A diagnosis method for slab bridge bearing failure based on vibration mode parameters

2021 ◽  
Author(s):  
Qin Xuxi ◽  
Qin Weijun ◽  
Ding Kai
Keyword(s):  
Vibration Mode ◽  
Bearing Failure ◽  
Diagnosis Method ◽  
Bridge Bearing

New Method Using Piezoelectric Jerk Sensor to Detect Roller Bearing Failure

2013 ◽  
Vol 7 (5) ◽  
pp. 550-557 ◽  
Author(s):  
Nobuhiko Henmi ◽  
◽  
Shingo Takeuchi
Keyword(s):  
Rotation Speed ◽  
Roller Bearing ◽  
New Method ◽  
Bearing Failure ◽  
Acceleration Sensor ◽  
Damage Diagnosis ◽  
Vibration Detection ◽  
Diagnosis Method ◽  
Bearing Damage ◽  
Conical Roller

An acceleration sensor is usually used to examine for roller bearing damage. It is difficult, however, to detect abnormal vibration and examine for roller bearing damage when rotation speed is low. The final target of this study is to establish a bearing damage diagnosis system based on the piezoelectric jerk sensor we developed, which can be used for both low- and highspeed rotations. For this purpose, this paper aims to identify the features of an abnormal vibration detection signal at a low rotation speed, propose a new roller bearing damage diagnosis method that uses the features, and clarify the validity of the method. Experiments are conducted to analyze a scratch purposely made on the outer ring of a conical roller bearing that rotates at the low speeds of 10 or 40 rpm. The results verify the advantages of using the jerk sensor for the bearing damage diagnosis and the validity of the method proposed in this paper.

A heterogeneous fault diagnosis method for bearings in gearbox

2014 ◽  
Vol 229 (8) ◽  
pp. 1491-1499 ◽  
Author(s):  
Xiaohui Chen ◽  
Lei Xiao ◽  
Xinghui Zhang ◽  
Zhenxiang Liu
Keyword(s):  
Fault Diagnosis ◽  
Bearing Failure ◽  
Optimum Frequency ◽  
Bearing Faults ◽  
Outer Race ◽  
Bearing Fault ◽  
Spectral Kurtosis ◽  
Bearing Fault Diagnosis ◽  
Diagnosis Method ◽  
Inner Race

Bearing failure is one of the most important causes of breakdown of rotating machinery. These failures can lead to catastrophic disasters or result in costly downtime. One of the key problems in bearing fault diagnosis is to detect the bearing fault as early as possible. This capability enables the operator to have enough time to do some preventive maintenance. Most papers investigate the bearing faults under rational assumption that bearings work individually. However, bearings are usually working as a part of complex systems like a gearbox. The fault signal of bearings can be easily masked by other vibration generated from gears and shafts. The proposed method separates bearing signals from other signals, and then the optimum frequency band which the bearing fault signal is prominent is determined by mean envelope Kurtosis. Subsequently, the envelope analysis is used to detect the bearing faults. Finally, two bearing fault experiments are used to validate the proposed method. Each experiment contains two bearing fault modes, inner race fault and outer race fault. The results demonstrate that the proposed method can detect the bearing fault easier than spectral Kurtosis and envelope Kurtosis.

Distribution of c-protein isoforms in sarcomeres of developing chick skeletal muscle

1988 ◽  
Vol 46 ◽  
pp. 226-227
Author(s):  
D. A. Fischman ◽  
J. E. Dennis ◽  
T. Obinata ◽  
H. Takano-Ohmuro
Keyword(s):  
Skeletal Muscles ◽  
Thick Filament ◽  
Protein Isoforms ◽  
Actin Binding ◽  
Striated Muscles ◽  
C Protein ◽  
Sarcomeric Protein ◽  
Thick Filaments ◽  
Cross Bridges ◽  
Bridge Bearing

C-protein is a 150 kDa protein found within the A bands of all vertebrate cross-striated muscles. By immunoelectron microscopy, it has been demonstrated that C-protein is distributed along a series of 7-9 transverse stripes in the medial, cross-bridge bearing zone of each A band. This zone is now termed the C-zone of the sarcomere. Interest in this protein has been sparked by its striking distribution in the sarcomere: the transverse repeat between C-protein stripes is 43 nm, almost exactly 3 times the 14.3 nm axial repeat of myosin cross-bridges along the thick filaments. The precise packing of C-protein in the thick filament is still unknown. It is the only sarcomeric protein which binds to both myosin and actin, and the actin-binding is Ca-sensitive. In cardiac and slow, but not fast, skeletal muscles C-protein is phosphorylated. Amino acid composition suggests a protein of little or no αhelical content. Variant forms (isoforms) of C-protein have been identified in cardiac, slow and embryonic muscles.

Helicopter main reduction planetary gear fault diagnosis method based on SVDD

2020 ◽  
Vol 64 (1-4) ◽  
pp. 137-145
Author(s):  
Yubin Xia ◽  
Dakai Liang ◽  
Guo Zheng ◽  
Jingling Wang ◽  
Jie Zeng
Keyword(s):  
Fault Diagnosis ◽  
Planetary Gear ◽  
Gaussian Kernel ◽  
Support Vector ◽  
Support Vector Data Description ◽  
Vector Data ◽  
Energy Characteristics ◽  
Gear Fault ◽  
Channel Information ◽  
Diagnosis Method

Aiming at the irregularity of the fault characteristics of the helicopter main reducer planetary gear, a fault diagnosis method based on support vector data description (SVDD) is proposed. The working condition of the helicopter is complex and changeable, and the fault characteristics of the planetary gear also show irregularity with the change of working conditions. It is impossible to diagnose the fault by the regularity of a single fault feature; so a method of SVDD based on Gaussian kernel function is used. By connecting the energy characteristics and fault characteristics of the helicopter main reducer running state signal and performing vector quantization, the planetary gear of the helicopter main reducer is characterized, and simultaneously couple the multi-channel information, which can accurately characterize the operational state of the planetary gear’s state.

Diagnosis Method of Aging Degradation for Insulating Paper using Small Amount of Cellulose Fibers

2019 ◽  
Vol 139 (2) ◽  
pp. 130-135
Author(s):  
Masanobu Yoshida ◽  
Yoshinori Konishi ◽  
Masamichi Kato
Keyword(s):  
Cellulose Fibers ◽  
Insulating Paper ◽  
Diagnosis Method

Our Surgical Strategy for Thoracic Outlet Syndrome

2018 ◽  
Vol 1 (2) ◽  
Author(s):  
Yasuhiro Nakajima
Keyword(s):  
Brachial Plexus ◽  
Thoracic Outlet Syndrome ◽  
Vascular Compression ◽  
Compression Tests ◽  
Provocation Tests ◽  
Diagnosis Method ◽  
Tunnel Syndrome ◽  
Electrophysiological Examination ◽  
Sensory Neural ◽  
Plexus Block

Surgical treatment for thoracic outlet syndrome (TOS) is a very controversial surgery because objective diagnosis, such as image and electrophysiological examination, is very difficult. Clinical provocation tests including brachial plexus compression tests, such as Morley and Roos, and vascular compression tests, such as Wright and Eden ,are not high in specificity and are likely to be positive even in healthy persons and patients with carpal tunnel syndrome. We place emphasis on the laterality of latency and amplitude in the sensory neural action potential (SNAP) of the medial antebrachial cutaneous nerve and ulnar nerve. After enough stretching exercises of scapular stabilizers and brachial plexus block, we always select surgery. In this presentation, I would like to show our diagnosis method and treatment strategy including surgery.

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