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Threat Modeling and Application Research Based on Multi-Source Attack and Defense Knowledge

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Computers, Materials & Continua 2023年第10期77卷 349-377页

作者： Shuqin zhang Xinyu Su Peiyu Shi tianhui Du Yunfei Han School of Computer Science Zhongyuan University of TechnologyZhengzhouChina

Cyber Threat Intelligence(CTI)is a valuable resource for cybersecurity defense,but it also poses challenges due to its multi-source and heterogeneous nature.Security personnel may be unable to use CTI effectively to understand the condition and trend of a cyberattack and respond promptly.To address these challenges,we propose a novel approach that consists of three steps.First,we construct the attack and defense analysis of the cybersecurity ontology(ADACO)model by integrating multiple cybersecurity databases.Second,we develop the threat evolution prediction algorithm(TEPA),which can automatically detect threats at device nodes,correlate and map multisource threat information,and dynamically infer the threat evolution process.TEPA leverages knowledge graphs to represent comprehensive threat scenarios and achieves better performance in simulated experiments by combining structural and textual features of entities.Third,we design the intelligent defense decision algorithm(IDDA),which can provide intelligent recommendations for security personnel regarding the most suitable defense techniques.IDDA outperforms the baseline methods in the comparative experiment.

关键词： Multi-source data fusion threat modeling threat propagation path knowledge graph intelligent defense decision-making

Application Research on Two-Layer Threat Prediction Model Based on Event Graph

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Computers, Materials & Continua 2023年第12期77卷 3993-4023页

作者： Shuqin zhang Xinyu Su Yunfei Han tianhui Du Peiyu Shi School of Computer Science Zhongyuan University of TechnologyZhengzhouHEN037China

Advanced Persistent Threat(APT)is now the most common network assault.However,the existing threat analysis models cannot simultaneously predict the macro-development trend and micro-propagation path of APT attacks.They cannot provide rapid and accurate early warning and decision responses to the present system state because they are inadequate at deducing the risk evolution rules of network threats.To address the above problems,firstly,this paper constructs the multi-source threat element analysis ontology(MTEAO)by integrating multi-source network security knowledge bases.Subsequently,based on MTEAO,we propose a two-layer threat prediction model(TL-TPM)that combines the knowledge graph and the event graph.The macro-layer of TL-TPM is based on the knowledge graph to derive the propagation path of threats among devices and to correlate threat elements for threat warning and decision-making;The micro-layer ingeniously maps the attack graph onto the event graph and derives the evolution path of attack techniques based on the event graph to improve the explainability of the evolution of threat events.The experiment’s results demonstrate that TL-TPM can completely depict the threat development trend,and the early warning results are more precise and scientific,offering knowledge and guidance for active defense.

关键词： Knowledge graph multi-source data fusion network security threat modeling event graph absorbing Markov chain threat propagation path

Synthesis of polypeptide bearing 1,4-dithiane pendants for ROS-responsive drug release

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Chinese Chemical Letters 2020年第5期31卷 1129-1132页

作者： tianhui Zhang Jiuxu Yao Jiamei Tian Mingxiao Deng Xiuli Zhuang Chunsheng Xiao Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China University of Science and Technology of China.Hefei 230026 China Department of Chemistry.Northeast Normal University Changchun 130021China State Key Laboratory of Molecular Engineering of Polymers Fudan UniversityShanghai 200433China Jilin Biomedical Polymers Engineering Laboratory Changchun 130022China

Stimuli-re sponsive polypeptides have been intensively investigated fo r controlled drug release,owing to their favorable biocompatibility and biodegradability.In this work,we designed and synthesized a new kind of polypeptide bearing 1,4-dithiane pendants for reactive oxygen species(ROS)-responsive drug release.The polypeptide-based block copolymer was facilely synthesized by ring-opening polymerization(ROP)of 1,4-dithian-substituted L-glutamate N-carboxyanhydride(DTG-NCA)monomer using an amino-terminated poly(ethylene glycol)methyl ether(mPEG-NH2)as the macro molecular initiator.The resulta nt block copolyme r,mPEG-b-PDTG,could self-assemble into unifo rm micelles in aqueous medium owing to its amphiphilic structure.Then,the H2 O2-triggered oxidation behaviors of the mPEG-b-PDTG micelles were studied by dynamic light scattering(DLS),FT-IR and turbidimetric assay.It was revealed that the oxidation of thioether into sulfoxide in the side chains would result in disassembly of the micelles.Furthermore,the ROS-responsive drug release behavior of the mPEG-b-PDTG micelles was verified by using Nile Red as a model drug.MTT assay also proved that mPEG-b-PDTG was non-toxic in B16 F10 and L929 cells.Therefore,such a new class of oxidation-responsive polypeptide might provide a promising platform for ROS-responsive drug delivery.

关键词： Polypeptides ROS-responsive Self-assembly Thioether Drug release

Enhancement of solar-driven photocatalytic activity of oxygen vacancy-rich Bi/BiOBr/Sr_(2)LaF_(7)∶Yb^(3+),Er^(3+)composites through synergetic strategy of upconversion function and plasmonic effect

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Journal of Environmental Sciences 2022年第5期34卷 76-87页

作者： Yongjin Li Yingying zhang Jiajing Wang Youzhun Fan Taizhong Xiao Zhaoyi Yin tianhui Wang Jianbei Qiu Zhiguo Song School of Materials Science and Engineering Kunming University of Science and TechnologyKunming 650093China

For better use of solar energy,the development of efficient broadband photocatalyst has attracted extraordinary attention.In this study,a ternary composite consisting of Sr_(2)LaF_(7)∶Yb^(3+),Er^(3+)upconversion(UC)nanocrystals and Bi nanoparticles loaded BiOBr nanosheets with oxygen vacancies(OVs,SLFBB)was designed and synthesized by multi-step solvent-thermal method.Mechanisms of in-situ formation of Bi nanoparticles and OVs in BiOBr/Sr_(2)LaF_(7)∶Yb^(3+),Er^(3+)composites(SFLB)are clarified.The Bi metal and OVs enhanced the light-harvesting capacity in the region of visible-near-infrared(Vis-NIR),and promoted the separation of electron-hole(e-/h+)pairs.Furthermore,the surface plasmon resonance(SPR)effect of Bi metal can improve the energy transfer from Sr_(2)LaF_(7)∶Yb^(3+),Er^(3+)to BiOBr via nonradiative energy transfer process,resulting in enhancing the light utilization from up-converting NIR into Vis light.Due to the synergistic effects of UC function,SPR and OVs,the SFLBB exhibited obviously enhanced photocatalytic ability for the degradation of BPA with a rate of 8.9×10^(-3) min^(-1),which is about 2.78 times higher than 3.2×10^(-3) min^(-1) of BiOBr(BOB)under UV-Vis-NIR light irradiation.This work provides a novel strategy for the project of high-efficiency Bismuth-based broadband photocatalysts,which is helpful to fur-ther understand the mechanism of enhanced photocatalysis by UC function and plasmonic effect.

关键词： BiOBr/Sr_(2)LaF_(7)∶Yb^(3+),Er^(3+)composites In-situ generation Bi metal Oxygen vacancies Broadband photocatalysis

Experiment and Numerical Simulation on the Dynamic Response of Foam-Filled Tubes Under Lateral Blast Loading

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Acta Mechanica Solida Sinica 2021年第6期34卷 937-953页

作者： Zhifang Liu tianhui Zhang Shiqiang Li Jianyin Lei Zhihua Wang Institute of Applied Mechanics College of Mechanical and Vehicle EngineeringTaiyuan University of TechnologyTaiyuan030024China Shanxi Key Laboratory of Material Strength and Structural Impact Taiyuan University of TechnologyTaiyuan030024China

The dynamic response and energy absorption performance of foam-filled tubes under lateral external blast loading were investigated experimentally and numerically.A series of blast tests for the foam-filled tubes with different geometric parameters were carried out by the use of the ballistic pendulum system.Experimental results were compared with the numerical simulation results employing the software ABAQUS.The results showed that the finite element(FE)analysis was in good agreement with the experimental data.The effects of the diameter and wall thickness of the outer tube,the TNT explosive charge mass,and the standoff distance on the deformation modes,the blast resistance,and the energy absorption performance of the foam-filled tubes were investigated.Three deformation modes of the foam-filled tubes were observed under the lateral external blast loading,including local plastic deformation,large plastic deformation with an elliptic shape,and the tearing of the outer tube.The result revealed that the introduction of the foam core played a vital role in the deflection and energy absorption capacity of the structure.This study provided effective guidelines for designing foam-filled tubes with high energy absorption efficiency.

关键词： Foam-filled tubes Aluminum foam Lateral blast loading Numerical simulation

Impact of Household Endowments on Response Capacity of Farming Households to Natural Disasters

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International Journal of Disaster Risk Science 2012年第4期3卷 218-226页

作者： Haixia zhang tianhui Zhuang Weizhong Zeng College of Economics and Management Sichuan Agricultural University Chengdu 611130 China

This article investigates the impact of household endowments on household’s ability to cope with natural disaster risks and the determining factors of disaster coping capacity. We present results of a research based on household survey. The data were analyzed with an ordered Probit model regression. The project surveyed 923 rural households in 2009 and 2010 in 39 national-level poverty-stricken counties of Sichuan, Yunnan, and Guizhou Provinces and Chongqing Municipality. This research determined that the economic strength of households is the most important factor affecting their disaster coping capacity. The ability of farming households to cope with disasters is also significantly impacted by family members’ experiences and their economic context at the village level. Ethnic minority areas in southwestern China are the poorest in the country and are often the main disasteraffected areas. Since household endowments significantly affect the ability of farming households to cope with disasters, integration of disaster risk management and poverty reduction is a viable way of enhancing coping capacity of farming households to natural disasters.

关键词： disaster Impact Chongqing

A superconducting wireless energiser based on electromechanical energy conversion

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Superconductivity 2023年第3期7卷 53-64页

作者： Hongye zhang tianhui Yang Francesco Grilli Wenxin Li Paul M.Tuohy Ying Xin Department of Electrical and Electronic Engineering The University of ManchesterManchester M139PLUnited Kingdom School of Electrical and Information Engineering Tianjin UniversityTianjin 300072China Institute for Technical Physics Karlsruhe Institute of TechnologyKarlsruhe 76131Germany

A superconducting magnet(SM)can produce high magnetic fields up to a dozen times stronger than those generated by an electromagnet made of normal conductors or a permanent magnet(PM),and thus has attracted increasing research efforts in many domains including medical devices,large scientific equipment,transport,energy storage,power systems,and electric machines.Wireless energisers,e.g.,high temperature superconducting(HTS)flux pumps,can eliminate the thermal load from current leads and arc erosion of slip rings,and are thus considered a promising energisation tool for SMs.However,the time‐averaged DC output voltage in existing HTS flux pumps is generated by dynamic resistance:the dynamic loss is unavoidable,and the total AC loss will become significant at high frequencies.This study introduces a highly efficient superconducting wireless energizer(SWE)designed specifically for SMs.The SWE takes advantage of the inherent properties of a superconducting loop,including flux conservation and zero DC resistivity.Extensive theoretical analysis,numerical modelling exploiting the H‐ϕformulation,and experimental measurements were conducted to demonstrate the efficiency and efficacy of the novel SWE design.The electromechanical performance and loss characteristics of the SWE system have also been investigated.Compared to conventional HTS flux pumps,the proposed SWE has lower excitation loss,in the order of 10−1 mW,and thus can achieve a high system efficiency of no less than 95%.Furthermore,it has a simpler structure with higher reliability,considered ready for further industrial development.In addition to deepening the understating of the intricate electromechanical dynamics between magnetic dipoles and superconducting circuits,this article provides a novel wireless energisation technique for SMs and opens the way to step changes in future electric transport and energy sectors.

关键词： Wireless energisation Superconducting magnet High temperature superconductor Electromechanical energy conversion Electric transport

Genomic convergence underlying high-altitude adaptation in alpine plants

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Journal of Integrative Plant Biology 2023年第7期65卷 1620-1635页

作者： Xu zhang tianhui Kuang Wenlin Dong Zhihao Qian Huajie zhang Jacob BLandis Tao Feng Lijuan Li Yanxia Sun Jinling Huang Tao Deng Hengchang Wang Hang Sun CAS Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture The Chinese Academy of SciencesWuhan Botanical GardenWuhan 430074China Center of Conservation Biology Core Botanical GardensThe Chinese Academy of SciencesWuhan 430074China Yunnan International Joint Laboratory for Biodiversity of Central Asia Key Laboratory for Plant Diversity and Biogeography of East AsiaKunming Institute of BotanyThe Chinese Academy of SciencesKunming 650201China University of Chinese Academy of Sciences Beijing 100049China School of Integrative Plant Science Section of Plant Biology and the L.H.Bailey HortoriumCornell UniversityIthacaNew York 14850USA BTI Computational Biology Center Boyce Thompson InstituteIthacaNew York 14853USA State Key Laboratory of Crop Stress Adaptation and Improvement School of Life SciencesHenan UniversityKaifeng 475004China Department of Biology East Carolina UniversityGreenvilleNorth Carolina 27858USA

Evolutionary convergence is one of the most striking examples of adaptation driven by natural selection.However, genomic evidence for convergent adaptation to extreme environments remains scarce.Here, we assembled reference genomes of two alpine plants, Saussurea obvallata(Asteraceae)and Rheum alexandrae(Polygonaceae), with 37,938 and 61,463 annotated protein-coding genes. By integrating an additional five alpine genomes,we elucidated genomic convergence underlying high-altitude adaptation in alpine plants. Our results detected convergent contractions of diseaseresistance genes in alpine genomes, which might be an energy-saving strategy for surviving in hostile environments with only a few pathogens present.We identified signatures of positive selection on a set of genes involved in reproduction and respiration(e.g., MMD1, NBS1, and HPR), and revealed signatures of molecular convergence on genes involved in self-incompatibility, cell wall modification,DNA repair and stress resistance, which may underlie adaptation to extreme cold, high ultraviolet radiation and hypoxia environments. Incorporating transcriptomic data, we further demonstrated that genes associated with cuticular wax and flavonoid biosynthetic pathways exhibit higher expression levels in leafy bracts, shedding light on the genetic mechanisms of the adaptive “greenhouse” morphology. Our integrative data provide novel insights into convergent evolution at a high-taxonomic level,aiding in a deep understanding of genetic adaptation to complex environments.

关键词： adaptation alpine plants evolutionary rates genomic convergence “greenhouse”morphology high altitude

AIPerf: Automated Machine Learning as an AI-HPC Benchmark

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Big Data Mining and Analytics 2021年第3期4卷 208-220页

作者： Zhixiang Ren Yongheng Liu tianhui Shi Lei Xie Yue Zhou Jidong Zhai Youhui zhang Yunquan zhang Wenguang Chen Peng Cheng National Laboratory Shenzhen 518000China Department of Computer Science and Technology Tsinghua UniversityBeijing 100084China Institute of Computing Technology Chinese Academy of SciencesBeijing 100086China

The plethora of complex Artificial Intelligence(AI)algorithms and available High-Performance Computing(HPC)power stimulates the expeditious development of AI components with heterogeneous designs.Consequently,the need for cross-stack performance benchmarking of AI-HPC systems has rapidly emerged.In particular,the de facto HPC benchmark,LINPACK,cannot reflect the AI computing power and input/output performance without a representative workload.Current popular AI benchmarks,such as MLPerf,have a fixed problem size and therefore limited scalability.To address these issues,we propose an end-to-end benchmark suite utilizing automated machine learning,which not only represents real AI scenarios,but also is auto-adaptively scalable to various scales of machines.We implement the algorithms in a highly parallel and flexible way to ensure the efficiency and optimization potential on diverse systems with customizable configurations.We utilize Operations Per Second(OPS),which is measured in an analytical and systematic approach,as a major metric to quantify the AI performance.We perform evaluations on various systems to ensure the benchmark’s stability and scalability,from 4 nodes with 32 NVIDIA Tesla T4(56.1 Tera-OPS measured)up to 512 nodes with 4096 Huawei Ascend 910(194.53 Peta-OPS measured),and the results show near-linear weak scalability.With a flexible workload and single metric,AIPerf can easily scale on and rank AI-HPC,providing a powerful benchmark suite for the coming supercomputing era.

关键词： High-Performance Computing(HPC) Artificial Intelligence(AI) automated machine learning