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Adversarial attacks and defenses for digital communication signals identification

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Digital Communications and Networks 2024年第3期10卷 756-764页

作者： Qiao Tian Sicheng Zhang Shiwen Mao yun lin College of Computer Science and Technology Harbin Engineering UniversityHarbin150001China College of Information and Communication Engineering Harbin Engineering UniversityHarbin150000China Department of Electrical and Computer Engineering Auburn UniversityAuburnAL36849USA

As modern communication technology advances apace,the digital communication signals identification plays an important role in cognitive radio networks,the communication monitoring and management *** has become a promising solution to this problem due to its powerful modeling capability,which has become a consensus in academia and ***,because of the data-dependence and inexplicability of AI models and the openness of electromagnetic space,the physical layer digital communication signals identification model is threatened by adversarial *** examples pose a common threat to AI models,where well-designed and slight perturbations added to input data can cause wrong ***,the security of AI models for the digital communication signals identification is the premise of its efficient and credible *** this paper,we first launch adversarial attacks on the end-to-end AI model for automatic modulation classifi-cation,and then we explain and present three defense mechanisms based on the adversarial *** we present more detailed adversarial indicators to evaluate attack and defense ***,a demonstration verification system is developed to show that the adversarial attack is a real threat to the digital communication signals identification model,which should be paid more attention in future research.

关键词： Digital communication signals identification AI model Adversarial attacks Adversarial defenses Adversarial indicators

Thermal Decomposition and Oxidative Decomposition Mechanism of HfC-134a by Experimental and DfT Method

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Journal of Thermal Science 2024年第5期33卷 1990-2003页

作者： XU yunting ZHANG Kai DAI Xiaoye SHI lin Key Laboratory for Thermal Science and Power Engineering of Ministry of Education Department of Energy and Power EngineeringTsinghua UniversityBeijing 100084China

In response to the Kigali Amendment to the Montreal Protocol and global low-carbon emission environmental requirements,the phase-out and decomposition of numerous HfC refrigerants have become urgent,necessitating efficient and mild decomposition *** study investigates the thermal decomposition and oxidative thermal decomposition pathways of the typical hydrofluorocarbon refrigerant HfC-134a,employing a combination of experimental and quantum chemical DfT simulation *** chemical simulations reveal that the initial reaction bond cleavage serves as the rate-determining step during the thermal decomposition process,with the most easily detectable closed-shell products including Cf_(2)=CHf,Hf,CH_(3)f,CHf_(3),CH_(2)f_(2),and Cf_(4).Reactive oxygen species can significantly reduce the Gibbs free energy barrier for HfC-134a *** achieve efficient degradation of HfC-134a,appropriate catalysts should be developed and selected to increase the level of reactive oxygen species in the reaction *** studies further corroborate that HfC-134a may undergo degradation through distinct reaction pathways under varying temperature(240℃to360℃)and pressure(0.1 MPa to 4.5 MPa)conditions,in agreement with simulation predictions.

关键词： HfC-134a pyrolysis oxidative thermal decomposition DfT refrigerant

Non-convexity Pricing and Allocating Costs in Stochastic Electricity Markets

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CSEE Journal of Power and Energy Systems 2024年第4期10卷 1466-1477页

作者： Wei lin Zhifang yang Department of Electrical Engineering The Hong Kong Polytechnic UniversityHong Kong SARChina State Key Laboratory of Power Transmission Equipment&System Security and New Technology College of Electrical EngineeringChongqing UniversityChongqing 400030China

Stochastic electricity markets have drawn attention due to fast increase of renewable *** results in two issues:one is to reduce uplift payments arising from non-convexity under renewable uncertainties,and the other one is to allocate reserve costs based on renewable *** resolve the first issue,a convex hull pricing method for stochastic electricity markets is *** dual variables of system-wide constraints in a chance-constrained unit commitment model are shown to reduce expected uplift payments,together with developing a linear program to efficiently calculate such *** resolve the second issue,an allocation method is proposed to allocate reserve costs to each renewable power plant by explicitly investigating how renewable uncertainties of each renewable power plant affect reserve *** proposed methods are validated in a 24-period 3-unit test example and a 24-period 48-unit utility example.

关键词： Convex hull pricing cost allocation non-convexity renewable uncertainty stochastic electricity market

A Server Placement Algorithm for Reducing Risk and Improving Power Utilization in Data Centers

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Tsinghua Science and Technology 2024年第1期29卷 158-173页

作者： Rui Chen Huikang Huang Xiaoxuan Luo Weiwei lin School of Computer Science and Engineering South China University of TechnologyGuangzhou 510006China Peng Cheng Laboratory Shenzhen 518066China

As the power demand in data centers is increasing,the power capacity of the power supply system has become an essential resource to be *** many data centers use power oversubscription to make full use of the power capacity,there are unavoidable power supply risks associated with ***,how to improve the data center power capacity utilization while ensuring power supply security has become an important *** solve this problem,we first define it and propose a risk evaluation metric called Weighted Power Supply Risk(WPSRisk).Then,a method,named Hybrid Genetic Algorithm with Ant Colony System(HGAACS),is proposed to improve power capacity utilization and reduce power supply risks by optimizing the server placement in the power supply *** uses historical power data of each server to find a better placement solution by population *** possesses not only the remarkable local search ability of Ant Colony System(ACS),but also enhances the global search capability by incorporating genetic operators from Genetic Algorithm(GA).To verify the performance of HGAACS,we experimentally compare it with five other placement *** experimental results show that HGAACS can perform better than other algorithms in both improving power utilization and reducing the riskof powersupply system.

关键词： server placement power utilization power supply risk swarm intelligence algorithm

Method for triangular fuzzy multiple attribute decision making based on two-dimensional density operator method

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Journal of Systems Engineering and Electronics 2024年第1期35卷 178-185页

作者： lin youliang LI Wu LIU Gang HUANG Dong School of Economics and Management Hunan Institute of Science and TechnologyYueyang 414000China Hunan Vocational College for Nationalities Yueyang 414000China School of Information Science and Engineering Hunan Institute of Science and TechnologyYueyang 414000China

Aiming at the triangular fuzzy(Tf)multi-attribute decision making(MADM)problem with a preference for the distribution density of attribute(DDA),a decision making method with Tf number two-dimensional density(TfTD)operator is proposed based on the density operator theory for the decision maker(DM).firstly,a simple Tf vector clustering method is proposed,which considers the feature of Tf number and the geometric distance of ***,the least deviation sum of squares method is used in the program model to obtain the density weight ***,two TfTD operators are defined,and the MADM method based on the TfTD operator is ***,a numerical example is given to illustrate the superiority of this method,which can not only solve the Tf MADM problem with a preference for the DDA but also help the DM make an overall comparison.

关键词： fuzzy decision making clustering density operator multi-attribute decision making(MADM)

Effect of hot isostatic pressure on the microstructure and tensile properties of γ'-strengthened superalloy fabricated through induction-assisted directed energy deposition

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International Journal of Minerals,Metallurgy and Materials 2024年第5期31卷 1089-1097页

作者： Jianjun Xu Hanlin Ding Xin lin feng Liu Analytical&Testing Center Northwestern Polytechnical UniversityXi’an 710072China State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China

The microstructure characteristics and strengthening mechanism of Inconel738LC(IN-738LC) alloy prepared by using induction-assisted directed energy deposition(IDED) were elucidated through the investigation of samples subjected to IDED under 1050℃ preheating with and without hot isostatic pressing(HIP,1190℃,105 MPa,and 3 h).Results show that the as-deposited sample mainly consisted of epitaxial columnar crystals and inhomogeneously distributed γ’ phases in interdendritic and dendritic core *** HIP,grain morphology changed negligibly,whereas the size of the γ’ phase became increasingly *** further heat treatment(HT,1070℃,2 h + 845℃,24 h),the γ’ phase in the as-deposited and HIPed samples presented a bimodal size distribution,whereas that in the as-deposited sample showed a size that remained *** comparison of tensile properties revealed that the tensile strength and uniform elongation of the HIP + HTed sample increased by 5% and 46%,respectively,due to the synergistic deformation of bimodal γ’phases,especially large cubic γ’ ***,the relationship between phase transformations and plastic deformations in the IDEDed sample was discussed on the basis of generalized stability theory in terms of the trade-off between thermodynamics and kinetics.

关键词： directed energy deposition Ni-based superalloys high-temperature preheating hot isostatic pressing microstructure tensile properties

Grain refinement of 5A06 aluminum alloy welds caused by tungsten inert gas welding arc characteristics under Ar-He alternating gas supply conditions:a coupled method of water-cooled copper plate test/numerical simulation

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Journal of Iron and Steel Research International 2024年第3期31卷 767-777页

作者： Hong-bin Dai Jian Miao Jia-xin lin School of Materials Science and Engineering Harbin University of Science and TechnologyHarbin 150040HeilongjiangChina

The welding arc,as a carrier for the conversion of electrical energy to thermal energy,has a direct impact on the quality of welding by its properties and *** the tungsten inert gas(TIG)welding process under the condition of Ar-He alternating gas supply,the arc is alternately converted between Ar arc and He arc with an alternating gas supply cycle,which has obvious arc change *** fLUENT software was used to numerically simulate the characteristics of the TIG arc under the condition of alternating gas supply,and the arc temperature field,arc pressure,electric potential and current density distribution under the condition of alternating gas supply were *** with the real-time data of arc pressure measured by the water-cooled copper plate with holes,it is proved that the TIG arc has obvious dynamic characteristics under the condition of Ar-He alternating gas *** unique dynamic TIG arc acts on the 5A06 aluminum alloy weld,causing the molten pool to stir,resulting in uniform microstructure and grain refinement at the weld,and thereby improving the mechanical properties of the welded joint.

关键词： Alternating gas supply Grain refinement Numerical simulation Tungsten argon arc morphology Microstructure Mechanical property

Digital twin system framework and information model for industry chain based on industrial Internet

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frontiers of Information Technology & Electronic Engineering 2024年第7期25卷 951-967页

作者： Wenxuan WANG yongqin LIU Xudong CHAI lin ZHANG School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China Department of Control Science and Engineering Jilin UniversityChangchun 130012China CASICloud China Aerospace Science and Industry Corporation LimitedBeijing 100080China

The integration of industrial Internet,cloud computing,and big data technology is changing the business and management mode of the industry ***,the industry chain is characterized by a wide range of fields,complex environment,and many factors,which creates a challenge for efficient integration and leveraging of industrial big *** at the integration of physical space and virtual space of the current industry chain,we propose an industry chain digital twin(DT)system framework for the industrial *** addition,an industry chain information model based on a knowledge graph(KG)is proposed to integrate complex and heterogeneous industry chain data and extract industrial ***,the ontology of the industry chain is established,and an entity alignment method based on scientific and technological achievements is ***,the bidirectional encoder representations from Transformers(BERT)based multi-head selection model is proposed for joint entity–relation extraction of industry chain ***,a relation completion model based on a relational graph convolutional network(R-GCN)and a graph sample and aggregate network(GraphSAGE)is proposed which considers both semantic information and graph structure information of *** results show that the performances of the proposed joint entity–relation extraction model and relation completion model are significantly better than those of the ***,an industry chain information model is established based on the data of 18 industry chains in the field of basic machinery,which proves the feasibility of the proposed method.

关键词： Industry chain Digital twin Industrial Internet Knowledge graph Graph neural network

Transcriptomic analysis reveals the effects of maternal exposure to bisphenol Af on hypothalamic development in male neonatal mice

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Journal of Environmental Sciences 2024年第7期141卷 304-313页

作者： lin Lv yuanyuan Li Xuanyue Chen Zhanfen Qin State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China

fragmented data suggest that bisphenol Af(BPAf),a chemical widely used in a variety of products,might have potential impacts on the ***,we employed male neonatal mice following maternal exposure to explore the effects of low-dose BPAf on hypothalamic development by *** found that maternal exposure to approximately 50μg/(kg·day)BPAf from postanal day(PND)0 to PND 15 altered the hypothalamic transcriptome,primarily involving the pathways and genes associated with extracellular matrix(ECM)and intercellular adhesion,neuroendocrine regulation,and neurological *** RNA analysis confirmed the changes in the expression levels of concerned ***,we further revealed that low-dose BPAf posed a stimulatory impact on pro-opiomelanocortin(POMC)neurons in the arcuate nucleus of the hypothalamus and induced the browning of inguinal white adipose *** findings indicate that developmental exposure to low-dose BPAf could interfere with hypothalamic development and thereby lead to alterations in the ***,5000μg/(kg·day)BPAf caused slighter,non-significant or even inverse alterations than the low dose of 50μg/(kg·day),displaying a dose-independent *** observations suggest that the the dose-independent effects of BPAf might be associated with oxidative stress and inflammatory responses caused by the high ***,our study highlights a risk of low-dose BPAf to human neuroendocrine regulation and metabolism.

关键词： Bisphenol Af Hypothalamus Transcriptomic alteration Pro-opiomelanocortin(POMC)neurons White adipose tissue browning