Engineering Commons^™

Correlation-Space Description Of The Percolation Transition In Composite Microstructures, Megan E. Frary, Christopher A. Schuh

Materials Science and Engineering Faculty Publications and Presentations

We explore the percolation threshold shift as short-range correlations are introduced and systematically varied in binary composites. Two complementary representations of the correlations are developed in terms of the distribution of phase bonds or, alternatively, using a set of appropriate short-range order parameters. In either case, systematic exploration of the correlation space reveals a boundary that separates percolating from nonpercolating structures and permits empirical equations that identify the location of the threshold for systems of arbitrary short-range correlation states. Two- and three-dimensional site lattices with two-body correlations, as well as a two-dimensional hexagonal bond network with three-body correlations, are explored. …

Perceptions Of Age Discrimination, Organizational Justice, And Employee Attitudes On Intentions To Leave In The Engineering Industry, Courtney L. Bibby

Graduate Student Dissertations, Theses, Capstones, and Portfolios

The U.S. Department of Labor, Bureau of Labor Statistics (2006) reported that the annual turnover rate for employees of U.S. firms rose to 41% in 2005. Employee intentions to leave among young adults are a concern in many industries where the demand for skilled employees begins to exceed the supply. This is especially true in the engineering industry, because talented and knowledgeable employees are difficult to replace.

Employee turnover represents a practical dilemma for many businesses due to the loss of qualified personnel and additional recruitment and training costs. Although little is known about employee turnover intention within the engineering …

A Comparison Of Five Models For Estimating Clear-Sky Solar Radiation, Robert Leslie Annear, Scott A. Wells

Civil and Environmental Engineering Faculty Publications and Presentations

Many agencies in the USA are developing management approaches to address water quality concerns and threatened and endangered species habitat requirements in water bodies. Many of these water bodies are water quality limited for temperature. Factors influencing stream temperature include: streamside vegetation, topographic shading, inflows and outflows, stream width, stream depth, light extinction and solar radiation. One of the key driving factors in estimating a water body heat budget is calculating the amount of solar radiation incident on the water surface. Even though it is preferable to measure clear-sky solar radiation, many temperature models rely on theoretical estimates of clear-sky …

Work In Progress -- Tailoring Optics Resources For K-5 Pre-College Outreach, Theresa M. Swift, Steve Eugene Watkins

Electrical and Computer Engineering Faculty Research & Creative Works

Pre-college instruction in science, technology, Engineering; and mathematics (STEM) is critical to preparing a workforce and citizens for a technology-based society. The K-5 years are especially important to creating interest and instilling basic concepts. Engineering-based pre-college outreach can provide useful resources in the K- 5 education classroom. However, interaction among K-5 teachers and STEM professionals is more effective if outreach is tailored to the K-5 environment. In particular, resources and outreach should accommodate K-5 assessment standards, level-appropriate concept definition, and grade continuity. This work uses a set of optics resources as an example of tailored outreach. Example lessons and activities …

Phase Transformations Of Calcium Phosphates Formed In Wet Field Environments, O. M. Clarkin, Mark R. Towler, G. M. Insley, M. E. Murphy

Chemical and Biochemical Engineering Faculty Research & Creative Works

The crystal phase and morphology of calcium phosphate salts precipitated in a wet field environment at temperatures between 30 and 70 °C and pHs between 3 and 8 were examined. Dicalcium Phosphate Dihydrate (DCPD) was the most prevalent phase precipitated. Using accelerated ageing study techniques, precipitates studied were aged, under dry conditions at 50 °C for 8 and 16 days, before being re-examined using XRD, FTIR and SEM techniques. DCPD was found to be most stable when precipitated at 40 °C and 5 pH. Considerably more phase transformation to Octacalcium Phosphate (OCP), Amorphous Calcium Phosphate (ACP) and Hydroxyapatite (HA) was …

Comparisons Of An Adaptive Neural Network Based Controller And An Optimized Conventional Power System Stabilizer, Wenxin Liu, Ganesh K. Venayagamoorthy, Jagannathan Sarangapani, Donald C. Wunsch, Mariesa Crow, Li Liu, David A. Cartes

Electrical and Computer Engineering Faculty Research & Creative Works

Power system stabilizers are widely used to damp out the low frequency oscillations in power systems. In power system control literature, there is a lack of stability analysis for proposed controller designs. This paper proposes a Neural Network (NN) based stabilizing controller design based on a sixth order single machine infinite bus power system model. The NN is used to compensate the complex nonlinear dynamics of power system. To speed up the learning process, an adaptive signal is introduced to the NN's weights updating rule. The NN can be directly used online without offline training process. Magnitude constraint of the …

Discussion On Effective Control Of Inter-Area Oscillations By Upfcs, Mahyar Zarghami, Mariesa Crow

Electrical and Computer Engineering Faculty Research & Creative Works

The paper discusses an effective method for damping inter-area oscillations in a power network using UPFCs. This two stage method controls voltage magnitudes/angles of the two sides of the UPFC based on a linearized approach, which in turn will command modulation amplitudes and angles of the UPFC. The method is compared to a one stage linearized approach which directly commands modulation amplitudes and angles of the UPFC. Discussion on the feasibility of the method and its relation to the steady-state operation of the UPFC is also addressed.

Use Of Max-Flow On Facts Devices, Adam Lininger, Bruce M. Mcmillin, Badrul H. Chowdhury, Mariesa Crow

Computer Science Faculty Research & Creative Works

FACTS devices can be used to mitigate cascading failures in a power grid by controlling the power flow in individual lines. Placement and control are significant issues. We present a procedure for determining whether a scenario can be mitigated using the concept of maximum flow. If it can be mitigated, we determine what placement and control setting will solve the scenario. This paper treats fourteen cascading failure scenarios and reports on the use of the max-flow algorithm both in determining the mitigation of each scenario and in finding FACTS settings that will mitigate the scenario.

Lazy Preservation: Reconstructing Websites From The Web Infrastructure, Frank Mccown

Computer Science Theses & Dissertations

Backup or preservation of websites is often not considered until after a catastrophic event has occurred. In the face of complete website loss, webmasters or concerned third parties have attempted to recover some of their websites from the Internet Archive. Still others have sought to retrieve missing resources from the caches of commercial search engines. Inspired by these post hoc reconstruction attempts, this dissertation introduces the concept of lazy preservation{ digital preservation performed as a result of the normal operations of the Web Infrastructure (web archives, search engines and caches). First, the Web Infrastructure (WI) is characterized by its preservation …

A Modular Kernel Linear Discriminant Analysis Of Gabor Features For Improved Face Recognition, Neeharika Gudur

Electrical & Computer Engineering Theses & Dissertations

Automatic face recognition is one of the major challenges in computer vision and pattern analysis. This thesis presents an efficient face recognition system that is robust with regards to changes in illumination, facial expressions and partial occlusions. Modular Kernel Linear Discriminant Analysis performed on Gabor Features obtained from the face images is employed for improving face recognition accuracy. A face image is pre-processed using the 2D Gabor wavelet transform to achieve invariance to illumination in images. Modular approaches that divide the pre-processed images into smaller sub-images provide improved accuracy, as the facial variations in an image are confined to local …

Electroactive Polymers (Eap): Simulation Studies Of The Actuation Mechanisms In A Cantilever Cellulose Electroactive Paper, Fatim A. Mbaye

Electrical & Computer Engineering Theses & Dissertations

Electroactive polymers (EAPs) exhibit large strain in response to an external electric field and have attracted a great deal of attention in recent years for sensor and actuator applications. Favorable properties include soft actuation, ease and simplicity in manufacturing, being light-weight, low power consumption, and the ability to withstand harsh environments. However, this is an emerging material, and several aspects, including the fundamental mechanisms for piezoelectric deflections, remain unclear. This project studies the internal electromechanical factors that contribute to the voltage induced deflections of electro-active paper (EAPap). Experimental measurements of bias dependent deflections and water absorption as a function of …

Neighborhood Defined Adaboost Based Mixture Of Color Components For Efficient Skin Segmentation, Ramya Reddy Maaram

Electrical & Computer Engineering Theses & Dissertations

A skin segmentation algorithm robust to illumination changes and skin-like backgrounds is developed in this thesis. So far skin pixel classification has been limited to only individual color spaces and there has not been a comprehensive evaluation of which color components or combination of color components would provide the best classification accuracy, Color components in a given color space form the feature set for the classification of skin pixels. The combination of the color components or the features present within a single color space may not be the best when it comes to skin pixel classification as the discriminatory power …

Microfabrication Of An Optical Chamber For Exposing Living Cells To Pulsed Electric Fields, Saleh Sheikh

Electrical & Computer Engineering Theses & Dissertations

I have fabricated a chamber which enables the application of Nanosecond Pulsed Electric Fields (nsPEFs) to living cells while monitoring their real time fluorescence with an inverted microscope. The No. I thickness (150µm nominal) coverslip glass substrate used for fabrication allows the use of high numerical aperture oil immersion objectives for imaging intracellular organelles. Electrodes are fabricated by first evaporating a chromium adhesion layer, followed by a nickel seed layer. Subsequently, an ultra-thick positive photoresist is applied and patterned to create a 30µm thick electroplating mold. The electrodes are then electrodeposited into the mold from a nickel sulfamate plating bath. …

Integrating Game Technology And Discrete Event Simulation To Analyze Mass Casualty Scenarios, Jason Loveland

Computational Modeling & Simulation Engineering Theses & Dissertations

In the last 10 years, video games have become complex simulation environments with high resolution 3D graphics enabled by powerhouse rendering engines, multi-player client server networks, user friendly displays and graphical user interface , while remaining relatively inexpensive. There is a critical need for systems engineering analysis and rapid trade studies due to changes in operations caused by current events such as terrorist attacks, asymmetric threats, natural disasters, etc. Modem games provide a unique way to visualize and interact with these complex environments, scenarios, missions, and operations. A discrete event simulator (DES) provides an environment to model system architecture behavior, …

Enhanced Shrinkage Of Lanthanum Strontium Manganite (La0.90sr0.10mno3+Δ) Resulting From Thermal And Oxygen Partial Pressure Cycling, Benjamin P. Mccarthy, Larry R. Pederson, Harlan U. Anderson, Xiao Dong Zhou, Prabhakar Singh, Gregory W. Coffey, Edwin C. Thomsen

Materials Science and Engineering Faculty Research & Creative Works

Exposure of (La_0.90Sr_0.10)_0.98MnO_3+δ (LSM-10) to repeated oxygen partial pressure cycles (air/10 ppm O₂) resulted in enhanced densification rates, similar to behavior shown previously due to thermal cycling. Shrinkage rates in the temperature range 700°-1000°C were orders of magnitude higher than Makipirtti-Meng model estimations based on stepwise isothermal dilatometry results at a high temperature. a maximum in enhanced shrinkage due to oxygen partial pressure cycling occurred at 900°C. Shrinkage was the greatest when LSM-10 bars that were first equilibrated in air were exposed to gas flows of lower oxygen fugacity than in …

On The Reference Length And Mode Mixity For A Bimaterial Interface, A. Agrawal, Anette M. Karlsson

Mechanical Engineering Faculty Publications

We investigate properties that govern interfacial fracture within the framework of linear elastic fracture mechanics, including interfacial fracture toughness, mode mixity,and the associated reference length. The reference length describes the arbitrary location where the mode mixity is evaluated, ahead ofthe crack tip, in a bimaterial system. A method for establishing a reference length that is fixed for a given bimaterial system is proposed. This is referred to as the“characteristic reference length,” with the associated “characteristic mode mixity.” The proposed method is illustrated with an experimental investigation, utilizing a four-point bend test of a bimaterial system.

The Effects Of Contention Among Stations On Video Streaming Applications Over Wireless Local Area Networks: An Experimental Approach, Nicola Cranley, Tanmoy Debnath

Conference papers

Multimedia streaming applications have a large impact on the resource requirements of the WLAN. There are many variables involved in video streaming, such as the video content being streamed, how the video is encoded and how it is sent. This makes the role of radio resource management and the provision of QoS guarantees extremely difficult. For video streaming applications, packet loss and packets dropped due to excessive delay are the primary factors that affect the received video quality. In this paper, we experimentally analyse the effects of contention on the performance of video streaming applications with a given delay constraint …

The Capability Of The Edca Mechanism To Support Voice Traffic In A Mixed Voice/Data Transmission Over 802.11e Wlans: An Experimental Investigation, Miroslaw Narbutt, Mark Davis

Conference papers

In this paper we experimentally evaluate the capability of the EDCA mechanism to support voice traffic in a mixed voice/data transmission over 802.11e WLANs. In particular we investigate how real-time voice transmission can be supported by tuning four EDCA parameters, namely AIFSN, CWmin, CWmax and TXOP and how this impacts on background data transmission. The experimental set-up involves fifteen VoIP terminals sending bi-directional traffic between wired and wireless subnets and another station injecting various types of heavy background load to the wireless subnet. End-to-end voice transmission quality is predicted from time-varying transmission impairments with the use of the latest Appendix …

Ict And Innovation Processes In Small Italian Logistics Companies, Edward Sweeney

Conference papers

No abstract provided.

Training Module In Regional And Municipal Governance Of Public Private Partnerships, Louis Gunnigan

Conference papers

This module concentrates on the issues important to those who will be setting up PPPs and who are involved in government at a regional or municipal level.

The module is centred on five tasks, namely:

• How to identify PPP opportunities and to find the best private sector partners for a PPP;
• How to organize a PPP programme within a government by enhancing cooperation amongst the relevant departments and ministries, local, regional and national authorities;
• How to be an effective manager and leader in a dynamic PPP unit;
• How to engage public support for PPPs;
• How to use international instruments to …

Music Structure Segmentation Using The Azimugram In Conjunction With Principal Component Analysis, Dan Barry, Mikel Gainza, Eugene Coyle

Conference papers

A novel method to segment stereo music recordings into formal musical structures such as verses and choruses is presented. The method performs dimensional reduction on a time-azimuth representation of audio which results in a set of time activation sequences, each of which corresponds to a repeating structural segment. This is based on the assumption that each segment type such as verse or chorus has a unique energy distribution across the stereo field. It can be shown that these unique energy distributions along with their time activation sequences are the latent principal components of the time-azimuth representation. It can be shown …

A Comparison Of State Policies For Complying With The Endangered Species Act, Lenahan O'Connell, Ted Grossardt

Kentucky Transportation Center Research Report

In recent years the number of biological assessments (BAs) for the presence of endangered species conducted by KYTC has risen significantly. This was primarily due to new/additional restrictions imposed by the United States Fish and Wildlife Service (USFWS) in 2005. The most consequential restriction was the listing of the Indiana bat as potentially present in all Kentucky counties. Previously BAs for the Indiana bat were only conducted when a project occurred in a county in which the Indiana bat had been observed (a known occurrence). This study reviewed the policies of the states adjacent to Kentucky, as well as those …

Effect Of Cold Work On The Tensile Properties Of 6061, 2024, And 7075 Al Alloys, D. Ortiz, M. Abdelshehid, R. Dalton, J. Soltero, R. Clark, M. Hahn, E. Lee, W. Lightell, B. Pregger, J. Ogren, P. Stoyanov, Omar S. Es-Said

Mechanical Engineering Faculty Works

Aluminum alloys 6061, 2024, and 7075 were heat treated to various tempers and then subjected to a range of plastic strain (stretching) in order to determine their strain limits. Tensile properties, conductivity, hardness, and grain size measurements were evaluated. The effects of the plastic strain on these properties are discussed and strain limits are suggested.

A Universal Theory Of Pseudocodewords, Nathan Axvig, Emily Price, Eric T. Psota, Deanna Turk, Lance C. Pérez, Judy L. Walker

Department of Mathematics: Faculty Publications

Three types of pseudocodewords for LDPC codes are found in the literature: graph cover pseudocodewords, linear programming pseudocodewords, and computation tree pseudocodewords. In this paper we first review these three notions and known connections between them. We then propose a new decoding rule — universal cover decoding — for LDPC codes. This new decoding rule also has a notion of pseudocodeword attached, and this fourth notion provides a framework in which we can better understand the other three.

A Site-Wide Perspective On Uranium Geochemistry At The Hanford Site, John M. Zachara, C. Brown, J. Christensen, J.A. Davis, E. Dresel, Chongxuan Liu, S. Kelly, James Mckinley, J. Serne, W. Um

United States Department of Energy: Publications

Uranium (U) is an important risk-driving contaminant at the Hanford Site. Over 200,000 kg have been released to the vadose zone over the course of site operations, and a number of vadose zone and groundwater plumes containing the uranyl cation [UO₂²⁺, U(VI)] have been identified. U is recognized to be of moderate-to-high mobility, conditions dependent. The site is currently making decisions on several of these plumes with long-lasting implications, and others are soon to come.

Uranium is one of nature’s most intriguing and chemically complex elements. The fate and transport of U(VI) has been studied over the …

Ceg 220: Introduction To C Programming For Engineers I, Jay Dejongh

Computer Science & Engineering Syllabi

This course provides a general introduction to computers as a problem-solving tool using the C programming language. Emphasis is on algorithms and techniques useful to engineers. Topics include data representation, debugging, and program verification. 4 credit hours. Prerequisite: MTH 229 (Calculus I) or EGR 101 (Engineering Mathematics).

Cs 405/605: Introduction To Database Management Systems, Soon M. Chung

Computer Science & Engineering Syllabi

Survey of logical and physical aspects of database management systems. Entity Relationship, relational, object-oriented models for databases are presented. Physical implementation methods are discussed.

Signaling Pathways Activated By Interleukin-2 And Interluekin-4 Receptors Mediate T Lymphocyte Clonal Expansion, Kristen K. Comfort

Chemical and Materials Engineering Faculty Publications

Cells sense and respond to chemical and physical stimuli through signal transduction pathways, which mediate cell proliferation, differentiation, migration, and survival. The cytokines interleukin-2 (IL-2) and interleukin-4 (IL-4) are key regulators of the adaptive immune system, particularly influencing the clonal expansion and differentiation of T cells. At least in culture, both synergistic and antagonistic effects of IL-2 and IL-4 co-stimulation have been reported; the antagonism, when observed, is thought to arise from the utilization of a common subunit shared by IL-2 and IL-4 receptors. We have sought to characterize IL-2 and IL-4 signaling at the level of intracellular pathways activated …

Cascading Line Outage Prevention With Multiple Upfcs, Hong Tao Ma, Mariesa Crow, Badrul H. Chowdhury, Adam Lininger

Electrical and Computer Engineering Faculty Research & Creative Works

Flexible AC Transmission System (FACTS) have been recognized to be effective in regulating network power flow and enhance system dynamic performance. In this paper, multiple UPFCs are integrated into a network and controlled according to the Max Flow algorithm to avoid possible cascading line outage. The dynamic response of UPFC controllers and generator performance are investigated with potential cascading critical line outage. Cascading blackout prevention is investigated not only for steady state power flow overload problem but also for system dynamic stability problem. Generator performances of speed deviation, angle deviations and bus voltage profile as well as dynamic power flows …

Energy-Efficient Hybrid Key Management Protocol For Wireless Sensor Networks, Timothy J. Landstra, Maciej Jan Zawodniok, Jagannathan Sarangapani

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, we propose a subnetwork key management strategy in which the heterogeneous security requirements of a wireless sensor network are considered to provide differing levels of security with minimum communication overhead. Additionally, it allows the dynamic creation of high security subnetworks within the wireless sensor network and provides subnetworks with a mechanism for dynamically creating a secure key using a novel and dynamic group key management protocol. The proposed energy-efficient protocol utilizes a combination of pre-deployed group keys and initial trustworthiness of nodes to create a level of trust between neighbors in the network. This trust is later …