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Multi-source information fused generative adversarial network model and data assimilation based history matching for reservoir with complex geologies 被引量:2
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作者 Kai Zhang Hai-Qun Yu +7 位作者 Xiao-Peng Ma Jin-Ding Zhang Jian Wang Chuan-Jin Yao Yong-Fei Yang Hai Sun Jun Yao Jian Wang 《Petroleum Science》 SCIE CAS CSCD 2022年第2期707-719,共13页
For reservoirs with complex non-Gaussian geological characteristics,such as carbonate reservoirs or reservoirs with sedimentary facies distribution,it is difficult to implement history matching directly,especially for... For reservoirs with complex non-Gaussian geological characteristics,such as carbonate reservoirs or reservoirs with sedimentary facies distribution,it is difficult to implement history matching directly,especially for the ensemble-based data assimilation methods.In this paper,we propose a multi-source information fused generative adversarial network(MSIGAN)model,which is used for parameterization of the complex geologies.In MSIGAN,various information such as facies distribution,microseismic,and inter-well connectivity,can be integrated to learn the geological features.And two major generative models in deep learning,variational autoencoder(VAE)and generative adversarial network(GAN)are combined in our model.Then the proposed MSIGAN model is integrated into the ensemble smoother with multiple data assimilation(ESMDA)method to conduct history matching.We tested the proposed method on two reservoir models with fluvial facies.The experimental results show that the proposed MSIGAN model can effectively learn the complex geological features,which can promote the accuracy of history matching. 展开更多
关键词 multi-source information Automatic history matching Deep learning Data assimilation Generative model
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Fault location of distribution networks based on multi-source information 被引量:8
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作者 Wenbo Li Jianjun Su +2 位作者 Xin Wang Jiamei Li Qian Ai 《Global Energy Interconnection》 2020年第1期77-85,共9页
In order to promote the development of the Internet of Things(IoT),there has been an increase in the coverage of the customer electric information acquisition system(CEIAS).The traditional fault location method for th... In order to promote the development of the Internet of Things(IoT),there has been an increase in the coverage of the customer electric information acquisition system(CEIAS).The traditional fault location method for the distribution network only considers the information reported by the Feeder Terminal Unit(FTU)and the fault tolerance rate is low when the information is omitted or misreported.Therefore,this study considers the influence of the distributed generations(DGs)for the distribution network.This takes the CEIAS as a redundant information source and solves the model by applying a binary particle swarm optimization algorithm(BPSO).The improved Dempster/S-hafer evidence theory(D-S evidence theory)is used for evidence fusion to achieve the fault section location for the distribution network.An example is provided to verify that the proposed method can achieve single or multiple fault locations with a higher fault tolerance. 展开更多
关键词 Internet of Things multi-source information D-S evidence theory Binary particle swarm optimization algorithm Fault tolerance
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Evaluating the dynamical coupling between spatiotemporally chaotic signals via an information theory approach
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作者 肖方红 郭少华 胡元太 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第7期1460-1463,共4页
An information-theoretic measure is introduced for evaluating the dynamical coupling of spatiotemporally chaotic signals produced by extended systems. The measure of the one-way coupled map lattices and the one-dimens... An information-theoretic measure is introduced for evaluating the dynamical coupling of spatiotemporally chaotic signals produced by extended systems. The measure of the one-way coupled map lattices and the one-dimensional, homogeneous, diffusively coupled map lattices is computed with the symbolic analysis method. The numerical results show that the information measure is applicable to determining the dynamical coupling between two directly coupled or indirectly coupled chaotic signals. 展开更多
关键词 spatiotemporal chaos information entropy dynamical coupling coupled map lattices
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Intervention against information diffusion in static and temporal coupling networks
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作者 柴允 王友国 +1 位作者 颜俊 孙先莉 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第9期116-127,共12页
Information diffusion in complex networks has become quite an active research topic.As an important part of this field,intervention against information diffusion processes is attracting ever-increasing attention from ... Information diffusion in complex networks has become quite an active research topic.As an important part of this field,intervention against information diffusion processes is attracting ever-increasing attention from network and control engineers.In particular,it is urgent to design intervention schemes for the coevolutionary dynamics between information diffusion processes and coupled networks.For this purpose,we comprehensively study the problem of information diffusion intervention over static and temporal coupling networks.First,individual interactions are described by a modified activitydriven network(ADN)model.Then,we establish a novel node-based susceptible-infected-recovered-susceptible(SIRS)model to characterize the information diffusion dynamics.On these bases,three synergetic intervention strategies are formulated.Second,we derive the critical threshold of the controlled-SIRS system via stability analysis.Accordingly,we exploit a spectral optimization scheme to minimize the outbreak risk or the required budget.Third,we develop an optimal control scheme of dynamically allocating resources to minimize both system loss and intervention expense,in which the optimal intervention inputs are obtained through optimal control theory and a forward-backward sweep algorithm.Finally,extensive simulation results validate the accuracy of theoretical derivation and the performance of our proposed intervention schemes. 展开更多
关键词 information diffusion coupling networks spectral optimization optimal control
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A multi-source information fusion method for tool life prediction based on CNN-SVM
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作者 Shuo WANG Zhenliang YU +1 位作者 Peng LIU Man Tong WANG 《Mechanical Engineering Science》 2022年第2期1-10,I0003,I0004,共12页
For milling tool life prediction and health management,accurate extraction and dimensionality reduction of its tool wear features are the key to reduce prediction errors.In this paper,we adopt multi-source information... For milling tool life prediction and health management,accurate extraction and dimensionality reduction of its tool wear features are the key to reduce prediction errors.In this paper,we adopt multi-source information fusion technology to extract and fuse the features of cutting vibration signal,cutting force signal and acoustic emission signal in time domain,frequency domain and time-frequency domain,and downscale the sample features by Pearson correlation coefficient to construct a sample data set;then we propose a tool life prediction model based on CNN-SVM optimized by genetic algorithm(GA),which uses CNN convolutional neural network as the feature learner and SVM support vector machine as the trainer for regression prediction.The results show that the improved model in this paper can effectively predict the tool life with better generalization ability,faster network fitting,and 99.85%prediction accuracy.And compared with the BP model,CNN model,SVM model and CNN-SVM model,the performance of the coefficient of determination R2 metric improved by 4.88%,2.96%,2.53%and 1.34%,respectively. 展开更多
关键词 CNN-SVM tool wear life prediction multi-source information fusion
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A guidance and control design with reduced information for a dual-spin stabilized projectile
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作者 Yu Wang Jiyan Yu +1 位作者 Xiaoming Wang Jia Fangxiu 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期494-505,共12页
In this paper,an integrated guidance and control method based on an adaptive path-following controller is proposed to control a spin-stabilized projectile with only translational motion information under the constrain... In this paper,an integrated guidance and control method based on an adaptive path-following controller is proposed to control a spin-stabilized projectile with only translational motion information under the constraint of an actuator,uncertainties in aerodynamic parameters and measurements,and control system complexity.Owing to the fairly high rotation speed,the dynamic model of this missile is strongly nonlinear,uncertain and coupled in pitch,yaw and roll channels.A theoretical equivalent resultant force and uncertainty compensation method are comprehensively used to realize decoupling of pitch and yaw.In response to the strong nonlinear and time-varying characteristics of the dynamic system,the quasi-linear model whose parameters are obtained by interpolation of points selected as the segmentation points in the trajectory envelope,is used for calculation in each step.To cope with the system uncertainty caused by model approximation,parameter uncertainty and ballistic interference,an extended state estimator is used to compensate the output feedback according to the test ballistic angle.In order to improve the tracking efficiency and ensure the tracking error convergence with only translational motion information,the virtual guide point,whose derivative is deduced according to the Lyapunov principle,is calculated in real time according to the projection relationship between the real-time position and the reference trajectory,and a virtual line-of-sight angle and the backstepping method are used for the design of the guidance and control system.In order to avoid the influence of control input saturation on the guidance and control performance due to the actuator limitation and improve the robustness of the system,an anti-saturation compensator is designed according to the two-step method.The feasibility and effectiveness of the path-following controller is verified through closed-loop flight simulations with measurement,control,and condition uncertainties.The results indicate that the designed controller can converge to the reference path and evidently decrease the distance between the impact point and target under different uncertainties. 展开更多
关键词 Spin-stabilized projectile Reduced information Path-following control Extended state observer coupled nonlinear system Input saturation
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Multi-segment and Multi-ply Overlapping Process of Multi Coupled Activities Based on Valid Information Evolution 被引量:1
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作者 WANG Zhiliang WANG Yunxia QIU Shenghai 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2013年第1期176-188,共13页
Complex product development will inevitably face the design planning of the multi-coupled activities, and overlapping these activities could potentially reduce product development time, but there is a risk of the addi... Complex product development will inevitably face the design planning of the multi-coupled activities, and overlapping these activities could potentially reduce product development time, but there is a risk of the additional cost. Although the downstream task information dependence to the upstream task is already considered in the current researches, but the design process overall iteration caused by the information interdependence between activities is hardly discussed; especially the impact on the design process' overall iteration from the valid information accumulation process. Secondly, most studies only focus on the single overlapping process of two activities, rarely take multi-segment and multi-ply overlapping process of multi coupled activities into account; especially the inherent link between product development time and cost which originates from the overlapping process of multi coupled activities. For the purpose of solving the above problems, as to the insufficiency of the accumulated valid information in overlapping process, the function of the valid information evolution (VIE) degree is constructed. Stochastic process theory is used to describe the design information exchange and the valid information accumulation in the overlapping segment, and then the planning models of the single overlapping segment are built. On these bases, by analyzing overlapping processes and overlapping features of multi-coupling activities, multi-segment and multi-ply overlapping planning models are built; by sorting overlapping processes and analyzing the construction of these planning models, two conclusions are obtained: (1) As to multi-segment and multi-ply overlapping of multi coupled activities, the total decrement of the task set development time is the sum of the time decrement caused by basic overlapping segments, and minus the sum of the time increment caused by multiple overlapping segments; (2) the total increment of development cost is the sum of the cost increment caused by all overlapping process. And then, based on overlapping degree analysis of these planning models, by the V1E degree function, the four lemmas theory proofs are represented, and two propositions are finally proved: (1) The multi-ply overlapping of the multi coupled activities will weaken the basic overlapping effect on the development cycle time reduction (2) Overlapping the multi coupled activities will decrease product development cycle, but increase product development cost. And there is trade-off between development time and cost. And so, two methods are given to slacken and eliminate multi-ply overlapping effects. At last, an example about a vehicle upper subsystem design illustrates the application of the proposed models; compared with a sequential execution pattern, the decreasing of development cycle (22%) and the increasing of development cost (3%) show the validity of the method in the example The proposed research not only lays a theoretical foundation for correctly planning complex product development process, but also provides specific and effective operation methods for overlapping multi coupled activities. 展开更多
关键词 multi coupled activities valid information evolution multi-segment multi-ply overlapping development time and cost trade-ofl iteration
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Structural damage detection method based on information fusion technique 被引量:1
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作者 刘涛 李爱群 +1 位作者 丁幼亮 费庆国 《Journal of Southeast University(English Edition)》 EI CAS 2008年第2期201-205,共5页
Multi-source information fusion (MSIF) is imported into structural damage diagnosis methods to improve the validity of damage detection. After the introduction of the basic theory, the function model, classification... Multi-source information fusion (MSIF) is imported into structural damage diagnosis methods to improve the validity of damage detection. After the introduction of the basic theory, the function model, classifications and mathematical methods of MSIF, a structural damage detection method based on MSIF is presented, which is to fuse two or more damage character vectors from different structural damage diagnosis methods on the character-level. In an experiment of concrete plates, modal information is measured and analyzed. The structural damage detection method based on MSIF is taken to localize cracks of concrete plates and it is proved to be effective. Results of damage detection by the method based on MSIF are compared with those from the modal strain energy method and the flexibility method. Damage, which can hardly be detected by using the single damage identification method, can be diagnosed by the damage detection method based on the character-level MSIF technique. Meanwhile multi-location damage can be identified by the method based on MSIF. This method is sensitive to structural damage and different mathematical methods for MSIF have different preconditions and applicabilities for diversified structures. How to choose mathematical methods for MSIF should be discussed in detail in health monitoring systems of actual structures. 展开更多
关键词 multi-source information fusion structural damage detection Bayes method D-S evidence theory
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Shannon information capacity of time reversal wideband multiple-input multiple-output system based on correlated statistical channels 被引量:1
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作者 杨瑜 王秉中 丁帅 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第5期5-10,共6页
Utilizing channel reciprocity, time reversal(TR) technique increases the signal-to-noise ratio(SNR) at the receiver with very low transmitter complexity in complex multipath environment. Present research works abo... Utilizing channel reciprocity, time reversal(TR) technique increases the signal-to-noise ratio(SNR) at the receiver with very low transmitter complexity in complex multipath environment. Present research works about TR multiple-input multiple-output(MIMO) communication all focus on the system implementation and network building. The aim of this work is to analyze the influence of antenna coupling on the capacity of wideband TR MIMO system, which is a realistic question in designing a practical communication system. It turns out that antenna coupling stabilizes the capacity in a small variation range with statistical wideband channel response. Meanwhile, antenna coupling only causes a slight detriment to the channel capacity in a wideband TR MIMO system. Comparatively, uncorrelated stochastic channels without coupling exhibit a wider range of random capacity distribution which greatly depends on the statistical channel. The conclusions drawn from information difference entropy theory provide a guideline for designing better high-performance wideband TR MIMO communication systems. 展开更多
关键词 information entropy time reversal wideband multiple-input multiple-output(MIMO) system antenna mutual coupling
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Decoding the Information of Life 被引量:1
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作者 ShantilalG. Goradia 《Journal of Physical Science and Application》 2015年第3期191-195,共5页
We link nuclear force with gravity. We use statistical entropy to link fine-structure constant (ct) and cosmological constant, showing mystical number 137 (as reciprocal of increasing entropy of the universe) as n... We link nuclear force with gravity. We use statistical entropy to link fine-structure constant (ct) and cosmological constant, showing mystical number 137 (as reciprocal of increasing entropy of the universe) as negative entropy needed for life to exist. If our computational route applies to the physical universe, it should apply to life. Molecular biology is searching for the fundamental source of information that would link to the information in DNA. 展开更多
关键词 3rd law of thermodynamics fine-structure constant cosmological constant strong coupling information.
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Information freshness optimization of multiple status update streams in Internet of things:Generation rate control and service rate reservation
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作者 Tianci Zhang Junjie Zhou +3 位作者 Zhengchuan Chen Zhong Tian Wanli Wen Yunjian Jia 《Digital Communications and Networks》 SCIE CSCD 2023年第4期971-980,共10页
The Internet of things(IoT)has become a key infrastructure providing up-to-date and fresh information for policy analysis and decision-making of upper-layer applications.However,there are limited sensing and communica... The Internet of things(IoT)has become a key infrastructure providing up-to-date and fresh information for policy analysis and decision-making of upper-layer applications.However,there are limited sensing and communication resources in IoT devices,which significantly affects the timeliness and freshness of the updated status.This work proposes two schemes,namely,the generation rate control and service rate reservation schemes,to improve the overall information freshness of multiple status update streams at the receiver.Specifically,using the recently proposed Age of Information(AoI)as the metric for evaluating information freshness,we characterized the overall information freshness,i.e.,the overall average AoI at the receiver for both schemes,by considering the urgency difference of status update and streams.Both schemes for status updates and streams,respectively,were formulated as two optimization problems.We proved that both problems are convex and the optimal generation and service rates for different streams are found by the standard convex optimization algorithm.Moreover,we proposed both approximate optimal generation and approximate optimal service rate for fast deployment in heavy and light load cases.Numerical results verify the theoretical findings and accuracy of the proposed approximate solutions,guiding the design and deployment of IoT. 展开更多
关键词 Internet of things information freshness Age of information multi-source M/M/1 queuing model
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Investigations into Capacity of MIMO Ad Hoc Network Including Effects of Antenna Mutual Coupling
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作者 Xia LIU Marek E. BIALKOWSKI +1 位作者 Feng WANG Konglit HUNCHANGSITH 《Wireless Sensor Network》 2009年第5期425-433,共9页
This paper reports on investigations into capacity of ad hoc network whose nodes are equipped with multiple element antennas (MEAs). The investigation of this multi-user Multiple Input Multiple Output (MIMO) system ta... This paper reports on investigations into capacity of ad hoc network whose nodes are equipped with multiple element antennas (MEAs). The investigation of this multi-user Multiple Input Multiple Output (MIMO) system takes into account mutual coupling (MC) in addition to spatial correlation that is present in array antennas. A closed-form expression for an upper bound of mutual information (capacity) of MIMO ad hoc network is derived. An optimal signal transmission scheme is proposed to maximize the MIMO ad hoc network capacity. Simulation results for capacity of non-optimized and optimized cases of signal transmission are presented. 展开更多
关键词 MIMO Ad HOC Network Channel Capacity Mutual information Mutual coupling Spatial Correlation
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A taxonomy of built asset information coupling
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作者 Saman DAVARI Erik POIRIER 《Frontiers of Engineering Management》 CSCD 2024年第2期247-268,共22页
The digital transformation of the built asset industry is moving toward closer integration of physical and digital assets and resources.Within the framework of Cyber-Physical Systems(CPSs)and Digital Twins(DTs),an inc... The digital transformation of the built asset industry is moving toward closer integration of physical and digital assets and resources.Within the framework of Cyber-Physical Systems(CPSs)and Digital Twins(DTs),an increasing number of studies focus on the technical aspects of CPS and DT.However,a unified framework describing the dimensions and characteristics essential for integrating lifecycle information remains elusive.To leverage these concepts effectively,it is necessary to develop new frameworks to classify and put into relationship various components that comprise the lifecycle information integration of physical and digital assets and resources.This paper addresses these gaps by proposing a taxonomy of Built Asset Lifecycle Information Couples,which outlines the dimensions and characteristics crucial for the lifecycle information integration of built assets and resources.The proposed taxonomy contributes to the efforts aimed at organizing the knowledge domain of lifecycle information management in the built environment. 展开更多
关键词 asset coupling TAXONOMY DIGITALIZATION lifecycle information management built environment
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An improved pulse coupled neural networks model for semantic IoT
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作者 Rong Ma Zhen Zhang +3 位作者 Yide Ma Xiping Hu Edith C.H.Ngai Victor C.M.Leung 《Digital Communications and Networks》 SCIE CSCD 2024年第3期557-567,共11页
In recent years,the Internet of Things(IoT)has gradually developed applications such as collecting sensory data and building intelligent services,which has led to an explosion in mobile data traffic.Meanwhile,with the... In recent years,the Internet of Things(IoT)has gradually developed applications such as collecting sensory data and building intelligent services,which has led to an explosion in mobile data traffic.Meanwhile,with the rapid development of artificial intelligence,semantic communication has attracted great attention as a new communication paradigm.However,for IoT devices,however,processing image information efficiently in real time is an essential task for the rapid transmission of semantic information.With the increase of model parameters in deep learning methods,the model inference time in sensor devices continues to increase.In contrast,the Pulse Coupled Neural Network(PCNN)has fewer parameters,making it more suitable for processing real-time scene tasks such as image segmentation,which lays the foundation for real-time,effective,and accurate image transmission.However,the parameters of PCNN are determined by trial and error,which limits its application.To overcome this limitation,an Improved Pulse Coupled Neural Networks(IPCNN)model is proposed in this work.The IPCNN constructs the connection between the static properties of the input image and the dynamic properties of the neurons,and all its parameters are set adaptively,which avoids the inconvenience of manual setting in traditional methods and improves the adaptability of parameters to different types of images.Experimental segmentation results demonstrate the validity and efficiency of the proposed self-adaptive parameter setting method of IPCNN on the gray images and natural images from the Matlab and Berkeley Segmentation Datasets.The IPCNN method achieves a better segmentation result without training,providing a new solution for the real-time transmission of image semantic information. 展开更多
关键词 Internet of things(IoT) Semantic information Real-time application Improved pulse coupled neural network Image segmentation
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Enhancing train position perception through Al-driven multi-source information fusion 被引量:2
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作者 Haifeng Song Zheyu Sun +3 位作者 Hongwei Wang Tianwei Qu Zixuan Zhang Hairong Dong 《Control Theory and Technology》 EI CSCD 2023年第3期425-436,共12页
This paper addresses the challenge of accurately and timely determining the position of a train,with specific consideration given to the integration of the global navigation satellite system(GNSS)and inertial navigati... This paper addresses the challenge of accurately and timely determining the position of a train,with specific consideration given to the integration of the global navigation satellite system(GNSS)and inertial navigation system(INS).To overcome the increasing errors in the INS during interruptions in GNSS signals,as well as the uncertainty associated with process and measurement noise,a deep learning-based method for train positioning is proposed.This method combines convolutional neural networks(CNN),long short-term memory(LSTM),and the invariant extended Kalman filter(IEKF)to enhance the perception of train positions.It effectively handles GNSS signal interruptions and mitigates the impact of noise.Experimental evaluation and comparisons with existing approaches are provided to illustrate the effectiveness and robustness of the proposed method. 展开更多
关键词 Train positioning Deep learning multi-source information fusion Dynamic adaptive model
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Coupling analysis-based false monitoring information identification of production system in process industry 被引量:1
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作者 GAO ZhiYong WANG RongXi +2 位作者 JIANG HongQuan GAO JianMin DONG RongGuang 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2017年第6期807-817,共11页
False monitoring information is a major problem in process production system and several ineffective methods have been proposed to identify false monitoring information in the production system. In this paper, a new m... False monitoring information is a major problem in process production system and several ineffective methods have been proposed to identify false monitoring information in the production system. In this paper, a new method is proposed to identify false monitoring information based on system coupling analysis and collision detection from the perspective of data analysis. Coupling multifractal features are extracted to reflect the changes in coupling relationship by utilizing the multifractal detrended cross-correlation analysis (MF-DXA). Each monitoring variable in process production system has more than one coupled variable, which can be regarded as multi-source. To achieve low redundancy in features and uniform description of coupling relationship, the feature level information fusion is studied based on modified Mahalanobis Taguchi system (MTS). False alarms are identified when the coupling relationships among the coupled monitoring variables collide. Analysis results of coupled R?ssler and Henon datasets indicate the feasibility of this method for selecting the effective coupling feature and uniform description of coupling relationship. The compressor system case of Coal Chemical Ltd. Group is studied and false monitoring information is identified. 展开更多
关键词 false monitoring information coupling analysis MF-DXA MTS process industry
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Integration Technique of Multi-source Information Dominated by Aerial Radiometric Measure-ment and Its Application
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作者 刘德长 孙茂荣 +2 位作者 朱德龄 张静波 何建国 《Science China Chemistry》 SCIE EI CAS 1994年第3期377-384,共8页
This paper aims at exploring a digital image integration technique for multi-geoscience in formation dominated by airborne gamma-ray data, especially deeply discussing the method to secondly develop those aerial data ... This paper aims at exploring a digital image integration technique for multi-geoscience in formation dominated by airborne gamma-ray data, especially deeply discussing the method to secondly develop those aerial data by combining digital image processing system with the colored mapping system. Utilizing this technique , we have analyzed the geologic environment of uranium mineralization of Lianshanguan area > Liaoning Province, provided some important background information for further seeking of minerals. Meanwhile , experimental studies have been made to predict uranium mineralization , and evident results aquired. Practise shows that this new technique offers prospecting significance for mineral seeking and great practical value in survey of uranium resources. 展开更多
关键词 multi-source information AERIAL radiometric measurement.
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Construction of Larger Area Density-Uniform Plasma with Collisional Inductively Coupled Plasma Cells
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作者 欧阳亮 刘万东 +6 位作者 白小燕 陈志鹏 王慧慧 李弘 罗辰 吉亮亮 胡北 《Plasma Science and Technology》 SCIE EI CAS CSCD 2007年第3期265-268,共4页
The plasma density and electron temperature of a multi-source plasma system composed of several collisional inductively coupled plasma (ICP) cells were measured by a doubleprobe. The discharges of the ICP cells were... The plasma density and electron temperature of a multi-source plasma system composed of several collisional inductively coupled plasma (ICP) cells were measured by a doubleprobe. The discharges of the ICP cells were shown to be independent of each other. Furthermore, the total plasma density at simultaneous multi-cell discharge was observed to be approximately equal to the summation of the plasma density when the cells discharge separately. Based on the linear summation phenomenon, it was shown that a larger area plasma with a uniform density and temperature profile could be constructed with multi-collisional ICP cells. 展开更多
关键词 inductively coupled plasma COLLISIONAL multi-source plasma cell
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Constructing Hash Function Based on Coupled Network Generated by Logarithmic Map
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作者 SONG Yu-rong JIANG Guo-ping 《南京邮电大学学报(自然科学版)》 2010年第1期6-10,共5页
In this paper,based on coupled network generated by chaotic logarithmic map,a novel algorithm for constructing hash functions is proposed,which can transform messages and can establish a mapping from the transformed m... In this paper,based on coupled network generated by chaotic logarithmic map,a novel algorithm for constructing hash functions is proposed,which can transform messages and can establish a mapping from the transformed messages to the coupled matrix of the network.The network model is carefully designed to ensure the network dynamics to be chaotic.Through the chaotic iterations of the network,quantization and exclusive-or (XOR) operations,the algorithm can construct hash value with arbitrary length.It is shown by simulations that the algorithm is extremely sensitive to the initial values and the coupled matrix of the network,and has excellent performance in one-way,confusion and diffusion,and collision resistance. 展开更多
关键词 计算机网络 应用程序 网络安全 网络协议
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基于熵权TOPSIS和耦合协调模型的四川省土地利用效益耦合协调关系及时空演变特征 被引量:1
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作者 谢贤健 《水土保持学报》 CSCD 北大核心 2024年第1期267-277,共11页
[目的]从社会、经济、生态环境3个方面评价区域土地利用效益及其耦合关系有利于实现土地资源的合理配置及优化用地结构。[方法]以四川省21个地市州为研究对象,利用熵权TOPSIS法和耦合协调度模型,构建了2010—2020年四川省土地利用效益... [目的]从社会、经济、生态环境3个方面评价区域土地利用效益及其耦合关系有利于实现土地资源的合理配置及优化用地结构。[方法]以四川省21个地市州为研究对象,利用熵权TOPSIS法和耦合协调度模型,构建了2010—2020年四川省土地利用效益的综合评价体系,并基于GIS技术,分析了土地利用的社会、经济、生态环境效益及其耦合协调关系的时空演变特征。[结果](1)四川省各地市州的土地利用综合效益整体上呈上升趋势,空间上具有“西北高东南低”的空间格局;土地利用的经济、生态环境效益整体上具有上升趋势,分别表现为“西高东低”和“中东部高西部低”的空间格局;土地利用社会效益整体上呈下降趋势,具有“中部高两翼低”的空间格局;三大效益在空间均具有较显著的聚集特征。(2)四川省各地市州的土地利用耦合协调等级为4个,总体协调水平不高,以勉强协调为主,其次是濒临失调,具有“中间高两翼低”的空间格局,且耦合等级相同的城市聚集度较高,土地利用效益耦合协调等级在空间分布上需进一步改善。(3)影响四川省地利用效益大小的因子依次为社会>经济>社会经济>社会生态>生态环境效益系统;土地利用效益耦合协调关系主要受社会、经济效益单一因子影响,其次是社会经济复合因素,最后是社会生态复合因素的影响。[结论]四川省各地市州的土地利用综合效益整体上呈上升趋势,区域差异显著,总体的耦合协调水平处于较低等级,且耦合等级相同的城市聚集度较高,在今后的发展中应该调控城镇化的无序扩张,注重城市基础公共服务等设施的建设,增加城市环境建设投入,促进四川省土地经济效益-社会效益-生态环境效益间的协调发展,以期为提升四川省土地利用综合效益提供参考。 展开更多
关键词 四川省 土地利用效益 时空耦合 地理信息系统
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