Τετάρτη, 25 Ιουλίου 2007

Journal of Forensic Sciences/ July 2007

Κυκλοφόρησε το νέο τεύχος του Journal of Forensic Sciences (JOFSC), Volume 52, Number 4, July 2007. Ακολουθούν τα περιεχόμενά που αφορούν τηε Δικαστική Γραφολογία:

The new issue of the Journal of Forensic Sciences (JOFSC), Volume 52, Number 4, July 2007 has been released.Here are the contents of the articles concerning Questioned Documents:

  • D.L.Hammond: Validation of LAB color mode as Nondestructive Method to differentiate Black Ballpoint Pen Inks (pp.967)
  • S.Sugawara: Passport Examination by Polarized Infrared Spectrum (pp. 974)



Passport Examination by Polarized Infrared Spectra

Abstract: In this study, a new nondestructive technique for passport examination is proposed. In this technique, linearly polarized light is used to measure Fourier transform infrared (FT-IR) reflectance spectra of films on the biographical data page. Thirty genuine and thirty-five counterfeit Japanese passports and five marketed films pasted on name cards were examined. The measured spectra were analyzed as follows. The absorption spectra were obtained by the Kramers–Kronig transformations of reflectance spectra. The peak ratios were then calculated from the absorption spectra by adding the peak areas at 1126 and 1263 cm1 and dividing the result by the peak area at 1727 cm1. When nonpolarized light was used, the samples could not be distinguished by comparing the peak ratios. However, when polarized light was used, they were successfully distinguished by the comparison. Therefore, polarized light is useful for the forensic discrimination of passport films by the measurement of FT-IR spectra.

Validation of LAB Color Mode as a Nondestructive Method to Differentiate Black Ballpoint Pen Inks

Abstract: Nondestructive digital processing methods such as lab color mode (available in Adobe® Photoshop®) are emerging as alternative methods for forensic document examiners to use when attempting to differentiate writing instrument inks. Although these techniques appear to be viable, little data currently exists regarding the known or potential error rates associated with these techniques. Without adequate data, the validity and reliability of these techniques, including lab color, can not be established. In an attempt to begin to address these issues, 44 black ballpoint ink pens were obtained and used to create 990 pen-pair samples for analysis using established lab color mode techniques. No erroneous findings of "different" were reported following the examination of the known pen-pair combinations in which the same pen was used to create the samples (n = 44). Of the remaining 946 samples, 737 pen-pair samples were differentiated using the lab color mode method, while 209 samples were unable to be differentiated and were recorded as either being "similar" (n = 153) or "unsure" (n = 56). Comparison of the lab color mode results with the results obtained through additional testing using traditional infrared reflectance and infrared luminescence test methods showed that lab color differentiated 102 pen-pair samples (11%; 102/946) that were not differentiated using a VSC-4C.

Σάββατο, 21 Ιουλίου 2007

New Ink Sampling Technique Taking A Bite Of Out Time

Source: DOE/Ames Laboratory Date: July 19, 2007

Science Daily — Primetime crime drama meets reality in forensic research taking place at the Midwest Forensics Resource Center at Iowa State University. US Department of Ames Laboratory scientists are using the new Direct Analysis in Real Time mass spectrometry interface, which has made a guest appearance on the popular crime show "CSI: New York," to build a library of ink mass spectra using samples from the US Secret Service. The mass spectra library will help identify inks on fraudulent documents and other crime evidence.

Researchers at the Midwest Forensics Resource Center at Iowa State University are building a library of ink profiles to help forensic scientists identify inks on fraudulent documents and other evidence. MFRC scientists will pair mass spectrometry with a new sampling technique called Direct Analysis in Real Time (DART) to reveal the chemical makeup of ink faster and in greater detail than ever before.
DART mass spectrometry analyzes ink by creating a stream of warm gas containing excited-state helium atoms or nitrogen molecules in the DART source. The gas stream is pointed at an ink sample, and the gas and excited-state species evaporate and ionize molecules from the sample. A mass spectrometer measures the production of ions to create mass spectrum data for each ink sample tested.
In contrast to other types of ink analysis, like liquid chromatography, which require cutting a small sample from a questioned document, DART mass spectrometry is able to test documents without physically or visually altering them. The questioned document is open to the environment, and all sizes of materials may be tested in their original form.
According to Roger Jones, U.S Department of Energy's Ames Laboratory associate chemist, "The great thing about the DART system is that it can sample the ink straight off the paper. You don't have to extract a sample first. Before DART, we had to cut a little bit of sample out and dissolve it in solvent for analysis. So, now we can look at the document without visibly altering it, which is good for forensic science. We don't destroy the evidence."
Eliminating the sampling extraction process saves busy forensic scientists time. Jones said that benefit alone would have been enough to consider the DART method a success.
"We would have been satisfied with the mass spectra looking basically like the spectra obtained by the old extraction mass spectrometry methods, because the DART system still gets around damaging the sample and reduces the work involved in analysis," said Jones, "Time constraints are the major complaint of every forensic scientist. Their caseloads are so large that they just don't have the time to do traditional ink analysis."
But, on top of saving time and preserving evidence, the DART method also yields richer data about ink samples than previous sampling methods. Initial tests of the DART system indicate that the mass spectra reveal more components of the ink than conventional mass spectra. Using DART, forensic scientists may be able to differentiate between inks like never before.
Jones and John McClelland, Ames Laboratory senior physicist and DART project leader, plan a three-phase project. Currently in the first phase, they are experimenting to determine the best way to analyze inks and build the library.
The library of ink mass spectra will be produced in the second phase of the project. Researchers will use samples from the U.S. Secret Service International Ink Library to create a comprehensive, vetted, and computer searchable library of mass spectra of the more than 8,000 inks the Secret Service has compiled.
The third phase of the project will focus on creating computer software used to store and access the mass spectra library.
"Commercial mass spectrometry software available today is all based on the old style of mass spectrometry. We get a different type of data from DART. So, the assumptions used in existing software for searching and matching mass spectra do not work the best for DART," said Jones.
The U.S. Department of Justice's National Institute of Justice is funding the project.
Note: This story has been adapted from a news release issued by DOE/Ames Laboratory.


Δευτέρα, 16 Ιουλίου 2007

Journal of the American Society of Questioned Document Examiners/ June 2007

Κυκλοφόρησε το νέο τεύχος του Journal of the American Society of Questioned Document Examiners (JASQDE), Volume 10, Number 1, June 2007.

Ακολουθούν τα περιεχόμενά του:

The new issue of the Journal of the American Society of Questioned Document Examiners (JASQDE), Volume 10, Number 1, June 2007 has been released.

Here are the contents:

  1. C.R.McClary: Design & Security Features of the Euro
  2. T.A.Tanaka: Voltage & Identation Development
  3. W.D.Mazzella & R.Marquis: Forensic Image Analysis of Laser-Printed Documents
  4. J.L.Streeter, G.P.Kettering & K.B.Zercie: Invisible Ink: A Refresher for Document Examiners
  5. Y-S P. Cheng: A study on the influence of wearing a glove on handwriting by chinese in Hong Kong.

Δευτέρα, 2 Ιουλίου 2007

Τεχνητό ανθρώπινο χέρι/ Robotic Human Hand

Εταιρία ρομποτικής στην Ιαπωνία παρουσίασε το πρωτότυπο ενός τεχνητού ανθρώπινου χεριού το οποίο λειτουργεί με πεπιεσμένο αέρα και μπορεί να εκτελεί λεπτές κινήσεις, όπως το να πιάνει ένα στιλό. Η εταιρεία Squse με έδρα το Κιότο, η οποία ειδικεύεται στα ρομπότ και σε συστήματα αυτοματισμού εργοστασίων, παρουσίασε ένα μηχανικό χέρι με πέντε δάχτυλα, βάρους 400 γραμμαρίων, το οποίο κινείται με τεχνητές μυϊκές ίνες που ελέγχονται με την πίεση του αέρα. Πενήντα τέτοια χέρια θα αποσταλούν σε ξένα ερευνητικά ινστιτούτα και εταιρίες. Η τεχνολογία είναι πολύ πιθανό να αξιοποιηθεί και εμπορικά μέσα στην επόμενη πενταετία.

A japanese robotics company introduced a prototype of a robotic human hand, that operates using condensed air, and that can carry out delicate movements, like holding a pen. Squse company, in Kyoto, which specializes in robots and laboratory automation systems, introduced the mechanical arm with five fingers, weighting 400 gr, that can move with technical muscles controlled by air pressure. 50 such hands will be sent to foreign research institutes and companies. This technology is probably going to be used commercially in the following 5 years.

skai.gr 28/06/2007 http://www.skai.gr/master_story.php?id=52461