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Street-Level IP Geolocation Algorithm Based on Landmarks Clustering

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Computers, Materials & Continua 2021年第3期66卷 3345-3361页

作者： Fan Zhang Fenlin Liu Rui Xu Xiangyang Luo Shichang Ding Hechan Tian PLA strategic support force Information engineering university Zhengzhou450001China State Key Laboratory of Mathematical engineering and Advanced Computing Zhengzhou450001China Cyberspace Security Key Laboratory of Sichuan Province Chengdu610000China China Electronic Technology Cyber Security Co. Ltd.Chengdu610000China university of Goettingen Goettingen37075Germany

Existing IP geolocation algorithms based on delay similarity often rely on the principle that geographically adjacent IPs have similar ***,this principle is often invalid in real Internet environment,which leads to unreliable geolocation *** improve the accuracy and reliability of locating IP in real Internet,a street-level IP geolocation algorithm based on landmarks clustering is ***,we use the probes to measure the known landmarks to obtain their delay vectors,and cluster landmarks using ***,the landmarks are clustered again by their latitude and longitude,and the intersection of these two clustering results is taken to form training ***,we train multiple neural networks to get the mapping relationship between delay and location in each training ***,we determine one of the neural networks for the target by the delay similarity and relative hop counts,and then geolocate the target by this *** it brings together the delay and geographical coordinates clustering,the proposed algorithm largely improves the inconsistency between them and enhances the mapping relationship between *** evaluate the algorithm by a series of experiments in Hong Kong,Shanghai,Zhengzhou and New *** experimental results show that the proposed algorithm achieves street-level IP geolocation,and comparing with existing typical streetlevel geolocation algorithms,the proposed algorithm improves the geolocation reliability significantly.

关键词： IP geolocation neural network landmarks clustering delay similarity relative hop

Twenty-nine million intrinsic Q-factor monolithic microresonators on thin-film lithium niobate

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Photonics Research 2024年第8期12卷 I0001-I0006页

作者： XINRUI ZHU YAOWEN HU SHENGYUAN LU HANA KWARNER XUDONG LI YUNXIANG SONG LETÍCIA MAGALHÃES AMIRHASSAN SHAMS-ANSARI ANDREA CORDARO NEIL SINCLAIR MARKO LONČAR John A.Paulson School for engineering and Applied Sciences Harvard UniversityCambridgeMassachusetts 02138USA State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-optoelectronics School of PhysicsPeking UniversityBeijing 100871China DRS Daylight Solutions San DiegoCalifornia 92127USA

The recent emergence of thin-film lithium niobate(TFLN)has extended the landscape of integrated *** has been enabled by the commercialization of TFLN wafers and advanced nanofabrication of TFLN such as high-quality dry ***,fabrication imperfections still limit the propagation loss to a few dB/m,restricting the impact of this ***,we demonstrate TFLN microresonators with a record-high intrinsic quality(Q)factor of twenty-nine million,corresponding to an ultra-low propagation loss of 1.3 dB/*** present spectral analysis and the statistical distribution of Q factors across different resonator *** work pushes the fabrication limits of TFLN photonics to achieve a Q factor within 1 order of magnitude of the material limit.

关键词： resonator lithium film

Influence of phase shift drift and splitting ratio on 80 GHz optical mm-wave generation

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Optoelectronics Letters 2012年第4期8卷 301-305页

作者：朱子行赵尚弘幺周石谭庆贵李勇军董毅赵卫虎 Telecommunication engineering Institute Air Force Engineering University Key Laboratory of National Defence Science and Technology on space Microwave Technology

For the scheme of 80 GHz optical millimeter-wave(mm-wave) generation using two cascaded Mach-Zehnder modulators(MZMs),an exact analytical solution for the optical mm-wave affected by phase shift drift and splitting ratio is derived with the method of expanding Bessel *** results show that for the carrier and the fourth-order sideband,the influence caused by phase shift drift is dominant,while the first-order,the second-order and the third-order sidebands are influenced by both phase shift drift and splitting *** follows that the undesired sideband suppression ratio is at least 35.9 dB when the splitting ratio deviation is 0.001,and the phase shift drift is *** performance of the system is perfect if the accuracy is achieved.

关键词： Light modulators Millimeter waves Phase shift

Target maneuver trajectory prediction based on RBF neural network optimized by hybrid algorithm

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Journal of Systems engineering and Electronics 2021年第2期32卷 498-516页

作者： XI Zhifei XU An KOU Yingxin LI Zhanwu YANG Aiwu Aeronautics engineering College Air Force Engineering UniversityXi’an 710038China

Target maneuver trajectory prediction plays an important role in air combat situation awareness and threat *** solve the problem of low prediction accuracy of the traditional prediction method and model,a target maneuver trajectory prediction model based on phase space reconstruction-radial basis function(PSR-RBF)neural network is established by combining the characteristics of trajectory with time *** order to further improve the prediction performance of the model,the rival penalized competitive learning(RPCL)algorithm is introduced to determine the structure of RBF,the Levenberg-Marquardt(LM)and the hybrid algorithm of the improved particle swarm optimization(IPSO)algorithm and the k-means are introduced to optimize the parameter of RBF,and a PSR-RBF neural network is *** independent method of 3D coordinates of the target maneuver trajectory is proposed,and the target manuver trajectory sample data is constructed by using the training data selected in the air combat maneuver instrument(ACMI),and the maneuver trajectory prediction model based on the PSR-RBF neural network is *** order to verify the precision and real-time performance of the trajectory prediction model,the simulation experiment of target maneuver trajectory is *** results show that the prediction performance of the independent method is better,and the accuracy of the PSR-RBF prediction model proposed is *** prediction confirms the effectiveness and applicability of the proposed method and model.

关键词： trajectory prediction k-means improved particle swarm optimization(IPSO) Levenberg-Marquardt(LM) radial basis function(RBF)neural network

Node interdependent percolation of multiplex hypergraph with weak interdependence

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The Journal of China Universities of Posts and Telecommunications 2023年第6期30卷 49-59页

作者： Zhang Junjie Liu Caixia Liu Shuxin Zang Weifei Li Qian Institute of Information Technology PLA Strategic Support Force Information Engineering UniversityZhengzhou 450000China Institute of System engineering Academy of Military SciencesBeijing 100091China

In recent years, there has been considerable attention and research on the higher-order interactions that are prevalent in various real-world networks. Hypergraphs, especially in the study of complex systems, are proved effective in capturing these interactions. To better characterize the model in reality, this paper proposes a theoretical model of node interdependent percolation in multiplex hypergraphs, considering “weak” interdependence. The proposed model includes pairwise and higher-order interactions, where the removal of nodes triggers cascading failures. However, interdependent nodes connected to failed nodes experience partial loss of connections due to “weak” interdependence, reflecting the self-sustaining capabilities of real-world systems. Percolation theory is applied to the analysis to investigate the properties of the percolation threshold and phase transition. Both analysis and simulation results show that as the strength of interdependence between nodes weakens, the network transitions from a discontinuous to a continuous phase, thereby increasing its robustness.

关键词： node interdependent percolation theory hypergraph

ADVANCED COMPUTING AND ENDOGENOUS SECURITY

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China Communications 2021年第8期18卷 6-8页

作者： Hongchao Hu Zhen Ling Yuewu Wang Qi Li Liang Jin Jiangxing Wu NDSC 2. the School of Computer Science and engineering Southeast University 3. the Institute of Information Engineering at CAS 4. the Institute for Network Sciences and Cyberspace Tsinghua University 5. PLA Strategic Support Force Information Engineering University 6. the China National Academy with Engineering the National Digital Switching System engineering and Technological Research and Devel-opment Center (NDSC)

Computing is the foundation of cyberspace, and all activities in cyberspace are built on the basis of computing. At the same time, cyberspace and its underlying infrastructure are vulnerable to a wide range of risks stemming from both physical and cyber threats and hazards. With the further expansion of the scope of cyberspace, e.g., information technology being increasingly integrated with physical infrastructure operations, computing and security still considered as one of the least investigated and exploited regions. In the past years, significant progress has been made with respect to advanced computing and endogenous security theories and technologies, and commercial advanced computing and endogenous security devices and systems are anticipated to become a reality in the near future.

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A camouflage target detection method based on local minimum difference constraints

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Journal of Systems engineering and Electronics 2023年第3期34卷 696-705页

作者： GAN Yuanying LIU Chuntong LI Hongcai LIU Zhongye School of Missile engineering Rocket Force University of EngineeringXi’an 710025China

To address the problems of missing inside and incomplete edge contours in camouflaged target detection results,we propose a camouflaged moving target detection algorithm based on local minimum difference constraints(LMDC).The algorithm first uses the mean to optimize the initial background model,removes the stable background region by global comparison,and extracts the edge point set in the potential target region so that each boundary point(seed)grows along the center of the ***,we define the minor difference constraints term,combine the seed path and the target space consistency,and calculate the attributes of each pixel in the potential target area to realize camouflaged moving target *** algorithm of this paper is verified based on a public data sofa video and test videos and compared with the five classic *** experimental results show that the proposed algorithm yields good results based on integrity,accuracy,and a number of objective evaluation indexes,and its overall performance is better than that of the compared algorithms.

关键词： camouflage target detection moving target local contrast

Optimality Analysis of Sensor-Target Geometries for Bearing-Only Passive Localization in Three Dimensional space

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Chinese Journal of Electronics 2016年第2期25卷 391-396页

作者： ZHONG Yu WU Xiaoyan HUANG Shucai LI Chengjing WU Jianfeng Air and Missile Defense College Air Force Engineering University

Optimality analysis of sensor to target observation geometry for bearing-only passive localization is of practical significance in engineering and military applications and this paper generalized predecessors' researches in two-dimensions into three dimensional space. Based on the principles of Cramer-Rao lower bound(CRLB), Fisher information matrix(FIM) and the determinant of FIM derived by Cauchy-Binet formula, this paper configured the optimal observation geometry resulted from maximizing the determinant of FIM. Optimal observation geometry theorems and corresponding propositions were proved for N ≥ 2 sensors in three dimensions. One conjecture was proposed, i.e., when each range of N(N ≥ 4) sensors to the single target is identical, configuring the optimal geometry is equivalent to distributing N points uniformly on a unit sphere, which is one of the worldwide difficult problem. Studies in this paper can provide helpful reference for passive sensor deployment, route planning of detection platform and so on.

关键词： Bearing-only passive localization Optimal observation geometry Cramer-Rao lower bound(CRLB) Fisher information matrix(FIM) Distributing uniformly points on a Sphere conjecture

Chiral Pair Density Waves with Residual Fermi Arcs in RbV3Sb5

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Chinese Physics Letters 2024年第9期41卷 88-92页

作者： Xiao-Yu Yan Hanbin Deng Tianyu Yang Guowei Liu Wei Song Hu Miao Zhijun Tu Hechang Lei Shuo Wang Ben-Chuan Lin Hailang Qin Jia-Xin Yin Department of Physics Southern University of Science and TechnologyShenzhen 518055China Materials Science and Technology Division Oak Ridge National LaboratoryOak RidgeTennessee 37831USA Beijing Key Laboratory of Optoelectronic Functional Materials MicroNano Devices Department of PhysicsRenmin University of ChinaBeijing 100872China Key Laboratory of Quantum State Construction and Manipulation(Ministry of Education) Renmin University of ChinaBeijing 100872China Shenzhen Institute for Quantum Science and engineering Southern University of Science and TechnologyShenzhen 518055China Guangdong Provincial Key Laboratory of Quantum Science and engineering Southern University of Science and TechnologyShenzhen 518055China Quantum Science Center of Guangdong-Hong Kong-Macao Greater Bay Area Shenzhen 518055China

The chiral 2×2 charge order has been reported and confirmed in the kagome superconductor RbV3Sb5,while its interplay with superconductivity remains elusive owing to its lowest superconducting transition temperature Tc of about 0.85K in the AV3Sb5 family(A=K,Rb,Cs)that severely challenges electronic spectroscopic ***,utilizing dilution-refrigerator-based scanning tunneling microscopy down to 30 mK,we observe chiral 2×2 pair density waves with residual Fermi arcs in *** find a superconducting gap of 150eV with substantial residual in-gap *** spatial distribution of this gap exhibits chiral 2×2 modulations,signaling a chiral pair density wave(PDW).Our quasi-particle interference imaging of the zero-energy residual states further reveals arc-like *** discuss the relation of the gap modulations with the residual Fermi arcs under the space-momentum correspondence between PDW and Bogoliubov Fermi states.

关键词： Fermi chiral utilizing