• Title/Summary/Keyword: identification experiment

Search Result 763, Processing Time 0.045 seconds

Experiment study of structural random loading identification by the inverse pseudo excitation method

  • Guo, Xing-Lin;Li, Dong-Sheng
    • Structural Engineering and Mechanics
    • /
    • v.18 no.6
    • /
    • pp.791-806
    • /
    • 2004
  • The inverse pseudo excitation method is used in the identification of random loadings. For structures subjected to stationary random excitations, the power spectral density matrices of such loadings are identified experimentally. The identification is based on the measured acceleration responses and the structural frequency response functions. Numerical simulation is used in the optimal selection of sensor locations. The proposed method has been successfully applied to the loading identification experiments of three structural models, two uniform steel cantilever beams and a four-story plastic glass frame, subjected to uncorrelated or partially correlated random excitations. The identified loadings agree quite well with actual excitations. It is proved that the proposed method is quite accurate and efficient in addition to its ability to alleviate the ill conditioning of the structural frequency response functions.

Experimental Verification of Damage Identification Method using Moving load Response (이동하중응답을 이용한 손상인식기법의 실험적 검증)

  • Choi, Sang-Hyun;Kim, Dae-Hyork
    • Proceedings of the KSR Conference
    • /
    • 2009.05a
    • /
    • pp.552-559
    • /
    • 2009
  • Most damage identification methods for structural health monitoring developed to date utilize modal domain responses which require postprocessing and inevitably contain errors in transforming the domain of responses. In this paper, the feasibility of a damage identification method based on dynamics responses from moving loads is experimentally verified. The experiment is performed via applying periodic and non-periodic moving loads to a steel beam and acceleration and displacement responses of the beam is measured. The moving loads is applied using steel balls and the damage of a structure is simulated by saw-cutting the beam. The damage identification results using the measured responses show that the moving load response based damage identification method successfully identify all damages in the beam.

  • PDF

Semantic Similarity-Based Contributable Task Identification for New Participating Developers

  • Kim, Jungil;Choi, Geunho;Lee, Eunjoo
    • Journal of information and communication convergence engineering
    • /
    • v.16 no.4
    • /
    • pp.228-234
    • /
    • 2018
  • In software development, the quality of a product often depends on whether its developers can rapidly find and contribute to the proper tasks. Currently, the word data of projects to which newcomers have previously contributed are mainly utilized to find appropriate source files in an ongoing project. However, because of the vocabulary gap between software projects, the accuracy of source file identification based on information retrieval is not guaranteed. In this paper, we propose a novel source file identification method to reduce the vocabulary gap between software projects. The proposed method employs DBPedia Spotlight to identify proper source files based on semantic similarity between source files of software projects. In an experiment based on the Spring Framework project, we evaluate the accuracy of the proposed method in the identification of contributable source files. The experimental results show that the proposed approach can achieve better accuracy than the existing method based on comparison of word vocabularies.

Experimental Study of System Identification for Seismic Response of Building Structure (건축구조물의 지진응답제어를 위한 시스템 식별의 실험적 연구)

  • 주석준;박지훈;민경원;홍성목
    • Journal of the Earthquake Engineering Society of Korea
    • /
    • v.3 no.4
    • /
    • pp.47-60
    • /
    • 1999
  • The stability and efficiency of structural control systems depend on the accuracy of mathematical model of the system to be controlled. In this study, state equation models of a small scale test structure and an AMD(active mass damper) are obtained separately using OKID(observer/Kalman filter identification) which is a time domain system identification method. The test structure with each floor acceleration as outputs is identified for two inputs - the ground acceleration and the acceleration of the moving mass of AMD relative to the installation floor - individually and the two identified state equation models are integrated into one by model reduction method. The AMD is identified with the motor control signal as an input and the relative acceleration of the moving mass as an output, and it is shown that the identified model has large damping ratio and phase shift. The transfer functions and the time histories reconstructed from the identified models of the test model and the AMD match well with those measured from the experiment.

  • PDF

A Detection Method of Fake Fingerprint in Optical Fingerprint Sensor (광학식 지문센서에서의 위조 지문 검출 방법)

  • Lee, Ji-Sun;Kim, Jae-Hwan;Chae, Jin-Seok;Lee, Byoung-Soo
    • Journal of Korea Multimedia Society
    • /
    • v.11 no.4
    • /
    • pp.492-503
    • /
    • 2008
  • With the recent development and increasing importance of personal identification systems, biometric technologies with less risk of loss or unauthorized use are being popularized rapidly. In particular, because of their high identification rate and convenience, fingerprint identification systems are being used much more commonly than other biometric systems such as iris recognition, face recognition and vein pattern recognition. However, a fingerprint identification system has the problem that artificially forged finger-prints can be used as input data. Thus, in order to solve this problem, the present study proposed a method for detecting forged fingerprints by measuring the degree of attenuation when the light from an optical fingerprint sensor passes through the finger and analyzing changes in the transmission of light over stages at fixed intervals. In order to prove improvement in the performance of the proposed system, we conducted an experiment that compared the system with an existing multi-sensor recognition system that measures also the temperature of fingerprint. According to the results of the experiment, the proposed system improved the forged fingerprint detection rate by around 32.6% and this suggests the possibility of solving the security problem in fingerprint identification systems.

  • PDF

Improvement on Performance Simulation Using Component Maps of Aircraft Gas Turbine Obtained from System Identification (시스템 식별로 구한 구성품 성능선도를 이용한 개선된 가스터빈 성능해석 연구)

  • Kong, Chang-Duk;Kho, Seong-Hee;Ki, Ja-Young
    • Journal of the Korean Society for Aeronautical & Space Sciences
    • /
    • v.32 no.6
    • /
    • pp.96-103
    • /
    • 2004
  • Sought a set of component performance lines from experiment data or some data supplied in the engine manufacturer to improve the traditional scaling method and suggested a map scaling method that construct component performance lines newly using polynomial equations of MATLAB program. In this study, applied technique that is proposed newly to PT6A-62 that verified technique that is proposed newly using experiment data of small. size turboshaft engine, and is actuality aircraft engine. In identification of the component maps of the turboprop engine, the simulated performance using the proposed scaling method was compared with the real engine performance data and the performance using the traditional scaling method.

A Study on the Fundamental Experiment on the Sea for the Construction of Ubiquitous Aids to Navigation (유비쿼터스 해상안전표지시설 구축을 위한 해상기초실험에 관한 연구)

  • Gug Seung-Gi;Kim Jung-Hoon;Kim Min-Cheol
    • Journal of Navigation and Port Research
    • /
    • v.30 no.3 s.109
    • /
    • pp.197-201
    • /
    • 2006
  • The AIS(Automatic Identification System) is the useful equipment in order to promote the maritime safety and real time monitoring at the sea. In this study, the plan to construct the ubiquitous Aids to navigation is proposed. In order to verify the construction of ubiquitous Aids to navigation, the experiment on the sea was carried out and analyzed.