Computer Engineering Commons^™

Ambient Habitat Noise And Vibration At The Georgia Aquarium, Peter M. Scheifele, Michael T. Johnson, Laura W. Kretschmer, John G. Clark, D. Kemper, G. Potty

Electrical and Computer Engineering Faculty Research and Publications

Underwater and in-air noise evaluations were completed in performance pool systems at Georgia Aquarium under normal operating conditions and with performance sound tracks playing. Ambient sound pressure levels at in-pool locations, with corresponding vibration measures from life support system (LSS) pumps, were measured in operating configurations, from shut down to full operation. Results indicate noise levels in the low frequency ranges below 100 Hz were the highest produced by the LSS relative to species hearing thresholds. The LSS had an acoustic impact of about 10 dB at frequencies up to 700 Hz, with a 20 dB re 1 μPa impact …

Energy Efficiency Analysis And Optimization On Mobile Video Wireless Delivery, Jianxin Sun

Department of Computer Electronics and Engineering: Dissertations, Theses, and Student Research

Micro-electronic industry has been boosting the capability of wireless mobile devices on full-scale. However, battery, as the only power source of most mobile devices, is experiencing a relatively slow development. Therefore, how to optimally utilize the limited battery energy on mobile devices under a predefined performance requirement becomes a critical issue. On the other hand, it is still unclear that how the battery capacity consumption is allocated on different working pattern of a specific video codec under various tempo-spatial scales and parameters, which has posed a design challenge on power management on multimedia communication system. Furthermore, an optimization method is …

Influence Of The Listening Context On The Perceived Realism Of Binaural Recordings, Davide Andrea Mauro, Francesco Vitale

Computer Sciences and Electrical Engineering Faculty Research

Binaural recordings and audio are becoming an interesting resource for composers, live performances and augmented reality. This paper focuses on the acceptance and the perceived quality by the audience of such spatial recordings. We present the results of a preliminary study of psychoacoustic perception where N=26 listeners had to report on the realism and the quality of different couples of sounds taken from two different rooms with peculiar reverb. Sounds are recorded with a self-made dummy head. The stimuli are grouped into classes with respects to some characteristics highlighted as potentially important for the task. Listening condition is fixed with …

Performance Optimization Over Wireless Links With Operating Constraints, Shiny Abraham

Electrical & Computer Engineering Theses & Dissertations

Wireless communication is one of the most active areas of technological innovations and groundbreaking research ranging from simple cellular phones to highly complex military monitoring devices. The emergence of radios with cognitive capabilities like software defined radios has revolutionized modern communication systems by providing transceivers which can vary their output waveforms as well as their demodulation methods. This adaptability plays a pivotal role in efficient utilization of radio spectrum in an intelligent way while simultaneously not interfering with other radio devices operating on the same frequency band. Thus, it is safe to say that current and future wireless systems and …

Multivariate Temporal Patterns Detection Using Reconstructed Phase Space And Gaussian Mixture Model In Dynamic Data System, Xin Feng, Wenjing Zhang

Electrical and Computer Engineering Faculty Research and Publications

No abstract provided.

Performance And Reliability Of Non-Markovian Heterogeneous Distributed Computing Systems, Jorge E. Pezoa, Majeed M. Hayat

Electrical and Computer Engineering Faculty Research and Publications

Average service time, quality-of-service (QoS), and service reliability associated with heterogeneous parallel and distributed computing systems (DCSs) are analytically characterized in a realistic setting for which tangible, stochastic communication delays are present with nonexponential distributions. The departure from the traditionally assumed exponential distributions for event times, such as task-execution times, communication arrival times and load-transfer delays, gives rise to a non-Markovian dynamical problem for which a novel age dependent, renewal-based distributed queuing model is developed. Numerical examples offered by the model shed light on the operational and system settings for which the Markovian setting, resulting from employing an exponential-distribution assumption …

Unconventional Uses Of Microcantilevers As Chemical Sensors In Gas And Liquid Media, I. Dufour, Fabien Josse, Stephen M. Heinrich, C. Lucat, C. Ayela, F. Ménil, O. Brand

Electrical and Computer Engineering Faculty Research and Publications

The use of microcantilevers as (bio)chemical sensors usually involves the application of a chemically sensitive layer. The coated device operates either in a static bending regime or in a dynamic flexural mode. While some of these coated devices may be operated successfully in both the static and the dynamic modes, others may suffer from certain shortcomings depending on the type of coating, the medium of operation and the sensing application. Such shortcomings include lack of selectivity and reversibility of the sensitive coating and a reduced quality factor due to the surrounding medium. In particular, the performance of microcantilevers excited in …

Identifying And Attributing Similar Traces With Greatest Common Factor Analysis, Fred Cohen

Journal of Digital Forensics, Security and Law

This paper presents an algorithm for comparing large numbers of traces to each other and identifying and presenting groups of traces with similar features. It is applied to forensic analysis in which groups of similar traces are automatically identified and presented so that attribution and other related claims may be asserted, and independently confirmed or refuted. The approach of this paper is to identify an approximate algorithm that will find a large subset of greatest common factor similar groups of arbitrary factors in far less time and space than an exact algorithm using examiner-provided selection criteria for factor definition.

A Wireless And Digital Electrode Bus Topology For Biopotential Measurement, Mark Nolan, Edward Burke, Eugene Coyle

Conference Papers

The conventional biopotential measurement configuration utilises long lead wires which connect measuring electrodes to signal conditioning circuitry. The majority of bioelectric signals that are measured from the human body have a tiny signal amplitude (5µV-5mV range) and thus any interference that is induced on the lead wires can have a detrimental effect on the original signal. In this paper, we present an alternative configuration, in which digitisation occurs on the electrode, potentially providing enhanced signal measurement as well as significant benefits in terms of the simplification of the physical interconnections between electrodes. Multiple electrodes are combined to form a digital …

Design And Simulation Of Interconnected H-Bridge Inverter, Samuel Muehleck

Computer Engineering

In this project, the research, design and simulation of an interconnected H-bridge single-phase inverter was explored. The inverter design was divided into three separate sections. First, a VHDL programmed CPLD was used to generate control signals for the transistors of the inverter circuit. Second, power electronics was used to create an inverter circuit to change a DC input to a 60 Hz AC output. Lastly, additional circuits were used to link the generated control signals to the MOSFET transistors of the inverter circuit. The operation of the three components was then validated with computer simulations. Results of computer simulation demonstrate …

Polygrasp: Reach; Myoelectric Prosthetic Hand Iteration, Devon Patrick Augustus, Mighells Blaed Deuel, Ian Noel Fraser, Nicholas Philip Moesser

Mechanical Engineering

Amputations are a common occurrence in soldiers returning home who have suffered the effects of IED and munitions explosions. For upper limb amputees, trans-radial amputations are the most common. Traditional hook devices do not offer an adequate level of normalcy for users, prompting the use of myoelectric devices. While current myoelectric devices do offer a more natural experience, they come with a host of other problems that makes their adoption by service personnel not desirable or not permitted by the VA. PolyGrasp Reach seeks to reduce weight and cost and improve performance. This addresses several of the issues with devices …

Iphone Breathalyzer: Point Oh Wait!, Gurpal Bhoot

Electrical Engineering

This final year project combines hardware and software components to create an alcohol breathalyzer that is compatible with the iPhone. The final design of the circuit and the iPhone application is original and combines multiple components to create the final product. Most of those components are seen in a simplified version of a breathalyzer, while the added components take care of the interface to the iPhone.

Frg Turbojet, Tyler Vitti

Computer Engineering

Members of the Cal Poly SLO campus club FRG work together with students of several different disciplines to build a functional turbojet engine. Engineering approaches include design, fabrication, testing, and computer sensing, control, and integration. The goal of the project is to produce a running turbojet engine monitored and controlled by embedded hardware and specialized PC software. This project is to be used by later groups for further research and development.

Reliable Software Updates For On-Orbit Cubesat Satellites, Sean Fitzsimmons

Master's Theses

CubeSat satellites have redefined the standard solution for conducting missions in space due to their unique form factor and cost. The harsh environment of space necessitates examining features that improve satellite robustness and ultimately extend lifetime, which is typical and vital for mission success. The CubeSat development team at Cal Poly, PolySat, has recently redefined its standard avionics platform to support more complex mission capabilities with this robustness in mind. A significant addition was the integration of the Linux operating system, which provides the flexibility to develop much more elaborate protection mechanisms within software, such as support for remote on-orbit …

Lyfi, Kianoosh Salami, Justin Cotton, Elush Shirazpour

Electrical Engineering

This paper will cover the steps necessary to design, build, and manage networkable smart light switches over WiFi via a mobile application. It contains a microcontroller running a real time operating system, a WiFi module, a Java server with SQLite databasing, and a mobile phone application.

LyFi is designed to turn on/off and dim household lights while only requiring the same installation procedure as a less capable dimmer switch. Once installed and connected to a network, LyFi will self-discover and configure. The server automatically propogates a database of nodes where any mobile device running an application can receive an updated …

Modeling And Parametric Design Of Permanent-Magnet Ac Machines Using Computationally Efficient Finite-Element Analysis, Gennadi Y. Sizov, Dan M. Ionel, Nabeel Demerdash

Electrical and Computer Engineering Faculty Research and Publications

Computationally efficient finite-element analysis (FEA) (CE-FEA) fully exploits the symmetries of electric and magnetic circuits of sine-wave current-regulated synchronous machines and yields substantial savings of computational efforts. Motor performance is evaluated through Fourier analysis and a minimum number of magnetostatic solutions. The major steady-state performance indices (average torque, ripple and cogging torque, back-electromotive-force waveforms, and core losses) are satisfactorily estimated as compared with the results of detailed time-stepping (transient) FEA. In this paper, the CE-FEA method is presented and applied to a parametric design study for an interior-permanent-magnet machine. Significant reduction of simulation times is achieved (approximately two orders of …

Wireless Medical Sensor Networks: Design Requirements And Enabling Technologies, Cecilia H. Vallejos De Schatz, Henry P. Medeiros, Fabio K. Schneider, Paulo J. Abatti

Electrical and Computer Engineering Faculty Research and Publications

This article analyzes wireless communication protocols that could be used in healthcare environments (e.g., hospitals and small clinics) to transfer real-time medical information obtained from noninvasive sensors. For this purpose the features of the three currently most widely used protocols—namely, Bluetooth^® (IEEE 802.15.1), ZigBee (IEEE 802.15.4), and Wi-Fi (IEEE 802.11)—are evaluated and compared. The important features under consideration include data bandwidth, frequency band, maximum transmission distance, encryption and authentication methods, power consumption, and current applications. In addition, an overview of network requirements with respect to medical sensor features, patient safety and patient data privacy, quality of service, and interoperability …

Using Inductance As A Tuning Parameter For Rf Meta-Atoms, Derrick Langley, Ronald A. Coutu Jr., Peter J. Collins

Electrical and Computer Engineering Faculty Research and Publications

The resonant frequency of metamaterials structured with split ring resonator (SRR) meta-atoms is determined primarily through the capacitance and inductance of the individual meta-atoms. Two designs that vary inductance incrementally were modeled, simulated, fabricated, and tested to investigate the role inductance plays in metamaterial designs. The designs consisted of strategically adding sections to the SRR to increase the inductance, but in a manner that minimized capacitance variations. Each design showed a shift in resonant frequency that was proportional to the length of the added section. As the length of each section was increased, the resonant frequency shifted from 2.78 GHz …

Fault-Tolerant Operation Of Delta-Connected Scalar- And Vector-Controlled Ac Motor Drives, Ahmed Mohamed Sayed Ahmed, Nabeel Demerdash

Electrical and Computer Engineering Faculty Research and Publications

Operation and analysis of delta-connected ac motor-drive systems under fault-tolerant open-phase mode of operation is introduced in this paper for both scalar- and vector-controlled motor-drive systems. This technique enables the operation of the three-phase motor upon a failure in one of its phases without the need of a special fault-detection algorithm. It is mainly used to significantly mitigate torque pulsations, which are caused by an open-delta configuration in the stator windings. The performance of the fault-tolerant system was verified using a detailed time stepping finite element simulation as well experimental tests for a 5-hp 460-V induction motor-drive system and the …

Digital Evidence Education In Schools Of Law, Aaron Alva, Barbara Endicott-Popovsky

Annual ADFSL Conference on Digital Forensics, Security and Law

An examination of State of Connecticut v. Julie Amero provides insight into how a general lack of understanding of digital evidence can cause an innocent defendant to be wrongfully convicted. By contrast, the 101-page opinion in Lorraine v. Markel American Insurance Co. provides legal precedence and a detailed consideration for the admission of digital evidence. An analysis of both cases leads the authors to recommend additions to Law School curricula designed to raise the awareness of the legal community to ensure such travesties of justice, as in the Amero case, don’t occur in the future. Work underway at the University …

A Case Study Of The Challenges Of Cyber Forensics Analysis Of Digital Evidence In A Child Pornography Trial, Richard Boddington

Annual ADFSL Conference on Digital Forensics, Security and Law

Perfunctory case analysis, lack of evidence validation, and an inability or unwillingness to present understandable analysis reports adversely affect the outcome course of legal trials reliant on digital evidence. These issues have serious consequences for defendants facing heavy penalties or imprisonment yet expect their defence counsel to have clear understanding of the evidence. Poorly reasoned, validated and presented digital evidence can result in conviction of the innocent as well as acquittal of the guilty. A possession of child pornography Case Study highlights the issues that appear to plague case analysis and presentation of digital evidence relied on in these odious …

After Five Years Of E-Discovery Missteps: Sanctions Or Safe Harbor?, Milton Luoma, Vicki Luoma

Annual ADFSL Conference on Digital Forensics, Security and Law

In 2003 the Zubulake case became the catalyst of change in the world of e-discovery. In that case Judge Shira Scheindlin of the United States District Court for the Southern District of New York set guidelines for e-discovery that served as the basis for amending the Federal Rules of Civil Procedure (FRCP) in December 2006. The amendments incorporated a number of concepts that were described by Judge Scheindlin in the Zubulake case. ( Zubulake v. UBS Warburg LLC, 2003) Since the Zubulake case and the FRCP amendments, numerous cases have interpreted these rules changes, but one of the main points …

Multi-Parameter Sensitivity Analysis Of A Bayesian Network From A Digital Forensic Investigation, Richard E. Overill, Echo P. Zhang, Kam-Pui Chow

Annual ADFSL Conference on Digital Forensics, Security and Law

A multi-parameter sensitivity analysis of a Bayesian network (BN) used in the digital forensic investigation of the Yahoo! email case has been performed using the principle of ‘steepest gradient’ in the parameter space of the conditional probabilities. This procedure delivers a more reliable result for the dependence of the posterior probability of the BN on the values used to populate the conditional probability tables (CPTs) of the BN. As such, this work extends our previous studies using singleparameter sensitivity analyses of BNs, with the overall aim of more deeply understanding the indicative use of BNs within the digital forensic and …

Facilitating Forensics In The Mobile Millennium Through Proactive Enterprise Security, Andrew R. Scholnick

Annual ADFSL Conference on Digital Forensics, Security and Law

This work explores the impact of the emerging mobile communication device paradigm on the security-conscious enterprise, with regard to providing insights for proactive Information Assurance and facilitation of eventual Forensic analysis. Attention is given to technology evolution in the areas of best practices, attack vectors, software and hardware performance, access and activity monitoring, and architectural models.

Keywords: Forensics, enterprise security, mobile communication, best practices, attack vectors.

Cloud Forensics Investigation: Tracing Infringing Sharing Of Copyrighted Content In Cloud, Yi-Jun He, Echo P. Zhang, Lucas C.K. Hui, Siu Ming Yiu, K.P. Chow

Annual ADFSL Conference on Digital Forensics, Security and Law

Cloud Computing is becoming a significant technology trend nowadays, but its abrupt rise also creates a brand new front for cybercrime investigation with various challenges. One of the challenges is to track down infringing sharing of copyrighted content in cloud. To solve this problem, we study a typical type of content sharing technologies in cloud computing, analyze the challenges that the new technologies bring to forensics, formalize a procedure to get digital evidences and obtain analytical results based on the evidences to track down illegal uploader. Furthermore, we propose a reasoning model based on the probability distribution in a Bayesian …

Ipad2 Logical Acquisition: Automated Or Manual Examination?, Somaya Ali, Sumaya Alhosani, Farah Alzarooni, Ibrahim Baggili

Annual ADFSL Conference on Digital Forensics, Security and Law

Due to their usage increase worldwide, iPads are on the path of becoming key sources of digital evidence in criminal investigations. This research investigated the logical backup acquisition and examination of the iPad2 device using the Apple iTunes backup utility while manually examining the backup data (manual examination) and automatically parsing the backup data (Lantern software - automated examination). The results indicate that a manual examination of the logical backup structure from iTunes reveals more digital evidence, especially if installed application data is required for an investigation. However, the researchers note that if a quick triage is needed of an …

A Fuzzy Hashing Approach Based On Random Sequences And Hamming Distance, Frank Breitinger, Harald Baier

Annual ADFSL Conference on Digital Forensics, Security and Law

Hash functions are well-known methods in computer science to map arbitrary large input to bit strings of a fixed length that serve as unique input identifier/fingerprints. A key property of cryptographic hash functions is that even if only one bit of the input is changed the output behaves pseudo randomly and therefore similar files cannot be identified. However, in the area of computer forensics it is also necessary to find similar files (e.g. different versions of a file), wherefore we need a similarity preserving hash function also called fuzzy hash function. In this paper we present a new approach for …

The Xbox 360 And Steganography: How Criminals And Terrorists Could Be "Going Dark", Ashley Podhradsky, Rob D’Ovidio, Cindy Casey

Annual ADFSL Conference on Digital Forensics, Security and Law

Video game consoles have evolved from single-player embedded systems with rudimentary processing and graphics capabilities to multipurpose devices that provide users with parallel functionality to contemporary desktop and laptop computers. Besides offering video games with rich graphics and multiuser network play, today's gaming consoles give users the ability to communicate via email, video and text chat; transfer pictures, videos, and file;, and surf the World-Wide-Web. These communication capabilities have, unfortunately, been exploited by people to plan and commit a variety of criminal activities. In an attempt to cover the digital tracks of these unlawful undertakings, anti-forensic techniques, such as steganography, …

Double-Compressed Jpeg Detection In A Steganalysis System, Jennifer L. Davidson, Pooja Parajape

Annual ADFSL Conference on Digital Forensics, Security and Law

The detection of hidden messages in JPEG images is a growing concern. Current detection of JPEG stego images must include detection of double compression: a JPEG image is double compressed if it has been compressed with one quality factor, uncompressed, and then re-compressed with a different quality factor. When detection of double compression is not included, erroneous detection rates are very high. The main contribution of this paper is to present an efficient double-compression detection algorithm that has relatively lower dimensionality of features and relatively lower computational time for the detection part, than current comparative classifiers. We use a model-based …

Toward Alignment Between Communities Of Practice And Knowledge-Based Decision Support, Jason Nichols, David Biros, Mark Weiser

Annual ADFSL Conference on Digital Forensics, Security and Law

The National Repository of Digital Forensics Information (NRDFI) is a knowledge repository for law enforcement digital forensics investigators (LEDFI). Over six years, the NRDFI has undertaken significant design revisions in order to more closely align the architecture of the system with theory addressing motivation to share knowledge and communication within ego-centric groups and communities of practice. These revisions have been met with minimal change in usage patterns by LEDFI community members, calling into question the applicability of relevant theory when the domain for knowledge sharing activities expands beyond the confines of an individual organization to a community of practice. When …