scholarly journals A Novel Two-Axis Differential Resonant Accelerometer Based on Graphene with Transmission Beams

Sensors ◽  
2022 ◽  
Vol 22 (2) ◽  
pp. 641
Author(s):  
Yang Xiao ◽  
Feng Hu ◽  
Yuchen Zhang ◽  
Jiaxing Zheng ◽  
Shiqiao Qin

In this paper, a novel two-axis differential resonant accelerometer based on graphene with transmission beams is presented. This accelerometer can not only reduce the cross sensitivity, but also overcome the influence of gravity, realizing fast and accurate measurement of the direction and magnitude of acceleration on the horizontal plane. The simulation results show that the critical buckling acceleration is 460 g, the linear range is 0–89 g, while the differential sensitivity is 50,919 Hz/g, which is generally higher than that of the resonant accelerometer reported previously. Thus, the accelerometer belongs to the ultra-high sensitivity accelerometer. In addition, increasing the length and tension of graphene can obviously increase the critical linear acceleration and critical buckling acceleration with the decreasing sensitivity of the accelerometer. Additionally, the size change of the force transfer structure can significantly affect the detection performance. As the etching accuracy reaches the order of 100 nm, the critical buckling acceleration can reach up to 5 × 104 g, with a sensitivity of 250 Hz/g. To sum up, a feasible design of a biaxial graphene resonant accelerometer is proposed in this work, which provides a theoretical reference for the fabrication of a graphene accelerometer with high precision and stability.

2012 ◽  
Vol 479-481 ◽  
pp. 18-22
Author(s):  
Jing Li ◽  
Shang Chun Fan ◽  
Zhan She Guo

A resonant accelerometer was designed in order to overcome low output precision characteristics of the sensors which were tested with analog signals. This accelerator has the advantages of good repeatability, high resolution and excellent stability. Relationship between linear acceleration and resonant frequency of the sensing unit was deduced and the finite element method was used to simulate the correctness of the design. The theoretical and simulation results are 2984.47 and 2971.27 respectively without acceleration applied on this sensor. When 1g acceleration applied on this sensor, the theoretical and simulation results are 2970.18 and 2951.78 . The relative errors are 0.44% and 0.62% respectively. Finally, the fabricated sensor was tested, and the measured resonant frequency is 3022.55 with a relative error 1.26%, and we give out the possible reasons for this error. The results indicate that this design is feasible.


2011 ◽  
Vol 32 (5) ◽  
pp. 055007 ◽  
Author(s):  
Lichong Sun ◽  
Wenliang Ren ◽  
Na Yan ◽  
Hao Min

Sensors ◽  
2015 ◽  
Vol 15 (12) ◽  
pp. 30293-30310 ◽  
Author(s):  
Jing Zhang ◽  
Yan Su ◽  
Qin Shi ◽  
An-Ping Qiu

2017 ◽  
Vol 32 (3) ◽  
pp. 352-356 ◽  
Author(s):  
Jeong Goo Kim ◽  
Soyoung Shin ◽  
Joonhong Park

Background DNA mismatch repair deficiency is an important molecular mechanism of genetic instability in gastric cancer, and a high instability at microsatellites is associated with favorable prognosis. We compared mononucleotide and dinucleotide microsatellite instability (MSI) marker panels in 56 paired gastric tumor and normal samples. Methods The mononucleotide marker panel (mono panel) consisted of 8 markers: BAT25, BAT26, BAT40, BAT-RII, NR21, NR22, NR24 and NR27. The dinucleotide marker panel (di panel) contained D2S123, D5S346, D17S250, D17S261, D17S520, D18S34 and D18S58. The NCI panel was used as reference panel. Results Among 13 gastric tumors showing no hMLH1 or hMSH2 expression, 8 MSI-H (high) and 5 MSI-L (low) were identified. The analytical sensitivities of the NCI, mono and di panels to detect unstable MSI were 61.5% (8/13), 76.9% (10/13) and 84.6% (11/13), respectively. The size change of allele shift was statistically greater in the mono panel than in the di panel (p = 0.02 by Mann-Whitney U-test). The BAT40 (69.2%, 9/13) and D18S34 (76.9%, 10/13) markers showed high sensitivity for determination of MSI status. Conclusions To improve the detection rate of MSI in gastric cancer with loss of hMLH1 or hMSH2 expression, the kind of MSI marker may need to be considered more, instead of the repetitive type of marker. Thus, an MSI panel designed with a combination of both BAT40 and D18S34 is suggested for providing more accurate and sensitive MSI analysis in gastric cancer.


Author(s):  
R. W. Toogood

Abstract A number of programs have been developed for the automatic symbolic generation of efficient computer code for the dynamic analysis of serial rigid and flexible link manipulators. Code for both the inverse and the direct dynamics computations can be generated. The symbolic generators allow the robot base to be given an arbitrary linear acceleration anchor angular velocity and acceleration. The efficiency of the generated code is an important consideration for simulation studies and/or implementation in control systems. This paper briefly describes the symbolic generation and simplification techniques. The added computational load due to including the base motion is discussed. Some dynamics simulation results are presented for a 3R rigid link manipulator mounted on an oscillating base, which graphically illustrates the effect of the base movement on the dynamics.


Sensors ◽  
2018 ◽  
Vol 18 (10) ◽  
pp. 3258 ◽  
Author(s):  
Valery Gupalov ◽  
Alexander Kukaev ◽  
Sergey Shevchenko ◽  
Egor Shalymov ◽  
Vladimir Venediktov

The paper considers the construction of a piezoelectric accelerometer capable of measuring constant linear acceleration. A number of designs are proposed that make it possible to achieve high sensitivity with small dimensions and a wide frequency band (from 10−5 Hz). The finite element model of the proposed design was investigated, and its output characteristic and scale factor (36 mV/g) were obtained.


2020 ◽  
Author(s):  
Randall Parrish ◽  
Robert Haley

Abstract Background: Of the hypothesized causes of Gulf War Illness (GWI), a chronic multi-symptom illness afflicting approximately 25 percent of >700,000 military personnel deployed to the 1991 Gulf War, depleted uranium (DU) and exposure to nerve agents have stimulated the most intense international concern. Past depleted uranium research on Gulf War veterans has measured urinary uranium concentration [U] and uranium isotopic ratios with low precision mass spectrometry primarily in GW veterans with retained shrapnel but has not used high precision mass spectrometry to test for an association of GWI with inhaled DU and we set out to test this potential association. Methods: We applied a standard biokinetic model to predict the urinary total [U] and uranium isotopic ratios in urine 18 years after inhalation exposure. We applied high sensitivity mass spectrometry methods capable of detecting the predicted levels in 154 individuals of a population-representative sample of U.S. veterans in whom Gulf War illness had been determined by standard case definitions and DU inhalation exposures obtained by medical history. Results: Methods used in past studies are capable of detecting only the high urinary uranium excretion levels from retained DU shrapnel but not lower levels predicted from DU inhalation. Using high precision mass spectrometry, we found no difference in the 238U/235U ratio in veterans meeting the standard case definitions of GWI versus control veterans, and no differences by levels of DU inhalation exposure. Our bivariate analysis of 236U/238U by 235U/238U showed only the signature of natural dietary uranium, excluding DU inhalation exposures above 0.4 mg, far below the disease-causing threshold. Conclusion: The findings by high precision mass spectrometry support the conclusion that even the highest levels of DU inhalation played no role in the development of Gulf War illness. Other factors including exposure to aerosolized organophosphate compounds (pesticides and sarin nerve agent) remain as the most likely cause(s) of GWI.


2011 ◽  
Vol 230-232 ◽  
pp. 1379-1383
Author(s):  
Peng Yao ◽  
Gai Rong Chen ◽  
Shao Hong Xu

According to pseudo-periodicity and ergodicity of chaotic systems, we put forward a fast algorithm to determine delay time in phase state reconstruction. The traditional method to calculate mutual information is time-consuming and complicated to realize, which greatly restricts its application. In our algorithm we gradually reduce the feasible computing interval and adjust the calculating step until satisfactory result is gotten. This method overcomes the tedious calculation of mutual information and meanwhile guarantees high precision. Finally the simulation results of Rössler and Lorenz systems verify the feasibility of our algorithm.


Sign in / Sign up

Export Citation Format

Share Document