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Chinese Journal of electronics 2024年第3期33卷 814-822页

作者： Junqi LIU Tao WEN Guo XIE Yuan CAO Clive Roberts Shaanxi Key laboratory of Complex System Control and Intelligent Information processing Xi'an University of Technology The School of Electronic and Information Engineering Beijing Jiaotong University Birmingham Centre for Railway Research and Education University of Birmingham

The fault diagnosis of railway point machines(RPMs) has attracted the attention of engineers and *** have studies considered diverse noises along the *** fulfill this aspect,a multi-time-scale variational mode decomposition(MTSVMD) is proposed in this paper to realize the accurate and robust fault diagnosis of RPMs under multiple *** decomposes condition monitoring signals after coarse-grained processing in varying *** this manner,the information contained in the signal components at multiple time scales can construct a more abundant feature space than at a single *** the experimental validation,a random position,random type,random number,and random length(4R) noise-adding algorithm helps to verify the robustness of the *** adequate experimental results demoristrate the superiority of the proposed MTSVMD-based fault diagnosis.

关键词： Fault diagnosis Condition monitoring Noise signal processing algorithms Aerospace electronics Rail transportation Robustness

Reconfigurable paper-based metamaterial antenna: Structural transition from 2D to 3D

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Science China(Technological Sciences) 2024年第9期67卷 2811-2816页

作者： PANG YaChen GAO Song YAO HuiMing WANG LiWei CAO JinQing ZHANG ZiDong XU JianChun GUO YunSheng BI Ke State Key laboratory of Information Photonics and Optical Communications School of ScienceBeijing University of Posts and TelecommunicationsBeijing 100876China Key laboratory for Liquid-Solid Structural Evolution and processing of Materials(Ministry of Education) Shandong UniversityJinan 250061China School of Electronic Information Engineering Inner Mongolia UniversityHohhot 010021China

Paper-based electronics offer a simple and cost-effective means to fabricate reconfigurable devices. In response to the problem of fixed shape and single function of most antennas, which limits their applications, a reconfigurable paper-based metamaterial antenna with 2D and 3D forms is presented for tunable operating frequency. The proposed antenna consists of two square split resonant rings fed by a coplanar waveguide. The working frequency of the 2D antenna is adjusted by the length, width, and opening size of the internal open resonant ring. While the folding angle of the antenna turns from 0° to 90°, the operating frequency of the paper-based metamaterial antenna changes from 2.759 to 4.223 GHz. In terms of 3D form, an additional resonant peak is generated by bending the paper-based metamaterial antenna, thus further realizing dual-band antenna *** a simple process flow, a series of proposed antennas are fabricated and evaluated. The simulated and measured results both demonstrate that the proposed antenna has a good performance in turning the working band. The environment-friendly nature and pliability of paper, as well as simple fabrication procedures, make paper-based metamaterial promising candidates for future green electronics.

关键词： paper-based reconfigurable antennas metamaterial

Detection method of forward-scatter signal based on Rényi entropy

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Journal of Systems Engineering and electronics 2024年第4期35卷 865-873页

作者： ZHENG Yuqing AI Xiaofeng YANG Yong ZHAO Feng XIAO Shunping State Key laboratory of Complex Electromagnetic Environment Effects on electronics and Information System National University of Defense TechnologyChangsha 410073China

The application scope of the forward scatter radar(FSR)based on the Global Navigation Satellite System(GNSS)can be expanded by improving the detection ***,the forward-scatter signal model when the target crosses the baseline is ***,the detection method of the for-ward-scatter signal based on the Rényi entropy of time-fre-quency distribution is proposed and the detection performance with different time-frequency distributions is ***-tion results show that the method based on the smooth pseudo Wigner-Ville distribution(SPWVD)can achieve the best ***,combined with the geometry of FSR,the influence on detection performance of the relative distance between the target and the baseline is ***,the proposed method is validated by the anechoic chamber measurements and the results show that the detection ability has a 10 dB improvement compared with the common constant false alarm rate(CFAR)detection.

关键词： forward scatter radar(FSR) Global Navigation Satellite System(GNSS) time-frequency distribution Rényi entropy signal detection

Ganoderma Lucidum Spore Oil enhances the effect of cyclophosphamide via inhibiting programmed death-1 and prolongs the survival of H22 tumor-bearing mice

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Journal of Traditional Chinese Medicine 2024年第4期44卷 652-659页

作者： JIANG Zhaojian CAI Hongfei YUAN Cheng CAO Lin XU Wendong HAN Yaming ZHANG Qin LI Jing WANG Qin LIU Juyan Guangzhou HanFang Pharmaceutical Company Limited National Engineering Research Center of Pharmaceutical Processing Technology of Traditional Chinese Medicine and Drug InnovationGuangdong Provincial Key Laboratory of Medicinal LipidsGuangzhou 510240China Zhongshan Medical College Sun Yat-sen UniversityGuangzhou 510080China Guangzhou Pharmaceutical Holdings Limited Guangzhou 510130China National Engineering Research Center of Pharmaceutical processing Technology of Traditional Chinese Medicine and Drug Innovation Guangzhou 510240China

OBJECTIVE:To investigate the effect of Ganoderma Lucidum Spore Oil(GLSO)on the tumor growth and survival of H22 tumor-bearing mice treated with cyclophosphamide(CTX),and explore the underlying ***:Allograft H22 hepatocellular carcinoma mouse model was applied to investigate the effect of GLSO on the tumor growth and survival of animals,and Kaplan-Meier survival analysis was used to analyze the life *** biochemical examination was used to determine the levels of alanine aminotransferase(ALT),aspartate aminotransferase(AST),urea(UREA)and creatinine(CRE).Western blot analysis was performed to detect Programmed Death-1(PD-1),Programmed Death Ligand 1(PD-L1),Janus Kinase 2(JAK2),phosphorylated signal Transducer and Activator of Transcription 3(p-STAT3),and signal Transducer and Activator of Transcription 3(STAT3)***:GLSO increased the anti-tumor effect of CTX and prolonged the survival of H22 tumor-bearing mice treated with ***,GLSO increased the thymus index and showed no obvious toxicity to liver functions of *** also decreased the level of UREA in H22 tumor-bearing mice treated with ***,GLSO could inhibit the expression of PD-1 in spleen,which was independent of JAK2 expression and STAT3 ***,GLSO did not affect the expression of PD-L1,JAK2,and p-STAT3 in tumor ***:GLSO could strengthen the anti-tumor effect of CTX and prolong the life span of H22 tumorbearing mice,while the underlying mechanism might be relevant to the amelioration effect of thymus function and inhibition of PD-1 expression in ***,these findings implied the promising role of GLSO in combination with CTX to extend the survival of patients in clinical chemotherapy of hepatocellular carcinoma.

关键词： carcinoma,hepatocellular cyclophosphamide survival programmed cell death 1 receptor Ganoderma Lucidum SporeOil

Distributed user pairing and effective computation offloading in aerial edge networks

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Chinese Journal of Aeronautics 2024年第4期37卷 378-390页

作者： Wei LIANG Shuhui WEN Lixin LI Jingjing CUI School of electronics and Information Northwestern Polytechnical UniversityXi’an CN710072China The State Key laboratory of Integrated Services Networks Xidian UniversityXi’an CN710126China School of electronics and Computer Science University of SouthamptonSouthampton SO167NSUK

Future Sixth-Generation (6G) mobile communication networks extremely require the global connectivity and the ground Base Stations (BSs) are difficult to develop in some specific areas,such as mountainous ***,the aerial networks are the key framework for the future communications,in which the aerial vehicle could act as the access ***,Mobile Edge Computing (MEC) is also essential to enhance the data processing capabilities of aerial *** this paper,we study a comprehensive communication-computation resource management problem for jointly optimizing user pairing,power and time allocation in the MEC aided Cognitive Radio (CR) aerial networks,namely CR-MEC aerial ***,this multilevel optimization problem could be decomposed into the user pairing and power allocation as well as time allocation *** the conceived CR-MEC aerial networks,we propose a User Pairing and Computation Offloading Management Algorithm (UPCOMA) based on three-sided matching theory,aiming to minimize the system’s energy *** the first step of UPCOMA,multiple Primary Users (PUs) and Cognitive Users (CUs) on the ground negotiate to each other with the suitable power allocation coefficients and construct the stable user ***,the stable user pairs would match to a high altitude platform who act as the base station,which is for appropriately allocating Transmission Time Slots (TSs) at the second step of ***,a hybrid offloading mode is proposed in our conceived networks in order to support ground users to offload their tasks adaptively according to their individual ***,the simulation results reveal that the relative performance of UPCOMA is close to that of the Brute-Force Search Algorithm (BFSA) with low ***,the hybrid offloading mode with less energy consumption supports much more ground user pairs to offload tasks compared to the binary mode.

关键词： Aerial edge computing Binary offloading Cognitive radio Hybrid offloading Resource management

Understanding the Thermal Impedance of Silicone Rubber/Hexagonal Boron Nitride Composites as Thermal Interface Materials

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Chinese Journal of Polymer Science 2024年第3期42卷 352-363,I0008页

作者： Yuan Ji Shi-Da Han Hong Wu Shao-Yun Guo Feng-Shun Zhang Jian-Hui Qiu The State Key laboratory of Polymer Materials Engineering Sichuan Provincial Engineering Laboratory of Plastic/Rubber Complex Processing TechnologyPolymer Research InstituteSichuan UniversityChengdu 610065China Institute of Chemical Materials China Academy of Engineering PhysicsMianyang 621900China Department of Mechanical Engineering Faculty of Systems Science and TechnologyAkita Prefectural UniversityAkita 015-0055Japan

Silicone rubber(SR) composites are most widely used as thermal interface materials(TIMs) for electronics heat dissipation. Thermal impedance as the main bottleneck limiting the performance of TIMs is usually neglected. Herein, the thermal impedance of SR composites loaded with different levels of hexagonal boron nitride(h-BN) as TIMs was elaborated for the first time by the ASTM D 5470 standard test and finite element analysis. It was found that elastic modulus and surface roughness of SR composites increased with the increase of h-BN content, indicating that the conformity was reduced. When the assembly pressure was 0.69 MPa, there existed an optimal h-BN content at which the contact resistance was minimum(0.39 K·cm^(2)·W^(-1)). Although the decreased bond line thickness(BLT) by increasing the assembly pressure was beneficial to reduce the thermal impedance, the proper assembly pressure should be selected to prevent the warpage of the contact surfaces and the increase in contact resistance, according to the compression properties of the SR composites. This study provides valuable insights into fabrication of high-performance TIMs for modern electronic device applications.

关键词： Thermal interface materials Hexagonal boron nitride Thermal impedance Surfaces

Highly efficient solution-processed organic photovoltaics enabled by improving packing behavior of organic semiconductors

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Science China Chemistry 2024年第3期67卷 890-897页

作者： Xinyue Cui Hongxiang Li Hao Lu Yuqiang Liu Guangliu Ran Rui Liu Huarui Zhang Xueqing Ma Dawei Li Yi Lin Jifa Yu Wenkai Zhang Lei Cai Yahui Liu Pei Cheng Andong Zhang Zaifei Ma Guanghao Lu Zhishan Bo College of Textiles and Clothing State Key Laboratory of Bio-fibers and Eco-textilesQingdao UniversityQingdao 266071China State Key laboratory of Polymer Materials Engineering College of Polymer Science and EngineeringSichuan UniversityChengdu 610065China Department of Physics and Applied Optics Beijing Area Major laboratory Center for Advanced Quantum StudiesBeijing Normal UniversityBeijing 100875China Shandong Province Key laboratory of Medical Physics and Image processing Technology School of Physics and ElectronicsShandong Normal UniversityJinan 250014China Beijing Key laboratory of Energy Conversion and Storage Materials College of ChemistryBeijing Normal UniversityBeijing 100875China Center for Advanced Low-Dimension Materials State Key Laboratory for Modification of Chemical Fibers and Polymer MaterialsCollege of Materials Science and EngineeringDonghua UniversityShanghai 201620China Frontier Institute of Science and Technology Xi'an Jiaotong UniversityXi'an 710054China

Solution processability is a unique property of organic semiconductors. The compact and regular π-π stacking between molecules is paramount in the performance of organic optoelectronic devices. However, it is still a challenge to improve their stacking quality without sacrificing the solution-processability from the aspect of materials design. Here, delicately engineered additives are presented to promote the formation of ordered aggregation of conjugated molecules by regulating their nucleation and growth dynamics. Intriguingly, the long-chain BTP-eC9-4F molecules can realize ordered aggregation comparable to short-chain ones without sacrificing processability. The domain size of BTP-eC9-4F aggregation is enlarged from 24.2 to 32.2 nm in blend *** exciton diffusion and charge transport become faster, contributing to the suppression of recombination losses. As a result, a power conversion efficiency of 19.2% is achieved in D18:BTP-eC9-4F based organic photovoltaics. Our findings demonstrate a facile strategy to improve the packing quality of solution-processed organic semiconductors for high-efficiency photovoltaics and beyond photovoltaics.

关键词： organic semiconductor organic photovoltaic charge transport solution processability

Gel electrolyte based high-performance fiber battery

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Science Bulletin 2024年第18期69卷 2811-2813页

作者： Linli Gan Mengdie Lei Guangming Cai Weilin Xu State Key laboratory of New Textile Materials and Advanced processing Technologies Wuhan Textile UniversityWuhan 430200China

Batteries have experienced rapid development due to their outstanding energy storage performance and widespread *** progress has driven advancements in electric vehicles,energy storage systems,and portable electronic devices,while also increasing demand for lightweight designs,high energy density,and environmental sustainability[1].However,traditional rigid batteries face significant challenges related to mechanical flexibility,safety,and environmental impact,making them unsuitable for the unique requirements of these emerging applications[2].Consequently,flexible fiber batteries have emerged,leveraging innovations in materials and structural design to offer energy solutions capable of bending,stretching,and adapting to various complex *** batteries hold great potential in applications such as wearable devices[3],flexible electronics[4],smart textiles[5,6],and biomedical devices[7].Traditional lithium-ion batteries are widely used due to their high energy density and long cycle life.

关键词： battery performance fiber

Simulations of superconducting quantum gates by digital flux tuner for qubits

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Chinese Physics B 2024年第7期33卷 210-222页

作者：耿霄何楷泳刘建设陈炜 laboratory of Superconducting Quantum Information processing School of Integrated CircuitsTsinghua UniversityBeijing 100084China Beijing Innovation Center for Future Chips Tsinghua UniversityBeijing 100084China Beijing National Research Center for Information Science and Technology Beijing 100084China26

The interconnection bottleneck caused by limitations of cable number, inner space and cooling power of dilution refrigerators has been an outstanding challenge for building scalable superconducting quantum computers with the increasing number of qubits in quantum processors. To surmount such an obstacle, it is desirable to integrate qubits with quantum–classical interface(QCI) circuits based on rapid single flux quantum(RSFQ) circuits. In this work, a digital flux tuner for qubits(DFTQ) is proposed for manipulating flux of qubits as a crucial part of the interface circuit. A schematic diagram of the DFTQ is presented, consisting of a coarse tuning unit and a fine-tuning unit for providing magnetic flux with different precision to qubits. The method of using DFTQ to provide flux for gate operations is discussed from the optimization of circuit design and input signal. To verify the effectiveness of the method, simulations of a single DFTQ and quantum gates including a Z gate and an iSWAP gate with DFTQs are performed for flux-tunable transmons. The quantum process tomography corresponding to the two gates is also carried out to analyze the sources of gate error. The results of tomography show that the gate fidelities independent of the initial states of the Z gate and the iSWAP gate are 99.935% and 99.676%,respectively. With DFTQs inside, the QCI would be a powerful tool for building large-scale quantum computers.

关键词： quantum computation superconducting electronics quantum control

Micro-flow structure at regime transition from bubbling to turbulent fluidization in a fluidized bed

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Particuology 2024年第6期89卷 117-130页

作者： Chaoyu Yan Yue Yuan Xiaoyang Wei Jesse Zhu State Key laboratory of Heavy Oil processing Beijing Key Laboratory of Process Fluid Filtration and SeparationCollege of Mechanical and Transportation EngineeringChina University of PetroleumBeijing 102249China China Beacons Institute The University of NottinghamNingbo315100China Department of Chemical and Biochemical Engineering University of Western OntarioLondonOntarioN6A 5B9Canada

Gas-solid fluidized beds have found extensive utilization in frontline manufacturing,in particular as low-velocity *** fluidization status,the bubbling or turbulent flow regime and the transition in between,determine the system performance in practical *** the convoluted hydrodynamics are quantitively evaluated through numerous data-processing methodologies,none of them alone can reflect all the critical information to identify the transition from the bubbling to the turbulent ***,this study was to exploit a coupling data processing methodology,in the combination of standard deviation,power spectrum density,probability density function,wavelet transform,and wavelet multiresolution method,to jointly explain the micro-flow structure at the regime transition from bubbling to turbulent *** transient differential pressure fluctuation was measured for the evaluation in a fluidized bed(0.267 m i.d.×2.5 m height)with FCC catalysts(d_(p)=65μm,ρ_(p)=1780kg/m^(3))at different superficial gas velocities(0.02–1.4 m/s).The results show that the onset of turbulent fluidization starts earlier in the top section of the bed than in the bottom *** wavelet decomposition displays that the fluctuation of differential pressure mainly concentrates on the sub-signals with an intermediate frequency *** sub-signals could be synthesized into three types of scales(micro-scale,meso-scale,and macro-scale),representing the multi-scale hydrodynamics in the fluidized *** micro-scale signal has the characteristic information of bubbling fluidization,and the characteristic information of turbulent fluidization is mainly represented by the meso-scale *** work provides a systematic comprehension of fluidization status assessment and serves as an impetus for more coupling analysis in this sector.

关键词： Flow regime transition Bubbling fluidization Turbulent fluidization Micro-flow structure Differential pressure fluctuation