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A Trajectory-Oriented Carriageway-Based Road Network Data Model, Part 1: Background 被引量:10
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作者 LI Xiang LIN Hui 《Geo-Spatial Information Science》 2006年第1期65-70,共6页
This is the first of a three-part series of pape rs which introduces a general background of building trajectory-oriented road net work data models, including motivation, related works, and basic concepts. The p urpos... This is the first of a three-part series of pape rs which introduces a general background of building trajectory-oriented road net work data models, including motivation, related works, and basic concepts. The p urpose of the series is to develop a trajectory-oriented road network data mode l, namely carriageway-based road network data model (CRNM). Part 1 deals with t he modeling background. Part 2 proposes the principle and architecture of the CR NM. Part 3 investigates the implementation of the CRNM in a case study. In the p resent paper, the challenges of managing trajectory data are discussed. Then, de veloping trajectory-oriented road network data models is proposed as a solution and existing road network data models are reviewed. Basic representation approa ches of a road network are introduced as well as its constitution. 展开更多
关键词 TRAJECTORY road network data model CARRIAGEWAY GIS GIS-T
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A Trajectory-Oriented, Carriageway-Based Road Network Data Model,Part 2:Methodology 被引量:10
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作者 LI Xiang LIN Hui 《Geo-Spatial Information Science》 2006年第2期112-117,150,共7页
This is the second of a three-part series of papers which presents the principle and architecture of the CRNM, a trajectory-oriented, carriageway-based road network data model. The first part of the series has introdu... This is the second of a three-part series of papers which presents the principle and architecture of the CRNM, a trajectory-oriented, carriageway-based road network data model. The first part of the series has introduced a general background of building trajectory-oriented road network data models, including motivation, related works, and basic concepts. Based on it, this paper describs the CRNM in detail. At first, the notion of basic roadway entity is proposed and discussed. Secondly, carriageway is selected as the basic roadway entity after compared with other kinds of roadway, and approaches to representing other roadways with carriageways are introduced. At last, an overall architecture of the CRNM is proposed. 展开更多
关键词 TRAJECTORY road network data model CARRIAGEWAY GIS GIS-T
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A Trajectory-Oriented Carriageway-Based Road Network Data Model, Part 3: Implementation 被引量:6
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作者 LI Xiang LIN Hui 《Geo-Spatial Information Science》 2006年第3期201-205,共5页
This is the final of a three-part series of papers which mainly discusses the implementation issues of the CRNM. The first two papers in the series have introduced the modeling background and methodology, respectively... This is the final of a three-part series of papers which mainly discusses the implementation issues of the CRNM. The first two papers in the series have introduced the modeling background and methodology, respectively. An overall architecture of the CRNM has been proposed in the last paper. On the basis of the above discusses, a linear reference method (LRM) for providing spatial references for location points of a trajectory is developed. A case study is introduced to illustrate the application of the CRNM for modeling a road network in the real world is given. A comprehensive conclusion is given for the series of papers. 展开更多
关键词 TRAJECTORY road network data model CARRIAGEWAY GIS GIS-T
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Modeling TCP Incast Issue in Data Center Networks and an Adaptive Application-Layer Solution
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作者 Jin-Tang Luo Jie Xu Jian Sun 《Journal of Electronic Science and Technology》 CAS CSCD 2018年第1期84-91,共8页
In data centers, the transmission control protocol(TCP) incast causes catastrophic goodput degradation to applications with a many-to-one traffic pattern. In this paper, we intend to tame incast at the receiver-side a... In data centers, the transmission control protocol(TCP) incast causes catastrophic goodput degradation to applications with a many-to-one traffic pattern. In this paper, we intend to tame incast at the receiver-side application. Towards this goal, we first develop an analytical model that formulates the incast probability as a function of connection variables and network environment settings. We combine the model with the optimization theory and derive some insights into minimizing the incast probability through tuning connection variables related to applications. Then,enlightened by the analytical results, we propose an adaptive application-layer solution to the TCP incast.The solution equally allocates advertised windows to concurrent connections, and dynamically adapts the number of concurrent connections to the varying conditions. Simulation results show that our solution consistently eludes incast and achieves high goodput in various scenarios including the ones with multiple bottleneck links and background TCP traffic. 展开更多
关键词 Application-layer solution data center networks modelING transmission control protocol(TCP) incast
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Model-based predictive controller design for a class of nonlinear networked systems with communication delays and data loss
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作者 安宝冉 刘国平 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第8期211-216,共6页
This paper discusses the model-based predictive controller design of networked nonlinear systems with communica- tion delay and data loss. Based on the analysis of the closed-loop networked predictive control systems,... This paper discusses the model-based predictive controller design of networked nonlinear systems with communica- tion delay and data loss. Based on the analysis of the closed-loop networked predictive control systems, the model-based networked predictive control strategy can compensate for communication delay and data loss in an active way. The designed model-based predictive controller can also guarantee the stability of the closed-loop networked system. The simulation re- suits demonstrate the feasibility and efficacy of the proposed model-based predictive controller design scheme. 展开更多
关键词 communication delays data loss model-based networked predictive control
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Fault detection and diagnosis for data incomplete industrial systems with new Bayesian network approach 被引量:15
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作者 Zhengdao Zhang Jinlin Zhu Feng Pan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2013年第3期500-511,共12页
For the fault detection and diagnosis problem in largescale industrial systems, there are two important issues: the missing data samples and the non-Gaussian property of the data. However, most of the existing data-d... For the fault detection and diagnosis problem in largescale industrial systems, there are two important issues: the missing data samples and the non-Gaussian property of the data. However, most of the existing data-driven methods cannot be able to handle both of them. Thus, a new Bayesian network classifier based fault detection and diagnosis method is proposed. At first, a non-imputation method is presented to handle the data incomplete samples, with the property of the proposed Bayesian network classifier, and the missing values can be marginalized in an elegant manner. Furthermore, the Gaussian mixture model is used to approximate the non-Gaussian data with a linear combination of finite Gaussian mixtures, so that the Bayesian network can process the non-Gaussian data in an effective way. Therefore, the entire fault detection and diagnosis method can deal with the high-dimensional incomplete process samples in an efficient and robust way. The diagnosis results are expressed in the manner of probability with the reliability scores. The proposed approach is evaluated with a benchmark problem called the Tennessee Eastman process. The simulation results show the effectiveness and robustness of the proposed method in fault detection and diagnosis for large-scale systems with missing measurements. 展开更多
关键词 fault detection and diagnosis Bayesian network Gaussian mixture model data incomplete non-imputation.
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Problem of Standardization of Configuration Data in Wireless Sensor Networks: The Case of Routing Protocols 被引量:1
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作者 Thomas Djotio Ndie Judith Soulamite Nouho Noutat 《Wireless Sensor Network》 2012年第7期177-184,共8页
The exploitation of Wireless Sensor Networks (WSN) is constrained by limited power, low computing power and storage and short-range radio transmission. Many routing protocols respecting these constraints were develope... The exploitation of Wireless Sensor Networks (WSN) is constrained by limited power, low computing power and storage and short-range radio transmission. Many routing protocols respecting these constraints were developed but, it still lacks formal and standardized solutions being able to help in their configuration. The configuration management that responds to this concern is very important in this type of network. It consists of the definition of data models to configure and is very necessary for the good network performance. Tangible results were obtained in traditional networks with the emergence of NETCONF and YANG standards, but on the best of our humble knowledge there are none yet in WSNs. We propose in this paper wsn-routing-protocol, a YANG data model for routing protocols configuration in WSNs. Following our model, we propose two YANG configuration data models based on the latter: they are respectively aodv for AODV and rpl for RPL. 展开更多
关键词 N Sensor network ROUTING Protocols CONFIGURATION data model YANG
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Attacks and Countermeasures in Social Network Data Publishing
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作者 YANG Mengmeng ZHU Tianqing +1 位作者 ZHOU Wanlei XIANG Yang 《ZTE Communications》 2016年第B06期2-9,共8页
With the increasing prevalence of social networks, more and more social network data are published for many applications, such as social network analysis and data mining. However, this brings privacy problems. For exa... With the increasing prevalence of social networks, more and more social network data are published for many applications, such as social network analysis and data mining. However, this brings privacy problems. For example, adversaries can get sensitive information of some individuals easily with little background knowledge. How to publish social network data for analysis purpose while preserving the privacy of individuals has raised many concerns. Many algorithms have been proposed to address this issue. In this paper, we discuss this privacy problem from two aspects: attack models and countermeasures. We analyse privacy conceres, model the background knowledge that adversary may utilize and review the recently developed attack models. We then survey the state-of-the-art privacy preserving methods in two categories: anonymization methods and differential privacy methods. We also provide research directions in this area. 展开更多
关键词 social network data publishing attack model privacy preserving
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Predicting formation lithology from log data by using a neural network 被引量:6
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作者 Wang Kexiong Zhang Laibin 《Petroleum Science》 SCIE CAS CSCD 2008年第3期242-246,共5页
In order to increase drilling speed in deep complicated formations in Kela-2 gas field, Tarim Basin, Xinjiang, west China, it is important to predict the formation lithology for drilling bit optimization. Based on the... In order to increase drilling speed in deep complicated formations in Kela-2 gas field, Tarim Basin, Xinjiang, west China, it is important to predict the formation lithology for drilling bit optimization. Based on the conventional back propagation (BP) model, an improved BP model was proposed, with main modifications of back propagation of error, self-adapting algorithm, and activation function, also a prediction program was developed. The improved BP model was successfully applied to predicting the lithology of formations to be drilled in the Kela-2 gas field. 展开更多
关键词 Kela-2 gas field neural network improved back-propagation (BP) model log data lithology prediction
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BP Network Based Users’Interest Model in Mining WWW Cache
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作者 ZHANG Wei-feng XU Bao-wen +2 位作者 ZHANG Xiao-fang CUI Zi-feng ZHOU Xiao-yu 《Wuhan University Journal of Natural Sciences》 EI CAS 2006年第1期243-247,共5页
By analyzing the WWW Cache model, we bring forward a user-interest description method based on the fuzzy theory and user-interest inferential relations based on BP(baek propagation) neural network. By this method, t... By analyzing the WWW Cache model, we bring forward a user-interest description method based on the fuzzy theory and user-interest inferential relations based on BP(baek propagation) neural network. By this method, the users' interest in the WWW cache can be described and the neural network of users' interest can be constructed by positive spread of interest and the negative spread of errors. This neural network can infer the users' interest. This model is not the simple extension of the simple interest model, but the round improvement of the model and its related algorithm. 展开更多
关键词 WWW Internet Interest model neural network data mining
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Multivariable Dynamic Modeling for Molten Iron Quality Using Incremental Random Vector Functional-link Networks 被引量:4
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作者 Li ZHANG Ping ZHOU +2 位作者 He-da SONG Meng YUAN Tian-you CHAI 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2016年第11期1151-1159,共9页
Molten iron temperature as well as Si, P, and S contents is the most essential molten iron quality (MIQ) indices in the blast furnace (BF) ironmaking, which requires strict monitoring during the whole ironmaking p... Molten iron temperature as well as Si, P, and S contents is the most essential molten iron quality (MIQ) indices in the blast furnace (BF) ironmaking, which requires strict monitoring during the whole ironmaking production. However, these MIQ parameters are difficult to be directly measured online, and large-time delay exists in off-line analysis through laboratory sampling. Focusing on the practical challenge, a data-driven modeling method was presented for the prediction of MIQ using the improved muhivariable incremental random vector functional-link net- works (M-I-RVFLNs). Compared with the conventional random vector functional-link networks (RVFLNs) and the online sequential RVFLNs, the M-I-RVFLNs have solved the problem of deciding the optimal number of hidden nodes and overcome the overfitting problems. Moreover, the proposed M I RVFLNs model has exhibited the potential for multivariable prediction of the MIQ and improved the terminal condition for the multiple-input multiple-out- put (MIMO) dynamic system, which is suitable for the BF ironmaking process in practice. Ultimately, industrial experiments and contrastive researches have been conducted on the BF No. 2 in Liuzhou Iron and Steel Group Co. Ltd. of China using the proposed method, and the results demonstrate that the established model produces better estima ting accuracy than other MIQ modeling methods. 展开更多
关键词 molten iron quality multivariable incremental random vector functional-link network blast furnace iron-making data-driven modeling principal component analysis
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Artificial Neural Network Model for Predicting Lung Cancer Survival 被引量:1
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作者 Hansapani Rodrigo Chris P. Tsokos 《Journal of Data Analysis and Information Processing》 2017年第1期33-47,共15页
The object of our present study is to develop a piecewise constant hazard model by using an Artificial Neural Network (ANN) to capture the complex shapes of the hazard functions, which cannot be achieved with conventi... The object of our present study is to develop a piecewise constant hazard model by using an Artificial Neural Network (ANN) to capture the complex shapes of the hazard functions, which cannot be achieved with conventional survival analysis models like Cox proportional hazard. We propose a more convenient approach to the PEANN created by Fornili et al. to handle a large amount of data. In particular, it provides much better prediction accuracies over both the Poisson regression and generalized estimating equations. This has been demonstrated with lung cancer patient data taken from the Surveillance, Epidemiology and End Results (SEER) program. The quality of the proposed model is evaluated by using several error measurement criteria. 展开更多
关键词 SURVIVAL Analysis HAZARD Prediction Artificial Neural network PIECEWISE EXPONENTIAL SURVIVAL model Censored data LUNG Cancer
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Modeling Reading and Replying Activities in a BBS Social Network 被引量:1
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作者 Fei Ding Yun Liu Bo Shen Hui Cheng 《Journal of Electronic Science and Technology》 CAS 2010年第4期300-306,共7页
This paper is devoted to analyze and model user reading and replying activities in a bulletin board system (BBS) social network. By analyzing the data set from a famous Chinese BBS social network, we show how some u... This paper is devoted to analyze and model user reading and replying activities in a bulletin board system (BBS) social network. By analyzing the data set from a famous Chinese BBS social network, we show how some user activities distribute, and reveal several important features that might characterize user dynamics. We propose a method to model user activities in the BBS social network. The model could reproduce power-law and non-power-law distributions of user activities at the same time. Our results show that user reading and replying activities could be simulated through simple agent-based models. Specifically, manners of how the BBS server interacts with Internet users in the Web 2.0 application, how users organize their reading lists, and how user behavioral trait distributes are the important factors in the formation of activity patterns. 展开更多
关键词 Agent based modeling bulletin boardsystem data analysis online social network.
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基于流动单元智能划分的湖泊-三角洲致密砂岩储层渗透率测井评价 被引量:1
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作者 赵天沛 赵勇 +4 位作者 谭茂金 李久娣 李博 王安龙 叶俊琦 《石油物探》 北大核心 2025年第2期388-396,共9页
在湖泊-三角洲沉积体系中,致密砂岩储层孔隙结构复杂且孔隙类型多样、渗透率低,此类储层的测井解释与评价面临挑战。渗透率是储层评价和产能预测的关键参数,传统的渗透率测井解释方法精度低,不能满足生产要求。针对这一难题,分析了影响... 在湖泊-三角洲沉积体系中,致密砂岩储层孔隙结构复杂且孔隙类型多样、渗透率低,此类储层的测井解释与评价面临挑战。渗透率是储层评价和产能预测的关键参数,传统的渗透率测井解释方法精度低,不能满足生产要求。针对这一难题,分析了影响储层渗透性的微观因素(孔隙结构)和宏观因素(流动单元),而且孔隙结构与流动单元密切相关,提出了岩石类型与流动单元指数(FZI)大小分类构建渗透率模型的方法。首先,分析岩心实验结果,确定岩石类型,计算岩心流动单元指数并利用累计频率法进行类型细分,针对每种类型构建相应的渗透率模型。然后,选取敏感测井实验构建标签,利用深度神经网络构建最佳模型,预测储层流动单元指数。最后,将孔隙度测井和流动单元指数代入相应的分类模型,计算出渗透率。将该方法应用于XH凹陷HG组低孔、低渗储层的渗透率预测进行应用,渗透率预测对数误差约为0.18,比利用深度神经网络直接预测渗透率的效果好。新的储层渗透率评价方法包括基于数据驱动的机器学习方法和基于机理或知识驱动的物理模型构建,体现了数模双驱智能思想,显著提高了致密砂岩储层渗透率测井评价精度,为其他湖泊-三角洲沉积体系储层渗透率预测提供了重要借鉴。 展开更多
关键词 湖泊-三角洲沉积 致密砂岩储层 流动单元指数 深度神经网络 数模双驱智能 渗透率评价
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Advances in Educational Data Mining Models and the Application of Its Algorithms
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作者 Chi Zhang Huan Yan +2 位作者 Ying Fu Guofeng Han Fan Feng 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2016年第6期32-40,共9页
In order to find an effective way to improve the quality of school management,finding valuable information from students' original data and providing feedback for student management are necessary. Firstly,some new... In order to find an effective way to improve the quality of school management,finding valuable information from students' original data and providing feedback for student management are necessary. Firstly,some new and successful educational data mining models were analyzed and compared. These models have better performance than traditional models( such as Knowledge Tracing Model) in efficiency,comprehensiveness,ease of use,stability and so on. Then,the neural network algorithm was conducted to explore the feasibility of the application of educational data mining in student management,and the results show that it has enough predictive accuracy and reliability to be put into practice. In the end,the possibility and prospect of the application of educational data mining in teaching management system for university students was assessed. 展开更多
关键词 educational data mining models student grade management neural network
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The application of hidden markov model in building genetic regulatory network
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作者 Rui-Rui Ji Ding Liu Wen Zhang 《Journal of Biomedical Science and Engineering》 2010年第6期633-637,共5页
The research hotspot in post-genomic era is from sequence to function. Building genetic regulatory network (GRN) can help to understand the regulatory mechanism between genes and the function of organisms. Probabilist... The research hotspot in post-genomic era is from sequence to function. Building genetic regulatory network (GRN) can help to understand the regulatory mechanism between genes and the function of organisms. Probabilistic GRN has been paid more attention recently. This paper discusses the Hidden Markov Model (HMM) approach served as a tool to build GRN. Different genes with similar expression levels are considered as different states during training HMM. The probable regulatory genes of target genes can be found out through the resulting states transition matrix and the determinate regulatory functions can be predicted using nonlinear regression algorithm. The experiments on artificial and real-life datasets show the effectiveness of HMM in building GRN. 展开更多
关键词 GENETIC REGULATORY network Hidden MARKOV model STATES TRANSITION GENE Expression data
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无线传感网络高维时序数据状态估计算法研究 被引量:1
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作者 邓俊华 屠敏 《传感技术学报》 北大核心 2025年第2期356-361,共6页
无线传感网络中数据量较大,准确估计存储节点中的数据状态,可以避免传感网络受高维度、冗余数据、网络状态等问题的干扰,进而提高传感网络的安全性。然而在传感网络中,对高维时序数据的状态估计一直是一个难点问题,为此,提出一种无线传... 无线传感网络中数据量较大,准确估计存储节点中的数据状态,可以避免传感网络受高维度、冗余数据、网络状态等问题的干扰,进而提高传感网络的安全性。然而在传感网络中,对高维时序数据的状态估计一直是一个难点问题,为此,提出一种无线传感网络高维时序数据状态估计算法。采用基于信息熵的PCA降维算法对传感节点中的高维时序数据进行降维处理,基于最优集成随机森林算法提取数据的特征,将提取的状态特征数据输入到贝叶斯估计模型中,并采用粒子滤波对模型求解,完成无线传感网络高维时序数据的状态估计。仿真结果表明:所提算法的估计时间始终在1.99 s以下,节点能耗小于22.1 J,估计结果与实际结果一致,具有良好的估计效果。 展开更多
关键词 无线传感网络 数据状态估计 贝叶斯估计模型 粒子滤波 高维时序数据 信息熵
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Building Bayesian Network(BN)-Based System Reliability Model by Dual Genetic Algorithm(DGA)
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作者 游威振 钟小品 《Journal of Donghua University(English Edition)》 EI CAS 2015年第6期914-918,共5页
A system reliability model based on Bayesian network(BN)is built via an evolutionary strategy called dual genetic algorithm(DGA).BN is a probabilistic approach to analyze relationships between stochastic events.In con... A system reliability model based on Bayesian network(BN)is built via an evolutionary strategy called dual genetic algorithm(DGA).BN is a probabilistic approach to analyze relationships between stochastic events.In contrast with traditional methods where BN model is built by professionals,DGA is proposed for the automatic analysis of historical data and construction of BN for the estimation of system reliability.The whole solution space of BN structures is searched by DGA and a more accurate BN model is obtained.Efficacy of the proposed method is shown by some literature examples. 展开更多
关键词 Bayesian network(BN)model dual genetic algorithm(DGA) system reliability historical data
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基于时序卷积网络的低压柔性互联配电网短期最大供电能力评估
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作者 彭寒梅 肖千皓 +2 位作者 谭貌 苏永新 李辉 《南方电网技术》 北大核心 2025年第10期111-120,共10页
低压柔性互联将同一区域配电网的低压台区间形成互联互供,可提高配电系统的最大供电能力(total supply capability,TSC),且低压台区接入的分布式能源具有时序性和不确定性,影响TSC值的变动。为此,提出了一种基于时序卷积神经网络(tempor... 低压柔性互联将同一区域配电网的低压台区间形成互联互供,可提高配电系统的最大供电能力(total supply capability,TSC),且低压台区接入的分布式能源具有时序性和不确定性,影响TSC值的变动。为此,提出了一种基于时序卷积神经网络(temporal convolutional network,TCN)的低压柔性互联配电网短期TSC评估方法,以兼具快速性和准确性。首先,进行低压柔性互联配电网短期TSC分析,建立基于数据驱动的短期TSC评估架构;然后,采用模型驱动的短期TSC评估方法,得到短期TSC值以获得训练样本,再离线训练TCN模型,得到短期TSC值与具有一定时序性的影响因素间非线性映射的TCN模型,实现由TCN在线评估系统短期TSC。最后,低压柔性互联配电网算例系统测试验证了所提方法的有效性。 展开更多
关键词 低压柔性互联 短期最大供电能力 时序卷积网络 模型驱动 数据驱动
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数字化背景下互联网创业数据风险预警模型 被引量:2
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作者 苏越良 杜芷晴 《系统工程学报》 北大核心 2025年第2期215-231,共17页
数字化背景下,数据已成为互联网创业的核心资产,在数据流上的不当行为可能对企业造成潜在损失.选取互联网创业的典型代表共享单车为例,提出数据流与数据风险的定义与内涵,构建并解释数字化互联网企业数据风险体系与数据风险复杂网络.根... 数字化背景下,数据已成为互联网创业的核心资产,在数据流上的不当行为可能对企业造成潜在损失.选取互联网创业的典型代表共享单车为例,提出数据流与数据风险的定义与内涵,构建并解释数字化互联网企业数据风险体系与数据风险复杂网络.根据其网络结构特征,利用PageRank算法与负荷-容量模型,并结合蚁群算法模拟复杂网络的相继故障,得到最高风险传播路径,由此搭建风险预警模型.通过分析共享单车失败和成功案例讨论模型的实现机制和实践价值,为互联网企业数据风险预知以及如何管理数据风险提供了直接有效的参考和判断依据,有助于企业实现数据闭环的良性循环;在经济上,促进数据资产的积极流动以创造更大效益. 展开更多
关键词 数字化 互联网创业 数据风险 风险预警模型 复杂网络
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