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Vaporization of synthetic fuels. Final report.

Description: The problem of transient droplet vaporization in a hot convective environment is examined. The main objective of the present study is to develop an algorithm for the droplet vaporization which is simple enough to be feasibly incorporated into a complete spray combustion analysis and yet will also account for the important physics such as liquid-phase internal circulation, unsteady droplet heating and axisymmetric gas-phase convection. A simplified liquid-phase model has been obtained based on t… more
Date: January 1, 1983
Creator: Sirignano, W. A.; Yao, S. C.; Tong, A. Y. & Talley, D.
Partner: UNT Libraries Government Documents Department
open access

Around the Fibonacci Numeration System

Description: Let 1, 2, 3, 5, 8, … denote the Fibonacci sequence beginning with 1 and 2, and then setting each subsequent number to the sum of the two previous ones. Every positive integer n can be expressed as a sum of distinct Fibonacci numbers in one or more ways. Setting R(n) to be the number of ways n can be written as a sum of distinct Fibonacci numbers, we exhibit certain regularity properties of R(n), one of which is connected to the Euler φ-function. In addition, using a theorem of Fine and Wilf, we… more
Date: May 2007
Creator: Edson, Marcia Ruth
Partner: UNT Libraries
open access

Efficient Parallel Algorithms and Data Structures Related to Trees

Description: The main contribution of this dissertation proposes a new paradigm, called the parentheses matching paradigm. It claims that this paradigm is well suited for designing efficient parallel algorithms for a broad class of nonnumeric problems. To demonstrate its applicability, we present three cost-optimal parallel algorithms for breadth-first traversal of general trees, sorting a special class of integers, and coloring an interval graph with the minimum number of colors.
Date: December 1991
Creator: Chen, Calvin Ching-Yuen
Partner: UNT Libraries
open access

Performance Study of Concurrent Search Trees and Hash Algorithms on Multiprocessors Systems

Description: This study examines the performance of concurrent algorithms for B-trees and linear hashing. B-trees are widely used as an access method for large, single key, database files, stored in lexicographic order on secondary storage devices. Linear hashing is a fast and reliable hash algorithm, suitable for accessing records stored unordered in buckets. This dissertation presents performance results on implementations of concurrent Bunk-tree and linear hashing algorithms, using lock-based, partitione… more
Date: May 1996
Creator: Demuynck, Marie-Anne
Partner: UNT Libraries
open access

Type Ia supernova rate studies from the SDSS-II Supernova Study

Description: The author presents new measurements of the type Ia SN rate from the SDSS-II Supernova Survey. The SDSS-II Supernova Survey was carried out during the Fall months (Sept.-Nov.) of 2005-2007 and discovered {approx} 500 spectroscopically confirmed SNe Ia with densely sampled (once every {approx} 4 days), multi-color light curves. Additionally, the SDSS-II Supernova Survey has discovered several hundred SNe Ia candidates with well-measured light curves, but without spectroscopic confirmation of typ… more
Date: August 1, 2008
Creator: Dilday, Benjamin
Partner: UNT Libraries Government Documents Department
open access

Grid Development and a Study of B-flavour tagging at D�

Description: Run IIa of the D0 experiment at the Tevatron took place between Spring 2002 and Spring 2006, collecting approximately 1.2 fb{sup -1} of data. A fundamental principal of the D0 computing model is the utilization of globally distributed computing resources as part of a grid. In particular use is made of the 'SAMGrid'. The first part of this thesis describes the work undertaken at Imperial College on several D0 distributed computing projects. These included the deployment and development of parts … more
Date: September 1, 2006
Creator: Lewis, Philip William
Partner: UNT Libraries Government Documents Department
open access

Limit on the muon neutrino magnetic moment and a measurement of the CCPIP to CCQE cross section ratio

Description: A search for the muon neutrino magnetic moment was conducted using the Mini-BooNE low energy neutrino data. The analysis was performed by analyzing the elastic scattering interactions of muon neutrinos on electrons. The analysis looked for an excess of elastic scattering events above the Standard Model prediction from which a limit on the neutrino magnetic could be set. In this thesis, we report an excess of 15.3 {+-} 6.6(stat){+-}4.1(syst) {nu}{sub {mu}e} events above the expected background. … more
Date: July 1, 2008
Creator: Ouedraogo, Serge Aristide & U., /Louisiana State
Partner: UNT Libraries Government Documents Department
open access

Seismic velocity estimation from time migration

Description: This is concerned with imaging and wave propagation in nonhomogeneous media, and includes a collection of computational techniques, such as level set methods with material transport, Dijkstra-like Hamilton-Jacobi solvers for first arrival Eikonal equations and techniques for data smoothing. The theoretical components include aspects of seismic ray theory, and the results rely on careful comparison with experiment and incorporation as input into large production-style geophysical processing code… more
Date: May 31, 2007
Creator: Cameron, Maria Kourkina
Partner: UNT Libraries Government Documents Department
open access

Development and Integration of Hardware and Software for Active-Sensors in Structural Monitoring

Description: Structural Health Monitoring (SHM) promises to deliver great benefits to many industries. Primarily among them is a potential for large cost savings in maintenance of complex structures such as aircraft and civil infrastructure. However, several large obstacles remain before widespread use on structures can be accomplished. The development of three components would address many of these obstacles: a robust sensor validation procedure, a low-cost active-sensing hardware and an integrated softwar… more
Date: October 15, 2007
Creator: Overly, Timothy G.S.
Partner: UNT Libraries Government Documents Department
open access

Quantum Dynamical Behaviour in Complex Systems - A Semiclassical Approach

Description: One of the biggest challenges in Chemical Dynamics is describing the behavior of complex systems accurately. Classical MD simulations have evolved to a point where calculations involving thousands of atoms are routinely carried out. Capturing coherence, tunneling and other such quantum effects for these systems, however, has proven considerably harder. Semiclassical methods such as the Initial Value Representation (SC-IVR) provide a practical way to include quantum effects while still utilizing… more
Date: May 22, 2008
Creator: Gliebe, Cheryn E & Ananth, Nandini
Partner: UNT Libraries Government Documents Department
open access

Optimization of accelerator parameters using normal form methods on high-order transfer maps

Description: Methods of analysis of the dynamics of ensembles of charged particles in collider rings are developed. The following problems are posed and solved using normal form transformations and other methods of perturbative nonlinear dynamics: (1) Optimization of the Tevatron dynamics: (a) Skew quadrupole correction of the dynamics of particles in the Tevatron in the presence of the systematic skew quadrupole errors in dipoles; (b) Calculation of the nonlinear tune shift with amplitude based on the resu… more
Date: May 1, 2007
Creator: Snopok, Pavel
Partner: UNT Libraries Government Documents Department
open access

Search for Higgs Boson Production in Association with a W Boson in 1.96-TeV Proton - Antiproton Collisions

Description: We have searched for the Standard Model Higgs boson production in association with a W{sup {+-}} boson. This search is based on the data collected between February 2002 and May 2007, corresponding to an integrated luminosity of 1.9 fb{sup -1} collected by the Collider Detector at Fermilab (CDF) at the Tevatron which is a p{bar p} collider at a center of mass energy 1.96 TeV. W+Higgs channel is one of the most promising channels for the Higgs search at Tevatron in the low Higgs mass region (m{su… more
Date: February 1, 2008
Creator: Masubuchi, Tatusya
Partner: UNT Libraries Government Documents Department
open access

Calibration of new flavor tagging algorithms using Bs oscillations

Description: Over the past decades the current theoretical description, the Standard Model of elementary particle physics, was solidified by many measurements as the basic theory describing fundamental particles and their interactions. It is extremely successful in explaining the high-precision data collected by experiments so far. The Standard Model includes several intrinsic parameters which have to be measured in experiments. Independent analyses of different physical processes can constrain those parame… more
Date: July 1, 2007
Creator: Mack, Philipp
Partner: UNT Libraries Government Documents Department
open access

Measurement of Inclusive Jet Cross Sections in Z/gamma*(->e+e-) + jets Production in ppbar Collisions at s**(1/2) = 1.96 TeV with the CDF Detector

Description: This Ph.D. thesis presents the measurement of inclusive jet cross sections in Z/{gamma}* {yields} e{sup +}e{sup -} events using 1.7 fb{sup -1} of data collected by the upgraded CDF detector during the Run II of the Tevatron. The Midpoint cone algorithm is used to search for jets in the events after identifying the presence of a Z/{gamma}* boson through the reconstruction of its decay products. The measurements are compared to next-to-LO (NLO) pQCD predictions for events with one and two jets in… more
Date: April 1, 2008
Creator: Salto Bauza, Oriol
Partner: UNT Libraries Government Documents Department
open access

Study of t anti-t production in tau jets channel at CDFII using neural networks

Description: CDF (Collider Detector at Fermilab) is a particle detector located at Fermi National Laboratories, near Chicago. it allows to study decay products of p{bar p} collisions at center-of-mass energy of 1.96 TeV. During its first period of data taking (RunI), CDF observed for the first time the top quark (1995). The current period of data taking (RunII) is devoted to precise measurements of top properties and to search for new physics. This thesis work is about the top decay channel named {tau} + je… more
Date: December 1, 2005
Creator: Amerio, Silvia
Partner: UNT Libraries Government Documents Department
open access

Evolution, Interaction, and Intrinsic Properties of Dislocations in Intermetallics: Anisotropic 3D Dislocation Dynamics Approach

Description: The generation, motion, and interaction of dislocations play key roles during the plastic deformation process of crystalline solids. 3D Dislocation Dynamics has been employed as a mesoscale simulation algorithm to investigate the collective and cooperative behavior of dislocations. Most current research on 3D Dislocation Dynamics is based on the solutions available in the framework of classical isotropic elasticity. However, due to some degree of elastic anisotropy in almost all crystalline sol… more
Date: August 18, 2008
Creator: Chen, Qian
Partner: UNT Libraries Government Documents Department
open access

Measurement of the Top Quark Mass using Dilepton Events and a Neutrino Weighting Algorithm with the D0 Experiment at the Tevatron (Run II)

Description: Elementary particle physics raises questions that are several thousand years old. What are the fundamental components of matter and how do they interact? These questions are linked to the question of what happened in the very first moments after the creation of the universe. Modern physics systematically tests nature to find answers to these and other fundamental questions. Precise theories are developed that describe various phenomena and at the same time are reduced to a few basic principals … more
Date: January 1, 2007
Creator: Meyer, Joerg
Partner: UNT Libraries Government Documents Department
open access

Top quark pair production cross section in the lepton+jets channel using b-tagging at D0

Description: The top quark pair production cross section measurement in the lepton+jets channel with b-tagging algorithm is described. About 900 pb{sup -1} data collected by the D0 detector at the Fermilab Tevatron are used for this analysis. In this thesis, event selection, background estimation, and cross section calculation are discussed in detail. In addition, calibration of the Luminosity Monitor readout electronics and a new b-tagging algorithm, the SLTNN tagger, are also discussed in this thesis.
Date: May 1, 2008
Creator: Yoo, H.D. & U., /Brown
Partner: UNT Libraries Government Documents Department
open access

Linear Unification

Description: Efficient unification is considered within the context of logic programming. Unification is explained in terms of equivalence classes made up of terms, where there is a constraint that no equivalence class may contain more than one function term. It is demonstrated that several well-known "efficient" but nonlinear unification algorithms continually maintain the said constraint as a consequence of their choice of data structure for representing equivalence classes. The linearity of the Paterson-… more
Date: December 1989
Creator: Wilbanks, John W. (John Winston)
Partner: UNT Libraries
open access

A Tool for Measuring the Size, Structure and Complexity of Software

Description: The problem addressed by this thesis is the need for a software measurement tool that enforces a uniform measurement algorithm on several programming languages. The introductory chapter discusses the concern for software measurement and provides background for the specific models and metrics that are studied. A multilingual software measurement tool is then introduced, that analyzes programs written in Ada, C, Pascal, or PL/I, and quantifies over thirty different program attributes. Metrics com… more
Date: May 1984
Creator: Versaw, Larry
Partner: UNT Libraries
open access

Computer Graphics Primitives and the Scan-Line Algorithm

Description: This paper presents the scan-line algorithm which has been implemented on the Lisp Machine. The scan-line algorithm resides beneath a library of primitive software routines which draw more fundamental objects: lines, triangles and rectangles. This routine, implemented in microcode, applies the A(BC)*D approach to word boundary alignments in order to create an extremely fast, efficient, and general purpose drawing primitive. The scan-line algorithm improves on previous methodologies by limiting … more
Date: December 1988
Creator: Myjak, Michael D. (Michael David)
Partner: UNT Libraries
open access

An Efficient Hybrid Heuristic and Probabilistic Model for the Gate Matrix Layout Problem in VLSI Design

Description: In this thesis, the gate matrix layout problem in VLSI design is considered where the goal is to minimize the number of tracks required to layout a given circuit and a taxonomy of approaches to its solution is presented. An efficient hybrid heuristic is also proposed for this combinatorial optimization problem, which is based on the combination of probabilistic hill-climbing technique and greedy method. This heuristic is tested experimentally with respect to four existing algorithms. As test ca… more
Date: August 1993
Creator: Bagchi, Tanuj
Partner: UNT Libraries
open access

Fundamental Issues in Support Vector Machines

Description: This dissertation considers certain issues in support vector machines (SVMs), including a description of their construction, aspects of certain exponential kernels used in some SVMs, and a presentation of an algorithm that computes the necessary elements of their operation with proof of convergence. In its first section, this dissertation provides a reasonably complete description of SVMs and their theoretical basis, along with a few motivating examples and counterexamples. This section may be … more
Date: May 2014
Creator: McWhorter, Samuel P.
Partner: UNT Libraries
open access

Strangeonium spectroscopy at 11 GeV/c and Cherenkov Ring Imaging at the SLD

Description: This thesis is divided into two sections, which describe portions of the data acquisition system and online software for the Cherenkov Ring Imaging Detector (CRID) for the SLD, and analyses of several low cross section strangeonium channels in data from the LASS spectrometer. The CRID section includes a description of the data acquisition system, determination of the preamplifier gain, and development of an online pulse finding algorithm based on deconvolution. Deconvolution uses knowledge of t… more
Date: July 1990
Creator: Bienz, Timothy Lawrence
Partner: UNT Libraries Government Documents Department
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