can be solved efficiently by formulating a new limitation curve for dynamic constraints and a reduced form for jerk constraints. The motion trajectory is planned with quartic and quintic polynomial splines in Cartesian space and septuple polynomial splines in joint space. Experimental results show that smaller tracking error can be obtained. The developed method can be applied to any robots with analytical inverse kinematic and dynamic solutions. 相似文献
997.
In this work, we have put forth two different protocols to address a concrete secure multi-party computational (MPC) problem related to a triangle, of which the coordinates of the three vertices are confidentially kept by the three participants, respectively. The three parties wish to collaboratively compute the area of this triangle while preserving their own coordinate privacy. As one of the merits, our protocols employ weaker assumptions of the existence of pseudorandom generators. In particular, unlike massive secure MPC protocols that rely a lot on oblivious transfer, ours utilize a new computing idea called “pseudorandom-then-rounding” method to avoid this burdensome obstacle. The two protocols are based on different theorems, while they both make use of the same underlying idea. At last, we provide a detailed proof for the first protocol by a series of security reductions of our newly defined games, which seems somewhat stronger than the previous simulation-based proofs and a proof sketch for the second one. Analysis and discussion about the reasons are provided as well to round off our work. 相似文献
998.
Zilu Liang Bernd Ploderer Wanyu Liu Yukiko Nagata James Bailey Lars Kulik Yuxuan Li 《Personal and Ubiquitous Computing》2016,20(6):985-1000
Getting enough quality sleep is a key part of a healthy lifestyle. Many people are tracking their sleep through mobile and wearable technology, together with contextual information that may influence sleep quality, like exercise, diet, and stress. However, there is limited support to help people make sense of this wealth of data, i.e., to explore the relationship between sleep data and contextual data. We strive to bridge this gap between sleep-tracking and sense-making through the design of SleepExplorer, a web-based tool that helps individuals understand sleep quality through multi-dimensional sleep structure and explore correlations between sleep data and contextual information. Based on a two-week field study with 12 participants, this paper offers a rich understanding on how technology can support sense-making on personal sleep data: SleepExplorer organizes a flux of sleep data into sleep structure, guides sleep-tracking activities, highlights connections between sleep and contributing factors, and supports individuals in taking actions. We discuss challenges and opportunities to inform the work of researchers and designers creating data-driven health and well-being applications. 相似文献
999.
某药业股份有限公司克林霉素生产废水采用高级氧化-IC-曝气工艺处理,重点介绍了工程的调试启动。工程运行结果表明,出水水质稳定,COD为112mg/L,BOD5为23mg/L,SS为48mg/L,NH3-N为37.1mg/L,TN为49.6mg/L,硫化物为0.72mg/L,急性毒性(以HgCl2毒性当量计)为0.05mg/L,pH为8.22,处理后出水毒性和有机物浓度都大大降低,各项水质指标符合《化学合成类制药工业水污染物排放标准》(GB 21904-2008)的要求。 相似文献
1000.
图谱法脑部MRI图像自动分割技术发展及应用 总被引:1,自引:0,他引:1
脑部MRI图像自动分割是计算机技术运用于医学上的一个典
型工作,脑部图像分割技术对于人类研究脑部疾病具有重要意义。虽然有一些非常广泛应用
的图像分割方法,如阈值法、区域增长法、聚类法等,但在脑部MRI图像分割中,这些方法
都
没有图谱法具有更为实际的医学研究与临床价值。本文回顾了脑部图像配准、分割的发展历
程,介绍了图谱分割算法的发展及基本原理,以及当前比较前沿的多图谱分割系统的组成和
应用。最后本文对图谱法脑部自动分割在实际临床医学中的应用前景作了总结和展望。 相似文献