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A cloud model target damage effectiveness assessment algorithm based on spatio-temporal sequence finite multilayer fragments dispersion
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作者 Hanshan Li Xiaoqian Zhang Junchai Gao 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第10期48-64,共17页
To solve the problem of target damage assessment when fragments attack target under uncertain projectile and target intersection in an air defense intercept,this paper proposes a method for calculating target damage p... To solve the problem of target damage assessment when fragments attack target under uncertain projectile and target intersection in an air defense intercept,this paper proposes a method for calculating target damage probability leveraging spatio-temporal finite multilayer fragments distribution and the target damage assessment algorithm based on cloud model theory.Drawing on the spatial dispersion characteristics of fragments of projectile proximity explosion,we divide into a finite number of fragments distribution planes based on the time series in space,set up a fragment layer dispersion model grounded in the time series and intersection criterion for determining the effective penetration of each layer of fragments into the target.Building on the precondition that the multilayer fragments of the time series effectively assail the target,we also establish the damage criterion of the perforation and penetration damage and deduce the damage probability calculation model.Taking the damage probability of the fragment layer in the spatio-temporal sequence to the target as the input state variable,we introduce cloud model theory to research the target damage assessment method.Combining the equivalent simulation experiment,the scientific and rational nature of the proposed method were validated through quantitative calculations and comparative analysis. 展开更多
关键词 Target damage cloud model Fragments dispersion Effectiveness assessment Spatio-temporal sequence
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Research on BIM Model Reshaping Method Based on 3D Point Cloud Recognition
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作者 SHI Jin-yu YU Xian-feng +1 位作者 SI Zhan-jun ZHANG Ying-xue 《印刷与数字媒体技术研究》 CAS 北大核心 2024年第4期125-135,共11页
In view of the limitations of traditional measurement methods in the field of building information,such as complex operation,low timeliness and poor accuracy,a new way of combining three-dimensional scanning technolog... In view of the limitations of traditional measurement methods in the field of building information,such as complex operation,low timeliness and poor accuracy,a new way of combining three-dimensional scanning technology and BIM(Building Information Modeling)model was discussed.Focused on the efficient acquisition of building geometric information using the fast-developing 3D point cloud technology,an improved deep learning-based 3D point cloud recognition method was proposed.The method optimised the network structure based on RandLA-Net to adapt to the large-scale point cloud processing requirements,while the semantic and instance features of the point cloud were integrated to significantly improve the recognition accuracy and provide a precise basis for BIM model remodeling.In addition,a visual BIM model generation system was developed,which systematically transformed the point cloud recognition results into BIM component parameters,automatically constructed BIM models,and promoted the open sharing and secondary development of models.The research results not only effectively promote the automation process of converting 3D point cloud data to refined BIM models,but also provide important technical support for promoting building informatisation and accelerating the construction of smart cities,showing a wide range of application potential and practical value. 展开更多
关键词 3D point cloud RandLA-Net network BIM model OSG engine
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Guaranteed Cost Control for Uncertain Nonlinear Time-Delay Neutral Systems Based on T-S Fuzzy Model 被引量:1
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作者 GUO Xi-jin YAN Jun-rong WU Zhong-qiang 《Journal of China University of Mining and Technology》 EI 2005年第3期241-246,共6页
The problem of guaranteed cost fuzzy controller is studied for a class of nonlinear time-delay neutral sys-tems with norm-bounded uncertainty based on T-S model. The sufficient conditions are first derived for the exi... The problem of guaranteed cost fuzzy controller is studied for a class of nonlinear time-delay neutral sys-tems with norm-bounded uncertainty based on T-S model. The sufficient conditions are first derived for the existenceof guaranteed cost fuzzy controllers. These sufficient conditions are equivalent to a kind of linear matrix inequalities.Furthermore, a convex optimization problem with LMI constraints is formulated to design the optimal guaranteedcost controller. 展开更多
关键词 t-s model UNCERTAINTIES neutral system guaranteed cost control linear matrix inequalities
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Fault tolerant synchronization of chaotic systems based on T-S fuzzy model with fuzzy sampled-data controller 被引量:1
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作者 马大中 张化光 +1 位作者 王占山 冯健 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第5期104-114,共11页
In this paper the fault tolerant synchronization of two chaotic systems based on fuzzy model and sample data is investigated. The problem of fault tolerant synchronization is formulated to study the global asymptotica... In this paper the fault tolerant synchronization of two chaotic systems based on fuzzy model and sample data is investigated. The problem of fault tolerant synchronization is formulated to study the global asymptotical stability of the error system with the fuzzy sampled-data controller which contains a state feedback controller and a fault compensator. The synchronization can be achieved no matter whether the fault occurs or not. To investigate the stability of the error system and facilitate the design of the fuzzy sampled-data controller, a Takagi Sugeno (T-S) fuzzy model is employed to represent the chaotic system dynamics. To acquire good performance and produce a less conservative analysis result, a new parameter-dependent Lyapunov-Krasovksii functional and a relaxed stabilization technique are considered. The stability conditions based on linear matrix inequality are obtained to achieve the fault tolerant synchronization of the chaotic systems. Finally, a numerical simulation is shown to verify the results. 展开更多
关键词 fault tolerant synchronization fuzzy sampled-data controller Takagi-Sugeno t-s fuzzy model linear matrix inequality (LMI)
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Impulsive Control for T-S Fuzzy Model Based Chaotic Systems Consisting of Van der Pol Oscillators Coupled to Linear Oscillators 被引量:2
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作者 Qi-Shui Zhong Jing-Fu Bao Zhu-Sheng Kang 《Journal of Electronic Science and Technology of China》 2007年第4期348-351,共4页
This paper proposes an impulsive control scheme for chaotic systems consisting of Van der Pol oscillators coupled to linear oscillators (VDPL) based on their Takagi-Sugeno (T-S) fuzzy models. A T-S fuzzy model is ... This paper proposes an impulsive control scheme for chaotic systems consisting of Van der Pol oscillators coupled to linear oscillators (VDPL) based on their Takagi-Sugeno (T-S) fuzzy models. A T-S fuzzy model is utilized to represent the chaotic VDPL system. By using comparison method, a general asymptotical stability criterion by means of linear matrix inequality (LMI) is derived for the T-S fuzzy model of VDPL system with impulsive effects. The simulation results demonstrate the effectiveness of the proposed scheme. 展开更多
关键词 Impulsive control t-s fuzzy model CHAOS Van der Pol oscillator.
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Generating Li-Yorke chaos in a stable continuous-time T-S fuzzy model via time-delay feedback control
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作者 孙秋野 张化光 赵琰 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第7期141-149,共9页
This paper investigates the chaotification problem of a stable continuous-time T S fuzzy system. A simple nonlinear state time-delay feedback controller is designed by parallel distributed compensation technique. Then... This paper investigates the chaotification problem of a stable continuous-time T S fuzzy system. A simple nonlinear state time-delay feedback controller is designed by parallel distributed compensation technique. Then, the asymptotically approximate relationship between the controlled continuous-time T-S fuzzy system with time-delay and a discrete-time T-S fuzzy system is established. Based on the discrete-time T-S fuzzy system, it proves that the chaos in the discrete- time T-S fuzzy system satisfies the Li-Yorke definition by choosing appropriate controller parameters via the revised Marotto theorem. Finally, the effectiveness of the proposed chaotic anticontrol method is verified by a practical example. 展开更多
关键词 CHAOTIFICATION t-s fuzzy model time-delay feedback Li Yorke chaos 1
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Robust Non-Fragile Guaranteed Cost Control for Nonlinear Time Delay Discrete-Time Systems Based on T-S Model
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作者 Yu-Ping Zhang Hong Zhu Shou-Ming Zhong 《Journal of Electronic Science and Technology of China》 2007年第2期153-158,共6页
This paper concerns the robust non-fragile guaranteed cost control for nonlinear time delay discrete-time systems based on Takagi-Sugeno (T-S) model. The problem is to design a guaranteed cost state feedback control... This paper concerns the robust non-fragile guaranteed cost control for nonlinear time delay discrete-time systems based on Takagi-Sugeno (T-S) model. The problem is to design a guaranteed cost state feedback controller which can tolerate uncertainties from both models and gain variation. Sufficient conditions for the existence of such controller are given based on the linear matrix inequality (LMI) approach combined with Lyapunov method and inequality technique. A numerical example is given to illustrate the feasibility and effectiveness of our result. 展开更多
关键词 Guaranteed cost control linear matrix Inequality non-fragil e control robust control t-s model.
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基于T-S云模型的非线性网络化控制系统保性能鲁棒容错控制 被引量:4
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作者 蒋栋年 李炜 王君 《兰州理工大学学报》 CAS 北大核心 2012年第1期75-82,共8页
基于T-S云模型对一类具有参数不确定的非线性网络化控制系统,考虑网络延时和丢包的影响,通过构造Lyapunov-Krasovskii泛函,推证出确保非线性网络化控制系统在执行器或传感器发生失效故障时具有保性能鲁棒容错性能的时滞依赖充分条件,并... 基于T-S云模型对一类具有参数不确定的非线性网络化控制系统,考虑网络延时和丢包的影响,通过构造Lyapunov-Krasovskii泛函,推证出确保非线性网络化控制系统在执行器或传感器发生失效故障时具有保性能鲁棒容错性能的时滞依赖充分条件,并以求解线性或非线性矩阵不等式的方式给出控制器的设计方法.最后以一个仿真算例验证文中所述方法的可行性和有效性. 展开更多
关键词 网络化控制系统 t-s云模型 保性能 容错控制
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基于T-S云推理网络的板形智能控制对比研究 被引量:3
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作者 张秀玲 赵文保 +1 位作者 徐腾 赵亮 《中南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2013年第11期4461-4467,共7页
将具有处理数据不确定性的云模型和T-S模糊神经网络相结合,设计T-S云推理网络,基于此网络,建立板形识别模型和轧机板形预测模型。针对900HC可逆冷轧机,设计板形控制系统,研发一种简捷的控制器;基于900HC的实测数据先离线训练确定控制器... 将具有处理数据不确定性的云模型和T-S模糊神经网络相结合,设计T-S云推理网络,基于此网络,建立板形识别模型和轧机板形预测模型。针对900HC可逆冷轧机,设计板形控制系统,研发一种简捷的控制器;基于900HC的实测数据先离线训练确定控制器的初始参数,再在线调整控制器的参数,调整方法使用误差反传算法,并与具有相同结构的T-S模糊控制器进行对比。研究结果表明:此系统具有有效性和较好的鲁棒性。 展开更多
关键词 云模型 T—S云推理网络 板形识别模型 轧机预测模型 板形控制
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MODEL RECONSTRUCTION FROM CLOUD DATA FOR RAPID PROTOTYPE MANUFACTURING 被引量:1
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作者 张丽艳 周儒荣 周来水 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2001年第2期170-175,共6页
Model reconstruction from points scanned on existing physical objects is much important in a variety of situations such as reverse engineering for mechanical products, computer vision and recovery of biological shapes... Model reconstruction from points scanned on existing physical objects is much important in a variety of situations such as reverse engineering for mechanical products, computer vision and recovery of biological shapes from two dimensional contours. With the development of measuring equipment, cloud points that contain more details of the object can be obtained conveniently. On the other hand, large quantity of sampled points brings difficulties to model reconstruction method. This paper first presents an algorithm to automatically reduce the number of cloud points under given tolerance. Triangle mesh surface from the simplified data set is reconstructed by the marching cubes algorithm. For various reasons, reconstructed mesh usually contains unwanted holes. An approach to create new triangles is proposed with optimized shape for covering the unexpected holes in triangle meshes. After hole filling, watertight triangle mesh can be directly output in STL format, which is widely used in rapid prototype manufacturing. Practical examples are included to demonstrate the method. 展开更多
关键词 reverse engineering model reconstruction cloud data data filtering hole filling
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MTBAC: A Mutual Trust Based Access Control Model in Cloud Computing 被引量:12
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作者 LIN Guoyuan WANG Danru +1 位作者 BIE Yuyu LEI Min 《China Communications》 SCIE CSCD 2014年第4期154-162,共9页
As a new computing mode,cloud computing can provide users with virtualized and scalable web services,which faced with serious security challenges,however.Access control is one of the most important measures to ensure ... As a new computing mode,cloud computing can provide users with virtualized and scalable web services,which faced with serious security challenges,however.Access control is one of the most important measures to ensure the security of cloud computing.But applying traditional access control model into the Cloud directly could not solve the uncertainty and vulnerability caused by the open conditions of cloud computing.In cloud computing environment,only when the security and reliability of both interaction parties are ensured,data security can be effectively guaranteed during interactions between users and the Cloud.Therefore,building a mutual trust relationship between users and cloud platform is the key to implement new kinds of access control method in cloud computing environment.Combining with Trust Management(TM),a mutual trust based access control(MTBAC) model is proposed in this paper.MTBAC model take both user's behavior trust and cloud services node's credibility into consideration.Trust relationships between users and cloud service nodes are established by mutual trust mechanism.Security problems of access control are solved by implementing MTBAC model into cloud computing environment.Simulation experiments show that MTBAC model can guarantee the interaction between users and cloud service nodes. 展开更多
关键词 cloud computing access control trust model mutual trust mechanism MTBAC
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A Unified Framework of the Cloud Computing Service Model 被引量:2
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作者 Wen-Lung Shiau Chao-Ming Hsiao 《Journal of Electronic Science and Technology》 CAS 2013年第2期150-160,共11页
After a comprehensive literature review and analysis, a unified cloud computing framework is proposed, which comprises MapReduce, a vertual machine, Hadoop distributed file system (HDFS), Hbase, Hadoop, and virtuali... After a comprehensive literature review and analysis, a unified cloud computing framework is proposed, which comprises MapReduce, a vertual machine, Hadoop distributed file system (HDFS), Hbase, Hadoop, and virtualization. This study also compares Microsoft, Trend Micro, and the proposed unified cloud computing architecture to show that the proposed unified framework of the cloud computing service model is comprehensive and appropriate for the current complexities of businesses. The findings of this study can contribute to the knowledge for academics and practitioners to understand, assess, and analyze a cloud computing service application. 展开更多
关键词 cloud computing service model conceptual framework EVOLUTION information system.
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Comprehensive evaluation of 5G+smart distribution network based on combined weighting method-cloud model 被引量:7
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作者 Xiufan Ma Ying Wang +1 位作者 Zihao Liu Xiaoyu Feng 《Global Energy Interconnection》 EI CAS CSCD 2022年第6期675-691,共17页
With the large-scale application of 5G technology in smart distribution networks,the operation effects of distribution networks are not clear.Herein,we propose a comprehensive evaluation model of a 5G+smart distributi... With the large-scale application of 5G technology in smart distribution networks,the operation effects of distribution networks are not clear.Herein,we propose a comprehensive evaluation model of a 5G+smart distribution network based on the combination weighting and cloud model of the improved Fuzzy Analytic Hierarchy-Entropy Weight Method(FAHP-EWM).First,we establish comprehensive evaluation indexes of a 5G+smart distribution network from five dimensions:reliable operation,economic operation,efficient interaction,technological intelligence,and green emission reduction.Second,by introducing the principle of variance minimization,we propose a combined weighting method based on the improved FAHP-EWM to calculate the comprehensive weight,so as to reduce the defects of subjective arbitrariness and promote objectivity.Finally,a comprehensive evaluation model of 5G+smart distribution network based on cloud model is proposed by considering the uncertainty of distribution network node information and equipment status information.The example analysis indicates that the overall operation of the 5G+smart distribution network project is decent,and the weight value calculated by the combined weighting method is more reasonable and accurate than that calculated by the single weighting method,which verifies the effectiveness and rationality of the proposed evaluation method.Moreover,the proposed evaluation method has a certain guiding role for the large-scale application of 5G communication technology in smart distribution networks. 展开更多
关键词 5G+smart distribution network Comprehensive evaluation Improved FAHP Variance minimization Normal cloud model
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User’s Relevance of PIR System Based on Cloud Models 被引量:1
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作者 康海燕 樊孝忠 《Journal of Beijing Institute of Technology》 EI CAS 2006年第2期181-185,共5页
A new method to evaluate fuzzily user's relevance on the basis of cloud models has been proposed. All factors of personalized information retrieval system are taken into account in this method. So using this method f... A new method to evaluate fuzzily user's relevance on the basis of cloud models has been proposed. All factors of personalized information retrieval system are taken into account in this method. So using this method for personalized information retrieval (PIR) system can efficiently judge multi-value relevance, such as quite relevant, comparatively relevant, commonly relevant, basically relevant and completely non-relevant, and realize a kind of transform of qualitative concepts and quantity and improve accuracy of relevance judgements in PIR system. Experimental data showed that the method is practical and valid. Evaluation results are more accurate and approach to the fact better. 展开更多
关键词 personalized information retrieval (PIR) cloud model user's relevance fuzzy evaluation
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Advanced User-Based Interaction Model in Cloud 被引量:1
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作者 徐赢颖 敖乃翔 +2 位作者 黄丹 赵永祥 陈常嘉 《China Communications》 SCIE CSCD 2013年第4期126-134,共9页
With the increasing popularity of cloud computing, there is an increased de mand for cloud resources in cloud. It has be come even more urgent to find solutions to improve resource utilization. From the per spective o... With the increasing popularity of cloud computing, there is an increased de mand for cloud resources in cloud. It has be come even more urgent to find solutions to improve resource utilization. From the per spective of a cloud consumer, a cloud applica tion processes a large information flow in volving user actions that access resources, but little work has so far been devoted to research from the perspective of the interaction be tween the user and the cloud application. In this paper, we analyze the interaction in detail, and propose a general mathematical interac tion model to formulate the challenge pertain ing to storage resource allocation as an opti mization problem, focusing on minimizing both the user's cost and server's consumption. A potential response mechanism is then de signed based on the interaction model. Fur thermore, the proposed model is used to ex plore strategies when multiple users access the same file simultaneously. Additionally, an improved queuing system, namely M/ G~ oo queue with standby, is introduced. Finally, an evaluation is presented to verify the interac- tion model. 展开更多
关键词 interaction model cloud responsemechanism user data queuing system
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Task Partition Technology of pXCube Cloud Model
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作者 赵亚伟 《China Communications》 SCIE CSCD 2011年第6期93-99,共7页
Query efficiency is bottleneck of XML data cube aggregate query. pXCube is a kind of XML data cube model based on path calculation. Join operations are avoided in this model, but the query efficiency of fact cell is b... Query efficiency is bottleneck of XML data cube aggregate query. pXCube is a kind of XML data cube model based on path calculation. Join operations are avoided in this model, but the query efficiency of fact cell is become a new bottleneck. This paper focuses on parallel technology of cloud computing to improve query efficiency of pXCube. Mixed partitioning strategy for fact and dimensions is applied in pXCube cloud model, and the same partitioned vector is adopted. Query parallel algorithm of pXCube cloud model is presented as well. Experiments show that the query cost of pXCube cloud model decreases with the increasing number of parallel nodes gradually. The query cost of fact fragments of each node are close to or even lower than join operations of dimensions, and the Speedup is with better linear. So the model is well suited for decision supported query. 展开更多
关键词 pXCube cloud model PARTITION fact cell path query parallel DIMENSION
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Stability analysis and controller design of T-S fuzzy systems with time-delay under imperfect premise matching
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作者 张泽健 黄显林 +1 位作者 班晓军 高晓智 《Journal of Beijing Institute of Technology》 EI CAS 2012年第3期387-393,共7页
The issue of the stability and controller design of Takagi-Sugeno(T-S) fuzzy control systems with time-delay is investigated under imperfect premise matching when the T-S fuzzy time-delay model and fuzzy controller ... The issue of the stability and controller design of Takagi-Sugeno(T-S) fuzzy control systems with time-delay is investigated under imperfect premise matching when the T-S fuzzy time-delay model and fuzzy controller do not share the same membership functions.A new stability criterion which contains the information of membership functions is derived.The new stability criterion is less conservative,and enhances the design flexibility.Two numerical examples are presented to illustrate the conservativeness and effectiveness of the proposed method. 展开更多
关键词 t-s fuzzy model time-delay system stability analysis imperfect premise matching linear matrix inequality
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Cloudless-Training:基于serverless的高效跨地域分布式ML训练框架
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作者 谭文婷 吕存驰 +1 位作者 史骁 赵晓芳 《高技术通讯》 CAS 北大核心 2024年第3期219-232,共14页
跨地域分布式机器学习(ML)训练能够联合多区域的云资源协作训练,可满足许多新兴ML场景(比如大型模型训练、联邦学习)的训练需求。但其训练效率仍受2方面挑战的制约。首先,多区域云资源缺乏有效的弹性调度,这会影响训练的资源利用率和性... 跨地域分布式机器学习(ML)训练能够联合多区域的云资源协作训练,可满足许多新兴ML场景(比如大型模型训练、联邦学习)的训练需求。但其训练效率仍受2方面挑战的制约。首先,多区域云资源缺乏有效的弹性调度,这会影响训练的资源利用率和性能;其次,模型跨地域同步需要在广域网(WAN)上高频通信,受WAN的低带宽和高波动的影响,会产生巨大通信开销。本文提出Cloudless-Training,从3个方面实现高效的跨地域分布式ML训练。首先,它基于serverless计算模式实现,使用控制层和训练执行层的2层架构,支持多云区域的弹性调度和通信。其次,它提供一种弹性调度策略,根据可用云资源的异构性和训练数据集的分布自适应地部署训练工作流。最后,它提供了2种高效的跨云同步策略,包括基于梯度累积的异步随机梯度下降(ASGD-GA)和跨云参数服务器(PS)间的模型平均(MA)。Cloudless-Training是基于OpenFaaS实现的,并被部署在腾讯云上评估,实验结果表明Cloudless-Training可显著地提高跨地域分布式ML训练的资源利用率(训练成本降低了9.2%~24.0%)和同步效率(训练速度最多比基线快1.7倍),并能保证模型的收敛精度。 展开更多
关键词 跨地域分布式机器学习(ML)训练 跨云ML训练 分布式训练框架 serverless 跨云模型同步
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基于代理生成对抗网络的服务质量感知云API推荐系统投毒攻击
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作者 陈真 刘伟 +3 位作者 吕瑞民 马佳洁 冯佳音 尤殿龙 《通信学报》 北大核心 2025年第3期174-186,共13页
针对现有投毒攻击方法生成的虚假用户攻击数据存在攻击效果差且易被检测的不足,提出一种基于代理生成对抗网络的投毒攻击方法。首先,在生成对抗网络中采用K-means算法将数据分类,并引入自注意力机制学习每个类中的全局特征,解决生成对... 针对现有投毒攻击方法生成的虚假用户攻击数据存在攻击效果差且易被检测的不足,提出一种基于代理生成对抗网络的投毒攻击方法。首先,在生成对抗网络中采用K-means算法将数据分类,并引入自注意力机制学习每个类中的全局特征,解决生成对抗网络在数据稀疏时难以有效捕捉真实用户复杂行为模式这一问题,提升虚假用户的隐蔽性。其次,引入代理模型评估生成对抗网络生成的虚假用户的攻击效果,将评估结果作为代理损失优化生成对抗网络,进而实现在兼顾虚假用户隐蔽性的同时增强攻击效果。云API服务质量数据集上的实验表明,所提方法在兼顾攻击的有效性和隐蔽性方面均优于现有方法。 展开更多
关键词 推荐系统 云API 投毒攻击 生成对抗网络 代理模型
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面向局部点云信息缺失的模型重构方法
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作者 常正平 袁国帅 +2 位作者 李玖桦 赵阳 王仲奇 《工程科学与技术》 北大核心 2025年第2期54-63,共10页
面向新一代航空航天型号高性能制造需求,基于实测数据的性能预测方法愈来愈得到广泛应用。然而,受限于零件尺寸大、结构遮挡多和设备性能不足等问题,该方法难以获得零件完整的实测数据,影响了产品性能预测精度。为此,提出面向局部点云... 面向新一代航空航天型号高性能制造需求,基于实测数据的性能预测方法愈来愈得到广泛应用。然而,受限于零件尺寸大、结构遮挡多和设备性能不足等问题,该方法难以获得零件完整的实测数据,影响了产品性能预测精度。为此,提出面向局部点云缺失的模型重构方法,构建扫描区域与点云缺失区域的拓扑关系,求得缺失区域的表面点集。首先,提取理论3维模型表面几何信息,并将其转换至拉普拉斯坐标系;其次,将扫描点云数据进行划分,结合粗配准与迭代最近点(ICP)精配准算法进行区域匹配,得到理论模型上与扫描点云对应的区域;然后,采用拉普拉斯网格变换使匹配区域驱动理论三角网格发生形变,并用扫描点云替换对应区域,得到零件完整点云。最后,以飞机起落架外筒为例,采用传统方法与本文方法进行对比,发现当扫描点云覆盖达到一定范围时,所提方法的最大偏差为0.145 mm,显著低于传统方法的0.717 mm,验证了该方法在重构模型精度上的提升。 展开更多
关键词 局部点云 信息缺失 模型重构 拉普拉斯网格变换
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