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Science China(Information Sciences) 2018年第2期61卷 149-163页

作者： Xiaohui QI Kaizhi HUANG Bin LI Liang JIN Xinsheng JI National Digital Switching System engineering & technological research center School of Information and Electronics Beijing Institute of Technology

Cognitive heterogeneous cellular networks(CHCNs) are emerging as a promising approach to next-generation wireless communications owing to their seamless coverage and high network *** this paper, we describe our reliance on multi-antenna technology and a secrecy transmission protocol to ensure the reliability and security of downlink underlay CHCNs. First, we introduce a two-tier CHCN model using a stochastic geometry framework, and derive the probability distribution of the indicator function for a secrecy transmission scheme. We then investigate the connection outage probability, secrecy outage probability(SOP), and transmission SOP of both primary and cognitive users under a secrecy guard scheme and a threshold-based scheme. Furthermore, we reveal some insights into the secrecy performance by properly setting the predetermined access threshold and the radius of detection region for the secrecy transmission scheme. Finally, simulation results are provided to show the influence of the antenna system, eavesdropper density, predetermined access threshold, and radius of the detection region on the reliability and security performance of a CHCN.

关键词： cognitive heterogeneous cellular network physical layer security secrecy guard scheme threshold-based scheme multi-antenna technique

Analysis on Pseudo Excitation of Random Vibration for Structure of Time Flight Counter

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Chinese Journal of Mechanical engineering 2015年第2期28卷 325-330页

作者： WU Qiong LI Dapeng Beijing engineering technological research center of High-efficient & Green CNC Machining Process and Equipment Beihang University

Traditional computing method is inefficient for getting key dynamical parameters of complicated *** Excitation Method（PEM）is an effective method for calculation of random *** to complicated and coupling random vibration in rocket or shuttle launching,the new staging white noise mathematical model is deduced according to the practical launch *** deduced model is applied for PEM to calculate the specific structure of Time of Flight Counter（ToFC）.The responses of power spectral density and the relevant dynamic characteristic parameters of ToFC are obtained in terms of the flight acceptance test *** stiffness of fixture structure,the random vibration experiments are conducted in three directions to compare with the revised *** experimental results show the structure can bear the random vibration caused by launch without any damage and key dynamical parameters of ToFC are *** revised PEM is similar with random vibration experiment in dynamical parameters and responses are proved by comparative *** maximum error is within 9%.The reasons of errors are analyzed to improve reliability of *** research provides an effective method for solutions of computing dynamical characteristic parameters of complicated structure in the process of rocket or shuttle launching.

关键词： pseudo excitation method power spectral density random processes dynamic response vibration

Developing single nucleotide polymorphism(SNP)markers from transcriptome sequences for identification of longan(Dimocarpus longan)germplasm

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Horticulture research 2015年第1期2卷 325-334页

作者： Boyi Wang Hua-Wei Tan Wanping Fang Lyndel W Meinhardt Sue Mischke Tracie Matsumoto Dapeng Zhang yunnan Forestry technological College Kunming650224YunnanChina Sustainable Perennial Crops Laboratory USDA-ARSBeltsville Agricultural Research CenterBeltsville20705MDUSA College of Horticulture Nanjing Agricultural UniversityNanjing210095JiangsuChina Tropical Plant Genetic Resources and Disease research USDA-ARSHilo96720HIUSA

Longan(Dimocarpus longan Lour.)is an important tropical fruit tree *** varietal identification is essential for germplasm management and *** longan transcriptome sequences from public databases,we developed single nucleotide polymorphism(SNP)markers;validated 60 SNPs in 50 longan germplasm accessions,including cultivated varieties and wild germplasm;and designated 25 SNP markers that unambiguously identified all tested longan varieties with high statistical rigor(P<0.0001).Multiple trees from the same clone were verified and off-type trees were *** analysis revealed genetic relationships among analyzed *** varieties differed significantly from wild populations(Fst=0.300;P<0.001),demonstrating untapped genetic diversity for germplasm conservation and *** cultivated varieties,apparent differences between varieties from China and those from Thailand and Hawaii indicated geographic patterns of genetic *** SNP markers provide a powerful tool to manage longan genetic resources and breeding,with accurate and efficient genotype identification.

关键词： germplasm cultivated breeding

Molecular cloning and characterization of the endothelin 3 gene in black bone sheep

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Journal of Animal Science and Biotechnology 2018年第4期9卷 847-857页

作者： Hesham Y.A.Darwish Yuanyuan Zhang Kai Cui Zu Yang Deping Han Xianggui Dong Huaming Mao Weidong Deng Xuemei Deng National engineering Laboratory for Animal Breeding and Key Laboratory of Animal Genetics Breeding and Reproduction of the Ministry of AgricultureChina Agricultural University Animal Production research Institute Agricultural Research Center Ministry of Agriculture and Land Reclamation College of Veterinary Medicine China Agricultural University College of Animal Science and Technology Yunnan Agricultural University

Background: Black bone sheep was first discovered in yunnan province of China in 1970, with unique black pigmentation on the body and internal organs. Endothelin 3(EDN3) has been known as a key gene causing hyperpigmentation in black bone chicken, the Silky ***: In this study, EDN3 was employed as a candidate gene for regulating black color pigmentation. First,EDN3 was cloned from sheep to obtain the full-length cDNA by using the rapid amplification of cDNA ends(RACE).Genomic EDN3 was screened and a total of thirty predicted single nucleotide polymorphisms(SNPs) were genotyped for allele and genotype frequency analysis in a case-control study involving two black bone sheep populations. Genomic copy number analysis of EDN3 in sheep was conducted to measure the variation in copy number. EDN3 expression levels were observed among the groups in adult liver, lymph node, and kidney tissues, as well as embryo kidney samples. Also, among the tissues of black bone and non-black bone ***: The size of the full-length cDNA was 1,578 bp, which included 426 bp of 5′-untranslated region(5′-UTR),an open reading frame(ORF) of 639 bp encoding a protein of 212 amino acids, and a 3′-UTR of 513 bp. Genotype and allele frequencies of all the discovered SNPs were found insignificantly different in black bone and non-black bone sheep(P > 0.05). Genomic copy number analysis of EDN3 in sheep revealed no significant difference between the two sheep groups. No significant variations were found in the adult liver and kidney embryo samples. However,the expression in lymph node and kidney tissue was significantly higher in black bone sheep than that in non-black bone sheep(P < 0.05). Significant variations in the EDN3 expression levels were observed among the tissues of nonblack bone ***: The findings of the present study indicate that unlike in Silky chickens, EDN3 is not responsible for hyperpigmentation but may play a key functional role in immune and excretory

关键词： Black pigmentation Expression level Sequence analysis SNP

Robust secure transmission for multiuser MISO systems with probabilistic QoS constraints

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Science China(Information Sciences) 2016年第2期59卷 126-138页

作者： Lijian ZHANG Liang JIN Wenyu LUO Chunming WANG Yanqun TANG National Digital Switching System engineering & technological research center School of Information Systems engineering Zhengzhou Information Science and Technology Institute

This paper considers a unicast multiuser multiple-input single-output(MISO) downlink system overheard by multiple single-antenna eavesdroppers. The objective is to jointly design the beamforming vectors and the artificial noise(AN) covariance matrix with imperfect channel state information(CSI) at the transmitter,such that the total transmit power is minimized while satisfying probabilistic quality of service(Qo S) constraints at legitimate users and the eavesdroppers. Using Bernstein-type inequalities and the S-procedure, we recast the non-convex power minimization problem as two different convex semidefinite programs(SDPs) which can be solved using interior-point methods. Simulation results show that the proposed methods outperform a nonrobust method and the ones using the isotropic AN.

关键词： physical layer security artificial noise imperfect CSI robust beamforming semidefinite program outage probability

A Dynamic Protocol Stack Structure for Diversified QoS Requirements in Ad Hoc Network

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China Communications 2016年第S1期13卷 43-53页

作者： DONG Fang Li Ou RAN Xiaomin JIN Feicai National Digital Switching System engineering & technological research center Zhongxing Telecommunication Equipment Corporation

A dynamic protocol stack(DPS) for ad hoc networks, together with a protocol stack construction scheme that is modeled as a multiconstrained knapsack problem is proposed. Compared to the traditional static protocol stack, DPS operates in a dynamic and adaptive manner and is scalable to network condition changes. In addition, a protocol construction algorithm is proposed to dynamically construct of the protocol stack each network node. Simulation results show that, the processing and forwarding performance of our scheme is close to 1 Gb/s, and the performance of our algorithm is close to that of the classical algorithms with much lower complexity.

关键词： ad hoc network QoS guarantee dynamic protocol stack protocol construction algorithm

Secret Key Generation Based on Two-Way Randomness for TDD-SISO System

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China Communications 2018年第7期15卷 202-216页

作者： Shengjun Zhang Liang Jin Yangming Lou Zhou Zhong National Digital Switching System engineering&technological research center Zhengzhou 450002China

A novel secret key generation(SKG)method based on two-way randomness is proposed for TDD-SISO *** legitimate transceivers mutually transmit their own random signal via reciprocal wireless channel,then the multiplication of transmitted and received signal is used as common randomness to generate secret *** quasi-static channel,the theoretical SKG rates(SKGRs)of the three SKG methods,namely wireless channel based,one-way randomness and two-way randomness,are derived and ***,two practical SKG schemes based on twoway randomness,Scheme-1bit and Scheme-3bit,are completely designed and ***,Scheme-1bit applies to low signal to noise ratio(SNR)scenarios and achieves 0.13~0.86bit/T_s SKGR and 10^(-2)~10^(-5) level secret key outage probability(SKOP),while Scheme-3bit fits high SNR situation and obtains 0.93~1.35bit/T_s SKGR and 10^(-3)~10^(-4) level *** last,the national institute of standards and technology(NIST)test is conducted to evaluate the secret key randomness(SKRD)and the test results show that both of the proposed schemes have passed the test.

关键词： secret key generation physical layer security information reconciliation information theory

Distributed State and Fault Estimation for Cyber-Physical Systems Under DoS Attacks

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IEEE/CAA Journal of Automatica Sinica 2025年第1期 261-263页

作者： Limei Liang Rong Su Haotian Xu the School of Control Science and engineering Shandong University IEEE the School of Electrical and Electronic engineering Nanyang Technological University

Dear Editor,The letter deals with the distributed state and fault estimation of the whole physical layer for cyber-physical systems(CPSs) when the cyber layer suffers from DoS attacks. With the advancement of embedded computing, communication and related hardware technologies, CPSs have attracted extensive attention and have been widely used in power system, traffic network, refrigeration system and other fields.

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An Efficient Algebraic Solution for Moving Source Localization from Quadruple Hybrid Measurements

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Chinese Journal of Electronics 2022年第2期31卷 255-265页

作者： DING Ting ZHAO Yongsheng ZHAO Yongjun Henan High-Speed Railway Operation and technological research center PLA Strategic Support Force Information engineering University

This paper deals with the 3-D moving source localization using time difference of arrival(TDOA), frequency difference of arrival(FDOA), angle of arrival(AOA) and AOA rate measurements, gathered from a set of spatially distributed receivers. The TDOA,FDOA, AOA and AOA rate measurement equations were firstly established according to the space geometric relationship of the source relative to the receivers. Then an efficient closed-form algorithm for source position and velocity estimation from the quadruple hybrid measurements was proposed. The proposed algorithm converts the nonlinear measurement equations into a linear set of equations, which can then be used to estimate the source position and velocity applying weighted least square(WLS) minimization. In contrast to existing two-stage WLS algorithms, the proposed algorithm does not introduce any nuisance parameters and requires merely onestage, which enables for source localization with the fewest receivers necessary. Theoretical accuracy analysis shows that the proposed algorithm reaches the CramerRao lower bound, and simulation studies corroborate the efficiency and superiority of the proposed algorithm over other algorithms.

关键词： algebraic solution AOA rate measurement equations position measurement velocity estimation angle of arrival spatially distributed receivers Cramer-Rao lower bound source separation least squares approximations closed-form algorithm time difference of arrival two-stage WLS algorithms quadruple hybrid measurements time-of-arrival estimation source position weighted least square minimization frequency difference of arrival TDOA nonlinear measurement equations 3D moving source localization minimisation velocity measurement space geometric relationship direction-of-arrival estimation

Design by Analogy:Achieving More Patentable Ideas from One Creative Design

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Chinese Journal of Mechanical engineering 2018年第2期31卷 25-34页

作者： Li-Zhen Jia Chun-Long Wu Xue-Hong Zhu Run-Hua Tan Civil Aviation University of China Hebei University of Technology National engineering research center for technological Innovation Method and Tool

A patent is a kind of technical document to protect intellectual property for individuals or enterprises. Patentable idea generation is a crucial step for patent application and analogy is confirmed to be an effective technique to inspire creative ideas. Analogy?based design usually starts from representation of an analogy source and is followed by the retrieval of appropriate analogs, mapping of design knowledge and adaptation of target solution. To diffuse one core idea into other new contexts and achieve more patentable ideas, this paper mainly centered on the first two stages of analogy?based design and proposed a patentable ideation framework. The analogical information of the source system, including source design problems and solution, was mined comprehensively through International Patent Classification analysis and represented in the form of function, behavior and structure. Three heuristics were suggested for searching the set of candidate target systems with a similar design problem, where the source design could be transferred. To systematize the process of source representation, analogs retrieval, idea transfer, and solution generation, an ideation model was put forward. Finally, the bladeless fan was selected as a source design to illustrate the application of this work. The design output shows that the representation and heuristics are beneficial, and this systematic ideation method can help the engineer or designer enhance creativity and discover more patentable opportunities.

关键词： Design by analogy Patentable idea generation IPC analysis Idea transfer heuristics Bladeless fan