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Mass-producible micro-holographic tags

Description: Microtags are microscopic computer-generated holograms with 130-nm features and are mass-producible with EUVL. This fabrication method renders microtags difficult to counterfeit. Applications includ tagging and tracking of microprocessors, memory chips, currencey, and credit cards.
Date: June 1, 1996
Creator: Sweatt, W.C.; Ray-Chaudhuri, A.K.; Kravitz, S.H.; Warren, M.E.; Stulen, R.H.; Tichenor, D.A. et al.
Partner: UNT Libraries Government Documents Department

UTag: Long-range Ultra-wideband Passive Radio Frequency Tags

Description: Long-range, ultra-wideband (UWB), passive radio frequency (RF) tags are key components in Radio Frequency IDentification (RFID) system that will revolutionize inventory control and tracking applications. Unlike conventional, battery-operated (active) RFID tags, LLNL's small UWB tags, called 'UTag', operate at long range (up to 20 meters) in harsh, cluttered environments. Because they are battery-less (that is, passive), they have practically infinite lifetimes without human intervention, and they are lower in cost to manufacture and maintain than active RFID tags. These robust, energy-efficient passive tags are remotely powered by UWB radio signals, which are much more difficult to detect, intercept, and jam than conventional narrowband frequencies. The features of long range, battery-less, and low cost give UTag significant advantage over other existing RFID tags.
Date: March 14, 2007
Creator: Dowla, F.
Partner: UNT Libraries Government Documents Department

Analysis of wolves and sheep. Final report

Description: In evaluating speaker verification systems, asymmetries have been observed in the ease with which people are able to break into other people`s voice locks. People who are good at breaking into voice locks are called wolves, and people whose locks are easy to break into are called sheep. (Goats are people that have a difficult time opening their own voice locks.) Analyses of speaker verification algorithms could be used to understand wolf/sheep asymmetries. Using the notion of a ``speaker space``, it is demonstrated that such asymmetries could arise even though the similarity of voice 1 to voice 2 is the same as the inverse similarity. This explains partially the wolf/sheep asymmetries, although there may be other factors. The speaker space can be computed from interspeaker similarity data using multidimensional scaling, and such speaker space can be used to given a good approximation of the interspeaker similarities. The derived speaker space can be used to predict which of the enrolled speakers are likely to be wolves and which are likely to be sheep. However, a speaker must first enroll in the speaker key system and then be compared to each of the other speakers; a good estimate of a person`s speaker space position could be obtained using only a speech sample.
Date: August 1, 1997
Creator: Hogden, J.; Papcun, G.; Zlokarnik, I. & Nix, D.
Partner: UNT Libraries Government Documents Department

Simulated NMIS Imaging Data for an Unknown Object

Description: This report presents simulated Nuclear Materials Identification System (NMIS) imaging data for an unclassified object, whose characteristics are initially unknown to the reader. This data will be used to test various analysis capabilities and was created with a simple deterministic ray-tracing algorithm. NMIS is a time-dependent coincidence counting system that is used to characterize both fissile and non-fissile materials undergoing nondestructive assay. NMIS characterizes materials by interrogating them with neutrons, either from an associated-particle deuterium-tritium (DT) neutron generator, which produces a time and directionally tagged monoenergetic beam of 14.1 MeV neutrons, or a time-tagged spontaneous fission source in an ionization chamber.
Date: April 1, 2012
Creator: Walker, Mark E & Mihalczo, John T
Partner: UNT Libraries Government Documents Department

Use and Misuse of Chemical Reactivity Spreadsheets

Description: Misidentifying chemical hazards can have serious deleterious effects. Consequences of not identifying a chemical are obvious and include fires, explosions, injury to workers, etc. Consequences of identifying hazards that are really not present can be equally as bad. Misidentifying hazards can result in increased work with loss of productivity, increased expenses, utilization/consumption of scarce resources, and the potential to modify the work to include chemicals or processes that are actually more hazardous than those originally proposed. For these reasons, accurate hazard identification is critical to any safety program. Hazard identification in the world of chemistry is, at best, a daunting task. The knowing or understanding, of the reactions between any of approximately twelve million known chemicals that may be hazardous, is the reason for this task being so arduous. Other variables, such as adding other reactants/contaminants or changing conditions (e.g., temperature, pressure, or concentration), make hazard determination something many would construe as being more than impossibly difficult. Despite these complexities, people who do not have an extensive background in the chemical sciences can be called upon to perform chemical hazard identification. Because hazard identification in the area of chemical safety is so burdensome and because people with a wide variety of training are called upon to perform this work, tools are required to aid in chemical hazard identification. Many tools have been developed. Unfortunately, many of these tools are not seen as the limited resource that they are and are used inappropriately.
Date: September 20, 2005
Creator: Simmons, F
Partner: UNT Libraries Government Documents Department

Multipurpose locator tag system : LDRD 65145 final report.

Description: This report summarizes work performed to determine the capability of the Pinpoint Locator system, a commercial system designed and manufactured by RF Technologies. It is intended for use in finding people with locator badges in multi-story buildings. The Pinpoint system evaluated is a cell-based system, meaning it can only locate badges within an area bordered by its antennas.
Date: November 1, 2003
Creator: Greenway, Douglas Jr. & Schuster, Gary R.
Partner: UNT Libraries Government Documents Department

The Effect of Neutron and Gamma Ray Cross Talk Between Plastic Scintillating Detectors

Description: In this paper a method is developed, using higher order statistics, to identify the type and degree of neutron and gamma ray cross talk between detectors that are placed in proximity to one another. A set of measurements was performed using the Nuclear Materials Identification System (NMIS) to acquire the time-dependent bicovariance of the pulses in fast plastic scintillating detectors. These signatures were analyzed to infer the degree and type of false coincidences (cross talk) in relation to true coincidences.
Date: November 6, 2000
Creator: Pozzi, S.A.
Partner: UNT Libraries Government Documents Department

Impedance Noise Identification for State-of-Health Prognostics

Description: Impedance Noise Identification is an in-situ method of measuring battery impedance as a function of frequency using a random small signal noise excitation source. Through a series of auto- and cross-correlations and Fast Fourier Transforms, the battery complex impedance as a function of frequency can be determined. The results are similar to those measured under a lab-scale electrochemical impedance spectroscopy measurement. The lab-scale measurements have been shown to correlate well with resistance and power data that are typically used to ascertain the remaining life of a battery. To this end, the Impedance Noise Identification system is designed to acquire the same type of data as an on-board tool. A prototype system is now under development, and results are being compared to standardized measurement techniques such as electrochemical impedance spectroscopy. A brief description of the Impedance Noise Identification hardware system and representative test results are presented.
Date: July 1, 2008
Creator: Christophersen, Jon P.; Motloch, Chester G.; Morrison, John L.; Donnellan, Ian B. & Morrison, William H.
Partner: UNT Libraries Government Documents Department

Large Spectral Library Problem

Description: Hyperspectral imaging produces a spectrum or vector at each image pixel. These spectra can be used to identify materials present in the image. In some cases, spectral libraries representing atmospheric chemicals or ground materials are available. The challenge is to determine if any of the library chemicals or materials exist in the hyperspectral image. The number of spectra in these libraries can be very large, far exceeding the number of spectral channels collected in the ¯eld. Suppose an image pixel contains a mixture of p spectra from the library. Is it possible to uniquely identify these p spectra? We address this question in this paper and refer to it as the Large Spectral Library (LSL) problem. We show how to determine if unique identi¯cation is possible for any given library. We also show that if p is small compared to the number of spectral channels, it is very likely that unique identi¯cation is possible. We show that unique identi¯cation becomes less likely as p increases.
Date: October 3, 2008
Creator: Chilton, Lawrence K. & Walsh, Stephen J.
Partner: UNT Libraries Government Documents Department

Bartus Iris biometrics

Description: This is the final report of a one-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). We won a 1994 R&D 100 Award for inventing the Bartas Iris Verification System. The system has been delivered to a sponsor and is no longer available to us. This technology can verify the identity of a person for purposes of access control, national security, law enforcement, forensics, counter-terrorism, and medical, financial, or scholastic records. The technique is non-invasive, psychologically acceptable, works in real-time, and obtains more biometric data than any other biometric except DNA analysis. This project sought to develop a new, second-generation prototype instrument.
Date: July 1, 1996
Creator: Johnston, R. & Grace, W.
Partner: UNT Libraries Government Documents Department

Hand geometry field application data analysis

Description: Over the last fifteen years, Sandia National Laboratories Security Systems and Technology Center, Department 5800, has been involved in several laboratory tests of various biometric identification devices. These laboratory tests were conducted to verify the manufacturer`s performance claims, to determine strengths and weaknesses of particular devices, and to evaluate which devices meet the US Department of Energy`s unique needs for high-security devices. However, during a recent field installation of one of these devices, significantly different performance was observed than had been predicted by these laboratory tests. This report documents the data analysis performed in the search for an explanation of these differences.
Date: March 1, 1997
Creator: Ruehle, M. & Ahrens, J.
Partner: UNT Libraries Government Documents Department

Plastic-casting intrinsic-surface unique identifier (tag)

Description: This report describes the development of an authenticated intrinsic-surf ace tagging method for unique- identification of controlled items. Although developed for control of items limited by an arms control treaty, this method has other potential applications to keep track of critical or high-value items. Each tag (unique-identifier) consists of the intrinsic, microscopic surface topography of a small designated area on a controlled item. It is implemented by making a baseline plastic casting of the designated tag area and usually placing a cover (for example, a bar-code label) over this area to protect the surface from environmental alteration. The plastic casting is returned to a laboratory and prepared for high-resolution scanning electron microscope imaging. Several images are digitized and stored for use as a standard for authentication of castings taken during future inspections. Authentication is determined by numerically comparing digital images. Commercially available hardware and software are used for this tag. Tag parameters are optimized, so unique casting images are obtained from original surfaces, and images obtained from attempted duplicate surfaces are detected. This optimization uses the modulation transfer function, a first principle of image analysis, to determine the parameters. Surface duplication experiments confirmed the optimization.
Date: April 1, 1995
Creator: Palm, R.G. & De Volpi, A.
Partner: UNT Libraries Government Documents Department

Remote secure proof of identity using biometrics

Description: Biometric measurements derived from finger- or voiceprints, hand geometry, retinal vessel pattern and iris texture characteristics etc. can be identifiers of individuals. In each case, the measurements can be coded into a statistically unique bit-string for each individual. While in electronic commerce and other electronic transactions the proof of identity of an individual is provided by the use of either public key cryptography or biometric data, more secure applications can be achieved by employing both. However the former requires the use of exact bit patterns. An error correction procedure allows us to successfully combine the use of both to provide a general procedure for remote secure proof of identity using a generic biometric device. One such procedure has been demonstrated using a device based on hand geometry.
Date: June 10, 1997
Creator: Sengupta, S. K.; Pearson, P. & Strait, R.S.
Partner: UNT Libraries Government Documents Department

Digitally Marking RSA Moduli

Description: The moduli used in RSA (see [5]) can be generated by many different sources. The generator of that modulus (assuming a single entity generates the modulus) knows its factorization. They would have the ability to forge signatures or break any system based on this moduli. If a moduli and the RSA parameters associated with it were generated by a reputable source, the system would have higher value than if the parameters were generated by an unknown entity. So for tracking, security, confidence and financial reasons it would be beneficial to know who the generator of the RSA modulus was. This is where digital marking comes in. An RSA modulus ia digitally marked, or digitally trade marked, if the generator and other identifying features of the modulus (such as its intended user, the version number, etc.) can be identified and possibly verified by the modulus itself. The basic concept of digitally marking an RSA modulus would be to fix the upper bits of the modulus to this tag. Thus anyone who sees the public modulus can tell who generated the modulus and who the generator believes the intended user/owner of the modulus is.
Date: October 9, 2000
Creator: Johnston, A. M.
Partner: UNT Libraries Government Documents Department

Aerogel Fingerprint Media

Description: A fingerprint medium which is made of an aerogel having a predetermined density. The fingerprint medium may have a midrange density for forming plates or may be crushed forming a powder. The fingerprint medium may further include at least one of a metal and metal oxide to enhance characteristics desirable in a fingerprint medium.
Date: September 21, 1999
Creator: Miller, Fred S. & Andresen, Brian D.
Partner: UNT Libraries Government Documents Department

Tagging of Isobars Using Energy Loss and Time-of-flight Measurements

Description: The technique for tagging isobars in a mixed beam by measuring energy loss by time-of-flight has been tested. With this method, isobar separation should improve by allowing more energy loss (thicker absorber), but only if one can control absorber homogeneity. Measurements of beam energy toss and energy spread obtained under such conditions were shown to be close to predicted values using both collisional and charge exchange contributions to energy straggling. The calculation of energy straggling allows us to study the efficacy of this method for isobar separation when applied to different mass ranges and beam energies. Separation in a most difficult case, an analyzed beam of A = 132 isobars at energies near 3 MeV/A has been demonstrated. The time-of-flight information can be added on line as an additional tag to the data stream for events of interest. Such event by event tagging enables one to study the effect of differences in isobaric mixture in the beam on the reaction outcome even when isobar separation is not complete.
Date: November 2, 2001
Creator: Shapira, D.
Partner: UNT Libraries Government Documents Department

Damage detection for applications undergoing axial (membrane) response

Description: This paper extends and applies recently reported damage identification methods, previously utilized for flexural vibrations only, to axial-type vibrations. The methods are applied to an 8-DOF linear spring-mass system, which models a multi-degree-of-freedom axial or membrane system. The goal of the work is to detect damage (as indicated by reduction in stiffness of one or more of the elements) as well as to locate the damage elements. Two damage detection methods were investigated--the change-in-flexibility method and the damage-index method. Both were found to successfully locate the damaged element(s) for 10% reduction in element stiffness. The change-in-flexibility method indicated damage location even when only a limited number of lower modes were included.
Date: December 1, 1997
Creator: Duffey, T.A.; Farrar, C.R. & Doebling, S.W.
Partner: UNT Libraries Government Documents Department

On enabling secure applications through off-line biometric identification

Description: In developing secure applications and systems, the designers often must incorporate secure user identification in the design specification. In this paper, the authors study secure off line authenticated user identification schemes based on a biometric system that can measure a user`s biometric accurately (up to some Hamming distance). The schemes presented here enhance identification and authorization in secure applications by binding a biometric template with authorization information on a token such as a magnetic strip. Also developed here are schemes specifically designed to minimize the compromise of a user`s private biometrics data, encapsulated in the authorization information, without requiring secure hardware tokens. In this paper the authors furthermore study the feasibility of biometrics performing as an enabling technology for secure system and application design. The authors investigate a new technology which allows a user`s biometrics to facilitate cryptographic mechanisms.
Date: April 1, 1998
Creator: Davida, G.I.; Frankel, Y. & Matt, B.J.
Partner: UNT Libraries Government Documents Department