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Model updating for real time dynamic substructures based on UKF algorithm

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Earthquake Engineering and Engineering Vibration 2020年第2期19卷 413-421页

作者： Su Tingli Tang Zhenyun Peng Lingyun Bai Yuting Jin Xuebo Kong Jianlei School of Computer Information and Engineering Beijing Technology and Business UniversityBeijing 100048China The Key Laboratory of Urban Security and Disaster Engineering Ministry of EducationBeijing University of TechnologyBeijing 100124China Beijing Key Laboratory of Big Data Technology for Food Safety Beijing Technology and Business UniversityBeijing 100048China China Light Industry Key Laboratory of Industrial Internet and Big Data Beijing Technology and Business UniversityBeijing 100048China

Combining the advantages of numerical simulation with experimental testing,real-time dynamic substructure(RTDS)testing provides a new experimental method for the investigation of engineered ***,not all unmodeled parts can be physically tested,as testing is often limited by the capacity of the test *** updating is a good option to improve the modeling accuracy for numerical substructures in *** this study,a model updating method is introduced,which has great performance in describing this *** order to determine the optimal parameters in this model,an Unscented Kalman Filter(UKF)-based algorithm was applied to extract the knowledge contained in the sensors *** the parameters that need to be identified are listed as the extended state variables,and the identification was achieved via the step-by-step state prediction and state update *** of the proposed method was verified through a group of experimental data,and results showed good ***,the proposed method was compared with the Extended Kalman Filter(EKF)-based method,and better accuracy was easily *** proposed parameter identification method has great applicability for structural objects with nonlinear behaviors and could be extended to research in other engineering fields.

关键词： dynamic substructure complex nonlinear model nonlinear estimation adaptive updating civil infrastructures

Integral ear elimination and virtual point-based updating algorithms for constrained Delaunay TIN

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Science China(Technological Sciences) 2008年第S1期51卷 135-144页

作者： WU LiXin1,2,WANG YanBing2,3 & SHI WenZhong2,4 1 Institute for Geo-informatics & Digital Mine Research,Northeastern University,Shenyang 110004,China 2 Institute for GIS/RS/GPS & Subsidence Engineering Research,China University of Mining & Technology,Beijing 100085,China 3 Laboratory of 3D Information Acquisition & Application,Capital Normal University,Beijing 100037,China 4 Center for Advanced GIS Research,LSGI,Polytechnic University Hong Kong,Hong Kong,China Institute for Geo-informatics & Digital Mine Research Northeastern University Shenyang China Institute for GIS/RS/GPS & Subsidence Engineering Research China University of Mining & Technology Beijing China Laboratory of 3D Information Acquisition & Application Capital Normal University Beijing China Center for Advanced GIS Research LSGI Polytechnic University Hong Kong Hong Kong China

Constrained Delaunay Triangular Irregular Networks (CD-TIN),a kind of special data structure,have many practical applications in Geoinformatics,especially in the representation of linear constrained triangulation for DTM and DSM,such as in digital city and digital mine. Past researches on D-TIN mainly focused on point in-sertion and deletion without consideration of constraint,and that on CD-TIN usu-ally paid more attention to the insertion algorithms for points and edges,but little to the deletion algorithms. The presented algorithms are far insufficient for the dy-namic updating of CD-TIN. In this paper,the constraint edge in CD-TIN is consid-ered to be any set of broken lines,i.e.,polygon edges,broken lines and simple segments. The constraint edge may be composed of one or more constraint seg-ments,and it is allowed to be in any form: Open or close,intersection or self-in-tersection. By improving to present insertion and deletion algorithms for D-TIN,two new algorithms for CD-TIN updating are presented. According to the polymorphism of the constraints in CD-TIN,virtual point is adopted to represent the crossing node between constraint edges when a constraint edge is inserted in CD-TIN. Two new algorithms named as Integral Ear Elimination (IEE) and Influence Domain Retrian-gulation for Virtual Point (IDRVP) are presented,the former is for constraint point deletion,while the later is for the insertion and deletion of constraint edge. The principle of IDRVP is that to divide the influence domain of a virtual point into some parts by the constraint-keeping edges,and to retriangulate each part of the influ-ence domain individually referring to the constraint visible property and constraint empty circle (CEC) criterion. Finally,a prototype system is developed with VC++,one case on the integration of 3D terrain and buildings is demonstrated to test the correctness of new algorithms. It shows that the new algorithms are effective for the updating of CD-TIN.

关键词： Delaunay TIN spatial constraint data updating spatial modeling polymorphism digital mine

An event-driven dynamic updating method for 3D geo-databases

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Geo-Spatial Information Science 2016年第2期19卷中插5-中插5,140-147页

作者： Han Guo Weixi Wang Zhihan Lv Chen Wu Weiping Xu Shenzhen Research Center of Digital City Engineering ShenzhenChina Key Laboratory of Urban Land Resources Monitoring and Simulation Ministry of Land and ResourcesShenzhenChina Shenzhen Institutes of Advanced Technology Chinese Academy of SciencesShenzhenChina State Key Laboratory of Information Engineering in Surveying Mapping and Remote SensingWuhan UniversityWuhanChina

With the rapid development of 3D Digital City, the focus of research has shifted from 3D city modeling and geo-database construction to 3D geo-database service and maintenance. The frequent modifications on geometry, texture, attribute, and topology present a great challenge to the 3D geo-database *** article proposes an event-driven spatiotemporal database model (ESDM) that combines the historical and present 3D city models with the semantic classification and state expression, triggered by changing events predefined. In addition, a corresponding dynamic updating method based on adaptive matching algorithm is presented to perform the dynamic updating operation for the complex 3D city models automatically, according to the compound matching of semantics, attributes, and spatial locations. finally, the validity and feasibility of the proposed ESDM and its updating method are demonstrated through a 3D geo-database with more than 1.5 million 3D city models.

关键词： Dynamic updating 3D geo-database semantic event-driven adaptive matching

Employing incomplete complex modes for model updating and damage detection of damped structures

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Science China(Technological Sciences) 2008年第12期51卷 2244-2258页

作者： HU Sau-Lon James Department of Ocean Engineering University of Rhode Island

In the study of finite element model updating or damage detection,most papers are devoted to undamped ***,their objective has been exclusively restricted to the correction of the mass and stiffness *** contrast,this paper performs the model updating and damage detection for damped structures.A theoretical contribution of this paper is to extend the cross-model cross-mode(CMCM) method to simultaneously update the mass,damping and stiffness matrices of a finite element model when only few spatially incomplete,complex-valued modes are *** studies are conducted for a 30-DOF(degree-of-freedom) cantilever beam with multiple damaged elements,as the measured modes are synthesized from finite element *** numerical results reveal that applying the CMCM method,together with an iterative Guyan reduction scheme,can yield good damage detection in *** the measured modes utilized in the CMCM method are corrupted with irregular errors,assessing damage at the location that possesses larger modal strain energy is less sensitive to the corrupted modes.

关键词： incomplete complex modes model updating damage detection CMCM damped structures

Cooperative Spectrum Sensing in Cognitive Radio Using Bayesian updating with Multiple Observations

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Journal of Electronic Science and Technology 2019年第3期17卷 252-259页

作者： Yung-Fa Huang Jyu-Wei Wang the Department of Information and Communication Engineering Chaoyang University of TechnologyTaichung 41368 the Department of Photonics and Communication Engineering Asia UniversityTaichung 41354

We study cooperative spectrum sensing in cognitive radio (CR) networks using the hidden Markov model (HMM) for opportunistic spectrum access (OSA). We assume that the primary channel operates in a time division multiple address (TDMA) manner. Thus, spectrum sensing is operating in a slot-by-slot basis. In contrast to the conventional Bayesian updating using only one observation, in this work, we propose to perform the update in a concatenated fashion with all the observations available from the secondary users (SUs). In the proposed scheme, a predefined threshold on the belief is used for determining the channel activity. With the threshold, the proposed scheme is more flexible in the system operation than the simple majority vote scheme, in which no such threshold is available. We compare, by simulations, the performance of the proposed concatenated update scheme with that of the majority vote scheme and show that the probabilities of correctly detecting a busy state and an idle state are about 1 as the number of SUs is as large as 15, so the effects of the further increase in the number of SUs are limited.

关键词： Bayesian updating cognitive radio(CR) cooperative sensing hidden Markov model(HMM)

Transient content caching and updating with modified harmony search for Internet of Things

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Digital Communications and Networks 2019年第1期5卷 24-33页

作者： Chao Xu Xijun Wang Key Laboratory of Agricultural Internet of Things Ministry of Agriculuture and Rural Affairs School of Information Engineering Northwest A&F University Yangling Shaanxi China School of Electronics and Communication Engineering Sun Yat-sen University Guangzhou China

Internet of Things (IoT) has emerged as one of the new use cases in the 5th Generation wireless networks. However, the transient nature of the data generated in IoT networks brings great challenges for content caching. In this paper, we study a joint content caching and updating strategy in IoT networks, taking both the energy consumption of the sensors and the freshness loss of the contents into account. In particular, we decide whether or not to cache the transient data and, if so, how often the servers should update their contents. We formulate this content caching and updating problem as a mixed 0–1 integer non-convex optimization programming, and devise a Harmony Search based content Caching and updating (HSCU) algorithm, which is self-learning and derivativefree and hence stipulates no requirement on the relationship between the objective and variables. Finally, extensive simulation results verify the effectiveness of our proposed algorithm in terms of the achieved satisfaction ratio for content delivery, normalized energy consumption, and overall network utility, by comparing it with some baseline algorithms.

关键词： IoT Content caching and updating Data freshness

Dynamic Fault Diagnosis Using the Improved Linear Evidence updating Strategy

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Journal of Shanghai Jiaotong university(Science) 2015年第4期20卷 427-436页

作者：尚群立张镇徐晓滨 College of Information Engineering Zhejiang University of Technology Institute of Systems Science and Control Engineering Hangzhou Dianzi University

The majority of the existing fault diagnosis methods using Dempster-Shafer(DS) evidence theory(DST) all provide the "static" fused results by combining several pieces of diagnosis evidence, which only reflect the current running status of monitored equipment. This paper presents the dynamic diagnosis strategy by using recursively the improved linear evidence updating rule. Its updated result can synthesize the diagnosis evidence collected at historical, current and future time steps by dynamically adjusting the proposed smoothing linear combination weights. The diagnosis examples of machine rotor show that the proposed method can provide more reliable and accurate results than the diagnosis methods based on the classical updating strategies.

关键词： dynamic fault diagnosis information fusion Dempster-Shafer evidence theory(DST) evidence updating

Automatic Road Change Detection and GIS updating from High Spatial Remotely-Sensed Imagery

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Geo-Spatial Information Science 2004年第2期7卷 89-95,107页

作者： ZHANGQiaoping IsabelleCouloigner DepartmentofGeomaticsEngineering TheUniversityofCalgaryCalgaryAlbertaCanada 不详

This paper presents a framework for road network change detection in order to update the Canadian National Topographic DataBase (NTDB). The methodology has been developed on the basis of road extraction from IRS\|pan images (with a 5.8 m spatial resolution) by using a wavelet approach. The feature matching and conflation techniques are used to road change detection and updating. Elementary experiments have showed that the proposed framework could be used for developing an operational road database updating system.

关键词： road extraction change detection updating feature matching conflation

Finite Element Model updating of Complicated Beam-Type Structures Based on Reduced Super Beam Model

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Journal of Harbin Institute of Technology(New Series) 2019年第3期26卷 68-78页

作者： Wensheng Wang Haojie Wei Zhonghua Hou Qun Mei Yifan Li Department of Engineering Mechanics Henan University of Science and Technology

A finite element model updating technique for complicated beam-type structures is presented in this ***, a complicated beam-type structure is reduced to a reduced super beam model with a much smaller degree of freedom by using the reduced super beam method, which is based on the classic plane cross-section assumption and displacement interpolation function of beam *** based on the reduced super beam, the analysis of eigensolutions and eigensensitivities from the reduced eigenequation are processed for model updating, which will greatly reduce the computational effort when compared to the traditional model updating methods performed on the global *** techniques are adopted for updating the difference of modal dynamic properties, resulting in optimal values of the structural ***, a complicated stiffened cylindrical shell model and a practical missile structure, served as the illustrative examples, are employed for model updating application, which demonstrate that the reduced super beam-based method is both effective and highly efficient.

关键词： reduced super beam method model updating complicated beam-type structures eigensolution eigensensitivity