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Inversely engineered metasurfaces for independent manipulation of transmitted and reflected light fields

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Science China(Physics,Mechanics & Astronomy) 2024年第7期67卷 97-106页

作者： Yongjian Liu Yu Luo Fei Zhang Mingbo Pu Hanlin Bao Mingfeng Xu Yinghui Guo Lanting Li Xiong Li Xiaoliang Ma Xiangang Luo National Key Laboratory of Optical Field Manipulation Science and Technology Chinese Academy of SciencesChengdu 610209China State Key Laboratory of Optical Technologies on Nano-Fabrication and Micro-Engineering Institute of Optics and ElectronicsChinese Academy of SciencesChengdu 610209China College of Materials Science and Opto-Electronic Technology University of Chinese Academy of SciencesBeijing 100049China Research Center on Vector Optical Fields Institute of Optics and ElectronicsChinese Academy of SciencesChengdu 610209China Tianfu Xinglong Lake Laboratory Chengdu 610299China

Independent manipulation of transmitted and reflected light fields is a key technology for the realization of multifunctional optical applications,which can be implemented based on multilayered plasmonic or supercell subwavelength ***,the former is not suitable for the optical bands,while the latter is insufficient in generating large phase ***,an adjoint-optimization-based inverse design methodology is proposed,which utilizes the polarization-selective local interference between individual meta-atoms and enables monolayer dielectric metasurfaces to decouple the wavefront of transmitted and reflected optical ***,this methodology serves to mitigate the aperiodic electromagnetic crosstalk inherent between adjacent meta-atoms,consequently leading to a significant enhancement in the performance of *** analyzed the physical mechanism of adjoint optimization and proposed the concept of phase factors,highlighting their importance in the rapid inverse design of meta-devices—an aspect often overlooked in previous *** demonstrate the feasibility and robustness of our method,we optimize monolayer metasurfaces with different initial *** devices efficiently focus and deflect x-linearly and y-linearly polarized incident light in transmission and reflection spaces,***,this methodology holds immense potential for designing multifunctional,high-performing metasurfaces that meet multiple constraints,opening up broad prospects for applications.

关键词： full-space metasurfaces adjoint optimization inverse design

Current optimization-based control of dual three-phase PMSM for low-frequency temperature swing reduction

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Defence Technology（防务技术） 2024年第4期34卷 238-246页

作者： Linlin Lu Xueqing Wang Luhan Jin Qiong Liu Yun Zhang Yao Mao Key Laboratory of Optical Engineering Chinese Academy of SciencesChengdu 610209China institute of Optics and electronics Chinese Academy of SciencesChengdu 610209China University of Chinese academy of sciences Beijing 100049China College of Electrical Engineering Sichuan UniversityChengdu 610065China

In this paper,a control scheme based on current optimization is proposed for dual three-phase permanent-magnet synchronous motor(DTP-PMSM)drive to reduce the low-frequency temperature *** reduction of temperature swing can be equivalent to reducing maximum instantaneous phase copper loss in this ***,a two-level optimization aiming at minimizing maximum instantaneous phase copper loss at each electrical angle is ***,the optimization is transformed to a singlelevel optimization by introducing the auxiliary variable for easy *** that singleobjective optimization trades a great total copper loss for a small reduction of maximum phase copper loss,the optimization considering both instantaneous total copper loss and maximum phase copper loss is proposed,which has the same performance of temperature swing reduction but with lower total *** this way,the proposed control scheme can reduce maximum junction temperature by 11%.Both simulation and experimental results are presented to prove the effectiveness and superiority of the proposed control scheme for low-frequency temperature swing reduction.

关键词： Dual three-phase PMSM Low-frequency temperature swing Copper loss Current optimization Connected neutral points

A muon high-resolution pseudorange measurement method: Application to muon navigation in confined spaces

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Chinese Journal of Aeronautics 2024年第4期37卷 391-404页

作者： Haoyang LI Chunxi ZHANG Xingming FAN Longjie TIAN Tianqi LI Yang PANG Yanqiang YANG institute of Optics and electronics School of Instrumentation Science and Optoelectronics EngineeringBeihang UniversityBeijing 100191China institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China

Confined spaces such as polar regions, deep earth and deep ocean are crucial navigation scenarios where traditional navigation techniques have difficulty in obtaining external signals for positioning. The cosmic ray muons, which carry the spatial and energetic information, are easy to penetrate these confined spaces. Therefore, the unique muon characteristic provides a new perspective to estimate detector position, which can be considered using in confined spaces *** this paper, a well-developed theory of muon navigation is established by combining a muon pseudorange measurement method. Moreover, an Equivalent Velocity Calculation Model(EVCM)and a Muon Sequence Matching Technology(MSMT) are proposed. The first model corrects flight pseudorange error caused by the relativistic energy loss and the second technology compensates the random error in pseudorange measurement. Further, a series of simulations are performed to analyze the muon events number which can be received by detector in different scenarios with the variations of zenith angle, detector area, varied detector plates gap, and muon flight ***, the simulation results demonstrate that the muon navigation update rate every 10 minutes can reach 5.989 in confined spaces at 100 m, and further pseudorange error analysis indicates that the meter-level positioning accuracy can be acquired. Finally, we construct a muon coincidence measurement scheme and verify that the laws of the muon positioning system for high-energy muons are consistent with the simulation results.

关键词： Muon navigation Cosmic ray muons Muon detection technology Muon transmission technology Pseudorange measurement

Multifunction-oriented high-mobility polymer semiconductors

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National Science Review 2024年第3期11卷 16-19页

作者： Mingliang Zhu Yunlong Guo Yunqi Liu Beijing National Laboratory for Molecular sciences Organic Solids Laboratory Institute of Chemistry Chinese Academy of Sciences School of Chemical sciences University of Chinese Academy of Sciences

The discovery of conductive polyacetylene has initiated interdisciplinary research into condensed matter physics and synthetic chemistry in organic electronics. Unlike their inorganic and small-molecule counterparts, polymer semiconductors possess the inherent advantages of facile solution processing,large-area manufacturing, excellent mechanical strength and intrinsic flexibility.

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Atomic tracking of thermally-driven structural evolution in 2D crystals:Case of NbSe_(2)

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InfoMat 2024年第2期6卷 90-98页

作者： Baofei Hou Teng Zhang Tingting Wang Hongyan Ji Huixia Yang Liangguang Jia Xu Han Jingsi Qiao Yu Zhang Liwei Liu Hong-Jun Gao Yeliang Wang School of Integrated Circuits and electronics&Yangtze Delta Region academy Beijing Institute of TechnologyBeijingthe People's Republic of China institute of Physics Chinese Academy of SciencesBeijingthe People's Republic of China

Advanced atomic tracking techniques play a critical role in characterizing structural evolution,elucidating fundamental mechanisms of exotic phenomena and tailoring delicate *** driven structural modulation in 2D crystals,such as the charge density wave(CDW),often leads to intriguing quantum properties,making them a valuable platform for exploring fundamental physics and potential device ***,despite their significance,experimental studies addressing atomic tracking of thermally-driven structural evolution in 2D crystals have been ***,we utilize high-accuracy variable-temperature atomic tracking measurements with scanning tunneling microscopy(STM)to directly observe a series of structural transitions in a model 2D crystal,namely NbSe_(2).With the atomic tracking technique,we confirm the existence of the universal thermally-driven CDW transition hysteresis between the heating and cooling *** transition hysteresis,characterized by a constant temperature offset,represents a new phenomenon of structural *** findings provide a feasible method to track CDW transitions at the atomic scale in 2D crystals,significantly contributing to a better understanding and the potential modulation of these materials'functions in nanodevices.

关键词： 2D crystal atomic tracking technique structural evolution temperature hysteresis

SAT-Based Automatic Searching for Differential and Linear Trails: Applying to CRAX

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Chinese Journal of electronics 2024年第1期33卷 72-79页

作者： Yiyi HAN Caibing WANG Zhongfeng NIU Lei HU State Key Laboratory of Information Security Institute of Information Engineering Chinese Academy of Sciences School of Cyber Security University of Chinese Academy of Sciences

Boolean satisfiability problem(SAT) is now widely applied in differential cryptanalysis and linear cryptanalysis for various cipher *** generated many excellent results for some ciphers,for example,*** this research,we study the differential and linear propagations through the operations of addition,rotation and XOR(ARX),and construct the SAT *** apply the models to CRAX to search differential trails and linear trails *** this sense,our contnbution can be broadly divided into two *** give the bounds for differential and linear cryptanalysis of Alzette both up to 12 steps,by which we present a 3-round differential attack and a 3-round linear attack for *** construct a 4-round key-recovery attack for CRAX with time complexity289times of 4-round encryption and data complexity 225.

关键词： Ciphers Encryption Complexity theory Time complexity

Classification of knowledge graph completeness measurement techniques

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Journal of Systems Engineering and electronics 2024年第1期35卷 154-162页

作者： ZHANG Ying XIAO Gang institute of Systems Engineering Academy of Military SciencesBeijing 100107China

At present,although knowledge graphs have been widely used in various fields such as recommendation systems,question and answer systems,and intelligent search,there are always quality problems such as knowledge omissions and *** assessment and control,as an important means to ensure the quality of knowledge,can make the applications based on knowledge graphs more complete and more accurate by reasonably assessing the knowledge graphs and fixing and improving the quality problems at the same ***,as an indispensable part of the knowledge graph construction process,the results of quality assessment and control determine the usefulness of the knowledge *** them,the assessment and enhancement of completeness,as an important part of the assessment and control phase,determine whether the knowledge graph can fully reflect objective phenomena and reveal potential connections among *** this paper,we review specific techniques of completeness assessment and classify completeness assessment techniques in terms of closed world assumptions,open world assumptions,and partial completeness *** purpose of this paper is to further promote the development of knowledge graph quality control and to lay the foundation for subsequent research on the completeness assessment of knowledge graphs by reviewing and classifying completeness assessment techniques.

关键词： quality assessment completeness assessment closed world assumptions open world assumption partial completeness assumption

The Exchange Attack and the Mixture Differential Attack Revisited: From the Perspective of Automatic Evaluation

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Chinese Journal of electronics 2024年第1期33卷 19-29页

作者： Kexin QIAO Zhiyu ZHANG Zhongfeng NIU Liehuang ZHU School of Cyberspace Science and Technology Beijing Institute of Technology State Key Laboratory of Cryptology institute of Information Engineering Chinese Academy of Sciences School of Cryptography University of Chinese Academy of Sciences

Recent results show that the differential properties within quadruples boom as a new inspiration in cryptanalysis of Advanced Encryption Standard(AES)-like constructions. These methods include the exchange attack proposed in Asiacrypt’19, the mixture differential attack proposed in To SC’18, etc., where the essential properties are obtained by manually scrutinizing the structures of the AES-like constructions. This paper presents a novel framework and an automatic tool based on mixed integer linear programming to search for mixture differential distinguishers for general constructions. This framework considers what equality patterns among quadruples can make a distinguisher and traces how the patterns propagate through cipher components with accurate probability *** this tool, a 5-round AES distinguishing attack with lower complexity and more 6-round distinguishing attacks in the chosen plaintext scenarios are deduced. We prove that no exchange-type or mixture differential distinguisher exists for 7 and above rounds AES if the details of the Sbox and Mix Columns matrix are not taken into account.

关键词： Ciphers Estimation Encryption Mixed integer linear programming Complexity theory Standards

Online Monitoring Method for Junction Temperature of SiC MOSFETs based on Temperature Sensitive Electrical Parameter

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CSEE Journal of Power and Energy Systems 2024年第4期10卷 1799-1807页

作者： Han Cao Puqi Ning Yunhao Huang Xuhui Wen Wuhan Second Ship Design and Research institute Wuhan 430205China Key Laboratory of Power electronics and Electric Drive Institute of Electrical EngineeringChinese Academy of SciencesBeijing 100190China institute of Electrical Engineering Chinese Academy of SciencesBeijing 100190China University of Chinese academy of sciences Beijing 100049China Collaborative Innovation Center of Electric Vehicles in Beijing Beijing 100081China

Compared to Si devices,the junction temperature of SiC devices is more critical due to the reliability concern introduced by immature packaging technology applied to new *** paper proposes a practical SiC MOSFET junction temperature monitoring method based on the on-state voltage$\\boldsymbol{V}_{\\mathbf{ds}(\\mathbf{on})}$*** Section II of the paper,the temperature sensitivity of the on-state voltage$\\boldsymbol{V}_{\\mathbf{ds}(\\mathbf{on})}$is *** hardware of the measurement system is set up in Section III,which consists of an On-state Voltage Measurement Circuit(OVMC),the sampling and isolation ***,a calibration method based on the self-heating of the SiC MOSFET chip is presented in Section *** the final Section,the junction temperature is monitored synchronously according to the calibration *** proposed method is applied to a Buck converter and verified by both an Infrared Radiation(IR)camera and a Finite Element Analysis(FEA)tool.

关键词： Junction temperature Silicon Carbide(SiC)MOSFET TSEP