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High Voltage 2024年第1期9卷 2-21页

作者： Yanan Wang Linyuan Ren Zihao Yang Saikang Shen Zichen Deng Qi Yuan Weidong Ding Zhenjie Ding School of Electrical engineering Xi'an Jiaotong UniversityXi'anChina School of electronic and Information engineering Xi'an Jiaotong UniversityXi'anChina

Solid-state high voltage high repetitive pulse generators have a broad prospect in various *** high power and high-frequency operation of the pulse generator suffer from the massive heat dissipation problem,which limits the improvement of the output parameters and even affects the *** article focuses on heat management technology for high voltage high repetitive pulse ***,the typical circuit topology of the high repetitive pulse generators was *** the perspective of different application requirements,the demands of the heat management design were ***,the heat generation characteristics and difficulties of solid-state high voltage high repetitive pulse generators were ***,the different stateof-art cooling techniques were reviewed,and their applicability and limitations for the high voltage high repetitive generators were ***,a flow chart for heat management design was given.

关键词： pulse state high

Effect of the yaw angle on turbulent flow structures around the submarine model

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Journal of Hydrodynamics 2024年第3期36卷 421-434页

作者： Yi-jing Hu Yi Qu Qin Wu Biao Huang School of Mechanical engineering Beijing Institute of TechnologyBeijing100081China Beijing Institute of electronic System engineering Beijing100854China

The objective of this paper is to investigate the turbulent flow structures around the submarine model and evaluate the effect of the yaw angle on the turbulent flow *** large eddy simulation based on the boundary data immersion method is used to *** computational domain consists of 1.2×10^(8)uniformly distributed Cartesian orthogonal grid nodes to capture the basic flow characteristics around the *** pressure coefficient,friction coefficient and wake velocity distribution are in good agreement with the experimental *** different types of vortex structures were mainly captured around the model,including horseshoe vortex,sail tip vortex and crossflow separation *** the increase of the yaw angle,the asymmetry of the horseshoe vortex and the tip vortex gradually increases,and the vortex strength of the vortex leg on the windward of the horseshoe vortex and the vortex strength of the tip vortex also increase *** the crossflow separation vortex,the flow separation zone gradually expands and migrates downstream with the increase of the yaw angle.

关键词： Vortex structure submarine model boundary data immersion method yaw angle

A Deep Learning Based Broadcast Approach for Image Semantic Communication over Fading Channels

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China Communications 2024年第7期21卷 78-94页

作者： Ma Kangning Shi Yuxuan Shao Shuo Tao Meixia The department of electronic engineering Shanghai Jiao Tong UniversityShanghai 200240China The School of Cyber and engineering Shanghai Jiao Tong UniversityShanghai 200240China

We consider an image semantic communication system in a time-varying fading Gaussian MIMO channel,with a finite number of channel states.A deep learning-aided broadcast approach scheme is proposed to benefit the adaptive semantic transmission in terms of different channel *** combine the classic broadcast approach with the image transformer to implement this adaptive joint source and channel coding(JSCC)***,we utilize the neural network(NN)to jointly optimize the hierarchical image compression and superposition code mapping within this *** learned transformers and codebooks allow recovering of the image with an adaptive quality and low error rate at the receiver side,in each channel *** simulation results exhibit our proposed scheme can dynamically adapt the coding to the current channel state and outperform some existing intelligent schemes with the fixed coding block.

关键词： broadcast approach deep learning fading channels semantic communication

Probabilistic modeling of multifunction radars with autoregressive kernel mixture network

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Defence Technology（防务技术） 2024年第5期35卷 275-288页

作者： Hancong Feng Kaili.Jiang Zhixing Zhou Yuxin Zhao Kailun Tian Haixin Yan Bin Tang School of Information and Communication engineering University of Electronic Science and Technology of ChinaChengdu 611731China

The task of modeling and analyzing intercepted multifunction radars(MFRs)pulse trains is vital for cognitive electronic *** methodologies predominantly rely on prior information or heavily constrained models,posing challenges for non-cooperative *** paper introduces a novel approach to model MFRs using a Bayesian network,where the conditional probability density function is approximated by an autoregressive kernel mixture network(ARKMN).Utilizing the estimated probability density function,a dynamic programming algorithm is proposed for denoising and detecting change points in the intercepted MFRs pulse *** results affirm the proposed method's efficacy in modeling MFRs,outperforming the state-of-the-art in pulse train denoising and change point detection.

关键词： Probabilistic forecasting Multifunction radar Unsupervised learning Change point detection Outlier detection

Asymmetric two-dimensional diffraction grating via a vortex field in an inverted-Ytype atomic system

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Communications in Theoretical Physics 2024年第5期76卷 77-85页

作者： Duo Zhang Ke Wang Kunpeng Zhao Mei Wang Zhaoyu Sun School of Electrical and electronic engineering Wuhan Polytechnic UniversityWuhan 430023China

We propose a theoretical scheme to realize a two-dimensional(2D)diffraction grating in a four-level inverted-Y-type atomic system coupled by a standing-wave(SW)field and a Laguerre-Gaussian(LG)vortex *** to asymmetric spatial modulation of the LG vortex field,the incident probe field can be lopsidedly diffracted into four domains and an asymmetric 2D electromagnetically induced grating is *** adjusting the detunings of the probe field and the LG vortex field,the intensities of the LG vortex field and the coherent SW field,as well as the interaction length,the diffraction properties and efficiency,can be effectively *** addition,the effect of the azimuthal parameter on the Fraunhofer diffraction of the probe field is also *** asymmetric 2D diffraction grating scheme may provide a versatile platform for designing quantum devices that require asymmetric light transmission.

关键词： asymmetric diffraction grating standing-wave field Laguerre-Gaussian vortex field diffraction property

Convolutional neural network adaptation and optimization method in SIMT computing mode

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The Journal of China Universities of Posts and Telecommunications 2024年第2期31卷 105-112页

作者： Feng Zhenfu Zhang Yaying Yang Lele Xing Lidong School of electronic engineering Xi'an University of Posts and TelecommunicationsXi'an 710121China

For studying and optimizing the performance of general-purpose computing on graphics processing units(GPGPU)based on single instruction multiple threads(SIMT)processor about the neural network application,this work contributes a self-developed SIMT processor named Pomelo and correlated assembly *** parallel mechanism of SIMT computing mode and self-developed Pomelo processor is briefly introduced.A common convolutional neural network(CNN)is built to verify the compatibility and functionality of the Pomelo *** computing flow with task level and hardware level optimization is adopted on the Pomelo processor.A specific algorithm for organizing a Z-shaped memory structure is developed,which addresses reducing memory access in mass data computing *** the above-combined adaptation and optimization strategy,the experimental result demonstrates that reducing memory access in SIMT computing mode plays a crucial role in improving performance.A 6.52 times performance is achieved on the 4 processing elements case.

关键词： parallel computing single instruction multiple threads(SIMT) convolutional neural network(CNN) memory optimization

Decision Aid Model for Private-owned Electric Vehicles Participating in Frequency Regulation Ancillary Service Market

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Journal of Modern Power Systems and Clean Energy 2024年第2期12卷 621-629页

作者： Liwei Wang Yingyun Sun Haotian Wang Pengfei Zhao Muhammad Safwan Jaffar School of Electrical and electronic engineering North China Electric Power UniversityBeijing 102206China

To reduce the difficulty and enhance the enthusiasm of private-owned electric vehicles(EVs) in participating in frequency regulation ancillary service market(FRASM), a decision aid model(DAM) is proposed. This paper presents three options for EV participating in FRASM, i. e., the base mode(BM), unidirectional charging mode(UCM), and bidirectional charging/discharging mode(BCDM), based on a reasonable simplification of users' participating willingness. In BM, individual EVs will not be involved in FRASM, and DAM will assist users to set the optimal charging schemes based on travel plans under the time-of-use(TOU) price. UCM and BCDM are two modes in which EVs can take part in FRASM. DAM can assist EV users to create their quotation plan, which includes hourly upper and lower reserve capabilities and regulation market mileage prices. In UCM and BCDM, the difference is that only the charging rate can be adjusted in the UCM, and the EVs in BCDM can not only charge but also discharge if necessary. DAM can estimate the expected revenue of all three modes, and EV users can make the final decision based on their preferences. Simulation results indicate that all the three modes of DAM can reduce the cost, while BCDM can get the maximum expected revenue.

关键词： Electric vehicle(EV) frequency regulation decision aid model(DAM) utility maximization battery wear cost

Sintering of phosphor-glass composites goes ultrafast

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Science China Materials 2024年第8期67卷 2711-2712页

作者： Xiaoyong Huang College of electronic Information and Optical engineering Taiyuan University of TechnologyTaiyuan 030024China

Nowadays,with the rapid technological progress of high-quality lightings and high-end displays,high-power white light-emitting diodes(WLEDs)and high-brightness white laser diodes(WLDs)featuring with high energy density excitation,high output power and high device stability have been extensively investigated and regarded as the new-generation solid-state light sources[1–6].

关键词： diodes WLED white

Preparation and characteristic study of Schottky diodes based on Ga_(2)O_(3)thin films

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The Journal of China Universities of Posts and Telecommunications 2024年第2期31卷 28-37页

作者： Zhang Xuhui Chen Haifeng Liu Xiangtai Lu Qin Wang Zhan Cheng Hang Che Lujie Guan Youyou Han Xiaocong School of electronic engineering Xi'an University of Posts and TelecommunicationsXi'an 710121China

This study uses atomic layer deposition(ALD)to grow Ga_(2)O_(3)films on SiO_(2)substrates and investigates the influence of film thickness and annealing temperature on film *** diode devices are fabricated based on the grown Ga_(2)O_(3)films,and the effects of annealing temperature,electrode size,and electrode spacing on the electrical characteristics of the devices are *** results show that as the film thickness increases,the breakdown voltage of the fabricated devices also increases.A Schottky diode with a thickness of 240 nm can achieve a reverse breakdown voltage of 300 *** film quality significantly improves as the annealing temperature of the film *** a voltage of 5 V,the current of the film annealed at 900℃is 64 times that of the film annealed at 700℃.The optimum annealing temperature for Ohmic contact electrodes is 450℃.At 550℃,the Ohmic contact metal tends to burn,and the performance of the device is *** the electrode spacing increases the forward current of the device but decreases the reverse breakdown *** the Schottky contact electrode size increases the forward current,but the change is not significant,and there is no significant change in the reverse breakdown *** device also performs well at high temperatures,with a reverse breakdown voltage of 220 V at 125℃.

关键词： atomic layer deposition(ALD) Ga_(2)O_(3)film Schottky diode annealing temperature

Design of digital calibration based on variable step size of sub-binary SAR ADC

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The Journal of China Universities of Posts and Telecommunications 2024年第2期31卷 62-71页

作者： Liu Wei Zhao Yanke Shang Shiguang School of electronic engineering Xi'an University of Posts and TelecommunicationsXi'an 710121China

Addressing the impact of capacitor mismatch on the conversion accuracy of successive approximation register analog-to-digital converter(SAR ADC),a 12-bit 1 MS/s sub-binary SAR ADC designed using variable step size digital calibration was *** least mean square(LMS)calibration algorithm was employed with a ramp signal used as the calibration *** errors,extracted under injected disturbances,underwent iterative training to optimize weight *** address the trade-off between conversion accuracy and speed caused by a fixed step size,a novel variable step size algorithm tailored for SAR ADC calibration was *** core circuit and layout of the SAR ADC were implemented using the Taiwan Semiconductor Manufacturing Company(TSMC)0.35μm complementary metal-oxide-semiconductor(CMOS)commercial *** of the SAR ADC calibration algorithm was conducted using Simulink,demonstrating quick convergence and meeting conversion accuracy requirements compared to fixed step size *** results indicated that the convergence speed of the LMS digital calibration algorithm with variable step size was approximately eight times faster than that with a fixed step size,also yielding a lower mean square error(MSE).After calibration,the simulation results for the SAR ADC exhibited an effective number of bit(ENOB)of 11.79 bit and a signal-to-noise and distortion ratio(SNDR)of 72.72 dB,signifying a notable enhancement in the SAR ADC performance.

关键词： successive approximation register analog-to-digital converter(SAR ADC) variable step size digital calibration disturbance technique