Engineering Commons^™

Plasma Arc Torch Technology Stabilization And Ground Improvement, Purdue Ect Team

ECT Fact Sheets Archive

This technology represents an additional alternative for stabilizing weak foundation soils upon which buildings, bridges, roads or other structures are to be constructed. A plasma is a gas that has been ionized by the electric arc of a plasma torch and can therefore respond to electrical and magnetic fields. Plasma arc technology can create plasma using almost any type of gas (oxygen, nitrogen, carbon monoxide, air, etc.) and in a wide range of pressures (vacuum to 20 atmospheres).

Gas-Liquid Mass Transfer In A High Pressure Bubble Column Reactor With Different Sparger Designs, Lu Han, Muthanna H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

The Gas-Liquid Mass Transfer in a 0.162 M High-Pressure Stainless-Steel Bubble Column Was Investigated using Three Different Gas Sparger Designs. an Oxygen-Enriched-Air Dynamic Method and an Optical Oxygen Probe Technique Were Implemented to Measure K1 a Values in the Bubble Column Reactor. using the Interfacial Area (A) Values Measured by a Four-Point Optical Probe Technique at Similar Conditions (Xue, 2004), the K1 Values Were Estimated. Axial Dispersion Model (ADM) and Continuous Stirred Tank Reactor (CSTR) Model Were Used to Calculate K1 a as a Fitted Parameter with the Measured Data. the ADM Gave Better Fits to the Experimental Data Than …

Development Of An Intelligent Autonomous Coffee Maker, Nicholas J. Vanderpool

Browse all Theses and Dissertations

Using Intelligent Control Methodology Home coffee machines have improved over time with the addition of features such as self-activating timers and crude temperature controlled heating elements. However, home coffee brewer development has stagnated and has yet to achieve full automation status. Present coffee machines leave the user burdened with the mundane and messy task of preparing the coffee maker every time. Also, should the user decide to prepare less than an entire pot, he/she must estimate the correct amount of water and coffee to add. This can lead to a weak or strong brew, giving undesirable results. In order to …

Assessment Of Dynamic Contrast Enhanced Mri For The Early Detection Of Treatment Response In Human Advanced Hepato-Cellular Carcinoma, Yun Jiang

All ETDs from UAB

Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) has been shown to be a potentially useful tool for early prediction of tumor response to antiangiogenesis agents. In this study, the technique was used to evaluate the chemotherapeutic drug doxorubicin with or without the tyrosine kinase inhibitor sorafenib in patients with advanced hepatocellular carcinoma (HCC). Five male patients (ages 50 to 78 years, average age 67  8 years) were studied with serial T1-weighted DCE-MRI to measure the alteration of perfusion parameters of tumors in response to the treatment. All patients received doxorubicin at dose of 60 mg/m2 intravenously every 21 days. Among …

Increasing Effectiveness Of Public Private Partnerships In The Irish Construction Industry, Louis Gunnigan

Doctoral

By 2003 the first Irish Public Private Partnership (PPP) projects had reached the operational stage. Media reports were emerging of significant differences in the effectiveness of these projects.

This research set out to find a means by which effectiveness of PPPs could be increased and to develop a model that would assist PPP practitioners with this task in the future. Through a literature review, the Irish PPP process was mapped, the changes encountered in the introduction of PPP were investigated and a conceptual model – based on a traditional process model - was proposed. The model was tested by examining …

Increasing Effectiveness Of Public Private Partnerships In The Irish Construction Industry, Louis Gunnigan

Doctoral

By 2003 the first Irish Public Private Partnership (PPP) projects had reached the operational stage. Media reports were emerging of significant differences in the effectiveness of these projects.

This research set out to find a means by which effectiveness of PPPs could be increased and to develop a model that would assist PPP practitioners with this task in the future. Through a literature review, the Irish PPP process was mapped, the changes encountered in the introduction of PPP were investigated and a conceptual model – based on a traditional process model - was proposed. The model was tested by examining …

Reinventing A Level 7 Programme In Electrical Engineering And Greatly Improving On Student Retention, Eugene Coyle, Mike Murphy, Frank Costello, Leslie Shoemaker

Books/Book chapters

Following the successful implementation over a number of decades of a three-year Diploma in Electrical and Control Engineering at Technological University Dublin, the programme entered a period of extreme difficulty and uncertainty in the late nineteen ninetees and early years of the new millennium. As with many such engineering programmes, student numbers seeking to enter began to diminish. Furthermore, engagement and retention of students who had enrolled on the programme became evermore challenging, necessitating some radical moves in the formation and operation of the programme and in putting additional student support mechanisms in place. The situation hit rock bottom between …

Optimal Layout Of Multicast Groups Using Network Embedded Multicast Security In Ad Hoc Sensor Networks, Richard R. Brooks, Brijesh Pillai, Michele C. Weigle, Matthew Pirretti

Computer Science Faculty Publications

This paper considers the security of sensor network applications. Our approach creates multicast regions that use symmetric key cryptography for communications. Each multicast region contains a single keyserver that is used to perform key management and maintain the integrity of a multicast region. Communications between two multicast regions is performed by nodes that belong to both regions. To ease the network management burden, it is desirable for the networks to self-organize into regions and dynamically select their keyservers. This paper shows how to determine the number of keyservers (k) to use and the size in the number of hops (h) …

Recasting Dilemma Zone Design As A Marginal Cost-Benefit Problem, Anuj Sharma, Darcy M. Bullock, Srinivas Peeta

Department of Civil and Environmental Engineering: Faculty Publications

One control objective at high-speed isolated intersections is to provide safe phase transition by minimizing the occurrence of high-speed vehicles in the dilemma zone before the phase is terminated. An upper limit for extending the green (maximum green time) is used to avoid an indefinite extension of the main-street green. Currently, the maximum green times are chosen by using engineering judgment. This approach does not explicitly consider the trade-offs between safety and delay and hence often results in both unsafe and inefficient performance at the intersection under medium to heavy traffic volumes. The dilemma problem is recast as one of …

A Proportional-Integrator Type Adaptive Critic Design-Based Neurocontroller For A Static Compensator In A Multimachine Power System, Salman Mohagheghi, Ganesh K. Venayagamoorthy, Yamille Del Valle, Ronald G. Harley

Electrical and Computer Engineering Faculty Research & Creative Works

A novel nonlinear optimal controller for a static compensator (STATCOM) connected to a power system, using artificial neural networks, is presented in this paper. The action dependent heuristic dynamic programming, a member of the adaptive critic designs family is used for the design of the STATCOM neurocontroller. This neurocontroller provides optimal control based on reinforcement learning and approximate dynamic programming. Using a proportional-integrator approach, the proposed neurocontroller is capable of dealing with actual rather than deviation signals. Simulation results are provided to show that the proposed controller outperforms a conventional PI controller for a STATCOM in a small and large …

Optimal Wide Area Controller And State Predictor For A Power System, Salman Mohagheghi, Ganesh K. Venayagamoorthy, Ronald G. Harley

Electrical and Computer Engineering Faculty Research & Creative Works

An optimal wide area controller is designed in this paper for a 12-bus power system together with a Static Compensator (STATCOM). The controller provides auxiliary reference signals for the automatic voltage regulators (AVR) of the generators as well as the line voltage controller of the STATCOM in such a way that it improves the damping of the rotor speed deviations of the synchronous machines. Adaptive critic designs theory is used to implement the controller and enable it to provide nonlinear optimal control over the infinite horizon time of the problem and at different operating conditions of the power system. Simulation …

Effects Of Moisture On Ignition Behavior Of Moist California Chaparral And Utah Leaves, Thomas H. Fletcher, Brent M. Pickett, Steven G. Smith, Gregory S. Spittle, Megan M. Woodhouse, Elizabeth Haake, David R. Weise

Faculty Publications

Individual cuttings from eight plant species native to California chaparral or Utah were burned in a well-controlled, well-instrumented facility. Gas temperatures above a flat-flame burner were controlled at 987 C and 10 mol% O₂, resulting in a heat flux at the leaf surface varying from 80–140 kW/m². High moisture leaves were observed to burst due to the rapid escape of vapor from the leaf interior. Bubbles in or on the leaf surface were observed for leaves with moderate moisture contents. A large number of leaf temperature measurements were made, along with measurements of the ignition time …

Comparison Of Nonuniform Optimal Quantizer Designs For Speech Coding With Adaptive Critics And Particle Swarm, Ganesh K. Venayagamoorthy, Wenwei Zha

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents the design of a companding nonuniform optimal scalar quantizer for speech coding. The quantizer is designed using two neural networks to perform the nonlinear transformation. These neural networks are used in the front and back ends of a uniform quantizer. Two approaches are presented in this paper namely adaptive critic designs and particle swarm optimization, aiming to maximize the signal-to-noise ratio. The comparison of these optimal quantizer designs over a bit-rate range of 3-6 is presented. The perceptual quality of the coding is evaluated by the International Telecommunication Union's Perceptual Evaluation of Speech Quality standard

Development And Implementation Of The Bring Your Own Water Treatment System In Dense, Rural, And Mountainous Rwandan Communities, Maximilian Gold, Evan A. Thomas, Richard L. Byyny, Jean Pierre Habanabakize

Mechanical and Materials Engineering Faculty Publications and Presentations

Over a billion people in the world lack access to safe drinking water1. While numerous technological, medical, and educational solutions have been implemented for the benefit of disadvantaged communities, there is no 'magic bullet'. Instead, development agencies must partner directly with these communities to address their public health needs through appropriate technology solutions, backed up by education and assessment. The "Bring Your Own Water (BYOW) Treatment System" developed by the Engineers Without Borders-USA chapters at the University of Colorado at Boulder Chapter (EWB-CU) and the Johnson Space Center (EWB-JSC) is uniquely designed to address the water treatment requirements of two …

Optimal Neuro-Fuzzy External Controller For A Statcom In The 12-Bus Benchmark Power System, Salman Mohagheghi, Ganesh K. Venayagamoorthy, Ronald G. Harley

Electrical and Computer Engineering Faculty Research & Creative Works

An optimal neuro-fuzzy external controller is designed in this paper for a static compensator (STATCOM) in the 12-bus benchmark power system. The controller provides an auxiliary reference signal for the STATCOM in such a way that it improves the damping of the rotor speed deviations of its neighboring generators. A Mamdani fuzzy rule base constitutes the core of the controller. A heuristic dynamic programming-based approach is used to further train the controller and enable it to provide nonlinear optimal control at different operating conditions of the power system. Simulation results are provided that indicate the proposed neuro-fuzzy external controller is …