Two-wavelength sinusoidal phase-modulating interferometer for nanometer accuracy measurement

2012 ◽  
Vol 10 (7) ◽  
pp. 071202-71205
Author(s):  
Bofan Wang Bofan Wang ◽  
Zhongliang Li Zhongliang Li ◽  
Xiangzhao Wang Xiangzhao Wang
Keyword(s):  
Accuracy Measurement ◽  
Sinusoidal Phase Modulating

Evidence-based diagnostic accuracy measurement in urine cytology using likelihood ratios

2020 ◽  
Author(s):  
Nickolas Myles ◽  
Manon Auger ◽  
Yonca Kanber ◽  
Derin Caglar ◽  
Wassim Kassouf ◽  
...  
Keyword(s):  
Diagnostic Accuracy ◽  
Urine Cytology ◽  
Evidence Based ◽  
Likelihood Ratios ◽  
Accuracy Measurement

A normal section plane method for profile error analysis of five-axis machine tools based on the ideal tool flank milling surface

2021 ◽  
pp. 095440622110426
Author(s):  
Liping Wang ◽  
Meng Fu ◽  
Liwen Guan ◽  
Yanyu Chen
Keyword(s):  
Contact Point ◽  
Flank Milling ◽  
Section Plane ◽  
Profile Error ◽  
Plane Method ◽  
Normal Section ◽  
Accuracy Measurement ◽  
Machine Tool Accuracy ◽  
Milled Surface ◽  
The Impact

The existing studies on profile error analysis and machining accuracy measurement do not consider the impact of the theoretical errors on the machine tool accuracy measurement. Therefore, this study proposes an estimation method of the surface profile error based on the normal section plane, using the theoretical flank milled surface for comparison. This effectively improves the accuracy of profile error estimation. The theoretical flank milled surface is the surface machined by flank milling under ideal conditions. Hence, compared to the traditional analysis method based on the designed three-dimensional model of S-shaped test pieces, the calculated profile error of this method does not include theoretical errors, thereby eliminating the impact of theoretical errors on machine tool accuracy measurement and evaluation. First, an improved method for continuous parameterized dual spline interpolation was proposed. It simplifies the solution of the singular problem of the coefficient matrix of the spline basis function and obtains a continuous ideal machining tool axis trajectory surface with complete geometric characteristics. Next, a method for constructing the theoretical flank milled surface machined with a cylindrical milling tool using equidistant mapping characteristics was proposed; then, the differential transformation relationship at the cutting contact point of the curved surface under the influence of tool path errors was established. Furthermore, the normal section plane method based on the differentiation of the cutting contact point was proposed. The problem of solving the distance from a point to a surface is converted to the problem of solving the distance from a point to a curve in the normal section plane. This improves the accuracy of profile error estimation. The effectiveness of the method was verified by comparing the analysis results of the profile errors of a typical cylindrical surface with the point to surface and the point to curve methods.

High accuracy measurement of the ground-state hyperfine splitting in a 113Cd+ microwave clock: erratum

2021 ◽  
Vol 46 (20) ◽  
pp. 5207
Author(s):  
K. Miao ◽  
J. W. Zhang ◽  
X. L. Sun ◽  
S. G. Wang ◽  
A. M. Zhang ◽  
...  
Keyword(s):  
Ground State ◽  
Hyperfine Splitting ◽  
High Accuracy ◽  
Accuracy Measurement ◽  
High Accuracy Measurement

Kajian Akurasi Pengukuran dan Pemetaan Bidang Tanah Produk Kantor Jasa Surveyor Berlisensi (Studi di Kantor Pertanahan Kabupaten Kediri dan Tulungagung)

Tunas Agraria ◽  
2020 ◽  
Vol 3 (2) ◽  
pp. 140-156
Author(s):  
Evan Sulton Yulianto ◽  
Abdul Haris Farid
Keyword(s):  
Quantitative Approach ◽  
Accuracy Measurement ◽  
Physical Data ◽  
Descriptive Method

Abstract: The collection of physical data is regulated in JUKNIS PMNA/KBPN Number 3 of 1997. In the technical guidelines, determinate where the results of measuring and mapping land parcels have to accordance with determined tolerances, namely tolerance of distance, area, form and registration map. But in reality, the results of the measurement and mapping of land parcels by KJSKB still do not fulfill the tolerance requirements. This study aims to determine the level of accuracy of the results of measurements and mapping of land parcels conducted by KJSKB. This study uses a descriptive method with a quantitative approach. The comparison of distances in Butuh Village were 42 distances (36.52%) suitable and 73 distances (63.48%) did not, in Jeli Village, there were 74 distances (55.64%) suitable and 59 distances (44.36%) did not. The results of the comparison of area in Butuh Village are 23 land parcels (76.67%) suitable and 7 land parcels (23.33%) did not, in Jeli Village as many as 20 land parcels (66.67%) suitable and 10 land parcels (33.33%) did not. In addition to the form variables and registration maps, some land parcels do not match between the Measuring Image and the field conditions.Keywords: accuracy, measurement, mapping, KJSKB. Intisari: Pelaksanaan pengumpulan data fisik diatur dalam JUKNIS PMNA/KBPN Nomor 3 tahun 1997. Di dalam Juknis tersebut, terdapat ketentuan dimana hasil pengukuran dan pemetaan bidang tanah harus sesuai dengan toleransi yang telah ditetapkan yaitu toleransi jarak, luas, bentuk, dan peta pendaftaran. Namun kenyataannya, hasil pengukuran dan pemetaan bidang tanah oleh KJSKB masih belum memenuhi syarat toleransi. Penelitian ini bertujuan untuk mengetahui tingkat akurasi hasil pengukuran dan pemetaan bidang-bidang tanah yang dilakukan oleh KJSKB. Penelitian ini menggunakan metode deskriptif dengan pendekatan kuantitatif. Hasil perbandingan jarak di Desa Butuh sebanyak 42 jarak (36.52%) Sesuai dan 73 jarak (63.48%) Tidak Sesuai, di Desa Jeli sebanyak 74 jarak (55.64%) Sesuai dan 59 jarak (44.36%) Tidak Sesuai. Hasil perbandingan luas di Desa Butuh sebanyak 23 bidang tanah (76.67%) Sesuai dan 7 bidang tanah (23.33%) Tidak Sesuai, di Desa Jeli sebanyak 20 bidang tanah (66.67%) Sesuai dan 10 bidang tanah (33.33%) Tidak Sesuai. Selain itu pada variabel bentuk dan peta pendaftaran, beberapa bidang tanah tidak sesuai antara Gambar Ukur dan keadaan lapangan.Kata Kunci: akurasi, pengukuran, pemetaan, KJSKB. 

scholarly journals Network method for deformation analysis of three-dimensional point cloud with terrestrial laser scanning sensor

2018 ◽  
Vol 14 (11) ◽  
pp. 155014771881413 ◽  
Author(s):  
Xiangyang Xu ◽  
Hao Yang
Keyword(s):  
Point Cloud ◽  
Laser Scanning ◽  
Three Dimensional ◽  
Terrestrial Laser Scanning ◽  
Deformation Analysis ◽  
Transverse Displacement ◽  
Displacement Analysis ◽  
Accuracy Measurement ◽  
Network Method ◽  
Displacement Information

The complexity of structural materials is increasing the importance of the technology for high accuracy measurement. How to obtain the displacement information of structural feature points accurately and efficiently is the key issue of deformation analysis. In this article, displacement analysis of a composite arched structure is investigated based on the terrestrial laser scanning technique. A new method based on the measured point cloud is proposed to analyze the displacement of surficial points, resulting in not only the displacement size but also the displacement direction. The innovation lies in extracting the displacement information with a network and remapped point cloud, which is called the network method. The displacement map obtained demonstrates that the transverse displacement in the experiment plays an important role in the safety of the structure, which could not be observed and obtained by the surface approximation method. Therefore, the panorama- and pointwise displacement analysis technologies contribute to ensure the safety of increasingly complex constructions.

Rotating Accuracy Measurement System of Spindle Based on Three Point Method

2013 ◽  
Vol 333-335 ◽  
pp. 167-171
Author(s):  
Peng Qing Wang ◽  
Hong Jun Wang ◽  
He Peng Gao
Keyword(s):  
Personal Computer ◽  
Rotating Machinery ◽  
Point Method ◽  
Measuring System ◽  
Harmonic Suppression ◽  
Construction Site ◽  
Software Module ◽  
Accuracy Measurement ◽  
Sensor Arrangement ◽  
On Line

In order to measure the rotating machinery fault quickly and conveniently at a construction site, a new measuring system of rotating accuracy of spindle was developed according to three point method. With summarizing the principle of error separation technique based on three point method, the function, hardware construction and software module of this module were introduced. The problem of harmonic suppression is relieved by changing the sensor arrangement. The measuring system mainly consists of three eddy current sensors ,a acquisition card and a personal computer. After a few parameters were inputted, the rotation accuracy of calculation and display could be carried out automatically on line at a construction site.

scholarly journals Development of a Novel Double-Ring Deployable Mesh Antenna

2012 ◽  
Vol 2012 ◽  
pp. 1-10 ◽  
Author(s):  
Yan Xu ◽  
Fuling Guan ◽  
Xian Xu ◽  
Hongjian Wang ◽  
Yao Zheng
Keyword(s):  
Low Frequency ◽  
Design Concept ◽  
Design Parameters ◽  
Accuracy Measurement ◽  
Double Ring ◽  
Reflective Surface ◽  
Final Design ◽  
Geometric Relationship ◽  
Relationship Of ◽  
Adjustment Test

This paper addresses a type of deployable mesh antenna consisting of the double-ring deployable truss edge frame and the cable net reflector. The structural design concept of the deployable antennas is presented. The deployable truss is designed and the geometric relationship of each strut length is formulated. Two types of radial truss elements are described and compared. The joint pattern and the active cables of the final design concept are determined. The pattern of the cable net is the three-orientation grid. Two connection schemes between the reflector and the deployable edge frame are investigated. The design parameters and the shape adjustment mechanism of this cable net are determined. The measurement test technologies of the antennas on the ground including test facilities, deployment test, and measurement and adjustment test are proposed. The antenna patterns are analyzed based on the real surfaces of the reflector obtained by the reflective surface accuracy measurement. The tests and analytic results indicated that the accuracy of the reflective surface is high and is suitable for low-frequency communication.

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