Computational Engineering Commons^™

Testing, Modelling And Validation Of Numerical Model Capable Of Predicting Stress Fields Throughout Polyurethane Foam, Conor Briody, Barry Duignan, Stephen Jerrams

Conference Papers

Wheelchair seating systems are specialised for a number of reasons as users can have impaired mobility, which increases the possibility of pressure build up. These areas of high pressure frequently occur in the trunk region under the bony prominences known as the Ischial Tuberosities (IT), pressure ulcers may occur consequently. Polyurethane foam has been in use for some time in wheelchair seating systems as it exhibits good pressure relieving capabilities in most cases. However, little quantitative research has gone into foamed polymers, in comparison with conventional elastomeric materials. This lack of knowledge can ultimately lead to more time being spent …

Quantitative Characterization Of Microstructure Features For 1st Generation Advanced High Strength Steels, Margarita Vidrio, Ellen Liu, Donsheng Li, Kyoo Sil Choi, Xin Sun

STAR Program Research Presentations

The role of Advanced High Strength Steels (AHSS) in the automotive industry is important because of its affordability and excellent mechanical properties. The 1st generation of AHSS achieves its preferred combination of strength and ductility by embedding harder martensite grains into softer ferritic matrix. Ductility and strength of these steels are important to safety, formability, application, and life. However, a noticeable degree of inconsistent forming behaviors has been observed in the 1st generation AHSS in production, which seems to be related to the microstructure-level inhomogeneity. The objective of this project is to grain fundamental understandings on how different microstructure level …

Design Optimization Using Cad Parameterization Through Capri, William Emerson Brock V

Masters Theses and Doctoral Dissertations

Design optimization is one of the many areas of Computational Engineering that is directly applicable to almost any engineering endeavor. The design cycle is a multi-step process, beginning with a Computer Aided Design (CAD) model and ending with an optimized version of that model relative to some objective function. This is accomplished by parameterizing the model, through one of many different algorithms, and finding the ideal value of those parameters with respect to the specified objective. The purpose of this research is to explore the use of a Computational Analysis PRogramming Interface (CAPRI) for utilizing CAD parameters in design optimization …

An Adaptive Hybrid Mesh Generation Method For Complex Geometries, Cameron Thomas Druyor

Masters Theses and Doctoral Dissertations

An adaptive hybrid mesh generation method is described to automatically provide spatial discretizations suitable for computational fluid dynamics or other 2D solver applications. This method employs a hierarchical grid generation technique to create a background mesh, an extrusion-type method for inserting boundary layers, and an unstructured triangulation to stitch between the boundary layers and background mesh. This method provides appropriate mesh resolution based on geometry segments from a file, and has the capability of adapting the background mesh based on a spacing field generated from solution data or some other arbitrary source. By combining multiple approaches to the grid generation …

Generation And Optimization Of Spacing Fields, Max David Collao

Masters Theses and Doctoral Dissertations

Meshes are used to discretize space for computational fluid dynamics (CFD) simulations. Mesh adaptation through refinement and smoothing can improve the accuracy of the CFD solution. In order to perform adaptive refinement or smoothing a spacing field is needed to define the desired edge sized in mesh. The objectives of this research are to generate spacing fields from existing CFD solutions and optimize this spacing information for efficient use by programs to perform adaptive refinement or smoothing. All work was done on 2D meshes with the intention of gaining knowledge and experience for later application to 3D meshes. The program …

Computational Design For Electromagnetic Simulations, Ryan Steven Glasby

Masters Theses and Doctoral Dissertations

An automatic computational procedure has been developed to efficiently and accurately design the shape of complicated electromagnetic objects. These electromagnetic objects can be simulated for operation at high frequencies (~10 GHz), and can be comprised of dissimilar materials. The automated design procedure consists of linking together an original electromagnetic field simulation tool, an original adjoint routine for obtaining sensitivity derivatives, and an original grid-smoothing tool with an existing optimization package. The electromagnetic field simulation software employs a temporally and spatially higher-order accurate Streamline Upwind/Petrov-Galerkin finite-element method that numerically solves Maxwell’s equations in the time domain using implicit time stepping. The …

Comparison Of Two Methods For Two Dimensional Unstructured Mesh Adaptation With Elliptic Smoothing, Matthew David O'Connell

Masters Theses and Doctoral Dissertations

A new mesh adaptation method for unstructured grids is presented. The technique uses virtual control volumes that are iteratively manipulated to conform the mesh to match either a Riemannianmetric tensor field or an equal distribution of scalar weights. Forcing functions similar to those used for structured grids are employed such that the resulting meshes can be compared with those generated using the new adaptation method. Several test cases using analytic functions to drive the mesh adaptation are also presented and compared with the new method. Mesh adaptation results driven by computed flow field information are also compared to those adapted …

Characterization Of Parallel Application Runtime Sensitivity On Multi-Core High Performance Computing Systems, Padma Priya Veeraraghavan

Purdue Polytechnic Masters Theses

A commonly seen behavior of parallel applications is that their runtime is influenced by network communication load. The way a parallel application is run in a network and the presence of other applications and processes in the network can contribute to a wide range of variations in the runtime. Therefore, in order to achieve consistent and optimal runtimes, it is important to understand and characterize the runtime sensitivity of parallel applications with respect to execution under the presence of network communication load.

In this research, runtime sensitivities for various parallel applications were studied by applying additional network communication load. In …

The Ergo Knife Manufacturability Project: A Prosthetic Device, Caleb Sarris

Industrial and Manufacturing Engineering

Millions of Americans’ upper extremities have been rendered useless or amputated due to injury or illness. Without strength and dexterity in the hand or wrist, these people are in need of tools to help them in everyday activities. The Ergo Knife offers these individuals a way to cope with this way of life as a device that can assist them, primarily in food consumption and can also be expanded to many other applications. The purpose of this project is to further develop the Ergo Knife so that it can better assist these individuals and improve the necessary processes used to …

Cal Poly Wow: Week Of Welcome’S Leader Android Application, Eric Cerney

Computer Engineering

The Week of Welcome Android application aims to improve the efficiency and ease at which Orientation Leaders function during the week long program designed to aid in new student
assimilation to the San Luis Obispo campus and community. It focuses on four utilities combined in
one easy location that Leaders use on a regular basis. They are maps, the online guidebook, budget keeper, and contact list. These four utilities are commonly used by Leaders in their day to day
guidance of new students, making one single application with each tool very desirable to the WOW Program.

Currently there are no …

Chinese To English Introductory Cover Letter Generator, Jason L. Stine

Liberal Arts and Engineering Studies

The Chinese to English Introductory Cover Letter Generator allows Chinese computer users who know little to no English automatically generate a self-introductory cover letter in good English. As an example, professors in English-speaking countries are increasingly receiving emails from students abroad in countries like China, and these students often need to introduce themselves in order to support their reasons for their message. Unfortunately, more often than not these letters contain poorly written English. This software aims to help solve this issue. Using a combination of a “sentence template” system and intelligent natural language processing software, the program assembles each paragraph …

An Evaluation Of The Eeg Alpha-To-Theta And Theta-To-Alpha Band Ratios As Indexes Of Mental Workload, Bujar Raufi, Luca Longo

Articles

Many research works indicate that EEG bands, specifically the alpha and theta bands, have been potentially helpful cognitive load indicators. However, minimal research exists to validate this claim. This study aims to assess and analyze the impact of the alpha-to-theta and the theta-to-alpha band ratios on supporting the creation of models capable of discriminating self-reported perceptions of mental workload. A dataset of raw EEG data was utilized in which 48 subjects performed a resting activity and an induced task demanding exercise in the form of a multitasking SIMKAP test. Band ratios were devised from frontal and parietal electrode clusters. …

A Web-Oriented Multi-Layer Model To Interact With Theatrical Performances, A Baratè, G. Haus, L A. Ludovico, Davide Andrea Mauro

Computer Sciences and Electrical Engineering Faculty Research

This paper presents an innovative approach to online fruition

of theater performances. Web applications like traditional viewers are

already available for the wide audience of Internet users. Our proposal

aims at adding both interactivity and multi-layer fruition, and a way

to manipulate and create new media. The premise to reach these goals

is digitizing a number of heterogeneous materials in order to describe a

single performance comprehensively, e.g. different video and audio-takes

from different perspectives, and a number of related materials such as

scripts, fashion plates, playbills, etc. The format we adopt to encode

such information is based on the …

Interoperation For Lazy And Eager Evaluation, William Jeffrey Faught

Master's Theses

Programmers forgo existing solutions to problems in other programming lan- guages where software interoperation proves too cumbersome; they remake so- lutions, rather than reuse them. To facilitate reuse, interoperation must resolve language incompatibilities transparently. To address part of this problem, we present a model of computation that resolves incompatible lazy and eager eval- uation strategies using dual notions of evaluation contexts and values to mirror the lazy evaluation strategy in the eager one. This method could be extended to resolve incompatible evaluation strategies for any pair of languages with common expressions.

Investigation And Comparison Of Proportional Navigation Guidance And Beam Rider Guidance, Ertac Olgun

Electrical & Computer Engineering Theses & Dissertations

Air defense has an increasing importance in today's wars. To gain the advantage in air combat, pursuit interceptor aircraft, which use Air-to-Air Missiles (AAMs), have become more and more significant. However, these are not sufficient alone. The importance of Surface-to-Air Missiles (SAMs) also can not be ignored in air defense.

SAMs can use different tactical navigation guidance methods. Of these, two of the more important guidance methods are Proportional Navigation Guidance and Beam Rider Guidance, which are investigated in this thesis. To understand the idea better, a brief description and discussion of missiles are provided. Parts of the guided missiles …

Performance Analysis For Wimax Wireless Systems With Multiple Receive Antennas, Selcuk Taskin

Electrical & Computer Engineering Theses & Dissertations

Broadband wireless access has become the best way to meet the growing demand for fast Internet connections. WiMAX is one of the most promising broadband access technologies that allows fast deployment as well as low maintenance costs. WiMAX allows efficient use available bandwidth by using orthogonal frequency division multiplexing (OFDM) which is an efficient multi-carrier modulation technique. Diversity is a method for improving the reliability of a signal in fading environments by using two or more communication channels and is usually achieved by multiple antenna techniques.

In this thesis, receiver side diversity combining methods are studied and the performance of …

Modeling The Contagion Effect Of Foreclosures Within The Real Estate Market By Use Of Agent-Based Modeling And Simulation, Marshall William Gangel

Computational Modeling & Simulation Engineering Theses & Dissertations

Over the last several years, the US financial and real estate markets have experienced a significant recession. During this downturn, the number of real estate foreclosures rose drastically. Recent studies have empirically demonstrated a reduction in real estate values due to foreclosures. The observed reduction in the average value of real estate properties has been labeled the foreclosure contagion effect. The foreclosure contagion effect impacts healthy neighboring properties that surround the foreclosed property as a function of time and distance.

This study uses an agent-based modeling and simulation (ABMS} approach to explore the contagion effect of foreclosures. For this research, …

Electronic Warfare By Using Unmanned Aerial Vehicles, Aydin Meric

Electrical & Computer Engineering Theses & Dissertations

Technology continues to evolve rapidly by the day. Developments in technology should be followed closely if a country wants to become more powerful. Nowadays nobody can afford to ignore the importance of Electronic Warfare and Unmanned Aerial Vehicles (UAV) in military applications. Both of them play a crucial role in military operations that they can change the course of a war.

There are different kinds of Electronic Warfare methods that can be applied according to the situations and any evolving circumstances. In the beginning Electronic Warfare was used mainly for defensive purposes, but these days Electronic Warfare is used for …

Solving The Vehicle Re-Identification Problem By Using Neural Networks, Tanweer Rashid

Computational Modeling & Simulation Engineering Theses & Dissertations

Vehicle re-identification is the process by which vehicle attributes measured at one point on a road network are compared to vehicle attributes measured at another point in an effort to match vehicles without using any unique identifiers such as license plate numbers. A match is made if the two measurements are estimated to belong to the same vehicle. Vehicle attributes can be sensor readings such as loop induction signatures, or they can also be actual vehicle characteristics such as length, weight, number of axles, etc. This research makes use of vehicle length, travel time, axle spacing and axle weights for …

Unstructured Grid Technologies For Hydrodynamic Applications With Bodies In Relative Motion And Mesh Deformation, Lei Ji

Masters Theses and Doctoral Dissertations

Unstructured grid technologies for hydrodynamic applications with bodies in relative motion and mesh deformation are presented. A parallel universal mesh deformation scheme is developed to manage deforming surface and volume grids for both aerodynamic and hydrodynamic applications. The approach is universal and independent of grid type. Also, it requires minimal inter-processor communication and is thus perfectly suitable to a parallel platform. The original scheme of Allen (2006) has difficulty deforming volume grids in regions near concave geometry features and for abrupt grid resolution changes. Several modifications are proposed to overcome these problems. Grid quality can be improved significantly by adding …