scholarly journals Design And Fabrication Of Impact (Acceleration) Sensors As Class Projects In A Mems Course

2020 ◽  
Author(s):  
Mustafa Guvench
Keyword(s):  
Acceleration Sensors ◽  
Impact Acceleration

scholarly journals The Adverse Pial Arteriolar and Axonal Consequences of Traumatic Brain Injury Complicated by Hypoxia and Their Therapeutic Modulation with Hypothermia in Rat

2009 ◽  
Vol 30 (3) ◽  
pp. 628-637 ◽  
Author(s):  
Guoyi Gao ◽  
Yasutaka Oda ◽  
Enoch P Wei ◽  
John T Povlishock
Keyword(s):  
Traumatic Brain Injury ◽  
Brain Injury ◽  
Amyloid Precursor Protein ◽  
Vascular Reactivity ◽  
Axonal Damage ◽  
Precursor Protein ◽  
Moderate Hypothermia ◽  
Vascular Protection ◽  
Impact Acceleration ◽  
Cerebral Vascular

This study examined the effect of posttraumatic hypoxia on cerebral vascular responsivity and axonal damage, while also exploring hypothermia's potential to attenuate these responses. Rats were subjected to impact acceleration injury (IAI) and equipped with cranial windows to assess vascular reactivity to topical acetylcholine, with postmortem analyses using antibodies to amyloid precursor protein to assess axonal damage. Animals were subjected to hypoxia alone, IAI and hypoxia, IAI and hypoxia before induction of moderate hypothermia (33°C), IAI and hypoxia induced during hypothermic intervention, and IAI and hypoxia initiated after hypothermia. Hypoxia alone had no impact on vascular reactivity or axonal damage. Acceleration injury and posttraumatic hypoxia resulted in dramatic axonal damage and altered vascular reactivity. When IAI and hypoxia were followed by hypothermic intervention, no axonal or vascular protection ensued. However, when IAI was followed by hypoxia induced during hypothermia, axonal and vascular protection followed. When this same hypoxic insult followed the use of hypothermia, no benefit ensued. These studies show that early hypoxia and delayed hypoxia exert damaging axonal and vascular consequences. Although this damage is attenuated by hypothermia, this follows only when hypoxia occurs during hypothermia, with no benefit found if the hypoxic insult proceeds or follows hypothermia.

scholarly journals Acute Effects on Impact Accelerations Running with Objects in the Hand

Life ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 550
Author(s):  
Roberto Sanchis-Sanchis ◽  
Alberto Encarnación-Martínez ◽  
Jose I. Priego-Quesada ◽  
Inmaculada Aparicio ◽  
Irene Jimenez-Perez ◽  
...  
Keyword(s):  
Mobile Phone ◽  
Step Length ◽  
Stride Frequency ◽  
Acute Effects ◽  
Shock Attenuation ◽  
Acceleration Rate ◽  
Recreational Runners ◽  
Impact Acceleration ◽  
Spatio Temporal ◽  
Extra Weight

Amateur runners usually run carrying implements in their hands (keys, a mobile phone, or a bottle of water). However, there is a lack of literature about the effects of different handloads on impact accelerations. Thus, this study aimed to analyse the effects of carrying different objects in the hand on impact accelerations during running. Nineteen male recreational runners (age 24.3 ± 6.8 years, training volume of 25 ± 7.38 km/week) performed twenty minutes of running on a treadmill at 2.78 m/s with four different conditions: no extra weight, with keys, with a mobile phone, and with a bottle of water. Impact acceleration and spatio-temporal parameters were analysed through a wireless triaxial accelerometry system composed of three accelerometers: two placed in each tibia and one placed on the forehead. A higher tibia acceleration rate in the dominant leg was observed when participants ran holding both a mobile phone (p = 0.027; ES = 0.359) and a bottle of water (p = 0.027; ES = 0.359), compared to no extra weight. No changes were observed in peak acceleration, acceleration magnitude, and shock attenuation in any other conditions. Likewise, neither stride frequency nor step length was modified. Our results suggest that recreational runners should not worry about carrying objects in their hands, like a mobile phone or a bottle of water, in short races because their effect seems minimal.

scholarly journals A Fusion Feature Extraction Method Using EEMD and Correlation Coefficient Analysis for Bearing Fault Diagnosis

2018 ◽  
Vol 8 (9) ◽  
pp. 1621 ◽  
Author(s):  
Fan Jiang ◽  
Zhencai Zhu ◽  
Wei Li ◽  
Yong Ren ◽  
Gongbo Zhou ◽  
...  
Keyword(s):  
Fault Diagnosis ◽  
Correlation Coefficient ◽  
Feature Space ◽  
Support Vector ◽  
Vibration Signals ◽  
Bearing Fault ◽  
Bearing Fault Diagnosis ◽  
Acceleration Sensors ◽  
Reconstructed Signal ◽  
Original Feature

Acceleration sensors are frequently applied to collect vibration signals for bearing fault diagnosis. To fully use these vibration signals of multi-sensors, this paper proposes a new approach to fuse multi-sensor information for bearing fault diagnosis by using ensemble empirical mode decomposition (EEMD), correlation coefficient analysis, and support vector machine (SVM). First, EEMD is applied to decompose the vibration signal into a set of intrinsic mode functions (IMFs), and a correlation coefficient ratio factor (CCRF) is defined to select sensitive IMFs to reconstruct new vibration signals for further feature fusion analysis. Second, an original feature space is constructed from the reconstructed signal. Afterwards, weights are assigned by correlation coefficients among the vibration signals of the considered multi-sensors, and the so-called fused features are extracted by the obtained weights and original feature space. Finally, a trained SVM is employed as the classifier for bearing fault diagnosis. The diagnosis results of the original vibration signals, the first IMF, the proposed reconstruction signal, and the proposed method are 73.33%, 74.17%, 95.83% and 100%, respectively. Therefore, the experiments show that the proposed method has the highest diagnostic accuracy, and it can be regarded as a new way to improve diagnosis results for bearings.

Field-emitter cathode for acceleration sensors

1995 ◽  
Vol 5 (4) ◽  
pp. 282-288 ◽  
Author(s):  
A Hariz ◽  
H G Kim ◽  
M R Haskard ◽  
I J Chung
Keyword(s):  
Field Emitter ◽  
Acceleration Sensors

Investigations on the Receptors of the Vestibular Apparatus as Angular Acceleration Sensors

1968 ◽  
Vol 2 (4) ◽  
pp. 311-317
Author(s):  
V.M. Gusev ◽  
V.A. Kislyakov ◽  
M.M. Levashov ◽  
I.V. Orlov ◽  
R.I. Polonnikov
Keyword(s):  
Angular Acceleration ◽  
Vestibular Apparatus ◽  
Acceleration Sensors
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