Engineering Commons^™

Investigation Of The Shear Stiffness Of Profiled Steel Sheeting Diaphragms With Only Two Edges Fastened, M. Duerr, H. Saal

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

No abstract provided.

A Simplified Method Of Evaluating Lateral Strengths Of Shear Wall Panels With Cold Formed Steel Framing, Lei Xu

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

No abstract provided.

Testing And Design Of Light Gauge Steel Frame 9mm Osb Panel Shear Walls, C. Blais

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

No abstract provided.

Shear Lag Effect On Bolted L-Shaped Metal Studs In A Wall Assembly, Chi-Ling Pan

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

No abstract provided.

Single Bolted Tension Member Design - A New Approach, D. M. Fox, R. M. Schuster

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

No abstract provided.

Composite (La, Sr)Mno3-Ysz Cathode For Sofc, Toshio Suzuki, Masanobu Awano, Piotr Jasinski, Vladimir Petrovsky, Harlan U. Anderson

Materials Science and Engineering Faculty Research & Creative Works

(La, Sr) MnO₃ (LSM)-Y doped ZrO₂ (YSZ) composite was prepared using YSZ colloidal suspension (initial YSZ particle size ∼100 nm), YSZ and LSM polymer precursors on dense substrates at 800 °C annealing temperature. the results of a symmetrical LSM-YSZ composite cell test showed the area specific resistance for overpotential of 0.14 Ω cm2 at 800 °C, which indicated that the LSM-YSZ composite could be a potential candidate for cathode in SOFCs. the performance of the cell with the LSM-YSZ composite cathode and Ni-YSZ anode was investigated and the power density of about 0.26 W cm- 2 was obtained …

Effect Of Friction Stir Processing On The Microstructure Of Cast A356 Aluminum, Z. Y. Ma, S. R. Sharma, Rajiv S. Mishra

Materials Science and Engineering Faculty Research & Creative Works

Friction stir processing (FSP) was applied to cast A356 Al to modify the as-cast microstructure. FSP homogenizes and refines the cast microstructure, completely eliminates porosity, and creates a microstructure with fine Si particles (0.25-0.42 μm) distributed in a fine grain aluminum matrix (3-4 μm). Further, FSP parameters significantly influence microstructural development in the processed zone of cast A356 Al. Generally, higher tool rotation rate creates a more homogeneous microstructure. at lower tool rotation rates, a macroscopically visible banded structure characterized by a low density of coarse particles, was detected in the nugget zone. However, FSP parameters did not significantly influence …

Torque Ripple Sensor And Mitigation Mechanism, Jason Neely, Steven Pekarek, Jason M. Banaskavich, Daniel S. Stutts

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A torque ripple sensor and method for torque ripple sensing and/or mitigation. A piezoelectric sensor is positioned relative to a motor so that torque fluctuations due to torque ripple of the motor are transmitted to the sensor, resulting in strain of a piezoelectric element. A resulting signal can be amplified and conditioned for determining a magnitude of the torque ripple and/or fed into a feedback loop for applying current control or a counter-torque to the motor for torque ripple mitigation.

Lagrangian Mixing In Decaying Stably Stratified Turbulence, Subhas K. Venayagamoorthy, Derek D. Stretch

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Direct numerical simulations are used to study mixing and dispersion in decaying stably stratified turbulence from a Lagrangian perspective. The change in density of fluid particles owing to small-scale mixing is extracted from the simulations to provide insight into the mixing process. These changes are driven by temporally and spatially intermittent events that are strongly suppressed as the stratification increases and overturning motions disappear. This occurs for times Nt > 2π i.e. after one buoyancy period, where N is the buoyancy frequency. The role of small-scale mixing processes in the density (or buoyancy) flux is analyzed. After an initial transient, we …

Internal Small Volume Storage Water Heater, Kelly Homan

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The invention concerns devices for water storage, heating and delivery. A storage water heater of the invention provides an amount of unmixed recently heated water from an internal small volume during a draw along with water from a main volume. When water is drawn from the storage water heater, an amount of recently heated water substantially unmixed with the remaining volume of the tank is drawn along with heated water from the remaining volume. Substantial performance increases in the hot water that may be delivered over a period, such as an hour, may be achieved compared to an otherwise identical …

Investigation Of Cause Of Cracked Stringer On The Blanchette Bridge, Ward Marianos Jr., Genda Chen, Nestore Galati, Fabio Matta

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The Blanchette Bridge carries Interstate 70 across the Missouri River, connecting St. Louis and St. Charles counties in eastern Missouri. The westbound bridge was constructed in 1958. In 1979, the original reinforced concrete roadway deck on the bridge was replaced with a steel grid deck system, welded to supporting girders and stringers. In 1999 and 2005, cracks were discovered in stringers on the bridge approach spans. The stringers were repaired with bolted splices.

The investigation of the cracking included preliminary analyses, review of historical documents, detailed finite element analyses, and field testing of the bridge. The cracking was determined to …

Seismic Retrofit Of Ciss Pile Bent Cap Connections, Michael C. Lubiewski, Pedro Franco Silva, Genda Chen

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Three 4/5-scale units were cast, retrofitted, and tested under simulated seismic loads. These units were built to model a bridge bent consisting of a cast in place steel shell (CISS) column foundation shaft and a bent cap configured to form a tee connection. Each unit was retrofitted in the column, bent cap, and their connection according to current seismic design standards. The main objective was to ensuring ductile performance under lateral loads.

Specific seismic improvements made to the column and the bent cap system were: (1) the moment capacity of the column was reduced by cutting a portion of the …

Prediction Of Intrauterine Pressure From Electrohysterography Using Optimal Linear Filtering, Mark D. Skowronski, John G. Harris, Dorothee E. Marossero, Rodney K. Edwards, Tammy Yachabach Euliano

Electrical and Computer Engineering Faculty Research & Creative Works

We propose a method of predicting intrauterine pressure (IUP) from external electrohysterograms (EHG) using a causal FIR Wiener filter. IUP and 8-channel EHG data were collected simultaneously from 14 laboring patients at term, and prediction models were trained and tested using 10-min windows for each patient and channel. RMS prediction error varied between 5-14 mmHg across all patients. We performed a 4-way analysis of variance on the RMS error, which varied across patients, channels, time (test window) and model (train window). The patient-channel interaction was the most significant factor while channel alone was not significant, indicating that different channels produced …

Efficient And Robust Delay-Insensitive Qca (Quantum-Dot Cellular Automata) Design, Minsu Choi, Myungsu Choi, Zachary D. Patitz, Nohpill Park

Electrical and Computer Engineering Faculty Research & Creative Works

The concept of clocking for QCA, referred to as the four-phase clocking, is widely used. However, inherited characteristics of QCA, such as the way to hold state, the way to synchronize data flows, and the way to power QCA cells, make the design of QCA circuits quite different from VLSI and introduce a variety of new design challenges. The most severe challenges are due to the fact that the overall timing of a QCA circuit is mainly dependent upon its layout. This issue is commonly referred to as the "layout =timing" problem. To circumvent the problem, a novel self-timed circuit …

Millimeter-Wave Differential Probe For Nondestructive Detection Of Corrosion Precursor Pitting, Mohammad Tayeb Ahmad Ghasr, Brian D. Carroll, Sergey Kharkovsky, Russell A. Austin, R. Zoughi

Electrical and Computer Engineering Faculty Research & Creative Works

Critical aircraft structural components, such as wings and fuselages, are exposed to harsh environments that vary considerably in temperature and moisture content. In most cases, the corrosion is hidden under paint and primer and cannot be visually detected. The initiation of corrosion is preceded by the presence of corrosion precursor pitting. Near-field millimeter-wave nondestructive testing (NDT) methods have been successfully used for detecting corrosion precursor pitting in exposed as well as painted aluminum substrates. However, near-field millimeter-wave measurements are susceptible to clutter that may mask indications of small defects such as pitting. Standoff distance variation produces an unwanted intensity gradient …

Nonlinear Modified Pi Control Of Multi-Module Gcscs In A Large Power System, Swakshar Ray, Ganesh K. Venayagamoorthy

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents the design of a new control strategy for gate-controlled series compensators (GCSCs). GCSCs are new FACTS devices which can provide active power flow control on a transmission line. Proper placement of GCSCs in proximity to generators can also provide damping to system oscillations. This paper has investigated the effectiveness of multiple multi-module gate controlled series compensators (MMGCSCs) for large power systems. MMGCSCs can be less expensive devices with wide range of control of capacitive reactance in series with transmission lines. A nonlinear modified PI (NMPI) control is developed to provide power flow control and enhanced transient stability …

Bio-Inspired Algorithms For The Design Of Multiple Optimal Power System Stabilizers: Sppso And Bfa, Tridib Kumar Das, Ganesh K. Venayagamoorthy

Electrical and Computer Engineering Faculty Research & Creative Works

Power System Stabilizers (PSSs) provide stabilizing control signals to excitation systems to damp out inter-area and intra-area oscillations. The PSS must be optimally tuned to accommodate the variations in the system dynamics. Designing multiple optimal PSSs is a challenging task for researchers. This paper presents the comparison between two bio-inspired algorithms: a Small Population based Particle Swarm Optimization (SPPSO) and the Bacterial Foraging Algorithm (BFA) for the simultaneous tuning of a number of PSSs in a multi-machine power system. The cost function to be optimized by both algorithms takes into consideration the time domain transient responses. The effectiveness of the …

Adaptive Critic Neural Network Force Controller For Atomic Force Microscope-Based Nanomanipulation, Qinmin Yang, Jagannathan Sarangapani

Electrical and Computer Engineering Faculty Research & Creative Works

Automating the task of nanomanipulation is extremely important since it is tedious for humans. This paper proposes an atomic force microscope (AFM) based force controller to push nano particles on the substrates. A block phase correlation-based algorithm is embedded into the controller for the compensation of the thermal drift which is considered as the main external uncertainty during nanomanipulation. Then, the interactive forces and dynamics between the tip and the particle, particle and the substrate are modeled and analyzed. Further, an adaptive critic NN controller based on adaptive dynamic programming algorithm is designed and the task of pushing nano particles …

High Efficiency Energy Storage System Design For Hybrid Electric Vehicle With Motor Drive Integration, Shuai Lu, Keith Corzine, Mehdi Ferdowsi

Electrical and Computer Engineering Faculty Research & Creative Works

This paper proposes a new energy storage system (ESS) design including both batteries and ultracapacitors (UC) in hybrid electric vehicle (HEV) and electric vehicle (EV) applications. The conventional designs require a dc-dc converter to interface the UC unit. Herein, the UC can be directly switched across the motor drive dc-link during the peak power demands. The resulting wide voltage variation due to UC power transfer is addressed by the simple modulator introduced in this paper, so that the motor drive performance is not disrupted. Based on this new methodology, the paper further introduces two ESS schemes with different topologies, UC …

Inherited Redundancy And Configurability Utilization For Repairing Nanowire Crossbars With Clustered Defects, Yadunandana Yellambalase, Minsu Choi, Yong-Bin Kim

Electrical and Computer Engineering Faculty Research & Creative Works

With the recent development of nanoscale materials and assembly techniques, it is envisioned to build high-density reconfigurable systems which have never been achieved by the photolithography. Various reconfigurable architectures have been proposed based on nanowire crossbar structure as the primitive building block. Unfortunately, high-density systems consisting of nanometer-scale elements are likely to have many imperfections and variations; thus, defect-tolerance is considered as one of the most exigent challenges. In this paper, we evaluate three different logic mapping algorithms with defect avoidance to circumvent clustered defective crosspoints in nanowire reconfigurable crossbar architectures. The effectiveness of inherited redundancy and configurability utilization is …

Large Scale Signal And Interconnect Fdtd Modeling For Bga Package, Xiaohe Chen, James L. Drewniak, Jianmin Zhang, Michael A. Cracraft, Bruce Archambeault, Samuel R. Connor

Electrical and Computer Engineering Faculty Research & Creative Works

This paper introduces a Finite-Difference Time-Domain (FDTD) approach to modeling portions of Ball Grid Array (BGA) package interconnect circuits. A fullwave circuit model including vias, trace segments, and ground vias was generated, using a computer gridding tool, and fed into the FDTD (Taflove and Hagness, 2005) program. The simulated results were correlated with TDR measurements.

Intelligent Integration Of A Wind Farm To An Utility Power Network With Improved Voltage Stability, V. K. Polisetty, Sandhya R. Jetti, Ganesh K. Venayagamoorthy, Ronald G. Harley

Electrical and Computer Engineering Faculty Research & Creative Works

The increasing effect of wind energy generation will influence the dynamic behavior of power systems by interacting with conventional generation and loads. Due to the inherent characteristics of wind turbines, non-uniform power production causes variations in system voltage and frequency. Therefore, a wind farm requires high reactive power compensation. Flexible AC transmission systems (FACTS) devices such as SVCs inject reactive power into the system which helps in maintaining a better voltage profile. This paper presents the design of a linear and a nonlinear coordinating controller between a SVC and the wind farm inverter at the point of interconnection. The performances …

Ac Impedance Measurement By Line-To-Line Injected Current, Keith Corzine, Jing Huang

Electrical and Computer Engineering Faculty Research & Creative Works

Naval ship as well as aerospace power systems are incorporating a greater degree of power electronic switching sources and loads. Although these components provide exceptional performance, they are prone to instability due to their high efficiency and constant power characteristics which lead to a negative impedance nature. When designing these systems, system integrators must consider the impedance versus frequency at an interface (which designates source and load). Stability criteria have been developed in terms of source and load impedance for both DC and AC systems and it is often helpful to have techniques for impedance measurement. For DC systems, the …

An Unique Ultracapacitor Direct Integration Scheme In Multilevel Motor Drives For Large Vehicle Propulsion, Shuai Lu, Keith Corzine, Mehdi Ferdowsi

Electrical and Computer Engineering Faculty Research & Creative Works

This paper introduces a new set of methods to directly integrate ultracapacitor banks into cascaded multilevel inverters used for large vehicle propulsion. The idea is to replace the regular dc-link capacitors with ultracapacitors in order to combine the energy storage unit and motor drive. This approach eliminates the need for an interfacing dc-dc converter and considerably improves the efficiency of regenerative braking energy restoration in electric and hybrid vehicles. Utilizing the proposed modulation control set, the two cascaded inverters can have their dc voltage levels maintained at any ratio (even a noninteger ratio) or dynamically varied over a wide range …

Real-Time Implementation Of A Dual Function Neuron Based Wide Area Svc Damping Controller, Sandhya R. Jetti, Ganesh K. Venayagamoorthy

Electrical and Computer Engineering Faculty Research & Creative Works

The use of wide area measurements for power system stabilization is recently given a lot of attention by researchers and the power industry to avoid cascading failures and blackouts such as the August 2003. This paper presents the design of a nonlinear external damping controller based on wide area measurements as inputs to a dual function neuron (DFN). This DFN controller is specifically designed to enhance the damping characteristics of a power system considering the nonlinearity in the system. The major advantage of the DFN controller is that it is simple in structure with less development time and hardware requirements …

Development Of Cost-Effective, Energy Efficient Steel Framing: Structural Performance Of Slit-Web Steel Wall Studs, Roger A. Laboube

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

No abstract provided.

Development Of Cost-Effective, Energy Efficient Steel Framing: Thermal Performance Of Slit-Web Steel Wall Studs, Roger A. Laboube

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

No abstract provided.

Corrosion Of Galvanized Fasteners Used In Cold-Formed Steel Framing, Roger A. Laboube

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

The primary objective of this project was to study the effect of corrosion on the structural integrity of galvanized fasteners used in cold-formed steel-framed construction. A number of specific tasks were developed to meet this objective, including a literature search, design and construction of field enclosures, determination of test sites and installation of field enclosures, test specimen design and fabrication, accelerated corrosion testing, structural tensile testing, data analysis and technology transfer.

Enhancement Of Crystal Growth And Superconducting Properties Of Melt-Textured Yba2cu3o7−X Through Addition Of Baceo3 And Basno3, Oratai Jongprateep, Fatih Dogan

Materials Science and Engineering Faculty Research & Creative Works

The effects of additions of BaSnO₃ in combination with BaCeO₃ on the microstructure, crystal growth and superconducting properties of melt-textured YBa₂Cu₃O_7−x (Y123) have been investigated. It has been reported that the addition of BaCeO₃ to Y123 results in an increase in the critical current density. However, higher cerium concentrations affect the solidification process and inhibit the growth of melt-textured Y123 single crystals. BaSnO₃ has been shown to restore the properties of Y123 with BaCeO₃ additives. Increasing the amount of added BaSnO₃ leads to refinement of Y211 particles, enhancement of …

Magnetic Nanoparticle Supported Catalyst For Atom Transfer Radical Polymerization, Shijie Ding, Yangchuan Xing, Maciej Radosz, Youqing Shen

Chemical and Biochemical Engineering Faculty Research & Creative Works

Magnetic nanoparticles were used to support an ATRP catalyst for the polymerization of methyl methacrylate (MMA) for minimized adverse effect of catalyst support and easy catalyst separation. the nanoparticle-supported catalyst mediated a living/controlled radical polymerization of MMA as effectively as unsupported catalysts. with the addition of 22 mol % of CuBr 2, the polymer molecular weights were well-controlled with an initiator efficiency of 0.85 and polydispersity lower than 1.2. the supported catalysts could be easily separated/isolated using an external magnetic field and reused with slightly decreased activity but further improved control. the activity of the recycled catalyst was regenerated by …