Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network™

Open Access. Powered by Scholars. Published by Universities.®

Clemson University

Discipline
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 3361 - 3390 of 5673

Full-Text Articles in Entire DC Network

Gas In The Protoplanetary Disc Of Hd 169142: Herschel's View, G Meeus, C Pinte, P Woitke, B Montesinos, I Mendigutia, P Riviere-Marichalar, C Eiroa, G S. Mathews, B Vandenbussche, C D. Howard, A Roberge, G Sandell, G Duchene, F Menard, C A. Grady, W.R.F. Dent, I Kamp, J C. Augereau, W F. Thi, I Tilling, J M. Alacid, S Andrews, D R. Ardila, G Aresu, D Barrado, Sean D. Brittain Jul 2010

Gas In The Protoplanetary Disc Of Hd 169142: Herschel's View, G Meeus, C Pinte, P Woitke, B Montesinos, I Mendigutia, P Riviere-Marichalar, C Eiroa, G S. Mathews, B Vandenbussche, C D. Howard, A Roberge, G Sandell, G Duchene, F Menard, C A. Grady, W.R.F. Dent, I Kamp, J C. Augereau, W F. Thi, I Tilling, J M. Alacid, S Andrews, D R. Ardila, G Aresu, D Barrado, Sean D. Brittain

Publications

In an effort to simultaneously study the gas and dust components of the disc surrounding the young Herbig Ae star HD 169142, we present far-IR observations obtained with the PACS instrument onboard the Herschel Space Observatory. This work is part of the open time key program GASPS, which is aimed at studying the evolution of protoplanetary discs. To constrain the gas properties in the outer disc, we observed the star at several key gas-lines, including [OI] 63.2 and 145.5 mum, [CII] 157.7 mum, CO 72.8 and 90.2 mum, and o-H2O 78.7 and 179.5 mum. We only detect the [OI] 63.2 …

Go to article

Development Of Experimental Methods To Assess Adsorption Free Energy For Peptide-Surface Interactions, Yang Wei Jul 2010

Development Of Experimental Methods To Assess Adsorption Free Energy For Peptide-Surface Interactions, Yang Wei

All Dissertations

Because of its governing role in cellular response to implants and substrates for biomedical applications, the understanding and control of protein adsorption to material surfaces has been one of the major topics of research in the field of biomaterials. Unfortunately, it has proven to be extremely difficult to quantitatively understand and control these types of interactions because of the complexities involved, and existing methods that have been developed and used to characterize protein-surface interactions have proved to be inadequate to provide the level of detail necessary to achieve this understanding. New, more fundamental methods, both experimental and computational, are needed …

Go to article

Novel Π-Conjugated Materials Plus Their Characterizations And Applications, Xiuxian He Jul 2010

Novel Π-Conjugated Materials Plus Their Characterizations And Applications, Xiuxian He

All Dissertations

The theme of this dissertation will focus on the syntheses and characterization of bipyridine (bipy) containing π-conjugated polymers (CPs). Specifically, poly(p-phenylene ethynylene), polyfluorene and poly(p-phenylene vinylene) derivatives have been prepared via Sonogashira coupling, Suzuki coupling and Heck coupling, respectively. Derivatives of poly(p-phenylene ethynylene), polyfluorene and poly(p-phenylene vinylene) are known to have applications in optical and electronic devices. Through this study, polymers condensed with bulky bipy-containing TAB as one of the copolymer units have shown increased solubility and diminished intrachain/interchain aggregation in solution and in film due to the effectiveness of TAB in controlling the relative orientations of individual polymer chains. …

Go to article

Center For Watershed Excellence - 2010 Spring/Summer News, Clemson University Jun 2010

Center For Watershed Excellence - 2010 Spring/Summer News, Clemson University

ICE Research News (Biannual Newsletter)

No abstract provided.

Go to article

On The Ph-Optimum Of Activity And Stability Of Proteins, Kemper Tally, Emil Alexov Jun 2010

On The Ph-Optimum Of Activity And Stability Of Proteins, Kemper Tally, Emil Alexov

Publications

Biological macromolecules evolved to perform their function in specific cellular environment (subcellular compartments or tissues); therefore, they should be adapted to the biophysical characteristics of the corresponding environment, one of them being the characteristic pH. Many macromolecular properties are pH dependent, such as activity and stability. However, only activity is biologically important, while stability may not be crucial for the corresponding reaction. Here, we show that the pH-optimum of activity (the pH of maximal activity) is correlated with the pH-optimum of stability (the pH of maximal stability) on a set of 310 proteins with available experimental data. We speculate that …

Go to article

Fe I And Fe Ii Abundances Of Solar-Type Dwarfs In The Pleiades Open Cluster, Simon C. Schuler, Adele L. Plunkett, Jeremy R. King, Marc H. Pinsonneault May 2010

Fe I And Fe Ii Abundances Of Solar-Type Dwarfs In The Pleiades Open Cluster, Simon C. Schuler, Adele L. Plunkett, Jeremy R. King, Marc H. Pinsonneault

Publications

We have derived Fe abundances of 16 solar-type Pleiades dwarfs by means of an equivalent width analysis of Fe I and Fe II lines in high-resolution spectra obtained with the Hobby - Eberly Telescope and High Resolution Spectrograph. Abundances derived from Fe II lines are larger than those derived from Fe I lines (herein referred to as over-ionization) for stars with Teff < 5400 K, and the dis-crepancy (∆Fe = [Fe II/H] - [Fe I/H]) increases dramatically with decreasing Teff, reaching over 0.8 dex for the coolest stars of our sample. The Pleiades joins the open clusters M34, the Hyades, IC2602, and IC2391, and the Ursa Major moving group, demonstrating ostensible over-ionization trends. The Pleiades ∆Fe abun-dances are correlated with Ca II infrared triplet and Hα chromospheric emission indicators and relative differences therein. Oxygen abundances of our Pleiades sample derived from the high-excitation O I triplet have been previously shown to increase with decreasing Teff, and a comparison with the ∆Fe abundances sug-gests that the over-excitation (larger abundances derived from high excitation lines relative to low excitation lines) and over-ionization effects that have been observed in cool open cluster and disk field main sequence (MS) dwarfs share a common origin. Curiously, a correlation between the Pleiades O I abundances and chromospheric emission indicators does not exist. Star-to-star Fe I abun-dances have low internal scatter (< 0.11 dex), but the abundances of stars with Teff< 5400 K are systematically higher compared to the warmer stars. The cool star [Fe I/H] abundances cannot be connected directly to over-excitation effects, but similarities with the ∆Fe and O I triplet trends suggest the abundances are dubious. Using the [Fe I/H] abundances of five stars with Teff > 5400 K, we derive a mean Pleiades cluster metallicity of [Fe/H] = +0.01 ± 0.02.

Go to article

Clemson Commencement Program, May 2010, Clemson University May 2010

Clemson Commencement Program, May 2010, Clemson University

Clemson Commencement Programs

No abstract provided.

Go to article

Co And H+3 Toward Mwc 1080, Mwc 349, And Lkhα 101, E L. Gibb, Sean D. Brittain, T W. Rettig, M Troutman, Theodore Simon, C Kulesa May 2010

Co And H+3 Toward Mwc 1080, Mwc 349, And Lkhα 101, E L. Gibb, Sean D. Brittain, T W. Rettig, M Troutman, Theodore Simon, C Kulesa

Publications

We present high-resolution, near-infrared NIRSPEC observations of the fundamental rovibrational CO and H+ 3 R(1,0), R(1,1) u , and Q(1,0) transitions toward three early-type young stars: MWC 1080, MWC 349, and LkHα 101. These observations were performed for the purpose of constraining the physical characteristics of the interstellar material along each line of sight. Toward MWC 1080, we detected strong CO absorption and determined a column density upper limit of 1.4 × 1014 cm–2 for H+ 3. We infer that there is very little diffuse material along the line of sight toward MWC 1080 and that the CO absorption is …

Go to article

Charleston History Through Architecture: Educating Students About Historic Preservation, Cultural Heritage, And Social History In Charleston, South Carolina, Katherine L. Stamps May 2010

Charleston History Through Architecture: Educating Students About Historic Preservation, Cultural Heritage, And Social History In Charleston, South Carolina, Katherine L. Stamps

Master of Science in Historic Preservation Terminal Projects

No abstract provided.

Go to article

Community Funding Models For Computational Resources, Amy Apon, Jeff Pummill, Dana Brunson May 2010

Community Funding Models For Computational Resources, Amy Apon, Jeff Pummill, Dana Brunson

Publications

As scientific research has extended far beyond the practicality and abilities of laboratory experiments, computational simulations have become the mainstay of enabling and furthering the research in a way never previously thought possible. It is becoming commonplace to model and simulate both the very large, such as black hole collisions in astrophysics, and the very small, such as subatomic particle behavior and interaction in high energy physics. In addition to the previous examples detailing extremes, practically every area of research currently utilizes and benefits from computational resources to simulate their work; financial modeling, weather forecasting, geological phenomena, geo-spatial data analysis, …

Go to article

Architecture Optimization, Training Convergence And Network Estimation Robustness Of A Fully Connected Recurrent Neural Network, Xiaoyu Wang May 2010

Architecture Optimization, Training Convergence And Network Estimation Robustness Of A Fully Connected Recurrent Neural Network, Xiaoyu Wang

All Dissertations

Recurrent neural networks (RNN) have been rapidly developed in recent years. Applications of RNN can be found in system identification, optimization, image processing, pattern reorganization, classification, clustering, memory association, etc.
In this study, an optimized RNN is proposed to model nonlinear dynamical systems. A fully connected RNN is developed first which is modified from a fully forward connected neural network (FFCNN) by accommodating recurrent connections among its hidden neurons. In addition, a destructive structure optimization algorithm is applied and the extended Kalman filter (EKF) is adopted as a network's training algorithm. These two algorithms can seamlessly work together to generate …

Go to article

Self-Assembly Of Architecturally Complex Block Copolymers, Juan Hinestrosa May 2010

Self-Assembly Of Architecturally Complex Block Copolymers, Juan Hinestrosa

All Dissertations

The term self-assembly denotes the formation of complex structures from simpler building blocks, resembling the manner in which Nature generates functional systems. In this pursuit, block copolymers present a great opportunity to study the interactions, dynamics and self-assembly of soft matter. Block copolymers have the ability to self-assemble into thermodynamically stable microphase segregated domains of precise shape and size, which are controlled by the chemistry of the constituent blocks, their size and connectivity, temperature and solvent conditions. Specifically, in this body of work two different types of branched copolymers with polystyrene (PS) and polyisoprene (PI) constituents are studied. The complex …

Go to article

Software Algorithms To Coordinate And Improve Voltage Sag Ridethrough Capabilities Of Networked Industrial Processes, Owen Parks May 2010

Software Algorithms To Coordinate And Improve Voltage Sag Ridethrough Capabilities Of Networked Industrial Processes, Owen Parks

All Dissertations

For those who design, operate, and troubleshoot industrial processes, electric power quality is a subject that requires much consideration. Processes that use electronic sensors, actuators, and computation devices are heavily reliant on a stable, consistent input power source. When a power quality event such as a voltage fluctuation occurs, automation equipment often behaves unpredictably and causes process malfunction or failure.
Because industrial power consumers often blame their electric utility for these events, some utilities offer process susceptibility studies as a service for their customers. During a typical study, utility technicians and engineers perform in-house tests on suspect components or systems …

Go to article

Chemical Characterization Of Botanical Products: Comprehensive Speciation By Liquid Chromatography Particle Beam Mass Spectrometry, Joaudimir Castro Georgi May 2010

Chemical Characterization Of Botanical Products: Comprehensive Speciation By Liquid Chromatography Particle Beam Mass Spectrometry, Joaudimir Castro Georgi

All Dissertations

The dietary supplement industry has expanded and many of these supplements have become an important aspect of people's everyday lives. In 1994, the U.S. Dietary Supplement Health and Education Act (DSHEA) classified numerous nutraceutical/botanical products as dietary supplements because of their beneficial medicinal properties and provided the necessary regulation to the supplement producers. Since then, the interest of the scientific community towards dietary supplements has grown intensively and numerous studies have been carried out in order to understand the chemical behavior of the active molecules in the human body. The development towards analytical methods for the quantification of the active …

Go to article

Vehicle Steering Systems - Hardware-In-The-Loop Simulator, Driving Preferences, And Vehicle Intervention, Jesse Black May 2010

Vehicle Steering Systems - Hardware-In-The-Loop Simulator, Driving Preferences, And Vehicle Intervention, Jesse Black

All Dissertations

The steering system is a critical component of all ground vehicles regardless of their propulsion source. Chassis directional control is provided by the steering system, which in turn relays valuable feedback about the road and vehicle behavior. As the primary feedback channel to the driver, the steering system also delivers the initial perception of a vehicle's handling and responsiveness to the consumer. Consequently, the steering system is an important aspect of the vehicle's evaluation and purchasing process, even if drivers are unaware of its direct influence in their decision making. With automobile purchases potentially hinging on the steering system, a …

Go to article

Pslr(1): Pseudo-Scannerless Minimal Lr(1) For The Deterministic Parsing Of Composite Languages, Joel Denny May 2010

Pslr(1): Pseudo-Scannerless Minimal Lr(1) For The Deterministic Parsing Of Composite Languages, Joel Denny

All Dissertations

Composite languages are composed of multiple sub-languages. Examples include the parser specification languages read by parser generators like Yacc, modern extensible languages with complex layers of domain-specific sub-languages, and even traditional programming languages like C and C++. In this dissertation, we describe PSLR(1), a new scanner-based LR(1) parser generation system that automatically eliminates scanner conflicts typically caused by language composition. The fundamental premise of PSLR(1) is the pseudo-scanner, a scanner that only recognizes tokens accepted by the current parser state. However, use of the pseudo-scanner raises several unique challenges, for which we describe a novel set of solutions. One major …

Go to article

Mobility Of Plutonium In Zea Mays (Corn): Determination Of Transport Velocities, Spatial Distribution And Correlations With Iron., Shannon Thompson May 2010

Mobility Of Plutonium In Zea Mays (Corn): Determination Of Transport Velocities, Spatial Distribution And Correlations With Iron., Shannon Thompson

All Dissertations

Understanding the environmental behavior of plutonium (Pu) is essential for proper radioactive waste disposal or for remedial activities following an accidental release of Pu. The environmental behavior of Pu is influenced by physical, chemical, and biotic factors, such as the simultaneous existence of multiple Pu species, redox transformations at mineral surfaces, colloid formation, and the potential of microbes and plants to affect its sorption to soil. Plant Pu studies have been conducted for quantifying bioaccumulation or phytoremediation. Until now, experimental studies have not focused on the capacity of plants to affect the transport behavior and distribution of Pu in the …

Go to article

A Lyapunov Based Approach To Energy Maximization In Renewable Energy Technologies, Erhun Iyasere May 2010

A Lyapunov Based Approach To Energy Maximization In Renewable Energy Technologies, Erhun Iyasere

All Dissertations

This dissertation describes the design and implementation of Lyapunov-based control strategies for the maximization of the power captured by renewable energy harnessing technologies such as (i) a variable speed, variable pitch wind turbine, (ii) a variable speed wind turbine coupled to a doubly fed induction generator, and (iii) a solar power generating system charging a constant voltage battery.
First, a torque control strategy is presented to maximize wind energy captured in variable speed, variable pitch wind turbines at low to medium wind speeds. The proposed strategy applies control torque to the wind turbine pitch and rotor subsystems to simultaneously control …

Go to article

Source Optimization In Abstract Function Spaces For Maximizing Distinguishability: Applications To The Optical Tomography Inverse Problem, Bonnie Jacob May 2010

Source Optimization In Abstract Function Spaces For Maximizing Distinguishability: Applications To The Optical Tomography Inverse Problem, Bonnie Jacob

All Dissertations

The focus of this thesis is to formulate an optimal source problem for the medical imaging technique of optical tomography by maximizing certain distinguishability criteria. We extend the concept of distinguishability in electrical impedance tomography to the frequency-domain diffusion approximation model used in optical tomography.
We consider the dependence of the optimal source on the choice of appropriate function spaces, which can be chosen from certain Sobolev or Lp spaces. All of the spaces we consider are Hilbert spaces; we therefore exploit the inner product in several ways. First, we define and use throughout an inner product on the Sobolev …

Go to article

Dynamics Groups Of Asynchronous Cellular Automata, Michael Macauley, Jon Mccammond, Henning S. Mortveit May 2010

Dynamics Groups Of Asynchronous Cellular Automata, Michael Macauley, Jon Mccammond, Henning S. Mortveit

Publications

We say that a finite asynchronous cellular automaton (or more generally, any sequential dynamical system) is π-independent if its set of periodic points are independent of the order that the local functions are applied. In this case, the local functions permute the periodic points, and these permutations generate the dynamics group. We have previously shown that exactly 104 of the possible 223 = 256 cellular automaton rules are π-independent. In the article, we classify the periodic states of these systems and describe their dynamics groups, which are quotients of Coxeter groups. The dynamics groups provide information …

Go to article

Examining The Behavioral Intentions Of Older Adults As Virtual Tourists In The Context Of A Second Life Destination, Dorinda Christian May 2010

Examining The Behavioral Intentions Of Older Adults As Virtual Tourists In The Context Of A Second Life Destination, Dorinda Christian

All Dissertations

ABSTRACT
Tourism opportunities are being promoted heavily on the web, yet one of the largest and most lucrative markets, older adults are least likely to use the internet. In an effort to explore barriers to and potential acceptance of technology for tourism experiences, this study followed closely ten older adults through a learning process with technology. Qualitative methodology was used to explore in-depth the experience of these older adults being exposed to online virtual world technology for the first time and exploring the process by which technology acceptance takes place. The findings indicate that online virtual world such as Second …

Go to article

The Accuracy Of Observers' Estimates Of The Effect Of Glare On Nighttime Vision: Do We Exaggerate The Disabling Effects Of Glare?, Stacy Balk May 2010

The Accuracy Of Observers' Estimates Of The Effect Of Glare On Nighttime Vision: Do We Exaggerate The Disabling Effects Of Glare?, Stacy Balk

All Dissertations

Designing headlights involves balancing two conflicting goals: maximizing visibility for the driver and minimizing the disabling effects of glare for other drivers. Complaints of headlight glare have increased recently. This project explored the relationship between subjective (discomfort and expected visual problems) and objective (actual visual problems) consequences of glare. Two experiments - a lab-based psychophysical study and a field study - quantified the accuracy of observers' estimates of the effects of glare on their acuity. In both experiments, participants over-estimated the extent to which glare degraded their ability to see a small high contrast target. Observers' estimates of the disabling …

Go to article

The College Football Student-Athlete's Academic Experience: Network Analysis And Model Development, Kyle Young May 2010

The College Football Student-Athlete's Academic Experience: Network Analysis And Model Development, Kyle Young

All Dissertations

A grounded theory research study employing network analysis as a means of facilitating the latter stages of the coding process was conducted at a selective university that competes at the highest level of college football. The purpose of the study was to develop a better understanding of how interactive dynamics and controlling mechanisms, such as NCAA eligibility standards, influence the academic experience of college football student-athletes. The study resulted in the development of a model that depicted the college football student-athlete's academic experience along a path of engagement that is influenced by dynamics and processes over the course of his …

Go to article

Creating A Biomedical Ontology Indexed Search Engine To Improve The Semantic Relevance Of Retreived Medical Text, William Taylor Ii May 2010

Creating A Biomedical Ontology Indexed Search Engine To Improve The Semantic Relevance Of Retreived Medical Text, William Taylor Ii

All Dissertations

Medical Subject Headings (MeSH) is a controlled vocabulary used by the National Library of Medicine to index medical articles, abstracts, and journals contained within the MEDLINE database. Although MeSH imposes uniformity and consistency in the indexing process, it has been proven that using MeSH indices only result in a small increase in precision over free-text indexing. Moreover, studies have shown that the use of controlled vocabularies in the indexing process is not an effective method to increase semantic relevance in information retrieval.
To address the need for semantic relevance, we present an ontology-based information retrieval system for the MEDLINE collection …

Go to article

Kinetic And Finite Element Modeling For Firing Brick, Daniel Mckinney May 2010

Kinetic And Finite Element Modeling For Firing Brick, Daniel Mckinney

All Theses

Kinetic modeling and simulation were used to optimize the firing cycle for brick. This was done to develop a tool for the brick industry to reduce fuel consumption and emissions during firing. A kinetic model was built using shrinkage data from dilatometer measurements and mass loss data from thermogravimetry measurements in order to predict the density as a function of temperature and time. The density of brick was related to the absorption coefficient (C/B), an ASTM standard which is related to the durability of the brick. The kinetic model was used to optimize the firing curve using a rate controlled …

Go to article

Conservation Biology Of The Diamondback Terrapin In North America, Amanda Hackney May 2010

Conservation Biology Of The Diamondback Terrapin In North America, Amanda Hackney

All Theses

Reptiles are experiencing global declines and pond turtles (Emydidae) are particularly vulnerable. The diamondback terrapin uses multiple habitats to fulfill its life history requirements, in the estuarine environments of the Gulf Coast and Atlantic states (US). Interacting effects of coastal development, overharvesting, abandoned crabbing gear, road mortality, climate change, and nest predation are likely causing population declines throughout its distribution. Protection levels were assessed by referencing each state's Wildlife Action Plan for the species' Conservation Status Ranking Code. At least 7 federal laws directly or indirectly regulate take, wetland, and/or coastal activities (Lacey Act, CWA, FWCA, NAWCA, WPFPA, CBRA, NEPA). …

Go to article

Comparison Of Rna Quality From Stressed And Unstressed Recombinant Escherichia Coli, Mary Alice Salazar May 2010

Comparison Of Rna Quality From Stressed And Unstressed Recombinant Escherichia Coli, Mary Alice Salazar

All Theses

High quality, intact RNA is required for DNA microarray studies, cloning, and reverse transcriptase polymerase chain reaction (rt-PCR) analysis. There are several analytical methods used to assess the RNA quality. The RNA Integrity Number (RIN) from the Agilent Bioanalyzer is one quality control assay used to evaluate RNA. For recombinant Escherichia coli cultured under stressful conditions the RNA profiles obtained using the Agilent Bioanalyzer indicate RNA degradation; however, RNA obtained and purified in parallel from unstressed recombinant cultures indicate acceptable RNA values without significant degradation. We proposed that for stressed E. coli the RIN value is not necessarily indicative of …

Go to article

Comprehensive Analysis Of A Student-Centered Active-Learning Integrated Statics And Dynamics Course For Mechanical Engineers, Marisa Orr May 2010

Comprehensive Analysis Of A Student-Centered Active-Learning Integrated Statics And Dynamics Course For Mechanical Engineers, Marisa Orr

All Theses

The Student-Centered Active Learning in Undergraduate Programs (SCALE-UP) approach to instructional design was adapted with the goal of delivering more effective statics, dynamics and multivariate calculus instruction and integrated course curricula. Inquiry-based learning exercises were designed, incorporating material from statics and dynamics into multivariable calculus, and vice-versa, as well as integrating statics and dynamics into one course. Analysis included an exploration of student study habits, multiple measures of course effectiveness, and an examination of curricular effects. Challenges of implementation are also discussed.
Study habits of students in an integrated Statics and Dynamics course were assessed through a voluntary survey in …

Go to article

Women As Sustainability Leaders In Engineering: Evidence From Industry And Academia, Jennilee Harrison May 2010

Women As Sustainability Leaders In Engineering: Evidence From Industry And Academia, Jennilee Harrison

All Theses

Women are underrepresented in engineering education and practice, which limits the quality of the engineering workforce. One way to increase the participation of women in engineering is to emphasize subjects that appeal to them and emphasize skills at which they are especially adept. A subject that may fit this description is sustainability. The purpose of this research is to compare the percentage of women in selected sustainable engineering leadership positions to the percentage of women in general engineering leadership positions, to examine whether the subject of sustainability may help increase participation of women in engineering. Gender data was collected for …

Go to article

Practical Implementation Of The Virtual Organization Cluster Model, Michael Fenn May 2010

Practical Implementation Of The Virtual Organization Cluster Model, Michael Fenn

All Theses

Virtualization has great potential in the realm of scientific computing because of its inherent advantages with regard to environment customization and isolation. Virtualization technology is not without it's downsides, most notably, increased computational overhead. This thesis introduces the operating mechanisms of grid technologies in general, and the Open Science Grid in particular, including a discussion of general organization and specific software implementation. A model for utilization of virtualization resources with separate administrative domains for the virtual machines (VMs) and the physical resources is then presented. Two well-known virtual machine monitors, Xen and the Kernel-based Virtual Machine (KVM), are introduced and …

Go to article

First Prev Next Last