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The finite temperature phase transition in four flavour QCD on an 8×12 3 lattice

We present results of a numerical study of lattice QCD with four dynamical flavours of staggered fermions, performed by using a hybrid Monte Carlo algorithm on an 8×12 3 lattice. We find a rapid change in the average value of the Polyakov loop at β c =5.25±0.025 for a quark mass ma=0.025; at this mass value, the behaviour of the chiral order parameter, 〈ΨΨ〉 does not yet allow an independent deter

A random surface representation of Wilson loops in Z(2) gauge theory

We study a random surface representation of Wilson loops in Z(2) gauge theory. The weights consist of an area factor, which dominates at strong coupling, and an excluded volume factor flavouring crumpled surfaces. We examine the latter one in some detail in three as well as four dimensions by use of Monte Carlo methods. In three dimensions, the critical behaviour of the surfaces is found to be det

The effective string and SU(2) lattice MC data

We present high statistics MC calculations of the static potential in three-dimensional SU(2) for a wide range of β values on a 243 lattice. The deviations from area law are unambiguously demonstrated by use of 2nd lattice R derivative. After a clear crossover at β=4.5 the data show signs of an effective string roughening up to β=6.5, while scaling is not strictly obeyed in this interval. Pure fer

Compact three-dimensional U(1) gauge theory reexamined

Convincing evidence of a nonvanishing string tension in the continuum limit of compact three-dimensional U(1) gauge theory is presented. It is based on Monte Carlo measurements of Wilson loops on a 323 lattice at =2.0 and 2.2. The observed string tensions at these couplings are consistent with the Polyakov theory. Also, a very clean signal of a string vibrational contribution to the potential is o

Myocardial microinfarction aF Ter coronary microembolization in swine : MR imaging characterization

Purpose: To use first-pass perfusion and delayed-enhanced (DE) magnetic resonance (MR) imaging for the detection of the early effects of coronary microembolization on myocardial perfusion and viability. Materials and Methods: Approval was obtained from the institutional committee on animal research. A hybrid x-ray and MR imaging system was used to guide the endovascular catheter and quantify the l

Measurement of Tc in the scaling region of (2+1)-dimensional SU(2) lattice gauge theory

The deconfinement temperature Tc of (2+1)-dimensional SU(2) gauge theory is measured on lattice sizes varying from 2 × 202 to 6 × 602 and with β in the rate 3-9. Approximative scaling is found for β > 6.5 and Tc/√σ = 0.94 ± 0.03 is obtained. This value is in excellent agreement with (3/π) 1 2, as predicted from the breakdown of SU(2) confinement in terms of an effective scalar string theory.

Numerical evidence for a mass gap in three-dimensional SU(2)

Numerical evidence for a nonvanishing 0++ glueball mass in three-dimensional SU(2) is presented. By using a long-distance correlation Monte Carlo method we obtain m0++ = (4.7±1.2)√σ in the β-range 4.0-6.5. The measurements are consistent with 1/β-scaling. The relevance of this result for SU(2) in four dimensions at finite temperature is briefly discussed.

Experimental and Numerical Investigations of Heat Transfer related to Gas Turbine Applications

Gas turbines are broadly used in aerospace and marine propulsion and power production etc.Investigation of heat transfer in gas turbines is a long-lasting and still an active subject ofresearch due to its tremendous importance. Thermal efficiency, durability and fatigue lifetimeof a gas turbine greatly rely on the heat transfer characteristics of gas turbine components.According to the first law o

Assessing cereal grain quality with a fully automated instrument using artificial neural network processing of digitized color video images

A fully integrated instrument for cereal grain quality assessment is presented. Color video images of grains fed onto a belt are digitized. These images are then segmented into kernel entities, which are subject to the analysis. The number of degrees of freedom for each such object is decreased to a suitable level for Artificial Neural Network (ANN) processing. Feed- forward ANN's with one hidden

Delta 2.0 - A program for finding dependencies in tables of data

A package written in C for identifying variable dependencies in tables of data is presented. The key ingredient is the δ-test, which establishes dependency structures by exploiting the properties of continuous functions using conditional probabilities formed out of the data. The method estimates most relevant variables, embedding dimensions and noise levels. The program, which is self-contained, a

Solving optimization problems with mean field methods

A brief review is given for the use of feed-back artificial neural networks (ANN) to obtain good approximate solutions to combinatorial optimization problems. The key element is the mean field approximation (MFT), which differs from conventional methods and "feels" its ways towards good solutions rather than fully or partly exploring different possible solutions. The methodology, which is illustra

A 3-dimensional Z 3 symmetric model : Correlation lengths at a first order phase transition

We present a high statistics Monte Carlo investigation of a 3-dimensional Z 3 symmetric model, which is related to SU(3) pure gauge theory at finite temperature. From the finite size scaling behaviour of bulk properties and the existence of metastable states, we conclude that this model exhibits a first-order phase transition. We have also performed detailed correlation length measurements in a c

Mass reconstruction with a neural network

A feed-forward neural network method is developed for reconstructing the invariant mass of hadronic jets appearing in a calorimeter. The approach is illustrated in W→qq, where W-bosons are produced in pp reactions at SPS collider energies. The neural network method yields results that are superior to conventional methods. This neural network application differs from the classification ones in the

Particle tracking by deformable templates

The authors describe an approach to particle tracking based on deformable templates. Hough transforms are used to give initial conditions for the templates which then converge using a deterministic annealing algorithm. This template approach is closely related to the elastic net algorithm. The authors demonstrate successful results on both simulated and real data. The authors also show how the Hou

Optoelectronic implementation of multilayer neural networks in a single photorefractive crystal

We present a novel, versatile optoelectronic neural network architecture for implementing supervised learning algorithms in photorefractive materials. The system is based on spatial multiplexing rather than the more commonly used angular multiplexing of the interconnect gratings. This simple, single-crystal architecture implements a variety of multilayer supervised learning algorithms including me

Test-retest repeatability of human speech biomarkers from static and real-time dynamic magnetic resonance imaging

Static anatomical and real-time dynamic magnetic resonance imaging (RT-MRI) of the upper airway is a valuable method for studying speech production in research and clinical settings. The test-retest repeatability of quantitative imaging biomarkers is an important parameter, since it limits the effect sizes and intragroup differences that can be studied. Therefore, this study aims to present a fram