Measurement of Laser Ablation Micro Impulse Using the Torsion Pendulum Interferometry

2011 ◽  
Vol 301-303 ◽  
pp. 1078-1082
Author(s):  
Ji Fei Ye ◽  
Guang Yu Wang ◽  
Dian Kai Wang
Keyword(s):  
Laser Ablation ◽  
Measurement Technique ◽  
Laser Plasma ◽  
Measurement Method ◽  
Torsion Pendulum ◽  
Differential Interferometry ◽  
Plasma Thruster ◽  
Important Measurement

A method is described for measuring the micro impulse induced by the laser ablation. This method is based upon the torsion pendulum interferometry technique. The method measures the micro impulse through the detection of the swinging angle of torsion pendulum. The swinging angle is obtained by the laser differential interferometry. For the 10-4~10-7 magnitude micro-impulse, It could be the important measurement method in the research of micro laser plasma thruster (mLPT). The results of some preliminary experiments are presented with detailed reference to experiment methodology and accuracy. The measurement technique is well suited to cases seeking the measurement of mN×s magnitude micro-impulse.

scholarly journals A Repeatable and Reproducible Digital Method to Quantify the Cement Excess and Enamel Loss after Debonding Lingual Multibracket Appliance Therapy

2021 ◽  
Vol 11 (3) ◽  
pp. 1295
Author(s):  
Alba Belanche Monterde ◽  
Alberto Albaladejo Martínez ◽  
Alfonso Alvarado Lorenzo ◽  
Adrián Curto ◽  
Jorge Alonso Pérez-Barquero ◽  
...  
Keyword(s):  
Measurement Technique ◽  
Measurement Method ◽  
Dental Arch ◽  
Micro Computed Tomography ◽  
Morphometric Measurement ◽  
Before And After ◽  
Repeatability And Reproducibility ◽  
Lingual Brackets ◽  
Multibracket Appliance ◽  
Area And Volume

The aim of the present study is to present a repeatable, reproductible, and accurate morphometric measurement method for measuring and quantifying the area and volume of cement that remains after fixed lingual multibracket appliance debonding, enamel loss after fixed lingual multibracket appliance debonding, and the volume of cement used to adhere fixed lingual multibracket appliances. Ten conventional lingual brackets were cemented in 10 extracted teeth embedded into an epoxy resin model simulating a dental arch. This model was scanned before and after bonding the lingual brackets, after debonding, and after polishing the surfaces. We also performed a Micro-Computed Tomography scan of the lingual brackets used. Afterward, the standard tessellation language (STL) digital file was aligned, each tooth was segmented individually, and the file was re-aligned using engineer morphometry software. Inter-operator and intra-operator comparative analyses were performed using the ANOVA test, and the repeatability and reproducibility of the morphometric measurement technique were analyzed using Gage R&R statistical analysis. Repeatability showed 0.07% and 0.16% variability associated with the area and volume measures, respectively, while reproducibility showed 0.00% variability associated with the area and volume measures, respectively. In conclusion, the morphometric measurement technique is a repeatable, reproductible, and accurate morphometric measurement method for quantifying the area and volume of cement that remains after fixed lingual multibracket appliance debonding, enamel loss after fixed lingual multibracket appliance debonding, and the volume of cement used to adhere fixed lingual multibracket appliances.

scholarly journals Reliability Evaluation of the Joint Observation of Cloud Top Height by FY-4A and HIMAWARI-8

2021 ◽  
Vol 13 (19) ◽  
pp. 3851
Author(s):  
Qinghui Li ◽  
Xuejin Sun ◽  
Xiaolei Wang
Keyword(s):  
Measurement Method ◽  
Satellite Observation ◽  
Geostationary Satellite ◽  
Cloud Type ◽  
Surface Type ◽  
Geostationary Satellites ◽  
Good Consistency ◽  
Passive Sensors ◽  
Cloud Optical Thickness ◽  
Important Measurement

It is well known that the measurement of cloud top height (CTH) is important, and a geostationary satellite is an important measurement method. However, it is difficult for a single geostationary satellite to observe the global CTH, so joint observation by multiple satellites is imperative. We used both active and passive sensors to evaluate the reliability of joint observation of geostationary satellites, which includes consistency and accuracy. We analyzed the error of CTH of FY-4A and HIMAWARI-8 and the consistency between the two satellites and conducted research on the problem of missing measurement (Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) has CTH data, but FY-4A/HIMAWARI-8 does not) of the two satellites. The results show that FY-4A and HIMAWARI-8 have good consistency and can be jointly observed, but the measurement of CTH of FY-4A and HIMAWARI-8 has large errors, and the error of FY-4A is greater than that of HIMAWIRI-8. The error of CTH is affected by the CTH, cloud optical thickness (COT) and cloud type, and the consistency between the two satellites is mainly affected by the cloud type. FY-4A and HIMAWARI-8 have the problem of missing measurement. The missing rate of HIMAWARI-8 is greater than that of FY-4A, and the missing rate is not affected by the CTH, COT and surface type. Therefore, although FY-4A and HIMAWARI-8 have good consistency, the error of CTH and the problem of missing measurement still limit the reliability of their joint observation.

scholarly journals Modification of Hot-Wire Anemometers Frequency Bandwidth Measurement Method

Sensors ◽  
2020 ◽  
Vol 20 (6) ◽  
pp. 1595
Author(s):  
Paweł Ligęza
Keyword(s):  
Measurement Technique ◽  
Measurement Method ◽  
Sine Wave ◽  
Frequency Bandwidth ◽  
Hot Wire ◽  
Electrical Test ◽  
Modified Method ◽  
Key Issues ◽  
Wire System

In measurements of fast-changing flows, one of the key issues is knowledge of the anemometer frequency bandwidth. In such measurements, the measurement technique often used is hot-wire anemometry. The determination and optimization of the measurement bandwidth of the hot-wire system is very important for the quality of the measurements carried out. One of the methods used is square-wave or sine-wave electrical testing. The article proposes modification of this method, which involves applying an electrical test signal wirelessly directly to the sensor, using transformer inductive coupling. This modification may in some cases be beneficial and find application in selected metrological problems. The article describes the modified method and its example application.

Effects of Confined Laser Ablation on Laser Plasma Propulsion

2005 ◽  
Vol 22 (7) ◽  
pp. 1725-1728 ◽  
Author(s):  
Zheng Zhi-Yuan ◽  
Zhang Jie ◽  
Lu Xin ◽  
Hao Zuo-Qiang ◽  
Xu Miao-Hua ◽  
...  
Keyword(s):  
Laser Ablation ◽  
Laser Plasma ◽  
Plasma Propulsion

Correlation of Raman Spectra and Bonding in DLC Films Deposited by Laser Ablation and Laser-Plasma Ablation Techniques

1991 ◽  
Vol 250 ◽  
Author(s):  
A. Rengan ◽  
J. Narayan ◽  
J. L. Park
Keyword(s):  
Laser Ablation ◽  
Laser Plasma ◽  
Deposition Temperature ◽  
Plasma Deposition ◽  
Raman Shift ◽  
Plasma Ablation ◽  
Valence Electrons ◽  
Diamondlike Carbon ◽  
Plasma Deposited Films ◽  
Deposited Films

AbstractWe have deposited diamondlike carbon (DLC) films on a variety of substrates from 250° C and higher. The effects of deposition temperature on the properties of DLC films deposited by a conventional laser ablation technique are compared with that of a unique laser-plasma deposition scheme. The calculated values of neff, the effective number of valence electrons, suggest that, with the increase in the deposition temperature, the diamondlike component (sp3 bonds) remains invariant for the laser deposited samples, and increases for the laser-plasma deposited films. Raman measurements show that the Raman allowed ‘G’ band upshifts to ˜1600 cm−1 for both deposition schemes. However, the disorder induced 'D' band remains invariant at ˜1370 cm−2 for the laser ablated samples, and downshifts to ˜1350 cm−1 for the laser-plasma deposited samples. These results suggest a correlation between the diamondlike content (sp3 bonds) and the Raman shift of the ‘D’ band.

scholarly journals The LMS-GT instrument – a new perspective for quantification with the LIMS-TOF measurement technique

2019 ◽  
Vol 34 (10) ◽  
pp. 2061-2073 ◽  
Author(s):  
Reto Wiesendanger ◽  
Valentine Grimaudo ◽  
Marek Tulej ◽  
Andreas Riedo ◽  
Rustam Lukmanov ◽  
...  
Keyword(s):  
Laser Ablation ◽  
Mass Spectrometer ◽  
Measurement Technique ◽  
High Performance ◽  
Mass Resolution ◽  
Solid Sample ◽  
Sample Analysis ◽  
New Perspective ◽  
Solid Sample Analysis

A new high-performance laser ablation and ionisation (LIMS) mass spectrometer for solid sample analysis with micrometer spatial- and up to 10 000 mass resolution is presented.

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