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Chinese Journal of Aeronautics 2023年第10期36卷 459-470页

作者： Fei CHENG Guangming YANG Yunsen HU Bingyan YUAN Xiaozhi HU School of Materials Science and Engineering Southwest University of Science and TechnologyMianyang 621010China Engineering Research Center of Biomass Materials Ministry of EducationSouthwest University of Science and TechnologyMianyang 621010China Department of Mechanical Engineering University of Western AustraliaPerth WA6009Australia

Compressive strengths and elastic moduli of Carbon Fiber Reinforced Polymer(CFRP)composites can be noticeably improved by multiple ultra-thin interlays with non-woven Aramid Pulp(AP)micro/nano-fibers.10-ply CFRP specimens with 0,2,4,6,8 g/m^(2)AP were tested under uniaxial compression.Those flexible AP fibers,filling the resin-rich regions and further constructing the fiber bridging at the ply interfaces,can effectively suppress delamination growth and lead to very good improvements both in the compressive strength and the elastic modulus.The CFRP specimen with an optimum interlay thickness has a distinct shear failure mode instead of the typical delamination cracking along the direction of continuous carbon fibers.Compressive Strengths After Impacts(CAI)of 12.35 J were also measured,up to 90%improvement in CAI has been observed.It is concluded those ultra-thin interlays of non-woven AP micro/nano-fibers are beneficial to design and manufacture“high strength”CFRP composites.

关键词： Compressive strength Carbon Fiber Reinforced Polymer(CFRP) Aramid pulp interleaving Interfacial reinforcing

interleaving Radiosity

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Journal of Computer Science & Technology 2002年第1期17卷 1-8页

作者：吴恩华王文平等 FacultyofScienceandTechnology UniverityofMacaoMacaoP.R.China DepartmentofComputerScience UniversityofHongKongHongKongP.R.China

A system of linear equations is in general solved to approximate discretely the illumination function in radiosity computation. To improve the radiosity solution, a method that performs shooting and gathering in an interleaving manner is proposed in the paper.Besides, a criterion has been set up and tested for choosing object elements used in the gathering operation, and a criterion is established to quantify the solution errors by taking into account more reasonably of the human perception of the radiosity solution. Experimental results show that the method proposed has nice performance in improving the radiosity solution.

关键词： radiosity global illumination progressive refinement shooting and gathering interleaving

Anti-interference ultra-wideband system based on spreading and interleaving

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Journal of Systems Engineering and Electronics 2007年第2期18卷 236-242页

作者： Zhang Shibing Zhang Lijun Nantong Univ. Nantong 226007 P. RChina Nanjing Univ. of Posts and Telecommunications Nanjing 210003 P. It. China

To suppress the interference in the ultra-wideband （AI-UWB） system is a challenging problem. An anti-interference multiband orthogonal frequency-division multiplexing ultra-wideband （AI-UWB） system, based on spreading and interleaving is addressed. It will exploit the frequency diversity across the subcarriers and provide the robustness to narrow-band interference, by spreading the coded bit streams within each sub-band and interleaving across all sub-bands. Simulating results show that the spreading and interleaving provide about 5 dB to 10 dB advantages over the conventional multiband orthogonal frequency-division multiplexing ultra-wideband system in signal-to-interference ratio. Spreading and interleaving is an effective cure for enhancing the robustness to narrowband interference.

关键词： Communications technology Anti-interference Spreading interleaving Ultra-wideband.

A correlation-breaking interleaving of polar codes in concatenated systems

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Science China(Information Sciences) 2021年第10期64卷 270-271页

作者： Ya MENG Liping LI Chuan ZHANG Key Laboratory of Intelligent Computing and Signal Processing of the Ministry of Education of China Anhui University National Mobile Communications Research Laboratory Southeast University

Dear editor,Polar codes, along with a low complexity successive cancellation(SC) decoding, were discovered in [1] by Ar?kan. It is shown in [2] that the bit errors with the SC decoding are correlated. To improve the performance, other decoding techniques [3, 4] and concatenation schemes [5, 6] were studied. In this study, the theoretical aspects of the error correlation are investigated to improve the decoding performance of polar codes. This is the first attempt to utilize the error correlation to improve the performance of polar codes.

关键词： Polar codes SC decoding BP decoding interleaving code concatenation

New quaternary sequences of even length with optimal auto-correlation

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Science China(Information Sciences) 2018年第2期61卷 125-137页

作者： Wei SU Yang YANG Zhengchun ZHOU Xiaohu TANG School of Economics and Information Engineering Southwestern University of Finance and Economics Science and Technology on Communication Security Laboratory School of Mathematics Southwest Jiaotong University Provincial Key Lab of Information Coding and Transmission Institute of Mobile CommunicationsSouthwest Jiaotong University

Sequences with low auto-correlation property have been applied in code-division multiple access communication systems, radar and cryptography. Using the inverse Gray mapping, a quaternary sequence of even length N can be obtained from two binary sequences of the same length, which are called component sequences. In this paper, using interleaving method, we present several classes of component sequences from twin-prime sequences pairs or GMW sequences pairs given by Tang and Ding in 2010; or two, three or four binary sequences defined by cyclotomic classes of order 4. Hence we can obtain new classes of quaternary sequences, which are different from known ones, since known component sequences are constructed from a pair of binary sequences with optimal auto-correlation or Sidel’nikov sequences.

关键词： binary sequences quaternary sequences Gray mapping interleaving cyclotomy

A Holistic Approach to Enhance FRCS General Surgery Examination Training Using Adult Learning Model: A Non-Profit Initiative

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Surgical Science 2023年第8期14卷 565-574页

作者： Rahul Winayak Sanjay V. Joshi Goran Ahmed Anne O’Neill Ishy Gurung Muhammad Nadeem Muhammed Alwahid Sudeendra Doddi Manas Kumar Dube Ahmad Mirza Rishabha D. Sharma Bristol Medical School University of Bristol Bristol UK Medway Maritime Hospital Gillingham Kent UK Frimley Park Hospital Portsmouth Road Camberley UK University Hospitals Plymouth NHS Trust Plymouth UK Northern Devon Healthcare NHS Trust Barnstaple UK Yeovil District Hospital NHS Foundation Trust Yeovil UK Inverclyde Royal Hospital Greenock Scotland UK Princes Royal University Hospital Orpington UK Sherwood Forest Hospitals NHS Foundation Trust Mansfield UK Augusta University Medical Center Augusta GA USA

Objectives: To evaluate the impact of adult learning and simulation-based learning (SBL) on surgical trainees’ learning experiences and Fellowship of the Royal College of Surgeons (FRCS) Section 2 General Surgery examination pass rate. Methods: This was a cross-sequential study involving 148 surgical candidates (72 UK trainees, 75 non-UK trainees) who had attended our revision course (Phoenix FRCS Course) from June 2017 until 2023. Each course comprised a two-day weekend preparation with dedicated sections for clinical, viva, and academic reading, incorporating SBL as its key learning style. We maintained a prospective database of candidate and course details, examination results, and feedback since the course inception. Results: We found that 97% of candidates passed the FRCS examination after their first attempt. The course was attended once by 89% of candidates, and only 3 of the 148 candidates exhausted all four attempts at the examination. Candidate feedback for the course and its style of learning was positive, with simulation-based table viva sessions and virtual clinical sessions proving the most popular learning sessions (95% and 80% of candidates attending courses run in December 2017, April 2018, and May 2021 rated them “Excellent” respectively). Conclusions: The course is centered around shared adult learning and mindfulness tools to encourage candidates to learn from each other and develop confidence and mastery in all domains of surgical practice. These methods have been shown to be effective in achieving high success rates in the Intercollegiate and International FRCS examinations for UK and overseas surgeons.

关键词： Simulation-Based Learning (SBL) Adult Learning Mindfulness Tools FRCS Examination interleaving

A Packet-interleaving Scheme Using RS Code for Burst Errors in Wireless Sensor Networks

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Wireless Sensor Network 2015年第7期7卷 83-99页

作者： Tsang-Ling Sheu Yen-Hsi Kuo Zi-Tsan Chou Department of Electrical Engineering National Sun Yat-Sen University Kaohsiung Taiwan

In this paper, we propose a packet-interleaving scheme (PIS) for increasing packet reliability under burst errors in wireless sensor networks (WSN). In a WSN, packet errors could occur due to weak signal strength or interference. These erroneous packets have to be retransmitted, which will increase network load substantially. The proposed PIS, encoding data using Reed-Solomon (RS) codes, can classify data into two different types: high-reliability-required (HRR) data and non-HRR data. An HRR packet is encoded with a short RS symbol, while a non-HRR packet with a long RS symbol. When an HRR and a non-HRR packet arrive at a sensor, they are interleaved on a symbol-by-symbol basis. Thus, the effect of burst errors (BE) is dispersed and consequently the uncorrectable HRR packets can be reduced. For the purpose of evaluation, two models, the uniform bit-error model (UBEM) and the on-off bit-error model (OBEM), are built to analyze the packet uncorrectable probability. In the evaluation, we first change the lengths of BE, then we vary the shift positions in a BE period, and finally we increase the number of correctable symbols to observe the superiority of the proposed PIS in reducing packet uncorrectable probability.

关键词： WSN RS Code Burst Errors interleaving Packet Uncorrectable Probability

Research on Control Strategy of 2-phase interleaving Magnetic Integrated VRM

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Energy and Power Engineering 2013年第4期5卷 657-660页

作者： Rui Guo Cong Wang Yugang Yang 1School of Mechanical Electronic & Information Engineering China University of Mining & Technology Beijing China 2Faculty of Electrical and Control Engineering Liaoning Technical University Huludao Liaoning China Faculty of Electrical and Control Engineering Liaoning Technical University Huludao Liaoning China School of Mechanical Electronic & Information Engineering China University of Mining & Technology Beijing China

A kind of 2-phase interleaving coupled magnetic integrated VRM is studied and the corresponding passivity-based control strategy is put forward. The model of this kind of magnetic integrated VRM is constructed, and the performance of this 2-phase interleaving magnetic integrated VRM of passivity-based control is verified by simulation experiments. The results proved that this kind of passivity-based control strategy can decrease the steady state current ripple and the dynamic output voltage under load disturbance.

关键词： VRM Magnetic Integrated interleaving Coupled Inductors

Performance Evaluation of a Permanent Magnet Electric-Drive- Reconfigured Onboard Charger with Active Power Factor Correction

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CES Transactions on Electrical Machines and Systems 2019年第1期3卷 72-80页

作者： Feng Yu Zhihao Zhu Jingfeng Mao Juping Gu the School of Electrical Engineering Nantong UniversityNantong 226019China

This paper presents a comprehensive charging operation for an electric-drive-reconfigured onboard charger(EDROC)with active power factor correction(APFC).The charging topology exclusively utilizes the three-phase permanent magnet synchronous motor(PMSM)propulsion system as a three-channel boost-type converter in which only a contactor and a small diode bridge are added.First,the operation scenario of the EDROC is introduced.Second,the relationship between electromagnetic torque and rotor position is investigated.Third,the current ripple cancellation of the EDROC is discussed in detail.Moreover,to implement the single-phase APFC along with charging voltage/current regulation of propulsion battery,control strategies including current balancing and synchronous/interleaving PWM strategies are incorporated.Finally,200W proof-of-concept prototype-based tests are conducted under different operation scenarios.

关键词： Active power factor correction current balancing electric-drive-reconfigured electromagnetic torque interleaving onboard charger.

Uplink Multiple Access Schemes for 5G:A Survey

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ZTE Communications 2017年第B6期15卷 31-40页

作者： YANG Shan CHEN Peng LIANG Lin ZHU Jianchi SHE Xiaoming Technology Innovation Center China TelecomBeijing 102209China

In non-orthogonal multiple access(NMA) system, signal transmitter and receiver are jointly optimized, so that multiple layers ofdata from more than one user can be simultaneously delivered in the same resource. To meet the 5G requirements on the numberof connections and spectral efficiency, uplink NMA is becoming an important candidate technology and has been extensively stud-ied in 3GPP. A number of uplink NMA schemes from different industrial companies have been proposed in recent 3GPP meet-ings. In terms of their basic technique principles, this paper classifies these NMA schemes into three categories, namely: scram-bling based NMA schemes, interleaving based NMA schemes, and spreading based NMA schemes. Moreover, the key characteris-tics of these schemes are summarized, and the detailed introduction of each scheme is provided according to the comprehensivesurvey of the latest progress in 3GPP 5G standardization work.

关键词： 5G non-orthogonal multiple access scrambling interleaving spreading