Engineering Commons^™

Stormwater Irrigation Volume Iii: Transport Of The Cyanotoxin Microcystin In Groundwater Beneath Stormwater Ponds: Results Of Soil Column Experiments, Martin Wanielista

BMP Trains Research and Publications

As the demand for fresh water increases in central Florida to meet both public supply and irrigation needs, stormwater is increasingly being managed as a resource to help offset possible future declines in aquifer water levels. Water quality is an important consideration when using stormwater for recharge or harvesting. A constituent of recent concern is cyanobacteria (popularly known as blue-green algae) because some of these can produce toxins (cyanotoxins) that are detrimental to animal and human health. Microcystins are the most commonly found type of cyanotoxin in Florida and have been detected in a variety of rivers, natural lakes, and …

Recipient Of The 2009 Alumni Titan Award, Joshua A. Gerlick '99

Alumni Titan Award

Joshua A. Gerlick has provided outstanding service to IMSA and is a loyal and generous supporter of the IMSA Fund. In early 2005, Gerlick participated in phone interviews for the IMSA TALENT Director. He also returned to the Academy in 2005 to serve as the Convocation speaker, and again in 2006 as an Intersession facilitator. During the 2006-07 school year, Gerlick dedicated a substantial amount of time towards volunteering at IMSA, in addition to relocating his home and business from Pittsburgh to Michigan. He served as a class agent for the annual fund, personally soliciting former classmates on behalf of …

Squeeze-Film Damping Of Flexible Microcantilevers At Low Ambient Pressures: Theory And Experiment, Jin Woo Lee, Ryan Tung, Arvind Raman, Hartono Sumali, John Sullivan

PRISM: NNSA Center for Prediction of Reliability, Integrity and Survivability of Microsystems

An improved theoretical approach is proposed to predict the dynamic behavior of long, slender and flexible microcantilevers affected by squeeze-film damping at low ambient pressures. Our approach extends recent continuum gas damping models which were originally derived for a rigid oscillating plate near a wall, to flexible microcantilevers for calculating and predicting squeeze-film damping ratios of higher order bending modes at reduced ambient pressures. Theoretical frequency response functions are derived for a flexible microcantilever beam excited both inertially and via external forcing. Experiments performed carefully at controlled gas pressures are used to validate our theoretical approach over five orders of …

Shear Rate Threshold For The Boundary Slip In Dense Polymer Films, Nikolai V. Priezjev

Mechanical and Materials Engineering Faculty Publications

The shear rate dependence of the slip length in thin polymer films confined between atomically flat surfaces is investigated by molecular dynamics simulations. The polymer melt is described by the bead-spring model of linear flexible chains. We found that at low shear rates the velocity profiles acquire a pronounced curvature near the wall and the absolute value of the negative slip length is approximately equal to thickness of the viscous interfacial layer. At higher shear rates, the velocity profiles become linear and the slip length increases rapidly as a function of shear rate. The gradual transition from no-slip to steady-state …

Optimal Placement And Signal Selection For Wide-Area Controlled Upfcs For Damping Power System Oscillations, Mahyar Zarghami, Mariesa Crow

Electrical and Computer Engineering Faculty Research & Creative Works

The paper discusses an optimal placement for UPFCs and an optimal method for the selection of global measurements in a wide-area controlled network for the purpose of damping power system oscillations. Both the placement and signal selection methods are optimized to damp interarea oscillations. Optimal UPFC placement is identified by comparing different candidate placements based on the total damping they produce. Optimal selection of output measurements is based on the projection of the right eigenvectors on outputs. after the selection of the desired output measurements, observer gains are designed by LMI approaches. Test results from the IEEE 57 bus test …

Getting An Nsf Career Award And Beyond, Ganesh Kumar Venayagamoorthy

Electrical and Computer Engineering Faculty Research & Creative Works

The National Science Foundation (NSF), USA, CAREER program is a premier program that emphasizes the importance the Foundation places on the early development of academic careers solely dedicated to stimulating the discovery process in which the excitement of research enriched by inspired teaching and enthusiastic learning. This paper presents the research and education experiences gained by the principal investigator - Vinayagamoorthy and his research collaborators and students as a result of a NSF CAREER proposal been awarded by the Power, Control and Adaptive Networks (PCAN) program of the Electrical, Communications and Cyber Systems Division, effective June 1, 2004. the main …

Improving The Dynamic Performance Of Wind Farms With Statcom, Aditya P. Jayam, Badrul H. Chowdhury

Electrical and Computer Engineering Faculty Research & Creative Works

When integrated to the power system, large wind farms can pose voltage control issues among other problems. a thorough study is needed to identify the potential problems and to develop measures to mitigate them. Although integration of high levels of wind power into an existing transmission system does not require a major redesign, it necessitates additional control and compensating equipment to enable (fast) recovery from severe system disturbances. the use of a Static Synchronous Compensator (STATCOM) near a wind farm is investigated for the purpose of stabilizing the grid voltage after grid-side disturbance such as a three-phase short circuit fault. …

The Extraction Of Cytochrome C And Dsred2 Into Reverse Micelles, Michelle Baker

Theses and Dissertations

Cytochrome c and DsRed2 were successfully extracted into reverse micelles by the contacting of an aqueous protein-containing phase with an organic phase. Two important properties that differentiate the extraction profiles of these proteins are pI and size. Cytochrome c is a relatively small, monomeric protein with a pI of 10.6. It was easily extracted into reverse micelles with the anionic surfactant AOT. DsRed2, however, is a large tetramer with a p1 of 6.3. It could not be extracted into AOT, but was extracted with the cationic surfactant CTAB, and with a wider error range than cytochrome c. CD data indicate …

East Bay Energy Consortium Meeting Minutes, September 21, 2009, East Bay Energy Consortium

East Bay Energy Consortium Meeting Minutes

No abstract provided.

Multidisciplinary Design Optimization Of An Extreme Aspect Ration Hale Uav, Bryan Morrisey, Robert A. Mcdonald

Aerospace Engineering

Development of High Altitude Long Endurance (HALE) aircraft systems is part of a vision for a low cost communications/surveillance capability. Applications of a multi payload aircraft operating for extended periods at stratospheric altitudes span military and civil genres and support battlefield operations, communications, atmospheric or agricultural monitoring, surveillance, and other disciplines that may currently require satellite-based infrastructure. The central goal of this research was the development of a multidisciplinary tool for analysis, design, and optimization of HALE UAVs, facilitating the study of a novel configuration concept. Applying design ideas stemming from a unique WWII-era project, a "pinned wing" HALE aircraft …

Cost-Benefit Analysis Of Error Reduction For Complex Systems, Robert A. Mcdonald

Aerospace Engineering

The cost-benefit tradeoff of analysis fidelity in complex systems analysis has been posed as an optimization problem providing quantitative guidance for investment in improving analysis. A nonlinear constrained optimizer to solve this problem has been integrated into an error tradeoff environment providing an intuitive tool for the decision maker to consider investment in fidelity at the same time as design decisions are considered. An example demonstrates the efficacy of the improved interface to enable fidelity improvement investment decisions.

A Variable Step-Size Lmp Algorithm For Heavy-Tailed Interference Suppression In Phased Array Radar, Yahong Rosa Zheng, Tiange Shao

Electrical and Computer Engineering Faculty Research & Creative Works

A new variable step-size Least Mean p-norm (VSS-LMP) algorithm is proposed for phased array radar application with space-time adaptive processing to combat heavy-tailed non-Gaussian clutters. the algorithms automatically change the step size according to the estimated p-th and (2p - 2)-th moments of the error, where 1 ≤ p ≤ 2. the algorithm is evaluated via a space-slow-time STAP example and the excess Mean Square Error (MSE) and mis adjustment results show that the proposed vs.S-LMP converges fast and reaches lower steady-state error than the fixed step size LMP. It also provides a better compromise between convergence speed and low …

Performances Of Variable Step-Size Adaptive Algorithms In Non-Gaussian Interference Environments, Yahong Rosa Zheng, Robert Lynch

Electrical and Computer Engineering Faculty Research & Creative Works

Two variable step-size normalized least mean square (VSS-NLMS) algorithms, namely the non-parametric vs.S-NLMS and Switched Mode vs.S-NLMS, are reformulated into complex signal form for STAP applications. the performances of these two vs.S NLMS algorithms in Gaussian and compound-K clutters are evaluated via a phased array space-slow-time STAP example. We find that the mis adjustment behaviors are inconsistent with the excess MSEs which is a better measure of STAP performance. Both vs.S-NLMS algorithms outperform conventional fixed step size (FSS) NLMS algorithms with fast convergence and low steady-state excess MSE. the SM-VSS-NLMS provides a better performance compromise than the NP-VSS-NLMS with much …

Cracked Rotor Detection By Recurrence Plots, Grzegorz Litak, Jerzy T. Sawicki, Rafał Kaspereka

Mechanical Engineering Faculty Publications

Recurrence plots (RPs) analysis has been used to distinguish cracked and healthy rotor responses. It has been shown that the recurrence criteria of the dynamical systems defined by the RPs can indicate the damages of the rotating shaft using relatively short time series.

Work In Progress - A Mixed-Methods Approach To Developing An Instrument Measuring Engineering Students' Positive Ethical Behavior, Mathew A. Holsapple, Cynthia J. Finelli, Donald D. Carpenter, Trevor S. Harding, Janel A. Sutkus

Materials Engineering

Ethics education and the drive to produce ethical professional engineers is an important focus of one body of research on engineering education. This research often defines the positive outcome of ethics education as students and professional engineers choosing not to engage in unethical behavior. This paper discusses a portion of a larger research project and details efforts to identify and validate a definition of ethical behavior that includes the decision to engage in a positive behavior, defined as a service to a larger community. Through a series of interviews and focus groups with engineering administrators, faculty, and students, the authors …

Haptic Collision Avoidance For A Remotely Operated Quadrotor Uav In Indoor Environments, Adam M. Brandt

Theses and Dissertations

A quadrotor is an omnidirectional unmanned air vehicle that is suitable for indoor flight because of its ability to hover and maneuver in confined spaces. The remote operation of this type of vehicle is difficult due to a lack of sensory perception; typically, the view from the onboard camera is the only information transmitted to the pilot. This thesis proposes using force feedback exerted by the command input device on the hand of the pilot to assist in avoiding collisions while navigating in indoor environments. Five candidate algorithms are presented for calculating the forces to be felt by the pilot …

Motion Analysis Of Fluid Flow In A Spinning Disk Reactor, Valentina N. Korzhova

USF Tampa Graduate Theses and Dissertations

The flow of a liquid film over a rapidly rotating horizontal disk has numerous industrial applications including pharmaceuticals, chemical engineering, bioengineering, etc. The analysis and control of complex fluid flows over a rapidly rotating horizontal disk is an important issue in the experimental fluid mechanics. The spinning disk reactor exploits the benefits of centrifugal force, which produces thin highly sheared films due to radial acceleration. The hydrodynamics of the film results in excellent fluid mixing and high heat or mass transfer rates.

This work focuses on developing a novel approach for fluid flow tracking and analysis. Specifically, the developed algorithm …

Phage-Induced Alignment Of Membrane Proteins Enables The Measurement And Structural Analysis Of Residual Dipolar Couplings With Dipolar Waves And Lambda-Maps, Sang Ho Park, Woo Sung Son, Rishi Mukhopadhyay, Homayoun Valafar, Stanley J. Opella

Faculty Publications

At pH > 6 added filamentous bacteriophage fd is compatible with many of the detergents used to solubilize membrane proteins for solution NMR studies of membrane proteins and, therefore, serves as an alignment media. In combination with strained polyacrylamide gel alignment, Dipolar Waves can be used to directly assess the secondary structure and a λ-map extracts the order tensors for de novo structure calculation of membrane proteins without distance restraints.

Compact Optical Curvature Sensor With A Flexible Microdisk Laser On A Polymer Substrate, Wan Kuang, M. H. Shih, K. S. Hsu, Y. C. Yang, Y. C. Wang, S. K. Tsai, Y. C. Liu, Z. C. Chang, M. C. Wu

Electrical and Computer Engineering Faculty Publications and Presentations

In this paper, a chip-scale compact optical curvature sensor was demonstrated. It consists of a low threshold InGaAsP microdisk laser on a flexible polydimethylsiloxane polymer substrate. The curvature dependence of lasing wavelength was characterized by bending the cavity at different bending radii. The measurements showed that the lasing wavelength decreases monotonously with an increasing bending curvature. A good agreement between experiment and three-dimensional finite-difference time-domain simulation was also obtained. The sensitivity of the compact device to the bending curvature is -23.7 nm/mm form the experiment.

Indirect Compensation Techniques For Three-Stage Cmos Op-Amps, Vishal Saxena, R. Jacob Baker

Electrical and Computer Engineering Faculty Publications and Presentations

As CMOS technology continues to evolve, the supply voltages are decreasing while at the same time the transistor threshold voltages are remaining relatively constant. Making matters worse, the inherent gain available from the nano-CMOS transistors is dropping. Traditional techniques for achieving high-gain by vertically stacking (i.e. cascoding) transistors becomes less useful in nano-scale CMOS processes. Horizontal cascading (multi-stage) must be used in order to realize high-gain op-amps in low supply voltage processes. This paper discusses new design techniques for the realization of three-stage op-amps. The proposed and experimentally verified op-amps, fabricated in 500 nm CMOS, typically exhibit 30 MHz unity-gain …

A K-Delta-1-Sigma Modulator For Wideband Analog To Digital Conversion, Vishal Saxena, Kaijun Li, Geng Zheng, R. Jacob Baker

Electrical and Computer Engineering Faculty Publications and Presentations

As CMOS technology shrinks, the transistor speed K-quantizing paths and can achieve significantly higher conversion bandwidths when compared to the traditional deltasigma ADCs. The 8-path KD1S modulator achieves an SNR of 58 dB (or 9.4-bits resolution) when clocked at 100 MHz for a conversion bandwidth of 6.25 MHz and an effective sampling rate equal to 800 MHz. The KD1S modulator has been fabricated in a 500 nm CMOS process and the experimental results are reported. Deficiencies in the first test chip performance are discussed along with their alleviation to achieve theoretical performance.

A Modified Newton Method For Solving Non-Linear Algebraic Equations, Satya N. Atluri, Chein-Shan Liu, Chung-Lun Kuo

Journal of Marine Science and Technology–Taiwan

The Newton algorithm based on the “continuation” method may be written as being governed by the equation xj(t) + Bij-1 Fi(xj) = 0, where Fi(xj) = 0, i, j = 1, …n are nonlinear algebraic equations (NAEs) to be solved, and Bij = ∂Fi /∂xj is the corresponding Jacobian matrix. It is known that the Newton's algorithm is quadratically convergent; however, it has some drawbacks, such as being sensitive to the initial guess of solution, and being expensive in the computation of the inverse of Bij at each iterative step. How to preserve the convergence speed, and to remove the …

Simulation Of Cnt Composites Using Fast Multipole Bem, Zhen-Han Yao, Jun-Dong Xu, Hai-Tao Wang, Xiao-Ping Zheng

Journal of Marine Science and Technology–Taiwan

This paper addresses some applications of the fast multipole boundary element method on the simulation of CNT composites, including the simulation of elastic, thermal and electric properties. The carbon nanotubes are treated as effective elastic fibers for the simulation of elastic property, and treated as straight fibers with high thermal conductivity and high electric conductivity for the simulation of thermal and electric properties respectively. The numerical examples are compared with other numerical results and experimental data published in literature. To reduce the difference between numerical and experimental value of effective elastic modulus, two approaches with nonideal interfacial condition or additional …

Novel Methods For Solving Severely Ill-Posed Linear Equations System, Chein-Shan Liu, Chih-Wen Chang

Journal of Marine Science and Technology–Taiwan

We treat an ill-posed system of linear equations by transforming it into a linear system of stiff ordinary differential equations (SODEs), adding a differential term on the left-hand side. In order to overcome the difficulty of numerical instability when integrating the SODEs, Liu [20] has combined nonstandard finite difference method and group-preserving scheme, namely the nonstandard group-preserving scheme (NGPS), to obtain an unconditional stable numerical method for SODEs. This paper applies the NGPS to the SODEs resulting from the ill-posed linear equations, and proves that the new algorithms are unconditional stable. To strengthen accuracy, an L-curve is used to select …

A Complete Stability Theory For The Kirchhoff Thin Plate Under All Kinds Of Actions, Shyh-Rong Kuo, Chih-Chang Chi, Yeong-Bin Yang

Journal of Marine Science and Technology–Taiwan

A complete stability theory for a plate can be constructed by an incremental virtual work equation describing instability effects induced by all kinds of actions. Besides, this incremental virtual work equation should satisfy the rigid body rule, i.e., it should objectively obey the rigid body rule no matter what coordinates systems are adopted. In this paper, a complete nonlinear stability theory for the Kirchhoff thin plate is proposed by using the principle of virtual work and the update Lagrangian formulation. Then, a rigid body motion testing method is developed for examining the incremental virtual work equation. In developing such a …

Computer Assisted Proof Of Spurious Eigensolution For Annular And Eccentric Membranes, I-Lin Chen, Jeng-Tzong Chen, Wei-Ming Lee, Shang-Kai Kao

Journal of Marine Science and Technology–Taiwan

Spurious eigensolutions in the boundary integral equation (BIE) or boundary element method (BEM) for doublyconnected domain problems, the eccentric and annular membranes, are studied analytically and numerically in this paper. For the mathematical analysis, we employ the null-field integral equation, the degenerate kernels and the Fourier series to prove the existence of spurious eigensolutions in the continuous system. Examples of eccentric case, annular membrane and general shape are solved by using the null-field equation approach and BEM, respectively. Based on the numerical experiment, computer-assisted proof for the existence of spurious eigenvalues in companion with the trivial outer boundary data is …

A Mathematical Revision Of The Landau-Lifshitz Equation, Chein-Shan Liu, Kuo-Ching Chen, Chau-Shioung Yeh

Journal of Marine Science and Technology–Taiwan

For the Landau-Lifshitz equation a Lie type linear system representation in the Minkowski space M3 1+ has been derived previously [25]. The internal symmetry group is a proper orthochronous Lorentz group SOo(3, 1), and the numerical method based on the internal symmetry was developed in [29]. This paper derives another four new representations of the Landau-Lifshitz equation. We prove that this equation admits two generators: one conservative and one dissipative, as well as two brackets: Poisson bracket and dissipative bracket. Upon embedding the Landau-Lifshitz equation into a skew-symmetric matrix space, we can develop a double-bracket flow representation. The conserved magnetization …

Method Of Fundamental Solutions With External Source For The Eigenfrequencies Of Waveguides, Chia-Ming Fan, Der-Liang Young, Chia-Lin Chiu

Journal of Marine Science and Technology–Taiwan

This study adopts a meshless numerical method, the combination of the method of fundamental solutions (MFS) and method of particular solutions (MPS) following the lead of Reutskiy, to determine the eigenfrequencies of four different waveguides, based on the principle of physical response of a system exposed to external source. The response amplitudes to determine the resonant frequencies for the eigenproblems are used. We use the MFS with external source (MFS-ES) and MPS to solve a sequence of inhomogeneous problems for the determination of the eigenfrequencies. This is an alternative to the typical methods of directly solving the homogeneous matrix system …

Perovskite-Type Oxide Thin Film Integrated Fiber Optic Sensor For High-Temperature Hydrogen Measurement, Xiling Tang, Kurtis Remmel, Xinwei Lan, Jiangdong Deng, Hai Xiao, Junhang Dong

Electrical and Computer Engineering Faculty Research & Creative Works

Small size fiber optic devices integrated with chemically sensitive photonic materials are emerging as a new class of high-performance optical chemical sensor that have the potential to meet many analytical challenges in future clean energy systems and environmental management. Here, we report the integration of a proton conducting perovskite oxide thin film with a long-period fiber grating (LPFG) device for high-temperature in situ measurement of bulk hydrogen in fossil- and biomass-derived syngas. the perovskite-type Sr(Ce 0.8Zr0.1)Y0.1O2.95 (SCZY) nanocrystalline thin film is coated on the 125 μm diameter LPFG by a facile polymeric precursor route. This fiber optic sensor (FOS) operates …

Boundary Particle Method For Inverse Cauchy Problems Of Inhomogeneous Helmholtz Equations, Wen Chen, Zhuojia Fu

Journal of Marine Science and Technology–Taiwan

This paper investigates the boundary particle method (BPM) coupled with truncated singular value decomposition (TSVD) regularization technique on the solution of inverse Cauchy problems of inhomogeneous Helmholtz equations. Unlike the other boundary discretization methods, the BPM does not require any inner nodes to evaluate the particular solution, since the method uses the recursive composite multiple reciprocity technique to reduce an inhomogeneous problem to a series of higher-order homogeneous problems. The BPM is particular attractive to solve inverse problems thanks to its truly boundary-only meshless merit. In this study, numerical experiments demonstrate that the BPM in conjunction with the TSVD is …