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Articles 2701 - 2730 of 8620
Full-Text Articles in Physical Sciences and Mathematics
On The Sampling Of Web Images For Learning Visual Concept Classifiers, Shiai Zhu, Gang Wang, Chong-Wah Ngo, Yu-Gang Jiang
On The Sampling Of Web Images For Learning Visual Concept Classifiers, Shiai Zhu, Gang Wang, Chong-Wah Ngo, Yu-Gang Jiang
Research Collection School Of Computing and Information Systems
Visual concept learning often requires a large set of training images. In practice, nevertheless, acquiring noise-free training labels with sufficient positive examples is always expensive. A plausible solution for training data collection is by sampling the largely available user-tagged images from social media websites. With the general belief that the probability of correct tagging is higher than that of incorrect tagging, such a solution often sounds feasible, though is not without challenges. First, user-tags can be subjective and, to certain extent, are ambiguous. For instance, an image tagged with “whales” may be simply a picture about ocean museum. Learning concept …
Hybrid Time-Frequency Domain Analysis For Inverter-Fed Induction Motor Fault Detection, T. W. Chua, W. W. Tan, Zhaoxia Wang, C. S. Chang
Hybrid Time-Frequency Domain Analysis For Inverter-Fed Induction Motor Fault Detection, T. W. Chua, W. W. Tan, Zhaoxia Wang, C. S. Chang
Research Collection School Of Computing and Information Systems
The detection of faults in an induction motor is important as a part of preventive maintenance. Stator current is one of the most popular signals used for utility-supplied induction motor fault detection as a current sensor can be installed nonintrusively. In variable speeds operation, the use of an inverter to drive the induction motor introduces noise into the stator current so stator current based fault detection techniques become less reliable. This paper presents a hybrid algorithm, which combines time and frequency domain analysis, for broken rotor bar and bearing fault detection. Cluster information obtained by using Independent Component Analysis (ICA) …
A Heuristic Algorithm For Trust-Oriented Service Provider Selection In Complex Social Networks, Guanfeng Liu, Yan Wang, Mehmet A. Orgun, Ee Peng Lim
A Heuristic Algorithm For Trust-Oriented Service Provider Selection In Complex Social Networks, Guanfeng Liu, Yan Wang, Mehmet A. Orgun, Ee Peng Lim
Research Collection School Of Computing and Information Systems
In a service-oriented online social network consisting of service providers and consumers, a service consumer can search trustworthy service providers via the social network. This requires the evaluation of the trustworthiness of a service provider along a certain social trust path from the service consumer to the service provider. However, there are usually many social trust paths between participants in social networks. Thus, a challenging problem is which social trust path is the optimal one that can yield the most trustworthy evaluation result. In this paper, we first present a novel complex social network structure and a new concept, Quality …
Effective Heuristic Methods For Finding Non-Optimal Solutions Of Interest In Constrained Optimization Models, Steven O. Kimbrough, Ann Kuo, Hoong Chuin Lau
Effective Heuristic Methods For Finding Non-Optimal Solutions Of Interest In Constrained Optimization Models, Steven O. Kimbrough, Ann Kuo, Hoong Chuin Lau
Research Collection School Of Computing and Information Systems
This paper introduces the SoI problem, that of finding nonoptimal solutions of interest for constrained optimization models. SoI problems subsume finding FoIs (feasible solutions of interest), and IoIs (infeasible solutions of interest). In all cases, the interest addressed is post-solution analysis in one form or another. Post-solution analysis of a constrained optimization model occurs after the model has been solved and a good or optimal solution for it has been found. At this point, sensitivity analysis and other questions of import for decision making (discussed in the paper) come into play and for this purpose the SoIs can be of …
Faceted Topic Retrieval Of News Video Using Joint Topic Modeling Of Visual Features And Speech Transcripts, Kong-Wah Wan, Ah-Hwee Tan, Joo-Hwee Lim, Liang-Tien Chia
Faceted Topic Retrieval Of News Video Using Joint Topic Modeling Of Visual Features And Speech Transcripts, Kong-Wah Wan, Ah-Hwee Tan, Joo-Hwee Lim, Liang-Tien Chia
Research Collection School Of Computing and Information Systems
Because of the inherent ambiguity in user queries, an important task of modern retrieval systems is faceted topic retrieval (FTR), which relates to the goal of returning diverse or novel information elucidating the wide range of topics or facets of the query need. We introduce a generative model for hypothesizing facets in the (news) video domain by combining the complementary information in the visual keyframes and the speech transcripts. We evaluate the efficacy of our multimodal model on the standard TRECVID-2005 video corpus annotated with facets. We find that: (1) the joint modeling of the visual and text (speech transcripts) …
Duffing-Van Der Pol Type Oscillator, Guangyue Gao
Duffing-Van Der Pol Type Oscillator, Guangyue Gao
Theses and Dissertations - UTB/UTPA
The nonlinear Duffing-van der Pol oscillator system is studied by means of the Lie symmetry reduction method and the Preller-Singer method. With the particular case of coefficients, this system has physical relevance as a simple model in certain flow-induced structural vibration problems. Under certain parametric conditions, we are concerned with the first integrals of the Duffing-van der Pol oscillator system. After making a series of variable transformations, we apply the Preller-Singer method and the Lie symmetry reduction method to obtain the first integrals of the simplified equations without complicated calculations.
Soliton Solutions To Integrable Equations, Haiqi Wang
Soliton Solutions To Integrable Equations, Haiqi Wang
Theses and Dissertations - UTB/UTPA
In recent years, integrable systems and soliton theory play an important role in the study of nonlinear water wave equations. In this thesis, we will focus on the procedure of how to get soliton solutions for integrable equations. The fundamental idea is to use the traveling wave setting to convert a partial differential equation to an ordinary differential equation and to solve ordinary differential equations yields soliton solutions for the integrable equations under certain boundary conditions at both negative and positive infinities. In our work, we will consider five integrable equations and present their solitons solutions, one of which will …
Modeling Instabilities Of Electrically Driven Jets With Finite Conductivity Under Constant Or Variable Applied Field, Saulo I. Orizaga
Modeling Instabilities Of Electrically Driven Jets With Finite Conductivity Under Constant Or Variable Applied Field, Saulo I. Orizaga
Theses and Dissertations - UTB/UTPA
We investigate the problem of spatial (S), combined spatial and temporal (CST), and non-linear temporal instability (NLT) of electrically driven viscous jets with finite electrical conductivity and in the presence of either a constant or a variable applied electric field. A mathematical model, which is developed and used for the spatially growing disturbances in electrically driven jet flows, leads to a lengthy equation for the unknown growth rate and frequency of the disturbances. This equation is solved numerically using Newton‟s Method. For neutral temporal stability boundary, we find, in particular, two new spatial modes of instability under certain conditions. One …
Algorithmic Temperature 1 Self-Assembly, Yunhui Fu
Algorithmic Temperature 1 Self-Assembly, Yunhui Fu
Theses and Dissertations - UTB/UTPA
We investigate the power of the Wang tile self-assembly model at temperature 1, a threshold value that permits attachment between any two tiles that share even a single bond. When restricted to deterministic assembly in the plane, no temperature 1 assembly system has been shown to build a shape with a tile complexity smaller than the diameter of the shape. Our work shows a sharp contrast in achievable tile complexity at temperature 1 if either growth into the third dimension or a small probability of error are permitted. Motivated by applications in nanotechnology and molecular computing, and the plausibility of …
New Algorithms For Protein Structure Comparison And Protein Structure Prediction, Zaixin Lu
New Algorithms For Protein Structure Comparison And Protein Structure Prediction, Zaixin Lu
Theses and Dissertations - UTB/UTPA
Proteins show a great variety of 3D conformations, which can be used to infer their evolutionary relationship and to classify them into more general groups; therefore algorithms of protein structure alignment, protein similarity search and protein structure prediction are very helpful for protein biologists. We developed new algorithms for the problems in this field. The algorithms are tested with structures from the Protein Data Bank (PDB) and SCOP, a Structure Classification of Protein Database. The experimental results show that our tools are more efficient than some well known systems for finding similar protein structures and predicting protein structures.
Experimental Investigation Of A Non-Thermal Atmospheric Pressure Plasma Jet, Asma Begum
Experimental Investigation Of A Non-Thermal Atmospheric Pressure Plasma Jet, Asma Begum
Electrical & Computer Engineering Theses & Dissertations
The main objective of this dissertation is to understand the formation of the plasma jet from the plasma pencil, and the propagation of the plasma jet in the ambient atmosphere where the effect of the external electric field is almost zero. Before investigating the formation and propagation phenomenon of the plasma jet, common physical properties of plasma jets are determined by using the imaging technique and optical emission spectroscopy. The first goal of this dissertation is to establish the laminar helium gas flow channel through a plasma pencil.
The formation position, formation time, and the criterion of the plasma jet …
A Study Of Relationships Between Family Members Using Familial Correlations, Corinne Wilson
A Study Of Relationships Between Family Members Using Familial Correlations, Corinne Wilson
Mathematics & Statistics Theses & Dissertations
Familial correlations measure the resemblance between family members and are used in many fields of study including epidemiology, genetics, heredity, and psychology. Here, an analysis of familial correlations where male and female children of the same family can have different correlations in the unequal family size case is presented. First, three likelihood based tests, namely the likelihood ratio test, Rao score test, and Wald test, and two more asymptotic tests which use Srivastava's estimator of the intraclass correlation coefficient are considered to test the null hypothesis of equality of the intraclass correlation coefficients when families have unequal numbers of children. …
Rock Magnetic And Remanence Properties Of Both Synthetic Martian Basaltic Intrusions And Dropstones Along The East Antarctic Margin, To Aid In The Understanding Of The Carriers Of Crustal Magnetic Anomalies, David Michael Cuomo Jr.
Rock Magnetic And Remanence Properties Of Both Synthetic Martian Basaltic Intrusions And Dropstones Along The East Antarctic Margin, To Aid In The Understanding Of The Carriers Of Crustal Magnetic Anomalies, David Michael Cuomo Jr.
Theses, Dissertations and Culminating Projects
This thesis examines potential carriers of magnetic anomalies found in remote areas where direct sampling is impossible. The areas examined are the southern hemisphere of Mars and the East Antarctic Margin. We examine the rock magnetic and remanence properties of synthetic Mars basalts and Antarctic dropstones, to predict the type and intensity of anomaly they would produce.
The anomalies measured within the Martian crust are entirely remanent magnetization and are remarkably orders of magnitude stronger than the strongest terrestrial anomaly. Two basalt compositions denoted M-type and T-type, deemed relevant to the crust of Mars, were synthesized to examine contrasts in …
Simultaneous Higher Harmonic Detection And Extraction Of Information From Oxygen Spectra, Karan Dineshchandra Mohan
Simultaneous Higher Harmonic Detection And Extraction Of Information From Oxygen Spectra, Karan Dineshchandra Mohan
Electrical & Computer Engineering Theses & Dissertations
Wavelength Modulation Spectroscopy (WMS) is a highly sensitive technique that utilizes synchronous detection at the N-th harmonics of a modulating frequency, by modulating the laser beam used to probe a gaseous species. The advantage of this technique lies in the greater effective signal-to-noise ratio one obtains as a direct consequence of the larger amount of structure present in the higher harmonics, and thus a greater amount of information that can be obtained from that structure. We present the development of a novel technique where data at multiple harmonics is obtained simultaneously, rather than sequentially. This removes the susceptibility of the …
Oxygen Isotopes As A Tracer Of Dom Processes In River-Estuary Systems, Joy Ashley Matthews
Oxygen Isotopes As A Tracer Of Dom Processes In River-Estuary Systems, Joy Ashley Matthews
OES Theses and Dissertations
In the biogeochemical study of dissolved organic matter (DOM) in natural waters, stable isotopes are used to provide insight into both the sources of DOM and the processes affecting its alteration. Through the research presented here, oxygen isotopes are incorporated into the study of DOM through the adaptation of a pyrolysis elemental analysis isotope ratio mass spectrometer method, and sample preparation using two-stage ultrafiltration.
The application of oxygen isotopes to the study of DOM is demonstrated in two studies. First, natural abundance of δ18O in DOM is explored in the Delaware estuary. Using a two end-member mixing model, …
Semi-Parametric Likelihood Functions For Bivariate Survival Data, S. H. Sathish Indika
Semi-Parametric Likelihood Functions For Bivariate Survival Data, S. H. Sathish Indika
Mathematics & Statistics Theses & Dissertations
Because of the numerous applications, characterization of multivariate survival distributions is still a growing area of research. The aim of this thesis is to investigate a joint probability distribution that can be derived for modeling nonnegative related random variables. We restrict the marginals to a specified lifetime distribution, while proposing a linear relationship between them with an unknown (error) random variable that we completely characterize. The distributions are all of positive supports, but one class has a positive probability of simultaneous occurrence. In that sense, we capture the absolutely continuous case, and the Marshall-Olkin type with a positive probability of …
Apo B100 Similarities To Viral Proteins Suggest Basis For Ldl-Dna Binding And Transfection Capacity, Juan Guevara, Nagindra Prashad, Boris Ermolinsky, John W. Gaubatz, Dongcheul Kang, Andrea E. Schwarzbach, David S. Loose, Natalia Valentinova Guevara
Apo B100 Similarities To Viral Proteins Suggest Basis For Ldl-Dna Binding And Transfection Capacity, Juan Guevara, Nagindra Prashad, Boris Ermolinsky, John W. Gaubatz, Dongcheul Kang, Andrea E. Schwarzbach, David S. Loose, Natalia Valentinova Guevara
Physics and Astronomy Faculty Publications and Presentations
LDL mediates transfection with plasmid DNA in a variety of cell types in vitro and in several tissues in vivo in the rat. The transfection capacity of LDL is based on apo B100, as arginine/lysine clusters, suggestive of nucleic acid-binding domains and nuclear localization signal sequences, are present throughout the molecule. Apo E may also contribute to this capacity because of its similarity to the Dengue virus capsid proteins and its ability to bind DNA. Synthetic peptides representing two apo B100 regions with prominent Arg/Lys clusters were shown to bind DNA. Region 1 (0014Lys-Ser 0160) shares sequence motifs present in …
The Executable Command In Support Of Scheduled Subroutine Calls, Andrew Scott Lewis
The Executable Command In Support Of Scheduled Subroutine Calls, Andrew Scott Lewis
Electrical & Computer Engineering Theses & Dissertations
A potential solution to improving the utilization of increased thread level parallelism available in modern general purpose CPU's is the inclusion of a hardware scheduler. The hardware scheduler is designed to schedule subroutine calls based on a numerical condition in a high performance memory located on the CPU die, due to which the size of available memory is extremely limited. The main stumbling block in the development of a feasible hardware scheduler is the lack of a method of invoking a scheduled call using a single pointer. The use of a single pointer allows the limited size of the memory …
Action Recognition Based On Multi-Level Representation Of 3d Shape, Binu M. Nair
Action Recognition Based On Multi-Level Representation Of 3d Shape, Binu M. Nair
Electrical & Computer Engineering Theses & Dissertations
A novel algorithm is proposed in this thesis for recognizing human actions using a combination of two shape descriptors, one of which is a 3D Euclidean distance transform and the other based on the Radon transform. This combination captures the necessary variations from the space time shape for recognizing actions. The space time shapes are created by the concatenation of human body silhouettes across time. The comparisons are done against some common shape descriptors such as the zernike moments and Radon transform. This is also compared with an algorithm which uses the same concept of a space time shape and …
A Neighborhood Dependent Nonlinear Technique For Enhancement Of Color Images Captured Under Non-Uniform Lighting Conditions, Rupal Patel
Electrical & Computer Engineering Theses & Dissertations
The aim of image enhancement process is to improve the interpretability of the information in images for human viewers or to provide better input for automated image processing techniques. Many image processing applications begin with a nonlinear enhancement process to improve visual quality of video sequences captured under nonuniform lighting conditions. This improves the visibility of the scene captured from physical sensing devices which have limited dynamic range. This physical limitation causes the saturated region of the image to either shadow out or wash out the rest of the scene. When extremely bright and dark regions are present in an …
A Differential Absorption Model For Remote Sensing Of Atmospheric Pressure, Shivam J. Shah
A Differential Absorption Model For Remote Sensing Of Atmospheric Pressure, Shivam J. Shah
Electrical & Computer Engineering Theses & Dissertations
The goal of the project is to develop and test a "model based" radar processing strategy that is compatible with the concept of a "cognitive radar". The basic approach will be to develop a cognitive radar algorithm (genetic algorithm) based on the capabilities of an existing commercially available Software Radio. While the focus of this effort is the development of a candidate approach for genetic algorithm, the longer term goal would be to implement the approach using this software radio technology to provide a low cost radar processor. The proposed technology would use differential absorption radar working at the 50-56 …
Simulation Of Temperature Distributions In Tissue Upon Laser Pulse Irradiation Including Water Mass Transfer, Deepthi Nagulapally
Simulation Of Temperature Distributions In Tissue Upon Laser Pulse Irradiation Including Water Mass Transfer, Deepthi Nagulapally
Electrical & Computer Engineering Theses & Dissertations
Lasers, due to their unique characteristics, have tremendous applications in the medical field. Generally all laser applications in hie-medicine involve the propagation of laser energy through tissue. Energy is deposited giving rise to many physical, hie-chemical, and mechanical effects. Among these are dynamical changes in the local temperature distributions within the tissue. Analysis of the temperature changes requires the creation of an appropriate optical transmission and heat flow model that incorporates user specified laser parameters. Here, a numerical simulation model was developed to study both steady state and time dependent temperature distributions due to pulsed laser radiation within user specified …
The Mosquito (Diptera: Culicidae) Fauna Of The Blackwater Ecological Preserve: Effects Of Prescribed Burns And Habitat Type On Mosquito Abundance And Distribution, Norman A. Grefe Lll
The Mosquito (Diptera: Culicidae) Fauna Of The Blackwater Ecological Preserve: Effects Of Prescribed Burns And Habitat Type On Mosquito Abundance And Distribution, Norman A. Grefe Lll
Biological Sciences Theses & Dissertations
While mosquitoes (Diptera: Culicidae) are among the most studied of insect groups, much remains unknown about their distribution and response to environmental impacts such as prescribed burns. Blackwater Ecological Preserve, located near Zuni, Virginia, is a relict long leaf pine barren, parts of which undergo periodic prescribed burns to maintain and restore this fire-dependent ecosystem. To assess the impact of prescribed burns on mosquito activity and to determine associations between seasonal patterns of adult mosquito activity and habitat type, CDC light traps baited with dry ice were set (rom late April through October at Blackwater Ecological Preserve during the 2005 …
A Solution Of The Heat Equation With The Discontinuous Galerkin Method Using A Multilivel Calculation Method That Utilizes A Multiresolution Wavelet Basis, Robert Gregory Brown
A Solution Of The Heat Equation With The Discontinuous Galerkin Method Using A Multilivel Calculation Method That Utilizes A Multiresolution Wavelet Basis, Robert Gregory Brown
Mathematics & Statistics Theses & Dissertations
A numerical method to solve the parabolic problem is developed that utilizes the Discontinuous Galerkin Method for space and time discretization. A multilevel method is employed in the space variable. It is shown that use of this process yields the same level of accuracy as the standard Discontinuous Galerkin Method for the heat equation, but with cheaper computational cost. The results are demonstrated using a standard one-dimensional homogeneous heat problem.
Post-Processing Techniques And Wavelet Applications For Hammerstein Integral Equations, Khomsan Neamprem
Post-Processing Techniques And Wavelet Applications For Hammerstein Integral Equations, Khomsan Neamprem
Mathematics & Statistics Theses & Dissertations
This dissertation is focused on the varieties of numerical solutions of nonlinear Hammerstein integral equations. In the first part of this dissertation, several acceleration techniques for post-processed solutions of the Hammerstein equation are discussed. The post-processing techniques are implemented based on interpolation and extrapolation. In this connection, we generalize the results in [29] and [28] to nonlinear integral equations of the Hammerstein type. Post-processed collocation solutions are shown to exhibit better accuracy. Moreover, an extrapolation technique for the Galerkin solution of Hammerstein equation is also obtained. This result appears new even in the setting of the linear Fredholm equation.
In …
Your Local Cloud-Enabled Library, George K. Thiruvathukal
Your Local Cloud-Enabled Library, George K. Thiruvathukal
Computer Science: Faculty Publications and Other Works
Libraries are an important onramp for technology. They're known for making books accessible and have been pioneers in database access, but many branches seem to understand that they have a vital cultural role to play, especially when it comes to technology access. Most people in American society presume such access is ubiquitous, even though a substantial percentage of the world population lacks access.
Spectroscopic Study Of Ultracold Rubidium Atoms In An Optical Dipole Force Trap, Eman Mohammed Ahmed
Spectroscopic Study Of Ultracold Rubidium Atoms In An Optical Dipole Force Trap, Eman Mohammed Ahmed
Physics Theses & Dissertations
The interaction of light with atoms and molecules is of fundamental interest in many branches of science. In atomic physics, this interaction can be used to cool and spatially confine (trap) atoms. These traps can be used as the starting point for other experiments, but the dynamics of the cooling and trapping processes is itself of interest. In order to better understand the physics of trapping atoms in an optical dipole force trap, we have conducted a series of spectroscopic measurements of ultracold rubidium atoms in such a trap. The trap was created at the focus of a Nd:YAG laser …
Feasibility And Conceptual Design Of A C.W. Positron Source At Cebaf, Serkan Golge
Feasibility And Conceptual Design Of A C.W. Positron Source At Cebaf, Serkan Golge
Physics Theses & Dissertations
A feasibility study of a CW positron source for the 12 GeV upgrade at Jefferson Lab (JLAB) is provided. The proposed ≥ 100 nA Continuous Wave (CW) positron source at JLAB has several unique and challenging characteristics: high current incident electron beam at 126 MeV with a high beam power (up to a MW); CW e−beam and CW e+ production. The multiple scattering is a dominant process when creating e+ in a target, which results a large phase space area of the emitted positrons. An admittance study was done at CEBAF to find the maximum phase space area, which is …
Analytic Construction Of Periodic Orbits In The Restricted Three-Body Problem, Mohammed A. Ghazy
Analytic Construction Of Periodic Orbits In The Restricted Three-Body Problem, Mohammed A. Ghazy
Mechanical & Aerospace Engineering Theses & Dissertations
This dissertation explores the analytical solution properties surrounding a nominal periodic orbit in two different planes, the plane of motion of the two primaries and a plane perpendicular to the line joining the two primaries, in the circular restricted three-body problem. Assuming motion can be maintained in the plane and motion of the third body is circular, Jacobi's integral equation can be analytically integrated, yielding a closed-form expression for the period and path expressed with elliptic integral and elliptic function theory. In this case, the third body traverses a circular path with nonuniform speed. In a strict sense, the in-plane …
Evaluating Efficacy Of Restoration Techniques, Keys View Road Reconstruction, Joshua Tree National Park, California, U.S.A, Scott R. Abella, E. Cayenne Engel
Evaluating Efficacy Of Restoration Techniques, Keys View Road Reconstruction, Joshua Tree National Park, California, U.S.A, Scott R. Abella, E. Cayenne Engel
Public Policy and Leadership Faculty Publications
Keys View Road in Joshua Tree National Park (JOTR) was recently repaved, resulting in a buffer of vegetation and soil disturbance along the road corridor. In order to mitigate the effects of the repaving, JOTR designed an experimental framework to test various revegetation strategies. They outplanted salvaged and nursery grown native plant species in conjunction with vertical mulch in a fully crossed design (outplanting only, vertical mulch only, outplanting + vertical mulch, bare ground) to examine if any of the treatments most efficiently establish native plant communities.