Hierarchical mixture models for assessing fingerprint individuality

The study of fingerprint individuality aims to determine to what extent a fingerprint uniquely identifies an individual. Recent court cases have highlighted the need for measures of fingerprint individuality when a person is identified based on fingerprint evidence. The main challenge in studies of fingerprint individuality is to adequately capture the variability of fingerprint features in a population. In this paper hierarchical mixture models are introduced to infer the extent of individualization. Hierarchical mixtures utilize complementary aspects of mixtures at different levels of the hierarchy. At the first (top) level, a mixture is used to represent homogeneous groups of fingerprints in the population, whereas at the second level, nested mixtures are used as flexible representations of distributions of features from each fingerprint. Inference for hierarchical mixtures is more challenging since the number of unknown mixture components arise in both the first and second levels of the hierarchy. A Bayesian approach based on reversible jump Markov chain Monte Carlo methodology is developed for the inference of all unknown parameters of hierarchical mixtures. The methodology is illustrated on fingerprint images from the NIST database and is used to make inference on fingerprint individuality estimates from this population.Comment: Published in at http://dx.doi.org/10.1214/09-AOAS266 the Annals of Applied Statistics (http://www.imstat.org/aoas/) by the Institute of Mathematical Statistics (http://www.imstat.org

Inference for Differential Equation Models using Relaxation via Dynamical Systems

Statistical regression models whose mean functions are represented by ordinary differential equations (ODEs) can be used to describe phenomenons dynamical in nature, which are abundant in areas such as biology, climatology and genetics. The estimation of parameters of ODE based models is essential for understanding its dynamics, but the lack of an analytical solution of the ODE makes the parameter estimation challenging. The aim of this paper is to propose a general and fast framework of statistical inference for ODE based models by relaxation of the underlying ODE system. Relaxation is achieved by a properly chosen numerical procedure, such as the Runge-Kutta, and by introducing additive Gaussian noises with small variances. Consequently, filtering methods can be applied to obtain the posterior distribution of the parameters in the Bayesian framework. The main advantage of the proposed method is computation speed. In a simulation study, the proposed method was at least 14 times faster than the other methods. Theoretical results which guarantee the convergence of the posterior of the approximated dynamical system to the posterior of true model are presented. Explicit expressions are given that relate the order and the mesh size of the Runge-Kutta procedure to the rate of convergence of the approximated posterior as a function of sample size

Squeezing in Multivariate Spin Systems

In contrast to the canonically conjugate variates $q$,$p$ representing the position and momentum of a particle in the phase space distributions, the three Cartesian components, $J_{x}$,$J_{y}$, $J_{z}$ of a spin-$j$ system constitute the mutually non-commuting variates in the quasi-probabilistic spin distributions. It can be shown that a univariate spin distribution is never squeezed and one needs to look into either bivariate or trivariate distributions for signatures of squeezing. Several such distributions result if one considers different characteristic functions or moments based on various correspondence rules. As an example, discrete probability distribution for an arbitrary spin-1 assembly is constructed using Wigner-Weyl and Margenau-Hill correspondence rules. It is also shown that a trivariate spin-1 assembly resulting from the exposure of nucleus with non-zero quadrupole moment to combined electric quadrupole field and dipole magnetic field exhibits squeezing in cerain cases.Comment: 13 pages, 1 Table, Presented at ICSSUR-05, Franc

Testing the ΔS=ΔQ\Delta S=\Delta Q Rule with Exclusive Semi-Leptonic Kaon Decays

We consider the possibility of violations of the selection rule $\Delta S=\Delta Q$ at an appreciable level in {\it exclusive} semi-leptonic decays of Kaons. At $\Phi$-Factories, intense Kaon beams will be available and will probe among others, the semi-leptonic decays $K_{l4}$ and $K_{l3\gamma}$ in addition to $K_{l3}$ and could provide novel testing grounds for the $\Delta S=\Delta Q$ rule. In particular, the branching ratio of $K_{l3\gamma}$ is non-negligible and could be used to probe new phenomena associated with the violation of this selection rule. Furthermore, we modify certain di-lepton event rate ratios and asymmetries and time asymmetries that have been constructed by Dass and Sarma for di-lepton events from Beon decays to test the $\Delta B=\Delta Q$ at the $\Upsilon (4S)$, to the Kaon system at the $\phi(1020)$. We find that the large width of the $K_S$ relative to that of $K_L$ plays an important role in enhancing some of the time asymmetries.Comment: 10 pages, Plain Latex, To be run twice

Expedient airfield runway repair using folded fiberglass mat

For expedient airfield runway repair, the US Air Force has developed a folded fiberglass mat to cover craters repaired with a well-compacted granular base material. The objective of this study was to evaluate the adequacy of using polymer plugs to anchor the mat to a repaired asphalt pavement for heavy aircraft operations. The effort consisted of materials testing, field experiments and analytical modeling. An 89,800-kg (198,000-pound) load cart having the footprint of a single C-5 main gear was pulled on a mat with wheels locked to simulate full braking forces. Anchor bushings were instrumented to measure anchor loads. A simplified numerical model was developed for anchor load analysis which has been validated against the load cart test data. The anchor system sustained the braking forces from all the load cart tests without failure. The polymer plug anchors have adequate vertical pull-out capacity to resist the uplifting force from the “bow wave” formation of the mat. The polymer plug anchors also have adequate resistance to fatigue loads

Expedient airfield runway repair using folded fiberglass mat

For expedient airfield runway repair, the US Air Force has developed a folded fiberglass mat to cover craters repaired with a well-compacted granular base material. The objective of this study was to evaluate the adequacy of using polymer plugs to anchor the mat to a repaired asphalt pavement for heavy aircraft operations. The effort consisted of materials testing, field experiments and analytical modeling. An 89,800-kg (198,000-pound) load cart having the footprint of a single C-5 main gear was pulled on a mat with wheels locked to simulate full braking forces. Anchor bushings were instrumented to measure anchor loads. A simplified numerical model was developed for anchor load analysis which has been validated against the load cart test data. The anchor system sustained the braking forces from all the load cart tests without failure. The polymer plug anchors have adequate vertical pull-out capacity to resist the uplifting force from the “bow wave” formation of the mat. The polymer plug anchors also have adequate resistance to fatigue loads

Effect of gibberellin on seeded Vitis vinifera with special reference to induction of seedlessness

Application of GA (25-50 ppm) to Ana:b-e-Shahi at prebloom stage decreased the bunch weight and berry number but weight of the berries was increased and up to 29.6% seedless berries were induced. GA sprays (25-50 ppm) at 2-3 days after full lbloom increased the bunch and berry weights but few seedless berries were induced.GA application (50-150 ppm) to Bhokri grape at 10-11 days before full bloom formed more than 90% seedless berries but bunch weights and berry number were reduced. WitJh an additional second spray at 7- 8 days after full bloom, berry size was impmved but bunch weights were still reduced. At 4-5 days before full bloom application of GA, up to 41.4 % seedless berries were induced but bunch and berry weights were a,gain reduced. With another spray at postbloom stage bunch and berry weights were brought to the level of control.   In Gros Colman (Pusa) grape, GA application (50-100 ppm) at 5-6 days before full bloom and 2-3 days after full bloom also formed seedless berries but the bunch and berry weights were reduced. IFruit set was also improvP.d at boVh stages of spray. Prebloom GA application (50-150 ppm) to Alamwick grape, produced seedless berries up to 38.29% but ,bunch and berry weights were appreciably decreased. No effect on berry number was noticed.Application of GA (25-75 ppm) at prebloom + posbbloom and postbloom alone decreased the bunch and berry weights and berry number markedly of Bharat Early and Black Hamburg varieties. Toxic effects like shot berry formation and cracking of rachis were noticed. No seedless berries were observed. however, more berries with 1 or 2 seeds were formed at the expense of berries with 3 or 4 seeds. Even GA application at Jow concentrations to these varieties (5-25 ppm) reduced bunch weights and berry number.The differential response of these seeded varieties of Vitis vinifera is attributed to different amounts of growth factors and inhibitors present in them

Mechanical Properties of Vitrified Soils

Recent advances in plasma arc technology have found many civil engineering applications, including in-situ soil vitrification (ISV). The ISV process transforms soils into homogeneous glass-like materials, which possess high compressive and tensile strengths (typically about 10 times those of unreinforced concrete), high leaching resistance, and are unaffected by wet-dry or freeze-thaw cycles. These vitrified earthen materials usually weigh about 2300 to 2500 kg per cubic meter. Potential ISV applications include slope stabilization, groundwater removal, subgrade stabilization, and simulated construction materials. A 100-kW non-transferred plasma arc torch developed by the Plasma Energy Corporation was used for soil vitrification experiments with operating temperatures at about 4000°C. The soils tested include Piedmont silty sand, kaolin clay, and Tyndall beach sand. 5.1-cm cubes and 5.1-cm diameter cylinders were cut from the vitrified soil samples and subjected to compression tests, split-cylinder tension tests, and split-Hopkinson bar impact tests

Differential response of some seeded grape cultivars of Vitis vinifera to gibberellin application

Several seeded cultivar,s of Vitis vinifera varying in seed content and berry size were tested to see their response to GA application. Oultivars with high seed index number and low seed content like Bhokri, Anab-e-Shahi, Gros Colman (Pusa) and Alamwick did not show any toxic effects due to GA application but responded by producing seedless berries and increasing berry weight with prebloom and postbloom application respectively. Alamwick alone, with high seed index number did not respond to GA by increasing the berry weight but it responded by forming seedless berries. Oultivars like Bharat Early, Black Hamburg and Black Muscat with high seed content per berry and low seed index number did not respond to GA by producing seedless berries and increasing berry weight. This differential response of cultivars to exogenous GA is discussed on the basis of physiological differences in the two groups of cultivars