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Chinese Journal of Chemical Physics 2009年第1期22卷 75-81页

作者： Xing-bao Wang Xian-xing Chi school of Physics and electronic information Wenzhou University Wenzhou 325027 China

Through the theoretical calculation of structural optimization, vibrational frequencies and atomization energies with one method of density functional theory （B3LYP） and two post- Hartree-Fock approaches （MP2, CCSD（T））, several stable isomers for new three pnictogen dianionic Sb4^2-, Bi4^2-, and （SbBi）2^2- species were determined. For two homoatomic Sb4^2- and Bi4^2- species, there are three stable isomers： square （D4h）, roof-shaped （C2v-1）, and C2v-2 structure with the square isomer being the ground state. For the heteroatomic dian- ionic （SbBi）2^2- species, there are also three stable isomers： rhombus （D2h）, roof-shaped （C1）, and C2v structures with the rhombic isomer being the ground state. The calculated NICS values show that nucleus-independent chemical shifts （NICS） values of roof-shaped isomers for Sb4^2-, Bi4^2-, and （SbBi）2^2- species are all negative, consequently indicating that these roof-shaped isomers possess aromaticities. NICS values for the planar ring isomers are all positive, suggesting that these three planar ring isomers have antiaromatic characters. The aromaticity for the two stable roof-shaped and square isomers are preliminarily explained and discussed with MO analysis.

关键词： Pnictogen cluster Ab initio Aromaticity Nucleus-independent chemical shift

Spatial and Excitation Variations for Different Applied Voltages in an Atmospheric Neon Plasma Jet

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Plasma Science and Technology 2016年第9期18卷 912-917页

作者：杨兰兰屠彦俞永波户玎岚张雄 school of electronic Science and engineering Southeast University

A neon plasma jet was generated in air, driven by a 9 kHz sinusoidal power supply. The characteristics of the plasma plume and the optical spectra with plasma propagation for different applied voltages were investigated. By increasing the applied voltage, the plasma plume first increases and then retracts to become short and bulky. The shortened effect of Ne plasma plume （about 10 mm） for the further voltage increasing is more apparent than that of He （about 3 mm） and Ar （about 1 mm）. Emission intensity of the N2 （337 am） increases with the applied voltage, gradually substituting the emission intensity of Ne （702 nm and 585 am） as the noticeable radiation. At the nozzle opening, the Ne （702 am） emission dominates, while the Ne （585 nm） emission is most noticeable around the tip of the plasma plume. The spatial distribution of the three spectral lines indicates that Ne （702 nm） emission decreases dramatically with plasma propagation while Ne （585 am） and N2 （337 nm） emissions reach their maxima at the middle of the plasma plume. The results indicate that the Ne （702 nm） emission is much more sensitive to the average electron temperature and the density of the high-energy electrons, so it changes greatly at the tube nozzle and little at the tip region as the voltage increases. The population of high-energy electrons, the average electron temperature, the collision with air molecules and the Penning effect between Ne metastables and air molecules may explain their different variations with plasma propagating and voltage increasing.

关键词： neon plasma jet optical spectrum plasma plume emission variation

Relevant experience learning:A deep reinforcement learning method for UAV autonomous motion planning in complex unknown environments

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Chinese Journal of Aeronautics 2021年第12期34卷 187-204页

作者： Zijian HU Xiaoguang GAO Kaifang WAN Yiwei ZHAI Qianglong WANG school of electronic and information Northwestern Polytechnical UniversityXi'an 710129China

Unmanned Aerial Vehicles(UAVs)play a vital role in military *** a variety of battlefield mission scenarios,UAVs are required to safely fly to designated locations without human ***,finding a suitable method to solve the UAV Autonomous Motion Planning(AMP)problem can improve the success rate of UAV missions to a certain *** recent years,many studies have used Deep Reinforcement Learning(DRL)methods to address the AMP problem and have achieved good *** the perspective of sampling,this paper designs a sampling method with double-screening,combines it with the Deep Deterministic Policy Gradient(DDPG)algorithm,and proposes the Relevant Experience Learning-DDPG(REL-DDPG)*** REL-DDPG algorithm uses a Prioritized Experience Replay(PER)mechanism to break the correlation of continuous experiences in the experience pool,finds the experiences most similar to the current state to learn according to the theory in human education,and expands the influence of the learning process on action selection at the current *** experiments are applied in a complex unknown simulation environment constructed based on the parameters of a real *** training experiments show that REL-DDPG improves the convergence speed and the convergence result compared to the state-of-the-art DDPG algorithm,while the testing experiments show the applicability of the algorithm and investigate the performance under different parameter conditions.

关键词： Autonomous Motion Planning(AMP) Deep Deterministic Policy Gradient(DDPG) Deep Reinforcement Learning(DRL) Sampling method UAV

Hyperspectral Image Super-Resolution Meets Deep Learning:A Survey and Perspective

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IEEE/CAA Journal of Automatica Sinica 2023年第8期10卷 1668-1691页

作者： Xinya Wang Qian Hu Yingsong Cheng Jiayi Ma the electronic information school Wuhan UniversityWuhan 430072China IEEE

Hyperspectral image super-resolution,which refers to reconstructing the high-resolution hyperspectral image from the input low-resolution observation,aims to improve the spatial resolution of the hyperspectral image,which is beneficial for subsequent *** development of deep learning has promoted significant progress in hyperspectral image super-resolution,and the powerful expression capabilities of deep neural networks make the predicted results more ***,several latest deep learning technologies have made the hyperspectral image super-resolution method ***,a comprehensive review and analysis of the latest deep learning methods from the hyperspectral image super-resolution perspective is *** this end,in this survey,we first introduce the concept of hyperspectral image super-resolution and classify the methods from the perspectives with or without auxiliary ***,we review the learning-based methods in three categories,including single hyperspectral image super-resolution,panchromatic-based hyperspectral image super-resolution,and multispectral-based hyperspectral image ***,we summarize the commonly used hyperspectral dataset,and the evaluations for some representative methods in three categories are performed qualitatively and ***,we briefly introduce several typical applications of hyperspectral image super-resolution,including ground object classification,urban change detection,and ecosystem ***,we provide the conclusion and challenges in existing learning-based methods,looking forward to potential future research directions.

关键词： Deep learning hyperspectral image image fusion image super-resolution survey

SuperFusion: A Versatile Image Registration and Fusion Network with Semantic Awareness

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IEEE/CAA Journal of Automatica Sinica 2022年第12期9卷 2121-2137页

作者： Linfeng Tang Yuxin Deng Yong Ma Jun Huang Jiayi Ma electronic information school Wuhan UniversityWuhan 430072China IEEE

Image fusion aims to integrate complementary information in source images to synthesize a fused image comprehensively characterizing the imaging scene. However, existing image fusion algorithms are only applicable to strictly aligned source images and cause severe artifacts in the fusion results when input images have slight shifts or deformations. In addition,the fusion results typically only have good visual effect, but neglect the semantic requirements of high-level vision *** study incorporates image registration, image fusion, and semantic requirements of high-level vision tasks into a single framework and proposes a novel image registration and fusion method, named Super Fusion. Specifically, we design a registration network to estimate bidirectional deformation fields to rectify geometric distortions of input images under the supervision of both photometric and end-point constraints. The registration and fusion are combined in a symmetric scheme, in which while mutual promotion can be achieved by optimizing the naive fusion loss, it is further enhanced by the mono-modal consistent constraint on symmetric fusion outputs. In addition, the image fusion network is equipped with the global spatial attention mechanism to achieve adaptive feature integration. Moreover, the semantic constraint based on the pre-trained segmentation model and Lovasz-Softmax loss is deployed to guide the fusion network to focus more on the semantic requirements of high-level vision tasks. Extensive experiments on image registration, image fusion,and semantic segmentation tasks demonstrate the superiority of our Super Fusion compared to the state-of-the-art *** source code and pre-trained model are publicly available at https://***/Linfeng-Tang/Super Fusion.

关键词： Global spatial attention image fusion image registration mutual promotion semantic awareness

Shaped beam pattern synthesis with desired nulling level and minimum sidelobe level

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Journal of electronic Science and Technology 2023年第1期21卷 35-45页

作者： Li-Ming Xu Qiang-Jian Song Shi-Wen Lei Bo Chen Jing Tian Hao-Quan Hu Southwest China Research Institute of electronic Equipment Chengdu610000China school of information and Communication engineering University of Electronic Science and Technology of ChinaChengdu611731China school of electronic Science and engineering University of Electronic Science and Technology of ChinaChengdu611731China

For the anti-interference/denoise purpose,it usually requires minimizing the sidelobe level(SLL)of a wide-beam pattern with a desired low nulling level(NL)in the nulling *** realize such an objective,the shaped-beam pattern synthesis(SBPS)is the most commonly used ***,since the SBPS problem focuses on synthesizing a predetermined beam shape,the minimum SLL via this approach cannot ensure to obtain the maximum power ***,it cannot obtain the lowest SLL with a certain power gain *** on such consideration,this paper tries to further minimize SLL of a wide-beam pattern with a desired low NL nulling region,by solving the power gain pattern synthesis(PGPS)*** PGPS problem selects the array excitation by directly optimizing the power ***,it has the potential to reduce SLL,when achieving the equal mainlobe power gain constraint via *** iterative algorithm which converts the primal optimization problem into convex sub-problems is proposed,resulting in an effective problem-solving *** simulations demonstrate the proposed algorithm can obtain about 10-dB lower SLL than the existing algorithms.

关键词： Array synthesis Minimum sidelobe level(SLL) Nulling level(NL) Pattern synthesis Wide-beam

不同尺寸橡胶/帘线H型拉拔试验界面参数的归一化处理评价方法

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Acta Mechanica Sinica 2024年第3期40卷 99-108页

作者：王琮文肖驰代玉静王君马寒松郇勇郇彦 State Key Laboratory of Nonlinear Mechanics(LNM) Institute of MechanicsChinese Academy of SciencesBeijing100190China school of engineering Science University of Chinese Academy of SciencesBeijing100049China school of Aerospace engineering Beijing Institute of TechnologyBeijing100081China State Key Laboratory of Polymer Physics and Chemistry and Polymer Composite engineering Laboratory Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China

H型拉拔试验被广泛应用于橡胶/帘线复合材料界面粘结强度的估算.然而,目前的国际标准只要求在橡胶/帘线H型拉拔试验中记录拔出力的大小,并强调从不同尺寸的样品中获得的结果不具有可比性.在本文中,我们研究了不同尺寸橡胶/帘线试验样品... 详细信息

H型拉拔试验被广泛应用于橡胶/帘线复合材料界面粘结强度的估算.然而,目前的国际标准只要求在橡胶/帘线H型拉拔试验中记录拔出力的大小,并强调从不同尺寸的样品中获得的结果不具有可比性.在本文中,我们研究了不同尺寸橡胶/帘线试验样品的H拔出结果的可比性,并提出了一种归一化的评价方法来处理这些结果.分别对尺寸为5 mm、6.4 mm、10 mm的试验样品进行橡胶/帘线H拉拔试验(尺寸为7.5 mm、8.5 mm的试件结果作为支撑性试验).在试验结果的基础上,采用有限元法内聚单元模型对界面粘结强度进行了分析,所得出的内聚力参数比国际标准中所规定的拔出力更能准确地反映界面粘结性能.因此,采用内聚单元法能够更合理地比较不同橡胶/帘线试样的界面粘结强度.我们首先基于6.4 mm尺寸样品的试验结果建立有限元模型,并确定满足条件的内聚单元参数,然后将其应用于其他尺寸的样品模型.尽管试验样品的尺寸大小在变化,但在保持内聚单元参数不变的前提下,模拟结果与试验结果仍然保持良好的一致性,这表明内聚参数不受样本尺寸的影响.在此基础上,我们提出了一种归一化方法,使不同尺寸样品的橡胶/帘线H拉拔试验的结果具有了可比性.本文提出的归一化方法是对现有国际、国内标准实验方法的扩展.

关键词： Rubber Composites Finite element method Cohesive elements H pull-out test

Resource Allocation and Trajectories Design for UAV-Assisted Jamming Cognitive UAV Networks

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China Communications 2022年第5期19卷 206-217页

作者： Zhenhui Tao Fuhui Zhou Yuhao Wang Xiaodong Liu Qihui Wu school of information engineering Nanchang UniversityNanchang 330031China College of electronic and information engineering Nanjing University of Aeronautics and AstronauticsNanjing 210000China Shanxi Key Laboratory of information Communication Network and Security Xi’an University of Posts and TelecommunicationXi’an 710121China school of electronic information Wuhan UniversityWuhan 430072China

Unmanned aerial vehicle(UAV)communications are subject to the severe spectrum scarcity *** UAV networks are promising to tackle this issue while the confidential information is susceptible to be eavesdropped.A UAV jamming assisted scheme is proposed.A joint resource allocation and trajectories optimization problem is formulated in a UAV-assisted jamming cognitive UAV network subject to diverse power and trajectory *** alternative optimization algorithm is proposed to solve the challenging non-convex joint optimization *** simulation results demonstrate the superiority of our proposed scheme and many meaningful insights are obtained for the practical design of cognitive UAV networks.

关键词： cognitive radio unmanned aerial vehicles communications physical layer security cooperative jamming

Secure control and filtering for industrial metaverse

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Frontiers of information Technology & electronic engineering 2024年第2期25卷 179-181页

作者： Qing-Long HAN Derui DING Xiaohua GE school of Science Computing and Engineering TechnologiesSwinburne University of TechnologyMelbourneVIC 3122Australia Department of Control Science and engineering University of Shanghai for Science and TechnologyShanghai 200093China

Metaverse can be regarded as a socialized and virtualized cyberspace parallel yet interactive to the real *** from the rapid development of cloud computing and digital twins,metaverse is transforming traditional control and filtering para‐digms of industrial automation systems into cyberphysical social *** this scenario,future industrial automation systems could be an integration of real-world ones and virtual twins combined with great computational power within a certain temporal and spatial range.

关键词： interactive filtering Secure

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