Engineering Commons^™

Effects Of Su-8 Cross-Linking On Flip-Chip Bond Strength When Assembling And Packaging Mems, Nathan E. Glavitz, Lavern A. Starman, Ronald A. Coutu Jr., Richard L. Johnson

Electrical and Computer Engineering Faculty Research and Publications

New methods to assemble, integrate, and package micro devices are always needed in attempts to simplify and expedite fabrication methods to maximize throughput. Our paper focuses on assessing SU-8 as a viable material for packaging and flip chip bonding processes for MEMS and micro devices. In this paper, we vary the level of cross- linking through post exposure bake (PEB) times and assess rectangular ring test structures bonding strength following flip chip bonding through applied tensile loads. In addition, we performed initial assessments on the etching resiliency of varied cross-linking of SU-8. From initial results, the bonding strength is maximized …

Data Compressive Paradigm For Multispectral Sensing Using Tunable Dwell Mid-Infrared Detectors, Woo-Yong Jang, Majeed M. Hayat, Sebastian E. Godoy, Steven C. Bender, Payman Zarkesh-Ha, Sanjay Krishna

Electrical and Computer Engineering Faculty Research and Publications

While quantum dots-in-a-well (DWELL) infrared photodetectors have the feature that their spectral responses can be shifted continuously by varying the applied bias, the width of the spectral response at any applied bias is not sufficiently narrow for use in multispectral sensing without the aid of spectral filters. To achieve higher spectral resolutions without using physical spectral filters, algorithms have been developed for post-processing the DWELL’s bias-dependent photocurrents resulting from probing an object of interest repeatedly over a wide range of applied biases. At the heart of these algorithms is the ability to approximate an arbitrary spectral filter, which we desire …

Application Of Spatial Bandwidth Concepts To Mas Pole Location For Dielectric Cylinders, James Richie

Electrical and Computer Engineering Faculty Research and Publications

The concept of effective spatial bandwidth (EBW) is extended from the case of an MAS solution for perfectly conducting (PEC) cylinders to dielectric cylinders. It is shown that the ideas and results for the conducting cylinder apply in a straightforward manner to the dielectric case. For the dielectric case, there are two auxiliary surfaces. Because the EBW calculations are independent of the scatterer material, the auxiliary surface for the scattered field will follow the same guidelines for both the PEC and dielectric cases. The guidelines for the second auxiliary surface are described and verified here. Guidelines for both a plane …

6.4 Ghz Acoustic Sensor For In-Situ Monitoring Of Afm Tip Wear, T.J. Cheng, Jun Hyun Han, Michael Ziwisky, Chung-Hoon Lee, S.A. Bhave

Electrical and Computer Engineering Faculty Research and Publications

This paper demonstrates an acoustic sensor that can resolve atomic force microscopy (AFM) tip blunting with a frequency sensitivity of 0.007%. The AFM tip is fabricated on a thin film piezoelectric aluminum nitride (AlN) membrane that is excited as a film bulk acoustic resonator (FBAR). We demonstrate that cutting 0.98 μm off of the tip apex results in a resonance frequency change of 0.4MHz at 6.387GHz. This work demonstrates the potential for in-situ monitoring of AFM tip wear.

On The Applications Of Deterministic Chaos For Encrypting Data On The Cloud, Jonathan Blackledge, Nikolai Ptitsyn

Conference papers

Cloud computing is expected to grow considerably in the future because it has so many advantages with regard to sale and cost, change management, next generation architectures, choice and agility. However, one of the principal concerns for users of the Cloud is lack of control and above all, data security. This paper considers an approach to encrypting information before it is ‘placed’ on the Cloud where each user has access to their own encryption algorithm, an algorithm that is based on a set of iterated function systems that outputs a chaotic number stream, designed to produce a cryptographically secure cipher. …

Obtaining Speech Assets For Judgement Analysis On Low-Pass Filtered Emotional Speech, John Snel, Charlie Cullen

Conference papers

Investigating the emotional content in speech from acoustic characteristics requires separating the semantic con- tent from the acoustic channel. For natural emotional speech, a widely used method to separate the two channels is the use of cue masking. Our objective is to investigate the use of cue masking in non-acted emotional speech by analyzing the extent to which filtering impacts the perception of emotional content of the modified speech material. However, obtaining a corpus of emotional speech can be quite difficult whereby verifying the emotional content is an issue thoroughly discussed. Currently, speech research is showing a tendency toward constructing …

On Improving Electrooculogram-Based Computer Mouse Systems: The Accelerometer Trigger, Johnalan Keegan, Edward Burke, James Condron, Eugene Coyle

Conference Papers

Eye tracking is a well-established method of computer control for profoundly paralysed people (Anson et al., 2002). Cameras are commonly used to track eye movements (Morimoto et al., 2005) but one alternative is the bioelectrical signal known as the electrooculogram (EOG). There are some EOG mouse control systems that facilitate the use of GUI applications, but certain actions, which are straightforward using a conventional mouse, remain impossible. Unless the eyes are tracking a target, they move in saccades (jumps), making it impossible to voluntarily trace out smooth trajectories with one's gaze, as would be required to draw a smooth curve. …

Simulated Performance Intensity Functions, Andrew Hines, Naomi Harte

Conference papers

Measuring speech intelligibility for different hearing aid fitting methods in a simulated environment would allow rapid prototyping and early design assessment. A simulated performance intensity function (SPIF) test methodology has been developed to allow experimentation using an auditory nerve model to predict listeners’ phoneme recognition. The test discriminates between normal hearing and progressively degrading levels of sensorineural hearing loss. Auditory nerve discharge patterns, presented as neurograms, can be subjectively ranked by visual inspection. Here, subjective inspection is substituted with an automated ranking using a new image quality metric that can quantify neurogram degradation in a consistent manner. This work reproduces …

Comparing Hearing Aid Algorithm Performance Using Simulated Performance Intensity Functions, Andrew Hines, Naomi Harte

Conference papers

Simulated performance intensity functions were used to quantitatively discriminate speech intelligibility through phoneme discrimination assessment. Listener test results for subjects with a wide range of sensorineural hearing losses were simulated using an auditory nerve model and compared to real listeners' unaided and aided performance. Simulations of NAL-RP and DSL 4.0 fitting algorithms were compared. Auditory nerve discharge patterns from the model were presented as neurograms. An automated ranking process was used to quantify neurogram degradation using a new measure, the Neurogram Similarity Index Measure (NSIM). The measure has previously been shown to correlate well in predictions of phoneme discrimination for …

Concept-Driven Multi-Modality Fusion For Video Search, Xiao-Yong Wei, Yu-Gang Jiang, Chong-Wah Ngo

Research Collection School Of Computing and Information Systems

As it is true for human perception that we gather information from different sources in natural and multi-modality forms, learning from multi-modalities has become an effective scheme for various information retrieval problems. In this paper, we propose a novel multi-modality fusion approach for video search, where the search modalities are derived from a diverse set of knowledge sources, such as text transcript from speech recognition, low-level visual features from video frames, and high-level semantic visual concepts from supervised learning. Since the effectiveness of each search modality greatly depends on specific user queries, prompt determination of the importance of a modality …

Predictive And Adaptive Game Development A Practical Application Of Development Models To The Independent Video Game Industry, Liam A. Hunt

Theses : Honours

Through the process of researching a number of game and system development models, this study defines two archetypical development models - the predictive and the adaptive. Using each of these models, two video games have been developed in order to measure the practical effect that they can have on the design, development process and player experience of a game. Using the knowledge gained through playtesting and an analysis of the relationship between each game and its development methodology, a number of development guidelines and recommendations have been specifically constructed for use by independent games developers. The practical development and written …

Spiking Neural Networks And Their Applications, Cameron Eric Johnson

Doctoral Dissertations

"Artificial neural networks (ANNs) have been developed as adaptable, robust function approximators for at least the last quarter-century. They have progressed through two generations, and the third is now under development. Spiking neural networks (SNNs) seek to improve on previous generations in two ways: by using a more biologically-inspired neuron, they are shown to be capable of more complex calculations; incorporating polychronous properties of highly-recurrent networks with delays of different lengths on each synapse to achieve large numbers of possible patterns with relatively few neurons and synapses.

Abstracted spiking neurons have been used as a third-generation activation function in a …

An Investigation Into Internetworking Education, Woratat Makasiranondh

Theses: Doctorates and Masters

Computer network technology and the Internet grew rapidly in recent years. Their growth created a large demand from industry for the development of IT and internetworking professionals. These professionals need to be equipped with both technical hands-on skills and non-technical or soft skills. In order to supply new professionals to the industry, educational institutions need to address these skills training in their curricula. Technical hands-on skills in internetworking education can be emphasised through the practical use of equipment in classrooms. The provision of the networking equipment to the internetworking students is a challenge. Particularly, university students in developing countries may …

Agent-Based Analysis And Mitigation Of Failure For Cyber-Physical Systems, Jing Lin

Doctoral Dissertations

"Techniques exist for assessment, modeling, and simulation of physical and cyber infrastructures, respectively; but such isolated analysis is incapable of fully capturing the interdependencies that occur when they intertwine to create a cyber-physical system (CPS). The first contribution of this doctoral research includes qualitative representation of the operation of a CPS in a single multi-agent model. Dependable operation of a CPS is contingent upon correct interpretation of data describing the state of the system. To this end, we propose agent-based semantic interpretation services that extract useful information from raw sensor data. We utilize the summary schemas model to reconcile differences …

Application Of Stochastic Diffusion For Hiding High Fidelity Encrypted Images, Jonathan Blackledge, Abdulrahman Al-Rawi

Articles

Cryptography coupled with information hiding has received increased attention in recent years and has become a major research theme because of the importance of protecting encrypted information in any Electronic Data Interchange system in a way that is both discrete and covert. One of the essential limitations in any cryptography system is that the encrypted data provides an indication on its importance which arouses suspicion and makes it vulnerable to attack. Information hiding of Steganography provides a potential solution to this issue by making the data imperceptible, the security of the hidden information being a threat only if its existence …

Design Of Multi Agent Based Crowd Injury Model, Emin Kugu

Electrical & Computer Engineering Theses & Dissertations

A major concern of many government agencies is to predict and control the behavior of crowds in different situations. Many times such gatherings are legal, legitimate, and peaceful. But there are times when they can turn violent, run out of control, result in material damages and even casualties. It then becomes the duty of governments to bring them under control using a variety of techniques, including non-lethal and lethal weapons, if necessary.

In order to aid decision makers on the course of action in crowd control, there are modeling and simulation tools that can provide guidelines by giving programmed rules …

Spectrum Adaptation In Cognitive Radio Systems With Operating Constraints, Deepak R. Joshi

Electrical & Computer Engineering Theses & Dissertations

The explosion of high-data-rate-demanding wireless applications such as smart-phones and wireless Internet access devices, together with growth of existing wireless services, are creating a shortage of the scarce Radio Frequency (RF) spectrum. However, several spectrum measurement campaigns revealed that current spectrum usage across time and frequency is inefficient, creating the artificial shortage of the spectrum because of the traditional exclusive "command-and-control" model of using the spectrum. Therefore, a new concept of Cognitive Radio (CR) has been emerging recently in which unlicensed users temporarily borrow spectrum from the licensed Primary Users (PU) based on the Dynamic Spectrum Access (DSA) technique that …

An Fpga-Based System For Tracking Digital Information Transmitted Via Peer-To-Peer Protocols, Karl R. Schrader, Barry E. Mullins, Gilbert L. Peterson, Robert F. Mills

Faculty Publications

This paper presents a Field Programmable Gate Array (FPGA)-based tool designed to process file transfers using the BitTorrent Peer-to-Peer (P2P) protocol and VoIP phone calls made using the Session Initiation Protocol (SIP). The tool searches selected control messages in real time and compares the unique identifier of the shared file or phone number against a list of known contraband files or phone numbers. Results show the FPGA tool processes P2P packets of interest 92% faster than a software-only configuration and is 97.6% accurate at capturing and processing messages at a traffic load of 89.6 Mbps.

Integrated Freestanding Single-Crystal Silicon Nanowires: Conductivity And Surface Treatment, Chung-Hoon Lee, Clark Ritz, Minghuang Huang, Michael Ziwisky, Robert Blise, Max Lagally

Electrical and Computer Engineering Faculty Research and Publications

Integrated freestanding single-crystal silicon nanowires with typical dimension of 100 nm × 100 nm × 5 µm are fabricated by conventional 1:1 optical lithography and wet chemical silicon etching. The fabrication procedure can lead to wafer-scale integration of silicon nanowires in arrays. The measured electrical transport characteristics of the silicon nanowires covered with/without SiO₂ support a model of Fermi level pinning near the conduction band. The I–V curves of the nanowires reveal a current carrier polarity reversal depending on Si–SiO₂ and Si–H bonds on the nanowire surfaces

Testing Embedded System Applications, Tingting Yu

School of Computing: Dissertations, Theses, and Student Research

Embedded systems are becoming increasingly ubiquitous, controlling a wide variety of popular and safety-critical devices. Testing is the most commonly used method for validating software systems, and effective testing techniques could be helpful for improving the dependability of these systems. However, there are challenges involved in developing such techniques. Embedded systems consist of layers of software – application layers utilize services provided by underlying system service and hardware support layers. A typical embedded application consists of multiple user tasks. Interactions between application layers and lower layers, and interactions between the various user tasks that are initiated by the application layer, …

Network Security Toolkit Including Heuristic Solutions For Trust System Placement And Network Obfuscation, Gabriel H. Greve

Theses and Dissertations

For Part I, a supervisory control and data acquisition (SCADA) network consists of a group stations and substations in a portion of the power grid. The use of Internet technology in SCADA communications as well as other factors has caused vulnerabilities. One idea to help mitigate this risk is to strategically place trust nodes to compartmentalize and secure the SCADA systems without disturbing its finely honed processes. The trust nodes combine firewall and intrusion detection technology to provide more secure communication. An optimal solution to this problem has already been developed using a mixed-integer linear programming model. Because the problem …

Cross-Layer Optimized Wireless Multimedia Networking, Dalei Wu

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

Multimedia communications, especially real-time video communications, is expected to be the major application of the next-generation wireless networks. However, bringing delay-sensitive and loss-tolerant multimedia services based on the current wireless Internet is a very challenging task. In this dissertation, we address cross-layer optimized wireless multimedia networking from both theoretical and practical perspectives. In the first part of the dissertation, we propose cross-layer optimization frameworks for real-time video communications over wireless networks, where the expected received video quality is adopted as the objective function. With the user-centric objective function, we first study content-aware video communications in single-hop wireless networks by exploring …

A Comprehensive Analysis Of Lte Physical Layer, Fahimeh Rezaei

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

The 3rd Generation Partnership Project (3GPP) introduced Long Term Evolution (LTE) as the 3rd generation of mobile communication standards. LTE Release 8 describes a mobile communication standard which supports up to 300 Mbps of data transmission in downlink using the OFDM scheme as well as up to 75 Mbps throughput for uplink using the SC-FDMA modulation. In this thesis, an in-depth study of LTE performance based on Release 8 is conducted for uplink and downlink under different scenarios. The main objective of this study is to investigate a comprehensive analysis of physical layer throughput of LTE Release8 based on standard …

Intelligent Planning And Assimilation Of Auv-Obtained Measurements Within A Roms-Based Ocean Modeling System, Benjamin J. Davini

Master's Theses

Efforts to learn more about the oceans that surround us have increased dramatically as the technological ability to do so grows. Autonomous Underwater Vehicles (AUVs) are one such technological advance. They allow for rapid deployment and can gather data quickly in places and ways that traditional measurement systems (bouys, profilers, etc.) cannot. A ROMS-based data assimilation method was developed that intelligently plans for and integrates AUV measurements with the goal of minimizing model standard deviation. An algorithm developed for this system is first described that optimizes paths for AUVs that seeks to improve the model by gathering data in high-interest …

Estimating Mean Under Interval Uncertainty And Variance Constraint, Ali Jalal-Kamali, Luc Longpre, Misha Kosheleva

Departmental Technical Reports (CS)

Universal Approximation With Uninorm-Based Fuzzy Neural Networks, Andre Lemos, Vladik Kreinovich, Walmir Caminhas, Fernando Gomide

Departmental Technical Reports (CS)

Fuzzy neural networks are hybrid models capable to approximate functions with high precision and to generate transparent models, enabling the extraction of valuable information from the resulting topology. In this paper we will show that the recently proposed fuzzy neural network based on weighted uninorms aggregations uniformly approximates any real functions on any compact set. We will describe the network topology and inference mechanism and show that the universal approximation property of this network is valid for a given choice of operators.

Testing Shock Absorbers: Towards A Faster Parallelizable Algorithm, Christian Servin

Departmental Technical Reports (CS)

Cars are equipped with shock absorbers, which are designed to smooth out the shocks on the road. In practice, there is a need to test them. To test the shock absorbers, we need to estimate the values of the shock absorber's parameters. If we did not have any measurement errors, then two measurements would be sufficient to determine the parameters. However, in reality, there are measurement errors. Usually, in engineering practice, it is assumed that the errors are normally distributed with 0 mean, so we can use least squares method to test it. In practice, we often only know the …

Fundamental Physical Equations Can Be Derived By Applying Fuzzy Methodology To Informal Physical Ideas, Eric Gutierrez, Vladik Kreinovich

Departmental Technical Reports (CS)

Fuzzy methodology transforms expert ideas -- formulated in terms of words from natural language -- into precise rules and formulas. In this paper, we show that by applying this methodology to intuitive physical ideas, we can get fundamental physical equations. This fact provides an additional justification for the fuzzy methodology.

From Single To Double Use Expressions, With Applications To Parametric Interval Linear Systems: On Computational Complexity Of Fuzzy And Interval Computations, Joseph A Lorkowski

Departmental Technical Reports (CS)

In many practical problems, we need to estimate the range of a given expression f(x1, ..., xn) when each input xi belongs to a known interval [xi] -- or when each input xi is described by a known fuzzy set. It is known that this problem is easy to solve when we have a Single Use Expression, i.e., an expression in which each variable xi occurs only once. In this paper, we show that for similarly defined Double Use Expressions, the corresponding range estimation problem is NP-hard. Similar problems are analyzed for the problem of solving linear systems under interval …

Reducing Over-Conservative Expert Failure Rate Estimates In The Presence Of Limited Data: A New Probabilistic/Fuzzy Approach, Carlos M. Ferregut, F. Joshua Campos, Vladik Kreinovich

Departmental Technical Reports (CS)

Unique highly reliable components are typical for aerospace industry. For such components, due to their high reliability and uniqueness, we do not have enough empirical data to make statistically reliable estimates about their failure rate. To overcome this limitation, the empirical data is usually supplemented with expert estimates for the failure rate. The problem is that experts tend to be -- especially in aerospace industry -- over-cautious, over-conservative; their estimates for the failure rate are usually much higher than the actual observed failure rate. In this paper, we provide a new fuzzy-related statistically justified approach for reducing this over-estimation.