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Consistent and Accurate TDOA Localization in Dynamic NLOS Environments via Prior Information Independent Estimation

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China Communications 2024年第9期21卷 198-210页

作者： Luo Mei Long Yu Xiong Youzhi Qin Shuang key laboratory of Wireless Sensor Network in University of sichuan province College of Physics and Electronic EngineeringSichuan Normal UniversityChengdu 610101China

In the time-difference-of-arrival(TDOA)localization,robust least squares(LS)problems solved by mathematical programming were proven to be superior in mitigating the effects of non-line-of-sight(NLOS)***,the existing algorithms still suffer from two disadvantages:1)The algorithms strongly depend on prior information;2)The approaches do not satisfy the mean square error(MSE)optimal criterion of the measurement *** tackle the troubles,we first formulate an MSE minimization model for measurement noise by taking the source and the NLOS biases as *** obtain stable solutions,we introduce a penalty function to avoid abnormal *** further tackle the nonconvex locating problem with semidefinite relaxation ***,we incorporate mixed constraints and variable information to improve the estimation *** and experiments show that the proposed method achieves consistent performance and good accuracy in dynamic NLOS environments.

关键词： mathematical programming NLOS mitigation robust least squares TDOA

Electronic effects on radiation damage inα-iron:A molecular dynamics study

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Chinese physics B 2024年第3期33卷 521-529页

作者：江林李敏付宝勤崔节超侯氢 key laboratory for Radiation physics and Technology Institute of Nuclear Science and TechnologySichuan UniversityChengdu 610064China

Iron(Fe)-based alloys,which have been widely used as structural materials in nuclear reactors,can significantly change their microstructure properties and macroscopic properties under high flux neutron irradiation during operation,thus,the problems associated with the safe operation of nuclear reactors have been put forward *** this work,a molecular dynamics simulation approach combined with electronic effects is developed for investigating the primary radiation damage process inα-***,the influence of electronic effects on the collision cascade in Fe is systematically evaluated based on two commonly used interatomic potentials for *** simulation results reveal that both electronic stopping(ES)and electron-phonon coupling(EPC)can contribute to the decrease of the number of defects in the thermal spike *** application of ES reduces the number of residual defects after the cascade evolution,whereas EPC has a reverse *** introduction of electronic effects promotes the formation of the dispersive subcascade:ES significantly changes the geometry of the damaged region in the thermal spike phase,whereas EPC mainly reduces the extent of the damaged ***,the incorporation of electronic effects effectively mitigates discrepancies in simulation outcomes when using different interatomic potentials.

关键词： radiation damage electronic effects molecular dynamics simulation α-iron

The biochemical behavior and mechanism of uranium(Ⅵ)bioreduction induced by natural Bacillus thuringiensis

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Journal of Environmental Sciences 2024年第2期136卷 372-381页

作者： Shunzhang Chen Junyuan Gong Yanxia Cheng Yuqi Guo Feize Li Tu Lan Yuanyou Yang Jijun Yang Ning Liu Jiali Liao key laboratory of Radiation physics and Technology of the Ministry of Education Institute of Nuclear Science and TechnologySichuan UniversityChengdu 610064China

For a broader understanding of uranium migration affected by microorganisms in natural anaerobic environment,the bioreduction of uranium(Ⅵ)(U(Ⅵ))was revealed in Bacillus thuringiensis,a dominant bacterium strain with potential of uranium-tolerant isolated from uranium contaminated *** reduction behavior was systematically investigated by the quantitative analysis of U(Ⅳ)in bacteria,and mechanism was inferred from the pathway of electron *** anaerobic conditions,appropriate biomass and sodium lactate as electron donor,reduction behavior of U(Ⅵ)induced by *** was restricted by the activity of lactate dehydrogenase,which was directly affected by the initial pH,temperature and initial U(Ⅵ)concentration of bioreduction *** of U(Ⅵ)was driven by the generation of nicotinamide adenine dinucleotide(NADH)from enzymatic reaction of sodium lactate with various *** transmission of the electrons from bacteria to U(Ⅵ)was mainly supported by the intracellular NADH dehydrogenase-ubiquinone system,this process could maintain the biological activity of cells.

关键词： Uranium Bacillus thuringiensis Bioreduction Electron transmission

Orbital-Ordering Driven Simultaneous Tunability of Magnetism and Electric Polarization in Strained Monolayer VCl_(3)

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Chinese physics Letters 2024年第4期41卷 126-131页

作者：郭的坪王聪王侣锦陆赟豪吴骅张妍宁季威 Beijing key laboratory of Optoelectronic Functional Materials&Micro-Nano Devices Department of PhysicsRenmin University of ChinaBeijing 100872China key laboratory of Quantum State Construction and Manipulation(Ministry of Education) Renmin University of ChinaBeijing 100872China Zhejiang province key laboratory of Quantum Technology and Device State Key Laboratory of Silicon MaterialsDepartment of PhysicsZhejiang UniversityHangzhou 310027China laboratory for computational Physical Sciences(MOE) State Key Laboratory of Surface Physicsand Department of PhysicsFudan UniversityShanghai 200433China Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaChengdu 610054China

Two-dimensional(2D)van der Waals magnetic materials have promising and versatile electronic and magnetic properties in the 2D limit,indicating a considerable potential to advance spintronic *** predictions thus far have not ascertained whether monolayer VCl_(3) is a ferromagnetic(FM)or anti-FM monolayer;this also remains to be experimentally *** theoretically investigate the influence of potential factors,including C_(3) symmetry breaking,orbital ordering,epitaxial strain,and charge doping,on the magnetic ground *** first-principles calculations,we predict a collinear type-Ⅲ FM ground state in monolayer VCl_(3) with a broken C_(3) symmetry,wherein only the former two of three t_(2g)orbitals(a_(1g),e_(g2)^(π)and e_(g1)^(π))are *** atomic layer thickness and bond angles of monolayer VCl_(3) undergo abrupt changes driven by an orbital ordering switch,resulting in concomitant structural and magnetic phase *** doping to the underlying Cl atoms of monolayer VCl_(3) without C_(3) symmetry simultaneously induces in-and out-of-plane *** can achieve a multiferroic phase transition if combined with the discovered adjustments of magnetic ground state and polarization magnitude under *** establishment of an orbital-ordering driven regulatory mechanism can facilitate deeper exploration and comprehension of magnetic properties of strongly correlated systems in monolayer VCl_(3).

关键词： monolayer symmetry orbital

Cooperative activation of sodium channels for downgrading the energy efficiency in neuronal information processing

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Chinese physics B 2024年第5期33卷 758-763页

作者：严浩然颜家琦俞连春邵玉峰 School of Physical Science and Technology Lanzhou Center for Theoretical PhysicsLanzhou UniversityLanzhou 730000China key laboratory of Theoretical physics of Gansu province and Key Laboratory of Quantum Theory and Applications of MoELanzhou UniversityLanzhou 730000China Department of Neuroscience AnatomyHistologyand EmbryologyKey Laboratory of Preclinical Study for New Drugs of Gansu ProvinceSchool of Basic Medical SciencesLanzhou UniversityLanzhou 730000China

The Hodgkin–Huxley model assumes independent ion channel activation,although mutual interactions are common in biological *** raises the problem why neurons would favor independent over cooperative channel *** this study,we evaluate how cooperative activation of sodium channels affects the neuron’s information processing and energy *** of the stochastic Hodgkin–Huxley model with cooperative activation of sodium channels show that,while cooperative activation enhances neuronal information processing capacity,it greatly increases the neuron’s energy *** a result,cooperative activation of sodium channel degrades the energy efficiency for neuronal information *** discovery improves our understanding of the design principles for neural systems,and may provide insights into future designs of the neuromorphic computing devices as well as systematic understanding of pathological mechanisms for neural diseases.

关键词： energy efficiency ion channel noise action potential generation neuronal dynamics

Construct a 3D microsphere of HMX/B/Al/PTFE to obtain the high energy and combustion reactivity

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Defence Technology（防务技术） 2024年第2期32卷 45-54页

作者： Jian Wang Jie Chen Yaofeng Mao Yongjun Deng Wei Cao Fude Nie Jun Wang Institute of Chemical Materials China Academy of Engineering PhysicsMianyang 621999PR China Shock and Vibration of Engineering Materials and Structures key Lab of sichuan province Mianyang 621010PR China

Metal(aluminum and boron)based energetic materials have been wildly applied in various fields including aerospace,explosives and micro-devices due to their high energy ***,the low combustion efficiency and reactivity of metal fuels,especially boron(B),severely limit their practical ***,multi-component 3D microspheres of HMX/B/Al/PTFE(HBA)have been designed and successfully prepared by emulsion and solvent evaporation method to achieve superior energy and combustion *** reactivity and energy output of HBA are systematically measured by ignitionburning test,constant-volume explosion vessel system and bomb *** to the increased interfacial contact and reaction area,HBA shows higher flame propagation rate,faster pressurization rate and larger combustion heat of 29.95 cm/s,1077 kPa/s,and 6164.43 J/g,which is 1.5 times,3.5 times,and 1.03 times of the physical mixed counterpart(HBA-P).Meanwhile,HBA also shows enhanced energy output and reactivity than 3D microspheres of HMX/B/PTFE(HB)resulting from the high reactivity of *** reaction mechanism of 3D microspheres is comprehensively investigated through combustion emission spectral and thermal analysis(TG-DSC-MS).The superior reactivity and energy of HBA originate from the surface etching of fluorine to the inert shell(Al_(2)O_(3) and B_(2)O_(3))and the initiation effect of Al to *** work offers a promising approach to design and prepare high-performance energetic materials for the practical applications.

关键词： HMX/B/Al/PTFE 3D microspheres Surface etching Reaction mechanism

Enhanced Privacy-Preserving WiFi Fingerprint Localization from CL Encryption

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Chinese Journal of Electronics 2024年

作者： Zhiwei WANG Qiuchi ZHU Zhenqi ZHANG School of Computer Nanjing University of Posts and Telecommunications State key laboratory of Public Big Data Guizhou University Advanced Cryptography and System Security key laboratory of sichuan province Chengdu University of Information Engineering key laboratory of computational Science and Application of Hainan province Hainan Normal University

The WiFi fingerprint-based localization method is considered one of the most popular techniques for indoor localization. In INFOCOM'14, Li et al. proposed a WiFi fingerprint localization system based on Paillier encryption, which is claimed to protect both client C' s location privacy and service provider S's database ***, Yang et al. presented a practical data privacy attack in INFOCOM'18, which allows a polynomial time attacker to obtain S's database. We propose a novel WiFi fingerprint localization system based on CL(CastagnosLaguillaumie) encryption, which has a trustless setup and is efficient due to the excellent properties of CL *** prevent Yang et al.'s attack, the system requires that S selects only the locations from its database that can receive the nonzero signals from all the available APs in C ' s nonzero fingerprint in order to determine C 's location. Security analysis shows that our scheme is secure under Li et al.'s threat model. Furthermore, to enhance the security level of PriWFLCL, we propose a secure and efficient zero-knowledge proof protocol for the discrete logarithm relations in C 's encrypted localization queries.

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Train-induced aerodynamic characteristics of vertical sound barriers influenced by several factors

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Railway Engineering Science 2024年第2期32卷 177-193页

作者： Xiaowei Qiu Xiaozhen Li Jing Zheng Ming Wang State key laboratory of Bridge Intelligent and Green Construction Southwest Jiaotong UniversityChengdu 611756SichuanChina Wind Engineering key laboratory of sichuan province Southwest Jiaotong UniversityChengdu 611756SichuanChina School of Architecture and Civil Engineering West Anhui UniversityLu’anAnhuiChina

Investigations into the aerodynamic properties of vertical sound barriers exposed to high-speed operations employ computational fluid *** primary focus of this research is to evaluate the influence of train speed and the distance(D)from the track centerline under various operating *** findings elucidate a marked elevation in the aerodynamic effect amplitude on sound barriers as train speeds *** single-train passages,the aerodynamic effect amplitude manifests a direct relationship with the square of the train *** two trains pass each other,the aerodynamic amplitude intensifies due to an additional aerodynamic increment on the sound *** increment exhibits an approximate quadratic correlation with the retrograde train ***,the impact of high-speed trains on sound barrier aerodynamics surpasses that of low-speed trains,and this discrepancy amplifies with larger speed differentials between ***,the train-induced aerodynamic effect diminishes significantly with greater distance(D),with occurrences of pressure coefficient(CP)exceeding the standard thresholds during dual-train *** study culminates in the formulation of universal equations for quantifying the influence of train speed and distance(D)on sound barrier aerodynamic characteristics across various operational scenarios.

关键词： Aerodynamic characteristic Sound barrier Two trains passing each other Distance from track centerline CFD simulation

Efficient privacy-preserving federated learning under dishonest-majority setting

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Science China(Information Sciences) 2024年第5期67卷 323-324页

作者： Yinbin MIAO Da KUANG Xinghua LI Tao LENG Ximeng LIU Jianfeng MA School of Cyber Engineering Xidian University Intelligent Policing key laboratory of sichuan province Sichuan Police College Institute of Information Engineering Chinese Academy of Sciences School of Cyber Security University of Chinese Academy of Sciences key laboratory of Information Security of Network Systems Fuzhou University

Federated learning(FL) is an emerging distributed learning paradigm that solves the problem of isolated data by jointly learning the global model through distributed ***, recent studies have shown that FL may not always guarantee sufficient privacy preservation, this is mainly because the model parameters(e.g., weights or gradients)may leak sensitive information to malicious adversaries.

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