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Electromechanics Of Biological Systems Studied By Scanning Probe Microscopy, Gary Thompson May 2011

Electromechanics Of Biological Systems Studied By Scanning Probe Microscopy, Gary Thompson

All Dissertations

The functional role of piezoelectricity and of other modes of electromechanical coupling across the hierarchical structures of biological materials garnered interest many years ago. Many biological materials have been described as exhibiting piezoelectric behavior, from wool fibers to wood planks and even to living mammalian cells, but efforts are on-going towards understanding how electromechanical coupling in biological systems transcends from the molecular to tissue levels.
In pursuit of high-resolution measurements of such hierarchical electromechanical coupling, scanning probe microscopy-based techniques are considered. Piezoresponse force microscopy (PFM) becomes the specific focus of this work, and the nascent development of PFM is reviewed …


Tight Polyhedral Representations Of Discrete Sets Using Projections, Simplices, And Base-2 Expansions, Stephen Henry May 2011

Tight Polyhedral Representations Of Discrete Sets Using Projections, Simplices, And Base-2 Expansions, Stephen Henry

All Dissertations

This research effort focuses on the acquisition of polyhedral outer-approximations to the convex hull of feasible solutions for mixed-integer linear and mixed-integer nonlinear programs. The goal is to produce desirable formulations that have superior size and/or relaxation strength. These two qualities often have great influence on the success of underlying solution strategies, and so it is with these qualities in mind that the work of this dissertation presents three distinct contributions.
The first studies a family of relatively unknown polytopes that enable the linearization of polynomial expressions involving two discrete variables. Projections of higher-dimensional convex hulls are employed to reduce …


Synthesis And Characterization Of Extended Solids Containing Nano-Sized Transition Metal Oxide Lattices, Matthew Williams May 2011

Synthesis And Characterization Of Extended Solids Containing Nano-Sized Transition Metal Oxide Lattices, Matthew Williams

All Dissertations

In this research, focus has been placed on the study of magnetic anomalies due to geometric frustration of magnetic ions. The goal of the study presented in this dissertation was to synthesize pseudo&ndashlow&ndashdimensional (PLD) compounds, those structures showing zero (dot), one (chain), and two (sheet) dimensional lattices observed in extended (3D) host frameworks with enhanced anisotropic physical properties, in an attempt to elucidate some structure&ndashproperty correlations arising from magnetic spin confinement. The scope of this research involved 1) exploratory synthesis of novel, low&ndashdimensional transition metal oxide lattices, specifically Mn and V, embedded in non&ndashmagnetic oxyanion frameworks, either Ge, P, or …


Implementation Of Delayed-Feedback Controllers On Continuous Systems And Analysis Of Their Response Under Primary Resonance Excitations, Yousef Qaroush May 2011

Implementation Of Delayed-Feedback Controllers On Continuous Systems And Analysis Of Their Response Under Primary Resonance Excitations, Yousef Qaroush

All Dissertations

During the last three decades, a considerable amount of research has been directed toward understanding the influence of time delays on the stability and stabilization
of dynamical systems. From a control perspective, these delays can either have a compounding and destabilizing effect, or can actually improve controllers'
performance. In the latter case, additional time delay is carefully and deliberately introduced into the feedback loop so as to augment inherent system delays and
produce larger damping for smaller control efforts. While delayed-feedback algorithms have been successfully implemented on discrete dynamical systems with
limited degrees of freedom, a critical issue appears in …


Assessment Of Conceptual Understanding Of Atomic Structure, Covalent Bonding, And Bond Energy, Alma Gonzales May 2011

Assessment Of Conceptual Understanding Of Atomic Structure, Covalent Bonding, And Bond Energy, Alma Gonzales

All Theses

This research work relied upon the importance of conceptual understanding to meaningful learning. Conceptual understanding is strongly influenced by students' prior knowledge (1). Many of these ideas pose strong barriers to deeper understanding and are called misconceptions since they are inconsistent or in conflict with generally accepted scientific facts (2). Thus, it is beneficial for instructors to initially elicit students' conceptual understanding in order to properly address student's misconceptions during the learning process. However, results are very dependent on the instrument used to elicit conceptual understanding (3). The most commonly used tools are summative assessments or achievement tests (4). They …


Agent-Based Under Hood Packing, Karthik Ravindranath May 2011

Agent-Based Under Hood Packing, Karthik Ravindranath

All Theses

Improving vehicle performance and passenger comfort has been a prime engineering concern and focus of research for many years in automotive design. Turning to high-performance components in an effort to improve vehicle performance alone is often not enough and their placement and interactions with other components should also be an integral part of the improvement process. With the advancement in hybrid electric vehicle technology, the packing of components under the hood is ever more essential and challenging. Under hood packing is a multi-objective optimization problem with many, and mostly conflicting objectives. A non-deterministic multi-objective evolutionary algorithm needs to be integrated …


Stereoscopic Simulation For Animation And Special Effects, Daniel Morella May 2011

Stereoscopic Simulation For Animation And Special Effects, Daniel Morella

All Theses

Stereoscopic content, when presented well, provides an exciting and entertaining experience for viewers. The advent of new techniques and technologies is helping stereoscopy to become more commonplace, with 3D movies becoming a staple at theaters around the world. Further, 3D televisions and content are poised to experience tremendous growth in the coming years. Even video games are exploring 3D content, with recent releases like Toy Story Mania as seen on the Disney website [Disn11].
The biggest problems with stereoscopic content are that it usually requires expensive hardware to view, and extensive time and technical prowess to create. These issues limit …


Predictive Modeling Of Wind Turbine Blades, Kendra Van Buren May 2011

Predictive Modeling Of Wind Turbine Blades, Kendra Van Buren

All Theses

Wind turbine blades are being produced at a larger scale in order to meet demands from the burgeoning U.S. wind energy industry, and are forecasted to only grow larger for off-shore applications. Modeling and Simulation (M&S) provides a cost and time efficient alternative when studying the structural behavior of blades such as for loading conditions that are too difficult to replicate in laboratory conditions, and for various severity of damage in wind turbine blades. For this reason, M&S will continue to play an indispensible role in understanding the behavior of wind turbine blades and is gradually replacing the traditional test, …


Kestrel: Job Distribution And Scheduling Using Xmpp, Lance Stout May 2011

Kestrel: Job Distribution And Scheduling Using Xmpp, Lance Stout

All Theses

A new distributed computing framework, named Kestrel, for Many-Task Computing
(MTC) applications and implementing Virtual Organization Clusters (VOCs) is
proposed. Kestrel is a lightweight, highly available system based on the
Extensible Messaging and Presence Protocol (XMPP), and has been developed to
explore XMPP-based techniques for improving MTC and VOC tolerance to faults due
to scaling and intermittently connected heterogeneous resources. Kestrel provides
a VOC with a special purpose scheduler for VOCs which can provide better scalability
under certain workload assumptions, namely CPU bound processes and bag-of-task
applications.
Experimental results have shown that Kestrel is capable of operating
a VOC of …


Development Of An On-Line Radiation Detection And Measurements Laboratory Course, Derick Kopp May 2011

Development Of An On-Line Radiation Detection And Measurements Laboratory Course, Derick Kopp

All Theses

An on-line radiation detection and measurements lab is being developed with a grant from the U.S. Nuclear Regulatory Commission. The on-line laboratory experiments are designed to provide a realistic laboratory experience and will be offered to students at colleges/universities where such a course is not offered. This thesis presents four web-based experiments: 1) nuclear electronics, 2) gamma-ray spectroscopy with scintillation detectors, 3) external gamma-ray dosimetry and gamma attenuation in matter, and 4) alpha spectroscopy and absorption in matter. The students access the experiments through a broad-band internet connection. Computer-controlled instrumentation developed in National Instruments (NI) LabVIEWTM communicates with the …


Nonadiabatic Generation Of A Pure Spin Current In A One-Dimensional Quantum Ring With Spin-Orbit Interaction, Marian Nita, D C. Marinescu, Andrei Manolescu, Vidar Gudmundsson Apr 2011

Nonadiabatic Generation Of A Pure Spin Current In A One-Dimensional Quantum Ring With Spin-Orbit Interaction, Marian Nita, D C. Marinescu, Andrei Manolescu, Vidar Gudmundsson

Publications

We demonstrate the theoretical possibility of obtaining a pure spin current in a 1D ring with spin-orbit interaction by irradiation with a nonadiabatic, two-component terahertz laser pulse, whose spatial asymmetry is reflected by an internal phase difference φ. The solutions of the equation of motion for the density operator are obtained for a spin-orbit coupling linear in the electron momentum (Rashba) and they are used to calculate the time-dependent charge and spin currents. We find that there are critical values of φ at which the charge current disappears, while the spin current reaches a maximum or a minimum value.


Detection Of Ch+ Emission From The Disc Around Hd 100546, W F. Thi, F Menard, G Meeus, C. Martin-Zaidi, P Woitke, E Tatulli, M Benisty, I Kamp, I Pascucci, C Pinte, C A. Grady, Sean D. Brittain, G J. White, C D. Howard, G Sandell, C Eiroa Apr 2011

Detection Of Ch+ Emission From The Disc Around Hd 100546, W F. Thi, F Menard, G Meeus, C. Martin-Zaidi, P Woitke, E Tatulli, M Benisty, I Kamp, I Pascucci, C Pinte, C A. Grady, Sean D. Brittain, G J. White, C D. Howard, G Sandell, C Eiroa

Publications

Despite its importance in the thermal balance of the gas and in the determination of primeval planetary atmospheres, the chemistry in protoplanetary discs remains poorly constrained with only a handful of detected species. We observed the emission from the disc around the Herbig Be star HD 100546 with the PACS instrument in the spectroscopic mode on board the Herschel Space Telescope as part of the GAS in Protoplanetary Systems (GASPS) programme and used archival data from the DIGIT programme to search for the rotational emission of CH+. We detected in both datasets an emission line centred at 72.16 μm that …


Perceptions Of Empowerment Of Participants Within Youth Development Programs, Kyle Busing Apr 2011

Perceptions Of Empowerment Of Participants Within Youth Development Programs, Kyle Busing

Journal of Youth Development

Highlighted in this paper is a study designed to investigate perceptions of empowerment among young 4-H club members. Participants included 90 boys and girls (mean age 10.61). Perceptions of the autonomy supportive nature of 4-H leaders and the general climate of 4-H clubs were assessed. MANCOVA analyses revealed participants perceived 4-H leaders and the general climate to be empowering. Although the young participants in this study confirmed some of the positive views found elsewhere in the literature, considerable disparities in their responses to various surveys were noted. There appeared to be uncertainty or misunderstanding among youngsters when asked to respond …


Hybrid Command Issuing In A 2-Dof Servomechanism Operated Under Vision-Based Feedback Control, C. Montes, C. Wong, J. Ziegert Apr 2011

Hybrid Command Issuing In A 2-Dof Servomechanism Operated Under Vision-Based Feedback Control, C. Montes, C. Wong, J. Ziegert

Publications

This paper presents a new method for generating motion commands in a 2 degree-of-freedom (DOF) vision-based position control system. The control system uses a fixed digital camera to direct-observe the multi-dimensional position of a known target displayed on an Liquid Cristal Display (LCD) and determines the position of the tool based on this information. This system, implemented on an XY-stage, was first introduced in Wong [1], and further investigated in Montes & Ziegert [2] and Montes et al. [3]. Previous results demonstrated sensor resolutions on the order of 3 µm; however the resolution of motion commands was constrained to values …


The Tiger Vol. 105 Issue 9 2011-04-01, Clemson University Apr 2011

The Tiger Vol. 105 Issue 9 2011-04-01, Clemson University

Tiger Newspapers

No abstract provided.


The Healing Species: Animal-Assisted Character Education For Improving Student Behavior, Wanda Pearson Apr 2011

The Healing Species: Animal-Assisted Character Education For Improving Student Behavior, Wanda Pearson

Journal of Youth Development

The Healing Species program aims to reduce disruptive behaviors at school by increasing students’ abilities to avoid conflict when possible and to resolve conflicts peaceably when they occur. The program’s 11 lessons incorporate elements of behavior theory that postulate behavior follows belief. This study hypothesized that 5th and 6th grade students who completed the Healing Species curriculum would show fewer normative beliefs favoring aggression, greater empathy, and fewer disciplinary infractions, than a comparable group of students who did not receive the Healing Species program. Lessons included the participation of rescued dogs to emphasize compassion, empathy, responsibility, and forgiveness. Study results …


Water Depletion In The Disk Atmosphere Of Herbig Aebe Stars, D Fedele, I Pascucci, Sean D. Brittain, I Kamp, P Woitke, J P. Williams, W.R.F. Dent, W F. Thi Mar 2011

Water Depletion In The Disk Atmosphere Of Herbig Aebe Stars, D Fedele, I Pascucci, Sean D. Brittain, I Kamp, P Woitke, J P. Williams, W.R.F. Dent, W F. Thi

Publications

We present high-resolution (R ∼ 100,000) L-band spectroscopy of 11 Herbig AeBe stars with circumstellar disks. The observations were obtained with the VLT/CRIRES to detect hot water and hydroxyl radical emission linespreviously detected in disks around T Tauri stars. OH emission lines are detected toward four disks. The OH 2Π3/2 P4.5 (1+,1−) doublet is spectrally resolved as well as the velocity profile of each component of the doublet. Its characteristic double-peak profile demonstrates that the gas is in Keplerian rotation and points to an emitting region extending out to ∼15–30 AU. The OH emission correlates with disk geometry as it …


The Unusual Protoplanetary Disk Around The T Tauri Star Et Chamaeleontis, P Woitke, B Riaz, G Duchene, I Pascucci, A Ran Lyo, W.R.F. Dent, N Phillips, W F. Thi, F Menard, G J. Herczeg, E Bergin, A Brown, A Mora, I Kamp, G Aresu, Sean D. Brittain, I De Gregorio-Monsalvo, G Sandell Mar 2011

The Unusual Protoplanetary Disk Around The T Tauri Star Et Chamaeleontis, P Woitke, B Riaz, G Duchene, I Pascucci, A Ran Lyo, W.R.F. Dent, N Phillips, W F. Thi, F Menard, G J. Herczeg, E Bergin, A Brown, A Mora, I Kamp, G Aresu, Sean D. Brittain, I De Gregorio-Monsalvo, G Sandell

Publications

We present new continuum and line observations, along with modelling, of the faint (6−8) Myr old T Tauri star ETCha belonging to the η Chamaeleontis cluster. We have acquired Herschel/PACS photometric fluxes at 70 μm and 160 μm, as well as a detection of the [OI] 63 μm fine-structure line in emission, and derived upper limits for some other far-IR OI, CII, CO and o-H2O lines. These observations were carried out in the frame of the open time key programme GASPS, where ETCha was selected as one of the science demonstration phase targets. The Herschel data is complemented by new …


The Tiger Vol. 105 Issue 6 2011-02-25, Clemson University Feb 2011

The Tiger Vol. 105 Issue 6 2011-02-25, Clemson University

Tiger Newspapers

No abstract provided.


The Nature Of "Dark" Gamma-Ray Bursts, J. Greiner, T. Krühler, S. Klose, P. Afonso, C. Clemens, R. Filgas, Dieter H. Hartmann, A. Küpcü Yoldas, M. Nardini, F. Olivares E., A Rau, A Rossi, P Schady, A Updike Feb 2011

The Nature Of "Dark" Gamma-Ray Bursts, J. Greiner, T. Krühler, S. Klose, P. Afonso, C. Clemens, R. Filgas, Dieter H. Hartmann, A. Küpcü Yoldas, M. Nardini, F. Olivares E., A Rau, A Rossi, P Schady, A Updike

Publications

Context. Thirteen years after the discovery of the first afterglows, the nature of dark gamma-ray bursts (GRB) still eludes explanation: while each long-duration GRB typically has an X-ray afterglow, optical/NIR emission is only seen for 40-60% of them. Aims. Here we use the afterglow detection statistics of the systematic follow-up observations performed with GROND since mid-2007 in order to derive the fraction of “dark bursts” according to different methods, and to distinguish between various scenarios for “dark bursts”. Methods. Observations were performed with the 7-channel “Gamma-Ray Optical and Near-infrared Detector” (GROND) at the 2.2m MPI/ESO telescope. We used the afterglow …


The Tiger Vol. 105 Issue 2 2011-01-28, Clemson University Jan 2011

The Tiger Vol. 105 Issue 2 2011-01-28, Clemson University

Tiger Newspapers

No abstract provided.


The Tiger Vol. 105 Issue 1 2011-01-21, Clemson University Jan 2011

The Tiger Vol. 105 Issue 1 2011-01-21, Clemson University

Tiger Newspapers 2011

No abstract provided.


The Tiger Vol. 105 Issue 1 2011-01-21, Clemson University Jan 2011

The Tiger Vol. 105 Issue 1 2011-01-21, Clemson University

Tiger Newspapers

No abstract provided.


Mathematical Sciences, Clemson University Jan 2011

Mathematical Sciences, Clemson University

Billing Rates

No abstract provided.


Common Data Set 2010-2011, Clemson University Jan 2011

Common Data Set 2010-2011, Clemson University

Common Data Sets

No abstract provided.


Auburn Vs Clemson (9/17/2011), Clemson University Jan 2011

Auburn Vs Clemson (9/17/2011), Clemson University

Football Programs

Auburn vs Clemson (9/17/2011)


The Tiger Career Fair Spring 2011, Clemson University Jan 2011

The Tiger Career Fair Spring 2011, Clemson University

Tiger Newspapers

No abstract provided.


Hydrodynamic Stability Of The Painted Turtle (Chrysemys Picta): Effects Of Four-Limbed Rowing Versus Forelimb Flapping In Rigid-Bodied Tetrapods. , Gabriel Rivera, Angela R.V. Rivera, Richard W. Blob Jan 2011

Hydrodynamic Stability Of The Painted Turtle (Chrysemys Picta): Effects Of Four-Limbed Rowing Versus Forelimb Flapping In Rigid-Bodied Tetrapods. , Gabriel Rivera, Angela R.V. Rivera, Richard W. Blob

Publications

Hydrodynamic stability is the ability to resist recoil motions of the body produced by destabilizing forces. Previous studies have suggested that recoil motions can decrease locomotor performance, efficiency and sensory perception and that swimming animals might utilize kinematic strategies or possess morphological adaptations that reduce recoil motions and produce more stable trajectories. We used high-speed video to assess hydrodynamic stability during rectilinear swimming in the freshwater painted turtle (Chrysemys picta). Parameters of vertical stability (heave and pitch) were non-cyclic and variable, whereas measures of lateral stability (sideslip and yaw) showed repeatable cyclic patterns. In addition, because freshwater and marine turtles …


Biodiesel Production From Crude Cottonseed Oil: An Optimization Process Using Response Surface Methodology, Xiaohu Fan, Xi Wang, Feng Chen Jan 2011

Biodiesel Production From Crude Cottonseed Oil: An Optimization Process Using Response Surface Methodology, Xiaohu Fan, Xi Wang, Feng Chen

Publications

Biodiesel, known as fatty acid methyl ester (FAME), was produced from crude cottonseed oil (triglycerides) by transesterification with methanol in the presence of sodium hydroxide. This process was optimized by applying factorial design and response surface methodology (RSM) with SAS and PSIPLOT programs. A second-order mathematical model was obtained to predict the yield as a function of methanol/oil molar ratio, catalyst concentration, reaction temperature, and rate of mixing. Based on ridge max analysis and RSM, as well as economic cost consideration, the practical optimal condition for the production of biodiesel was found to be: methanol/oil molar ratio, 7.9; temperature, 53 …


Origin: Metal Creation And Evolution From The Cosmic Dawn, J. W. Den Herder, L. Piro, T. Ohashi, C. Kouveliotou, Dieter H. Hartmann, J. Kaastra, L. Amati, M. I. Andersen, M. Arnaud, J.-L. Attéia Jan 2011

Origin: Metal Creation And Evolution From The Cosmic Dawn, J. W. Den Herder, L. Piro, T. Ohashi, C. Kouveliotou, Dieter H. Hartmann, J. Kaastra, L. Amati, M. I. Andersen, M. Arnaud, J.-L. Attéia

Publications

ORIGIN is a proposal for the M3 mission call of ESA aimed at the study of metal creation from the epoch of cosmic dawn. Using high-spectral resolution in the soft X-ray band, ORIGIN will be able to identify the physical conditions of all abundant elements between C and Ni to red-shifts of z=10, and beyond. The mission will answer questions such as: When were the first metals created? How does the cosmic metal content evolve? Where do most of the metals reside in the Universe? What is the role of metals in structure formation and evolution? To reach out to …