Development of a high-speed spectroscopic imaging system over a wide frequency range with THz-TDS

The presented paper describes the investigation of vibro-isolating features of transmissions of vehicles using universal dynamic test stand. The stand is protected by copyright and distinguishes itself for many advantages in comparison with the existing stands: it is contactless, precise in a wide frequency range, power-saving, high-speed. Due to low exploitation expenses and wide possibilities it is fit for the investigation of dynamic characteristics of various vehicles. On the said stand using the method of the identification of experiment dynamic processes, the investigation of vibroisolating features of rotor systems has been performed. The errors caused by the unevenness of rotation of connecting shafts, the adequacy of the calculated models and the dangerous resonance frequencies have been determined.

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A Tuned Mass Damper with Nonlinear Magnetic Force for Vibration Suppression with Wide Frequency Range of Offshore Platform under Earthquake Loads

Shock and Vibration ◽

10.1155/2018/1505061 ◽

2018 ◽

Vol 2018 ◽

pp. 1-18 ◽

Cited By ~ 2

Author(s):

Qiong Wu ◽

Wei Zhao ◽

Weiguo Zhu ◽

Rencheng Zheng ◽

Xilu Zhao

Keyword(s):

High Speed ◽

Permanent Magnets ◽

Vibration Suppression ◽

Wide Frequency Range ◽

Offshore Platform ◽

Offshore Platforms ◽

Frequency Range ◽

Response Characteristics ◽

Narrow Frequency Band ◽

Dynamic Performances

Tuned mass dampers (TMDs) are applied to ensure the safety and stability of offshore platforms; however, linear dampers are effective for a single resonance frequency, providing vibration suppression only within a narrow frequency band. Therefore, this paper proposed a magnetic TMD with two pairs of permanent magnets on both sides of the structures, which can generate a nonlinearly repulsive force, making the magnetic TMD reliable and robust in damping the oscillations of structures with wide frequency range under seismic excitations. A comprehensively numerical and experimental study was processed to investigate the dynamic performances of the proposed magnetic TMD, by application of a 1 : 200-scale prototype of the offshore platform. The results verified that the performance of the magnetic TMD can be significantly improved than that of the linear TMD, meanwhile maintaining high-speed response characteristics. The experimental results indicated that the displacement, acceleration, and frequency responses of the offshore platform can be significantly reduced; furthermore, the evaluation indices showed that the magnetic TMD system is credible in reducing the overall vibration levels and maximum peak values.

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A High-Speed and Stable THz Spectroscopic Imaging System Using Multiwavelength is- Tpg

2018 43rd International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz) ◽

10.1109/irmmw-thz.2018.8510124 ◽

2018 ◽

Author(s):

Kosuke Murate ◽

Kazuki Maeda ◽

Yunzhuo Guc ◽

Kodo Kawase

Keyword(s):

High Speed ◽

Imaging System ◽

Spectroscopic Imaging

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Application of a Spectroscopic Infrared Focal Plane Array Sensor for On-Line Identification of Plastic Waste

Applied Spectroscopy ◽

10.1366/0003702971941142 ◽

1997 ◽

Vol 51 (6) ◽

pp. 856-865 ◽

Cited By ~ 25

Author(s):

W. H. A. M. Van Den Broek ◽

D. Wienke ◽

W. J. Melssen ◽

R. Feldhoff ◽

T. Huth-Fehre ◽

...

Keyword(s):

Focal Plane ◽

High Speed ◽

Supervised Classification ◽

Imaging System ◽

Spectroscopic Imaging ◽

Focal Plane Array ◽

Array Detector ◽

Identification System ◽

Linear Discriminant ◽

On Line

A spectroscopic near-infrared imaging system, using a focal plane array (FPA) detector, is presented for remote and on-line measurements on a macroscopic scale. On-line spectroscopic imaging requires high-speed sensors and short image processing steps. Therefore, the use of a focal plane array detector in combination with fast chemometric software is investigated. As these new spectroscopic imaging systems generate so much data, multivariate statistical techniques are needed to extract the important information from the multidimensional spectroscopic images. These techniques include principal component analysis (PCA) and linear discriminant analysis (LDA) for supervised classification of spectroscopic image data. Supervised classification is a tedious task in spectroscopic imaging, but a procedure is presented to facilitate this task and to provide more insight into and control over the composition of the datasets. The identification system is constructed, implemented, and tested for a real-world application of plastic identification in municipal solid waste.

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