Information entropy based algorithm of sensor placement optimization for structural damage detection

S.Q. Ye,Y. Q. Ni 국제구조공학회 2012 Smart Structures and Systems, An International Jou Vol.10 No.5

The structural health monitoring (SHM) benchmark study on optimal sensor placement problem for the instrumented Canton Tower has been launched. It follows the success of the modal identification and model updating for the Canton Tower in the previous benchmark study, and focuses on the optimal placement of vibration sensors (accelerometers) in the interest of bettering the SHM system. In this paper, the sensor placement problem for the Canton Tower and the benchmark model for this study are first detailed. Then an information entropy based sensor placement method with the purpose of damage detection is proposed and applied to the benchmark problem. The procedure that will be implemented for structural damage detection using the data obtained from the optimal sensor placement strategy is introduced and the information on structural damage is specified. The information entropy based method is applied to measure the uncertainties throughout the damage detection process with the use of the obtained data. Accordingly, a multi-objective optimal problem in terms of sensor placement is formulated. The optimal solution is determined as the one that provides equally most informative data for all objectives, and thus the data obtained is most informative for structural damage detection. To validate the effectiveness of the optimally determined sensor placement,damage detection is performed on different damage scenarios of the benchmark model using the noise-free and noise-corrupted measured information, respectively. The results show that in comparison with the existing inservice sensor deployment on the structure, the optimally determined one is capable of further enhancing the capability of damage detection.

Information entropy based algorithm of sensor placement optimization for structural damage detection

Ye, S.Q.,Ni, Y.Q. Techno-Press 2012 Smart Structures and Systems, An International Jou Vol.10 No.4

The structural health monitoring (SHM) benchmark study on optimal sensor placement problem for the instrumented Canton Tower has been launched. It follows the success of the modal identification and model updating for the Canton Tower in the previous benchmark study, and focuses on the optimal placement of vibration sensors (accelerometers) in the interest of bettering the SHM system. In this paper, the sensor placement problem for the Canton Tower and the benchmark model for this study are first detailed. Then an information entropy based sensor placement method with the purpose of damage detection is proposed and applied to the benchmark problem. The procedure that will be implemented for structural damage detection using the data obtained from the optimal sensor placement strategy is introduced and the information on structural damage is specified. The information entropy based method is applied to measure the uncertainties throughout the damage detection process with the use of the obtained data. Accordingly, a multi-objective optimal problem in terms of sensor placement is formulated. The optimal solution is determined as the one that provides equally most informative data for all objectives, and thus the data obtained is most informative for structural damage detection. To validate the effectiveness of the optimally determined sensor placement, damage detection is performed on different damage scenarios of the benchmark model using the noise-free and noise-corrupted measured information, respectively. The results show that in comparison with the existing in-service sensor deployment on the structure, the optimally determined one is capable of further enhancing the capability of damage detection.

An experimental study on constructing MR secondary suspension for high-speed trains to improve lateral ride comfort

Y.Q. Ni,S.Q. Ye,S.D. Song 국제구조공학회 2016 Smart Structures and Systems, An International Jou Vol.18 No.1

This paper presents an experimental study on constructing a tunable secondary suspension for high-speed trains using magneto-rheological fluid dampers (referred to as MR dampers hereafter), in the interest of improving lateral ride comfort. Two types of MR dampers (type-A and type-B) with different control ranges are designed and fabricated. The developed dampers are incorporated into a secondary suspension of a full-scale high-speed train carriage for rolling-vibration tests. The integrated rail vehicle runs at a series of speeds from 40 to 380 km/h and with different current inputs to the MR dampers. The dynamic performance of the two suspension systems and the ride comfort rating of the rail vehicle are evaluated using the accelerations measured during the tests. In this way, the effectiveness of the developed MR dampers for attenuating vibration is assessed. The type-A MR dampers function like a stiffness component, rather than an energy dissipative device, during the tests with different running speeds. While, the type-B MR dampers exhibit significant damping and high current input to the dampers may adversely affect the ride comfort. As part of an ongoing investigation on devising an effective MR secondary suspension for lateral vibration suppression, this preliminary study provides an insight into dynamic behavior of high-speed train secondary suspensions and unique full-scale experimental data for optimal design of MR dampers suitable for high-speed rail applications.

Elemental mercury oxidation from flue gas by microwave catalytic oxidation over Mn/g-Al2O3

Z.S. Wei,Y.W. Luo,B.R. Li,Z.Y. Chen,Q.H. Ye,Q.R. Huang,J.C. He 한국공업화학회 2015 Journal of Industrial and Engineering Chemistry Vol.24 No.-

The integrated microwave with Mn/g-Al2O3 and ozone was employed to oxidize elemental mercury (Hg0) in simulated flue gas. Hg0 oxidation efficiency in the integrated system attained 92.2%. Mn/g-Al2O3 catalyst was characterized by XRD, XPS, FT-IR, SEM. XPS spectra indicate the formation of a stable mercuric oxide species (HgO) from mercury oxidation. Ozone molecules in air could enhance free radical formation. Hg0 was oxidized to HgO in the presence of ozone and free radical. The coupling role between ozone and radical on mercury oxidation was formed. Microwave catalytic oxidation of elemental mercury reaction with the Mn/g-Al2O3 catalyst follows Langmuir–Hinshelwood kinetics.

Effect of Annealing Temperature on Soft Magnetic Properties of Cold Rolled 0.30 ㎜ Thick Fe-6.5wt.%Si Foils

X. S. Fang,J. P. Lin,Y. F. Liang,F. Ye,L. Q. Zhang,G. L. Chen 한국자기학회 2011 Journal of Magnetics Vol.16 No.2

0.30 ㎜ thick and 90 ㎜ wide thin foils made of Fe-6.5wt.%Si alloy were successfully fabricated by traditional rolling. The as-rolled sheets had good shapes and shining metal luster. The effects of annealing temperature on the magnetic properties of the sheets were investigated. Excellent Dc properties (Hc: 11.55 A/m, μm: 23710, and Bs: 1.439 T) were obtained at an annealing temperature of 1453 K for 1.5 h. At low frequencies (≤ 1 ㎑), heat treatment temperature has little effect on iron loss which remained at the level of 9.8 W/㎏. Annealing at 1273 K for 1.5 h is optimum for frequencies above 5 ㎑.

Effect of Annealing Treatment on Soft Magnetic Properties of Fe-6.5wt.% Si Thin Foils by Cold Rolling

X. S. Fang,J. P. Lin,F. Ye,L. Q. Zhang,G. L. Chen 한국자기학회 2010 한국자기학회 학술연구발표회 논문개요집 Vol.2010 No.12

An accurate substructural synthesis approach to random responses

Z.G. Ying,W.Q. Zhu,S.Q. Ye,Y.Q. Ni 국제구조공학회 2011 Structural Engineering and Mechanics, An Int'l Jou Vol.39 No.1

An accurate substructural synthesis method including random responses synthesis, frequencyresponse functions synthesis and mid-order modes synthesis is developed based on rigorous substructure description, dynamic condensation and coupling. An entire structure can firstly be divided into several substructures according to different functions, geometric and dynamic characteristics. Substructural displacements are expressed exactly by retained mid-order fixed-interfacial normal modes and residual constraint modes. Substructural interfacial degree-of-freedoms are eliminated by interfacial displacements compatibility and forces equilibrium between adjacent substructures. Then substructural mode vibration equations are coupled to form an exact-condensed synthesized structure equation, from which structural mid-order modes are calculated accurately. Furthermore, substructural frequency-response function equations are coupled to yield an exact-condensed synthesized structure vibration equation in frequency domain, from which the generalized structural frequency-response functions are obtained. Substructural frequency-response functions are calculated separately by using the generalized frequency-response functions, which can be assembled into an entire-structural frequency-response function matrix. Substructural power spectral density functions are expressed by the exact-synthesized substructural frequency-response functions, and substructural random responses such as correlation functions and meansquare responses can be calculated separately. The accuracy and capacity of the proposed substructure synthesis method is verified by numerical examples.

An accurate substructural synthesis approach to random responses

Ying, Z.G.,Zhu, W.Q.,Ye, S.Q.,Ni, Y.Q. Techno-Press 2011 Structural Engineering and Mechanics, An Int'l Jou Vol.39 No.1

An accurate substructural synthesis method including random responses synthesis, frequency-response functions synthesis and mid-order modes synthesis is developed based on rigorous substructure description, dynamic condensation and coupling. An entire structure can firstly be divided into several substructures according to different functions, geometric and dynamic characteristics. Substructural displacements are expressed exactly by retained mid-order fixed-interfacial normal modes and residual constraint modes. Substructural interfacial degree-of-freedoms are eliminated by interfacial displacements compatibility and forces equilibrium between adjacent substructures. Then substructural mode vibration equations are coupled to form an exact-condensed synthesized structure equation, from which structural mid-order modes are calculated accurately. Furthermore, substructural frequency-response function equations are coupled to yield an exact-condensed synthesized structure vibration equation in frequency domain, from which the generalized structural frequency-response functions are obtained. Substructural frequency-response functions are calculated separately by using the generalized frequency-response functions, which can be assembled into an entire-structural frequency-response function matrix. Substructural power spectral density functions are expressed by the exact-synthesized substructural frequency-response functions, and substructural random responses such as correlation functions and mean-square responses can be calculated separately. The accuracy and capacity of the proposed substructure synthesis method is verified by numerical examples.

Cyclin D1-positive diffuse large B-cell lymphoma

Rodriguez-Justo, M,Huang, Y,Ye, H,Liu, H,Chuang, S-S,Munson, P,Prada-Puentes, C,Kim, I,Du, M-Q,Bacon, C M Blackwell Publishing Ltd 2008 Histopathology Vol.52 No.7

Upgrade of X-ray crystal spectrometer for high temperature measurement using neon-like xenon lines on EAST

Hu, R. J.,Chen, J.,Delgado-Aparicio, L. F.,Wang, Q. P.,Du, X. W.,Shen, J.,Yang, X. S.,Wang, F. D.,Fu, J.,Li, Y. Y.,Bitter, M.,Hill, K. W.,Pablant, N. A.,Lee, S. G.,Shi, Y. J.,Wan, B. N.,Ye, M. Y.,Lyu, American Institute of Physics 2018 Review of scientific instruments Vol.89 No.10