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Spectrum sensing using multiple dual polarization antennas for cognitive radio systems in microcell environments

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Journal of Zhejiang University-Science C(Computers and electronics) 2013年第10期14卷 792-798页

作者： Yi-hu XU Myoung-Seob LIM division of electronics & Information Engineering Chonbuk National University

Spectrum sensing with multiple antennas for cognitive radio systems in microcell environments is affected by the spatial correlation among multiple *** reduce the adverse effects of the spatial correlation on the spectrum sensing performance,we employ multiple dual polarization antennas at the sensing node of secondary *** analysis of the spatial correlation is derived using the propagation characteristics of the electromagnetic wave based on the scattering patch model in a multipath microcell *** superiority of spectrum sensing with multiple dual polarized antennas over multiple mono-polarized antennas is shown by analyzing the false alarm and detection probabilities with the correlation among the antennas in a microcell environment.

关键词： Dual polarization Multiple antennas Spatial correlation Spectrum sensing Cognitive radio

Generalized passivity-based chaos synchronization

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Applied Mathematics and Mechanics(English Edition) 2010年第8期31卷 1009-1018页

作者： C.K.AHN Faculty of the division of electronics and Control Engineering Wonkwang University

In this paper, a new passivity-based synchronization method for a general class of chaotic systems is proposed. Based on the Lyapunov theory and the linear matrix inequality （LMI） approach, the passivity-based controller is presented to make the synchronization error system not only passive but also asymptotically stable. The proposed controller can be obtained by solving a convex optimization problem represented by the LMI. Simulation studies for the Genesio-Tesi chaotic system and the Qi chaotic system are presented to demonstrate the effectiveness of the proposed scheme.

关键词： passivity-based synchronization linear matrix inequality (LMI) chaotic systems Lyapunov theory

Finger vein recognition using weighted local binary pattern code based on a support vector machine

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Journal of Zhejiang University-Science C(Computers and electronics) 2010年第7期11卷 514-524页

作者： Hyeon Chang LEE Byung Jun KANG Eui Chul LEE Kang Ryoung PARK division of electronics and Electrical Engineering Dongguk University electronics and Telecommunications Research Institute division of Fusion and Convergence of Mathematical Sciences the National Institute for Mathematical Sciences

Finger vein recognition is a biometric technique which identifies individuals using their unique finger vein patterns. It is reported to have a high accuracy and rapid processing speed. In addition, it is impossible to steal a vein pattern located inside the finger. We propose a new identification method of finger vascular patterns using a weighted local binary pattern (LBP) and support vector machine (SVM). This research is novel in the following three ways. First, holistic codes are extracted through the LBP method without using a vein detection procedure. This reduces the processing time and the complexities in detecting finger vein patterns. Second, we classify the local areas from which the LBP codes are extracted into three categories based on the SVM classifier: local areas that include a large amount (LA), a medium amount (MA), and a small amount (SA) of vein patterns. Third, different weights are assigned to the extracted LBP code according to the local area type (LA, MA, and SA) from which the LBP codes were extracted. The optimal weights are determined empirically in terms of the accuracy of the finger vein recognition. Experimental results show that our equal error rate (EER) is significantly lower compared to that without the proposed method or using a conventional method.

关键词： Finger vein recognition Support vector machine (SVM) Weight Local binary pattern (LBP)

Chaos Synchronization of Nonlinear Bloch Equations Based on Input-to-State Stable Control

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Communications in Theoretical Physics 2010年第2期53卷 308-312页

作者： Choon Ki Ahn Faculty of the division of electronics and Control Engineering Wonkwang University

In this paper, we propose a new input-to-state stable （ISS） synchronization method for chaotic behavior in nonlinear Bloch equations with external disturbance. Based on Lyapunov theory and linear matrix inequality （LMI） approach, for the first time, the ISS synchronization controller is presented to not only guarantee the asymptotic synchronization but also achieve the bounded synchronization error for any bounded disturbance. The proposed controller can be obtained by solving a convex optimization problem represented by the LMI. Simulation study is presented to demonstrate the effectiveness of the proposed synchronization scheme.

关键词： chaos synchronization input-to-state stable (ISS) control nonlinear Bloch equations linear matrix inequality (LMI) Lyapunov theory

Configuration of propagator method for calculation of electron velocity distribution function in gas under crossed electric and magnetic fields

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Plasma Science and Technology 2019年第9期21卷 1-18页

作者： Hirotake SUGAWARA division of electronics for Informatics Graduate School of Information Science and TechnologyHokkaido University

This paper presents a self-contained description on the configuration of propagator method(PM)to calculate the electron velocity distribution function(EVDF) of electron swarms in gases under DC electric and magnetic fields crossed at a right angle. Velocity space is divided into cells with respect to three polar coordinates v,θ and f. The number of electrons in each cell is stored in three-dimensional arrays. The changes of electron velocity due to acceleration by the electric and magnetic fields and scattering by gas molecules are treated as intercellular electron transfers on the basis of the Boltzmann equation and are represented using operators called the propagators or Green’s functions. The collision propagator, assuming isotropic scattering, is basically unchanged from conventional PMs performed under electric fields without magnetic fields. On the other hand, the acceleration propagator is customized for rotational acceleration under the action of the Lorentz force. The acceleration propagator specific to the present cell configuration is analytically derived. The mean electron energy and average electron velocity vector in a model gas and SF6 were derived from the EVDF as a demonstration of the PM under the Hall deflection and they were in a fine agreement with those obtained by Monte Carlo simulations. A strategy for fast relaxation is discussed, and extension of the PM for the EVDF under AC electric and DC/AC magnetic fields is outlined as well.

关键词： propagator method electron velocity distribution function electron transport coefficients crossed electric and magnetic fields magnetized plasma Boltzmann equation

Multiple description scalable video coding based on 3D lifted wavelet transform

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第5期7卷 857-863页

作者： KIM Yong-deak division of electronics Engineering Ajou University Suwon 442-749 Korea

In this work, a new method to deal with the unconnected pixels in motion compensated temporal filtering (MCTF) is presented, which is designed to improve the performance of 3D lifted wavelet coding. Furthermore, multiple description scalable coding (MDSC) is investigated, and novel MDSC schemes based on 3D wavelet coding are proposed, using the lifting imple- mentation of temporal filtering. The proposed MDSC schemes can avoid the mismatch problem in multiple description video coding, and have high scalability and robustness of video transmission. Experimental results showed that the proposed schemes are feasible and adequately effective.

关键词： Multiple description scalable coding (MDSC), Motion compensated temporal filtering (MCTF), Block-split bidi-rectional motion estimation, 3D lifted wavelet transform

One- and two-photon absorption properties of two metalloporphyrin complexes

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Chinese Physics B 2011年第10期20卷 246-252页

作者：孙元红王传奎 Fundamental division of Shandong Police College College of Physics and electronics Shandong Normal University

The linear and nonlinear optical properties of two metalloporphyrin complexes formed by the complementary coordination of central zinc or magnesium ions to the ligand 5, 10, 15-tri-（p-tolyl）-20-phenylethynylporphyrin are theo- retically investigated by using the analytic response theory at the density functional theory level. The results indicate that the studied complexes present more symmetric geometry structures than the ligand. The charge-transfer states of the two complexes in the lower energy region are all almost degenerate but those of the ligand are well separated. The ratio of the two-photon absorption cross sections of the ligand, zinc-porphyrin and magnesium-porphyrin com- plexes is 1.0：1.5：1.8, demonstrating that the two-photon absorption capability can be greatly increased when the ligand is coordinated with a metal ion. Moreover, several physical micro-mechanisms including electron transitions and in- tramolecular charge-transfer processes are discussed to explore the differences in optical property between the ligand and two complexes.

关键词： two-photon absorption metalloporphyrin complexes analytic response theory

The theoretical studies on the two-photon absorption properties of symmetric l,4-bis{2-[4-(2-aryl)phenyl]vinyl}-2,5-bisdialkoxybenzenes

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Chinese Physics B 2010年第8期19卷 293-300页

作者：孙元红李龙禾李晶王传奎 Fundamental division of Shandong Police College College of Physics and electronics Shandong Normal University

On the level of the time-dependent hybrid density functional theory, the one- and two-photon absorption properties of a series of symmetric 4-bis{2-[4-（2-aryl） phenyl]vinyl）-2,5-bisdialkoxybenzenes are studied respectively utilizing the analytic response theory and the few-state model methods. The calculated results show that the planarity of the geometrical structure plays a great role in enhancing the linear and nonlinear optical abilities of the molecule. However the effect of the length of the chain linked to the π-centre on the optical property is very little. For the investigated compounds, the A-π-A type charge-transfer molecules display more superior one- and two-photon absorption characteristics than the D-π-D type ones. Furthermore, the two-photon absorption results by use of few-state model are generally consistent with those by analytic response theory, demonstrating the reliability of the few-state model for evaluating the two-photon absorption cross section. The numerical simulations are in good agreement in tendency with the available experimental measurements.

关键词： two-photon absorption analytic response theory few-state model

Two-photon absorption properties of aggregation systems on the basis of (E)-4-(2-nitrovinyl) benzenamine molecules

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Chinese Physics B 2010年第10期19卷 230-235页

作者：王传奎张珍丁明翠李小静孙元红赵珂 College of Physics and electronics Shandong Normal University Fundamental division Shandong Police College

Aggregation effect caused by the intermolecular hydrogen-bonding interactions on two-photon absorption prop- erties of （E）-4-（2-nitrovinyl） benzenamine molecules is studied at a hybrid density functional level. The geometry optimization studies indicate that there exist two probable conformations for the dimers and three for the trimers. A strong red-shift of the charge-transfer states is shown. The two-photon absorption cross sections of the molecule for certain conformations are greatly enhanced by the aggregation effect, from which a ratio of 1.0：2.6：3.6 is found for the molecule and its dimer and trimer with nearly planar structures. Namely, a 30 or 20 percent increase of the two-photon absorption cross section is observed.

关键词： two-photon absorption aggregate effect hydrogen bonding organic molecule