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Articles 1 - 16 of 16

Full-Text Articles in Physical Sciences and Mathematics

Broadcasting With Prediction And Selective Forwarding In Vehicular Networks, Jainjun Yang, Zongming Fei Dec 2013

Broadcasting With Prediction And Selective Forwarding In Vehicular Networks, Jainjun Yang, Zongming Fei

Computer Science Faculty Publications

Broadcasting in vehicular networks has attracted great interest in research community and industry. Broadcasting on disseminating information to individual vehicle beyond the transmission range is based on inter-vehicle communication systems. It is crucial to broadcast messages to other vehicles as fast as possible because the messages in vehicle communication systems are often emergency messages such as accident warning or alarm. In many current approaches, the message initiator or sender selects the node among its neighbors that is farthest away from it in the broadcasting direction and then assigns the node to rebroadcast the message once the node gets out of …


Is Security Sustainable?, Jeremy W. Crampton Aug 2013

Is Security Sustainable?, Jeremy W. Crampton

Geography Faculty Publications

No abstract provided.


Coupled Flow Field Simulations Of Charring Ablators With Nonequilibrium Surface Chemistry, Hicham Alkandry, Iain D. Boyd, Alexandre Martin Jun 2013

Coupled Flow Field Simulations Of Charring Ablators With Nonequilibrium Surface Chemistry, Hicham Alkandry, Iain D. Boyd, Alexandre Martin

Mechanical Engineering Faculty Publications

This paper describes the coupling of a Navier-Stokes solver to a material response code to simulate nonequilibrium gas-surface interactions. The Navier-Stokes solver used in this study is LeMANS, which is a three-dimensional computational fluid dynamics code that can simulate hypersonic reacting flows including thermo-chemical nonequilibrium effects. The material response code employed in this study is MOPAR, which uses the one-dimensional control volume nite-element method to model heat conduction and pyrolysis gas behavior. This coupling is demonstrated using a test case based on the Stardust sample return capsule. Coupled simulations are performed at three different trajectory conditions. The effects of the …


Volume Averaged Modeling Of The Oxidation Of Porous Carbon Fiber Material, Alexandre Martin Jun 2013

Volume Averaged Modeling Of The Oxidation Of Porous Carbon Fiber Material, Alexandre Martin

Mechanical Engineering Faculty Publications

Charring ablators remain the premium choice for space exploration missions that involve atmospheric re-entry. This type of ablative material is composed of a carbon matrix, usually made of fibers, which is then impregnated with a resin. During re-entry, the high heat flux produced by convective heating causes the material to chemically react. First, the resin pyrolyzes, and is vaporized into a gas that travels through the material, and is eventually ejected at the surface. Then, as the temperature rises, the surface of the porous matrix recess through ablative processes. For re-entry conditions typical of space exploration missions, this is mainly …


Multi-Dimensional Modeling Pyrolysis Gas Flow Inside Charring Ablators, Haoyue Weng, Alexandre Martin Jun 2013

Multi-Dimensional Modeling Pyrolysis Gas Flow Inside Charring Ablators, Haoyue Weng, Alexandre Martin

Mechanical Engineering Faculty Publications

Using an ablative thermal/material response code, the importance of three-dimensionality for modeling ablative test-article is addressed. In particular, the simulation of the pyrolysis gas flow inside a porous material is presented, using two different geometries. The effects of allowing the gas to flow out of the side wall are especially highlighted. Results show that the flow inside the test-article is complex, and that the 0D or 1D assumption made in most Material Response (MR) codes might not be valid for certain geometries.


Comparison Of Models For Mixture Transport Properties For Numerical Simulations Of Ablative Heat-Shields, Hicham Alkandry, Iain D. Boyd, Alexandre Martin Jan 2013

Comparison Of Models For Mixture Transport Properties For Numerical Simulations Of Ablative Heat-Shields, Hicham Alkandry, Iain D. Boyd, Alexandre Martin

Mechanical Engineering Faculty Publications

The goal of this study is to evaluate the effects of different models for calculating the mixture transport properties on flowfield predictions of ablative heat-shields. The Stardust sample return capsule at four different trajectory conditions is used as a test case for this study. In the first part of the study, the results predicted using Wilke's mixing rule with species viscosities calculated using Blottner's curve fits and species thermal conductivities determined using Eucken's relation are compared to the results obtained using Gupta's mixing rule with collision cross-section (CCS) data. The Wilke/Blottner/Eucken model overpredicts the heat transfer to the surface relative …


Modeling Of Chemical Nonequilibrium Effects In A Charring Ablator, Alexandre Martin Jan 2013

Modeling Of Chemical Nonequilibrium Effects In A Charring Ablator, Alexandre Martin

Mechanical Engineering Faculty Publications

Charring ablators remain the premium choice for space exploration missions that involve atmospheric re-entry. These type of ablative material are composed of a carbon matrix, usually made of fibers, which is then impregnated with a resin. During re-entry, the high heat flux produced by convective heating causes the material to chemically react. First, the resin pyrolyzes, and is vaporized into a gas that travels through the material, and is eventually ejected at the surface. Since the composition of the gas at the surface greatly affects the heat flux, and therefore the surface temperature, it is thus important to be able …


Application Of Swarm And Reinforcement Learning Techniques To Requirements Tracing, Hakim Sultanov Jan 2013

Application Of Swarm And Reinforcement Learning Techniques To Requirements Tracing, Hakim Sultanov

Theses and Dissertations--Computer Science

Today, software has become deeply woven into the fabric of our lives. The quality of the software we depend on needs to be ensured at every phase of the Software Development Life Cycle (SDLC). An analyst uses the requirements engineering process to gather and analyze system requirements in the early stages of the SDLC. An undetected problem at the beginning of the project can carry all the way through to the deployed product.

The Requirements Traceability Matrix (RTM) serves as a tool to demonstrate how requirements are addressed by the design and implementation elements throughout the entire software development lifecycle. …


Blackops: Increasing Confidence In Variant Detection Through Mappability Filtering, Christopher R. Cabanski, Matthew D. Wilkerson, Matthew Soloway, Joel S. Parker, Jinze Liu, Jan F. Prins, J. S. Marron, Charles M. Perou, D. Neil Hayes Jan 2013

Blackops: Increasing Confidence In Variant Detection Through Mappability Filtering, Christopher R. Cabanski, Matthew D. Wilkerson, Matthew Soloway, Joel S. Parker, Jinze Liu, Jan F. Prins, J. S. Marron, Charles M. Perou, D. Neil Hayes

Computer Science Faculty Publications

Identifying variants using high-throughput sequencing data is currently a challenge because true biological variants can be indistinguishable from technical artifacts. One source of technical artifact results from incorrectly aligning experimentally observed sequences to their true genomic origin (‘mismapping’) and inferring differences in mismapped sequences to be true variants. We developed BlackOPs, an open-source tool that simulates experimental RNA-seq and DNA whole exome sequences derived from the reference genome, aligns these sequences by custom parameters, detects variants and outputs a blacklist of positions and alleles caused by mismapping. Blacklists contain thousands of artifact variants that are indistinguishable from true variants and, …


Diffsplice: The Genome-Wide Detection Of Differential Splicing Events With Rna-Seq, Yin Hu, Yan Huang, Ying Du, Christian F. Orellana, Darshan Singh, Amy R. Johnson, Anaïs Monroy, Pei-Fen Kuan, Scott M. Hammond, Liza M. Hammond, Scott H. Randell, Derek Y. Chiang, D. Neil Hayes, Corbin Jones, Yufeng Liu, Jan F. Prins, Jinze Liu Jan 2013

Diffsplice: The Genome-Wide Detection Of Differential Splicing Events With Rna-Seq, Yin Hu, Yan Huang, Ying Du, Christian F. Orellana, Darshan Singh, Amy R. Johnson, Anaïs Monroy, Pei-Fen Kuan, Scott M. Hammond, Liza M. Hammond, Scott H. Randell, Derek Y. Chiang, D. Neil Hayes, Corbin Jones, Yufeng Liu, Jan F. Prins, Jinze Liu

Computer Science Faculty Publications

The RNA transcriptome varies in response to cellular differentiation as well as environmental factors, and can be characterized by the diversity and abundance of transcript isoforms. Differential transcription analysis, the detection of differences between the transcriptomes of different cells, may improve understanding of cell differentiation and development and enable the identification of biomarkers that classify disease types. The availability of high-throughput short-read RNA sequencing technologies provides in-depth sampling of the transcriptome, making it possible to accurately detect the differences between transcriptomes. In this article, we present a new method for the detection and visualization of differential transcription. Our approach does …


Excel Tips And Tricks Handout, Julene L. Jones Jan 2013

Excel Tips And Tricks Handout, Julene L. Jones

Julene L. Jones

Handout given at UK Libraries' Third Thursday: "Excel tips and tricks"


Visual Semantic Segmentation And Its Applications, Jizhou Gao Jan 2013

Visual Semantic Segmentation And Its Applications, Jizhou Gao

Theses and Dissertations--Computer Science

This dissertation addresses the difficulties of semantic segmentation when dealing with an extensive collection of images and 3D point clouds. Due to the ubiquity of digital cameras that help capture the world around us, as well as the advanced scanning techniques that are able to record 3D replicas of real cities, the sheer amount of visual data available presents many opportunities for both academic research and industrial applications. But the mere quantity of data also poses a tremendous challenge. In particular, the problem of distilling useful information from such a large repository of visual data has attracted ongoing interests in …


Automatic Detection Of Abnormal Behavior In Computing Systems, James Frank Roberts Jan 2013

Automatic Detection Of Abnormal Behavior In Computing Systems, James Frank Roberts

Theses and Dissertations--Computer Science

I present RAACD, a software suite that detects misbehaving computers in large computing systems and presents information about those machines to the system administrator. I build this system using preexisting anomaly detection techniques. I evaluate my methods using simple synthesized data, real data containing coerced abnormal behavior, and real data containing naturally occurring abnormal behavior. I find that the system adequately detects abnormal behavior and significantly reduces the amount of uninteresting computer health data presented to a system administrator.


A Robust Rgb-D Slam System For 3d Environment With Planar Surfaces, Po-Chang Su Jan 2013

A Robust Rgb-D Slam System For 3d Environment With Planar Surfaces, Po-Chang Su

Theses and Dissertations--Electrical and Computer Engineering

Simultaneous localization and mapping is the technique to construct a 3D map of unknown environment. With the increasing popularity of RGB-depth (RGB-D) sensors such as the Microsoft Kinect, there have been much research on capturing and reconstructing 3D environments using a movable RGB-D sensor. The key process behind these kinds of simultaneous location and mapping (SLAM) systems is the iterative closest point or ICP algorithm, which is an iterative algorithm that can estimate the rigid movement of the camera based on the captured 3D point clouds. While ICP is a well-studied algorithm, it is problematic when it is used in …


Context Aware Privacy Preserving Clustering And Classification, Nirmal Thapa Jan 2013

Context Aware Privacy Preserving Clustering And Classification, Nirmal Thapa

Theses and Dissertations--Computer Science

Data are valuable assets to any organizations or individuals. Data are sources of useful information which is a big part of decision making. All sectors have potential to benefit from having information. Commerce, health, and research are some of the fields that have benefited from data. On the other hand, the availability of the data makes it easy for anyone to exploit the data, which in many cases are private confidential data. It is necessary to preserve the confidentiality of the data. We study two categories of privacy: Data Value Hiding and Data Pattern Hiding. Privacy is a huge concern …


A Novel Computational Framework For Transcriptome Analysis With Rna-Seq Data, Yin Hu Jan 2013

A Novel Computational Framework For Transcriptome Analysis With Rna-Seq Data, Yin Hu

Theses and Dissertations--Computer Science

The advance of high-throughput sequencing technologies and their application on mRNA transcriptome sequencing (RNA-seq) have enabled comprehensive and unbiased profiling of the landscape of transcription in a cell. In order to address the current limitation of analyzing accuracy and scalability in transcriptome analysis, a novel computational framework has been developed on large-scale RNA-seq datasets with no dependence on transcript annotations. Directly from raw reads, a probabilistic approach is first applied to infer the best transcript fragment alignments from paired-end reads. Empowered by the identification of alternative splicing modules, this framework then performs precise and efficient differential analysis at automatically detected …