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941.
Jian‐Peng Cui Feng Zhou Chengqun Song Quan‐Min Zhong Qiong‐Hua Wang 《Journal of the Society for Information Display》2012,20(6):347-350
Abstract— A low‐voltage (~10 Vrms) and high‐transmittance (~90%) polymer‐stabilized blue‐phase liquid‐crystal (BPLC) device with a slanted‐electrodes structure is proposed. Unlike the vertical‐field‐switching (VFS) mode in which oblique incident light and a vertical field are employed, the proposed device utilizes normal incident light and an oblique field. The slanted electrodes generate a strong and uniform oblique electric field, which contributes in obtaining low voltage and high transmittance. Moreover, no couple films or prism sheets are needed, which helps to enhance the optical efficiency and simplify of the device structure. This device has great potential application for emerging BPLC displays and photonic devices. 相似文献
942.
Eye gaze tracking is very useful for quantitatively measuring visual attention in virtual environments. However, most eye
trackers have a limited tracking range, e.g., ±35° in the horizontal direction. This paper proposed a method to combine head
pose tracking and eye gaze tracking together to achieve a large range of tracking in virtual driving simulation environments.
Multiple parallel multilayer perceptrons were used to reconstruct the relationship between head images and head poses. Head
images were represented with the coefficients extracted from Principal Component Analysis. Eye gaze tracking provides precise
results on the front view, while head pose tracking is more suitable for tracking areas of interest than for tracking points
of interest on the side view. 相似文献
943.
Since Boolean network is a powerful tool in describing the genetic regulatory networks, accompanying the development of systems biology, the analysis and control of Boolean networks have attracted much attention from biologists, physicists, and systems scientists. From mathematical point of view, the dynamics of a Boolean (control) network is a discrete-time logical dynamic process. This paper surveys a recently developed technique, called the algebraic approach, based on semi-tensor product. The new technique can deal with not only Boolean networks, which allow each node to take two values, but also k-valued networks, which allow each node to take k different values, and mix-valued networks, which allow nodes to take different numbers of values.The paper provides a comprehensive introduction to the new technique, including (1) mathematical background of this new technique – semi-tensor product of matrices and the matrix expression of logic; (2) dynamic models of Boolean networks, and general (multi- or mix-valued) logical networks; (3) the topological structure of Boolean networks and general networks; (4) the basic control problems of Boolean/general control networks, which include the controllability, observability, realization, stability and stabilization, disturbance decoupling, identification and optimization, etc.; (5) some other related applications. 相似文献
944.
Intra coding in H.264/AVC can significantly improve the compression efficiency but at the cost of high computational complexity. To reduce the complexity, this paper presents an efficient block type decision algorithm for intra prediction. In H.264/AVC high profile, three kinds of block types are supported. This algorithm determines the optimal block type by two steps. The first step is based on the fact that the block type of intra prediction is highly dependent on the smoothness of macroblock. An edge-based feature is introduced to characterize the smoothness, by comparing it with two thresholds impossible block type is firstly filtered out. Then the second step is based on the correlation of block type chosen for different chroma modes. Experimental results show that the proposed fast algorithm can achieve 72.8% time saving on average for encoding the all intra-frame sequence with average 0.75% bit rate increase and 0.05dB PSNR degradation when comparing with the reference software. 相似文献
945.
Fuzzy local maximal marginal embedding for feature extraction 总被引:1,自引:0,他引:1
Cairong Zhao Zhihui Lai Chuancai Liu Xingjian Gu Jianjun Qian 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2012,16(1):77-87
In graph-based linear dimensionality reduction algorithms, it is crucial to construct a neighbor graph that can correctly
reflect the relationship between samples. This paper presents an improved algorithm called fuzzy local maximal marginal embedding
(FLMME) for linear dimensionality reduction. Significantly differing from the existing graph-based algorithms is that two
novel fuzzy gradual graphs are constructed in FLMME, which help to pull the near neighbor samples in same class nearer and
nearer and repel the far neighbor samples of margin between different classes farther and farther when they are projected
to feature subspace. Through the fuzzy gradual graphs, FLMME algorithm has lower sensitivities to the sample variations caused
by varying illumination, expression, viewing conditions and shapes. The proposed FLMME algorithm is evaluated through experiments
by using the WINE database, the Yale and ORL face image databases and the USPS handwriting digital databases. The results
show that the FLMME outperforms PCA, LDA, LPP and local maximal marginal embedding. 相似文献
946.
Jianwei Zhao Dong Sun Park Joonwhoan Lee Feilong Cao 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2012,16(9):1503-1514
Functional data learning is an extension of traditional data learning, that is, learning the data chosen from the Euclidean space ${\mathbb{R}^{n}}$ to a metric space. This paper focuses on the functional data learning with generalized single-hidden layer feedforward neural networks (GSLFNs) acting on some metric spaces. In addition, three learning algorithms, named Hilbert parallel overrelaxation backpropagation (H-PORBP) algorithm, ν-generalized support vector regression (ν-GSVR) and generalized extreme learning machine (G-ELM) are proposed to train the GSLFNs acting on some metric spaces. The experimental results on some metric spaces indicate that GELM with additive/RBF hidden-nodes has a faster learning speed, a better accuracy, and a better stability than HPORBP algorithm and ν-GSVR for training the functional data. The idea of GELM can be used to extend those improved extreme learning machines (ELMs) that act on the Euclidean space ${\mathbb{R}^{n}, }$ such as online sequential ELM, incremental ELM, pruning ELM and so on, to some metric spaces. 相似文献
947.
Real-time and reliable measurements of the effluent quality are essential to improve operating efficiency and reduce energy consumption for the wastewater treatment process.Due to the low accuracy and unstable performance of the traditional effluent quality measurements,we propose a selective ensemble extreme learning machine modeling method to enhance the effluent quality predictions.Extreme learning machine algorithm is inserted into a selective ensemble frame as the component model since it runs much faster and provides better generalization performance than other popular learning algorithms.Ensemble extreme learning machine models overcome variations in different trials of simulations for single model.Selective ensemble based on genetic algorithm is used to further exclude some bad components from all the available ensembles in order to reduce the computation complexity and improve the generalization performance.The proposed method is verified with the data from an industrial wastewater treatment plant,located in Shenyang,China.Experimental results show that the proposed method has relatively stronger generalization and higher accuracy than partial least square,neural network partial least square,single extreme learning machine and ensemble extreme learning machine model. 相似文献
948.
Jiemei Zhao Zhonghui Hu Lijun Zhang 《International Journal of Control, Automation and Systems》2012,10(4):721-726
In this paper, a reliable H?? controller is designed for discrete-time singular systems with infinite distributed delays. Firstly, a stability criterion is obtained based on linear matrix inequality (LMI). Then a controller is designed to ensure the singular time-delay system to be regular, causal and stable with disturbance attenuation level ?? for possible actuator failures. A numerical example is given to illustrate the validity of the proposed approach. 相似文献
949.
Dihua Zhai Yu Kang Ping Zhao Yun-Bo Zhao 《International Journal of Control, Automation and Systems》2012,10(6):1182-1192
The stability of a class of switched stochastic nonlinear retarded systems with asynchronous switching controller is investigated. By constructing a virtual switching signal and using the average dwell time approach incorporated with Razumikhin-type theorem, the sufficient criteria for pth moment exponential stability and global asymptotic stability in probability are given. It is shown that the stability of the asynchronous stochastic systems can be guaranteed provided that the average dwell time is sufficiently large and the mismatched time between the controller and the systems is sufficiently small. This result is then applied to a class of switched stochastic nonlinear delay systems where the controller is designed with both state and switching delays. A numerical example illustrates the effectiveness of the obtained results. 相似文献
950.
This paper focuses on the problem of robust H ?? control of nonlinear switched systems with parameter uncertainty via the multiple Lyapunov functions (MLFs) approach. The uncertain parameters are assumed to be in a known compact set and are allowed to enter the system nonlinearly. Based on the explicit construction of Lyapunov functions, which avoids solving the Hamilton-Jacobi-Isaacs (HJI) inequalities, sufficient conditions for the solvability of the robust H ?? control problem of cascade nonlinear switched systems are derived under some switching signal. Then, the result is extended to solve the robust H ?? control problem of nonlinear switched systems in strict feedback form. Finally, the effectiveness of the proposed results is illustrated through a simulation example. 相似文献