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This module discusses the procedure of our research project and outcomes.

Whole painting analysis and results

Step 1: obtain the raw data

We received x-ray images of paintings from the Van Gogh Museum of Amsterdam. Images usually sampled at 600. Figure 1 shows the x-ray image of Van Gogh’s Backyards of Old Houses in Antwerp in the Snow (F260) provided by the Van Gogh Museum.

Step 2: short time fourier analysis

We apply shot time Fourier analysis for each 0.5” × 0.5” swatch. We discarded the outrange frequency peaks and set the value as NaN for the corresponding swatches. For multiple peaks in the frequency region of interest, we accepted the peak that is closest to the median value.

Step 3: spectra of whole-painting

We sampled the short-space spectrum every 1/4” in both directions (horizontal and vertical) for the whole-painting by choosing swatches overlap each other by half in each direction. Thus the spectra of whole-painting were obtained. And we could determine the warp and weft direction of the canvas according to the spread of measurements. Calculations were made in Matlab and took about three hours to analyze F205 on a laptop computer.

Figure 2 shows the resulting spectra of F205.

Step 4: deviations matching analysis

From the spectra of the whole-painting, we obtained thread count deviations spectra by calculating the distributions of frequencies and subtracting the averages.

Figure 3 and 4 show the vertical thread count deviations of F205 and F260 respectively. Horizontal deviations spectra are not shown here.

Visually, we can see the matching strips between these two painting. But how well do they match?

Step 5: 2d to 1d conversion

We first computed the 1D thread count deviations from the 2D data. The 1D thread count deviations are obtained by summing the column deviations of 2D data while discarding all the NaNs if any.

Figure 5 and 6 are the corresponding 1D plot of F205 and F260.

We can clearly see the similarities now. But how do they correlate then?

Step 6: correlation determination

We then computed unbiased correlation coefficient between 1D vertical thread count deviations of F205 and F260 along the x-axis. You can clearly see a peak (0.7479) appears at the 55th alignment as two paintings are mapped to the matching alignment, or visually “best fit” together. The correlation mapping plot is shown in figure 7.

The results indicate that these two paintings (F205 and F260) were likely cut from the same canvas roll, sharing the more variable weft direction.

Orientation issues in matching

When we computed the correlation for the paintings, we actually did it four times in our Matlab programs. This is because that any two paintings could possibly match in either direction and each painting could be rotated 0, 90 or 180 degree.

In plotting the correlation mapping, we choose the one that gave the best fit among all possible orientations.

Questions & Answers

where we get a research paper on Nano chemistry....?
Maira Reply
what are the products of Nano chemistry?
Maira Reply
There are lots of products of nano chemistry... Like nano coatings.....carbon fiber.. And lots of others..
learn
Even nanotechnology is pretty much all about chemistry... Its the chemistry on quantum or atomic level
learn
Google
da
no nanotechnology is also a part of physics and maths it requires angle formulas and some pressure regarding concepts
Bhagvanji
Preparation and Applications of Nanomaterial for Drug Delivery
Hafiz Reply
revolt
da
Application of nanotechnology in medicine
what is variations in raman spectra for nanomaterials
Jyoti Reply
I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
Damian
yes that's correct
Professor
I think
Professor
Nasa has use it in the 60's, copper as water purification in the moon travel.
Alexandre
nanocopper obvius
Alexandre
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
Rafiq
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
Damian
How we are making nano material?
LITNING Reply
what is a peer
LITNING Reply
What is meant by 'nano scale'?
LITNING Reply
What is STMs full form?
LITNING
scanning tunneling microscope
Sahil
how nano science is used for hydrophobicity
Santosh
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
Rafiq
what is differents between GO and RGO?
Mahi
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
Rafiq
if virus is killing to make ARTIFICIAL DNA OF GRAPHENE FOR KILLED THE VIRUS .THIS IS OUR ASSUMPTION
Anam
analytical skills graphene is prepared to kill any type viruses .
Anam
Any one who tell me about Preparation and application of Nanomaterial for drug Delivery
Hafiz
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
Bob
The nanotechnology is as new science, to scale nanometric
brayan
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Damian
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
Renato
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
Adin
why?
Adin
what school?
Kyle
biomolecules are e building blocks of every organics and inorganic materials.
Joe
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Frequency analysis for art forensics. OpenStax CNX. Jan 22, 2009 Download for free at http://cnx.org/content/col10632/1.1
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