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Roshan Kumar^1,*, Wei Zhao¹, Vikash Singh²
Structural Durability & Health Monitoring, Vol.12, No.2, pp. 65-83, 2018, DOI:10.3970/sdhm.2018.02329
Abstract This paper presents an evaluation of time-frequency methods for the analysis of seismic signals. Background of the present work is to describe, how the frequency content of the signal is changing in time. The theoretical basis of short time Fourier transform, Gabor transform, wavelet transform, S-transform, Wigner distribution, Wigner-Ville distribution, Pseudo Wigner-Ville distribution, Smoothed Pseudo Wigner-Ville distribution, Choi-William distribution, Born-Jordan Distribution and cone shape distribution are presented. The strengths and weaknesses of each technique are verified by applying them to a particular synthetic seismic signal and recorded real time earthquake data. More >

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1853

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ARTICLE

Chaoyang Hu¹, Chi Ai^1,*, Fengjiao Wang^1,*
Structural Durability & Health Monitoring, Vol.12, No.2, pp. 85-98, 2018, DOI:10.3970/sdhm.2018.00115
Abstract There has been lack of work efforts on how to optimize cementing and completing parameters in order to prevent casing failure induced by formation slippage in pertroleum industry scope. Once the weak plane fails, the formation will become easily undertaken slippage across a large area along its interface. The plenty of horizontal planes of weakness in reservoir formations, as reported for a number of oilfields, can easily undertaken slippage once it fails. To address the problem, three-dimensional finite element models were established by taking into considerations the elastoplastic mechanical characteristics of both the casing and… More >

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1274

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Chengquan Wang¹, Yun Zou^1,*, Tianqi Li¹, Jie Ding¹, Xiaoping Feng¹, Tiange Lei¹
Structural Durability & Health Monitoring, Vol.12, No.2, pp. 99-110, 2018, DOI:10.3970/sdhm.2018.02061
Abstract A kind of concrete-filled lattice rectangular steel tube (CFLRST) column was put forward. The numerical simulation was modeled to analyze the mechanical characteristic of CFLRST column. By comparing the load-deformation curves from the test results, the rationality and reliability of the finite element model has been confirmed, moreover, the change of the section stiffness and stress in the forcing process and the ultimate bearing capacity of the column were analyzed. Based on the model, the comparison of ultimate bearing capacity and ductility between CFLRST column and reinforced concrete (RC) column were also analyzed. The results More >

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2091

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1408

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C. K. Madhusudana¹, N. Gangadhar¹, Hemantha Kumar, Kumar,^*,1, S. Narendranath¹
Structural Durability & Health Monitoring, Vol.12, No.2, pp. 111-127, 2018, DOI:10.3970/sdhm.2018.01262
Abstract This paper presents the fault diagnosis of face milling tool based on machine learning approach. While machining, spindle vibration signals in feed direction under healthy and faulty conditions of the milling tool are acquired. A set of discrete wavelet features is extracted from the vibration signals using discrete wavelet transform (DWT) technique. The decision tree technique is used to select significant features out of all extracted wavelet features. C-support vector classification (C-SVC) and ν-support vector classification (ν-SVC) models with different kernel functions of support vector machine (SVM) are used to study and classify the tool More >

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1633