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Strategic Analysis on Responding Human Avian Flu and Flu Pandemic in China

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Biomedical and Environmental Sciences 2006年第2期19卷 158-161页

作者： guang zeng Chinese Center for Disease Control and Prevention Beijing 100050 China

The 20th century has witnessed three global influenza pandemics attacking mankind, namely the 1918 Spanish pandemic （H1N1 subgroup）, the 1957 Asian pandemic （H2N2 subgroup） and the 1968 Hong Kong pandemic （H3N2 subgroup）. The first pandemic swept throughout the entire world within six to nine months, which affected 400 million people, accounting for 20% of the total world population, and 40 to 50 million deaths which were more than the total deaths in World War I, resulting the worst catastrophe in the history of human infectious diseases[1]. At the moment, the world is threatened by an avian influenza pandemic and people are concerned about a potential worldwide human influenza pandemic.

关键词： century Asian pandemic which affected

Classification of disturbance vectors for collision attack in SHA-1

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Science China(Information Sciences) 2015年第11期58卷 103-112页

作者： TANG YuChen zeng guang HAN WenBao The Information Engineering University

A good disturbance vector is one of the key techniques to find SHA-1 collisions and to construct valid differential paths. The main work of this paper is to classify the types of the optimal disturbance ***, we improve the EEM disturbance vectors search algorithm by Manuel. We increase the Hamming weight of information window from 4 to 6, with 244 time complexity, which is 28 times better than that of Manuel’s work. Based on this result, we prove that there are only two types of the optimal disturbance vectors, type-I and type-II, which have minimum weight of 25 in the last 60 of the 80 expanded words, in the total 2512 disturbance vectors searching space.

关键词： Hash function SHA-1 collision attack disturbance vector extended expanded message

高铁开通对工业技术效率的影响研究——基于市场可达性与集聚经济效应的分析

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山东财经大学学报 2025年第1期37卷 75-89页

作者：曾光宋安然路宇华中农业大学经济管理学院湖北武汉430070

中国高铁的快速发展降低了运输和交易成本,加速了要素流动,从而影响了地级及以上城市(以下简称地级市)的工业技术效率。基于2006—2020年259个地级市的面板数据,将市场可达性以及三种不同类型集聚外部性纳入同一框架,考察高铁开通对地... 详细信息

中国高铁的快速发展降低了运输和交易成本,加速了要素流动,从而影响了地级及以上城市(以下简称地级市)的工业技术效率。基于2006—2020年259个地级市的面板数据,将市场可达性以及三种不同类型集聚外部性纳入同一框架,考察高铁开通对地级市工业技术效率的直接、空间影响效应及其内在机制。研究发现:整体而言,尽管存在一定滞后效应,但地级市高铁开通可以显著提高其工业技术效率,且存在正向的空间溢出效应;高铁开通可以有效提高非区域中心城市工业技术效率,但对区域中心城市的提升效应不显著;机制分析结果表明,高铁开通能够有效提升地级市市场可达性、工业集聚专业化和竞争外部性,促进其技术效率的提升,但对多样化外部性具有显著负向影响,且结果具有较强的稳健性;与非区域中心城市相比,高铁开通对区域中心城市多样化外部性的影响不再显著。因此,各地应通过体制机制创新,优化要素配置,优化工业空间布局,引导、支持企业向工业园区等优势产地和市场区集聚,因地制宜地制定差异化的工业发展战略,放大高铁开通对地区工业技术效率的改善作用。

关键词：高铁开通集聚外部性市场可达性随机前沿方法工业技术效率

A new method for introduction ω-side chain of prostanoid using Barton radical reaction

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Chinese Chemical Letters 2009年第3期20卷 253-255页

作者： Yi Hua zeng guang Dian Han Institute of Materia Medica Peking Union Medical College Chinese Academy Medical Sciences Beijing 100050 China

A new method for introduction to-side chain of prostanoid was described in this note. Starting from acid chloride （3）, via Barton radical reaction, a trans α,β-unsaturated ketone sython was introduced.

关键词： Acid chloride N-Hydroxy-2-thiopyridine Barton ester ω-Side chain of prostanoid

Joint spatial-frequency blind multiuser detection based on LCCMA

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The Journal of China Universities of Posts and Telecommunications 2007年第2期14卷 19-22页

作者： ZHAO Fa-yong FENG guang-zeng Department of Communication and Information Engineering Nanjing University of Posts and Telecommunications Nanjing 210003 China

Multicarrier code division multiple access （MC-CDMA） has the ability to combat with frequency selective fading and antenna array can enhance the performance of system. The paper proposes a novel joint spatial-frequency blind multiuser detection for antenna array MC-CDMA based on linear constraint constant modulation algorithm （LCCMA）, which has robust performance and can ensue the weight vectors to converge to that of the desired user Simulation indicates the proposed algorithm has better bit error ratio （BER） performance than that of the traditional beamforming-based two-step algorithm.

关键词： antenna array MC-CDMA LCCMA joint spatial-frequency blind multiuser detection

Quantum Encryption Protocol Based on Continuous Variable EPR Correlations

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Communications in Theoretical Physics 2006年第1X期46卷 61-64页

作者： HE guang-Qiang zeng Gui-Hua The State Key Laboratory of Fibre-Optic Local Area Networks and Advanced Optical Communication Systems Depart-ment of Electronic Engineering Shanghai Jiao Tong University Shanghai 200030 China

A quantum encryption protocol based on Gaussian-modulated continuous variable EPR correlations is proposed. The security is guaranteed by continuous variable EPR entanglement correlations produced by nondegenerate optical parametric amplifier （NOPA）. For general beam splitter eavesdropping strategy, the mutual information I（α, ε） between Alice and Eve is caJculated by employing Shannon information theory. Finally the security analysis is presented.

关键词： quantum cryptography quantum encryption EPR correlations NOPA

A trinomial type of σ-LFSR oriented toward software implementation

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Science in China(Series F) 2007年第3期50卷 359-372页

作者： zeng guang HE KaiCheng HAN WenBao Department of Applied Mathematics Information Engineering University Zhengzhou 450002 China

In this paper, we introduce a new type of feedback shift register based on words, called G-linear feedback shift register （σ-LFSR） which can make full use of the instructions of modern CPUs so that we can find good σ-LFSR with simple structure and fast software implementation. After analysis, we find a class of simple σ-LFSR with maximal period and give an algorithm of searching for those σ-LFSRs. As a result, we provide a new optional fast component in the design of modern wordbased stream ciphers.

关键词： finite field stream cipher σ-LFSR primitive polynomial fast software implementation

Low-cost FPGA implementation of 2D digital pre-distorter for concurrent dual-band power amplifier

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The Journal of China Universities of Posts and Telecommunications 2016年第1期23卷 14-21页

作者： zeng guang Yu Cuiping Li Shulan Liu Yuan'an Beijing Key Laboratory of Work Safety Intelligent Monitoring Beijing University of Posts and Telecommunications School of Electronic Engineering Beijing University of Posts and Telecommunications

This paper proposes a low-cost hardware architecture based on concurrent dual-band digital pre-distorter （DPD）. The architecture is implemented on field programmable gate array （FPGA） to compensate for the nonlinearity of the concurrent dual-band power amplifier （PA）. This implementation introduces a novel model complexity reduction technique into system, namely, time-division multiplexing for out-of-band lookup tables （LUTs） sharing. Performances are evaluated with an experimental test setup using a wideband class-F PA. The dual-band signal center frequency separated by 80 MHz. Lower and upper center frequency are located at 2.61 GHz and 2.69 GHz, respectively. This novel DPD implementation maintains excellent performance, but uses hardware resources reduced by 29.17% compared with conventional approaches. The results show that the adjacent channel power ratio （ACPR） is less than -59 dBc and normalized mean square error （NMSE） is around - 62dB for lower sideband （LSB） and - 63dB for upper sideband （USB）.

关键词： power amplifier concurrent dual-band digital predistorter lookup table field programmable gate array (FPGA)

Automated Silicon-Substrate Ultra-Microtome for Automating the Collection of Brain Sections in Array Tomography

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IEEE/CAA Journal of Automatica Sinica 2021年第2期8卷 389-401页

作者： Long Cheng Weizhou Liu Chao Zhou Yongxiang Zou zeng-guang Hou the State Key Laboratory of Management and Control for Complex Systems Institute of AutomationChinese Academy of SciencesBeijing 100190 the School of Artificial Intelligence University of Chinese Academy of SciencesBeijing 100049China

Understanding the structure and working principle of brain neural networks requires three-dimensional reconstruction of brain tissue samples using array tomography *** order to improve the reconstruction performance,the sequence of brain sections should be collected with silicon wafers for subsequent electron microscopic ***,the current collection of brain sections based on silicon substrate involve mainly manual collection,which requires the involvement of automation techniques to increase collection *** paper presents the design of an automatic collection device for brain ***,a novel mechanism based on circular silicon substrates is proposed for collection of brain sections;second,an automatic collection system based on microscopic object detection and feedback control strategy is *** results verify the function of the proposed collection *** objects(brain section,left baffle,right baffle)can be detected from microscopic images by the proposed detection *** efficiency can be further improved with position feedback of brain sections *** has been experimentally verified that the proposed device can well fulfill the task of automatic collection of brain *** the help of the proposed automatic collection device,human operators can be partially liberated from the tedious manual collection process and collection efficiency can be improved.

关键词： Array tomography automatic collection system brain sections microscopic object detection serial section