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Linearly time-varying channel estimation and training power allocation for OFDM/MIMO systems using superimposed training

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Science china(Information Sciences) 2011年第7期54卷 1456-1470页

作者： ZHANG Han 1,DAI XianHua 2 & Pan DaRu 1 1 school of physics and Telecommunication engineering,South china Normal university,guangzhou 510006,china 2 department of Information Science and Technology,sun yat-sen university,guangzhou 510026,china 1. school of physics and Telecommunication engineering South China Normal University Guangzhou 510006 China2. Department of Information Science and Technology SUN Yat-sen University Guangzhou 510026 China

We address the problem of estimating the linearly time-varying (LTV) channel of orthogonal frequency division multiplexing (OFDM)/multiple-input multiple-output (MIMO) systems using superimposed training (ST).The LTV channel is modeled by truncated discrete Fourier *** on this model,a two-step approach is adopted to estimate the LTV channel over multiple OFDM *** also present performance analysis of the channel estimation and derive a closed-form expression for the channel estimation *** is shown that the estimation variances,unlike that of the conventional ST-based schemes,approach to a fixed lower-bound as the training length increases,which is directly proportional to information-pilot power *** wireless communication systems with a limited transmission power,we optimize the ST power allocation by maximizing the lower bound of the average channel *** results show that the proposed approach outperforms the frequency-division multiplexed training schemes.

关键词： OFDM/MIMO systems linearly time-varying channel estimation superimposed training training power allocation

Reflection of plane electromagnetic waves from the surface of a perfect conductor moving in an arbitrary direction

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Chinese Science Bulletin 2000年第17期45卷 1564-1569页

作者： HE Qicai & HUANG Yaoxiong1. department of physics, sun yat-sen university of Medical Sciences, guangzhou 510089, china 2. Institute of Biomedical engineering, Ji’nan university, guangzhou 510632, china Correspondence should be addressed to Huang Yaoxiong department of physics Sun Yat-sen University of Medical Sciences Guangzhou China Institute of Biomedical engineering Ji’nan University Guangzhou China

The reflection of plane electromagnetic waves (TE wave and TM wave) from a perfect conductor which moves in an arbitrary direction is investigated. Based on Maxwell’s equations and the boundary conditions for moving boundary, the relation between the field vectors of reflected and incident waves, and the reflection coefficient are derived. The energy balance between incident and reflected waves, the force exerted by electromagnetic waves to the moving conductor are also discussed and some new conclusions are suggested for notice.

关键词： plane electromagnetic wave moving conductor reflection coefficient radiation pressure.

Some basic principles for the linear theory of piezoelectric micropolar elastodynamics

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中国科学：物理学、力学、天文学英文版 2010年第6期53卷 1094-1100页

作者： luo En & LI WeiHua department of Applied Mechanics and engineering,sun yat-sen university,guangzhou 5102.5,china 1. department of Applied Mechanics and engineering Sun Yat-sen University Guangzhou 510275 China

According to the basic idea of classical yin-yang complementarity and modern dual-complementarity,in a simple and unified way proposed by luo,some basic principles in the linear theory of piezoelectric micropolar elastodynamics can be established systematically. In this paper,an important integral relation in terms of convolutions is given,which can be considered as the generalized principle of virtual work in mechanics. Based on this relation,it is not only possible to obtain the principle of virtual work and the reciprocal theorem,but also to systematically derive the complementary functionals for the eleven-field,nine-field and six-field simplified Gurtin-type variational principles and the potential energy-functional for the three-field one in the linear theory of piezoelectric micropolar elastodynamics by the generalized Legendre transformations given in this paper. Furthermore,with this approach,the intrinsic relationships among various principles can be explained clearly.

关键词： piezoelectric micropolar elastodynamics principle of virtual work reciprocal theorem simplified Gurtin-type variational principle complementary relation

Low-temperature Synthesis of Large-area Films of Molybdenum Trioxide Microbelts in Air and the Dependence of Their Field Emission Performance on Growth Conditions

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Journal of Materials Science & Technology 2010年第7期26卷 584-588页

作者： Dongmei Ban,Ningsheng Xu,Shaozhi Deng,Jun Chen and Juncong She State Key Lab of Optoelectronic Materials and Technologies,Guangdong Province Key Laboratory of Display Material and Technology,school of physics and engineering,sun yat-sen university,guangzhou 5102.5,china [a] State Key Lab of Optoelectronic Materials and Technologies Guangdong Province Key Laboratory of Display Material and Technology school of physics and engineering sun yat-sen university guangzhou 5102.5 china

A simple method is introduced for the preparation of large-area films of molybdenum trioxide （MoO3） microbelts. It is found that such films can be grown on indium tin oxide （ITO） glasses or silicon substrates at low temperatures by thermal evaporation deposition in air without using catalyst. Field emission measurements show that the turn-on field of the MoO3 microbelts is as low as 2.2 V/μm required to obtain a current density of 10 μA/cm^2, The combination of the simplicity of the growth method and the attractive field emission performance makes it a potential low-cost technique for the preparation of large-area field emission cold cathode material.

关键词： Field emission Large-area film Molybdenum trioxide Microstructures and synthesis

Stochastic resonance in the growth of a tumor induced bycorrelated noises

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Science Bulletin 2005年第20期 19-21页

作者： ZHONG Weirong, SHAO Yuanzhi & HE Zhenhui department of physics, sun yat-sen university, guangzhou 5102.5, china

Multiplicative noise is found to divide the growth law of tumors into two parts in a logistic model, which is driven by additive and multiplicative noises simul- taneously. The Fokker-Planck equation was also derived to explain the fact that the influence of the intensity of multi- plicative noise on the growth of tumor cells has a stochastic resonance-like characteristic. An appropriate intensity of multiplicative noise is benefit to the growth of the tumor cells. The correlation between two sorts of noises weakens the sto- chastic resonance-like characteristic. Homologous noises promote the growth of the tumor cells.

关键词： stochastic resonance multiplicative noise tumor logistic model correlation.

Local Electroretinogram and Pattern Visual Evoked Potential in Maculopathies

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Eye Science 1996年第1期16卷 40-45页

作者： De-zheng Wu, Guangwei luo, Yi HuangZhongshan Ophtalmic Center, sun yat-sen university of Medical Sciences, guangzhou 510050, china department of Ophthalmology, Xiang Fan Centre Hospital, Hubei 441021, china Zhongshan Ophtalmic Center Sun Yat-sen University of Medical Sciences Guangzhou China.

Purposes: To observe the characteristics of local electroretinogram (LERG) in normal subjects and patients with maculopathies, and to evaluate the applied worth of LERG and pattern visual evoked potential (PVEP) in maculopathies. Methods: LERGs at 5° and 15° macular regions were recorded from 27 normal subjects (54 eyes). The factors of age, different eyes and stimulate areas for LERG influence were observed. Meanwhile, the LERG and PVEP were recorded from 25 patients (35 eyes) with maculopathies for making contrast study. Results: In normal subjects, there was no significant influence of age to LERG. As the stimulated areas increased, the a- and b-wave amplitudes of LERG increased. In the patients with maculopathies, the a- and b-wave amplitudes of LERG at 5°, 10°and 15° macular regions were significantly lowered and the mean values of P1 latency were prolonged and N1-P1 amplitudes of VEP were lowered, comparing with the control group. In the nearing stimulated area (5°LERG and 14. 9×19°PVEP.),

关键词： maculopathy local electroretinogram (LERG) pattern visual evoked potential (PVEP)

Amplified circularly polarized luminescence of chiral metal-organic frameworks via post-synthetic installing pillars

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Chinese Chemical Letters 2024年第10期35卷 485-489页

作者： Xue-Zhi Wang Yi-Tong Liu Chuang-Wei Zhou Bei Wang Dong luo Mo Xie Meng-Ying sun Yong-Liang Huang jie luo Yan Wu Shuixing Zhang Xiao-Ping Zhou Dan Li department of Radiology The First Affiliated HospitalJinan UniversityGuangzhou 510632China College of Chemistry and Materials Science and Guangdong Provincial Key Laboratory of Functional Supramolecular Coordination Materials and ApplicationsJinanUniversityGuangzhou510632China department of Medicinal Chemistry Shantou University Medical CollegeShantou 515041China department of Anesthesiology The First Affiliated Hospital of Sun Yat-sen UniversityGuangzhou 50080China

Post-synthetic installation strategy is an effective approach to improve the functions of metal-organic frameworks(MOFs).Herein,a pair of chiral MOFs is successfully constructed through solvothermal subcomponent self-assembly and exhibit circularly polarized luminescence(CPL).These MOFs contain coordinatively unsaturated Zn sites and channels,which allow the installation of pyridyl-terminated pillars into the original *** a post-synthetic installation process reinforces the MOFs'rigidity and increases the photoluminescence quantum yields(PLQYs).Furthermore,the luminescence dissymmetry factors(glum)of these post-modified MOFs are amplified after installing the *** work provides an appealing strategy for boosting the CPL performance of chiral MOFs.

关键词： Chiral metal-organic frameworks Circularlypolarized luminescence Post-synthetic installation Pyridyl-terminated pillars Chirality transfer

Bound states and critical behavior of the Yukawa potential

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Science china(physics,Mechanics & Astronomy) 2006年第1期49卷 60-71页

作者： LI Yongyao1,luo xiangqian1 & Helmut Krōger2 1. department of physics,sun yat-sen university,guangzhou 5102.5,china 2.Département de Physique,Université Laval,Québec G1K 7P4,Canada 1. department of physics Sun Yat-sen University Guangzhou 510275 China 2. Département de Physique Université Laval Québec G1K 7P4 Canada

We investigate the bound states of the Yukawa potential V(r)=-λexp(-αr)/r, using different algorithms: solving the Schrodinger equation numerically and our Monte Carlo Hamiltonian approach. There is a critical α = αC, above which no bound state exists. We study the relation between αC and A for various angular momentum quantum number l. and find in atomic units, αC(l) = λ[A1 exp(-l/B1) + A2exp(-l/B2)], with A1 = 1.020(18), B1 = 0.443(14), A2 = 0.170(17), and B2 = 2.490(180).

关键词： Yukawa potential bound states critical behavior.

Expression of hepatitis B virus surface antigen in 120 Hodgkin's lymphoma patients

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Chinese Journal of Cancer 2010年第8期29卷 735-740页

作者： Miao-Zhen Qiu1,2, Dan-Yun Ruan1,2, Zhi-Qiang Wang1,2, Hui-Yan luo1,2, Kai-Yuan Teng1,2, Zhong-Jun Xia1,3, Yue Lu1,3, Hui-Qiang Huang1,2, Wen-Qi Jiang1,2, Rui-Hua Xu1,2 1 State Key Laboratory of Oncology in South china, sun yat-sen university Cancer Center, guangzhou, Guangdong 510060, P. R. china 2 department of Medical Oncology, sun yat-sen university Cancer Center, guangzhou, Guangdong 510060, P. R. china 3 department of Hematology Oncology, sun yat-sen university Cancer Center, guangzhou, Guangdong 510060, P. R. china sun yat-sen university Cancer Center State Key Laboratory of Oncology in South China Guangdong Guangzhou 510060

Background and Objective: Little is known about the incidence of hepatitis B virus (HBV) infection in Hodgkin's lymphoma patients. This study was to evaluate the impact of HBV infection on the survival of Hodgkin's lymphoma patient. Methods: Clinical data of 120 Hodgkin's lymphoma patients treated at the sun yat-sen university Cancer Center between January 2004 and October 2007 were collected. The impact of prognostic factors including HBV infection on survival was examined by univariate and multivariate analyses. A log-rank test was used for univariate analysis and the Cox proportional hazards regression model was used for multivariate analysis. Results: Of the 120 patients, 18 (15.0%) were hepatitis B virus surface antigen (HBsAg)-positive. The HBsAg-positive patients had lower 5-year survival rate than did the HBsAg-negative ones (66.9% vs. 91.3%, P = 0.006). When the patients were divided into early-stage (Ⅰ+Ⅱ) and advanced-stage (Ⅲ+Ⅳ) groups, the 5-year survival rate was significantly different between the HBsAg-positive and -negative patients in early-stage group (64.8% vs. 96.0%, P < 0.001), while not significantly different in advanced-stage group (75.0% vs. 84.8%, P=0.667). Both univariate and multivariate analyses showed that radiotherapy and HBV infection were independent prognosis factors for the patients with early-stage Hodgkin's lymphoma (P=0.006 and 0.014, respectively). Conclusions: The incidence of HBV infection is similar between Hodgkin's lymphoma patients and normal population. HBV infection is an independent prognosis factor for survival in the patients with early-stage Hodgkin's lymphoma.

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