Engineering Commons^™

Metal-Semiconductor-Metal (Msm) Photodetectors With Plasmonic Nanogratings, Narottam K. Das, Ayman Karar, C L Tan, Mikhail Vasiliev, Kamal Alameh, Yong Tak Lee

Research outputs 2011

We discuss the light absorption enhancement factor dependence on the design of nanogratings inscribed into metal-semiconductor-metal photodetector (MSM-PD) structures. These devices are optimized geometrically, leading to light absorption improvement through plasmon-assisted effects. Finite-difference time-domain (FDTD) simulation results show ~50 times light absorption enhancement for 850 nm light due to improved optical signal propagation through the nanogratings. Also, we show that the light absorption enhancement is strongly dependent on the nanograting shapes in MSM-PDs.

High-Responsivity Plasmonics-Based Gaas Metal-Semiconductor-Metal Photodetectors, Ayman Karar, Narottam Das, Chee Leongtan, Kamal Alameh, Yong Tak Lee, Fouad Karouta

Research outputs 2011

We report the experimental characterization of high-responsivity plasmonics-based GaAs metal-semiconductor-metal photodetector (MSM-PD) employing metal nano-gratings. Both the geometry and light absorption near the designed wavelength are theoretically and experimentally investigated. The measured photocurrent enhancement is 4-times in comparison with a conventional single-slit MSM-PD. We observe reduction in the responsivity as the bias voltage increases and the input light polarization varies. Our experimental results demonstrate the feasibility of developing a high-responsivity, low bias-voltage high-speed MSM-PD.

Correlations Between Index Properties And Unconfined Compressive Strength Of Weathered Ocala Limestone, Raoaa Farah

UNF Graduate Theses and Dissertations

Weathering has a negative effect on both physical and engineering properties of rock specimens and rock masses. When rock masses are weathered it is often difficult to obtain core segments that are the correct size for unconfined compressive strength testing. Thus engineers must use index testing to estimate the strength of specimens for design purposes. This thesis relates the unconfined compressive strength to index strength tests of Ocala limestone. The relationships developed include weathering states of the specimens and proximity of unconfined compressive strength specimens to index specimens.

One hundred and ninety five specimens were classified using International Society for …

Forward Error Correction In Memoryless Optical Modulation, David Rhys Jones

UNF Graduate Theses and Dissertations

The unprecedented growth in demand for digital media has led to an all-time high in society’s demand for information. This demand will in all likelihood continue to grow as technology such as 3D television service, on-demand video and peer-to-peer networking continue to become more common place. The large amount of information required is currently transmitted optically using a wavelength division multiplexing (WDM) network structure. The need to increase the capacity of the existing WDM network infrastructure efficiently is essential to continue to provide new high bandwidth services to end-users, while at the same time minimizing network providers’ costs. In WDM …

Preserving Useful Info While Reducing Noise Of Physiological Signals By Using Wavelet Analysis, Jeffrey Lam

UNF Graduate Theses and Dissertations

Wavelet analysis is a powerful mathematical tool commonly used in signal processing applications, such as image analysis, image compression, image edge detection, and communications systems. Unlike traditional Fourier analysis, wavelet analysis allows for multiple resolutions in the time and frequency domains; it can preserve time information while decomposing a signal spectrum over a range of frequencies. Wavelet analysis is also more suitable for detecting numerous transitory characteristics, such as drift, trends, abrupt changes, and beginnings and ends of events. These characteristics are often the most important and critical part of some non-stationary signals, such as physiological signals. The thesis focuses …

Floorplan Design And Yield Enhancement Of 3-D Integrated Circuits, Rajeev Kumar Nain

Dissertations and Theses

We have developed a placement-aware 3-D floorplanning algorithm that enables additional wirelength reduction by planning for 3-D placement of logic gates in selected circuit modules during the floorplanning stage. Thus it also bridges the existing gap between 3-D floorplanning and 3-D placement. To reduce the solution space of 3-D floorplanning which is known to be an NP-hard problem, we derive a set of feasibility conditions on the topological representation of a floorplan. In addition, we have designed a fast module packing algorithm that satisfies a set of constraints for placement-aware 3-D floorplanning. Furthermore, we have designed an efficient evolutionary algorithm …

A Feasibility Study Of Model-Based Natural Ventilation Control In A Midrise Student Dormitory Building, Steven James Gross

Dissertations and Theses

Past research has shown that natural ventilation can be used to satisfy upwards of 98% of the yearly cooling demand when utilized in the appropriate climate zone. Yet widespread implementation of natural ventilation has been limited in practice. This delay in market adoption is mainly due to lack of effective and reliable control. Historically, control of natural ventilation was left to the occupant (i.e. they are responsible for opening and closing their windows) because occupants are more readily satisfied when given control of the indoor environment. This strategy has been shown to be effective during summer months, but can lead …

Fatigue Testing And Computational Analysis Of A Spinal Implant, Timothy Helton

Electronic Theses and Dissertations

The following study investigates the fatigue behavior of a spinal implant developed by Synthes, Inc. to provide stability and off load pressure from the discs in the lumbar region. The installation process for the StenoFix design utilizes plastic deformations to customize the device to each individual patient, but also has potential to degrade fatigue behavior. Physical testing of two titanium alloys, Ti-6Al-7Nb and Ti-15Mo, was conducted on hydraulic test frames and compared to computational simulations which were carried out for the following scenarios: cyclic excitation following plastic deformation; variation of material property definition; variation of loading location; and three modifications …

Bayesian Method For Groundwater Quality Monitoring Network Analysis, K. Ammar, Mac Mckee, Jagath J. Kaluarachchi, H. Moe, M. Almasri, A. Khalil

Civil and Environmental Engineering Faculty Publications

: A new methodology is developed to analyze existing monitoring networks. This methodology incorporates different aspects of monitoring, including vulnerability/probability assessment, environmental health risk, the value of information, and redundancy reduction. A conceptual framework for groundwater quality monitoring is formulated to represent the methodology‚Äôs context. Relevance vector machine RVM plays a basic role in this conceptual framework, and is employed to reduce redundancy and to create probability map of contaminant distribution, and accordingly to estimate the expected value of sample information. Disability adjusted life years approach of the global burden of disease is used for quantifying the health risk consequences. …

Parameter Dependent Convergence Bounds And Complexity Measure For A Class Of Conceptual Hydrological Models, S. Pande, L. Bastidas, S. Bhulai, Mac Mckee

Civil and Environmental Engineering Faculty Publications

We provide analytical bounds on convergence rates for a class of hydrologic models and consequently derive a complexity measure based on the Vapnik–Chervonenkis (VC) generalization theory. The class of hydrologic models is a spatially explicit interconnected set of linear reservoirs with the aim of representing globally nonlinear hydrologic behavior by locally linear models. Here, by convergence rate, we mean convergence of the empirical risk to the expected risk. The derived measure of complexity measures a model’s propensity to overfit data. We explore how data finiteness can affect model selection for this class of hydrologic model and provide theoretical results on …

Evaluation Of The Physicochemical Properties And Stability Of Solid Lipid Nanoparticles Designed For The Delivery Of Dexamethasone To Tumors, Melissa Howard

University of Kentucky Doctoral Dissertations

Pre-clinical and clinical trials suggest that pre-treatment with dexamethasone (Dex) may facilitate enhanced uptake of subsequently administered chemotherapeutic agents. To reduce the side effects associated with systemic administration of Dex, solid lipid nanoparticles (SLNs) containing dexamethasone palmitate (Dex-P) were prepared as a means of achieving tumor-targeted drug delivery. These studies were aimed at evaluating the physicochemical properties and both the physiological and storage stability of the SLNs.

SLNs were prepared using nanotemplate engineering technology. Stearyl alcohol (SA) was used as the lipid phase with Brij^® 78 and Polysorbate 60 as surfactants and PEG6000 monostearate as a long-chain PEGylating agent. …

Resource Allocation And Efficient Routing In Wireless Networks, Jianjun Yang

University of Kentucky Doctoral Dissertations

In wireless networks, devices (nodes) are connected by wireless links. An important issue is to set up high quality (high bandwidth) and efficient routing paths when one node wants to send packets to other nodes. Resource allocation is the foundation to guarantee high quality connections. In addition, it is critical to handle void areas in order to set up detour-free paths. Moreover, fast message broadcasting is essential in mobile wireless networks. Thus, my research includes dynamic channel allocation in wireless mesh networks, geographic routing in Ad Hoc networks, and message broadcasting in vehicular networks.

The quality of connections in a …

Initial Design, Manufacture, And Testing Of A Cubelab Module Frame For Biological Payloads Aboard The International Space Station, Twyman Samuel Clements

University of Kentucky Master's Theses

This thesis investigates the design of a CubeLab Module frame to facilitate biological research aboard the International Space Station (ISS). With the National Laboratory designation of the ISS by the United States Congress the barriers for use of the facility have been lowered for commercial and academic entities, allowing greater volume and diversity in the research that can be done. Researchers in biology and other areas could benefit from development and adoption of a plug-and-play payload containment system for use in the microgravity/space environment of the ISS. This research includes design and analysis of such a system. It also includes …

Constrained Volume Packing Of Deployable Wings For Unmanned Aircraft, Turner John Harris

University of Kentucky Master's Theses

UAVs are becoming an accepted tool for sensing. The benefits of deployable wings allow smaller transportation enclosures such as soldier back packs up to large rocket launched extraterrestrial UAVs. The packing of soft inflatable wings and Hybrid inflatable with rigid section wings is being studied at the University of Kentucky. Rigid wings are volume limited while inflatable wings are mass limited. The expected optimal wing design is a hybrid approach. Previous wing designs have been packed into different configurations in an attempt to determine the optimal stowed configurations. A comparison of rigid, hybrid, and inflatable wings will be presented. Also …

Perch Landing Maneuvers And Control For A Rotating-Wing Mav, Jonathan Louis Lubbers

University of Kentucky Master's Theses

This thesis addresses flight control of the perch landing maneuver for micro-aerial vehicles. A longitudinal flight model is constructed for a pigeon-sized aircraft. In addition to a standard elevator control surface, wing-rotation also considered as a non-standard actuator for increasing low-speed aerodynamic braking. Optimal state and control trajectories for the perch landing maneuver are computed using commercial software. A neighboring optimal control law is then developed and implemented in a set of flight simulations. Simulations are run with both a quasisteady and an unsteady aerodynamic model. The effectiveness of wing rotation and of the neighboring optimal control law is discussed, …

New Catalysts For The Photocatalytic Reduction Of Carbon Dioxide To C1 Organic Compounds, Anna Hailey

Honors Theses

Photocatalytic reduction of carbon dioxide (CO2) has recently been identified as one of the five notable research areas in catalysis because it simultaneously reduces carbon emissions while storing clean, green solar energy in organic compounds. The development of efficient photocatalysts that take advantage of solar radiation is therefore an important area of research. Titanium dioxide (TiO2) is a commonly-used photocatalyst for this reaction, but it requires ultraviolet (UV) radiation to excite its electrons. Carbon-doping (C-doping) has been shown to reduce the intensity of energy required, thus allowing the photocatalyst to take advantage of the visible light spectrum. Copper (Cu), added …

Dynamic Simulation Of A High Pressure Regulator, A. Shahani, H. Esmaili, Ashkan Aryaei, S. Mohammadi, M. Najar

Faculty Publications

In this paper, the dynamic simulation for a high pressure regulator is performed to obtain the regulator behavior. To analyze the regulator performance, the equation of motion for inner parts, the continuity equation for diverse chambers and the equation for mass flow rate were derived. Because of nonlinearity and coupling, these equations are solved using numerical methods and the results are presented. Additionally, the dynamic analysis results consist of the output pressure change versus time, the displacement of the moving parts versus time, the regulator mass flow rate versus time and the output pressure versus mass flow rate in different …

The Synthesis And Host-Guest Applications Of Synthetic Receptor Molecules, Zachary Richard Osner

Dissertations

Host-guest chemistry involves the complimentary binding between two molecules. Host molecules have been synthesized to bind negative, positive, and neutral molecules such as proteins and enzymes, and have been used as optical sensors, electrochemical sensors, supramolecular catalysts, and in the pharmaceutical industry as anti-cancer agents.1 The field of nanoscience has exploited guest-host interactions to create optical sensors with colloidal gold and Dip-Pen nanolithography technologies. Gold nanoparticles, have been functionalized with DNA, and have been developed as a selective colorimetric detection system, that upon binding turns the solution from a red to blue in color.2

Cyclotriveratrylene (CTV) 1 is a common …

Table Of Contents

Journal of Digital Forensics, Security and Law

No abstract provided.

A Survey Of Contemporary Enterprise Storage Technologies From A Digital Forensics Perspective, Gregory H. Carlton, Joseph Matsumoto

Journal of Digital Forensics, Security and Law

As the proliferation of digital computational systems continue to expand, increasingly complex technologies emerge, including those regarding large, enterprise-wide, information storage and retrieval systems. Within this study, we examine four contemporary enterprise storage technologies. Our examination of these technologies is presented with an overview of the technological features of each offering and then followed with a discussion of the impact of these technologies on digital forensics methods, particularly regarding forensic data acquisition. We offer a general opinion concerning a recommended data acquisition method when faced with the task of obtaining a forensic image of data contained within these technologies, we …

Legal Issues Regarding Digital Forensic Examiners Third Party Consent To Search, Thomas Lonardo, Doug White, Tricia P. Martland, Alan Rea

Journal of Digital Forensics, Security and Law

This paper focuses on Federal law as it relates to consent to search relating to Fourth Amendment privacy in the practice of Digital Forensics. In particular, Digital Examiners should be aware of how decisions in Federal Court may impact their ability to acquire evidence in both civil and criminal settings. Digital Forensics, being a relatively new field, is particularly subject to change as cases and appeals are decided. This paper provides an overview of relevant case law relating to issues in Digital Forensics. More importantly, our research provides Digital Forensic Examiners (DFE), as defined by Lonardo, White, and Rea (2008, …

Exploring The Iphone Backup Made By Itunes, Mario Piccinelli, Paolo Gubian

Journal of Digital Forensics, Security and Law

Apple’s™ iPhone™ is one of the widest selling mobile on the market, thanks to its simple and user-friendly interface and ever growing pool of available high quality applications for both personal and business use. The increasing use of the iPhone leads forensics practitioners towards the need for tools to access and analyze the information stored in the device. This research aims at describing the process to forensically analyze a logical backup of an iPhone made by the Apple iTunes™ utility, understanding the backup’s structure, and creating a simple tool to automate the process of decoding and analyzing the data. In …

A Case Study In Forensic Analysis Of Control, Fred Cohen

Journal of Digital Forensics, Security and Law

This paper describes a case study in which a method for forensic analysis of control was applied to resolve probative technical issues in a legal action. It describes one instance in which the analysis was successfully applied without challenge, addresses the details of most of the different facets of the analysis method, and demonstrates how such analysis provides a systematic approach to using technical methods to address legal issues as a case study.

Extraction Of Electronic Evidence From Voip: Forensic Analysis Of A Virtual Hard Disk Vs Ram, David Irwin, Jill Slay, Arek Dadej, Malcolm Shore

Journal of Digital Forensics, Security and Law

The popularity of Voice over the Internet Protocol (VoIP) is increasing as the cost savings and ease of use is realised by a wide range of home and corporate users. However, the technology is also attractive to criminals. This is because VoIP is a global telephony service, in which it is difficult to verify the user’s identification. The security of placing such calls may also be appealing to criminals, as many implementations use strong encryption to secure both the voice payload as well as to control messages making monitoring such VoIP calls difficult since conventional methods such as wire-tapping is …

Table Of Contents

Journal of Digital Forensics, Security and Law

No abstract provided.

Book Review: Ios Forensic Analysis: For Iphone, Ipad And Ipod Touch, Christopher Schulte

Journal of Digital Forensics, Security and Law

As Digital Forensics practitioners, we know that our discipline is constantly evolving. Keeping abreast means we need to continually refine and broaden our knowledge pools through experience, education, research, peer exchange, and more. Mobile device forensics can be especially dynamic and challenging. With multiple standards in place at the hardware, operating system, and user interface levels, it can be daunting to preserve, analyze, search and report on these tiny yet ubiquitous hand-held computers. Apple Computer’s line of mobile products (iOS devices - iPhone, iPad, iPod Touch) is no exception to this rule.

Column: Every Last Byte, Simson Garfinkel

Journal of Digital Forensics, Security and Law

Inheritance powder is the name that was given to poisons, especially arsenic, that were commonly used in the 17th and early 18th centuries to hasten the death of the elderly. For most of the 17th century, arsenic was deadly but undetectable, making it nearly impossible to prove that someone had been poisoned. The first arsenic test produced a gas—hardly something that a scientist could show to a judge. Faced with a growing epidemic of poisonings, doctors and chemists spent decades searching for something better

Technology Corner: Brute Force Password Generation -- Basic Iterative And Recursive Algorithms, Nick V. Flor, Haile Shannon

Journal of Digital Forensics, Security and Law

Most information systems are secured at minimum by some form of password protection. For various reasons a password may be unavailable, requiring some form of password recovery procedure. One such procedure is software-based automated password recovery, where a program attempts to log into a system by repeatedly trying different password combinations. At the core of such software is a password generator. This article describes the basic iterative and recursive algorithms for generating all possible passwords of a given length, which is commonly referred to as brute-force password generation. The paper ends with a discussion of alternative password recovery procedures one …

Primary And Secondary Incident Management: Predicting Durations In Real Time, Asad J. Khattak, Xin Wang, Hongbing Zhang, Mecit Cetin

Civil & Environmental Engineering Faculty Publications

Traffic incidents are a major source of congestion in Virginia. Secondary incidents comprise a relatively small but important portion of all incidents, and relatively little is known about their occurrence, characteristics, and associated delays. The main objectives of this study were to define secondary incidents, understand and analyze the occurrence and nature of such incidents, and develop tools that can comprehensively and continuously analyze primary and secondary incidents at the planning and operational levels, ultimately contributing to congestion management. The scope of the study is limited to freeway incidents in the Hampton Roads (HR) area. The study found that secondary …

Eeg Artifact Removal Using A Wavelet Neural Network, Hoang-Anh T. Nguyen, John Musson, Jiang Li, Frederick Mckenzie, Guangfan Zhang, Roger Xu, Carl Richey, Tom Schnell, Thomas E. Pinelli (Ed.)

Electrical & Computer Engineering Faculty Publications

In this paper we developed a wavelet neural network. (WNN) algorithm for Electroencephalogram (EEG) artifact removal without electrooculographic (EOG) recordings. The algorithm combines the universal approximation characteristics of neural network and the time/frequency property of wavelet. We compared the WNN algorithm with the ICA technique and a wavelet thresholding method, which was realized by using the Stein's unbiased risk estimate (SURE) with an adaptive gradient-based optimal threshold. Experimental results on a driving test data set show that WNN can remove EEG artifacts effectively without diminishing useful EEG information even for very noisy data.