Engineering Commons^™

Sugarcane Bagasse As A Carrier For The Immobilization Of Saccharomyces Cerevisiaein Bioethanol Production, Sita Heris Anita, Wibowo Mangunwardoyo, Yopi Yopi

Makara Journal of Technology

Sugarcane bagasse was used as a carrier to immobilize Saccharomyces cerevisiae in bioethanol production. This research aims to study the potential use of sugarcane bagasse as an alternative carrier for cell immobilization and improvement in the production process of cell immobilization in bagasse. The results showed that the physical characteristics of sugarcane bagasse as a carrier were water content (7.77 ± 0.35%), water retention (4.80 ± 0.44 g/g), water absorption index (8.58 ± 0.22 g/g), and lignin content (24.40 ± 1.52 %). Determination of cell retention was performed in an inoculum volume of 50 mL yeast suspension with various carrier …

Osem : Occupant-Specific Energy Monitoring., Anand S. Kulkarni

Electronic Theses and Dissertations

Electricity has become prevalent in modern day lives. Almost all the comforts people enjoy today, like home heating and cooling, indoor and outdoor lighting, computers, home and office appliances, depend on electricity. Moreover, the demand for electricity is increasing across the globe. The increasing demand for electricity and the increased awareness about carbon footprints have raised interest in the implementation of energy efficiency measures. A feasible remedy to conserve energy is to provide energy consumption feedback. This approach has suggested the possibility of considerable reduction in the energy consumption, which is in the range of 3.8% to 12%. Currently, research …

A System For Monitoring And Managing Indoor Air Quality And Environmental Conditions, Ali Ibrahim

Boise State University Theses and Dissertations

The quality of indoor air depends on different types of pollutant sources existing in a semi-enclosed environment. The sources can be biological, chemical, or toxic pollutants. These sources can cause health issues and discomfort for occupants. One of the indicators of poor indoor air quality is Carbon Dioxide (CO₂). CO₂ can be used to indicate the indoor air exchange rate. The lack of air exchange means higher levels of CO₂. High levels of indoor particulates can also be an indication of poor air quality. Due to the lack of fresh air, air circulation, and air …

Channel Estimation Overhead Reduction For Downlink Fdd Massive Mimo Systems, Abderrahmane Mayouche

Graduate Theses and Dissertations

Massive multiple-input multiple-output (MIMO) is the concept of deploying a very large number of antennas at the base stations (BS) of cellular networks. Frequency-division duplexing (FDD) massive MIMO systems in the downlink (DL) suffer significantly from the channel estimation overhead. In this thesis, we propose a minimum mean square error (MMSE)-based channel estimation framework that exploits the spatial correlation between the antennas at the BS to reduce the latter overhead. We investigate how the number of antennas at the BS affects the channel estimation error through analytical and asymptotic analysis. In addition, we derive a lower bound on the spectral …

Loss Model For Gallium Nitride Dc-Dc Buck Converter, Rushi Patel, Daniel Costinett

BCoE Publications

In recent years, more research has been done on Enhancement Mode Gallium Nitride (eGaN) converters as the world is moving towards more power efficient converters. The process to make converters more efficient was complicated and slow in the twentieth century. With help of simulation tools such as MATLAB and LTspice, this process has become much faster and reliable in the modern era. In order to make this process even faster, one of the important aspects in power electronics is to evaluate different losses in the converter. A model for estimating power losses for eGaN DC-DC buck converter (12V/1.2V) is illustrated …

Development Of Two Pdci Damping Controller Supervisory Elements, James Colwell

Graduate Theses & Non-Theses

Long transmission lines create opportunities for synchronous generators to oscillate or swing against one another at frequencies known as inter-area modes that are well observed. Some modes become less damped during times of heavy loading on the power system. Due to these modes, transmission systems are generally constrained by dynamic limits. Approaches to improve system damping are being researched. One method being evaluated is modulating power flows on the Pacific Direct Current Intertie (PDCI). A derivative feedback control system using phasor measurement unit (PMU) data has been shown in simulation to improve system damping. However, any feedback control scheme utilized …

Analysis Of Various Classification Techniques For Computer Aided Detection System Of Pulmonary Nodules In Ct, Barath Narayanan Narayanan, Russell C. Hardie, Temesguen Messay

Electrical and Computer Engineering Faculty Publications

Lung cancer is the leading cause of cancer death in the United States. It usually exhibits its presence with the formation of pulmonary nodules. Nodules are round or oval-shaped growth present in the lung. Computed Tomography (CT) scans are used by radiologists to detect such nodules. Computer Aided Detection (CAD) of such nodules would aid in providing a second opinion to the radiologists and would be of valuable help in lung cancer screening. In this research, we study various feature selection methods for the CAD system framework proposed in FlyerScan. Algorithmic steps of FlyerScan include (i) local contrast enhancement (ii) …

Simulation, Measurement, And Emulation Of Photovoltaic Modules Using High Frequency And High Power Density Power Electronic Circuits, Yunas Erkaya

Electrical & Computer Engineering Theses & Dissertations

The number of solar photovoltaic (PV) installations is growing exponentially, and to improve the energy yield and the efficiency of PV systems, it is necessary to have correct methods for simulation, measurement, and emulation. PV systems can be simulated using PV models for different configurations and technologies of PV modules. Additionally, different environmental conditions of solar irradiance, temperature, and partial shading can be incorporated in the model to accurately simulate PV systems for any given condition.

The electrical measurement of PV systems both prior to and after making electrical connections is important for attaining high efficiency and reliability. Measuring PV …

Benefits Of Considering More Than Temperature Acceleration For Gan Hemt Life Testing, Ronald A. Coutu Jr., Robert A. Lake, Bradley D. Christiansen, Eric R. Heller, Christopher A. Bozada, Brian S. Poling, Glen D. Via, James P. Theimer, Stephen E. Tetlak, Ramakrishna Vetury, Jeffrey B. Shealy

Faculty Publications

The purpose of this work was to investigate the validity of Arrhenius accelerated-life testing when applied to gallium nitride (GaN) high electron mobility transistors (HEMT) lifetime assessments, where the standard assumption is that only critical stressor is temperature, which is derived from operating power, device channel-case, thermal resistance, and baseplate temperature. We found that power or temperature alone could not explain difference in observed degradation, and that accelerated life tests employed by industry can benefit by considering the impact of accelerating factors besides temperature. Specifically, we found that the voltage used to reach a desired power dissipation is important, and …

The Design, Fabrication And Characterization Of Integrated Photoconductive Antennas For On-Chip Terahertz Wave Radiation And Detection, Ruben Dario Velasquez Rios

Dissertations, Theses, and Capstone Projects

Terahertz (THz) wave (between 0.1 and 10 THz) is attracting a lot of attention due to its unique properties that are favorable to various applications. These include non-ionizing radiation, better resolution than a microwave, unique spectral absorption, and an ability to propagate through many types of materials. It has been intensively researched in sensing and imaging technology for a wide range of applications in areas such as biology, pharmaceutical, food and drug control, medical science, and security screening. Driven by mostly scientific research interests, the majority of THz systems are more focused on system performance rather than system size, integration, …

Cal Poly Supermileage Electronic Fuel Injection, Alexander Pink

Electrical Engineering

Cal Poly Supermileage is a student-run engineering club that builds prototype gasoline vehicles optimized maximum fuel-efficiency. To power their vehicles, the Supermileage team makes use of single-cylinder, 4-stroke, electronically fuel-injected (EFI) gasoline engines. This report details the development, iterative design & test cycles, and integration of an EFI system for the Supermileage club. This project develops an EFI system that interfaces to the most common types of sensors found in the low-power Supermileage-range of engines, including throttle-position sensors, manifold absolute pressure sensors, gear-tooth hall-effect sensors, variable-reluctance position sensors, engine coolant temperature sensors, intake air temperature sensors, and exhaust oxygen sensors. …

Camera Stabilizer, Nathaniel Bryan, Sean Chappell, Danielle Williams

Electrical Engineering

The goal of this project is to create an affordable camera stabilizer (the “stabilizer”) for consumers to use with cell phones or GoPro cameras. The stabilizer compensates for two axes, pitch and roll, as well as vertical movement. The system (currently only compatible with one cell phone model) is handheld and uses a combination of brushless DC motors, an Inertial Measurement Unit (IMU), and a microcontroller to compensate for the operator’s movements, stabilizing the phone for nonshaky, high quality video recording. The stabilizer provides a lowcost alternative to professional stabilization solutions employed in the production of featurelength films; the system …

Exertion Control, Travis Taylor

Electrical Engineering

Current wearable fitness devices give the user after-the-fact fitness data, but little real-time feedback. Exertion Control, a new wearable device, continuously measures the user’s heart rate, creates a heart rate target, and helps the user reach it. This project completes the senior design and master’s thesis requirements and contains two milestones. The senior design product continuously measures the wearer’s heart rate and logs it with a user-friendly interface. This data models the heart’s exertion response and recovery response. The master’s thesis device refines the closed control loop with the user to give them a workout optimized to fit their needs.

Robotic Overbed Table, Jonathan Lantz

Electrical Engineering

Traditionally overbed tables have simple and cheap designs, yet contain many disadvantages compared to the design proposed in this report. Disabled or bedridden persons, often require the use of a bedside table either in hospital environments or at home. Unfortunately, many modern overbed tables require the user to get out of bed and move in order to adjust and position the table. Incorporating a singlebutton control panel that allows the user to make adjustments and access other features independently, creates more accessible product. Integrated subsystems must control all motors and interfaces with an easy access control panel in order to …

El Capitán: Cal Poly Rose Float Digital Drive System, Gregory Raffi Baghdikian

Computer Engineering

In today’s world of smartphones, self-driving cars, and internet-connected coffee makers, it seems as if computers are contained in everything around us. These “embedded systems” have become critical components of our lives, improving everything about the things they control, from cost, to speed, to simplicity. One area that embedded systems has hardly gained a foothold is in the world of floatbuilding. Most of the floats in the Tournament of Roses Parade, including the one built jointly by Cal Poly San Luis Obispo and Cal Poly Pomona, are technologically very simple, using mostly analog components and rudimentary discrete digital logic to …

Musictrakr, Benjamin Lin

Computer Engineering

MusicTrackr is an IoT device that musicians attach to their instruments. The device has a start and stop button that allows users to record their playing sessions. Each recorded session is sent wirelessly to a cloud database. An accompanying website displays all of the recorded sessions, organized by date. After picking a specific date, the user can view graphs showing total practice time and average session length as well play back any recordings during that date. In addition, the user may add comments to any specific date or recording. Lastly, the user may tag a specific date with a color …

Complex Filters As As A Cascade Of Of Buffered Gingell Structures: Design From From Band-Stop Constraints, Samuel Robert Johnston

Master's Theses

This thesis presents an active Complex Filter implementation that that creates a transfer function with with a single real pole and a complex zero. The two-input/two-output network developed in in this thesis responds differently based upon upon the relative phase difference of of the two inputs. If a negative ninety-degree phase difference occurs between the two inputs, the filter will exhibits a bandstop response. While a positive ninety-degree phase difference exhibits a bandpass response. This topology is relatesd to to Gingell’s RC-CR polyphase topology but because of of the use of of op-amps, can be cascadedd without without suffering loading …

Testing Feasibility Of Inductive Power Coupling For Modern Applications, Andrew Burman

BioResource and Agricultural Engineering

This project takes two bifilar tesla coils and uses them to find a % efficiency of power transfer as distances between the coils decrease. The reason this experiment is being conducted is to find possible implications for wireless charging of vehicles using similar style coils. This project conducted experiments on 60 Hz, 400 Hz, and 1 kHz frequencies for a small input signal. The general conclusion is that as the frequency increases more power can be transferred and higher efficiency of power transfer is seen. This project also concluded that it could be possible to get higher efficiency at a …

Design And Implementation Of A Three Dimensional Printer Using A Cylindrical Printing Process, Brandon Hoy

Electrical Engineering

Many 3D printers utilize a Cartesian (XYZ) printing process. Implementing a polar coordinate printer providing a faster printing method and introduces new printing algorithms, increasing printing efficiency. This cylindrical 3D printer applies a circular-moving baseplate and a heating printer head (extruder) moving radially and vertically. A processor accepts pre-processed polar data points and transpose the appropriate programmed printing commands to the motors units. The extruder also has a control loop, keeping the temperature inside the desired range. This prototype prints using polylactic acid (PLA) filament. Additionally, a display screen updates every second the: printing time, extruder temperature, and status notifications.

Rapid Battery Exchange (Rbx), Daniel Rostom

Electrical Engineering

Electric vehicles have begun to hit the main stream market, with sales raising form under 20,000 in 2001 to over 110,000 per year since 2014 [1]. With new models hitting the market every year, and more people becoming conscious about their fossil fuel usage, this trend will only continue until there are more electric vehicles than combustion vehicles on the road. A major drawback of electric vehicles is their limited range, and relatively long recharge times. Even with advancements in battery charging speed, such as the Tesla super charger, able to provide up to 90 miles of range in just …

Active Charge Balancing For Cardiac Stimulation, Maci Miri

Electrical Engineering

Worldwide, there are about 3 million people who have pacemakers, with 10,000 new implantations of ICD’s each month. [heart.org] Due to the gravity and importance of the function that ICD’s provide, these devices must be extremely reliable and highly effective. However, because of the high tolerances of IC manufacturing, stimulation circuits for pacemakers may be slightly unmatched and over time, may have a net DC charge applied to the tissues in the heart. Extra charge pumped into body tissues is dangerous for the patient’s health; the pH of the tissue can be raised and corrosion of the stimulating electrodes may …

A Stroke Therapy Brace Design, Evan Kirkbride

Electrical Engineering

Victims of stroke often have difficulty with rehabilitation. With limited movement on their affected arm, patients often do not want to move much for physical therapy. In this project, we design a robotic brace that helps stroke patients move their arm more effectively in a reaching or pulling motion. By giving patients more movement in their affected arm than they would have otherwise, patients gain more from rehabilitation. The brace also adapts to the patient’s needs, providing more inclination or resistance as needed for their physical therapy. This kind of therapy engages patients rather than relying on their likely dwindled …

Car Safe, David Van Workum

Electrical Engineering

The Car Safe project helps protect parents and caretakers from the dangers associated with leaving children in hot vehicles. The device supports parents through notifying them of the child’s wellbeing and status while within an automobile. Specifically, the device monitors the child’s ergonomic experience and the spatial proximity between the caretaker and child. Car Safe utilizes this information and determines if the child finds himself in a dangerous environment. Due to its compact design, the device functions independently of a specific car seat design, allowing customers to integrate Car Safe in the car seat environment of their choosing.

Design Of An Integrated Acceleration Acquisition Subsystem To Satisfy High-Speed And Low-Area Requirements For Cubesats, Ryan J. Rumsey

Master's Theses

Cal Poly San Luis Obispo’s PolySat team is designing the Multipurpose Orbital Spring Ejection System (MOSES) in order to record acceleration data during the launch of CubeSats as well as to provide GPS coordinates to locate the position of CubeSats once they are injected into orbit. This work focuses on the design and development of the acceleration data acquisition (DAQ) subsystem of MOSES. This subsystem is designed around the need for a high-speed sampling system of at least 200 kHz across four channels of data, plus low-area limitations in the MOSES form factor which is roughly half the size of …

Bitrate Classification Of Twice-Encoded Audio Using Objective Quality Features, Colm Sloan, Damien Kelly, Naomi Harte, Anil C. Kokaram, Andrew Hines

Conference papers

When a user uploads audio files to a music stream- ing service, these files are subsequently re-encoded to lower bitrates to target different devices, e.g. low bitrate for mobile. To save time and bandwidth uploading files, some users encode their original files using a lossy codec. The metadata for these files cannot always be trusted as users might have encoded their files more than once. Determining the lowest bitrate of the files allows the streaming service to skip the process of encoding the files to bitrates higher than that of the uploaded files, saving on processing and storage space. This …

Manufacturing And Characterization Of Poly (Lactic Acid)/Carbon Black Conductive Composites For Fdm Feedstock: An Exploratory Study, Dylan Fitz-Gerald, Justin Boothe

Materials Engineering

This exploratory study developed methods of manufacturing and characterizing the electrical properties of small batches of conductive composite feedstock for the Fused Deposition Modeling (FDM) manufacturing process, commonly known as 3D printing. We utilized a solution casting process of Poly(lactic acid) (PLA) (Grade 4043D, NatureWorks, LLC.) and Carbon Black (CB) (Vulcan® XC72, Cabot Corp.) in chloroform. The resulting composite precursor was cryogenically treated with liquid nitrogen and milled in a coffee grinder in order to achieve particles that could be fed into the extruder. Composite precursors were dried in a vacuum oven at an elevated temperature of 38°C. Filaments were …

Design Of Inexpensive And Easy To Use Diy Internet Of Things Platform, Samuel R. Jaffe

Master's Theses

This thesis focuses on the design and implementation of a new, inexpensive, and less complex system for a Do-It-Yourself (DIY) Internet of Things (IoT) platform. The hardware aspects focus on a new chip called the ESP8266 which contains both microcontroller and WiFi connectivity capabilities in an extremely affordable package. The system uses the Arduino IDE to program the ESP8266, which is known to be an extremely user-friendly environment. All other software is both free and easy to use. Past methods of creating IoT projects involved either expensive hardware, often ranging from $50-$100 per node, or complicated programming requiring a full …

Low-Frequency Series Loaded Resonant Inverter Characterization, Alfredo Medina

Master's Theses

Modern power systems require multiple conversions between DC and AC to deliver power from renewable energy sources. Recent growth in DC loads result in increased system costs and reduced efficiency, due to redundant conversions. Advances in DC microgrid systems demonstrate superior performance by reducing conversion stages. The literature reveals practical DC microgrid systems composed of wind and solar power to replace existing fossil fuel technologies for residential consumers. Although higher efficiencies are achieved, some household appliances require AC power; thus, the need for highly efficient DC to AC converters is imperative in establishing DC microgrid systems. Resonant inverter topologies exhibit …

Hall Effect Modeling In Fem Simulators And Comparison To Experimental Results In Silicon And Printed Sensors, Leonardo A. Frem

Master's Theses

Finite element method simulation models for thin-film semiconductor-based Hall sensors were developed using secondary data in order to understand their behavior under strong magnetic fields. Given a device geometry and charge carrier density and mobility, the models accurately calculated sensor resistance, Hall voltage under a normally-incident constant magnetic field, and expected offset from a population of Hall devices. The model was successfully matched against data from integrated chip Hall sensors from St. Jude Medical. Additionally, the feasibility of creating Hall effect devices with common carbon ink was explored experimentally. The material properties obtained from testing these ink-based devices through the …

Vector Processor Virtualization: Distributed Memory Hierarchy And Simultaneous Multithreading, Seyedamin Rooholamin

Dissertations

Taking advantage of DLP (Data-Level Parallelism) is indispensable in most data streaming and multimedia applications. Several architectures have been proposed to improve both the performance and energy consumption for such applications. Superscalar and VLIW (Very Long Instruction Word) processors, along with SIMD (Single-Instruction Multiple-Data) and vector processor (VP) accelerators, are among the available options for designers to accomplish their desired requirements. On the other hand, these choices turn out to be large resource and energy consumers, while also not being always used efficiently due to data dependencies among instructions and limited portion of vectorizable code in single applications that deploy …