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Science china(Information Sciences) 2011年第1期54卷 129-135页

作者： ZHOU ZhiQiang,LI ShaoQian & CHENG YuFan national key laboratory of Science and Technology on communications,University of Electronic Science and Technology of china,chengdu 610054,china national key laboratory of Science and Technology on communications University of Electronic Science and Technology of China Chengdu China

Fast frequency hopping can reduce the degradation caused by *** performance of noise-normalized fast frequency-hopped M-ary orthogonal frequency-shift-keying(FFH/MFSK)receivers over frequency nonselective Rayleigh fading channels with partial-band noise jamming is *** of numerical evaluation,a closed-form error probability expression is given based on the theory of complex variables. The simulation results validate the analytical *** is shown that there is an optimum diversity order and the system performance gets better with an increase in the modulation order.

关键词： anti-jamming fast frequency hopping noise normalization combining Rayleigh fading

An efficient quantum secret sharing protocol with orthogonal product states

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Science china(Physics,Mechanics & Astronomy) 2007年第3期50卷 331-338页

作者： YANG YuGuang1,2, WEN QiaoYan3 & ZHU FuChen4 1 School of Computer, Beijing University of Technology, Beijing 100022, china 2 State key laboratory of Information Security, Graduate University of Chinese Academy of Sciences, Beijing 100022, china 3 School of Science, Beijing University of Posts and Telecommunications, Beijing 100876, china 4.national key laboratory for modern communications, chengdu 61004., china School of Computer Beijing University of Technology Beijing China State key laboratory of Information Security Graduate University of Chinese Academy of Sciences Beijing China School of Science Beijing University of Posts and Telecommunications Beijing China national key laboratory for modern communications Chengdu China

An efficient quantum secret sharing protocol with orthogonal product states in the 33 Hilbert space is presented. The particles in the orthogonal product states form two particle sequences. One sequence is sent to Bob and the other is sent to Charlie after rearranging the particle orders. With the help of Alice, Bob and Charlie make the corresponding local measurement to obtain the information of the or- thogonal product states prepared. This protocol has many distinct features such as great capacity and high efficiency.

关键词： quantum secret sharing orthogonal product state orthogonal measurement

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An optimized non-unitary linear precoding design for OSTBCs

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Science china(Information Sciences) 2010年第2期53卷 335-343页

作者： HUANG HaiYang , WU Gang, LU Lu & LI ShaoQian national key laboratory of communications, University of Electronic Science and Technology of china, chengdu 610054, china national key laboratory of communications University of Electronic Science and Technology of China Chengdu China

This paper tackles the optimization of non-unitary linear precoding design for orthogonal spacetime block codes (OSTBCs). We dig out the transmission potentials by the analysis from eigen-space point of view according to the unique structure of OSTBCs. The proposed precoding form is proven to be theoretically optimized. Compared with the classical unitary Grassmannian codebook design, the non-unitary codebook further improves the overall performance of practical systems. The constraint on codebook size to guarantee full diversity order is given and proven. Based on this, we investigate the codebook construction method combined with a water-filling (WF) technique to reduce the impact of antenna correlation. The advantages of the novel design are verified via numerical simulations.

关键词： multi-antenna linear precoding OSTBCs non-unitary design antenna correlation

Performance analysis of peak cancellation in OFDM systems

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Science china(Information Sciences) 2012年第4期55卷 789-794页

作者： XIAO Yue,BAI WenLing,DAN LiLin,WU Gang & LI ShaoQian national key laboratory of Science and Technology on communications,University of Electronic Science and Technology of china,chengdu 610054,china national key laboratory of Science and Technology on communications University of Electronic Science and Technology of China Chengdu China

Peak cancellation is a class of peak-to-average power ratio (PAPR) reduction techniques for orthogo-nal frequency division multiplexing (OFDM).It can control the PAPR and out-of-band radiation simultaneously at the cost of additional *** this paper,the interference of peak cancellation is modeled and an-alyzed so as to evaluate the degradation of system ***,through theoretical analysis,a closed form of the BER performance is derived for OFDM with popular modulation schemes such as QPSK and ***,the analytical results are verified by simulations.

关键词： OFDM peak cancellation PAPR

A 2~n scaling scheme for signed RNS integers and its VLSI implementation

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Science china(Information Sciences) 2010年第1期53卷 203-212页

作者： MA Shang, HU JianHao, YE YanLong, ZHANG Lin & LING Xiang national key laboratory of Science and Technology on communications, University of Electronic Science and Technology of china, chengdu 611731, china national key laboratory of Science and Technology on communications University of Electronic Science and Technology of China Chengdu China

High effcient implementation of scaling in residue number system (RNS) is one of the critical issues for the applications of RNS in digital signal processing (DSP) systems. In this paper, an effcient scaling algorithm for signed integers in RNS is proposed firstly through introducing a correction constant in negative integers scaling procedure. Based on the proposed scaling algorithm, an effcient RNS 2n scaling implementation method is presented, in which Chinese remainder theorem (CRT) and a redundant modulus are used to perform the base extension to obtain the least significant n bits of RNS integers. With the redundant modulus, the RNS sign detection can be achieved by the parity detection. And then, an approach to update the residue digit of the redundant channel is also proposed. Meanwhile, this paper provides a method of computing the correction constant of the redundant channel in negative integers scaling. The analysis results indicate that the complexity of the proposed scaling algorithm grows linearly with the word-length of the RNS dynamic range without using Look-up Table (LUT). Furthermore, the proposed algorithm is employed for a specific moduli set 2n scaling. The synthesis results show that the critical path of the proposed algorithm is shortened by 12%, the area and power consumption performance is improved by about 35%, compared to the existing cascading 2n scaling method for very large scale integration (VLSI) implementation under the same restriction. Besides, the VLSI layout indicates that the parallel structure is simpler.

关键词： RNS VLSI scaling CRT base extension sign detection

Constructing globally consecutive 3D conductive network using P-doped biochar cotton fiber for superior performance of silicon-based anodes

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Journal of Materials Science & Technology 2024年第6期173卷 181-191页

作者： Jun Cao Jianhong Gao Kun Wang Zhuoying Wu Xinxin Zhu Han Li Min Ling chengdu Liang Jun Chen Zhejiang Provincial key laboratory of Advanced Chemical Engineering Manufacture Technology College of Chemical and Biological EngineeringZhejiang UniversityHangzhou 310027China Institute of Zhejiang University-Quzhou Zheda Road 99Quzhou 324000China

The inferior conductivity and drastic volume expansion of silicon still remain the bottleneck in achieving high energy density Lithium-ion Batteries(LIBs).The design of the three-dimensional structure of electrodes by compositing silicon and carbon materials has been employed to tackle the above challenges,however,the exorbitant costs and the uncertainty of the conductive structure persist,leaving ample room for ***,silicon nanoparticles were innovatively composited with eco-friendly biochar sourced from cotton to fabricate a 3D globally consecutive conductive *** network serves a dual purpose:enhancing overall electrode conductivity and serving as a scaffold to maintain electrode *** conductivity of the network was further augmented by introducing P-doping at the optimum doping temperature of 350℃.Unlike the local conductive sites formed by the mere mixing of silicon and conductive agents,the consecutive network can affirm the improvement of the conductivity at a macro ***,first-principle calculations further validated that the rapid diffusion of Li^(+)is attributed to the tailored electronic microstructure and charge rearrangement of the *** prepared consecutive conductive Si@P-doped carbonized cotton fiber anode outperforms the inconsecutive Si@Graphite anode in both cycling performance(capacity retention of 1777.15 mAh g^(-1) vs.682.56 mAh g^(-1) after 150 cycles at 0.3 C)and rate performance(1244.24 mAh g^(-1) vs.370.28 mAh g^(-1) at 2.0 C).The findings of this study may open up new avenues for the development of globally interconnected conductive networks in Si-based anodes,thereby enabling the fabrication of high-performance LIBs.

关键词： 3D conductive network Biochar carbon-silicon anode Heteroatoms doping strategy DFT calculation Lithium-ion battery

Cardiac nonrigid motion analysis from image sequences

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Progress in Natural Science:Materials International 2006年第10期16卷 1115-1118页

作者： LIU Huafeng (State key laboratory of modern Optical Instrumentation, Zhejiang University, Hangzhou 310027, china) State key laboratory of modern Optical Instrumentation Zhejiang University Hangzhou 310027 China

Noninvasive estimation of the soft tissue kinematics properties from medical image sequences has many important clinical and physiological implications, such as the diagnosis of heart diseases and the understanding of cardiac mechanics. In this paper, we present a biomechanics based strategy, framed as a priori constraints for the ill-posed motion recovery problems, to realize estimation of the cardiac motion and deformation parameters. By constructing the heart dynamics system equations from biomechanics principles, we use the finite element method to generate smooth estimates of heart kinematics throughout the cardiac cycle. We present the application of the strategy to the estimation of displacements and strains from in vivo left ventricular magnetic resonance image sequence.

关键词： cardiac motion and deformation continnum mechanics model finite element method.

Peculiar dynamical properties of plutonium hydrides

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Progress in Natural Science:Materials International 2006年第3期16卷 248-254页

作者： MENG Daqiao, ZHU Zhenghe, LUO Deli and JIANG Gang (Institute of Atomic and Molecular Physics, Sichuan University, chengdu 610065, china national key laboratory of Surface Physics and Chemistry, Mianyang 621907, china) Institute of Atomic and Molecular Physics Sichuan University Chengdu 610065 China national key laboratory of Surface Physics and Chemistry Mianyang 621907 China

In the present work, the structure and spectra of PuH and PuH2 are defined by B3LYP/SDD method, from which the analytic potential energy function of PuH2 is derived. The analysis of quasi-classical molecular reaction dynamics is performed to study the state-state process of Pu(7Fg) + H2(X1∑g+). It is found that the reaction Pu(7Fg)+H2(X1∑g+)→PuH2(X7B1) has no threshold. The simultaneous hydrogenation process of plutonium with the main product of PuH2 is theoretically proved for the first time.

关键词： hydrogenation reaction of plutonium molecular dynamics density functional theory.

Quantum threshold group signature

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Science china(Physics,Mechanics & Astronomy) 2008年第10期51卷 1505-1514页

作者： YANG YuGuang1,2,3 & WEN QiaoYan4 1 College of Computer Science and Technology, Beijing University of Technology, Beijing 100124, china 2 State key laboratory of Integrated Services Network, Xidian University, Xi’an 710071, china 3 State key laboratory of Information Security (Graduate University of Chinese Academy of Sciences), Beijing 100049, china 4 State key laboratory of Networking and Switching Technology, Beijing University of Posts and Tele-communications, Beijing 100876, china College of Computer Science and Technology Beijing University of Technology Beijing China State key laboratory of Integrated Services Network Xidian University Xi’an China State key laboratory of Information Security Graduate University of Chinese Academy of Sciences Beijing China State key laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing China

In most situations, the signer is generally a single person. However, when the message is written on behalf of an organization, a valid message may require the approval or consent of several persons. Threshold signature is a solution to this problem. Generally speaking, as an authority which can be trusted by all members does not exist, a threshold signature scheme without a trusted party appears more attractive. Following some ideas of the classical Shamir’s threshold signature scheme, a quantum threshold group signature one is proposed. In the proposed scheme, only t or more of n persons in the group can generate the group signature and any t-1 or fewer ones cannot do that. In the verification phase, any t or more of n signature receivers can verify the message and any t-1 or fewer receivers cannot verify the validity of the signature.

关键词： threshold quantum signature trusted party quantum cryptography

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Threshold proxy quantum signature scheme with threshold shared verification

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Science china(Physics,Mechanics & Astronomy) 2008年第8期51卷 1079-1088页

作者： YANG YuGuang1,3,4 & WEN QiaoYan2 1 College of Computer Science and Technology,Beijing University of Technology,Beijing 100124,china 2 State key laboratory of Networking and Switching Technology,Beijing University of Posts and Tele-communications,Beijing 100876,china 3 State key laboratory of Integrated Services Network,Xidian University,Xi’an 710071,china 4 State key laboratory of Information Security(Graduate University of Chinese Academy of Sciences) ,Beijing 100049,china College of Computer Science and Technology Beijing University of Technology Beijing China State key laboratory of Integrated Services Network Xidian University Xi’an China State key laboratory of Information Security (Graduate University of Chinese Academy of Sciences) Beijing China State key laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing China

A threshold proxy quantum signature scheme with threshold shared verification is proposed. An original signer could authorize a group as its proxy signers. Then only t or more of n persons in the proxy group can generate the proxy signature on behalf of the original signer and any t-1 or fewer ones cannot do that. When the proxy signature needs to be verified,any t or more of n persons belonging to the verification group can verify the message and any t-1 or fewer ones cannot verify the validity of the proxy signature.

关键词： quantum signature threshold proxy quantum group signature threshold shared verification

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