Engineering Commons^™

Energy-Efficient Continuous Activity Recognition On Mobile Phones: An Activity-Adaptive Approach, Zhixian Yan, Vigneshwaran Subbaraju, Dipanjan Chakraborty, Archan Misra, Karl Aberer

Research Collection School Of Computing and Information Systems

Power consumption on mobile phones is a painful obstacle towards adoption of continuous sensing driven applications, e.g., continuously inferring individual’s locomotive activities (such as ‘sit’, ‘stand’ or ‘walk’) using the embedded accelerometer sensor. To reduce the energy overhead of such continuous activity sensing, we first investigate how the choice of accelerometer sampling frequency & classification features affects, separately for each activity, the “energy overhead” vs. “classification accuracy” tradeoff. We find that such tradeoff is activity specific. Based on this finding, we introduce an activity-sensitive strategy (dubbed “A3R” – Adaptive Accelerometer-based Activity Recognition) for continuous activity recognition, where the choice of …

Delayed Observation Planning In Partially Observable Domains, Pradeep Reddy Varakantham, Janusz Marecki

Research Collection School Of Computing and Information Systems

Traditional models for planning under uncertainty such as Markov Decision Processes (MDPs) or Partially Observable MDPs (POMDPs) assume that the observations about the results of agent actions are instantly available to the agent. In so doing, they are no longer applicable to domains where observations are received with delays caused by temporary unavailability of information (e.g. delayed response of the market to a new product). To that end, we make the following key contributions towards solving Delayed observation POMDPs (D-POMDPs): (i) We first provide an parameterized approximate algorithm for solving D-POMDPs efficiently, with desired accuracy; and (ii) We then propose …

Prioritized Shaping Of Models For Solving Dec-Pomdps, Pradeep Reddy Varakantham, William Yeoh, Prasanna Velagapudi, Paul Scerri

Research Collection School Of Computing and Information Systems

An interesting class of multi-agent POMDP planning problems can be solved by having agents iteratively solve individual POMDPs, find interactions with other individual plans, shape their transition and reward functions to encourage good interactions and discourage bad ones and then recompute a new plan. D-TREMOR showed that this approach can allow distributed planning for hundreds of agents. However, the quality and speed of the planning process depends on the prioritization scheme used. Lower priority agents shape their models with respect to the models of higher priority agents. In this paper, we introduce a new prioritization scheme that is guaranteed to …

Multipolymer Interactions In Bulk Heterojunction Photovoltaic Devices, Grant Olson

Physics

Multipolymer photovoltaics, single layer devices made up of multiple photoactive polymers, can create organic photovoltaics (OPVs) with a wider spectral response than single polymer systems without the difficult fabrication of a tandem. Our group has successfully created multipolymer solar devices with 2% power conversion efficiency. We have analyzed the optical and electrical properties of these devices, and found that it may be possible for polymers to assist each other with charge extraction, though combining polymers disrupts single polymer crystallinity.

The Hovering Ball Exhibit, Matthew Bauzon, Will Lennox, Michelle Swan

Mechanical Engineering

No abstract provided.

Quantifying Proximal Conformability Of A Thoracic Aortic Stent Graft, Dylan Reinsdorf, Kendall Smith

Mechanical Engineering

This report is documentation of a Senior Project completed by Dylan Reinsdorf and Kendall Smith, in partial fulfillment of a Bachelor of Science in Mechanical Engineering at Cal Poly, San Luis Obispo. Medtronic Inc. approached the team with a need to quantify proximal conformity of stent grafts in the thoracic aorta. A solution was designed that included an aorta model that simulates clinical conditions, and a measurement method for stent graft conformability. This report documents all phases of the project, from sponsor requirements to final design to product realization and testing.

Innovative Cargo Rack Solutions, Travis Mccart, Brian Blummer, Whit Ratcliff

Mechanical Engineering

This report describes the process of designing, building, and testing a lowering mechanism for a roof-mounted SUV cargo box. It provides a detailed problem description and a specific list of requirements that our design must comply with. Existing products and concepts are presented which meet one or more of our design requirements. Six design concepts are discussed and down-selected to three for further development. A final design has been chosen and described in detail. A team management plan is included to specify member responsibilities and a schedule details major deadlines and goals. Manufacturing processes and testing procedures are described in …

Design Of A Human Powered Helicopter Airframe, Sheen Kao, Daniel Layton, Philip Sobol

Mechanical Engineering

In 1989 Cal Poly’s Da Vinci III was the first human powered helicopter (HPH) to achieve flight; our goal is to research and develop a new airframe for the next generation Da Vinci. This report outlines a brief history of human powered flight and details a method of constructing for the airframe. An optimized airframe geometry was also researched and is explained in detail.

Formula Hybrid Drivetrain Design, Zachary (Zak) Mcfarland, Alex Pruitt, William Domhart

Mechanical Engineering

The Formula Hybrid senior project group was tasked with designing and building a drivetrain system for the Cal Poly Society of Automotive Engineers (SAE) Formula Hybrid (FHSAE) team. FHSAE gave customer requirements for performance and geometry for the drivetrain and the FHSAE rulebook has guidelines regarding safety requirements. The team chose to compete in the electric category of the 2012 FHSAE competition. After getting feedback from previous car performance and researching different powertrain options, the senior project team arrived at three conceptual ideas. Using a quality function deployment method, the senior project team chose the concept where two motors independently …

Throwing Frame For Athletes With Dissabilities, Andrew Higgins, Stefan Owechko, Gabriel (Gabe) Terrasas, Kevin Crisfield

Mechanical Engineering

Team Zeus’ senior project was to design, build and test a working throwing frame system for Bridge II Sports, a nonprofit organization in North Carolina. The throwing frame is used to allow athletes and individuals with disabilities to throw shot-put, discus, and javelin using a frame to sit against. Team Zeus was specifically tasked to build a frame that is lighter weight and more transportable than products that are currently on the market. This frame also is adjustable to accommodate a wide range of athlete weights, sizes, and abilities. The final result is a 35lb aluminum frame with two different …

Senior Project #7: Longboard Test Apparatus, Derek Chan, Colin Harris, Nico Lee

Mechanical Engineering

The aim of this project is to create a machine that will test longboards made by Method Sports and Freebord. Through analysis and many iterations, Board Busters has assembled a design to fulfill the requirements set forth by these companies, who also sponsor the project. Through use of a four-bar, frame, and two spinning disks, the machine will accurately simulate riding conditions seen by a board in use by customers, allowing the sponsoring companies to improve designs and verify warranties.

Recreational Nordic Sit Ski, Mathew Bissonnette, Johnathon Gorski, Kevin Izumiya

Mechanical Engineering

The purpose of this project was to design, build, and test a recreational Nordic sit ski for use by Disabled Sports Eastern Sierra. The goal was to improve adjustability and reduce weight compared to previous sit ski designs. The project was completed by Cal Poly Mechanical Engineering seniors Mathew Bissonnette, Johnathon Gorski, and Kevin Izumiya. Kinesiology seniors Harpreet Saini and Carl Anderson provided discipline support and disability etiquette training.

The project was sponsored by the National Science Foundation Research to Aid Persons with Disabilities (RAPD) grant. The grant was proposed by and awarded to Dr. Brian Self and Dr. James …

Thermocouple Calibration Device, Angelica M. Larios, Cameron D. Peck, Andrew J. Smith

Mechanical Engineering

The goal of this project is to develop a thermocouple calibration unit with a high degree of confidence and accuracy. This thermocouple calibration device will be designed and developed at Cal Poly San Luis Obispo and delivered to Tesla Motors Inc.

To best utilize thermocouples, they must be calibrated to a known accuracy. Non-commercially produced thermocouples have unknown accuracies. The final deliverable will be a semi-automated device that produces a calibration curve for each thermocouple with a known confidence and accuracy.

Creating A Solar Cell Array From A Single Silicon Wafer, Samyukta Gade, Roderick Marstell

Materials Engineering

Two different processes to create multi-celled solar panels from single wafers were made and implemented. To do this, the cells must not have a common ground, and both designs use different approaches to solve this problem. One utilizes a 2.9 µm deep n-type well within a 10.74 µm deep p-type well in an n-type wafer. There are two cells in series, which has a theoretical voltage of 1 V. The cells are connected in series with 1.9 µm thick gold traces. Any area that the gold is not in contact with the silicon has a .5 µm layer silicon dioxide …

The Effects Of Concentration, Stir Rate, And Processing Temperature On The Iridescence Of Polymethyl Methacrylate Nanoparticles, David Baruela

Materials Engineering

Synthetic opals were synthesized by creating polymethyl methacrylate (PMMA) nanospheres in order to determine which conditions would create the best iridescent samples. The factors affecting the iridescence were nanosphere concentration, stir rate, and processing temperature. PMMA solutions were made by adding 17 mg of granular azobis to a solution of 16 mL of distilled water with 3 mL of methyl methacrylate (MMA). The solution was stirred at different rates, slow and fast, and different temperatures, 70 °C and 90 °C, under a constant flow of nitrogen gas for 40 minutes until the polymerization reaction was complete. Glass substrates were prepared …

Fabricating Replacement Glass Prisms For The Piedras Blancas Lighthouse, Daniel Garcken

Materials Engineering

The objective of this project was to design and create a process for manufacturing replacement glass prisms for the Piedras Blancas lighthouse and several other lighthouses nationwide. The prisms were designed to be in multiple metal arrays spread across the floor of the beacon room (the topmost room of the lighthouses). The prisms functioned to transmit extra, radiant light from the beacon light through the floor of the beacon room and disperse it into the maintenance room below. Using computer aided drafting (CAD) software, an original prism was measured and modeled; the corresponding mold was also modeled. G-codes for controlling …

Effects Of Abrasive Particles On The Projected Fatigue Life Of Nylon Climbing Rope, Casey Johnson, Charlie Klonowski

Materials Engineering

When climbing rope is used outdoors, it is exposed to foreign particles such as sand and silt. These particles can potentially work their way through a rope’s sheath and damage the load bearing core decreasing the rope’s strength without exhibiting obvious wear. This project quantified the effect of abrasive particles on the fatigue life of nylon climbing rope. The experimental design involved 18 pieces of static nylon rope of kernmantle construction. 9 of these samples were heavy agitated in a slurry of water, silt, sand and soil, and left to sit for 24 hours. The remaining 9 samples were submerged …

Synthesis Of White Cadmium-Selenium Quantum Dots, Kyle Reilly

Materials Engineering

A process was developed for the synthesis of cadmium-selenium quantum dots that fluoresce at multiple wavelengths, giving a white color to the solution. The process involved making a selenium pre-cursor, then a cadmium precursor, then injecting the selenium precursor into the cadmium precursor and extracting a sample. Once the a repeatable process for synthesizing white quantum dots was developed, the absorption and fluorescence was measured and recorded over a period of two weeks. In the development of the process, the key variables were the temperature of the cadmium precursor and the time between injecting the selenium precursor and extracting the …

Characterization Of Positive Macrosegregation At The Subsurface Of Direct-Chill Cast 7050 Aluminum Forging Billets, Aaron Youril

Materials Engineering

Segregation of alloying elements during casting of forging billets may persist to the final forged component leading to unacceptable surface appearance. Determination of the elements or compounds that segregate is the essential first step to solving this problem. Differential Scanning Calorimetry (DSC) was used to determine a composition profile of the macrosegregation occurring at the subsurface of an as-cast 7050 aluminum alloy billet. Data collection was carried out by separating 10 to 20 mg samples from the outer centimeter along the radius of the billet, as well as samples from the bulk interior of the billet for comparison with the …

Analysis Of Failed Forging Saddling Mandrels And Process Improvements For Increased Mandrel Lifespan, Brock Costalupes

Materials Engineering

This project seeks to increase the lifespan of steel mandrels used by Schlosser Forge in the saddling process, which is part of the production of forged rings for the aerospace and power generation industries. All saddle mandrel samples were taken from used 4340 steel mandrels. Hardness profiles were measured across rectangular bars cut from the transverse direction of a completely fractured piece of a 7″ diameter mandrel. The hardness near one outer surface of the tested bar was 36 HRC and gradually decreased to 30.5 HRC at the opposite surface. Macroscopic examination of the primary fracture surface along with light …

Effect Of Heating Temperature, Heating Time And Initial Microstructure On Recrystallization Of Waspaloy During Heating For Forging, Marissa Hill

Materials Engineering

A fine, uniform grain size is required for creep limited Waspaloy in aircraft engine applications. Upon heating, Waspaloy does not always recrystallize in a uniform manner resulting in occasional large grains with a majority of the grains meeting the grain size requirements. Waspaloy’s microstructure was analyzed with different heat treatments and in the as-forged condition. The strengthening mechanism is the gamma prime phase. The gamma prime solvus temperature is 1908°F so the different heat treatments were determined around that temperature, as well as the forging temperature range of 1800-2150°F. At the 1850°F heat treatment, the microstructure recrystallized with small grains, …

Real World Computer Forensics, Jessica Riccio

Liberal Arts and Engineering Studies

No abstract provided.

A Guide To Producing An A Cappella Cd And Development Of A Pitch Detection Program, Jacob Ray Stringfellow

Liberal Arts and Engineering Studies

An in-depth look at the steps required to produce a CD for an a cappella group. From what microphone and preamplifiers to use, to what steps to take during the editing, mixing, and mastering processes. Finished with a look at pitch detection algorithms and how they work, and a little bit of experimentation with my own algorithm and program.

The Leading Contributor Of The Fukushima Daiichi Nuclear Power Plant Accident, Christopher Torres

Liberal Arts and Engineering Studies

No abstract provided.

Concurrent Byzantine Fault Tolerance For Software-Transactional-Memory Based Applications, Honglei Zhang, Wenbing Zhao

Electrical and Computer Engineering Faculty Publications

Typical Byzantine fault tolerance algorithms require the application requests to be executed sequentially, which may severely limit the throughput of the system considering that modern CPUs are equipped with multiple processing cores. In this paper, we present the design and implementation of a Byzantine fault tolerance framework for software-transactional-memory based applications that aims to maximize concurrent processing while preserving strong replica consistency. The approach is based on the idea of committing concurrent transactions according to the total order of the requests that triggered the transactions. A comprehensive performance evaluation is carried out to characterize the effectiveness and limitations of this …

Deviations In Standard Aggregate Gradation And Its Affects On The Properties Of Portland Cement Concrete, Marcus Balitsaris

All Theses

Aggregate gradation is the particle size distribution of both the stone and sand present in the concrete matrix. It is an aggregate property that has been heavily researched for over a century but the effects of which on concrete properties is still somewhat misunderstood. Past research has revealed that aggregate gradation dictates the proportion of aggregate to cement paste in concrete, and can play a major variable that determines the overall durability of the construction material. Increasingly, aggregate in South Carolina are failing to meet the standard aggregate gradation for portland cement concrete, however, the effects of such failed aggregate …

Me-Em Enewsbrief, June 2012, Department Of Mechanical Engineering-Engineering Mechanics, Michigan Technological University

Department of Mechanical and Aerospace Engineering eNewsBrief

No abstract provided.

An Experimental Investigation Of Glare And Restructured Fiber Metal Laminates, Adelina Vanessa Benedict

Doctoral Dissertations and Master's Theses

Fiber Metal Laminates (FMLs) are a group of materials fabricated by bonding glass/epoxy layers within metal layers. This class of materials can provide good mechanical properties, as well as weight savings. An FML known as Glass Laminate Aluminum Reinforced Epoxy (GLARE) was studied. An experimental investigation comprising of microscopy and tensile testing was carried out using different grades of GLARE. Microscopy revealed the construction details of GLARE, while tensile testing provided means of measuring and analyzing its stress-strain responses. Next, different metal surface pretreatment methods were explored. These included sandblasting, Phosphoric Acid Anodizing (PAA), and AC-130 Sol-Gel treatment. Woven S-2 …

Analysis Of The Impact Of Scenario-Based Training On The Aeronautical Decision Making Of Collegiate Flight Students, Mariko Genevieve Doskow

Doctoral Dissertations and Master's Theses

The persistence of faulty decision making as a primary cause of accidents indicates a need to train pilots to make better decisions. The purpose of this study was to analyze scenario-based training's effectiveness at improving the aeronautical decision making of collegiate flight students. The researcher scored each participant's aeronautical decision making as they completed simulated flights in an advanced aviation training device. The scores quantified the participants' aeronautical decision making on seven decision-making variables and served as the basis for generating an overall decision making score for each participant. The experimental group completed a scenario-based aeronautical decision making treatment between …

The Effect On Embry-Riddle Aeronautical University's Reporting Culture From Implementing An Aviation Safety Action Program, Robert Blake Kelly

Doctoral Dissertations and Master's Theses

The Flight Training Department at Embry-Riddle Aeronautical University, Daytona Beach, has been contemplating implementing an Aviation Safety Action Program (ASAP) in order to help protect students and instructors from certificate action. This feasibility study analyzed what motivated instructor pilots to submit safety reports, and if an ASAP would increase reporting from instructor pilots. It also identified what concerns existed among instructors and managers regarding an ASAP. A survey was given to instructors and managers; also instructors in leadership roles were interviewed. It was found that the benefit to the organization and peers was the highest motivation factor to submit safety …