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2010 Summary Report On Institutional Effectiveness, Clemson University Aug 2010

2010 Summary Report On Institutional Effectiveness, Clemson University

Institutional Effectiveness Reports

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Spectroscopic Abundances And Membership In The Wolf 630 Moving Group, Eric J. Bubar, Jeremy R. King Aug 2010

Spectroscopic Abundances And Membership In The Wolf 630 Moving Group, Eric J. Bubar, Jeremy R. King

Publications

The concept of kinematic assemblages evolving from dispersed stellar clusters has remained contentious since Eggen’s initial formulation of moving groups in the 1960s. With high-quality parallaxes from the Hipparcos space astrometry mission, distance measurements for thousands of nearby, seemingly isolated stars are currently available. With these distances, a high-resolution spectroscopic abundance analysis can be brought to bear on the alleged members of these moving groups. If a structure is a relic of an open cluster, the members can be expected to be monolithic in age and abundance in as much as homogeneity is observed in young open clusters. In this …

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Locating The Accretion Footprint On A Herbig Ae Star: Mwc 480, C A. Grady, K Hamaguchi, G Schneider, B Stecklum, B E. Woodgate, J E. Mccleary, G M. Williger, M L. Sitko, F Menard, Th. Henning, Sean D. Brittain Aug 2010

Locating The Accretion Footprint On A Herbig Ae Star: Mwc 480, C A. Grady, K Hamaguchi, G Schneider, B Stecklum, B E. Woodgate, J E. Mccleary, G M. Williger, M L. Sitko, F Menard, Th. Henning, Sean D. Brittain

Publications

Accretion is a fundamental process which establishes the dynamics of the protoplanetary disk and the final properties of the forming star. In solar-type stars, the star–disk coupling is determined by the magnetic field structure, which is responsible for funneling material from the disk midplane to higher latitudes on the star. Here, we use pan-chromatic data for the Herbig Ae star MWC 480 to address whether similar processes occur in intermediatemass stars. MWC 480 has X-ray emission typical of actively accreting Herbig Ae stars, but with ∼10× more photoelectric absorption than expected from optical and FUV data. We consider three sources …

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Determination Of Higher Order Coefficients For A Crack Parallel To An Interface, Venkata Lakshman Kolluru Aug 2010

Determination Of Higher Order Coefficients For A Crack Parallel To An Interface, Venkata Lakshman Kolluru

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A general method based on the singular integral equations is developed to
computationally determine the higher order coefficients in mixed mode fracture
mechanics. These 'k' and 'T' coefficients are defined with respect to a polar coordinate
system centered at a crack tip, and give asymptotic expressions for stresses and
displacements according to the William's eigenfunction expansions,
(r, ) (2r) k f (n, ) k f (n, ) IIk
ij
II
n
Ik
ij
I
n
n 0
2
1
n
ij      



1
(0, ) (2 ) ( , ) ( , …

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Numerical Modeling Of Contaminant Transport In Fractured Porous Media Using Mixed Finite Element And Finite Volume Methods, Chen Dong Aug 2010

Numerical Modeling Of Contaminant Transport In Fractured Porous Media Using Mixed Finite Element And Finite Volume Methods, Chen Dong

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A mathematical model for contaminant species passing through fractured porous media is presented. In the numerical model, we combine two locally conservative methods, i.e. mixed finite element (MFE) and the finite volume methods. Adaptive triangle mesh is used for effective treatment of the fractures. A hybrid MFE method is employed to provide an accurate approximation of velocities field for both the fractures and matrix which are crucial to the convection part of the transport equation. The finite volume method and the standard MFE method are used to approximate the convection and dispersion terms respectively. Numerical examples in different fractured media …

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State Estimation For Diffusion Systems Using A Karhunen-Loeve-Galerkin Reduced-Order Model, Justin Mattimore Aug 2010

State Estimation For Diffusion Systems Using A Karhunen-Loeve-Galerkin Reduced-Order Model, Justin Mattimore

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This thesis focuses on generating a continuous estimate of state using a small number of sensors for a process modeled by the diffusion partial differential equation(PDE). In biological systems the diffusion of oxygen in tissue is well described by the diffusion equation, also known by biologists as Fick's first law. Mass transport of many other materials in biological systems are modeled by the diffusion PDE such as CO2, cell signaling factors, glucose and other biomolecules.
Estimating the state of a PDE is more formidable than that of a system described by ordinary differential equations (ODEs). While the state variables of …

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Metalloporphyrin-Catalyzed Reduction Reactions Of Hexavalent Chromium, Rong Zhang Aug 2010

Metalloporphyrin-Catalyzed Reduction Reactions Of Hexavalent Chromium, Rong Zhang

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Previous studies have demonstrated that the reduction of oxidized organic and inorganic contaminants could be catalyzed by electron shuttle systems, which generally were biological organic macrocycle complexes with transition metals. Metalloporphyrins (MPs) and their derivatives are well known electron shuttles for many biogeochemical systems. The objective of this research was to study the catalytic capabilities of selected MPs for the reduction of hexavalent chromium (Cr(VI)) in the presence of reducing agents. Zero valent iron (ZVI) was chosen as the primary electron donor in the experimental systems. Protoporphyrin IX (Proto) and Uroporphyrin I (Uro) are naturally occurring porphyrins produced during heme …

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Parametric Instabilities For Vibratory Energy Harvesting Under Harmonic, Time-Varying Frequency, And Random Excitations, Christopher Stabler Aug 2010

Parametric Instabilities For Vibratory Energy Harvesting Under Harmonic, Time-Varying Frequency, And Random Excitations, Christopher Stabler

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This effort investigates and evaluates the prospect of using parametric instabilities for vibratory energy harvesting. To that end, we consider a parametrically-excited piezoelectric cantilever beam and study its performance as an energy harvester under i) fixed-frequency harmonic excitations, ii) time-varying frequency excitations, and iii) band-limited Gaussian noise. In the case of fixed-frequency excitations, we use the Method of Multiple Scales to obtain approximate analytical expressions for the steady-state response amplitude and instantaneous output power in the vicinity of the first principle parametric resonance. We show that the electromechanical coupling and load resistance play an important role in determining the output …

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Institutionalization, Technology, And Power: The Ideological Context Of Style Organizations, Dustin Wilson Aug 2010

Institutionalization, Technology, And Power: The Ideological Context Of Style Organizations, Dustin Wilson

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Organizations have the power to establish the norms of discourse within various fields through organizational style guides. These style guides determine the conventions of discourse that professionals use every day. In this thesis, I explore and articulate the ideological context of some style guides in prominent professions. The institutionalization of discourse is seen through the history of style manuals and is particularly noted within the discourse of contemporary organizations that create style guides. Through an application of the theories of Foucault and Habermas, I discuss how these organizations institutionalize discourse and perpetuate a system of purposive-rational action. In this thesis, …

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The Effects Of Decoupled Payments On Production Decisions Under Base Acreage And Yield Updating Uncertainty: An Investigation Of Agricultural Chemical Use, Janet Peckham Aug 2010

The Effects Of Decoupled Payments On Production Decisions Under Base Acreage And Yield Updating Uncertainty: An Investigation Of Agricultural Chemical Use, Janet Peckham

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When first introduced, decoupled payments were thought to have minimal impacts on current production decisions and input use. In order to comply with the Uruguay Round Agreement on Agriculture requiring all World Trade Organization (WTO) member countries to reduce trade distorting agricultural policies, in 1996 U.S. agricultural policies began shifting away from coupled payments, based on current prices, production, or output, towards decoupled payments.
However, the literature has identified several mechanisms by which decoupled payments have the potential to distort production in the current period. First, risk averse producers may increase production due to insurance and wealth effects. Second, in …

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Willingness To Pay For Locally Grown And Organically Produced Fruits And Vegetables In Dominica, Seraphine George Aug 2010

Willingness To Pay For Locally Grown And Organically Produced Fruits And Vegetables In Dominica, Seraphine George

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ABSTRACT
With the intent of improving agricultural revenues and solidifying her place as an eco-tourism destination, it has been proposed that the island nation of The Commonwealth of Dominica convert all agricultural activities to organic production. To meet this challenge from the supply perspective, training of farmers in organic production practices has already begun. It remains, however, to quantify the potential demand for organically produced products. With this information in hand, appropriate producer support and marketing programs could be developed that would help to promote the production and consumption of Dominica‟s organic outputs and would propel Dominica toward its desired …

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Comparison Of Implied Volatility Approximations Using 'Nearest-To-The-Money' Option Premiums, Joseph Ewing Aug 2010

Comparison Of Implied Volatility Approximations Using 'Nearest-To-The-Money' Option Premiums, Joseph Ewing

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Implied volatility provides information which is useful for not only investors, but farmers, producers, manufacturers and corporations. These market participants use implied volatility as a measure of price risk for hedging and speculation decisions. Because volatility is a constantly changing variable, there needs to be a simple and quick way to extract its value from the Black-Scholes model. Unfortunately, there is no closed form solution for the extraction of the implied volatility variable; therefore its value must be approximated. This study investigated the relative accuracy of six methods for approximating Black-Scholes implied volatility developed by Curtis and Carriker, Brenner and …

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Factors Influencing The Adsorption Of Synthetic Organic Compounds By Carbon Nanotubes In Aquatic Environments, Ting Shao Aug 2010

Factors Influencing The Adsorption Of Synthetic Organic Compounds By Carbon Nanotubes In Aquatic Environments, Ting Shao

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Carbon nanotubes (CNTs) are allotropes of carbon consisting of sheets of carbon atoms covalently bonded in hexagonal arrays that are seamlessly rolled into a hollow, cy-lindrical shape with both ends rounded by fullerene-like caps. As large amounts of CNTs have been manufactured and significant growth is expected in commercial CNT produc-tion, there is a major concern over their health and environmental risks once they enter into the environment. In aquatic systems, CNTs are likely to adsorb organic chemicals and aggregate as bundles due to their extremely hydrophobic surfaces. The aggregation state of CNTs plays a significant role in their fate …

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Selection Of Channel-Access And Routing Protocols For Mobile Ad Hoc Networks With Frequency-Agile Radios And Directional Antennas, Rebekah Schloemann Aug 2010

Selection Of Channel-Access And Routing Protocols For Mobile Ad Hoc Networks With Frequency-Agile Radios And Directional Antennas, Rebekah Schloemann

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In this thesis, ad hoc networks with frequency-agile radios utilizing omni-directional and directional antennas form the basis of study. This work focuses on the selection of channel-access and routing protocols for these networks. Findings demonstrate that protocol selection must occur jointly in order to increase the efficient utilization of available spectrum while achieving maximum network performance.
In this thesis, we investigate several channel-access methods that provide different ways of selecting one of the heterogeneous non-overlapping channels for transmission. We also investigate a modification of least-resistance routing that accounts for the variations in transmission channels. Through simulation, we find that better …

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Community Ecology Approaches To Amphibian Conservation, Joanna Hawley Aug 2010

Community Ecology Approaches To Amphibian Conservation, Joanna Hawley

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Amphibian declines have been observed globally for several decades and populations continue to decline in many areas today. Through an extensive literature review of amphibian `impact studies,' I evaluated the use of multiple species, multiple spatial and temporal scales in an effort to ascertain a more complete, community-wide perspective on the causes of amphibian declines as well as management and conservation implications aimed at reversing these declines. Additionally, I performed multivariate analysis of an amphibian community dataset from southern Maine, USA using a multi-species and scalar approach to identify potentially important environmental variables associated with high levels of amphibian reproductive …

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Non-Contact Spatially Constrained Optical Scanning Methods Applied For Depth, Width And Gap Measurements, Konda Reddy Thotti Reddy Aug 2010

Non-Contact Spatially Constrained Optical Scanning Methods Applied For Depth, Width And Gap Measurements, Konda Reddy Thotti Reddy

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The thesis presents the non-contact laser projection based systems utilized for quantifying the feature dimensions like width, depth and air gaps. Laser diode, Charge coupled device (CCD) and post-processing software using image processing tools are the major components of the non-contact measurement systems. The study involves two methods where the first method comprises of active laser-based triangulation and morphological edge detection for depth and width measurement applications. The second method uses edge detection technique and Dynamic Field of View (DFOV) for gap detection and tracking. Using the developed techniques, the case studies are conducted with smooth plastic fenders with induced …

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Cultural Variation In The Visual Aspects Of Television Commercials: Comparing The Use And Effect Of Field Information In Chinese And Us Television Commercials, Jin Liu Aug 2010

Cultural Variation In The Visual Aspects Of Television Commercials: Comparing The Use And Effect Of Field Information In Chinese And Us Television Commercials, Jin Liu

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Cross-cultural psychology literature demonstrates cultural variation in visual perception patterns and field information inclusion in static visual designs between Chinese and American cultures. This study attempts to empirically investigate whether such variation exists in these two cultures' video images such as television commercials, and whether the commercials customized to cultural preference are more effective than others as previous research suggests. The research results correspond to previous claims about the visual design patterns in Chinese and American cultures, based on which suggestions for cinematic practice are provided. This research contends that variation in information inclusion and exclusion rules manifests differences in …

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Understanding The Role Of Electrostatics On Protein-Protein Binding, Rooplekha C Mitra Aug 2010

Understanding The Role Of Electrostatics On Protein-Protein Binding, Rooplekha C Mitra

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Ionized groups carry net charge and thus play a major role in the electrostatic interactions between the ligand and receptor. So understanding the role of electrostatics on protein-protein interactions is crucial for understanding the contribution of ionizable groups to the binding. However, their ionization states depend on many factors including pH of water phase. The complexity comes from the fact that the pKa's of ionizable groups may be quite different from their standard values and even may change due to protein-protein binding. The main difficulty in modeling plausible ionization changes induced by the complex formation arises from the differences in …

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Effect Of Abiotic Factors On Lead Corrosion In Drinking Water Systems, Bin Yang Aug 2010

Effect Of Abiotic Factors On Lead Corrosion In Drinking Water Systems, Bin Yang

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A major shift in water disinfection has been happening over the past few years from chlorination to chloramination. Chloramination is considered advantageous to chlorination due to the decreased formation of hazardous disinfection byproducts (DBPs) that are regulated by the Environmental Protection Agency (EPA) under the Disinfectants/Disinfection By-Products Rule. Despite the advantage of chloramination in generating less DBPs, unexpected increases in lead concentrations have recently been uncovered and receiving intensive attention. Because lead is neurologically toxic, research is needed to investigate the mechanisms involved in lead corrosion in such systems and to develop counteractive approaches. Currently, there is a very poor …

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Fantasy Football: Analyzing Fantasy Themes In America's Rhetorical Pastime, Frankie Christ Aug 2010

Fantasy Football: Analyzing Fantasy Themes In America's Rhetorical Pastime, Frankie Christ

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Fantasy football has emerged as a male-bonding experience of our online age. In understanding the formation of a rich rhetorical community, a close examination of how these fantasy football communities represent the larger culture is required. This thesis uses Ernest Bormann's theoretical framework of fantasy theme analysis to examine how the sharing of group fantasies creates a symbolic convergence. Once symbolic convergence has occurred, group members are then able to share rhetorical visions that shape their world's view. In the case of this thesis, Bormann's methods have been modified to better understand the small group dynamics of fantasy football participants. …

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Constructed Wetland Treatment Systems For Risk Mitigation Of Energy Derived Waters, Michael Spacil Aug 2010

Constructed Wetland Treatment Systems For Risk Mitigation Of Energy Derived Waters, Michael Spacil

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Energy derived waters (EDWs) (e.g. petroleum refinery effluents, produced waters) can contain a variety of constituents [e.g. selenium (Se), arsenic (As), low molecular weight organics (LMWOs)]. The overall objective of this research was to provide an approach for remediation of specific constituents of concern in these waters and to measure a relationship between Se removal and abundance of Se reducing microbes. The specific objectives of this research were to: (1) evaluate removal of Se from simulated refinery effluent (SRE) using a pilot-scale constructed wetland treatment system (CWTS); (2) evaluate removal of Se, As, and LMWOs from a generic simulated fresh …

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Modeling And Optimization Of A Plug-In Hybrid Electric Vehicle, Venkat Vijay Kishore Turlapati Aug 2010

Modeling And Optimization Of A Plug-In Hybrid Electric Vehicle, Venkat Vijay Kishore Turlapati

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Today, the world is faced with a situation where new technologies have to be developed to decrease the dependence on natural non-renewable resources. Each day, as the demand for non-renewable resources increases, it puts great pressure on the scientific fraternity to develop new technologies that are aimed at reducing this dependence.
Today's road traffic plays a major part in the energy consumption worldwide. Hence it is imperative that we develop environmentally friendly solutions to this problem that arises in the transportation sector. Hybrid vehicle is one of the alternatives that can be seen as a viable solution to this energy …

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Induction Assisted Thermography For Inspection Of Micro Defects On Sheet Metals, Sree Pamidi Aug 2010

Induction Assisted Thermography For Inspection Of Micro Defects On Sheet Metals, Sree Pamidi

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The work focuses on Induction assisted Thermography as a non-contact and non-destructive method of Inspecting micro defects on sheet metals used for making automotive body panels. Induction heating as a source of excitation to elevate the temperatures of sheet metals for uniform heating and detect ability of the defect is the main objective of the study.
Experiments are done on sheet metal samples with defects using excitation techniques like Pulse and Electromagnetic Induction. The thermal images obtained from the infrared camera are used to quantitatively analyze the detect ability of defects on sheet metals. The limitations of using Pulse technique …

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Design Method Development For The Design Of Traction Systems, Avinash Kolla Aug 2010

Design Method Development For The Design Of Traction Systems, Avinash Kolla

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The objective of this research is to develop a design method for rapid exploration of traction concepts primarily for off-road vehicles. Different approaches available to achieve this objective are discussed and compared, such as computational, analytical, and physical methods. Computational approaches are based on simulations performed using Finite Element Method (FEM), Discrete Element Method (DEM), and combined Finite Element-Discrete Element (FE-DE) methods. Analytical approaches are based on closed form mathematical models developed by previous researchers based on the theory of plasticity. Physical approaches include fabrication and testing of prototypes at different levels of abstraction. This thesis compares these different approaches …

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Hydromechanical Interference Slug Tests In A Fractured Biotite Gneiss, Trever Slack Aug 2010

Hydromechanical Interference Slug Tests In A Fractured Biotite Gneiss, Trever Slack

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Fractures are ubiquitous in the shallow crust and they commonly control the flow and storage of fluids in rock. Estimating transmission and storage properties resulting from fractures is commonly accomplished by interpreting the pressure signals caused by stressing an aquifer during a pumping or slug test. Fractures deform in response to pressure changes during well tests, and measuring and interpreting the deformation along with the pressure change is a way to potentially increase the information about storage and transmission properties. Tests where the pressure and deformation are coupled are called hydromechanical well tests. Previous investigations have focused on the effects …

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Quantum Codes From Two-Point Hermitian Codes, Justine Hyde-Volpe Aug 2010

Quantum Codes From Two-Point Hermitian Codes, Justine Hyde-Volpe

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We explore the background on error-correcting codes, including linear codes and quantum codes from curves. Then we consider the parameters of quantum codes constructed from two-point Hermitian codes.

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Developing A Management Tool To Estimate Unmarked Puma (Puma Concolor) Populations With A Remote Camera Array, Megan Pitman Aug 2010

Developing A Management Tool To Estimate Unmarked Puma (Puma Concolor) Populations With A Remote Camera Array, Megan Pitman

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Puma (Puma concolor) ecological research, puma management, and puma conservation require a technique to efficiently estimate puma populations. Adequate population estimates for pumas are difficult to produce due to natural history characteristics of the species. Remote camera arrays present a promising new tool for surveying cryptic mammals, but techniques for estimating population levels of unmarked animals or species that are difficult to individually identify in photographs are needed. Our goal was to develop techniques to (1) determine the camera effort needed to detect resident pumas with 95% certainty and (2) estimate puma population density for unmarked pumas with a remote …

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Contaminant Flow And Transport Simulation In Cracked Porous Media Using Locally Conservative Schemes, Pu Song Aug 2010

Contaminant Flow And Transport Simulation In Cracked Porous Media Using Locally Conservative Schemes, Pu Song

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The purpose of this paper is to analyze some features of contaminant flow passing through cracked porous media, such as the influence of fracture network on the advection and diffusion of contaminant species, the adsorption impact of contaminant wastes on the overall transport flow and so on. In order to precisely describe the whole process, we firstly need to build the mathematical model to simulate this problem numerically. Taking into consideration of the characteristics of contaminant flow, we employ two partial differential equations to formulate the whole problem. One is flow equation, the other is reactive transport equation. The first …

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Parallel √3-Subdivision With Animation In Consideration Of Geometric Complexity, Stephen Cooney Aug 2010

Parallel √3-Subdivision With Animation In Consideration Of Geometric Complexity, Stephen Cooney

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We look at the broader field of geometric subdivision and the emerging field of parallel computing for the purpose of creating higher visual fidelity at an efficient pace. Primarily, we present a parallel algorithm for √3-Subdivision. When considering animation, we find that it is possible to do subdivision by providing only one variable input, with the rest being considered static. This reduces the amount of data transfer required to continually update a subdividing mesh. We can support recursive subdivision by applying the technique in passes. As a basis for analysis, we look at performance in an OpenCL implementation that utilizes …

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Behavioral Animation For Maya Particles Using Steering Forces, Edgar Rodriguez Aug 2010

Behavioral Animation For Maya Particles Using Steering Forces, Edgar Rodriguez

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Maya has various built-in solutions for modeling effects. Maya does not, however, offer a built-in solution for modeling so called 'steering behaviors.' While users may rely on particle expressions or scene rigs, these solutions are generally time consuming and ultimately limiting in their cross application. Accordingly, Maya's particle system was extended, by implementing a new force, which can be used to model a set of steering behaviors. The new force was coded in Python and was implemented using Maya's Python Application Programming Interface ('API'). The new force can be used in conjunction with the particle system's existing forces and Maya's …

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