scholarly journals Simple method to determine linearity deviations of topography measuring instruments with a large range axial scanning system

2020 ◽  
Vol 64 ◽  
pp. 243-248 ◽  
Author(s):  
Wilfried Bauer ◽  
Dorothee Hüser ◽  
David Gerbert
Keyword(s):  
Large Range ◽  
Measuring Instruments ◽  
Scanning System ◽  
Simple Method ◽  
Axial Scanning

scholarly journals Simple Method to Determine Linearity Deviations of Topography Measuring Instruments with a Large Range Axial Scanning System

2020 ◽  
Author(s):  
Dorothee Hueser
Keyword(s):  
Amplification Factor ◽  
Control Process ◽  
Measuring Instruments ◽  
Scanning System ◽  
Dimensional Metrology ◽  
Simple Method ◽  
System P ◽  
Material Measure ◽  
Axial Scanning

The use of areal characterization of surface texture with high accuracy in aquality control process requires reliability. Therefore, regular inspection of themeasurement systems is needed. Important metrological features of a measure-ment system in dimensional metrology are the amplification factor and linearity.This paper presents a simple method for characterizing the axial scanningsystem of areal topography measuring instruments with little expense and effort,well suited for industrial routine calibration in the field. The method is based onemploying a single material measure with a range of step heights. It is shownthat the amplification factor and linearity deviations can be determined andadjusted for large axial measurement ranges.

scholarly journals IMAGING OF CORROSION PITS ON METALLIC PIPES USING A LASER SCANNER

2011 ◽  
Author(s):  
Homayoun Najjaran
Keyword(s):  
Laser Scanning ◽  
Laser Scanner ◽  
Scanning Speed ◽  
Displacement Sensor ◽  
Statistical Characteristics ◽  
Measuring Instruments ◽  
Scanning System ◽  
Laser Measurements ◽  
Corrosion Pits ◽  
Pit Depth

This paper describes the hardware and software of a laser scanning system that is used to produce 3D images of external surfaces of pipes. The images are produced in the form of 3D raster images with a resolution of up to 0.1×0.1 mm and an accuracy of 3-10 microns, depending on the desired scanning speed, to portray the corrosion pits on the pipes. The main application of the scanner is to establish patterns for calibrating nondestructive testing techniques (e.g., Remote Field Eddy Current (RFEC) and ultrasound testing that are commonly used to measure the remaining wall thickness of ductile and cast iron pipes), and also identifying the statistical characteristics of the measuring instruments utilized in those methods. The images may also be useful to scrutinize corrosion and failure mechanisms, especially when estimates of average or maximum pit depth are insufficient. The scanning system consists of a 2-DOF robot that can move a laser displacement sensor along a pipe and an instrumented rig that rotates the pipe about its axis. Rotating the pipe and moving the rangefinder along the pipe’s axis, the scanning system acquires laser measurements into a host computer to produce the image. The paper also presents the images and statistical analysis of corrosion pits of pipe samples exhumed and sandblasted for scanning.

Fast axial scanning system based on digital micromirror device

2017 ◽  
Vol 38 (1) ◽  
pp. 527-531
Author(s):  
Zhan Weina ◽  
Lu Jingqi ◽  
Liu Yangzan ◽  
Jia Xinting ◽  
Tao Jun
Keyword(s):  
Scanning System ◽  
Digital Micromirror Device ◽  
Axial Scanning

scholarly journals A new simple method for determining the sound absorption coefficient

2018 ◽  
Vol 211 ◽  
pp. 04003
Author(s):  
Merab Chelidze
Keyword(s):  
Absorption Coefficient ◽  
Sound Absorption ◽  
Sound Propagation ◽  
Sound Absorption Coefficient ◽  
Measuring Instruments ◽  
Sound Waves ◽  
Simple Method ◽  
Impedance Tube ◽  
Wide Range ◽  
Low Sensitivity

Taking into account the influence of the length and diameter of the impedance tube on the process of decay of sound waves, a new study of sound propagation in an impedance tube is presented, on the basis of which it is easier to determine the sound absorption coefficient. The new simple method of determining the absorption coefficient, based on the decay of reverberating waves, is fairly stable and demonstrates a low sensitivity for all errors made in the measurement. The presented method makes it possible to measure the sound absorption coefficient without laboratories and precision measuring instruments in a wide range at the level of separate consumers.

scholarly journals Determination of Vitamin B12 in Food Products by Liquid Chromatography/UV Detection with Immunoaffinity Extraction: Single-Laboratory Validation

2008 ◽  
Vol 91 (4) ◽  
pp. 786-793 ◽  
Author(s):  
Esther Campos-Gimnez ◽  
Patric Fontannaz ◽  
Marie-Jose Trisconi ◽  
Tamara Kilinc ◽  
Catherine Gimenez ◽  
...  
Keyword(s):  
Liquid Chromatography ◽  
Standard Deviation ◽  
Vitamin B12 ◽  
Large Range ◽  
Uv Detection ◽  
Average Standard Deviation ◽  
Simple Method ◽  
Relative Standard ◽  
Single Laboratory

Abstract A fast and simple method to determine vitamin B12 in foods is presented. The method allows, in addition to the determination of added cyanocobalamin, the determination of natural vitamin B12 forms, making it also applicable to nonfortified products, especially those that are milk-based. Vitamin B12 is extracted in sodium acetate buffer in the presence of sodium cyanide (100C, 30 min). After purification and concentration with an immunoaffinity column, vitamin B12 is determined by liquid chromatography with UV detection (361 nm). The method has been validated in analyses of a large range of products: milk- and soy-based infant formulas, cereals, cocoa beverages, health care products, and polyvitamin premixes. The method showed appropriate performance characteristics: linear response over a large range of concentrations, recovery rates of 100.8 7.5 (average standard deviation), relative standard deviation of repeatability, RSDr, of 2.1, and intermediate reproducibility, RSDiR, of 4.3. Limits of detection and quantitation were 0.10 and 0.30 g/100 g, respectively, and correlation with the reference microbiological assay was good (R2= 0.9442). The proposed method is suitable for the routine determination of vitamin B12 in fortified foods, as well as in nonfortified dairy products. It can be used as a faster, more selective, and more precise alternative to the classical microbiological determination.

Concept of a new PZT

1978 ◽  
Vol 48 ◽  
pp. 271-278
Author(s):  
Chr. Kühne
Keyword(s):  
Mirror System ◽  
Measuring Instruments

The PZT according to MARKOWITZ, undoubtedly one of the most accurate measuring instruments, has become an integral part of astronomy in the last years. Yet there are two reasons why I still tried to improve the MARKOWITZ basic idea.For the MARKOWITZ process the use of a lens objective is imperative. Because of the diameter limitations of the lens objectives the magnitude is reduced. Although a 65 cm PZT has been put into operation in Washington recently, the thermal difficulties encountered made it necessary to control the temperature actively. In addition, the 65 cm diameter of a lens equipped with 4 elements can be considered as the very limit, but not for a mirror system.In addition there are still more disadvantages using lens objectives. The useable field is restricted by astigmatism, reducing the range of declination. The transmission, especially in the blue wavelengths, decreases very rapidly with the thickness of lenses. For large multilens objectives the transmission is less than for a mirror system.

A simple way for producing holographic filters suitable for image improvement

1978 ◽  
Vol 36 (1) ◽  
pp. 226-227
Author(s):  
K.-H. Herrmann ◽  
E. Reuber ◽  
P. Schiske
Keyword(s):  
Transfer Functions ◽  
Diffraction Order ◽  
Lateral Position ◽  
Simple Method ◽  
Spatial Frequencies ◽  
Resolution Electron ◽  
Wiener Filters ◽  
Image Improvement ◽  
Optical Reconstruction ◽  
Set Up

Aposteriori deblurring of high resolution electron micrographs of weak phase objects can be performed by holographic filters [1,2] which are arranged in the Fourier domain of a light-optical reconstruction set-up. According to the diffraction efficiency and the lateral position of the grating structure, the filters permit adjustment of the amplitudes and phases of the spatial frequencies in the image which is obtained in the first diffraction order.In the case of bright field imaging with axial illumination, the Contrast Transfer Functions (CTF) are oscillating, but real. For different imageforming conditions and several signal-to-noise ratios an extensive set of Wiener-filters should be available. A simple method of producing such filters by only photographic and mechanical means will be described here.A transparent master grating with 6.25 lines/mm and 160 mm diameter was produced by a high precision computer plotter. It is photographed through a rotating mask, plotted by a standard plotter.

Rotary Beveling for In Situ Thin-Section Microscopy of Cell Cultures

1981 ◽  
Vol 39 ◽  
pp. 550-551
Author(s):  
Dean A. Handley ◽  
Jack T. Alexander ◽  
Shu Chien
Keyword(s):  
Cell Growth ◽  
Cell Cultures ◽  
Molecular Interactions ◽  
Convenient Method ◽  
Petri Dish ◽  
Simple Method ◽  
Thin Section Microscopy ◽  
Thin Sectioning ◽  
Organic Fluids

In situ preparation of cell cultures for ultrastructural investigations is a convenient method by which fixation, dehydration and embedment are carried out in the culture petri dish. The in situ method offers the advantage of preserving the native orientation of cell-cell interactions, junctional regions and overlapping configurations. In order to section after embedment, the petri dish is usually separated from the polymerized resin by either differential cryo-contraction or solvation in organic fluids. The remaining resin block must be re-embedded before sectioning. Although removal of the petri dish may not disrupt the native cellular geometry, it does sacrifice what is now recognized as an important characteristic of cell growth: cell-substratum molecular interactions. To preserve the topographic cell-substratum relationship, we developed a simple method of tapered rotary beveling to reduce the petri dish thickness to a dimension suitable for direct thin sectioning.

Small Computer System for Micrograph Analysis

1981 ◽  
Vol 39 ◽  
pp. 270-271
Author(s):  
J. F. Hainfeld ◽  
J. S. Wall
Keyword(s):  
Large Range ◽  
Small Computer ◽  
Black And White ◽  
Contour Maps ◽  
Points Of Interest ◽  
Computer Aided Analysis ◽  
Specialized Hardware ◽  
Additional Memory ◽  
Selection Of ◽  
Publication Quality

Cost reduction and availability of specialized hardware for image processing have made it reasonable to purchase a stand-alone interactive work station for computer aided analysis of micrographs. Some features of such a system are: 1) Ease of selection of points of interest on the micrograph. A cursor can be quickly positioned and coordinates entered with a switch. 2) The image can be nondestructively zoomed to a higher magnification for closer examination and roaming (panning) can be done around the picture. 3) Contrast and brightness of the picture can be varied over a very large range by changing the display look-up tables. 4) Marking items of interest can be done by drawing circles, vectors or alphanumerics on an additional memory plane so that the picture data remains intact. 5) Color pictures can easily be produced. Since the human eye can detect many more colors than gray levels, often a color encoded micrograph reveals many features not readily apparent with a black and white display. Colors can be used to construct contour maps of objects of interest. 6) Publication quality prints can easily be produced by taking pictures with a standard camera of the T.V. monitor screen.

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