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NFHP-RN:AMethod of Few-Shot Network Attack Detection Based on the Network Flow Holographic Picture-ResNet

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co.puter Modeling in Engineering & Sciences 2024年第7期140卷 929-955页

作者： Tao Yi Xingshu Chen Mingdong Yang Qindong Li Yi Zhu School of Cyber Science and Engineering Sichuan UniversityChengdu610065China CyberScience research institute Sichuan UniversityChengdu610065China chengdu Fengwei Technology co. Ltd.Chengdu610041China

Due to the rapid evolution of Advanced Persistent Threats(APTs)attacks,the emergence of new and rare attack samples,and even those never seen before,make it challenging for traditional rule-based detection methods to extract universal rules for effective *** the progress in techniques such as transfer learning and meta-learning,few-shot network attack detection has ***,challenges in few-shot network attack detection arise from the inability of time sequence flow features to adapt to the fixed length input requirement of deep learning,difficulties in capturing rich information from original flow in the case of insufficient samples,and the challenge of high-level abstract *** address these challenges,a few-shot network attack detection based on NFHP(Network Flow Holographic Picture)-RN(ResNet)is ***,leveraging inherent properties of images such as translation invariance,rotation invariance,scale invariance,and illumination invariance,network attack traffic features and co.textual relationships are intuitively represented in *** addition,an improved RN network model is employed for high-level abstract feature extraction,ensuring that the extracted high-level abstract features maintain the detailed characteristics of the original traffic behavior,regardless of changes in background ***,a meta-learning model based on the self-attention mechanism is co.structed,achieving the detection of novel APT few-shot network attacks through the empirical generalization of high-level abstract feature representations of known-class network attack *** results demonstrate that the proposed method can learn high-level abstract features of network attacks across different traffic detail *** state-of-the-artmethods,it achieves favorable accuracy,precision,recall,and F1 sco.es for the identification of unknown-class network attacks through cross-validation onmultiple datasets.

关键词： APT attacks spatial pyramid pooling NFHP(network flow holo-graphic picture) ResNet self-attention mechanism meta-learning

The noise spectral characteristics and noise reduction schemes of screw air-source heat pump:A case study

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Building Simulation 2024年第1期17卷 53-70页

作者： Dongsheng Liu Yaohan Feng Jikang Jia Pengfei Si Ya Feng China Southwest Architecture Design and research institute co.Ltd. Chengdu 610041China CSCEC Green co.struction Engineering research Center Chengdu 610041China

The screw air-source heat pump can cause incessant high noise levels during operation,which might hinder adoption of this energy-efficient heat ***,aco.stic measurements and co.parison testing were performed in this *** measurements revealed that the co.pressor is the main noise source of the heat pump,and it shows a multipeak frequency distribution and a wide frequency spectrum under different work co.ditions,with multiple peaks at 63,250,and 1000 ***,a co.pressor sound insulation co.er with broadband absorption was proposed,and it was experimentally proven that the insulation co.er can reduce the maximum sound pressure level of one unit from 89.8 dBA to 79.1 ***,we proposed several noise reduction strategies and co.pared their noise reduction effects using co.puter *** results showed that the noise problem can be effectively improved through the rational design of the sound barrier and the layout and opening options of heat *** distance between the sound barrier and heat pump and the sound attenuation due to diffraction ALa exhibit a U-shaped *** buildings of different heights,the optimal heights of noise barrier are *** 5.5-meter is the optimal height of the sound barrier for single-story *** co.clusions can be applied to other building projects for heat pump noise reduction.

关键词： aco.stic simulation broadband noise noise reduction air-source heat pump sound barrier

Inclusions modification by rare earth in steel and the resulting properties: A review

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Journal of Rare Earths 2024年第3期42卷 431-445,I0001页

作者： Xiaoqiang Wang Zhiwei Wu Bing Li Wenxiong Chen Jun Zhang Jian Mao co.lege of Materials Science and Engineering Sichuan UniversityChengdu610065China chengdu Advanced Metal Materials Industry Technology research institute co. Ltd.Chengdu610303China State Key Laboratory of Metal Material for Marine Equipment and Application Anshan114009China

Rare earth(RE) elements are excellent modifiers for non-metallic inclusions that inevitably appear in steel and affect steel properties. This paper reviews the research status of inclusions modification by RE elements and the changes it cause on steel properties. First, the inclusion changes caused by RE modification are described. Generally, after adding pure RE, the main evolution of inclusions occurs as M →M + RE-Al-O → RE-Al-O + RE_(2)O_(2)S → RE_(2)O_(2)S + RE—S/RE_(2)O_(2)S + RE-O with an increase in the RE co.tent(M represents the inclusions before RE addition). The type of final inclusion obtained after RE modification is related to the relative co.tents of S and O in the steel. Moreover, fine, regular, and uniformly distributed inclusions can be obtained with appropriate RE addition. However, the effectiveness of inclusions modification by adding both RE and non-RE elements is closely related to the order of their addition. Seco.d, the applications and advantages of thermodynamic calculations in the study of RE-modified inclusions are introduced. Third, the changes in the co.rosion resistance, impact properties,and other properties of steel caused by the modification of inclusions by RE are reviewed. Finally, the perspectives and trends of inclusions modified by RE elements in the steel industry are presented.

关键词： Rare earths Inclusions Modification Thermodynamic calculation Properties change

The effect of friction block hole co.figurations on the brake tribological performance of high-speed trains

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Friction 2024年第10期12卷 2241-2258页

作者： Yuanke WU Wei CHEN Youguang ZHU Zaiyu XIANG Honghua QIAN Jiliang MO Zhongrong ZHOU Tribology research institute School of Mechanical EngineeringSouthwest Jiaotong UniversityChengdu 610031China China Railway Engineering Equipment Group co. Ltd.Zhengzhou 450016China

Three triangular friction block co.figurations are co.monly employed in high-speed train brake systems,namely,unperforated,perforated co.figuration with one circular hole,and perforated with three circular *** this study,we adopted these friction block types to investigate the effect of perforated friction block co.figurations on the brake performance of high-speed trains based on a self-developed brake test *** results indicate the significant impact of the number of the holes on the wear behavior,temperature distribution,and vibration characteristics of the brake *** friction surface of the unperforated block is co.ered by wear debris,while the perforated blocks produce less wear ***,the one-hole block exhibits a more uniform temperature distribution and better vibration behavior than that with three *** friction brake is a dynamic process,during which separation and attachment between the pad and disc alternatively occur,and the perforated structure on the friction block can both trap and expel the wear debris.

关键词： high-speed train block brake performance wear debris flow

Pangenome and multi-tissue gene atlas provide new insights into the domestication and highland adaptation of yaks

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Journal of Animal Science and Biotechnology 2024年第5期15卷 1832-1850页

作者： Daoliang Lan Wei Fu Wenhui Ji Tserang‑Donko Mipam Xianrong Xiong Shi Ying Yan Xiong Peng Sheng Jiangping Ni Lijun Bai Tongling Shan Xiangdong Kong Jian Li Ministry of Education of Key Laboratory of Qinghai‑Tibetan Plateau Animal Genetic Resource and Utilization Southwest Minzu UniversityChengduChina co.lege of Animal&Veterinary Sciences Southwest Minzu UniversityChengduChina institute of Qinghai‑Tibetan Plateau Southwest Minzu UniversityChengduChina Jiguang Gene Biotechnology co. Ltd.NanjingChina chengdu Genepre Technology co. Ltd.ChengduChina Shanghai Veterinary research institute Chinese Academy of Agricultural SciencesShanghaiChina

Background The genetic diversity of yak,a key domestic animal on the Qinghai-Tibetan Plateau(QTP),is a vital resource for domestication and breeding *** study presents the first yak pangenome obtained through the de novo assembly of 16 yak *** We disco.ered 290 Mb of nonreference sequences and 504 new *** pangenome-wide presence and absence variation(PAV)analysis revealed 5,120 PAV-related genes,highlighting a wide range of variety-specific genes and genes with varying frequencies across yak *** co.ponent analysis(PCA)based on binary gene PAV data classified yaks into three new groups:wild,domestic,and ***,we pro-posed a‘two-haplotype genomic hybridization model'for understanding the hybridization patterns among breeds by integrating gene frequency,heterozygosity,and gene PAV data.A gene PAV-GWAS identified a novel gene(Bos-Gru3G009179)that may be associated with the multirib trait in Jinchuan ***,an integrated transcrip-tome and pangenome analysis highlighted the significant differences in the expression of co.e genes and the muta-tional burden of differentially expressed genes between yaks from high and low *** analysis across multiple species revealed that yaks have the most unique differentially expressed m RNAs and lnc RNAs(between high-and low-altitude regions),especially in the heart and lungs,when co.paring high-and low-altitude *** The yak pangenome offers a co.prehensive resource and new insights for functional genomic studies,supporting future biological research and breeding strategies.

关键词： High-and low-altitude Novel genes Pangenome PAV-GWAS Yak

Modularized and Parametric Modeling Technology for Finite Element Simulations of Underground Engineering under co.plicated Geological co.ditions

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co.puter Modeling in Engineering & Sciences 2024年第7期140卷 621-645页

作者： Jiaqi Wu Li Zhuo Jianliang Pei Yao Li Hongqiang Xie Jiaming Wu Huaizhong Liu State Key Laboratory of Hydraulics and Mountain River Engineering College of Water Resource and HydropowerSichuan UniversityChengdu610065China research institute of Testing and Inspection Sinohydro Bureau 7 Co.Ltd.Chengdu610213China

The surrounding geological co.ditions and supporting structures of underground engineering are often updated during co.struction,and these updates require repeated numerical *** improve the numerical modeling efficiency of underground engineering,a modularized and parametric modeling cloud server is developed by using Python *** basic framework of the cloud server is as follows:input the modeling parameters into the web platform,implement Rhino software and FLAC3D software to model and run simulations in the cloud server,and return the simulation results to the web *** modeling program can automatically generate instructions that can run the modeling process in Rhino based on the input modeling *** main modules of the modeling program include modeling the 3D geological structures,the underground engineering structures,and the supporting structures as well as meshing the geometric *** particular,various cross-sections of underground caverns are crafted as parametricmodules in themodeling *** and parametric modeling program is used for a finite element simulation of the underground powerhouse of the Shuangjiangkou Hydropower *** co.plicatedmodel is rapidly generated for the simulation,and the simulation results are ***,this modularized and parametric modeling program is applicable for three-dimensional finite element simulations and analyses.

关键词： Underground engineering modularized and parametric modeling finite element method co.plex geological structure cloud modeling

Simulation of fire emergency evacuation in a large-passenger-flow subway station based on the on-site measured data of Shenzhen Metro

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Transportation Safety and Environment 2024年第1期6卷 47-55页

作者： Hua Chen Chenyang Zhang Jieyu Zhang Ya Shu Xinjian Qi Chaozhe Jiang Sichuan FAST Fire Safety Assessment co. LTD.Chengdu 610036SichuanChina School of Transportation and Logistics Southwest Jiaotong UniversityChengdu 611756SichuanChina Sichuan Fire research institute of MEM Chengdu 610036SichuanChina Shenzhen Metro Group co. LTD.Shenzhen 518026GuangdongChina

Because of its large capacity,high efficiency and energy savings,the subway has gradually beco.e the primary mode of transportation for citizens.A high density of passengers exists within a large-passenger-flow subway station,and the number of casualties and injuries during a fire emergency is *** this paper,Pathfinder software and on-site measured data of Pingzhou station in Shenzhen(China)were utilized to simulate a fire emergency evacuation in a large-passenger-flow subway *** Required Safe Egress Time(RSET),number of passengers and flow rates of stairs and escalators were analysed for three fire evacuation scenarios:train fire,platform fire and hall *** evacuation time of the train fire,which was 1173 s,was the longest,and 3621 occupants needed to evacuate when the train was fully *** co.ld not co.plete the evacuation within 6 mins in all three fire evacuation scenarios,which does not meet the current standard requirements and *** changing the number of passengers and the number of stairs for evacuation,the flow rate capacity and evacuation time were explored,which have reference values for safety management and emergency evacuation plan optimization during peak hours of subway operation.

关键词： fire emergency evacuation large-passenger-flow subway station on-site measured data Pathfinder

Exploring plant adaptation strategies to phosphorus limitation induced by nitrogen addition:foliar phosphorus allocation and root functional traits analysis in two dominant subalpine tree species

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Journal of Plant Eco.ogy 2024年第4期17卷 154-166页

作者： Yan Su Yongfeng Tang Yi Hu Meiyu Liu Xuyang Lu Baoli Duan institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China Sichuan Eco.ogical Environment co.struction Engineering Supervision co. Ltd.Chengdu 610084China

Plants adapt to the limitation of soil phosphorus(P)induced by nitrogen(N)deposition through a co.plex interaction of various root and leaf functional *** this study,a pot experiment was co.ducted to explore the effects of different levels of N addition(co.trol,low N[LN]:25 kg N ha^(-1) yr^(-1),high N[HN]:50 kg N ha^(-1) yr^(-1))on tree growth,leaf nutrient co.tent,foliar P fractions and root characteristics of two dominant tree species,the pioneer species Salix rehderiana Schneid and the climax species Abies fabri(Mast.)Craib,in a subalpine forest in southwestern *** results demonstrated that LN addition had a minimal impact on leaf N and P ***,HN addition significantly decreased the leaf P co.tent in both *** rehderiana exhibited more pronounced increases in specific root length and specific root area under P deficiency triggered by HN addition when co.pared with *** co.trast,*** showed weaker morphological responses to N addition but had a higher proportion of foliar P to metabolic P,as well as higher root exudates rate and root phosphatase activity in response to HN *** fabri employs a synergistic approach by allocating a greater amount of leaf P to metabolite P and extracting P from the soil through P-mobilizing exudates and root phosphatase activity,while *** exhibits higher flexibility in modifying its root morphology in response to P limitation induced by HN *** study provides insights into subalpine tree species adaptation to N-induced P limitation,emphasizing its significance for guiding forest management and co.servation in the co.text of global climate change.

关键词： N deposition root functional traits root morphology root exudation P-scavenging strategy

Hollow-structured all-silico. terahertz metasurface supporting quasi-bound states in the co.tinuum for refractive index based Auramine O co.centration sensing

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Photonics research 2024年第7期12卷 1574-1582页

作者： XIN TANG HAODUO JIA LANBIN LI MING LI DAI WU KUI ZHOU PENG LI WEIJUN WANG JITAO LI DINGYU YANG co.lege of Optoelectronic Engineering Chengdu University of Information TechnologyChengdu 610225China institute of Applied Electronics China Academy of Engineering PhysicsMianyang 621000China School of Precision Instruments and Opto-Electronics Engineering Tianjin UniversityTianjin 300072China Guizhou Zhenhua Fengguang Semico.ductor co. Ltd.Guiyang 550000China chengdu Huanyuxin Technology co. Ltd.Chengdu 610095China

Quasi-bound states in the co.tinuum (QBIC),with exceptionally high-Q factors and the local field enhancement effect,have found potential applications in matter *** the QBIC mechanism into terahertz(THz) metasurfaces can significantly enhance the interaction between incident THz waves and matter,providing a feasible platform for the detection of biochemical ***,most experimental studies on terahertz QBIC metasurfaces utilize metallic *** co.trast,research on terahertz all-dielectric QBIC metasurfaces generally remains at the simulation stage due to the high fabrication process requirements,and transitioning to the experimental stage still poses many *** this paper,a hollow-structured all-silico. metasurface supporting THz QBIC is *** resonance of THz QBIC is excited via a simple hollow structure and observed in *** and experimental results demonstrated that the designed THz QBIC metasurface can achieve sensing of Auramine ***,it is the first study,to our knowledge,to employ a metasurface to sense Auramine ***,the sensing performance maintains good stability under different humidity and temperature *** study provides new references and insights for the design and implementation of THz QBIC,and also opens a new pathway for the detection of Auramine O.

关键词： supporting co.tinuum refractive