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A Novel Anti-Collision Algorithm for Large Scale of UHF RFID Tags Access Systems

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Computers, Materials & Continua 2024年第7期80卷 897-912页

作者： Xu zhang yi He Haiwen yi Yulu zhang Yuan Li shuai Ma Gui Li Zhiyuan Zhao yue liu Junyang liu Guangjun wen Jian Li School of Information and Communication Engineering/yibin Institute University of Electronic Science and Technology of ChinaChengdu611731China Department of IoT Technology Research China Mobile Research InstituteBeijing100053China The 10th Research Institute of China Electronics Technology Group Corporation Chengdu611731China College of Information and Communication National University of Defense TechnologyWuhan430019China

When the radio frequency identification(RFID)system inventories multiple tags,the recognition rate will be seriously affected due to *** on the existing dynamic frame slotted Aloha(DFSA)algorithm,a sub-frame observation and cyclic redundancy check(CRC)grouping combined dynamic framed slotted Aloha(SUBF-CGDFSA)algorithm is *** algorithm combines the precise estimation method of the quantity of large-scale tags,the large-scale tags grouping mechanism based on CRC pseudo-randomcharacteristics,and the Aloha anti-collision optimization mechanism based on sub-frame *** grouping tags and sequentially identifying themwithin subframes,it accurately estimates the number of remaining tags and optimizes frame length accordingly to improve efficiency in large-scale RFID *** outcomes demonstrate that this proposed algorithmcan effectively break through the system throughput bottleneck of 36.8%,which is up to 30%higher than the existing DFSA standard scheme,and has more significant advantages,which is suitable for application in largescale RFID tags scenarios.

关键词： Radio frequency identification anti-collision tags grouping dynamic framed slotted Aloha

TransTM:A device-free method based on time-streaming multiscale transformer for human activity recognition

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Defence Technology（防务技术） 2024年第2期32卷 619-628页

作者： yi liu Weiqing Huang Shang Jiang Bobai Zhao shuai wang Siye wang Yanfang zhang Institute of Information Engineering Chinese Academy of Sciences School of Cyber SecurityUniversity of Chinese Academy of SciencesBeijingChina School of Information Management Beijing Information Science and Technology UniversityBeijingChina

RFID-based human activity recognition(HAR)attracts attention due to its convenience,noninvasiveness,and privacy *** RFID-based HAR methods use modeling,CNN,or LSTM to extract features ***,they have shortcomings:1)requiring complex hand-crafted data cleaning processes and 2)only addressing single-person activity recognition based on specific RF *** solve these problems,this paper proposes a novel device-free method based on Time-streaming Multiscale Transformer called *** model leverages the Transformer's powerful data fitting capabilities to take raw RFID RSSI data as input without ***,we propose a multiscale convolutional hybrid Transformer to capture behavioral features that recognizes singlehuman activities and human-to-human *** with existing CNN-and LSTM-based methods,the Transformer-based method has more data fitting power,generalization,and ***,using RF signals,our method achieves an excellent classification effect on human behaviorbased classification *** results on the actual RFID datasets show that this model achieves a high average recognition accuracy(99.1%).The dataset we collected for detecting RFID-based indoor human activities will be published.

关键词： Human activity recognition RFID Transformer

Passive IoT Localization Technology Based on SD-PDOA in NLOS and Multi-Path Environments

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Computers, Materials & Continua 2024年第7期80卷 913-930页

作者： Junyang liu Yuan Li Yulu zhang shuai Ma Gui Li yi He Haiwen yi yue liu Xiaotao Xu Xu zhang Jinyao He Guangjun wen Jian Li School of Information and Communication Engineering/yibin Institute University of Electronic Science and Technology of ChinaChengdu611731China Department of IoT Technology Research China Mobile Research InstituteBeijing100053China The 10th Research Institute of China Electronics Technology Group Corporation Chengdu611731China College of Information and Communication National University of Defense TechnologyWuhan430019China

Addressing the challenges of passive Radio Frequency Identification(RFID)indoor localization technology in Non-Line-of-Sight(NLoS)and multipath environments,this paper presents an innovative approach by introducing a combined technology integrating an improved Kalman Filter with Space Domain Phase Difference of Arrival(SD-PDOA)and Received Signal Strength Indicator(RSSI).This methodology utilizes the distinct channel characteristics in multipath and NLoS contexts to effectively filter out interference and accurately extract localization information,thereby facilitating high precision and stability in passive RFID *** efficacy of this approach is demonstrated through detailed simulations and empirical tests conducted on a custom-built experimental platform consisting of passive RFID tags and an R420 *** findings are significant:in NLoS conditions,the four-antenna localization system achieved a notable localization accuracy of 0.25 m at a distance of 5 *** complex multipath environments,this system achieved a localization accuracy of approximately 0.5 m at a distance of 5 *** compared to conventional passive localization methods,our proposed solution exhibits a substantial improvement in indoor localization accuracy under NLoS and multipath *** research provides a robust and effective technical solution for high-precision passive indoor localization in the Internet of Things(IoT)system,marking a significant advancement in the field.

关键词： Indoor localization multipath and NLoS environments combined SD-PDOA and RSSI technology

Magnetic NiFe_(2)O_(4)@FeNi_(3)core-shell nanospheres derived from FeNi-LDH precursor anchoring on rGO nanosheets for enhanced electromagnetic wave absorption

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Journal of Materials Science & Technology 2024年第4期171卷 101-114页

作者： Kunyao Cao Yuan Fang shuai wang yue zhang Jiayue wen Jun Chen Rui Zhao Weidong Xue School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 610054China

Graphene has been extensively utilized in the domain of electromagnetic wave(EMW)absorption ma-terials because of its excellent electrical ***,the inferior impedance matching per-formance and the single loss mechanism vastly restrict the ***,it’s an effective strat-egy to solve these issues by introducing magnetic ***,layer double hydroxide(LDH)is an appropriate template to obtain magnetic component *** that ferromagnetic met-als such as Fe,Co,Ni,and their corresponding metal oxides are usually treated as magnetic compo-nents which are promising candidates for EMW absorption ***,in this work,a FeNi-layered double hydroxide-reduced graphene oxide(FeNi-LDH-rGO)aerogel was synthesized through a series of processes such as electrostatic self-assembly,hydrothermal,freeze-drying,and *** magnetic NiFe_(2)O_(4)@FeNi_(3)core-shell nanospheres were obtained from FeNi-LDH precursor,anchoring on rGO nanosheets after the annealing ***,the effects of different mass ratios of LDH to GO as well as different annealing temperatures of LDH-rGO aerogel on the EMW absorption prop-erty and impedance matching performance were *** a consequence,the fabricated ultralight 600LDH-rGO 2:1 aerogel shows a broad effective absorption bandwidth(EAB)of 7.04 GHz at a thickness of 2.3 mm with a low filling content of only 6 wt%and a low density of 4.4 mg/cm^(3).In conclusion,the synthetic LDH-rGO aerogels offer an effective strategy for preparing EMW absorption materials that own three-dimensional porous network structure and unique magnetic NiFe_(2)O_(4)@FeNi_(3)core-shell struc-ture nanospheres.

关键词： Electrostatic self-assembly Electromagnetic wave absorption LDH-rGO aerogel Layered double hydroxide Reduced graphene oxide NiFe_(2)O_(4)@FeNi_(3)core-shell structure

FOXO1 reshapes neutrophils to aggravate acute brain damage and promote late depression after traumatic brain injury

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Military Medical Research 2024年第4期11卷 521-542页

作者： Mi Zhou Yang-Wu-yue liu Yu-Hang He Jing-Yu zhang Hao Guo Hao wang Jia-Kui ren yi-Xun Su Teng Yang Jia-Bo Li wen-Hui He Peng-Jiao Ma Man-Tian Mi shuang-shuang Dai Department of Biochemistry and Molecular Biology School of Basic MedicineArmy Medical UniversityChongqing 400038China Research Center for Nutrition and Food Safety Chongqing Key Laboratory of Nutrition and HealthInstitute of Military Preventive MedicineArmy Medical UniversityChongqing 400038China Department of Neurosurgery Daping HospitalArmy Medical UniversityChongqing 400042China Department of Trauma and Emergency Southwest HospitalArmy Medical UniversityChongqing 400038China Department of Histology and Embryology Chongqing Key Laboratory of NeurobiologyBrain and Intelligence Research Key Suyixun Laboratory of Chongqing Education CommissionArmy Medical UniversityChongqing 400038China Research Center Seventh Affiliated Hospital of Sun Yat-Sen UniversityShenzhen 518107GuangdongChina

Background:Neutrophils are traditionally viewed as first responders but have a short onset of action in response to traumatic brain injury(TBI).However,the heterogeneity,multifunctionality,and time-dependent modulation of brain damage and outcome mediated by neutrophils after TBI remain poorly ***:Using the combined single-cell transcriptomics,metabolomics,and proteomics analysis from TBI patients and the TBI mouse model,we investigate a novel neutrophil phenotype and its associated effects on TBI outcome by neurological deficit scoring and behavioral *** also characterized the underlying mechanisms both invitro and invivo through molecular simulations,signaling detections,gene expression regulation assessments[including dual-luciferase reporter and chromatin immunoprecipitation(ChIP)assays],primary cultures or co-cultures of neutrophils and oligodendrocytes,intracellular iron,and lipid hydroperoxide concentration measurements,as well as forkhead box protein O1(FOXO1)conditional knockout ***:We identified that high expression of the FOXO1 protein was induced in neutrophils after TBI both in TBI patients and the TBI mouse *** of these FOXO1high neutrophils in the brain was detected not only in the acute phase but also in the chronic phase post-TBI,aggravating acute brain inflammatory damage and promoting late TBI-induced *** the acute stage,FOXO1 upregulated cytoplasmic Versican(VCAN)to interact with the apoptosis regulator B-cell lymphoma-2(BCL-2)-associated X protein(BAX),suppressing the mitochondrial translocation of BAX,which mediated the antiapoptotic effect companied with enhancing interleukin-6(IL-6)production of FOXO1high *** the chronic stage,the“FOXO1-transferrin receptor(TFRC)”mechanism contributes to FOXO1high neutrophil ferroptosis,disturbing the iron homeostasis of oligodendrocytes and inducing a reduction in myelin basic protein,which contributes to the progression of late depression afte

关键词： Traumatic brain injury(TBI) Neutrophil Forkhead box protein O1(FOXO1) Acute stage Chronic stage

Identification and immune analysis of antimicrobial peptides from the cigarette beetle(Lasioderma serricorne)

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Insect Science 2024年第4期31卷 1121-1134页

作者： yue zhang yi Yan Guy Smagghe Hong Yang ren-huai Dai wen-jia Yang Guizhou Provincial Key Laboratory for Agricultural Pest Management of the Mountainous Region Institute of EntomologyGuizhou UniversityGuiyangChina Guizhou Provincial Key Laboratory for Rare Animal and Economic Insect of the Mountainous Region College of Biology and Environmental EngineeringGuiyang UniversityGuiyangChina

Antimicrobial peptides(AMPs)in insects are endogenous peptides that are effector components of the innate defense system of the *** may serve as antimicrobial agents because of their small molecular weight and broad-spectrum antimicrobial *** this study,we performed transcriptome analysis of cigarette beetle(Lasioderma serricorne)larvae,parasitized by the ectoparasitic wasp,Anisopteromalus *** AMP genes were significantly upregulated following *** parasitism,postulating the hypothesis that the parasitization enhanced the host's resistance against pathogenic microorganisms through the regulation of host AMP ***,3 AMP genes(LsDef1,LsDef2,and LsCole)were significantly upregulated and we studied their immune function in *** challenge and functional analysis showed that LsCole was responsible for the immune response against Gram-negative and Gram-positive bacteria,while LsDef1 and LsDef2 were involved in insect defense against Gram-positive *** recombinant LsCole exhibited antimicrobial activities against the Gram-negative bacterium Escherichia coli and the Gram-positive bacterium Staphylococcus ***2 showed an antibacterial effect against *** and LsDef2 exhibited antibiofilm activity against *** 2 AMPs disrupted cell membranes and caused leakage of *** cell *** results indicated that the 3 AMPs in *** are involved in the innate immunity of this pest *** AMPs may have potential as antimicrobial agents for bacterial infection ***,data are discussed in relation to new control strategies with greater biosafety against pest insects with use of microbial biocontrol agents in combination with RNA interference against the insect's defensive AMP genes.

关键词： antimicrobial activity antimicrobial peptides innate immune response Lasioderma serricorne RNA interference

Vibration Control of the Rail Grinding Vehicle with Abrasive Belt Based on Structural Optimization and Lightweight Design

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Chinese Journal of Mechanical Engineering 2024年第3期37卷 311-337页

作者： wengang Fan shuai zhang Zhiwei Wu yi liu Jiangnan Yu School of Mechanical Electronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China Key Laboratory of Vehicle Advanced Manufacturing Measuring and Control TechnologyMinistry of EducationBeijing 100044China China Railway Materials Operation and Maintenance Technology Co. LtdBeijing 100036China

As a new grinding and maintenance technology,rail belt grinding shows significant advantages in many applications The dynamic characteristics of the rail belt grinding vehicle largely determines its grinding performance and service *** order to explore the vibration control method of the rail grinding vehicle with abrasive belt,the vibration response changes in structural optimization and lightweight design are respectively analyzed through transient response and random vibration simulations in this ***,the transient response simulation analysis of the rail grinding vehicle with abrasive belt is carried out under operating conditions and non-operating ***,the vibration control of the grinding vehicle is implemented by setting vibration isolation elements,optimizing the structure,and increasing ***,in order to further explore the dynamic characteristics of the rail grinding vehicle,the random vibration simulation analysis of the grinding vehicle is carried out under the condition of the horizontal irregularity of the American AAR6 ***,by replacing the Q235 steel frame material with 7075 aluminum alloy and LA43M magnesium alloy,both vibration control and lightweight design can be achieved *** results of transient dynamic response analysis show that the acceleration of most positions in the two working conditions exceeds the standard value in GB/T 17426-1998 *** optimizing the structure of the grinding vehicle in three ways,the average vibration acceleration of the whole car is reduced by about 55.1%from 15.6 m/s^(2) to 7.0 m/s^(2).The results of random vibration analysis show that the grinding vehicle with Q235 steel frame does not meet the safety conditions of 3σ.By changing frame material,the maximum vibration stress of the vehicle can be reduced from 240.7 MPa to 160.0 MPa and the weight of the grinding vehicle is reduced by about 21.7%from 1500 kg to 1175 *** modal analysis results indic

关键词： Vibration control Dynamic characteristics Structural optimization Lightweight design Modal analysis

Influence of vibration on the lubrication effect of a splash-lubricated gearbox

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第4期25卷 324-339页

作者： yi liu Kailin zhang shuai SHAO Hongxu XIANG Zhijian YE State Key Laboratory of Rail Transit Vehicle System Southwest Jiaotong UniversityChengdu 610031China

In this study,we investigate the effect of rail vibrations on the lubrication and efficiency of a splash-lubricated gearbox;specifically,the gearbox of a rail-transit vehicle.A high-fidelity 3D numerical model of the gearbox in a moving reference system is described,as well as computational fluid dynamics(CFD)simulations of the gearbox with different vibration *** effects of rotational speed,oil-immersion depth,and different oil-injection volume rates on lubrication and efficiency are *** propose a method of evaluating the internal lubrication condition of a splash-lubricated gearbox and quantitatively compare the effects of different operating parameters on lubrication and ***,our experiment to verify the feasibility of the simulation method is *** results show that with vibration,the churning loss and oil supply for the bearings are significantly higher than those under static *** addition,among different vibrational directions,lateral vibration has the greatest influence on the lubrication condition and efficiency of the *** the studied railway-vehicle gearbox,the best lubrication condition is achieved at a rotational speed of 1600 r/min and an oil-immersion depth of two times the tooth height(***).Rotational speed is the operating parameter that has the most significant effect on the lubrication and efficiencyofthegearbox.

关键词： Comprehensive lubrication evaluation Churning loss Moving reference system Splash lubrication Vibrational excitation Gearbox

Assessment on gas-polyethylene terephthalate solid interface partial discharge properties of C4F7N/CO_(2)gas mixture for eco-friendly gas insulating transformer

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High Voltage 2024年第1期9卷 35-45页

作者： Song Xiao yifan wang Chenhua ren Haoran Xia yue Zhao Jingzi Qin Xiaoxing zhang yi Luo yi Li State Key Laboratory of Power Grid Environmental Protection School of Electrical Engineering and AutomationWuhan UniversityWuhanHubeiChina Beijing International S&T Cooperation Base for Plasma Science and Energy Conversion Institute of Electrical EngineeringChinese Academy of SciencesBeijingChina State Grid Anhui Electric Power Company Anhui Electric Power Research Institute HefeiAnhuiChina Hubei Engineering Research Center for Safety Monitoring of New Energy and Power Grid Equipment School of Electrical and Electronic EngineeringHubei University of TechnologyWuhanHubeiChina

The eco-friendly insulating gas perfluoroisobutyronitrile(C_(4)F_(7)N)is potentially used in gas-insulated transformers(GIT)to replace sulphur hexafluoride(SF_(6)).However,evaluation of the long-term insulation reliability and gas–solid interface discharge decomposition characteristics of the gas–solid film insulation structure in GIT is *** authors simulated the gas–solid film insulation structure in GIT and explored the interface partial discharge(PD)characteristics of C4F7N/CO_(2)gas mixture with polyethylene terephthalate(PET).The effect of gas pressure,mixing ratio on gas–solid interface gas decomposition,PET degradation was investigated,and the interaction mechanism was *** is found that the interface PD generated three degradation regions on a PET *** gas–solid interface reaction in the electrode contact region and the discharge development trace was significantly higher than that of halation *** content of gas decomposition products decreases with the increase of gas pressure and the PD intensity of SF6-PET is inferior to that of C_(4)F_(7)N/CO_(2)under the same *** results provide reference for the development and application of C_(4)F_(7)N/CO_(2)based GIT.

关键词： interface solid insulation