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A new feature extraction method using the amplitude fluctuation property of target HRRP for radar automatic target recognition

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Frontiers of Electrical and Electronic Engineering in China 2006年第2期1卷 171-176页

作者： DU Lan LIU Hong-wei bao zheng ZHANG Jun-ying National Laboratory of Radar Signal Processing Xidian UniversityXi'anShaanxi 710071China

Due to the aspect sensitivity of high-resolution range profile(HRRP),traditional radar HRRP target recognition methods usually use average profile within some target-aspect region as the target-aspect ***,the amplitude fluctuation property of target HRRP also represents some feature information of the *** on the scattering center model,a new feature extraction method using the amplitude fluctuation property of target HRRP is proposed in this *** weighted HRRP feature extracted by the new method can represent the scatterer distribution in every range cell,thereby it can describe the scattering property of the target *** experimental results based on measured data show that the new feature extraction method can greatly improve recognition performances.

关键词： Radar automatic target recognition(RATR) HRRP Feature extraction Scattering center model Average profile Variance profile

A smartcard conditional access interface scheme for conditional access subsystem separation in digital TV broadcasting

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第6期7卷 1008-1017页

作者： XIE Qiang zheng Shi-bao YU Xiao-jing Institute of lmage Communication and lnformation Processing Shanghai Jiao Tong University Shanghai 200240 China

Conditional access system (CAS) is a key technical component in digital TV broadcasting through which TV op-erators manage the appropriate rights of different subscribers in order to protect their commercial benefits. The normal digital TV receiver can only receive and decode the pay TV programs scrambled by one specific CAS. In this paper, the authors proposed a smartcard conditional access interface (SCAI) scheme in order to make the digital TV receiver be a common receiving platform independent of any specific CAS employed at the broadcasting head-end. As a result, it only needs to include a common condi-tional access software package (CCAP) without any requirement of hardware modification in the receiver. Comparison between the two mentioned DVB-CI-based schemes showed that the cost of such kind receiver is greatly reduced. The main design points of the proposed scheme and its reference implementation’s architecture are presented in this paper. This scheme is also one of the candidate national standards for Chinese digital TV broadcasting industry.

关键词： Digital TV broadcasting Conditional access subsystem separation Smartcard interface

Channel estimation in space and frequency domain for MIMO-OFDM systems

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The Journal of China Universities of Posts and Telecommunications 2009年第3期16卷 40-44页

作者： PAN Pei-sheng,zheng bao-yu College of Communication and Information,Nanjing University of Posts and Telecommunications,Nanjing 210003,China College of Communication and Information Nanjing University of Posts and Telecommunications Nanjing 210003 China

Multiple-input multiple-output （MIMO） systems can be combined with orthogonal frequency division multiplexing （OFDM） systems to improve the capacity and quality of wireless communications. In this article, a channel estimation technique in both space and frequency domain for MIMO-OFDM systems is proposed. It is shown that the proposed scheme with space-frequency pilot tones achieve optimal minimum mean square error （MMSE） channel estimation. Simulation results indicate that the proposed method achieves good performance.

关键词： channel estimation MIMO OFDM space frequency pilot tones

Mineral resource analysis by parabolic fractals

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Mining Science and Technology 2009年第1期19卷 91-96页

作者： XIE Shu-yun YANG Yong-guo bao zheng-yu KE Xian-zhong LILT Xiao-long State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Wuhan Hubei 430074 China Faculty of Earth Science China University of Geosciences Wuhan Hubei 430074 China Department of Geography York University Toronto ON M3J1P3 Canada School of Resources and Earth Sciences China University of Mining ＆ Technology Xuzhou Jiangsu 221116 China

Elemental concentration distributions in space have been analyzed using different approaches. These analyses are of great significance for the quantitative characterization of various kinds of distribution patterns. Fractal and multi-fractal methods have been extensively applied to this topic. Traditionally, approximately linear-fractal laws have been regarded as useful tools for characterizing the self-similarities of element concentrations. But, in nature, it is not always easy to find perfect linear fractal laws. In this paper the parabolic fractal model is used. First a two dimensional multiplicative multi-fractal cascade model is used to study the concentration patterns. The results show the parabolic fractal （PF） properties of the concentrations and the validity of non-linear fractal analysis. By dividing the studied area into four sub-areas it was possible to show that each part follows a non-linear parabolic fractal law and that the dispersion within each part varies. The ratio of the polynomial coefficients of the fitted parabolic curves can reflect, to some degree, the relative concentration and dispersal distribution patterns. This can provide new insight into the ore-forming potential in space. The parabofic fractal evaluations of ore-forming potential for the four suhareas are in good agreement with field investigation work and geochemical mapping results based on analysis of the original data.

关键词： parabolic fractal multiplicative multifractal cascade modeling ore-forming potential geochemical mapping

Short-term entecavir versus lamivudine therapy for HBeAg-negative patients with acute-on-chronic hepatitis B liver failure

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Hepatobiliary & Pancreatic Diseases International 2013年第2期12卷 154-159页

作者： Jing Lai Ying Yan Li Mai Yu-bao zheng Wei-Qiang Gan Wei-Min Ke Department of Infectious Diseases Third Affiliated Hospital Sun Yat-Sen University

BACKGROUND: Selection of drugs for antiviral therapy of patients with hepatitis B virus (HBV)-related acute-on-chronic liver failure (ACLF) remains difficult. This study was undertaken to evaluate the short-term efficacy of entecavir versus lamivudine on hepatitis B e antigen (HBeAg)-negative patients with ACLF. METHODS: The data of 182 HBeAg-negative patients with ACLF were retrospectively collected from patient profiles of the hospital. In these patients, 93 HBeAg-negative patients with ACLF were treated orally with 0.5 mg of entecavir and 89 were treated orally with 100 mg of lamivudine every day. The gender and age were matched between the two groups. Biochemical items, the model for end-stage liver disease (MELD) score, and HBV DNA level were matched at baseline between the two groups and monitored during treatment. The 3-month mortalities of the two groups were compared. RESULTS: No significant differences were found in biochemical items, MELD score, and HBV DNA level at baseline (P>0.05). HBV DNA level decreased within 3 months in both groups (P0.05). Pretreatment MELD score was not related to posttreatment HBV DNA levels (P>0.05), but related to a 3-month mortality in both groups (both P<0.001).CONCLUSIONS: In HBeAg-negative patients with ACLF, the short-term efficacy of entecavir versus lamivudine was similar. The degree of pretreatment liver failure significantly affected the outcome of treatment.

关键词： acute-on-chronic liver failure hepatitis B virus antiviral therapy clinical analysis

Ulcerative colitis with inflammatory polyposis in a teenage boy:A case report

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World Journal of Gastroenterology 2015年第3期21卷 1044-1048页

作者： Jin-Shan Feng Ying Ye Can-Can Guo Bo-Tao Luo Xue-bao zheng Research Institute of Traditional Chinese Medicine Guangdong Medical College Department of Gastroenterology Guangdong Medical College affiliated Lianjiang Hospital Department of Pathology School of Basic Medicine SciencesGuangdong Medical College

Ulcerative colitis in addition to inflammatory polyposis is *** benign sequel of ulcerative colitis can sometimes mimic colorectal *** report describes a rare case of inflammatory polyposis with hundreds of inflammatory polyps in ulcerative colitiswhich was not easy to distinguish from other polyposis syndromes.A 16-year-old Chinese male suffering from ulcerative colitis for 6 mo underwent colonoscopy,and hundreds of polyps were observed in the sigmoid,causing colonic *** polyps were restricted to the *** rectal inflammation was detected,no polyps were found in the rectum.A diagnosis of inflammatory polyposis and ulcerative colitis was *** patient underwent total colectomy and ileal pouch anal *** patient recovered well and was discharged on postoperative day *** surveillance after surgery is crucial as ulcerative colitis with polyposis is a risk factor for colorectal *** of polyposis requires clinical,endoscopic and histopathologic correlation,and helps with chemoprophylaxis of colorectal cancer,as the drugs used postoperatively for colorectal cancer,ulcerative colitis and polyposis are different.

关键词： Ulcerative colitis Inflammatory polyposis Teenager

位势问题改进的无网格局部Petrov-Galerkin法

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物理学报 2010年第8期59卷 5182-5189页

作者：郑保敬戴保东太原科技大学工程力学系太原030024

将滑动Kriging插值法与无网格局部Petrov-Galerkin法相结合,采用Heaviside分段函数作为局部弱形式的权函数,提出改进的无网格局部Petrov-Galerkin法,进一步将这种无网格法应用于位势问题,并推导相应的离散方程.因为滑动Kriging插值法构... 详细信息

将滑动Kriging插值法与无网格局部Petrov-Galerkin法相结合,采用Heaviside分段函数作为局部弱形式的权函数,提出改进的无网格局部Petrov-Galerkin法,进一步将这种无网格法应用于位势问题,并推导相应的离散方程.因为滑动Kriging插值法构造的形函数满足Kronecker函数性质,所以本文建立的改进的无网格局部Petrov-Galerkin法可以像有限元法一样直接施加边界条件;由于采用Heaviside分段函数作为局部弱形式的权函数,因此在计算刚度矩阵时只涉及边界积分,而没有区域积分.此外,还对本方法中一些重要参数的选取进行了研究.数值算例表明,本文建立的改进的无网格局部Petrov-Galerkin法具有数值实现简单、计算量小以及方便施加边界条件等优点.

关键词：无网格局部Petrov-Galerkin法滑动Kriging插值法无网格法位势问题

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基于危险理论的影像纹理调制模板的优化

测绘学报 2008年第1期37卷 49-53页

作者：郑宏郑肇葆武汉大学电子信息学院湖北武汉430079 武汉大学遥感信息工程学院湖北武汉430079

将危险理论引用到Bayesian Network技术产生纹理调制模板的方法中,解决应用Bayesian Network技术产生调制模板中不能保证纹理模板不断优化的问题。文中介绍危险区、危险信号的概念,并阐述怎样从危险区中找出有效数据的途径。详细介绍在... 详细信息

将危险理论引用到Bayesian Network技术产生纹理调制模板的方法中,解决应用Bayesian Network技术产生调制模板中不能保证纹理模板不断优化的问题。文中介绍危险区、危险信号的概念,并阐述怎样从危险区中找出有效数据的途径。详细介绍在基于Bayesian Network的模板优化中引入危险理论的思路、例证以及计算过程,并通过对实际航空影像纹理分类的试验证明了将危险理论应用于模板优化的有效性和优越性。

关键词：危险理论贝叶斯网络调制模板纹理影像分类

What MELD score mandates use of entecavir for ACLF-HBV HBeAg-negative patients?

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World Journal of Gastroenterology 2012年第33期18卷 4604-4609页

作者： Ying Yan Li Mai Yu-bao zheng Shao-Quan Zhang Wen-Xiong Xu Zhi-Liang Gao Wei-Min Ke Department of Infec-tious Diseases The Third Affiliated Hospital of Sun Yat-sen Uni-versity Guangzhou 510630 Guangdong Province China

AIM: To investigate optimal timing for therapeutic efficacy of entecavir for acute-on-chronic hepatitis B liver failure (ACLF-HBV) in hepatitis B e antigen (HBeAg)negative patients. METHODS: A total of 109 inpatients with ACLF-HBV were recruited from the Department of Infectious Diseases of the Third Affiliated Hospital, Sun Yat-sen University from October 2007 to October 2010. Entecavir 0.5 mg/d was added to each patient's comprehensive therapeutic regimen. Patients were divided into threegroups according to model for end-stage liver disease (MELD) score: high (≥ 30, 20 males and 4 females, mean age 47.8 ± 13.5 years); intermediate (22-30, 49 males and 5 females, 45.9 ± 12.4 years); and low (≤ 22, 28 males and 3 females, 43.4 ± 9.4 years). Statistical analysis were performed using SPSS 11.0 software. Data with normal distribution were expressed as mean ± SD and comparisons were made with Student's t tests. A value of P < 0.05 was considered statistically significant. Viral loads were related exponentially and logarithmic data were used for analysis. RESULTS: For 24 patients with MELD score ≥ 30, treatment lasted 17.2 ± 16.5 d. Scores before and after treatment were significantly different (35.97 ± 4.87 and 40.48 ± 8.17, respectively, t = -2.762, P = 0.011); HBV DNA load was reduced (4.882 ± 1.847 copies log10/mL to 3.685 ± 1.436 copies log10/mL); and mortality rate was 95.83% (23/24). Of 54 patients with scores of 22-30, treatment lasted for 54.0 ± 43.2 d; scores before and after treatment were 25.87 ± 2.33 and 25.82 ± 13.92, respectively (t = -0.030, P = 0.976); HBV DNA load decreased from 6.308 ± 1.607 to 3.473 ± 2.097 copies log10/mL; and mortality was 51.85% (28/54). Of 31 patients with scores ≤ 22, treatment lasted for 66.1 ± 41.9 d; scores before and after treatment were 18.88 ± 2.44 and 12.39 ± 7.80, respectively, (t = 4.860, P = 0.000); HBV DNA load decreased from 5.841 ± 1.734 to 2.657 ± 1.154 copies log10/mL; and mortality was 3.23% (1/31). CONCLUSION: Fo

关键词： Acute-on-chronic hepatitis B liver failure Hepatitis B e antigen negativity Entecavir Model for end-stage liver disease Mortality