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Controlling update distance and enhancing fair trainable prototypes in federated learning under data and model heterogeneity
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作者 Kangning Yin Zhen Ding +1 位作者 Xinhui Ji Zhiguo Wang 《Defence Technology(防务技术)》 2025年第5期15-31,共17页
Heterogeneous federated learning(HtFL)has gained significant attention due to its ability to accommodate diverse models and data from distributed combat units.The prototype-based HtFL methods were proposed to reduce t... Heterogeneous federated learning(HtFL)has gained significant attention due to its ability to accommodate diverse models and data from distributed combat units.The prototype-based HtFL methods were proposed to reduce the high communication cost of transmitting model parameters.These methods allow for the sharing of only class representatives between heterogeneous clients while maintaining privacy.However,existing prototype learning approaches fail to take the data distribution of clients into consideration,which results in suboptimal global prototype learning and insufficient client model personalization capabilities.To address these issues,we propose a fair trainable prototype federated learning(FedFTP)algorithm,which employs a fair sampling training prototype(FSTP)mechanism and a hyperbolic space constraints(HSC)mechanism to enhance the fairness and effectiveness of prototype learning on the server in heterogeneous environments.Furthermore,a local prototype stable update(LPSU)mechanism is proposed as a means of maintaining personalization while promoting global consistency,based on contrastive learning.Comprehensive experimental results demonstrate that FedFTP achieves state-of-the-art performance in HtFL scenarios. 展开更多
关键词 heterogeneous federated learning Model heterogeneity Data heterogeneity Contrastive learning
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异构CPU-GPU系统机密计算综述
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作者 郝萌 李佳勇 +1 位作者 杨洪伟 张伟哲 《信息网络安全》 北大核心 2025年第11期1658-1672,共15页
随着人工智能等数据密集型应用的普及,以CPU与GPU为核心的异构计算系统已成为关键基础设施。然而,在云和边缘等非可信环境中,敏感数据在处理阶段面临着严峻的安全威胁,传统加密方法对此无能为力。机密计算利用硬件可信执行环境(TEE)为... 随着人工智能等数据密集型应用的普及,以CPU与GPU为核心的异构计算系统已成为关键基础设施。然而,在云和边缘等非可信环境中,敏感数据在处理阶段面临着严峻的安全威胁,传统加密方法对此无能为力。机密计算利用硬件可信执行环境(TEE)为保护使用中的数据提供了有效方案,但现有技术主要集中在CPU端。将TEE安全边界无缝扩展至计算引擎核心GPU,已成为当前学术界与工业界关注的焦点。文章对CPU-GPU异构系统中的机密计算技术进行系统性综述。首先,文章回顾了机密计算的基本概念并剖析了针对GPU的典型攻击向量。然后,对现有GPU机密计算方案进行分类,涵盖硬件辅助、软硬件协同及纯软件实现等技术范式。最后,文章总结了该领域面临的关键挑战,并展望了未来研究方向。 展开更多
关键词 机密计算 可信执行环境 异构计算 GPU
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HETEROGENEITY OF THE LITHOSPHERE IN TIBETAN PLATEAU ON THE CONSTRAINTS OF MAGMATISM 被引量:1
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作者 Mo Xuanxue,Guo Tieying, Zhao Zhidan, Luo Zhaohua 《地学前缘》 EI CAS CSCD 2000年第S1期322-322,共1页
Many evidences including those from magmatism and igneous rocks strongly support the heterogeneity of lithosphere in Tibetan plateau.By estimation, volcanic and plutonic rocks occupy an area of 300000km\+2, equaling t... Many evidences including those from magmatism and igneous rocks strongly support the heterogeneity of lithosphere in Tibetan plateau.By estimation, volcanic and plutonic rocks occupy an area of 300000km\+2, equaling to 10% of total area of the Tibetan Plateau. Temporal and spatial distribution of igneous rocks in the Tibetan Plateau is very inhomogeneous (Mo et al., 1998). Temporarily, most of plutonic and volcanic rocks, which occurred in 60% of total area of igneous rocks in the plateau, formed in the period of 65~45Ma. Spatially, 80% of igneous rocks in the plateau concentrated in the Gangdise—Nyainqentanglha region formed a huge complex granite\|volcanic belt. Petrotectonic assemblage and type of igneous rocks also vary from district to district. While Himalayas (especially High\|Himalayan region) were characterized by well development of muscovite\|bearing granites with no high\|potassium volcanic rocks and other volcanic contemporaries, North Tibet (Qiangtang region) by highly potassic volcanic rock series without muscovite\|bearing granites. Besides wide\|spreading calc\|alkaline igneous rocks, however, both highly potassic volcanic rocks and muscovite\|bearing granites developed in the central portion of Gangdise\|Nyainqentanglha region. It was lack of igneous activities in the Pamirs. Mantle\|derived nodules and their hosted rocks have been found only on northern and eastern margins of the plateau so far. All mentioned above, combined with other evidences from geophysics, geochemistry and structural geology, give us a hint to understand the heterogeneity of the lithosphere in its structure, thermal state and evolution processes underneath Tibetan plateau. 展开更多
关键词 heterogeneity LITHOSPHERE TIBET PLATEAU
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Effect of heterogeneity on mechanical and acoustic emission characteristics of rock specimen 被引量:8
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作者 李术才 李国莹 《Journal of Central South University》 SCIE EI CAS 2010年第5期1119-1124,共6页
The influence of heterogeneity on mechanical and acoustic emission characteristics of rock specimen under uniaxial compress was studied with numerical simulation methods.Weibull distribution function was adopted to de... The influence of heterogeneity on mechanical and acoustic emission characteristics of rock specimen under uniaxial compress was studied with numerical simulation methods.Weibull distribution function was adopted to describe the mesoscopic heterogeneity of rocks.The failure process of heterogeneous rock specimen under uniaxial loading was simulated using FLAC 3D software.Five schemes were adopted to investigate the influence of heterogeneity.The results demonstrate that as the homogeneity increases,the peak strength and brittleness of rocks increase,and the macro elastic modulus improves as well.Heterogeneity has great influence on macro elastic modulus and strength when the homogeneity coefficient is less than 20.0.The volume expansion is not so obvious when the homogeneity increases.As the homogeneity coefficient increases the acoustic emissions modes change from swarm shock to main shock.When the homogeneity coefficient is high,the cumulative acoustic emission events-axial strain curve is gentle before the rock failure.The numerical results agree with the previously numerical results and earlier experimental measurements. 展开更多
关键词 heterogeneity acoustic emission strain softening numerical simulation uniaxial compression elastic modulus
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Numerical simulation on effect of heterogeneity on modeΙfracture characteristics of rock 被引量:6
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作者 WANG Jin-tao ZUO Jian-ping 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第10期3063-3077,共15页
Rock is more sensitive to tensile loading than compressive loading,since the tensile strength of rock is much lower than compressive strength.The fracture characteristics of rock in the tensile state are of great sign... Rock is more sensitive to tensile loading than compressive loading,since the tensile strength of rock is much lower than compressive strength.The fracture characteristics of rock in the tensile state are of great significance to the understanding of rock failure mechanisms.To this end,we have conducted numerical simulation researches on modeⅠcracking process of rock with varying homogeneity,using the Realistic Failure Process Analysis program.With the increase of homogeneity,cracks are concentrating to the ligament area with a decreasing number of crack bifurcations,and the main crack path is becoming smooth.Crack behaviors and mechanical properties are influenced significantly when the homogeneity index is in the range of 1.5 to 5.When the homogeneity index is greater than 30,they are not affected by rock homogeneity and the rock can be considered as essentially homogeneous.It is considered that the global and local strengths are affected by the distribution of rock mechanical properties at mesoscale,which influence the crack behaviors and mechanical characteristics. 展开更多
关键词 rock heterogeneity crack evolution subcritical crack growth fracture mechanism
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Effects of porosity heterogeneity on chemical dissolution-front instability in fluid-saturated rocks 被引量:4
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作者 ZHAO Chong-bin Peter SCHAUBS Bruce HOBBS 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第3期720-725,共6页
Homogeneity and heterogeneity are two totally different concepts in nature.At the particle length scale,rocks exhibit strong heterogeneity in their constituents and porosities.When the heterogeneity of porosity obeys ... Homogeneity and heterogeneity are two totally different concepts in nature.At the particle length scale,rocks exhibit strong heterogeneity in their constituents and porosities.When the heterogeneity of porosity obeys the random uniform distribution,both the mean value and the variance of porosities in the heterogeneous porosity field can be used to reflect the overall heterogeneous characteristics of the porosity field.The main purpose of this work is to investigate the effects of porosity heterogeneity on chemical dissolution front instability in fluid-saturated rocks by the computational simulation method.The related computational simulation results have demonstrated that:1) since the propagation speed of a chemical dissolution front is inversely proportional to the difference between the final porosity and the mean value of porosities in the initial porosity field,an increase in the extent of the porosity heterogeneity can cause an increase in the mean value of porosities in the initial porosity field and an increase in the propagation speed of the chemical dissolution front.2) An increase in the variance of porosities in the initial porosity field can cause an increase in the instability probability of the chemical dissolution front in the fluid-saturated rock.3) The greater the mean value of porosities in the initial porosity field,the quicker the irregular morphology of the chemical dissolution front changes in the supercritical chemical dissolution systems.This means that the irregular morphology of a chemical dissolution front grows quicker in a porosity field of heterogeneity than it does in that of homogeneity when the chemical dissolution system is at a supercritical stage. 展开更多
关键词 porosity heterogeneity chemical dissolution front instability computational simulation porous rocks
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Effects of microstructural heterogeneity on fatigue properties of cast aluminum alloys 被引量:6
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作者 JIAO Yi-nan ZHANG Yi-fan +6 位作者 MA Shi-qing SANG De-li ZHANG Yang ZHAO Jin-jin WU Sheng-chuan LIU Yong-qiang YANG Shao-pu 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第3期674-697,共24页
Cast Al alloys are widely employed for engine components,structural parts,gear box,chassis,etc.and subjected to mechanical cyclic load during operation.The accurate fatigue life prediction of these alloys is essential... Cast Al alloys are widely employed for engine components,structural parts,gear box,chassis,etc.and subjected to mechanical cyclic load during operation.The accurate fatigue life prediction of these alloys is essential for normal operation as fatigue cracks initiated during operation induce the lubrication oil leak and serious safety hazard.Microstructural heterogeneity,including shrinkage/gaspores and secondary phase particles,is the most detrimental factor that affects fatigue life of cast Al alloys.The approximate fatigue life cycles could be estimated based on the size distribution and locations of shrinkage pores/defects.The relationship between crack population and stress was reported by statistical distributions and the cumulative probability for cast Al alloys fail at a certain stress could be predicted by combination of Paris law and pore size distribution.Pore depth was found to dominate the stress field around the pore on the surface and the maximum stress increases sharply when the pore intercepted with the surface at its top.The microstructure of cast Al alloys usually is composed of primary Al dendrites,eutectic silicon,Fe-rich particles and other intermetallic particles are dependent upon alloy composition and heat treatment.The coalescence of microcracks initiated from the fractured secondary phases was clearly found and can accelerate the initiation and propagation of the fatigue cracks.A link between defect features and the fatigue strength needs to be established through a good understanding of the fatigue damage mechanisms associated with the microstructural features under specific loading conditions.This paper reviews the influences of shrinkage/gaspores and secondary phase particles,formed during casting process,on the fatigue life of Al-Si-Mg cast Al alloys. 展开更多
关键词 cast aluminum alloys FATIGUE microstructural heterogeneous shrinkage/gas pore secondary phase particles
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基于CPU-GPU的超音速流场N-S方程数值模拟
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作者 卢志伟 张皓茹 +3 位作者 刘锡尧 王亚东 张卓凯 张君安 《中国机械工程》 北大核心 2025年第9期1942-1950,共9页
为深入分析超音速流场的特性并提高数值计算效率,设计了一种高效的加速算法。该算法充分利用中央处理器-图形处理器(CPU-GPU)异构并行模式,通过异步流方式实现数据传输及处理,显著加速了超音速流场数值模拟的计算过程。结果表明:GPU并... 为深入分析超音速流场的特性并提高数值计算效率,设计了一种高效的加速算法。该算法充分利用中央处理器-图形处理器(CPU-GPU)异构并行模式,通过异步流方式实现数据传输及处理,显著加速了超音速流场数值模拟的计算过程。结果表明:GPU并行计算速度明显高于CPU串行计算速度,其加速比随流场网格规模的增大而明显提高。GPU并行计算可以有效提高超音速流场的计算速度,为超音速飞行器的设计、优化、性能评估及其研发提供一种强有力的并行计算方法。 展开更多
关键词 超音速流场 中央处理器-图形处理器 异构计算 有限差分
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Geological Causes of Permeability Heterogeneity in a Fractured Sandstone-Mudstone Rock Mass in the Xiaolangdi Dam Site,Central China
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作者 Xiaowei Jiang~1,Wan Li~1,Xusheng Wang~1,Aibin Kang~1,Jun Huang~(2,3),Guoxing Huang~1 1.School of Water Resources & Environment,China University of Geosciences(Beijing),Beijing 100083,China. 2.Research Center of Tunneling and Underground Engineering,Beijing Jiaotong University,Beijing 100044,China 3.China Highway Planning and Design Institute(HPDI) Consultants,INC,Beijing 100010,China 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期16-17,共2页
Heterogeneity of permeability in fractured media is a hot research topic in hydrogeology and numerous approaches had been proposed to characterize heterogeneity in the past several decades.However。
关键词 fractured media PERMEABILITY heterogeneity DECLUSTERING distribution of mudston
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Mechanical heterogeneity characterization of coal materials based on nano-indentation experiments
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作者 ZHANG Qi LI Xiang-chun +3 位作者 LI Biao MENG Jun-qing NIE Bai-sheng LU Wei-dong 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第9期3142-3155,共14页
To investigate the complex macro-mechanical properties of coal from a micro-mechanical perspective,we have conducted a series of micro-mechanical experiments on coal using a nano-indentation instrument.These experimen... To investigate the complex macro-mechanical properties of coal from a micro-mechanical perspective,we have conducted a series of micro-mechanical experiments on coal using a nano-indentation instrument.These experiments were conducted under both dynamic and static loading conditions,allowing us to gather the micro-mechanical parameters of coal for further analysis of its micro-mechanical heterogeneity using the box counting statistical method and the Weibull model.The research findings indicate that the load–displacement curves of the coal mass under the two different loading modes exhibit noticeable discreteness.This can be attributed to the stress concentration phenomenon caused by variations in the mechanical properties of the micro-units during the loading process of the coal mass.Consequently,there are significant fluctuations in the micro-mechanical parameters of the coal mass.Moreover,the mechanical heterogeneity of the coal at the nanoscale was confirmed based on the calculation results of the standard deviation coefficient and Weibull modulus of the coal body’s micromechanical parameters.These results reveal the influence of microstructural defects and minerals on the uniformity of the stress field distribution within the loaded coal body,as well as on the ductility characteristics of the micro-defect structure.Furthermore,there is a pronounced heterogeneity in the micromechanical parameters.Furthermore,we have established a relationship between the macro and micro elastic modulus of coal by applying the Mori-Tanaka homogenization method.This relationship holds great significance for revealing the micro-mechanical failure mechanism of coal. 展开更多
关键词 nano-indentation experiment MICROMECHANICS heterogeneity characterization COAL
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Hydraulic tomography to characterize ,heterogeneity of unconfined aquifers 被引量:2
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作者 Zhu Jun-Feng Tian-Chyi +1 位作者 Jim Yeh Mao De-Qiang 《南京大学学报(自然科学版)》 CAS CSCD 北大核心 2011年第3期252-264,共13页
关键词 英文摘要 内容介绍 编辑工作 期刊
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Metabolic heterogeneity of gastric cancer cell lines
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作者 Xia-xia FAN Ying-li ZHU +5 位作者 Bei-bei SHAO Lu-lu LI Ya-fei LI Ao JIA Ai-feng WANG Yong-cheng MA 《中国药理学与毒理学杂志》 CAS CSCD 北大核心 2018年第4期278-279,共2页
OBJECTIVE Gastric cancer is one of the most common malignant tumors,and the incidence rate is the highest in all kinds of tumors in China.However,it remains unclear that how signifi.cantly gastric cells are dependent ... OBJECTIVE Gastric cancer is one of the most common malignant tumors,and the incidence rate is the highest in all kinds of tumors in China.However,it remains unclear that how signifi.cantly gastric cells are dependent on glycolysis,and which type of gastric cells are sensitive to glycolysis inhibition.In this study,several kind of gastric cancer cell lines were used as the research object,and the metabolic characteristics of different cell lines were systematically analyzed to provide theoretical support for the accurate treatment of gastric cancer.METHODS We examined the energy metabolism of four gastric cancer cell lines(MGC-803,SGC-7901,HGC-27 and BGC-823) by using glycolysis inhibitor,2-deoxy-D-glucose(2-DG) and inhibitor of oxidative phosphorylation,oligomycin.Oxygen consumption rates(OCR) and L-lactate were also measured with an XF96 Analyzer(Seahorse Biosciences) to deter.mine the significance of metabolism of oxidative phosphorylation and aerobic glycolysisin gastric cells.In addition,western blot was used to detect the contribution of AMP-activated protein kinase(AMPK),and anti-apoptotic proteins(Bcl-2 and survivin) to clarify the mechanism of death or survival of gastric cancer cells treated by 2-DG or oligomycin.RESULTS In this study,it was shown that the growth of gastric cell lines were suppressed by 2-DG.However,the sensitivity to 2-DG was quite different among cell lines:IC 50 of 2-DG was from 3.28 mmol·L^(-1)(MGC-803) to 15.57 mmol·L^(-1)(BGC-823).MGC-803 was relatively sensitive to 2-DG(IC 50:3.28 mmol·L^(-1)),consumed more glucose and produced more lactate(waste product of glycolysis) than the three other cell lines.Consequently,MGC-803 could be more dependent on glycolysis than other cell lines,which was further confirmed by the fact that glucose(+) FCS(-) medium showed more growth and survival than glucose(-) FCS(+) medium.Alternatively,BGC-823,most resistant to 2-DG(IC50:15.57 mmol · L-1),was most sensitive to oligomycin,and showed more growth and survival in glucose(-) FCS(+) medium than in glucose(+) FCS(-) medium.Thus,we had reasons to think BGC-823 cells depended on oxidative phosphorylation for energy production.In BGC-823,AMPK,which is activated when ATP becomes limiting,was rapidly phosphorylated by 2-DG,and expression of Bcl-2 was augmented,which might result in resistance to 2-DG.Interestingly,AMPK phosphorylation and augmentation of Bcl-2 expression by 2-DG were not observed in MGC-803,which is 2-DG sensitive.CONCLUSION There is a large metabolic difference between gastric cancer cell lines,which will facilitate the future gastric cancer therapy by targeting metabolic pathways. 展开更多
关键词 胃癌 恶性肿瘤 治疗方法 临床分析
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基于CPU-GPU协同的迭代物理光学并行算法研究
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作者 曹倩 周远国 +1 位作者 任强 王焱 《电波科学学报》 北大核心 2025年第3期427-438,共12页
随着雷达技术与无人驾驶的结合,电磁仿真在无人驾驶领域得到了广泛应用。当利用迭代物理光学(iterative physical optics,IPO)法求解电大散射体雷达散射截面(radar cross section,RCS)时,未知量数目比较大,导致占用内存和计算耗时非常... 随着雷达技术与无人驾驶的结合,电磁仿真在无人驾驶领域得到了广泛应用。当利用迭代物理光学(iterative physical optics,IPO)法求解电大散射体雷达散射截面(radar cross section,RCS)时,未知量数目比较大,导致占用内存和计算耗时非常大。为解决该问题,本文引入参数空间技术优化IPO算法,提高了电大尺寸RCS的计算效率,并引入计算统一设备架构(compute unified device architecture,CUDA)技术,在中央处理器(central processing unit,CPU)与图形处理器(graphics processing unit,GPU)协同平台上实现了电大尺寸目标RCS的并行计算。与商业软件FEKO比对,在NVIDIA GeForce RTX 3050显卡上获得了224.35的加速比。实例结果展示了基于CPU-GPU协同的IPO算法并行计算的可行性与高效性,可以用来解决目前只能在高性能计算机或计算机集群上解决的电大尺寸目标散射问题。 展开更多
关键词 迭代物理光学法(IPO) 参数空间技术 cpu-gpu协同 并行加速 雷达散射截面(RCS)
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A hybrid genetic algorithm to the program optimization model based on a heterogeneous network
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作者 CHEN Hang DOU Yajie +3 位作者 CHEN Ziyi JIA Qingyang ZHU Chen CHEN Haoxuan 《Journal of Systems Engineering and Electronics》 2025年第4期994-1005,共12页
Project construction and development are an impor-tant part of future army designs.In today’s world,intelligent war-fare and joint operations have become the dominant develop-ments in warfare,so the construction and ... Project construction and development are an impor-tant part of future army designs.In today’s world,intelligent war-fare and joint operations have become the dominant develop-ments in warfare,so the construction and development of the army need top-down,top-level design,and comprehensive plan-ning.The traditional project development model is no longer suf-ficient to meet the army’s complex capability requirements.Projects in various fields need to be developed and coordinated to form a joint force and improve the army’s combat effective-ness.At the same time,when a program consists of large-scale project data,the effectiveness of the traditional,precise mathe-matical planning method is greatly reduced because it is time-consuming,costly,and impractical.To solve above problems,this paper proposes a multi-stage program optimization model based on a heterogeneous network and hybrid genetic algo-rithm and verifies the effectiveness and feasibility of the model and algorithm through an example.The results show that the hybrid algorithm proposed in this paper is better than the exist-ing meta-heuristic algorithm. 展开更多
关键词 program optimization heterogeneous network genetic algorithm portfolio selection.
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Functional cartography of heterogeneous combat networks using operational chain-based label propagation algorithm
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作者 CHEN Kebin JIANG Xuping +2 位作者 ZENG Guangjun YANG Wenjing ZHENG Xue 《Journal of Systems Engineering and Electronics》 2025年第5期1202-1215,共14页
To extract and display the significant information of combat systems,this paper introduces the methodology of functional cartography into combat networks and proposes an integrated framework named“functional cartogra... To extract and display the significant information of combat systems,this paper introduces the methodology of functional cartography into combat networks and proposes an integrated framework named“functional cartography of heterogeneous combat networks based on the operational chain”(FCBOC).In this framework,a functional module detection algorithm named operational chain-based label propagation algorithm(OCLPA),which considers the cooperation and interactions among combat entities and can thus naturally tackle network heterogeneity,is proposed to identify the functional modules of the network.Then,the nodes and their modules are classified into different roles according to their properties.A case study shows that FCBOC can provide a simplified description of disorderly information of combat networks and enable us to identify their functional and structural network characteristics.The results provide useful information to help commanders make precise and accurate decisions regarding the protection,disintegration or optimization of combat networks.Three algorithms are also compared with OCLPA to show that FCBOC can most effectively find functional modules with practical meaning. 展开更多
关键词 functional cartography heterogeneous combat network functional module label propagation algorithm operational chain
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Disintegration of heterogeneous combat network based on double deep Q-learning
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作者 CHEN Wenhao CHEN Gang +1 位作者 LI Jichao JIANG Jiang 《Journal of Systems Engineering and Electronics》 2025年第5期1235-1246,共12页
The rapid development of military technology has prompted different types of equipment to break the limits of operational domains and emerged through complex interactions to form a vast combat system of systems(CSoS),... The rapid development of military technology has prompted different types of equipment to break the limits of operational domains and emerged through complex interactions to form a vast combat system of systems(CSoS),which can be abstracted as a heterogeneous combat network(HCN).It is of great military significance to study the disintegration strategy of combat networks to achieve the breakdown of the enemy’s CSoS.To this end,this paper proposes an integrated framework called HCN disintegration based on double deep Q-learning(HCN-DDQL).Firstly,the enemy’s CSoS is abstracted as an HCN,and an evaluation index based on the capability and attack costs of nodes is proposed.Meanwhile,a mathematical optimization model for HCN disintegration is established.Secondly,the learning environment and double deep Q-network model of HCN-DDQL are established to train the HCN’s disintegration strategy.Then,based on the learned HCN-DDQL model,an algorithm for calculating the HCN’s optimal disintegration strategy under different states is proposed.Finally,a case study is used to demonstrate the reliability and effectiveness of HCNDDQL,and the results demonstrate that HCN-DDQL can disintegrate HCNs more effectively than baseline methods. 展开更多
关键词 heterogeneous combat network(HCN) combat system of systems(CSoS) network disintegration reinforcement learning
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考虑参数不确定性的地下水数值模型误差补偿校正方法
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作者 胡立堂 甘霖 +3 位作者 孙建冲 刘宏博 田蕾 沈琦 《地学前缘》 北大核心 2026年第1期432-443,共12页
模型结构和参数取值的不确定性是制约地下水模型仿真精度和实现高精度管理应用的关键因素。针对这一问题,本文提出了一种基于观测井观测数据的地下水水头模拟误差补偿校正方法。该方法首先对观测井的模拟水位进行误差校正,再利用反距离... 模型结构和参数取值的不确定性是制约地下水模型仿真精度和实现高精度管理应用的关键因素。针对这一问题,本文提出了一种基于观测井观测数据的地下水水头模拟误差补偿校正方法。该方法首先对观测井的模拟水位进行误差校正,再利用反距离插值技术估计误差的空间分布,最后将误差补偿应用于模型中其他网格点,实现整体模拟精度的提升。研究基于自主研发的地下水流数值模拟软件,设计了三种真实非均质介质、定流量和变流量抽注水、不同开采井和观测井数量组合的多种模拟情景,系统评估了均质水文地质模型误差补偿校正方法对水头模拟的效果。结果表明,误差补偿校正后的观测井水头模拟精度显著提高,且精度提升程度与渗透系数的平均值成反比、与其方差成正比。在多井抽水注水及强非均质变流量条件下,均方根误差由1.5 m降至0.25 m。通过对多种校正点数量情景的比较分析发现,所提出的方法在校正点位置的模拟效果显著提升,但对空间范围内地下水水头的整体模拟效果提升较为有限。研究方法可提升已识别地下水数值模型的模拟精度,具有较好的推广应用价值。 展开更多
关键词 地下水数值模型 非均质 误差校正补偿 参数不确定性 模型仿真性
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川滇地区人工智能地震预测模型应用
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作者 孟令媛 胡峰 +7 位作者 臧阳 司旭 闫伟 田雷 赵小艳 张致伟 韩颜颜 王月 《地震研究》 北大核心 2026年第1期43-50,共8页
针对中国地震科学实验场的科学目标和主要科学问题,基于川滇地区地震目录和地球物理观测数据,在对川滇地区进行区域划分并建立图神经网络的基础上,构建了川滇地区地震预测模型。该模型综合考虑约3万条地震目录数据、基于地震目录的3种... 针对中国地震科学实验场的科学目标和主要科学问题,基于川滇地区地震目录和地球物理观测数据,在对川滇地区进行区域划分并建立图神经网络的基础上,构建了川滇地区地震预测模型。该模型综合考虑约3万条地震目录数据、基于地震目录的3种地震活动性参数,以及116台项地球物理观测数据,通过将传统经验预测指标方法与人工智能技术结合,给出了适用于川滇地区的多源异构数据图神经网络地震预测模型,实现了川滇地区不同数据源下短期与中期地震预测功能。模型应用结果显示,在CD2、CD8和CD10区域月尺度预测效果较好,年尺度无震预测有一定对应效果。 展开更多
关键词 中国地震科学实验场 多源异构数据 图神经网络 地震预测模型 川滇地区
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CPU-GPU系统中基于剖分的全局性能优化方法 被引量:10
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作者 张保 董小社 +3 位作者 白秀秀 曹海军 刘超 梅一多 《西安交通大学学报》 EI CAS CSCD 北大核心 2012年第2期17-23,共7页
针对将应用移植到CPU-GPU异构并行系统上时优化策略各自分散、没有一个全局的指导思想的问题,提出了一种基于剖分的全局性能优化方法.该方法由优化策略库、剖分工具库和策略配置模块组成.优化策略库将应用移植到异构并行系统上的性能优... 针对将应用移植到CPU-GPU异构并行系统上时优化策略各自分散、没有一个全局的指导思想的问题,提出了一种基于剖分的全局性能优化方法.该方法由优化策略库、剖分工具库和策略配置模块组成.优化策略库将应用移植到异构并行系统上的性能优化过程划分为访存级、内核加速级和数据划分级3级优化;针对3级优化剖分工具库提供了3级剖分机制,通过运行时的剖分技术获取剖分信息;策略配置模块根据所获取的信息指导用户在每级优化中选择合适的优化策略.实验证明,基于剖分的全局性能优化方法可以明确地指导将应用移植到CPU-GPU异构并行系统上的全局优化过程,利用该优化方法后,以矩阵相乘和傅里叶变换为例的应用性能提升明显,最终性能相对于访存级优化最高可提高30%左右. 展开更多
关键词 cpu-gpu异构并行系统 全局优化 3级优化 3级剖分
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基于CPU-GPU异构的电力系统静态电压稳定域边界并行计算方法 被引量:10
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作者 李雪 张琳玮 +2 位作者 姜涛 陈厚合 李国庆 《电工技术学报》 EI CSCD 北大核心 2021年第19期4070-4084,共15页
为提升区域互联电力系统静态电压稳定域边界(SVSRB)的构建效率,该文以直接法为基础,提出一种基于CPU-GPU异构的静态电压稳定域边界并行计算方法。该方法首先依据SVSRB拓扑特性,基于边界追踪算法实现直接法求解鞍结分岔(SNB)点时初值的... 为提升区域互联电力系统静态电压稳定域边界(SVSRB)的构建效率,该文以直接法为基础,提出一种基于CPU-GPU异构的静态电压稳定域边界并行计算方法。该方法首先依据SVSRB拓扑特性,基于边界追踪算法实现直接法求解鞍结分岔(SNB)点时初值的高效选取,克服直接法对初值敏感这一瓶颈;然后结合CPU-GPU异构平台,将直接法求解SNB点计算量较大、计算耗时占比高的修正量求解部分由GPU完成,其他逻辑性强但计算量较低的部分由CPU完成,以实现SNB点的并行求解,降低直接法计算量大、计算复杂度高的不足,从而提升SVSRB的搜索效率;最后以WECC3机9节点测试系统,波兰电网2737节点和3120节点测试系统,欧洲电网7092节点、9241节点、11624节点和13659节点测试系统算例对该文所提方法进行了分析与验证,结果表明所提并行计算方法可实现电力系统静态电压稳定域边界的快速、准确搜索。 展开更多
关键词 静态电压稳定域边界 边界追踪法 直接法 鞍结分岔点 cpu-gpu 异构平台
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