Engineering Commons^™

Thermal And Mechanical Properties Of Polyethylene-Polypropylene Blends, Rania Omar Akkad

Theses

The thermal and mechanical characteristics of thermally treated and untreated pure polyethylene (PE), pure polypropylene (PP) and their blends were investigated. Injection-moulded samples containing 100:00,75:25,50:50,25:75 and 00:100 weight percentage of PE:PP, were prepared and thermally treated at 100°C for 0, 2, 4, 7, 14 days. The treated samples were subjected to differential scanning calorimetry (DSC), thermogravimetry (TG & DTG), infrared spectral analysis (IR) and tensile tests in order to study the effect of thermal treatment and blending ratios on their thermal and mechanical properties. The results indicate that addition of PE causes the melting temperature (T_m) of PP …

Sonar Signal Enhancement Using Fractional Fourier Transform, Madalina Barbu, Edit J. Kaminsky, Russell E. Trahan

Electrical Engineering Faculty Publications

In this paper we present an approach for signal enhancement of sonar signals. Work reported is based on sonar data collected by the Volume Search Sonar (VSS), as well as VSS synthetic data. The Volume Search Sonar is a beamformed multibeam sonar system with 27 fore and 27 aft beams, covering almost the entire water volume (from above horizontal, through vertical, back to above horizontal). The processing of a data set of measurement in shallow water is performed using the Fractional Fourier Transform algorithm. The proposed technique will allow efficient determination of seafloor bottom characteristics and bottom type using the …

Chirp Slope Keying For Underwater Communications, Edit J. Kaminsky, Lastri Simanjuntak

Electrical Engineering Faculty Publications

This paper presents a novel broadband modulation method for digital underwater communications: Chirp Slope Keying (CSK). In its simplest form, the binary information modulates the slope of a linear chirp, with up-chirps representing ones and down-chirps representing zeros. Performance evaluation in the form of probability of error vs. SNR show that the system performs as expected for AWGN environments and very well for more realistic models for underwater acoustical communications, such as the Raylegih channel with Doppler, delays, phase offset, and multipath.

Blind Phase Recovery In Cross Qam Communication Systems With The Reduced Constellation Eigth-Order Estimator (Rceoe), Kenneth V. Cartwright, Edit J. Kaminsky

Electrical Engineering Faculty Publications

The eighth-order (EOE) phase estimator [4] is modified to work for an eight-symbol symmetrical constellation, so that the large signal-to-noise (SNR) performance is not limited by self-noise. By using only the eight highest energy points of cross- QAM constellations, a reduced constellation eighth-order estimator (RCEOE) is proposed. Computer simulations for 128-QAM show that this new method performs substantially better than the recently introduced APP phase estimator of Wang et al. [8]. However, simulations with 32-QAM show little performance advantage of the RCEOE over the APP estimator, for SNR values normally of interest, whereas for low SNR, the improvement is significant. …

An Optimum Hardware Detector For Constant Envelope Quadrature-Quadrature Phase Shift Keying (Ceq2osk), Kenneth V. Cartwright, Edit J. Kaminsky

Electrical Engineering Faculty Publications

A hardware detector for constant envelope quadrature- quadrature phase-shift keying (CEQ2PSK) is proposed. It uses appropriate hard decisions; yet, it achieves optimum probability of bit error performance, unlike the suboptimum detector of Saha and Birdsall. This optimum performance is verified through Monte Carlo computer simulations. Additionally, a more correct expression is given for the probability of bit error performance for CEQ2PSK, which gives the gain over nonconstant Q2PSK as 1.44 dB, rather than the previously published value of 1.76 dB.

Asymptotic Performance Of The Pth Power-Law Phase Estimator, Kenneth V. Cartwright, Edit J. Kaminsky

Electrical Engineering Faculty Publications

An expression for the true variance of the Pth powerlaw phase estimator, as the number of samples approaches infinity, is given. This expression is an extension to the linear approximation of Moeneclaey and de Jonghe [1] which is known to be inadequate in some practical systems. Our new expression covers general 2π/P-rotationally symmetric constellations that include those of PAM, QAM, PSK, Star M-QAM, MR-DPSK, and others. This expression also generalizes the known expressions for QAM and PSK. Additionally, our expression reduces to the Cramer-Rao bound given by Steendam and Moeneclaey [9], as SNR goes to zero. Monte Carlo simulations provide …

Organizing A K-12 Ai Curriculum Using Philosophy Of The Mind, Glenn W. Ellis, Eleanor C. Ory, Nalini Bhushan

Engineering: Faculty Publications

High school teams competing in the FIRST Robotics Competition and students of all ages building Lego robots have become increasingly common in K-12 education. Although robotics can be an excellent means to introduce technology and engineering design into the classroom, the scope of artificial intelligence (AI) is much greater. To help students learn about these topics in a meaningful way and to see how they fit together, this paper presents a concept map that uses principles from philosophy of the mind to organize AI topics. This approach supports a deeper understanding of AI, while making philosophical issues that interest teenagers …

To Pop Or Not To Pop: Elementary Teachers Explore Engineering Design With Pop-Up Books, Susan Etheredge, Catherine Lewis, Glenn Ellis, Thomas Gralinski

Engineering: Faculty Publications

Elementary teachers explore engineering design with pop-up books, during a two-week professional development summer institute, held at a four-year liberal arts college in northeastern United States. The descriptions and examples of pedagogical methods, models, and materials used to engage the teachers in paper engineering through their immersion into the world of pop-up books, are included. Pedagogical strategies and project-based curriculum design of the institute reflect 'best practices' as informed by current cognitive science literature on teaching and learning are discussed. Social-collaborative context during the summer institute that would guide and support teachers' developing understandings and skills in engineering education is …

Effects Of A Smaller Unit Cell Planar Ebg Structure On The Mutual Coupling Of A Printed Dipole Array, M. Faisal Abedin, Mohammod Ali

Faculty Publications

A new smaller unit-cell planar electromagnetic bandgap (EBG) structure is proposed on low dielectric constant low-cost substrate (TMM: epsilon(r) = 4.5, thickness = 25 mils) that has a stopband frequency at around 4 GHz. The proposed structure when placed in between a two-element printed dipole array results in over 13-dB reduction in mutual coupling and a significant improvement in antenna return loss bandwidth and gain pattern.

Flexible Multiobjective Control Of Power Converter In Active Hybrid Fuel Cell/Battery Power Sources, Zhenhua Jiang, Lijun Gao, Roger A. Dougal

Faculty Publications

Hybrid power sources composed of fuel cells and secondary batteries can combine the high energy density of fuel cells with the high power density of batteries. A dc/dc power converter can be placed between the fuel cell and the battery to balance the power flow and greatly augment the peak output power. This paper presents a novel, flexible strategy for multiobjective control of the power converter in the hybrid power source. The control strategy is able to regulate the output current of the fuel cell and the charging current or voltage of the battery while limiting the discharging current of …

Crystal Growth, Characterization And Anisotropic Electrical Properties Of Gase Single Crystals For Thz Source And Radiation Detector Applications, K. C. Mandal, C. Noblitt, M. Choi, A. Smirnov, R. D. Rauh

Faculty Publications

The single crystal growth of large semi‐insulating GaSe by the vertical Bridgman technique using zone‐refined selenium (Se) and HP gallium (Ga) is described. The grown crystals (up to 10 cm long and 2.5 cm diameter) have been characterized thoroughly by X‐ray diffraction (XRD), energy dispersive analysis by x‐rays (EDAX), optical absorption/transmission, X‐ray photoelectron spectroscopy (XPS), charge carrier electrical property measurements, second harmonic test, and radiation detection measurements.

Study And Design Of An Intelligent Preconditioner Recommendation System, Shuting Xu

University of Kentucky Doctoral Dissertations

There are many scientific applications in which there is a need to solve very large linear systems. The preconditioned Krylove subspace methods are considered the preferred methods in this field. The preconditioners employed in the preconditioned iterative solvers usually determine the overall convergence rate. However, choosing a good preconditioner for a specific sparse linear system arising from a particular application is the combination of art and science, and presents a formidable challenge for many design engineers and application scientists who do not have much knowledge of preconditioned iterative methods.

We tackled the problem of choosing suitable preconditioners for particular applications …

Effects Of Aging On The Biomechanics Of Slips And Falls, Thurmon E. Lockhart, James L. Smith, Jeffrey C. Woldstad

Department of Industrial and Management Systems Engineering: Faculty Publications

Although much has been learned in recent decades about the deterioration of muscular strength, gait adaptations, and sensory degradation among older adults, little is known about how these intrinsic changes affect biomechanical parameters associated with slip-induced fall accidents. In general, the objective of this laboratory study was to investigate the process of initiation, detection, and recovery of inadvertent slips and falls. We examined the initiation of and recovery from foot slips among three age groups utilizing biomechanical parameters, muscle strength, and sensory measurements. Forty-two young, middle-age, and older participants walked around a walking track at a comfortable pace. Slippery floor …

Details And Description Of Industrial Engineering, Paul Savory

Department of Industrial and Management Systems Engineering: Faculty Publications

This content paper addresses key questions for students interested in pursuing industrial engineering as an academic major: What is industrial engineering? What personality characteristics do Industrial Engineers have? What types of projects do Industrial Engineers work on? What types of jobs do Industrial Engineers have? Where do Industrial Engineers work once they graduate? How much can Industrial Engineers earn? I have never heard of IE, is it a new area? How do Industrial Engineers benefit society and business? What classes will I take as an industrial engineering student? What are examples of problems I will learn how to solve? Are …

Editorial, Robert W. Stewart, Michael W. Hoffman, Stephan Weiss

Department of Electrical and Computer Engineering: Faculty Publications

In the past years, digital signal processing (DSP) algorithms and architectures for baseband communication systems have fuelled the delivery of applications such as 3G mobile communications and wireless LAN to mass markets. This was made possible by a tremendous growth in the performance of computational devices such as digital signal processors and FPGAs, as well as an increase in sampling rates of conversion devices to potentially several 100 MHz. While the development of both computational devices and ADCs/DACs continues, thus permitting DSP to be applied at IF sampling rates and possibly beyond, the opportunities for further enhancing radio devices by …

Comparison Of Antenna Array Systems Using Ofdm For Software Radio Via The Sibic Model, Khoi D. Le, Michael W. Hoffman, Robert D. Palmer

Department of Electrical and Computer Engineering: Faculty Publications

This paper investigates the performance of two candidates for software radio WLAN, reconfigurable OFDM modulation and antenna diversity, in an indoor environment. The scenario considered is a 20m × 10m × 3m room with two base units and one mobile unit. The two base units use omnidirectional antennas to transmit and the mobile unit uses either a single antenna with equalizer, a fixed beamformer with equalizer, or an adaptive beamformer with equalizer to receive. The modulation constellation of the data is QPSK and 16-QAM. The response of the channel at the mobile unit is simulated using a three-dimensional indoor WLAN …

A Novel Role For Gadd45Β As A Mediator Of Mmp-13 Gene Expression During Chondrocyte Terminal Differentiation, Kosei Ijiri, Luiz F. Zerbini, Haibing Peng, Ricardo G. Correa, Binfeng Lu, Nicole Walsh, Yani Zhao, Noboru Taniguchi, Xu-Ling Huang, Hasan H. Otu, Hong Wang, Jian Fei Wang, Setsuro Komiya, Patricia Ducy, Mahboob U. Rahman, Richard A. Flavell, Ellen M. Gravallese, Peter Oettgen, Towia A. Libermann, Mary B. Goldring

Department of Electrical and Computer Engineering: Faculty Publications

The growth arrest and DNA damage-inducible 45β (GADD45β) gene product has been implicated in the stress response, cell cycle arrest, and apoptosis. Here we demonstrated the unexpected expression of GADD45β in the embryonic growth plate and uncovered its novel role as an essential mediator of matrix metalloproteinase-13 (MMP-13) expression during terminal chondrocyte differentiation. We identified GADD45β as a prominent early response gene induced by bone morphogenetic protein-2 (BMP-2) through a Smad1/Runx2-dependent pathway. Because this pathway is involved in skeletal development, we examined mouse embryonic growth plates, and we observed expression of Gadd45β mRNA coincident with Runx2 protein …

Range Imaging Observations Of Pmse Using The Eiscat Vhf Radar: Phase Calibration And First Results, J. R. Fernandez, R. D. Palmer, P. B. Chilson, I. Haggstrom, M. T. Rietveld

Department of Electrical and Computer Engineering: Faculty Publications

A novel phase calibration technique for use with the multiple-frequency Range IMaging (RIM) technique is introduced based on genetic algorithms. The method is used on data collected with the European Incoherent SCATter (EISCAT) VHF radar during a 2002 experiment with the goal of characterizing the vertical structure of Polar Mesosphere Summer Echoes (PMSE) over northern Norway. For typical Doppler measurements, the initial phases of the transmitter and receiver are not required to be the same. The EISCAT receiver systems exploit this fact, allowing a multistatic configuration. However, the RIM method relies on the small phase differences between closely spaced frequencies. …

Phased-Array Design For Biological Clutter Rejection: Simulation And Experimental Validation, B.L. Cheong, Michael Hoffman, R.D. Palmer, Stephen J. Frasier, F.J. Lopez-Dekker

Department of Electrical and Computer Engineering: Faculty Publications

This paper highlights recent results obtained with the Turbulent Eddy Profiler (TEP), which was devel- oped by the University of Massachusetts. This unique 915-MHz radar has up to 64 spatially separated receiving elements, each with an independent receiver. The calibrated raw data provided by this array could be processed using sophisticated imaging algorithms to resolve the horizontal structures within each range gate. After collecting all of the closely spaced horizontal slices, the TEP radar can produce three- dimensional images of echo power, radial velocity, and spectral width. From the radial velocity measure- ments, it is possible to estimate the three-dimensional …

On The Performance Of Turbo Codes With Convolutional Interleavers, Sina Vafi, Tadeusz Wysocki

Department of Electrical and Computer Engineering: Faculty Publications (to 2015)

In this paper, some issues governing the block-wise performance of convolutional interleavers used in turbo codes are presented. Two different constructions of convolutional interleaver differing by the position of stuff bits in the interleaved data block are considered here. The performance assessment is based on the contribution of each weight to the overall code performance. For the given turbo code and each utilized interleaver, weight contribution is computed to finalize the code behavior in different signal to noise ratios. Simulations have been performed to verify the conducted analysis.

Combined Asterism And Sphere Decoder For Large Asymmetric Mimo Systems, Phillip Conder, Tadeusz Wysocki

Department of Electrical and Computer Engineering: Faculty Publications (to 2015)

The area of Multiple Input Multiple Output (MIMO) communications systems has received enormous attention recently as they can provide a roughly linear increase in data rate by using Multiple Transmit and Receive antennas. The optimal detection strategy for a MIMO receiver is to perform a Maximum-Likelihood (ML) search over all possible transmitted symbol combinations which has an exponential complexity when the constellation size of number of transmit antennas increase. Sphere and Asterism decoders are schemes that achieved ML performance for MIMO systems, but both have shortcomings in computational complexity, Sphere decoding when n_t > n_r and Asterism when n …

A Generalized Algorithm For The Generation Of Correlated Rayleigh Fading Envelopes In Radio Channels, Le Chung Tran, Tadeusz Wysocki, Jennifer Seberry, Alfred Mertins

Department of Electrical and Computer Engineering: Faculty Publications (to 2015)

Although generation of correlated Rayleigh fading envelopes has been intensively considered in the literature, all conventional methods have their own shortcomings, which seriously impede their applicability. In this paper, a very general, straightforward algorithm for generation of an arbitrary number of Rayleigh envelopes with any desired, equal or unequal power, in wireless channels either with or without Doppler frequency shifts, is proposed. The proposed algorithm can be applied in case of spatial correlation, such as with antenna arrays in Multiple Input Multiple Output (MIMO) systems, or spectral correlation between the random processes like in Orthogonal Frequency Division Multiplexing (OFDM) systems. …

Generalized Williamson And Wallis-Whiteman Constructions For Improved Square Order-8 Cois Stbc, Le Chung Tran, Tadeusz Wysocki, Jennifer Seberry, Alfred Mertins, Sarah A. Spence

Department of Electrical and Computer Engineering: Faculty Publications (to 2015)

Constructions of square, maximum rate Complex Orthogonal Space-Time Block Codes (CO STBCs) are well known, however codes constructed via the known methods include numerous zeros, which impede their practical implementation. By modifying the Williamson and Wallis-Whiteman arrays to apply to complex matrices, we propose two methods of construction of square, order-4n CO STBCs from square, order-n codes which satisfy certain properties. Applying the proposed methods, we construct square, maximum rate, order-8 CO STBCs with no zeros, such that the transmitted symbols equally disperse through transmit antennas. Those codes, referred to as the improved square …

Asterism Decoding For Turbo Coded Mimo Systems, Phillip Conder, Tadeusz Wysocki

Department of Electrical and Computer Engineering: Faculty Publications (to 2015)

The area of Multiple Input Multiple Output (MIMO) communications systems has received enormous attention recently as they can provide a roughly linear increase in data rate by using multiple transmit and receive antennas. MIMO combined with an Turbo coding has been shown as a promising way to achieve near capacity for wireless channels.
Where previously described decoders provide linear decoding where the number of receive antennas is at least equal to the number of transmit antennas, are computationally burdensome when n_t > n_r. Asterism decoding is a scheme that achieved ML performance for MIMO systems for any number …

Colossal Dielectric And Electromechanical Responses In Self Assembled Polymeric Nanocomposites, Cheng Huang, Q. M. Zhang, Jiang Yu Li, Manese Rabeony

Department of Engineering Mechanics: Faculty Publications

An electroactive polymer nanocomposite, in which high dielectric constant copper phthalocyanine oligomer (o-CuPc) nanoparticles are incorporated into the block polyurethane (PU) matrix by the combination of “top down” and “bottom up” approaches, was realized. Such an approach enables the nanocomposite to exhibit colossal dielectric and electromechanical responses with very low volume fraction of the high dielectric constant o-CuPc nanofillers (~3.5%) in the composite. In contrast, a simple blend of o-CuPc and PU composite with much higher o-CuPc content (~16% of o-CuPc) shows much lower dielectric and electromechanical responses.

A Model For Predicting The Evolution Of Damage In Viscoelastic Particle-Reinforced Composites, G. D. Seidel, D. H. Allen, K. L. E. Helms, S. E. Groves

Department of Engineering Mechanics: Faculty Publications

A viscoelastic cohesive zone model is employed within the framework of a finite element code to analyze a two-phase viscoelastic particle-reinforced composite material consisting of a relatively stiff aggregate embedded in a copolymer binder. The composite of interest, LX17, is noted to have a very large aggregate volume fraction and as such, aggregate grain boundaries were generated within finite element meshes along which viscoelastic cohesive zones have been embedded to model the binder. It has been observed experimentally that the majority of damage in LX17 occurs within the binder, and thus, a damage evolution law has been applied to the …

Influence Of Composition And Heat-Treatment On The Charge Transport Properties Of Poly(3-Hexylthiophene) And [6,6]-Phenyl C61-Butyric Acid Methyl Ester Blends, Jinsong Huang, Gang Li, Yang Yang

Department of Mechanical and Materials Engineering: Faculty Publications

Poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl C₆₁-butyric acid methyl ester (PCBM) blends have been demonstrated to form highly efficient polymer photovoltaic devices. In this letter, the time-of-flight technique is used to investigate the influence of composition and heat treatment on charge transport properties of P3HT and PCBM blends. The transport of electrons and holes both display a transition from dispersive to nondispersive and return to dispersive again as the percentage of PCBM increases. A balanced mobility of both electron and hole is obtained at a composition of 1:1 weight ratio, and it is nearly independent of the electrical field in …

Biological Opinion On The Operation Of The Missouri River Main Stem System, Missouri River Bank Stabilization And Navigation Project, And Operation Of The Kansas River Reservoir System

United States Army Corps of Engineers, Omaha District

The U.S. Army Corps of Engineers (Corps) prepares an annual report for interested parties in accordance with reporting requirements of the "Biological Opinion (BiOp) on the Operation of the Missouri River Main Stem System, Operation and Maintenance of the Missouri River Bank Stabilization and Navigation Project (BSNP), and Operation of the Kansas River Reservoir System" prepared by the U.S. Fish and Wildlife Service (Service) dated November 30,2000 and the Amendment, thereto, dated December 16,2003.

This annual report documents the Corps threatened and endangered species conservation activities to comply with the provisions of the 2000 BiOp and the 2003 Amendment to …

U.S. Army Corps Of Engineers Omaha District Monthly Drought Report, August 2005

United States Army Corps of Engineers, Omaha District

Missouri River Basin Drought Overview

Pre-Settlement Drought

Drought Since 1895

Current Conditions

Drought Outlook 1

Ft. Peck, Montana

Reservoir Elevation Overview

Water Intake Overview

Access Overview

Noxious Weeds Overview

Cultural Resources Overview

Garrison, North Dakota

Reservoir Elevation Overview

Water Intake Overview

Access Overview

Boat Ramp Information

Noxious Weeds Overview

Cultural Resources Overview

Other Areas of Interest/Concern

Oahe, South Dakota

Reservoir Elevation Overview

Water Intake Overview

Access Overview

Noxious Weeds Overview

Cultural Resources Overview

Mainstem Reservoir Information, Weekly Elevation Comparison 27 JUN 2005 through 1 AUG 2005

Mainstem Reservoir Storage Comparison Water Year 2004 vs. Water Year 2005

Ft. Peck, MT …

U.S. Army Corps Of Engineers Omaha District Monthly Drought Report, July 2005

United States Army Corps of Engineers, Omaha District

Drought Monitor Overview

Latest Seasonal Assessment

U.S. Seasonal Drought Outlook

U.S. Drought Monitor

National Drought Summary July 12, 2005

Current Drought Impacts in the United States

Drought Severity Index by Division

Mainstem Reservoir Information

Reservoir Control Center Predictions

Basic Simulation

Lower Basic Simulation

Upper Basic Simulation

Ft. Peck, Montana

Reservoir Elevation Overview

Water Intake Overview

Access Overview

Noxious Weeds Overview

Cultural Resources Overview

FY 05 Action Items

Garrison, North Dakota

Reservoir Elevation Overview

Water Intake Overview

Access Overview

Boat Ramp Information

Noxious Weeds Overview

Cultural Resources Overview

Other Areas of Interest/Concern

Oahe Assessment

Reservoir Elevation Overview

Water Intake Overview

Access …