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SSA and BPNN Based Efficient Situation Prediction Model for Cyber Security

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SSA and BPNN Based Efficient Situation Prediction Model for ...

International Conference on Mobile Ad-hoc and Sensor Networks, MSN

作者： Minglong Cheng Guoqing Jia Weidong Fang Zhiwei Gao Wuxiong Zhang College of Physics and Electronic Information Engineering Qinghai Minzu University Xining P. R. China Science and Technology on Micro-System Laboratory Shanghai Institute of Micro-system and Information Technology Chinese Academy of Sciences Shanghai P. R. China University of Chinese Academy of Sciences Beijing P. R. China Shanghai Research and Development Center for Micro-Nano Electronics Shanghai P. R. China Ceprei Certification Body the Fifth Electronics Research Institute of Ministry of Industry and Information Technology

Establishing an effective situation prediction model for cyber security can know the active situation of future network malicious events in advance, which plays a vital role in cyber security protection. However, traditional models cannot achieve sufficient prediction accuracy when predicting cyber situations. To solve this problem, the initial location information of the sparrow population is optimized, and a sparrow search algorithm based on the Tent map is proposed. Then, the BP neural network is optimized using the improved sparrow search algorithm. Finally, a situation prediction model based on the sparrow search algorithm and BP neural network is proposed, namely T-SSA-BPNN. The simulation results show that the convergence speed and global search ability of the prediction model are improved. It can effectively predict the network security situation with high accuracy.

关键词： Computational modeling Simulation Neural networks Sociology Predictive models Prediction algorithms Search problems

Tailoring the Anomalous Hall Effect in Van Der Waals Ferromagnet Fe3gete2

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SSRN 2024年

作者： Wu, Kaile Wang, Qin Wang, Junshan Jiang, Jiaolin Zhao, Tian Zhao, Dong Han, Dan Quan, Zhiyong Ma, Zongmin Wang, Haomin Sang, Shengbo Ge, Yang Shanxi Key Laboratory of Micro Nano Sensors & Artificial Intelligence Perception College of Electronic Information and Optical Engineering Taiyuan University of Technology Taiyuan030024 China Key Lab of Advanced Transducers and Intelligent Control System The Ministry of Education Taiyuan University of Technology Taiyuan030024 China College of Materials Science and Engineering Taiyuan University of Technology Taiyuan030024 China Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of Education School of Chemistry and Materials Science Shanxi Normal University Taiyuan030031 China State Key Laboratory of Dynamic Measurement Technology North University of China Shanxi Taiyuan030051 China School of Semiconductor and Physics North University of China Shanxi Taiyuan030051 China State Key Laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai200050 China Shanxi Research Institute of 6D Artificial Intelligence Biomedical Science Taiyuan030024 China

Two-dimensional van der Waals magnetic materials have shown fascinating natural ferromagnetic properties at the atomic level, which has great potential in fields of low power spintronics, quantum computing and optical communication. Herein, the ferromagnetism and magnetic anisotropy of bulk Fe3GeTe2 (FGT) were investigated, and the testing results indicate a pronounced vertical magnetic anisotropy below the Curie temperature (Tc=165 K) of FGT. In addition, the anomalous Hall effect of FGT nanoflakes was studied at various temperatures and thicknesses by standard Hall bar device in detail. The results show the anomalous Hall resistance (0.764 Ω at 20 K decreased to 0.332 Ω at 140 K) and the obvious rectangular magnetic hysteresis rings below Tc (165 K). Furthermore, we calculated the carrier concentration (2.5×1022 cm-3 at 20K) and mobility (13.3 cm2/(v·s) at 20K) under large magnetic field (-6 T~6 T). Particularly, we demonstrated that the strong tailoring ability of the anomalous Hall effect for FGT-based magnetoelectric transport devices comes form the regulation of magnetic moment by sample thickness and magnetic field angle. The above experimental results verify that FGT is expected to be a prime candidate material for ultrathin 2D spintronic devices to the next generation. © 2024, The Authors. All rights reserved.

关键词： Germanium alloys

Application of the High-Q Bouncing Ball Model Based on Fabry-Pérot Cavity for Alcohol Gas Concentration Detection

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SSRN 2023年

作者： Sang, Luxiao Wang, Teng Zhao, Biao Ding, Jinyu Jian, Aoqun Sang, Shengbo Shanxi Key Laboratory of Micro Nano Sensors & Artificial Intelligence Perception College of Electronic Information and Optical Engineering Taiyuan University of Technology Taiyuan030024 China Key Lab of Advanced Transducers and Intelligent Control System Ministry of Education Taiyuan University of Technology Taiyuan030024 China Shanxi Research Institute of 6D Artificial Intelligence Biomedical Science Taiyuan030031 China

This paper presents a method to enhance the Q factor of Fabry-Pérot cavities using a vertical dielectric interface (DI) made of silicon and air, which generates a bouncing ball model. The method is applied to detect alcohol gas concentrations with high resolution. Specifically, we introduce a 450 µm-thick silicon wafer into the Fabry-Pérot (FP) cavity, where it is positioned at an angle of inclination. This addition considerably augments the light-matter interaction, effectively confining the light within the cavity. The Q factor of the FP cavity with DI is always higher than that of the open FP cavity in the inclination angle range of 0 to 1°. Moreover, the effective mode area of the FP cavity with DI is smaller. Furthermore, the FP cavity with DI reduces the effective mode area and diminishes the lateral walk-off loss experienced in the open FP cavity. Finally, we experimentally verified the effectiveness of this method by detecting alcohol gas concentrations ranging from 28.5 ppm to 142.5 ppm and achieving a Q factor improvement from 5.9×104 to 1.2×105. The system sensitivity was calculated to be 0.5294 pm/ppm, and the resolution obtained was 28.5 ppm. © 2023, The Authors. All rights reserved.

关键词： Silicon wafers

Reliable and Broad-range Layer Identification of Au-assisted Exfoliated Large Area MoS2 and WS2 Using Reflection Spectroscopic Fingerprints

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arXiv

arXiv 2022年

作者： Zou, Bo Zhou, Yu Zhou, Yan Wu, Yanyan He, Yang Wang, Xiaonan Yang, Jinfeng Zhang, Lianghui Chen, Yuxiang Zhou, Shi Guo, Huaixin Sun, Huarui School of Science Ministry of Industry and Information Technology Key Laboratory of Micro-Nano Optoelectronic Information System Harbin Institute of Technology Shenzhen518055 China Collaborative Innovation Center of Extreme Optics Shanxi University Shanxi Taiyuan030006 China State Key Laboratory of Superlattices and Microstructures Institute of Semiconductors Chinese Academy of Sciences Beijing100083 China University of Science and Technology of China Hefei230026 China Science and Technology on Monolithic Integrated Circuits and Modules Laboratory Nanjing Electronic Devices Institute Nanjing210016 China

The emerging Au-assisted exfoliation technique provides a wealth of large-area and high-quality ultrathin two-dimensional (2D) materials compared with traditional tape-based exfoliation. Fast, damage-free, and reliable determination of the layer number of such 2D films is essential to study layer-dependent physics and promote device applications. Here, an optical method has been developed for simple, high throughput, and accurate determination of the layer number for Au-assisted exfoliated MoS2 and WS2 films in a broad thickness range. The method is based on quantitative analysis of layer-dependent white light reflection spectra, revealing that the reflection peak intensity can be used as a clear indicator for determining the layer number. The simple yet robust method will facilitate the fundamental study on layer-dependent optical, electrical, and thermal properties and device applications of 2D materials. The technique can also be readily combined with photoluminescence and Raman spectroscopies to study other layer-dependent physical properties of 2D materials. Copyright © 2022, The Authors. All rights reserved.

关键词： Layered semiconductors

Magnetic Properties of Nh4Al(SO4)2·12H2O: Evidence of Spin Glass Behavior Based on Proton Orbitals

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SSRN 2021年

作者： Meng, Lei Peng, Chu Xin He, Chen Yen, Fei State Key Laboratory on Tunable Laser Technology Ministry of Industry and Information Technology Key Laboratory of Micro-Nano Optoelectronic Information System the School of Science Harbin Institute of Technology Shenzhen University Town Shenzhen Guangdong518055 China

The polarity of the magnetic susceptibility χ(T) of ammonium alum Nh4Al(SO4)2·12H2O single crystals below its ferroelectric Curie temperature TC is identified to depend only on the cooling rate. To explain this, we consider reorienting distorted NH4+ to carry weak magnetic and electric dipole moments that are linearly coupled. Slow cooling allows the dipole moments to align which enhances χ(T) to become positive. However, due to energy degeneracy of rotational motion and geometric frustration of the NH4+, faster cooling rates render the system to become an orientational glass state causing χ(T) to remain negative. These weak and misaligned molecular magnets are 10-1000 times more sensitive to ac magnetic fields than conventional spin glasses according to ac susceptibility measurements. Specific heat measurements also show the presence of excess entropy below a negative anomaly near 53 K. Our findings identify a new class of non-equilibrium system with potential applications in non-volatile memory devices. © 2021, The Authors. All rights reserved.

关键词： Magnetic susceptibility

Volatile to Non-Volatile Switching Transition in Chalcogenides

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Advanced Functional Materials 2025年第23期35卷

作者： Zhao, Zihao Zhang, Mengfei Yang, Qun Gotoh, Tamihiro Ge, Qingqin Shi, Nannan Sun, Yuting Zhao, Jiayi Sui, Yanping Jiang, Ran Yu, Haibin Elliott, Stephen R. Song, Zhitang Zhu, Min National Key Laboratory of Materials for Integrated Circuits Shanghai Institute of Micro-System and Information Technology Chinese Academy of Sciences Shanghai200050 China University of Chinese Academy of Sciences Beijing100029 China Wuhan National High Magnetic Field Center and School of Physics Huazhong University of Science and Technology Wuhan430074 China Department of Physics Graduate School of Science and Technology Gunma University Maebashi3718510 Japan Thermo Fisher Scientific China Shanghai200050 China Faculty of Electrical Engineering and Computer Science Ningbo University Ningbo315211 China Trinity College University of Cambridge CambridgeCB2 1TQ United Kingdom Physical and Theoretical Chemistry Laboratory University of Oxford OxfordOX1 3QZ United Kingdom School of Integrated Circuits Shanghai Jiao Tong University Shanghai200240 China

Over the past 60 years, three distinct electrical switching behaviors have been discovered in chalcogenides: ovonic threshold switch (OTS), ovonic memory switch (OMS), and phase-change switch (PCS). The first two have been successfully utilized in commercialized 3D Xpoint chips, serving as selector and memory cells, respectively. However, the relationships among these three behaviors remain unclear. Here, it is demonstrated that the Ge-Te binary system exhibits these three switching mechanisms. Specifically, the switching behavior transforms from PCS-like to OTS-like within the composition range from GeTe8 to GeTe6, while the shift from volatile (OTS) to non-volatile switching behavior (OMS) occurs between the compositions GeTe2 and GeTe. The PCS-to-OTS transition is primarily driven by enhancements in glass-forming ability, with the Turnbull parameter increasing from 0.58 to 0.6, and the crystallization temperature exceeding 145 °C, while the shift from OTS to OMS behavior is largely due to the significantly accelerated crystallization speed, from microseconds to nanoseconds. Most importantly, the GeTe16 PCS stands out, with a large ON current (0.6 mA), low leakage current (−8 A), high endurance (>6 × 109 cycles), and high-temperature back-end-of-line compatibility. The crystalline nature of this PCS material addresses the composition and toxicity issues in conventional OTS materials. Moreover, GeTe16 PCSs have been successfully integrated with GeTe OMSs, forming selector/memory arrays with a read margin of 0.4 V. These findings not only reveal the mechanisms underlying the volatile to non-volatile transition but also provide an alternative solution for high-density 3D memory, potentially replacing the OTS/OMS stack approach. © 2025 Wiley-VCH GmbH.

关键词： Phase change memory

Dynamic Re-Construction Of Sulfur Tailored Cu2o for Efficient Electrochemical Co2 Reduction to Formate Over a Wide Potential Window

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SSRN 2022年

作者： Yuan, Hefeng Liu, Zhehao Sang, Shengbo Wang, Xiaoguang Micro Nano System Research Center College of Information and Computer Taiyuan University of Technology Shanxi Taiyuan030024 China Laboratory of Advanced Materials and Energy Electrochemistry College of Materials Science & Engineering Taiyuan University of Technology Shanxi Taiyuan030024 China Shanxi Key Laboratory of Gas Energy Efficient and Clean Utilization Taiyuan University of Technology Shanxi Taiyuan030024 China

Formate is an important organic raw chemical generated in CO2 electroreduction process. In the present work, copper sulfide precursors with different initial morphologies (nanoparticles, nanowires and nanorods) were found to undergo significant microstructure reconstruction in electrochemical CO2 reduction process. The optimum S-Cu2O-14 catalyst can be finally transformed into nanoporous structure composed of quantities of nanoparticles, which simultaneously achieves an excellent faradaic efficiency of 67.2% and partial current density of 16.3 mA cm-2 at -1.0 V vs. RHE for formate. Due to the large electrochemical surface area and resultant nanoporous topography resulted from the reconstruction, S-Cu2O-14 catalyst is highly selective and stable, revealing an average 66.1% selectivity to formate for at least 20 h at the same potential. © 2022, The Authors. All rights reserved.

关键词： Sulfur

Dynamic Re-Construction Of Sulfur Tailored Cu2o for Efficient Electrochemical Co2 Reduction to Formate Over a Wide Potential Window

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SSRN 2022年

关键词： Sulfur

Hierarchical compositional ordering in lead-based perovskite relaxors

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Physical Review B 2023年第5期107卷 054101-054101页

作者： Yanxing Zhang Jiale Zhang Nan Zhang Laijun Liu Alexei A. Bokov Zuo-Guang Ye Dawei Wang School of Physics Henan Normal University Xinxiang 453007 China School of Microelectronics & State Key Laboratory for Mechanical Behavior of Materials Xi'an Jiaotong University Xi'an 710049 China Key Lab of Micro-Nano Electronics and System Integration of Xi'an City Xi'an Jiaotong University Xi'an 710049 China Electronic Materials Research Laboratory–Key Laboratory of the Ministry of Education and International Center for Dielectric Research Xi' an Jiaotong University Xi'an 710049 China Key Laboratory of Nonferrous Materials and New Processing Technology Ministry of Education College of Materials Science and Engineering Guilin University of Technology Guilin 541004 China Department of Chemistry and 4D LABS Simon Fraser University Burnaby British Columbia Canada V5A 1A6

Lead-based relaxor ferroelectric perovskites with the formula Pb(B1/3B2/3′)O3, such as Pb(Mg1/3Nb2/3)O3, can have different degrees of compositional ordering even for the same stoichiometry. Despite intensive investigation, determining the nature of the B and B′ ordering remains a challenging problem. Here, we reveal a hierarchical ordering in Pb(B1/3B2/3′)O3 on top of the well-known βI and βII sublattices, which is the first level of the proposed hierarchy. Such additional ordering, which is found by considering additional nearest neighboring interactions in the model enriches our understanding of the complex nature of the chemical ordering in lead-based ferroelectric relaxors. In addition, we show that Pb(Cd1/3Nb2/3)O3 has a higher degree of ordering than that of Pb(Mg1/3Nb2/3)O3 or Pb(Zn1/3Nb2/3)O3 in which antiphase domains exist, revealing the possible different degree of compositional ordering arising from intralattice ordering.

关键词： Order parameters Phase transitions Relaxor ferroelectrics Monte Carlo methods