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National Science Review 2024年第5期11卷 92-93页

作者： Minkyeong ban Jinwoo Lee Department of Chemical and Biomolecular Engineering Korea Advanced Institute of Science and Technology (KAIST)

Mesoporous metal oxide materials have attracted significant interest due to their porous frameworks and large surface areas, finding applications in sensors, catalysis and energy storage [1]. The performance of these materials is influenced by both their porous structures and the crystal phase of the frameworks [2].

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An Empirical Study on the Effectiveness of Adversarial Examples in Malware Detection

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 3535-3563页

作者： Younghoon ban Myeonghyun Kim Haehyun Cho School of Software Soongsil UniversitySeoul06978Korea

Antivirus vendors and the research community employ Machine Learning(ML)or Deep Learning(DL)-based static analysis techniques for efficient identification of new threats,given the continual emergence of novel malware *** the other hand,numerous researchers have reported that Adversarial Examples(AEs),generated by manipulating previously detected malware,can successfully evade ML/DL-based *** antivirus systems,in particular,have been identified as vulnerable to such *** paper firstly focuses on conducting black-box attacks to circumvent ML/DL-based malware *** attack method utilizes seven different perturbations,including Overlay Append,Section Append,and Break Checksum,capitalizing on the ambiguities present in the PE format,as previously employed in evasion attack *** directly applying the perturbation techniques to PE binaries,our attack method eliminates the need to grapple with the problem-feature space dilemma,a persistent challenge in many evasion attack *** a black-box attack,our method can generate AEs that successfully evade both DL-based and ML-based ***,AEs generated by the attack method retain their executability and malicious behavior,eliminating the need for functionality *** thorogh evaluations,we confirmed that the attack method achieves an evasion rate of 65.6%against well-known ML-based malware detectors and can reach a remarkable 99%evasion rate against well-known DL-based malware ***,our AEs demonstrated the capability to bypass detection by 17%of vendors out of the 64 on VirusTotal(VT).In addition,we propose a defensive approach that utilizes Trend Locality Sensitive Hashing(TLSH)to construct a similarity-based defense *** several experiments on the approach,we verified that our defense model can effectively counter AEs generated by the perturbation *** conclusion,our defense model alleviates the limitation of the mos

关键词： Malware classification machine learning adversarial examples evasion attack cybersecurity

A Wideband High-Gain Sawtooth Slot Array Antenna with Frequency-Scanning at Lower Frequency and Fixed-Beam at Higher Frequency

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Chinese Journal of Electronics 2024年第2期33卷 463-471页

作者： Qiang SUN Yongling ban Jun HU School of Electronic Science and Engineering University of Electronic Science and Technology of China

Exploring the multifunctional array antenna suitable for complex communication environment has very important research value. In this paper, a millimeter wave(mm-wave) double longitudinal sawtooth slot array antenna(DLSA) based on substrate integrated waveguide(SIW) technology is proposed, which has wideband, highgain and novel beam characteristics. Two irregular longitudinal slots are etched on the SIW conductor surface as the radiation structure. To improve the bandwidth of the DLSA, the metallized vias are added at the transition point of the slots to construct multiple resonant frequency points. By adjusting the size of the slots and the position of the metallized vias, the phase constant can be regulated, and the unusual beam characteristics can be obtained. That is to say, in the lower frequency band, the beam pointing angle increases with frequency. In the higher frequency band,the beam pointing angle is maintained at a fixed angle. Finally, to improve the antenna gain, a 16 × 8 DLSA is fabricated, measured and discussed. The proposed antenna has an impedance matching bandwidth close to 9.7 *** 27 to 33 GHz, the beam pointing angle changes from 8° to 29°. From 33 to 37 GHz, the beam pointing angle is fixed at 29°, and the pointing angle error range is ±1°. In addition, the measured maximum gain is 22.9 d Bi at32 GHz.

关键词： Antenna measurements Slot antennas Surface waves Resonant frequency Gain measurement Conductors Frequency measurement

A review of MXene-derived quantum dots:Synthesis,characterization,properties,and applications

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Particuology 2024年第8期91卷 50-71页

作者： Chunhe Zhou Kar ban Tan Wenjuan Han Li Wang Ming Lu The Joint Laboratory of MXene Materials Key Laboratory of Functional Materials Physics and Chemistry of the Ministry of EducationJilin Normal UniversityChangchunJilin 130103China Department of Chemistry Faculty of ScienceUniversiti Putra MalaysiaSerdangSelangor 43400Malaysia

Cutting MXene to a minimum size and forming the derived two-dimensional MXene quantum dots(MQDs),which possess a unique intrinsic layered geometry structure,restricts exciton due to their novel spatial *** gives rise to a broad spectrum of fascinating properties,rendering them for various ***,the correlation between composition,structure,and processing control of MQDs is investigated systematically,giving further insight into the intrinsic and extrinsic *** review also provides an opportunity to explore new compositions,modify the properties,and tailor MQDs into the guided architectural design before any prospective applications.

关键词： MXene Quantum dots Characterization Properties Applications

The Adjustment Analysis Method of the Active Surface Antenna Based on Convolutional Neural Network

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Research in Astronomy and Astrophysics 2024年第6期24卷 294-306页

作者： You ban Shang Shi Na Wang Qian Xu Shufei Feng School of Mechanical Engineering Xinjiang UniversityUrumqi 830017China Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China School of Mechanical Engineering Dongguan University of TechnologyDongguan 523808China

Active surface technique is one of the key technologies to ensure the reflector accuracy of the millimeter/submillimeter wave large reflector *** antenna is complex,large-scale,and high-precision equipment,and its active surfaces are affected by various factors that are difficult to comprehensively deal *** this paper,based on the advantage of the deep learning method that can be improved through data learning,we propose the active adjustment value analysis method of large reflector antenna based on deep *** method constructs a neural network model for antenna active adjustment analysis in view of the fact that a large reflector antenna consists of multiple panels spliced *** on the constraint that a single actuator has to support multiple panels(usually 4),an autonomously learned neural network emphasis layer module is designed to enhance the adaptability of the active adjustment neural network *** classical 8-meter antenna is used as a case study,the actuators have a mean adjustment error of 0.00252 mm,and the corresponding antenna surface error is0.00523 *** active adjustment result shows the effectiveness of the method in this paper.

关键词： techniques:radar astronomy telescopes methods:analytical methods:numerical

Direct enantioselective reduction of C=C bond of β-polyfluoro-alkylated enones via asymmetric photoredox catalysis

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Science China Chemistry 2024年第6期67卷 2016-2021页

作者： Linghong Zhang Jin Ma Xu ban Xiaowei Zhao Yanli Yin Zhiyong Jiang Key Laboratory of Natural Medicine and Immuno-Engineering of Henan Province Henan UniversityKaifeng475004China School of Chemistry and Chemical Engineering Henan Normal UniversityPingyuan LaboratoryXinxiang453007China College of Advanced Interdisciplinary Science and Technology Henan University of TechnologyZhengzhou450001China

Direct enantioselective reduction of the C=C bond ofβ-polyfluoro-alkylated enones is an important but long-pending subject in asymmetric ***,we report on the viability of visible light-driven cooperative photoredox and chiral hydrogenbonding catalysis to effectively address this challenge,as a variety of products are obtained in high yields(up to 85%)with good to excellent enantioselectivities(up to 98%ee).The formation of thermodynamically favorable enol intermediates after double single-electron reduction represents the center of the ***,the utility of the current method is validated by the convenient regio-specific and-diverse synthesis of various deuterated derivatives for these products using inexpensive D_(2)O as the deuterium source.

关键词： photoredox catalysis Br?nsted acids asymmetric reduction enantioselective protonation azaarenes

Efficiency improvement by using metal–insulator‑semiconductor structure in InGaN/GaN micro‑light‑emitting diodes

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Frontiers of Optoelectronics 2024年第1期17卷 77-84页

作者： Jian Yin David Hwang Hossein Zamani Siboni Ehsanollah Fathi Reza Chaji Dayan ban Department of Electrical and Computer Engineering Waterloo Institute NanotechnologyUniversity of WaterlooWaterlooON N2L 3G1Canada Vuereal InC. 440 Philip StreetUnit 100WaterlooON N2L 5R9Canada

InGaN/GaN micro-light-emitting diodes(micro-LEDs)with a metal–insulator-semiconductor(MIS)structure on the sidewall are proposed to improve *** this MIS structure,a sidewall electrode is deposited on the insulating layer-coated sidewall of the device mesa between a cathode on the bottom and an anode on the ***(EL)measurements of fabricated devices with a mesa diameter of 10μm show that the application of negative biases on the sidewall electrode can increase the device external quantum efficiency(EQE).In contrast,the application of positive biases can decrease the *** band structure analysis reveals that the EQE is impacted because the application of sidewall electric fields manipulates the local surface electron density along the mesa sidewall and thus controls surface Shockley–Read–Hall(SRH)*** suggested strategies,reducing insulator layer thickness and exploring alternative materials,can be implemented to further improve the EQE of MIS micro-LEDs in future fabrication.

关键词： Micro-LED GaN EQE improvement Micro-fabrication

Constraints Separation Based Evolutionary Multitasking for Constrained Multi-Objective Optimization Problems

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IEEE/CAA Journal of Automatica Sinica 2024年第8期11卷 1819-1835页

作者： Kangjia Qiao Jing Liang Kunjie Yu Xuanxuan ban Caitong Yue Boyang Qu Ponnuthurai Nagaratnam Suganthan School of Electrical and Information Engineering Zhengzhou UniversityZhengzhou 450001China School of Electrical Engineering and Automation Henan Institute of TechnologyXinxiang 453003China School of Electronic and Information Zhongyuan University of TechnologyZhengzhou 450007China KINDI Center for Computing Research College of EngineeringQatar UniversityDoha 999043Qatar

Constrained multi-objective optimization problems(CMOPs)generally contain multiple constraints,which not only form multiple discrete feasible regions but also reduce the size of optimal feasible regions,thus they propose serious challenges for *** all constraints,some constraints are highly correlated with optimal feasible regions;thus they can provide effective help to find feasible Pareto ***,most of the existing constrained multi-objective evolutionary algorithms tackle constraints by regarding all constraints as a whole or directly ignoring all constraints,and do not consider judging the relations among constraints and do not utilize the information from promising single ***,this paper attempts to identify promising single constraints and utilize them to help solve *** be specific,a CMOP is transformed into a multitasking optimization problem,where multiple auxiliary tasks are created to search for the Pareto fronts that only consider a single constraint ***,an auxiliary task priority method is designed to identify and retain some high-related auxiliary tasks according to the information of relative positions and dominance ***,an improved tentative method is designed to find and transfer useful knowledge among *** results on three benchmark test suites and 11 realworld problems with different numbers of constraints show better or competitive performance of the proposed method when compared with eight state-of-the-art peer methods.

关键词： Constrained multi-objective optimization(CMOPs) evolutionary multitasking knowledge transfer single constraint.

重度骨关节炎人工全髋关节置换术中偏心距重建

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中国修复重建外科杂志 2014年第8期28卷 947-950页

作者：班照楠黄富国顾琪珊许冰李永奎李正疆四川大学华西医院骨科成都610041

目的探讨髋关节重度骨关节炎行人工全髋关节置换术（total hip arthroplasty，THA）中偏心距重建方法以及疗效。方法2009年7月－2011年6月，收治18例（18髋）髋关节重度骨关节炎患者。男14例，女4例；年龄47～72岁，平均55.4岁。病程11... 详细信息

目的探讨髋关节重度骨关节炎行人工全髋关节置换术（total hip arthroplasty，THA）中偏心距重建方法以及疗效。方法2009年7月－2011年6月，收治18例（18髋）髋关节重度骨关节炎患者。男14例，女4例；年龄47～72岁，平均55.4岁。病程11～74个月，平均33.6个月。左髋11例，右髋7例。髋关节Harris评分为（34.6 ± 5.3）分。托马斯征、“4”字试验以及Trendelenburg征均为阳性。术前肢体不等长15例。患者均行THA，术中采用股骨距标准截骨、选择正确的旋转中心及合适长度股骨距重建偏心距。结果术后切口均Ⅰ期愈合。1例出现腓总神经牵拉损伤，经对症治疗3个月后恢复；其余患者均无手术相关并发症发生。18例均获随访，随访时间30～53个月，平均43.5个月。术后髋关节疼痛明显缓解，步态恢复正常。X线片复查示：关节无脱位，假体在位良好、无松动；6例双下肢不等长。患者健、患侧偏心距差值为0.1～0.7 mm，平均0.4 mm。末次随访时，髋关节Harris评分为（83.0 ± 7.1）分，与术前比较差异有统计学意义（t= —22.96，P=0.01）；关节活动度均较术前显著提高，差异有统计学意义（P 〈 0.05）。结论髋关节重度骨关节炎行THA，通过术前模板测量选择合适假体，术中保留适当股骨距长度、调节股骨颈长度和颈干角，适度软组织松解，可准确重建偏心距，术后关节功能恢复满意。

关键词：重度骨关节炎人工全髋关节置换术偏心距重建