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Ian Bailey

Bio:


2019. B.S. Mathematics, Indiana University


Project Info:


  • TITLE:
    Measuring the Performance of Likelihood-Ratio-Based Systems

  • ABSTRACT:

    In forensic science, the probative value of evidence is often quantified using likelihood ratios (LRs), but yet, there are still difficulties when it comes to assigning LRs with the appropriate magnitude. This work focuses on a specific property of LRs and how it can be useful in assessing the calibration of models and systems that assign LRs. Moreover, this work includes an analysis of a proposed tool for measuring the performance of a system that produces LRs: the Empirical Cross-Entropy (ECE) Plot. We find that this tool is very effective in assessing the performance of LR-based systems, but that it is inappropriate to use it to compensate for poorly designed models. Our results attempt to shed light on potential solutions to the difficulties that exist in a forensic scientist’s assessment of evidence, namely the quality of LRs that are produced from that evidence.

  • Project Report is not yet available.
  • Poster


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Brandon Barker

Bio:


2017 B.S. Computer Science, Boise State University


Project Info:


  • TITLE:
    An Investigation into Manifold Learning Techniques and Biometric Face Registration for User Authentication

  • ABSTRACT:

    From law enforcement to private corporations, facial recognition technology is becoming more commonly used. Unfortunately, correctly identifying a face in imperfect conditions using this technology continues to prove challenging. This work investigates manifold learning techniques applied to facial image variation across scale, registration, planar rotation, and projective skew.  The goals of the research are to gain useful insight into the manifold structure both geometrically and heuristically.  Several manifold examples are presented using a projection from high-dimensional image space to a 3-dimensional subspace computed using principal components.  It is shown that regardless of the individual under consideration, the manifold embedding for each variation remains geometrically and heuristically similar.

  • Project Report is not yet available.
  • Poster


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Natalie Boykoff

Bio:


2018 B.S. New York University, Chemical Engineering


Project Info:


  • TITLE:
    Optimization of the Cyanalyzer by Defining Maximum Sample Volume, Testing Durability of Adhesive, and Evaluating Micro-Solenoids

  • ABSTRACT:

    Cyanide (CN-) is a deadly chemical weapon, an essential reagent for chemical industries and research labs and a toxin produced from house fires. The ion inhibits the cytochrome c oxidase enzyme, preventing the conversion of oxygen and halting the synthesis of ATP. Currently, the Cyanalyzer is the first of its kind to be able to successfully detect cyanide exposure rapidly and sensitively through acidifying a cyanide spiked rabbit blood sample (15 microL) with water (80 microL) and sulfuric acid (200 microL) to produce cyanide gas. Within the capture chamber, HCN gas reacts with naphthalene dialdehyde (NDA) (220 microL), taurine (220 microL) and NaOH base solution (220 microL) to yield a fluorescent b-isoindole product3. The objective for this research was to establish a maximum sample chamber capacity before overflow occurs, confirm the strength of the bubble adhesive, and assess the efficiency of solenoids for reagent delivery in comparison to the current linear actuators.  The maximum sample chamber volume was determined by increasing the volume of water until it consistently overflowed into the capture chamber. An addition of 80-95 mL of water produced no overflow. The durability of the bubble adhesive was tested two ways: 1) filling bubbles with various solutions and allowing them to rest for a week, and 2) filling bubbles with various solutions and depressing them 50 times. The integrity of the bubbles was maintained during each experiment, indicating that the adhesive was appropriate for the projected one-time use cartridge. The utility of electromagnetic solenoids was evaluated for depressing reagent bubbles and to discharge the cartridge from cartridge holder. The solenoids succeeded in depressing the bubbles with an even, ample force, without breaking them and lifted the cartridge from holder a height sufficient for manual removal. Based on these results, the risk of false positives has been greatly reduced by defining the maximum sample volume, the strength of the bubble adhesive was verified and the solenoid’s reagent delivery was found relative to current linear actuator’s.

  • Project Report is not yet available.
  • Poster


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Khadijah Cessac

Bio:


2017 B.S. Chemistry, Southern University


Project Info:


  • TITLE:
    The Dispersion Stability of Upconverting Nanoparticle Inks

  • ABSTRACT:

    Upconverting nanoparticles (UCNP) in ink formulation are on the rise in the realm of security printing and anti-counterfeiting. Being knowledgeable about the ink’s stability and behavior under certain conditions is important because it allows scientists and companies to continuously learn key aspects to bettering ink formulations. In order for these inks to be used commercially in security printing certain boundaries and expectations must be met. For example, most companies lean towards water-based inks because they are easy to produce, are environmentally friendly, and most importantly, are cost effective. While the advantages of upconverting inks are quite beneficial, there is little literature on stability testing of these inks. Therefore, the purpose of this research was to first formulate a water based ink that had a surface tension and suitable viscosity for printing purposes and then create a method to determine the stability of UCNP inks.  The ending formulation contained 85% water, 15% glycerin, by volume, and 0.2 wt% sodium dodecyl sulfate (SDS). The surface tension of this base was approximately 40-41 mN/m and 1.0 cP in viscosity. The stability testing included a continuation of surface tension and viscosity testing, and also a weight analysis of 0.3 wt% and 0.6 wt% nanoparticle ink in three storage conditions: cool, warm (60 °C), and ambient temperatures. To further analyze the observed values, comparison to TGA results was used as a reference.

  • Project Report is not yet available.
  • Poster


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Jake Deutz

Bio:


2018 B.S. South Dakota School of Mines and Technology, Electrical Engineering


Project Info:


  • TITLE:
    Upconverting Nano Particle Reader

  • ABSTRACT:

    The International Chamber of Commerce projected that the global value of counterfeit goods climbed to a staggering $1.8 trillion in 2015, a three-fold increase from 2008. Thus, it is important to develop new ways to counteract the threat. It has been shown that upconverting nanoparticle inks are a good method to mark products for authentication purposes. A near infrared laser is used to cause the inks to upconvert to either visible or a different wavelength of near infrared. The purpose of this study is to further develop an existing  system (laser/optics/camera) that reads quick response (QR) codes printed with upconverting nanoparticle inks. The goal of this research is to make a more stable system and to redesign the laser system housing to make the system more portable.

  • Project Report is not yet available.
  • Poster


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Dustin Gansebom

Bio:


2018 B.S. Truman State University, Chemistry


Project Info:


  • TITLE:
    Colloidal Stability of Hydrophilically Modified β-NaYF4 Nanocrystals

  • ABSTRACT:

    Upconversion nanocrystals, which emit light of a shorter wavelength than they absorb, have become the subject of much research in recent years.  So far, the most efficient upconverters known are β-NaYF4 nanocrystals, and many different methods have been used to synthesize them.  The majority of these synthetic routes, or at least the most successful ones, have used nonpolar capping ligands.  As a result, the as-synthesized β-NaYF4 nanocrystals are only dispersible in nonpolar media, not water.  This limitation of the synthetic procedure severely limits the potential applications of said nanocrystals, many of which require dispersions in aqueous media.  Altering the surface chemistry of as-synthesized hydrophobic nanocrystals is a promising method for overcoming this restriction and rendering a variety of different nanocrystals dispersible in water.  In this study, oleic acid capped β-NaYF4 nanocrystals will be hydrophilically modified by using oleic acid (OLA) and poly(maleic anhydride-alt-1-octadecene) (PMAO) to form a bilayer on the nanocrystal surface.  The effect of crosslinking the PMAO bilayer with bis(6-aminohexyl)amine (BAHA) will also be examined.  Furthermore, the stability of the resulting aqueous colloids will be analyzed with Dynamic Light Scattering (DLS) and ζ-potential measurements.  The presence and quality of the bilayers formed will also be determined via FTIR analysis and electron microscopy.

    It was found that β-NaYF4 nanocrystals did not form stable colloids when hydrophilically modified with an oleic acid bilayer; however, the nanocrystals that were modified with a PMAO bilayer were found to form moderately stable colloids.

  • Project Report is not yet available.
  • Poster


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Lance Kotter

Bio:


2017 B.S. University of Jamestown, Chemistry


Project Info:


  • TITLE:
    Real Time Spectroscopic Monitoring of the Synthesis of core/shell β-NaYF4 Nanocrystals

  • ABSTRACT:

    Real-time spectroscopic monitoring (RTM) of luminescence is applied to study the reaction mechanism of the synthesis of the core -NaYF4:17% Yb, 3% Er nanocrystals and also the shell addition to that core. The shell material consists either of spectroscopically inert -NaYF4 or spectroscopically active -NaYF4:10% Yb, 10% Nd. The advantage of using RTM is to precisely time the various stages of the reaction, show the transition between those stages, and accurately define when the reaction has gone to completion. The core nanocrystals are formed by a variation of co-precipitation method that is often referred to as heat-up method. There are three stages that occur during the core synthesis.  The first stage involves the formation of small -phase nanoparticles, the second is a stasis period with little to no change, and the third is the rapid transition from -phase nanoparticles to much larger -phase nanoparticles. A shell can then be added in order to increase luminescence efficiency by reducing surface quenching.  So-called active shells can also enable excitation of luminescence at an alternative wavelength. The shell is added by combining the core particles with small -phase particles of the desired shell material in a high-boiling-point solvent system and then heating the mixture. Shell addition is also monitored spectroscopically in order to understand the kinetics of the reaction and to determine when the addition is completed.

  • Project Report is not yet available.
  • Poster


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Abigail McBride

Bio:


2018 B.S. South Dakota School of Mines and Technology, Metallurgical Engineering


Project Info:


  • TITLE:
    Porous-Wall Hollow Glass Microspheres for Security Ink Applications

  • ABSTRACT:

    Copper oxide loaded porous-wall hollow glass microspheres (PWHGMs) are a possible functional material system for anti-tamper security inks. The method currently used to load PWHGMs with copper oxide allows copper oxide to form on both the interior and exterior surfaces, as well as within the wall porosity. The undesired presence of copper oxide on the surface and within the wall porosity hinders multiple loadings and limits anti-tamper functionality. We report a new loading method that increases loading effectiveness by incorporating a leaching process to remove surface copper oxide. Leaching process development was conducted using copper oxide formed on glass slides and solid wall glass microspheres. It was found that the copper oxide crystals formed in the loading process can be leached in 0.5 M hydrochloric acid. The final cleaning method was evaluated using PWHGMs. PWHGMs obtained from the Applied Research Center in South Carolina were loaded with copper chloride precursor solution under negative pressure and subsequently heat treated at 450oC in an air furnace to promote copper oxide formation. It was confirmed that soaking loaded PWHGMs in 0.5 M hydrochloric acid is a viable method for cleaning surface copper oxide. Furthermore, this cleaning method is effective in improving copper oxide loading efficiency, whereby hydrochloric acid cleaning between initial loading and secondary loading resulted in a 654% increase in average copper oxide crystal sizes within PWHGMs compared to samples without cleaning. Optical imaging of a loaded sphere was conducted to explore an alternative copper oxide crystal detection method. It was also found that optical imaging is a possible non-destructive method for determining the presence of interior copper oxide crystals. Hyperspectral imaging was also conducted to evaluate the possible spectral response of copper oxide crystals. The acquired spectra showed a unique trend of copper oxide responses. This suggests that the loaded copper oxide will exhibit unique optical signature that can be useful as an anti-tamper security feature

  • Project Report is not yet available.
  • Poster


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Alexander McKim

Bio:


2018 B.S. Clemson University, Computer Science and Economics


Project Info:


  • TITLE:
    Fast Isotopic Ratio Mass Spectrometry (FIRMS) and its effects on Counterfeit Pharmaceutical Markets

  • ABSTRACT:

    FIRMS is a software that is being developed with the goal of specifying the isotope ratios of elements in a molecule. The desired practical application of this software is to clarify what is being put into counterfeit pharmaceuticals, rather than just determine whether they are counterfeit or not. With this knowledge, we hope to be able to trace back the original chemicals that were used to a company, which would indicate what companies counterfeit businesses are buying from. Using FIRMS, the goal of this paper is to explain how the software would be a more definitive attempt at interdicting the market, and predicting how the market would react if FIRMS was successful. A major conclusion from this paper is that FIRMS can be more successful because it is going after the source chemical. Past conclusions state that it is extremely difficult to interfere with this market as all of the components that make up one of these businesses are so independent from each other. However, in reality, all components depend on the original chemical used to make the drugs. Without a line onto that chemical, it becomes more expensive and more difficult to get the product out there. Furthermore, this paper discusses the strategies of counterfeit pharmacies, and how they use technology and the internet to expand their market, and allow the business to be more organized and harder to interdict.

  • Project Report is not yet available.
  • Poster


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Greydon Shangreaux

Bio:


2019 B.S. University of Washington, Civil Engineering


Project Info:


  • TITLE:
    Scientific Analysis of Lakota Artifacts

  • ABSTRACT:

    The Heritage Center at Red Cloud Indian School entrusted students of the SPACT REU program with several artifacts potentially 250 years old. This report focuses on a wrought iron dagger fashioned to an American Black Bear jaw. (See Figure 1) Very few donated items have appropriate documentation that trace the artifacts history. The purpose of this project was to help “authenticate” the artifact using several scientific analyses. Chemical analysis using laser induced breakdown spectroscopy and x-ray fluorescence provides information about the type of steel. X-ray computed tomography builds a three-dimensional model of the construction of the knife. Direct comparison of the species used is the most elementary, and removes any doubt that the animal is not a black bear. It was found that the artifact is not a replica. Furthermore, the steel is appropriately unrefined and the construction of the knife is consistent with common tool-making practices used by Lakota people. Refined steel, albeit a new commodity, was still understood as another resource that came from the Earth, so the techniques previously used adapted quite nicely to the new resource.

    A proof of concept of security printing on Lakota art was done by participants of the 2015 SPACT REU. A covert security mark was successfully printed on a feather using ultraviolet-responsive, fluorescein-based ink. The mark was readable before and after splaying the feather. Printing a signature mark or a quick response (QR) code onto the item offers more direct validation to the consumer. We hoped to extend the list of viable substrates to quillwork and beadwork in effort to combat the reproduction and wholesale of counterfeit Native American art.

  • Project Report is not yet available.
  • Poster