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CSEE Journal of Power and Energy Systems 2022年第2期8卷 535-547页

作者： qiang Guo Lei Gao Xiaojie Chu Huadong sun China Electric Power Research Institute Beijing 100192China

A parameter estimation method based on an improved Whale Optimization Algorithm is proposed in this paper to identify the parameters of a static var compensator(SVC)***,a mathematical model of SVC is ***,the reverse learning strategy and Levy flight disturbance strategy are introduced to improve the whale optimization algorithm,and the improved whale optimization algorithm is applied to the parameter identification of the static var compensator ***,a stepwise identification method,by analyzing the local sensitivities of parameters,is proposed which solves the problem of low accuracy caused by multi-parameter *** method provides a new estimation strategy for accurately identifying the parameters of the static var compensator *** results show that the parameter estimation method can be an effective tool to solve the problem of parameter identification for the SVC model.

关键词： Local sensitivity analysis parameter estimation static var compensator model stepwise identification method whale Optimization Algorithm

Measured Impedance and Threshold Value of Electrode Line Impedance Supervision Based Protection in HVDC Transmission System

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Journal of Modern Power Systems and Clean Energy 2023年第4期11卷 1294-1304页

作者： qiang sun Bin Li Jiawei He Ye Li Key Laboratory of Smart Grid of Ministry of Education Tianjin UniversityTianjinChina State Key Laboratory of Reliability and Intelligence of Electrical Equipment Hebei University of TechnologyTianjinChina

At present,electrode line impedance supervision(ELIS)based protection is widely used to detect faults on grounding electrode lines,which are indispensable elements of high-voltage direct current(HVDC)*** existing theoretical analysis of measured impedance is based on lumped line model and the threshold value is generally set according to engineering experience,which have caused the dead zone problem and even ***,a study on measured impedance of ELIS-based protection and its threshold value selection method is carried out to solve this *** this study,the expressions of measured impedance under normal operation and fault conditions are deduced based on rigorous and accurate line *** on the expressions,the characteristics of the measured impedance are calculated and *** the characteristics of the measured impedance,the applicability of the protection with the traditional threshold value is further discussed and the distribution of the dead zone can be ***,the method to calculate the threshold value of ELIS-based protection is *** a proper threshold value selected by the proposed method,the dead zone of ELIS-based protection is effectively eliminated,and the protection can identify all types of faults even with large transition *** studies on PSCAD/EMTDC have been conducted to verify the conclusion.

关键词： Grounding electrode line electrode line impedance supervision(ELIS)based protection measured impedance characteristic threshold value selection

From ultra-low friction to superlubricity state of black phosphorus:Enabled by the critical oxidation and load

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Friction 2023年第10期11卷 1829-1844页

作者： qiang LI Fenghua SU Yanjun CHEN Jianfang sun School of Mechanical&Automotive Engineering South China University of TechnologyGuangzhou 510641China Guangdong Provincial Key Laboratory of Technique and Equipment for Macromolecular Advanced Manufacturing South China University of TechnologyGuangzhou 510640China

Based on the density functional theory(DFT),we investigate the friction properties of inevitable oxidized black phosphorus(o-BP).o-BP with the weaker interlayer adhesion exhibits their great potential as a solid *** the zero load,the friction property of o-BP is adjusted by its oxidation ***,ultra-low friction of P4O2(50%oxidation,O:P=2:4=50%)is obtained,which is attributed to the upper O atoms with lower sliding resistance in the O channel formed by lower layer O *** attractive,we observe superlubricity behavior of o-BP at the critical load/distance due to the flattening potential energy surface(PES).The flattening PES is controlled by the electrostatic role for the high-load(P4O3,O:P=3:4=75%),and by the electrostatic and dispersion roles for the low-load(P4O2).Distinctly,the transform from ultra-low friction to superlubricity state of black phosphorus(BP)can be achieved by critical oxidation and load,which shows an important significance in engineering *** addition,negative friction behavior of o-BP is a general phenomenon(Z>Z_(min),Z_(min)is the interlayer distances between the outermost P atoms of minimum load.),while its surface-surface model is different from the fold mechanism of the tip-surface model(Z_(0)Z_(min)).In summary,o-BP improves the friction performance and reduces the application limitation,comparing to graphene(Gr),MoS2,and their oxides.

关键词： oxidized black phosphorus(o-BP) ultra-low friction superlubricity critical load/distance first-principles

New Frequency Standard Comparison System Based on the Group Quantization Phase Processing

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Chinese Journal of Electronics 2019年第2期28卷 392-397页

作者： DU Baoqiang DENG Ran sun Xiyan FU qiang School of Electronic Information Engineering Zhengzhou University of Light Industry School of Information and Communication Guilin University of Electronic Technology

A new frequency standard comparison system is proposed based on the group quantization phase processing. By shortening the width of phase coincidence fuzzy area and capturing the best group phase coincidences, we reduce the randomness of the counting gate and improve the measurement precision of the comparison system. The method is based on the Fieldprogrammable gate array（FPGA）, which not only retains the advantage using phase synchronization detection technology to overcome the ±1-word counting error, but also accelerates the system response time, simplifies the measurement equipment, and reduces the development cost and power consumption. The experimental results show that the method is reasonable and scientific, and the comparison accuracy of the system can reach the E-12s;level, obviously superior to the measurement accuracy of the traditional frequency standard comparison method,which has a wide application and popularization value.

关键词： Frequency standard comparison Group quantization phase Greatest common factor period Phase group synchronization

Malvidin Mitigates Sepsis-induced Cardiac Injury by Modulating the TLR4-iNOS-COX-2 Inflammatory Pathway and the Bax/Bcl-2/Cyto-C Mitochondrial Apoptosis Pathway in a p38 MAPK-dependent Manner

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Biomedical and Environmental Sciences 2024年第2期37卷 221-227页

作者： ZHANG Wei YUAN Si Long qiang Jing Chao HUANG He LI Da sun Ying ZHANG hong Gang Department of Vascular Surgery The First People’s Hospital of LianyungangLianyungang 222005JiangsuChina Jiangsu Key Laboratory of Marine Pharmaceutical Compound Screening College of PharmacyJiangsu Ocean UniversityLianyungang 222005JiangsuChina Jinzhou Medical University postgraduate training base(Lianyungang First People’s Hospital) Lianyungang 222005JiangsuChina

In critical care medicine,sepsis is a dangerous systemic condition that is highly prevalent and is associated with high morbidity and mortality rates^([1]).The high mortality rate associated with sepsis is closely related to multi-organ dysfunction,with heart injury being particularly critical and considered the starting point of multi-organ injury^([2]).

关键词： mortality Apoptosis TLR4

Human prostate cancer stem cells： new features unveiled

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Asian Journal of Andrology 2011年第3期13卷 355-356页

作者： Yuting sun Wei-qiang Gao Department of Discovery Oncology Genentech Inc. South San Francisco CA 94080 USA Renji-MedX Clinical Stern Cell Research Center Renji Hospital Shanghai Jiao Tong University School of Medicine Shanghai 200127 China Med-X Research Institute Shanghai Jiao Tong University Shanghai 200030. China

Cancer stem cells （CSCs） are a rare subpopulation of phenotypically distinct cancer cells exhibiting stem cell characteristics. They are tumourigenic, meanwhile capable of self-renewal and forming differentiated progenies. CSCs are believed to be resistant to the standard therapeutics, and provide the cell reservoir for tumour initiation.1 Understanding CSCs or in another word, tumour-initiating cells, is of critical therapeutic importance.

关键词： Cells Lymphocytes Cancer (genus) Neoplasms Stems

Data-aided efficient synchronization for UWB signals based on minimum average error probability

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The Journal of China Universities of Posts and Telecommunications 2008年第1期15卷 6-10页

作者： sun qiang LU Tie-jun School of Information Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

One of the biggest challenges in ultra-wideband （UWB） radio is the accurate timing acquisition for the receiver. In this article, we develop a novel data-aided synchronization algorithm for pulses amplitude modulation （PAM） UWB systems Pilot and information symbols are transmitted simultaneously by an orthogonal code division multiplexing （OCDM） scheme. In the receiver, an algorithm based on the minimum average error probability （MAEP） of coherent detector is applied to estimate the timing offset. The multipath interference （MI） problem for timing offset estimation is considered. The mean-square-error （MSE） and the bit-error-rate（BER） performances of our proposed scheme are simulated. The results show that our algorithm outperforms the algorithm based on the maximum correlator output （MCO） in multipath channels.

关键词： timing offset estimation synchronization UWB,OCDM MAEP

Template-directed Synthesis of Carboxylic Acid-functionalized Tetracationic Cyclophane

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Chemical Research in Chinese Universities 2007年第6期23卷 745-748页

作者： XI Hai-tao sun Xiao-qiang CHEN Juan MENG Qi PAN Yi HU hong-wen Department of Chemistry Nanjing University Nanjing 210093 P. R. China Key Laboratory of Fine Chemical Engineering Jiangsu Polytechnic University Changzhou 213164 P. R. China

Introduction Although devices based on pseudorotaxanes, cantenanes, and rotaxanes are commercialized yet, several researches have been done on the applications of these donor-acceptor molecules. A promising area is the field of nanotechnology. The miniaturization of semi-conductor technology by the ＂top-down＂ approach is limited by the wavelength of the radiation used in the lithography to prepare electronic components. Therefore, the ＂bottom-up＂ may be more suitable to create devices with sizes down to the molecular level. A molecular or supramolecular system, in which the relative position of the component parts can be altered by an external stimulus, a molecular switch, can act as the basic unit for the creation of new molecular devices .

关键词： Ethyl 3,5-bis(bromomethyt) benzoate Cyetophane Template Synthesis

Information Flow Scheduling in Concurrent Multi-Product Development Based on DSM

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Chinese Journal of Mechanical Engineering 2017年第5期30卷 1101-1111页

作者： Qing-Chao sun Wei-qiang Huang Ying-Jie Jiang Wei sun School of Mechanical Engineering Dalian University of Technology

Multi-product collaborative development is adopted widely in manufacturing enterprise, while the present multi-project planning models don＇t take techni- cal/data interactions of multiple products into account. To decrease the influence of technical/data interactions on project progresses, the information flow scheduling models based on the extended DSM is presented. Firstly, infor- mation dependencies are divided into four types： series, parallel, coupling and similar. Secondly, different types of dependencies are expressed as DSM units, and the exten- ded DSM model is brought forward, described as a block matrix. Furthermore, the information flow scheduling methods is proposed, which involves four types of opera- tions, where partitioning and clustering algorithm are modified from DSM for ensuring progress of high-priority project, merging and converting is the specific computation of the extended DSM. Finally, the information flow scheduling of two machine tools development is analyzed with example, and different project priorities correspond to different task sequences and total coordination cost. The proposed methodology provides a detailed instruction for information flow scheduling in multi-product development, with specially concerning technical/data interactions.

关键词： Concurrent multi-product development Information flow planning Extended DSM Projectpriority

Distributing pairs of vertices on Hamiltonian cycles

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Science China Mathematics 2018年第5期61卷 955-972页

作者： Weihua He Hao Li qiang sun Department of Applied Mathematics Guangdong University of Technology Laboratoire de Recherche en Informatique CNRS-Université Paris-Sud Institute for Interdisciplinary Research Jianghan University School of Mathematical Science Yangzhou University

Let G be a graph of order n with minimum degree δ(G)≥n/2+1. Faudree and Li(2012) conjectured that for any pair of vertices x and y in G and any integer 2≤k≤n/2, there exists a Hamiltonian cycle C such that the distance between x and y on C is k. In this paper, we prove that this conjecture is true for graphs of sufficiently large order. The main tools of our proof are the regularity lemma of Szemer′edi and the blow-up lemma of Koml′os et al.(1997).

关键词： Hamiltonian cycle Faudree-Li conjecture regularity lemma blow-up lemma