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Journal of Communications and Information Networks 2024年第2期9卷 151-161页

作者： Hongyu Li Jun Gong Wenchi Cheng The 54th research Institute of China Electronics Technology group Corporation Shijiazhuang 050080China State Key Laboratory of Integrated Services Networks Xidian UniversityXi’an 710071China

Millimeter-wave (mmWave) is capable of achieving gigabit/second communication capacity and centimeter-level sensing accuracy and has become one of the main frequency bands for integrated sensing and communications (ISAC) research. Hybrid beamforming techniques have attracted much attention for solving the high path loss of mmWave and further reducing the hardware cost of the system. However, the related studies based on multicarrier and fully-connected hybrid architectures are still limited. For this reason,this paper investigates the orthogonal frequency division multiplexing (OFDM) based mmWave fully-connected hybrid architecture ISAC system to form a stable communication beam and dynamically varying sensing beam. In order to realize the aforementioned multifunctional beams, the hybrid beamformer design problem based on weighted error minimization of multicarrier is proposed and solved efficiently using the penalty dual decomposition (PDD) algorithm. Meanwhile, based on the echo model, the multicarrier multiple signal classification (MUSIC) algorithm for target angle of arrival estimation and the two-dimensional discrete Fourier transform(2D-DFT)algorithm for distance and velocity estimation are proposed, respectively. Numerical simulation results show that by adjusting the weighting factor,a flexible trade-off can be formed between the communication spectrum efficiency and the sensing accuracy error.

关键词： integrated sensing and communications hybrid beamforming fully-connected architecture millimeter-wave

Availability analysis of private cloud safety computer platform based on the Markov process

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Transportation Safety and Environment 2024年第1期6卷 103-108页

作者： Limin Fu Jiakun Wen Southwest Jiaotong University The School of Information Science&TechnologyChengduSichuan 610097China CRSC research&Design Institute group Co. LtdBeijing 100070China

To ensure the correctness of train control system design and development,the ways of simulation,test and formalization were *** to the safe critical attribute of train control system,the characters related to system safety were propounded such as real time,hybrid,distribution(concurrence)and reactivity,and the specific formal methods associated with every character were introduced in *** analysis and classification of the methods were done based on their mathematical basis and applications,and their advantages and disadvantages were *** result indicates that every method has determinate limitations,which is determined by the essences of model checking and theory *** is pointed out that the presentation of new method,the expansion of existing methods and the integration of many methods will be the development trend of formalization in train control system.

关键词： safety computer Markov process cloud computing availability analysis

Construction and Validity of Chinese Translation of the Universal Mental Health Literacy Scale for Adolescents

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International Journal of Mental Health Promotion 2024年第8期26卷 671-677页

作者： Qi Wang Qi Wang Yuxuan Ji Kexu Chen Kaiyun Li Fanlu Jia Ting Peng School of Education and Psychology University of JinanJinan250022China Psychology research group Jinan Quanjing Middle SchoolJinan250024China

Background:In this study,the Universal Mental Health Literacy Scale for Adolescents(UMHL-A)was revised and tested for its reliability and validity in Chinese middle school students,thus establishing a useful tool for assessing the mental health of individuals in this ***:Our sample comprised 1208 junior high school students(58.85%male),aged between 11 and 15 years *** Chinese version of the scale includes a mental health attitude subscale and mental health knowledge subscale,including attitudes towards seeking help,attitudes related to stigma,general mental health knowledge,and knowledge about specific mental illnesses,encapsulated in a total of 17 items.A series of psychometric analyses such as exploratory factor analysis(EFA),confirmatory factor analysis(CFA),and internal consistency reliability estimation were carried out in this ***:The results of the CFA indicated that the two-factor model had an acceptable model fit(Attitude(UMHL-A Likert):χ^(2)/df=4.107;RMSEA=0.072;SRMR=0.045;TLI=0.932;CFI=0.954;Knowledge(UMHL-A T/F):χ^(2)/df=3.647;RMSEA=0.066;SRMR=0.044;TLI=0.923;CFI=0.945).The Cronbach’s alpha coefficient of subscales of the Chinese version UMHL-A were 0.80 and 0.78,***:In general,the Chinese version of the Universal Mental Health Literacy Scale for adolescents has good reliability and validity and can be used as a tool to measure the mental health literacy of Chinese adolescents.

关键词： Mental health literacy Chinese adolescents validity

Cardiovascular risk burden and disability:findings from the International Mobility in Aging Study(IMIAS)

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Journal of Geriatric Cardiology 2024年第3期21卷 331-339页

作者： Juan-David Martinez-Aristizábal Carmen-Lucia Curcio Juliana Fernandes Afshin Vafael Cristiano dos Santos Gomes Fernando Gomez Internal Medicine Critical Care DepartmentPablo Tobón Uribe HospitalMedellínColombia research group in Geriatrics and Gerontology Faculty of Health SciencesUniversidad de CaldasManizalesColombia Laboratory of Physical Therapy and Collective Health Physical Therapy DepartmentFederal University of PernambucoJornalista Aníbal Fernandes Avenue RecifeBrazil Department of Public Health Sciences Queen’s UniversityKingstonONCanada Department of Physiotherapy University of PernambucoBR 203KmBrazil

BACKGROUND The association of cardiovascular risk burden with disability is *** examined the association between trajectories of the Framingham general cardiovascular disease risk score(FGCRS)with the trajectories of limitations of physical function in older *** A total of 1219 participants with no disabilities from the International Mobility in Aging Study(IMIAS)study who had up to three repeated measures of FGCRS between 2012–2016 and without a history of stroke or coronary heart disease at baseline and follow-up were *** at baseline was assessed and categorized into *** function was evaluated with the Short Physical Performance Battery(SPPB).The data were analyzed using linear mixed-effects *** At baseline,FGCRS ranged between 3–94(mean score:24±15.8),participants were 32(2.6%),502(41.2%)and 685(56.2%)in lowest,middle,and highest tertiles,*** the trajectories of limitations of physical function,the lowest FGCRS had no differences,while the middle and highest had a decrease in physical performance between 2012–2014(P=0.0001).Age,being female,living in Andes Mountains,having middle and highest FGCRS,higher alcohol consumption,being obese,lack of exercise and cognitive impairment increase the probability of disability(P<0.05).Alternatively,living in more developed regions and having a higher educational level reduced the probability of disability during the follow-up time(P<0.05).CONCLUSIONS Higher cardiovascular risk burden is associated with decreased physical performance,especially in *** suggest SPPB may provide a measure of cardiovascular health in older adults.

关键词： finding Battery burden

Digital Twin Modeling and Simulation Optimization of Transmission Front and Middle Case Assembly Line

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 3233-3253页

作者： Xianfeng Cao Meihua Yao Yahui Zhang Xiaofeng Hu Chuanxun Wu Process research Institution China National Heavy Duty Truck Group Co.Ltd.Jinan250100China Transmission Factory China National Heavy Duty Truck Group Co.Ltd.Jinan250100China G Intelligent Manufacturing research Center Institute of Marine EquipmentShanghai Jiao Tong UniversityShanghai200240China Institute of Intelligent Manufacturing and Information Engineering School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai200240China

As the take-off of China’s macro economy,as well as the rapid development of infrastructure construction,real estate industry,and highway logistics transportation industry,the demand for heavy vehicles is increasing rapidly,the competition is becoming increasingly fierce,and the digital transformation of the production line is *** one of themost important components of heavy vehicles,the transmission front andmiddle case assembly lines have a high degree of automation,which can be used as a pilot for the digital transformation of *** ensure the visualization of digital twins(DT),consistent control logic,and real-time data interaction,this paper proposes an experimental digital twin modeling method for the transmission front and middle case assembly ***,theDT-based systemarchitecture is designed,and theDT model is created by constructing the visualization model,logic model,and data model of the assembly ***,a simulation experiment is carried out in a virtual space to analyze the existing problems in the current assembly ***,some improvement strategies are proposed and the effectiveness is verified by a new simulation experiment.

关键词： Transmission front and middle case assembly line digital twin(DT) simulating optimization intelligent manufacturing

Study of interfacial transition zones between magnesium phosphate cement and Portland cement concrete pavement

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第3期11卷 523-537页

作者： Fei Liu Baofeng Pan Changjun Zhou Ge Li Xiaocun Wang Jiaquan Li Faculty of Infrastructure Engineering Dalian University of TechnologyDalian 116024China Tongren City Transportation Bureau Tongren 554300China Beijing Civil Aviation Design and research Institute of China Design group Beijing 101318China

The Portland cement concrete pavement(PCCP)often suffers from different environmental distresses and vehicle load failure,resulting in slab corner fractures,potholes,and other *** repair has become one of the effective ways to open traffic *** this study,a novel type of rapid repair material,basalt fiber reinforced polymer modified magnesium phosphate cement(BFPMPC),is used to rapidly repair ***,the mechanical properties and characteristics of the repair interfaces which are named interfacial transition zones(ITZs)formed by BFPMPC and cement concrete are focused on as a decisive factor for the performance of the rapid *** changing trend of the elastic moduli was studied by nanoindentation experiments in the ITZs with the deconvolution analysis that the elastic moduli of certain kinds of substances can be *** experimental results show that the elastic modulus of ITZ-1 with a width of about20μm can be regarded as 0.098 times of the aggregate,and 0.51 times of the ordinary Portland cement(OPC)*** BFPMPC-OPC mortar ITZ has roughly the same mechanical properties as the ITZ between aggregate and BFPMPC.A multi-scale representative two-dimensional model was established by random aggregate and a two-dimensional extended finite element method(XFEM)to study the mechanical properties of the repair *** simulation results show that the ITZ formed by the interface of BFPMPC and OPC mortar and basalt aggregate is the most vulnerable to failure,which is consistent with the nano-indentation experimental results.

关键词： Portland cement concrete pavement Interfacial transition zone Magnesium phosphate cement Repair interface Nanoindentation Mechanical properties and characteristics

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

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

Rice Variety Classification Based on Optimized Near-Infrared Spectral Classification Model

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Rice science 2024年第1期31卷 6-9,I0009-I0012页

作者： YANG Sen WANG Zhenmin ZHANG Houqing SONG Wenlong College of Computer and Control Engineering Northeast Forestry UniversityHarbin 150040China The 49th research Institute of China Electronics Technology group Corporation Harbin 150000China

Accurate classification of rice variety is essential to ensure the brand value of high-quality rice *** the impact of sample state on modeling optimization algorithms,rice samples after grinding and sealing were *** enhance the accuracy of rice variety classification,we introduced a spectral characteristic wavelength selection method based on adaptive sliding window permutation entropy(ASW-PE).

关键词： sealing Infrared grinding

Ultra reliability and massive connectivity provision in integrated internet of military things(IoMT)based on tactical datalink

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Defence Technology（防务技术） 2024年第3期33卷 386-398页

作者： Li Bing Yating Gu Lanke Hu Li Bowen Yang Lihua Jue Wang Yue Yin Northwestern Polytechnical University Xi'an 710072China China Academy of Information and Communications Technology Beijing 100191China China Intelligent and Connected Vehicles(Beijing)research Institute Co. LtdBeijing 100176China The 20th research Institute of China Electronic Technology group Corporation Xi’an 710068China Xidian University Xi'an 710071China

One of the major challenges arising in internet of military things(IoMT)is accommodating massive connectivity while providing guaranteed quality of service(QoS)in terms of ultra-high *** this regard,this paper presents a class of code-domain nonorthogonal multiple accesses(NOMAs)for uplink ultra reliable networking of massive IoMT based on tactical datalink such as Link-16 and joint tactical information distribution system(JTIDS).In the considered scenario,a satellite equipped with Nr antennas servers K devices including vehicles,drones,ships,sensors,handset radios,*** coded modulation,a special form of multiple input multiple output(MIMO)-NOMA is *** discussion starts with evaluating the output signal to interference-plus-noise(SINR)of receiver filter,leading to the unveiling of a closed-form expression for overloading systems as the number of users is significantly larger than the number of devices admitted such that massive connectivity is *** expression allows for the development of simple yet successful interference suppression based on power allocation and phase shaping techniques that maximizes the sum rate since it is equivalent to fixed-point programming as can be *** proposed design is exemplified by nonlinear modulation schemes such as minimum shift keying(MSK)and Gaussian MSK(GMSK),two pivotal modulation formats in IoMT standards such as Link-16 and *** results show that near capacity performance is ***,the performance is obtained using simple forward error corrections(FECs)of higher coding rate than existing schemes do,while the transmit power is reduced by 6 *** proposed design finds wide applications not only in IoMT but also in deep space communications,where ultra reliability and massive connectivity is a keen concern.

关键词： Satellite network Deep space communications Internet of military things Non-orthogonal multiple access MIMO Link-16 JITDS