Image Analysis—Turning Images Into Data

1998 ◽  
Vol 4 (S2) ◽  
pp. 58-59
Author(s):  
J. J. Friel ◽  
E. B. Prestridge
Keyword(s):  
Particle Size ◽  
Image Analysis ◽  
Volume Fraction ◽  
Automatic Image Analysis ◽  
Point Counting ◽  
Linear Measurements ◽  
Feature Descriptors ◽  
Digital Resolution ◽  
Contrast Mechanism ◽  
Manual Methods

Image analysis is the process of quantifying some aspect of an image—its particle size distribution, for example. Manual methods were in use long before computers made image analysis much faster and more reproducible. Linear measurements of diameter, point counting to measure volume fraction, and intercept counting to determine grain size have been used for over 100 years. Automatic image analysis (AIA), however, can make more measurements, and even calculate derived measurements, such as aspect ratio or circularity. AIA of a specimen or micrograph, of course, is only as good as the contrast mechanism used, so the imaging signal must be chosen carefully to reveal to the computer what is to be measured. Obtaining sufficient contrast is often the limiting task.Once an imaging signal is chosen and the digital resolution set, the computer can analyze the image. The feature descriptors can be generic:

Image Analysis of Faecal Material Grazed Upon by Three Species Of Copepods: Evidence For Coprorhexy, Coprophagy and Coprochaly

1991 ◽  
Vol 71 (2) ◽  
pp. 465-480 ◽  
Author(s):  
Thomas T. Noji ◽  
Kenneth W. Estep ◽  
Ferren Macintyre ◽  
Fredrika Norrbin
Keyword(s):  
Particle Size ◽  
Image Analysis ◽  
Organic Matter ◽  
Size Spectrum ◽  
Automatic Image Analysis ◽  
Faecal Material ◽  
The Third ◽  
Acartia Clausi ◽  
Sinking Velocities ◽  
Residency Time

Experiments involving three species of copepods(Acartia clausi Giesbrecht 1889, Pseudocalanus elongatus Boeck 1872 and Calanusfinmarchicus Gunnerus 1765) incubated with freshly produced copepod faecal material were conducted and analyzed using automatic image analysis. For two species (A. clausi and C. finmarchicus) the bulk of faecal material was not ingested but was fragmented. This process, coprorhexy, was accompanied by a shift toward smaller particles in the particle size-spectrum. Increases in total volume of the faecal particles after incubation with these copepods led us to propose a process which we refer to as 'coprochaly', derived from the Greek xot/Vaoio,(a loosening, as of bandages). Coprochaly was promoted by manipulation of the faecal material by the copepods. For the third species (P.elongatus) coprorhexy and coprochaly were coupled with coprophagy (ingestion of faecal material). Calculations indicated that the combined effect of coprorhexy and coprochaly reduced sinking velocities of the faecal particles by up to 50%. These processes increase pelagic residency time of particles, increase substrate area for aerobic microbes and presumably enhance remineralization of particulate organic matter.

A New System For Optomanual Semiautomatic Quantitative Image Analysis

1977 ◽  
Vol 35 ◽  
pp. 210-211
Author(s):  
H.P. Rohr
Keyword(s):  
Image Analysis ◽  
Volume Density ◽  
List Type ◽  
Distribution Analysis ◽  
Type Number ◽  
Point Counting ◽  
Human Eye ◽  
Quantitative Image ◽  
Point Density ◽  
Electronic Counting

Today, in image analysis the broadest possible rationalization and economization have become desirable. Basically, there are two approaches for image analysis: The image analysis through the so-called scanning methods which are usually performed without the human eye and the systems of optical semiautomatic analysis completely relying on the human eye.The new MOP AM 01 opto-manual system (fig.) represents one of the very promising approaches in this field. The instrument consists of an electronic counting and storing unit, which incorporates a microprocessor and a keyboard for choice of measuring parameters, well designed for easy use.Using the MOP AM 01 there are three possibilities of image analysis:the manual point counting,the opto-manual point counting andthe measurement of absolute areas and/or length (size distribution analysis included).To determine a point density for the calculation of the corresponding volume density the intercepts lying within the structure are scanned with the light pen.

Limitations of a 3-D Image Analysis-Based Particle Size Measuring System for Wood Particle Dimension Measurement

2018 ◽  
Vol 50 (3) ◽  
pp. 358-362
Author(s):  
Jan T Benthien ◽  
Jan Ludtke ◽  
Rainer Friehmelt ◽  
Michael Schafer
Keyword(s):  
Particle Size ◽  
Image Analysis ◽  
Wood Particle ◽  
Measuring System ◽  
Dimension Measurement ◽  
Particle Dimension

scholarly journals Jet Impingement Heat Transfer of Confined Single and Double Jets with Non-Newtonian Power Law Nanofluid under the Inclined Magnetic Field Effects for a Partly Curved Heated Wall

2021 ◽  
Vol 13 (9) ◽  
pp. 5086
Author(s):  
Fatih Selimefendigil ◽  
Hakan F. Oztop ◽  
Ali J. Chamkha
Keyword(s):  
Magnetic Field ◽  
Heat Transfer ◽  
Particle Size ◽  
Aspect Ratio ◽  
Power Law ◽  
Volume Fraction ◽  
Inclined Magnetic Field ◽  
Magnetic Field Effects ◽  
Power Law Nanofluid ◽  
Power Law Index

Single and double impinging jets heat transfer of non-Newtonian power law nanofluid on a partly curved surface under the inclined magnetic field effects is analyzed with finite element method. The numerical work is performed for various values of Reynolds number (Re, between 100 and 300), Hartmann number (Ha, between 0 and 10), magnetic field inclination (γ, between 0 and 90), curved wall aspect ratio (AR, between 01. and 1.2), power law index (n, between 0.8 and 1.2), nanoparticle volume fraction (ϕ, between 0 and 0.04) and particle size in nm (dp, between 20 and 80). The amount of rise in average Nusselt (Nu) number with Re number depends upon the power law index while the discrepancy between the Newtonian fluid case becomes higher with higher values of power law indices. As compared to case with n = 1, discrepancy in the average Nu number are obtained as −38% and 71.5% for cases with n = 0.8 and n = 1.2. The magnetic field strength and inclination can be used to control the size and number or vortices. As magnetic field is imposed at the higher strength, the average Nu reduces by about 26.6% and 7.5% for single and double jets with n greater than 1 while it increases by about 4.78% and 12.58% with n less than 1. The inclination of magnetic field also plays an important role on the amount of enhancement in the average Nu number for different n values. The aspect ratio of the curved wall affects the flow field slightly while the average Nu variation becomes 5%. Average Nu number increases with higher solid particle volume fraction and with smaller particle size. At the highest particle size, it is increased by about 14%. There is 7% variation in the average Nu number when cases with lowest and highest particle size are compared. Finally, convective heat transfer performance modeling with four inputs and one output is successfully obtained by using Adaptive Neuro-Fuzzy Interface System (ANFIS) which provides fast and accurate prediction results.

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