Engineering Commons^™

The Performance Of Irish Grown Timber Composites Under Fire Conditions, Cillian Murphy

Theses

In comparison with many European countries Ireland does not make the most effective use of its native timber. It is good economic and environmental practice to promote the more efficient utilization of this natural resource. In recent years there has been a revival in the use of timber in multi-storey construction which predominantly utilises load bearing exposed timber composite members. These timber composites are typically manufactured in Europe using European timber.

The current study investigates the viability of using Irish grown timber composites as a direct replacement in these load bearing members. The main areas of focus will be the …

Voltage Rise Mitigation In A Weak Distribution Network Due To The Impact Of Distributed Generation, Donal Caples

Theses

There are numerous aspects of a distribution network that must be studied in order to determine the maximum size of distributed generation that can be accommodated on the distribution network before supply standards are breached. Voltage rise is one of the main aspects of concern when connecting a distributed generator to a distribution network and this thesis develops the understanding of this phenomenon and concludes with a real life study.

Mathematical and computer simulation software examples within this thesis demonstrate how voltage rise can be reduced to the maximum allowable limit, a major concern if the capacity of a distributed …

An Analysis Of Dredge Material Reuse Techniques For Ireland, Colm Sheehan

Theses

This thesis examines the use and applicability of a range of dredge material management techniques for the Republic of Ireland which will ultimately assist the stakeholders in the industry in assessing the available dredge material management options. A detailed study is presented into the critical parameters required for successful implementation of a range of dredge material management options. An overview of the Irish dredging industry including current dredge material management practice is presented. This is complemented by a detailed critical analysis of the industry which identifies areas requiring development and future challenges for the dredging industry in Ireland. To further …

A Study Of Creep And Shrinkage In Concrete With A Consideration Of Its Effects On Curved Post-Tensioned Concrete Bridges, William O'Sullivan

Theses

The first objective of the project was to explore the differences between Ordinary Portland Cement (OPC) and Ground Granulated Blast-Furnace Slag (GGBS) cement. The use of GGBS cement concrete is increasing in industry due to the environmental and durability benefits it gives compared with OPC concrete. Data on the creep properties of GGBS cement concrete is limited compared with the data that is available for OPC concrete. Laboratory testing was undertaken to determine the different effects of creep on OPC concrete and GGBS concrete.

The second project objective was to research the effects of creep on post - tensioned curved …

Graphical Image Classification Combining An Evolutionary Algorithm And Binary Particle Swarm Optimization, Beibei Cheng, Renzhong Wang, Sameer K. Antani, R. Joe Stanley, George R. Thoma

Electrical and Computer Engineering Faculty Research & Creative Works

Biomedical journal articles contain a variety of image types that can be broadly classified into two categories: regular images, and graphical images. Graphical images can be further classified into four classes: diagrams, statistical figures, flow charts, and tables. Automatic figure type identification is an important step toward improved multimodal (text + image) information retrieval and clinical decision support applications. This paper describes a feature-based learning approach to automatically identify these four graphical figure types. We apply Evolutionary Algorithm (EA), Binary Particle Swarm Optimization (BPSO) and a hybrid of EA and BPSO (EABPSO) methods to select an optimal subset of extracted …

Approximate Policy Iteration For Markov Control Revisited, Abhijit Gosavi

Engineering Management and Systems Engineering Faculty Research & Creative Works

Q-Learning is based on value iteration and remains the most popular choice for solving Markov Decision Problems (MDPs) via reinforcement learning (RL), where the goal is to bypass the transition probabilities of the MDP. Approximate policy iteration (API) is another RL technique, not as widely used as Q-Learning, based on modified policy iteration. in this paper, we present and analyze an API algorithm for discounted reward based on (i) classical temporal differences update for policy evaluation and (ii) simulation-Based mean estimation for policy improvement. Further, we analyze for convergence API algorithms based on Q-factors for (i) discounted reward and (ii) …

Preface To Part Iii: Model Based Systems Engineering, Steven Corns

Engineering Management and Systems Engineering Faculty Research & Creative Works

No abstract provided.

Enabling Systems And The Adaptability Of Complex Systems-Of-Systems, Charles O. Adler, Cihan H. Dagli

Engineering Management and Systems Engineering Faculty Research & Creative Works

For complex techno-social system-of-systems, the system's robustness and its ability to adapt to changing environments and circumstances over the life cycle of the systems is an important measure of system quality and effectiveness. the IEEE 15288-2004 standard describes the concept of "enabling systems" that provide non-operational services to the system-of-interest at various times in the system life cycle. This concept of enabling systems provides critical components and perspective in the architecting and analysis of systems-of-systems adaptability and capabilities over time. Enabling systems also provide a potential strong link between the technical system and larger environmental effects such as economic conditions. …

Computational System Architecture Development Using A Holistic Modeling Approach, Renzhong Wang, Cihan H. Dagli

Engineering Management and Systems Engineering Faculty Research & Creative Works

This paper presents an innovative system architecture development framework that allows the search of optimum architecture solutions within large design space by automating certain model construction, alternative generation, simulation, and assessment tasks. Such framework is facilitated by a holistic modeling approach that combines the capabilities of Object Process Methodology (OPM), Colored Petri Net (CPN) and feature model. the resultant holistic model not only can capture the structural, behavior, and dynamic aspects of a system, allowing strong analysis methods to be applied, but also can specify the architectural design space allowing generation of architecture alternatives that cover it. the proposed framework …

Application Of Model-Based Systems Engineering On A University Satellite Design Team, Dustin Nottage, Steven Corns

Engineering Management and Systems Engineering Faculty Research & Creative Works

System Engineering is a foundation of the Missouri S&T's Satellite Design Team, although it is not explicitly stated at all times. However, implementation of the systems engineering process within a student design team presents unique challenges. Student design teams have a high personnel turnover, a limited time commitment due to classes, some new members have little to no experience, and a sometimes lack of motivation to participate since it is volunteered time. the largest problem on the team is getting the new members knowledgeable about the system so they can start contributing as fast as possible. the other big problem …

Eustressed Or Distressed? Combining Physiology With Observation In User Studies, Avinash Wesley, Peggy Lindner, Ioannis Pavlidis

Engineering Management and Systems Engineering Faculty Research & Creative Works

In this article the authors describe a novel way to conduct user studies via the combination of a physiological and an observational information channel. The method enables not only the quantification of arousing emotional states but also their disambiguation into positive or negative instances. The physiological channel targets sympathetic responses and has materialized as a perspiratory signal extracted from thermal imagery of the perinasal area. The observational channel has materialized via decoding of facial expressions. However, while such decoding is usually performed in the visible spectrum, the authors have developed an algorithm to carry this out in thermal imagery instead. …

Protocols For Highly-Dynamic Airborne Networks, Egemen K. Çetinkaya, Justin P. Rohrer, Abdul Jabbar, Mohammed J. F. Alenazi, Dongsheng Zhang, Dan S. Broyles, Kamakshi Sirisha Pathapati, Hemanth Narra, Kevin Peters, Santosh Ajith Gogi, James P. G. Sterbenz

Electrical and Computer Engineering Faculty Research & Creative Works

End-to-end communication in highly-dynamic airborne networks is challenging due to the presence of highly mobile nodes and the inherent nature of wireless communication channels. Domain-specific protocols are required that can address these challenges and enable reliable transmission of data in this environment. We develop the ANTP (airborne network and transport protocols) suite that operates in this highly-dynamic environment while utilising cross-layer optimisations between the physical, MAC, network, and transport layers. We show how each component in the ANTP suite outperforms the traditional TCP/IP and MANET protocols through simulation using ns-3. Having verified these protocols through simulation and analysis, the next …

Equivalent Circuit Model Of Coaxial Probes For Patch Antennas, Y. S. Hu, Yanzhi Zhang, Jun Fan

Mathematics and Statistics Faculty Research & Creative Works

An equivalent circuit model of coaxial probes is derived directly from the intrinsic via circuit model. as all the higher-order evanescent modes have been included analytically in the parasitic circuit elements, only the propagating mode needs to be considered by the simplest uniform-current model of a coaxial probe in numerical solvers such as -nite element method (FEM) or -nite divergence time domain (FDTD). This avoids dense meshes or sub-gridding techniques and greatly reduces the computational efforts for accurate calculation of the probe input impedance. the derived equivalent circuit model and the new feeding technique have been validated by both analytical …

The Far Field Transformation For The Antenna Modeling Based On Spherical Electric Field Measurements, P. Li, Lijun Jiang

Electrical and Computer Engineering Faculty Research & Creative Works

According to the uniqueness theorem, the far field radiation pattern of radiators such as antennas can be determined from the measured tangential electric or magnetic field components over an arbitrary Huygens' surface enclosing the radiator. In this paper, a method using the spherical electric field measurement is developed to calculate the far field radiation. Following the Schelkunoff's field equivalence principle, a spherical region surrounding the radiator is assumed and its internal space is filled up with the perfect electric conductor (PEC). The radiated field from the Huygens' equivalent electric current is zero. Referring to the Ohm-Rayleigh method and the scattering …

An Efficient Method For Computing Highly Oscillatory Physical Optics Integral, Y. M. Wu, Lijun Jiang, W. C. Chew

Electrical and Computer Engineering Faculty Research & Creative Works

In this work, we use the numerical steepest descent path (numerical SDP) method in complex analysis theory to calculate the highly oscillatory physical optics (PO) integral with quadratic phase and amplitude variations on the triangular patch. The Stokes' phenomenon will occur due to various asymptotic behaviors on different domains. The stationary phase point contributions are carefully studied by the numerical SDP method and complex analysis using contour deformation. Its result agrees very well with the leading terms of the traditional asymptotic expansion. Furthermore, the resonance points and vertex points contributions from the PO integral are also extracted. Compared with traditional …

Electronic Musical Instrument To Generate Musical Tones To Imitate A Stringed Instrument, M. Nakagawa, Shun Takai, Shun Takai

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Provided are an electronic musical instrument, computer Storage device, and method for generating tone. A sound source in an electronic musical instrument generates a first tone at a first pitch in response to a first tone generation instruction received by an input device of the electronic musical instrument. A second tone generation instruction is received to generate a second tone at a second pitch while generating the first tone at the sound source. A determination is made of a pitch difference of the first and the second pitches. The sound source is controlled to generate the second tone and to …

Optimization In Energy And Power Management For Renewable-Diesel Microgrids Using Dynamic Programming Algorithm, Tu A. Nguyen, Mariesa L. Crow

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents an optimization analysis for energy and power management in microgrids with renewable energy resources and diesel generators. Dynamic Programming (DP) algorithm and the simplex method have been used to minimize the total daily cost of the system and also maximize the total efficiency of the energy storage system during charge and discharge. the algorithm is validated on a hybrid system for military forward operating base camps that contain a PV array, wind generator, hydrogen-Based fuel cell, batteries and diesel generators. © 2012 IEEE.

Adjusting A Level At Which To Generate A New Tone With A Current Generated Tone, M. Nakagawa, Shun Takai

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Provided are a tone control device and a method for adjusting a volume level at which to generate a new tone and at least one current tone according to a target volume level and a current volume level. A note-on event associated with a received volume level is received from an input device. A current volume level is processed to determine a new volume level in response to receiving the note-on event while generating at least one current tone at the current volume level. The at least one current tone and a new tone associated with the received note-on event …

Electronic Musical Instrument, M. Nakagawa, Shun Takai

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Provided are an electronic musical instrument, computer storage device, and method generating tones for held notes. Indication is made of held notes having pitches as held in response to receiving note-on information for the held notes from an input device of an electronic musical instrument while receiving hold information from a hold device of the electronic musical instrument. Note-on information is received for a received note having a pitch while generating the pitches for the held notes. Selection is made of one of the held notes to release according to a first selection criteria in response to determining that the …

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

Electrical & Computer Engineering and Computer Science Faculty Publications

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 iOS device, then …

Design Of Metallic Bipolar Plates For Pem Fuel Cells, Sriram Praneeth Isanaka, Austin Das, Frank W. Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

This project focused on the design and production of metallic bipolar plates for use in PEM fuel cells. Different metals were explored and stainless steel was found out to be best suited to our purpose. Following the selection of metal, it was calculated that to produce 0.7 W of power, the bipolar plate should have an active surface of 25cm2. The bipolar plates were designed with different flow field patterns and manufactured. Different flow field patterns that were used were the straight design, serpentine, multiple serpentine, pintype, interdigitated design and other custom designs. These plates were then assembled along with …

Improving The Efficiency Of Turbocharged Spark Ignition Engines For Passenger Cars Through Waste Heat Recovery, Alberto A. Boretti

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The turbocharged direct injection stoichiometric spark ignition gasoline engine has less than Diesel full load brake engine thermal efficiencies and much larger than Diesel penalties in brake engine thermal efficiencies reducing the load by throttling. This engine has however a much better power density, and therefore may operate at much higher BMEP values over driving cycles reducing the fuel economy penalty of the vehicle. This engine also has the advantage of the very well developed three-way catalytic converter after treatment to meet future emission regulations. in these engines the efficiency may be improved recovering the waste heat, but this recovery …

Kers Braking For 2014 F1 Cars, Alberto A. Boretti

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Small, high power density turbocharged engines coupled to kinetic energy recovery systems are one of the key areas of development for both passenger and racing cars. in passenger cars, the KERS may reduce the amount of thermal energy needed to reaccelerate the car following a deceleration recovering part of the braking energy. This translates in a first, significant fuel energy saving. Also considering the KERS torque boost increasing the total torque available to accelerate the car, large engines working at very low brake mean effective pressures and efficiencies over driving cycles may also be replaced by small higher power density …

Simulation And Testing Of Polymer Electrolyte Membrane Fuel Cell Bipolar Plates Fabricated By Selective Laser Sintering, M. Wu, Ming-Chuan Leu, N. Guo

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Polymer Electrolyte Membrane (PEM) fuel cell converts directly electrochemical energy into electricity. Flow channels in bipolar plates, a critical component of fuel cell, were designed, simulated and tested. the bipolar plate used a mixture of graphite materials and was fabricated using a Selective Laser Sintering (SLS) process. the fabricated green parts were carbonized at high temperatures and converted into brown parts. Infiltration of resin was used to enhance the electric conductivity and strength of the bipolar plate. Finite element simulations were performed to investigate the state of species (hydrogen, oxygen) in the channels and Gas Diffusion Layers (GDLs) for four …

A Modified Fixed Sphere Decoding Algorithm For Under-Determined Mimo Systems, Chen Qian, Jingxian Wu, Yahong Rosa Zheng, Zhaocheng Wang

Electrical and Computer Engineering Faculty Research & Creative Works

A modified FSD algorithm is proposed for under-determined (UD) multiple-input multiple-output (MIMO) systems with N transmit antennas and M < N receive antennas. This paper focuses on the low-complexity detection of coded UD-MIMO systems with iterative turbo detection, where a soft-input soft-output (SISO) MIMO detector exchanges soft information with a SISO decoder. in the first iteration, a modified fixed complexity sphere decoding (FSD) method is developed by utilizing the structure of a UD-MIMO system. the modified FSD employs a new detection ordering scheme that has a lower complexity but a better performance compared to the conventional ordering scheme. from the second iteration and beyond, the MIMO detector is implemented with a generalized serial interference cancelation (GSIC) scheme and a block decision feedback equalizer (BDFE) to further reduce the complexity. Simulation results show that the newly proposed FSD-GSIC-BDFE structure can achieve significant performance gains over existing schemes, especially for systems with high level modulations. © 2012 IEEE.

Cross-Layer Design Of Energy Efficient Coded Arq Systems, Gang Wang, Jingxian Wu, Yahong Zheng

Electrical and Computer Engineering Faculty Research & Creative Works

The energy efficient design of coded automatic-repeat-request (ARQ) systems is studied in this paper. the optimization aims to minimize the energy required for the successfully delivery of one information bit from a transmitter to a receiver. the design is performed by incorporating a wide range of practical system parameters and metrics, such as hardware power consumption, modulation, channel coding, and frame error rate (FER) in the physical layer, and frame length and protocol overhead in the media access control layer. a new log-domain threshold approximation method is proposed to analytically quantify the impacts of the various system parameters on the …

Optimal Adaptive Control Of Nonlinear Continuous-Time Systems In Strict Feedback Form With Unknown Internal Dynamics, H. Zargarzadeh, T. Dierks, S. Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

A novel approach is proposed for multi-input multi-output (MIMO) optimal adaptive control of nonlinear continuous-time systems in strict feedback form with uncertain internal dynamics. First, it is shown that the optimal adaptive tracking problem of strict feedback systems can be reduced to an optimal regulation problem of affine nonlinear continuous-time systems expressed as a function of tracking error by designing a properly chosen adaptive feedforward control input. Then, an optimal adaptive feedback scheme is introduced for the affine system to estimate the solution of the Hamilton-Jacobi-Bellman (HJB) equation online which becomes the optimal feedback control input for the closed-loop system. …

Examination Of The Nonlinear Dynamics Of A Chaotic Acousto-Optic Bragg Modulator With Feedback Under Signal Encryption And Decryption, Mohammed A. Al-Saedi, Monish Ranjan Chatterjee

Electrical and Computer Engineering Faculty Publications

An acousto-optic Bragg cell with first-order feedback, which exhibits chaotic behavior past the threshold for bistability, was recently examined for possible chaotic encryption and recovery of simple messages (such as low-amplitude periodic signals) applied via the bias input of the sound cell driver. We carry out a thorough examination of the nonlinear dynamics of the Bragg cell under intensity feedback for (i) dc variations of the feedback gain (β˜) and the phase shift parameter (α^ 0) and (ii) ac variations of α^ 0; total under signal encryption, investigating both from two different perspectives: (i) examining chaos in view of the …

Commentary And Interpretations Of Tagore’S 'Ode To Africa', Monish Ranjan Chatterjee

Electrical and Computer Engineering Faculty Publications

This is a commentary/interpretation of Rabindranath Tagore's poem "Ode to Africa."

Time Dynamics Of Self-Pumped Reflection Gratings In A Photorefractive Polymer, Partha P. Banerjee, S. H. Buller, C. M. Liebig, S. A. Basun, Gary Cook, Dean R. Evans, Pierre-Alexandre Blanche, J. Thomas, Cory W. Christenson, N. Peyghambarian

Electrical and Computer Engineering Faculty Publications

The time dynamics of self-pumped reflection gratings in a commonly used photorefractive polymer PDCST:PVK:ECZ-BBP:C60 with no additional electron sources or traps is investigated. While holes are normally the mobile charges and responsible for grating formation, our experimental observations, analyzed using multi-exponential fitting curves, show evidence of electrons in addition to holes as charge carriers, particularly above an applied field of 40 V/μm.

The dependence of effective carrier mobilities on the applied electric field, deduced from experimental results, show stronger field dependence of electron mobility at high electric fields. At an applied field of 70 V/μm, electron and hole mobilities become …