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Point Of Common Coupling (Pcc) Voltage Control Of A Grid-Connected Solar Photovoltaic (Pv) System, Brian K. Perera, Philip Ciufo, Sarath Perera Jan 2013

Point Of Common Coupling (Pcc) Voltage Control Of A Grid-Connected Solar Photovoltaic (Pv) System, Brian K. Perera, Philip Ciufo, Sarath Perera

Faculty of Engineering and Information Sciences - Papers: Part A

In future low voltage grids, with multiple inverter interfaced sources connected, voltage regulation may become a necessary task. The potential exists for inverter interfaced sources to be deployed to regulate the voltage at the point of common coupling (PCC) of each inverter interfaced sources. The PCC voltage regulation is attainable with inverter interfaced sources by dynamically controlling the amount of reactive power injected to the power distribution grid by individual systems. In the current research, a closed-loop controller is proposed to regulate the PCC voltage of a solar photovoltaic (PV) system that is connected to a single-phase power distribution feeder …


Graphene Micro-Substrate Induced High Electron-Phonon Coupling In Mgb2, W X. Li, X Xu, K S. B De Silva, F X. Xiang, S X. Dou Jan 2013

Graphene Micro-Substrate Induced High Electron-Phonon Coupling In Mgb2, W X. Li, X Xu, K S. B De Silva, F X. Xiang, S X. Dou

Faculty of Engineering and Information Sciences - Papers: Part A

Electron-phonon coupling strength was studied in graphene-MgB2 composites to explore the possibilities for a higher superconducting transition temperature (Tc). For the first time in the experimental work on MgB2, the Raman active E2g mode was split into two parts: a softened mode corresponding to tensile strain and a hardened mode attributed to the carbon substitution effect. The tensile strain effect is suggested to improve Tc of graphene-MgB2 composites because it increases the electron-phonon coupling strength of MgB2.


Multi-Physics Modeling Of Geomechanical Systems With Coupled Hydromechanical Behaviors, Ahmad Mohamed Jan 2013

Multi-Physics Modeling Of Geomechanical Systems With Coupled Hydromechanical Behaviors, Ahmad Mohamed

Electronic Theses and Dissertations

Geotechnical structures under realistic field conditions are usually influenced with complex interactions of coupled hydromechanical behavior of porous materials. In many geotechnical applications, however, these important coupled interactions are ignored in their constitutive models. Under coupled hydromechanical behavior, stress in porous materials causes volumetric change in strain, which causes fluid diffusion; consequently, pore pressure dissipates through the pores that results in the consolidation of porous material. The objective of this research wasto demonstrate the advantages of using hydromechanical models to estimate deformation and pore water pressure of porous materials by comparing with mechanical-only models. Firstly, extensive literature survey was conducted …


Coupling Effects Of Feed Solution Ph And Ionic Strength On The Rejection Of Boron By Nf/Ro Membranes, Kha Tu, Long Nghiem, Allan Chivas Dec 2012

Coupling Effects Of Feed Solution Ph And Ionic Strength On The Rejection Of Boron By Nf/Ro Membranes, Kha Tu, Long Nghiem, Allan Chivas

Long D Nghiem

The coupling effects of solution pH and ionic strength on boron rejection by nanofiltration (NF) and reverse osmosis (RO) membranes were investigated. Two NF membranes (namely NF270 and NF90) and three RO membranes (namely BW30, SW30 and UTC80) were used to provide a full spectrum of NF/RO membranes. The rejection of boron by all five membranes was pH-dependent. The dependency of boron rejection on the feed solution pH became much more substantial as the nominal salt (sodium or calcium) rejection value of the membrane decreased. At pH 11, boron rejections by the NF90 and the NF270 membranes were only 10% …


Method Of Moments Analysis Of An Aperture In A Thick Ground Plane, Ahmet Burak Olcen Dec 2012

Method Of Moments Analysis Of An Aperture In A Thick Ground Plane, Ahmet Burak Olcen

Electrical Engineering and Computer Science - Dissertations

The problem of electromagnetic scattering from and transmission through an arbitrarily shaped aperture is considered. The aperture is in a thick infinite perfectly conducting ground plane. The conducting walls of the cavity inside the ground plane are of arbitrary shape. The apertures at both ends of the cavity are also of arbitrary shape. The structure is illuminated by an incident plane electromagnetic wave. The Green's function for this complicated problem is almost impossible to determine. Therefore the surface equivalence principle is used to reduce this complex problem into three simpler ones. Each such problem consists of equivalent surface currents radiating …


Temperature And Frequency Dependent Giant Magnetodielectric Coupling In Dymn0.33fe0.67o3, Fang Hong, Zhenxiang Cheng, Xiaolin Wang Jan 2012

Temperature And Frequency Dependent Giant Magnetodielectric Coupling In Dymn0.33fe0.67o3, Fang Hong, Zhenxiang Cheng, Xiaolin Wang

Australian Institute for Innovative Materials - Papers

Perovskite DyMn0.33Fe0.67O3 experiences a paramagnetism-antiferromagnetism transition at 450K and spin reorientation at 290 K. Magnetodielectric properties were studied around the spin reorientation transition. Both giant positive and giant negative magnetodielectric coupling (MDC) were observed near room temperature. The MDC shows strong temperature and frequency dependence, and the sign changes from positive to negative when magnetic state transits from a canted antiferromagnetic state to a collinear antiferromagnetic state. Possible mechanisms are proposed based on the Maxwell-Wagner model, phase transition, the magnetoresistance effect, and spin-phonon coupling.


Specular Andreev Reflection In The Interface Of A Two-Dimensional Semiconductor With Rashba Spin-Orbit Coupling And A D-Wave Superconductor, Bo Lv, C Zhang, Zhongshui Ma Jan 2012

Specular Andreev Reflection In The Interface Of A Two-Dimensional Semiconductor With Rashba Spin-Orbit Coupling And A D-Wave Superconductor, Bo Lv, C Zhang, Zhongshui Ma

Faculty of Engineering - Papers (Archive)

We reveal that the recently discovered specular Andreev reflection (SAR) [C. W. J. Beenakker, Phys. Rev. Lett. 97, 067007 (2006)] can occur in semiconductors where the spin-orbit coupling is finite. We demonstrate this finding in the hybrid of a two-dimensional electron gas with Rashba spin-orbit coupling and a superconductor. In the limit of low density or a strong spin-orbit coupling, specular Andreev reflection is finite. We also show that unit electron-hole conversion is possible in a specular Andreev reflection due to the different topological structures of the equal-energy surface between electrons and holes. The SAR in the semiconductor is determined …


Structural Dependent Ultrafast Electron-Phonon Coupling In Multiferroic Bifeo 3 Films, Zuanming Jin, Yue Xu, Zhengbing Zhang, Gaofang Li, Xian Lin, Guohong Ma, Zhenxiang Cheng, Xiaolin Wang Jan 2012

Structural Dependent Ultrafast Electron-Phonon Coupling In Multiferroic Bifeo 3 Films, Zuanming Jin, Yue Xu, Zhengbing Zhang, Gaofang Li, Xian Lin, Guohong Ma, Zhenxiang Cheng, Xiaolin Wang

Faculty of Engineering - Papers (Archive)

The electronic energy relaxation of polycrystalline BiFeO3 films is studied using ultrafast pump-probe spectroscopy. After photo-excitation with femtosecond laser pulses, the relaxation of hot electrons is identified to decay with two different characteristic times. The fast process is attributed to scattering of electrons with lattice-vibration modes, and the slow one is corresponding to the spin-lattice thermalization. The electron-phonon coupling is characterized by the second moment of the Eliashberg function, khx2i. Due to the structural strain and symmetry breaking, the electron-phonon interaction strength of tetragonal BiFeO3 films is larger than that of rhombohedral counterparts


Correlating Uncompensated Antiferromagnetic Moments And Exchange Coupling Interactions In Interface Ion-Beam Bombarded Co90fe 10/Cofe-Oxide Bilayers, Chin Shueh, Pei-Shi Chen, David Cortie, Frank Klose, Wen-Chen Chen, T H. Wu, Johan Van Lierop, Ko-Wei Lin Jan 2012

Correlating Uncompensated Antiferromagnetic Moments And Exchange Coupling Interactions In Interface Ion-Beam Bombarded Co90fe 10/Cofe-Oxide Bilayers, Chin Shueh, Pei-Shi Chen, David Cortie, Frank Klose, Wen-Chen Chen, T H. Wu, Johan Van Lierop, Ko-Wei Lin

Faculty of Engineering and Information Sciences - Papers: Part A

The coercivity and exchange bias field of ferro-/antiferromagnetic Co 90Fe10/CoFe-oxide bilayers were studied as function of the surface morphology of the bottom CoFe-oxide layer. The CoFe-oxide surface structure was varied systematically by low energy (0-70 V) Argon ion-beam bombardment before subsequent deposition of the Co90Fe10 layer. Transmission electron microscopy results showed that the bilayer consisted of hcp Co90Fe10 and rock-salt CoFe-oxide. At low temperatures, enhanced coercivities and exchange bias fields with increasing ion-beam bombardment energy were observed, which are attributed to defects and uncompensated moments created near the CoFe-oxide surface in increasing amounts with larger ion-beam bombardment energies. Magnetometry results …


Thermal, Microstructural And Mechanical Coupling Analysis Model For Flatness Change Prediction During Run-Out Table Cooling In Hot Strip Rolling, Xiao-Dong Wang, Fei Li, Zheng-Yi Jiang Jan 2012

Thermal, Microstructural And Mechanical Coupling Analysis Model For Flatness Change Prediction During Run-Out Table Cooling In Hot Strip Rolling, Xiao-Dong Wang, Fei Li, Zheng-Yi Jiang

Faculty of Engineering and Information Sciences - Papers: Part A

Non-uniformity of temperature distribution across strip width direction is the ultimate reason why the flatness defect occurs on the strip after cooling process although the strip is flat at the exit of finishing mill. One thermal, microstructural and mechanical coupling analysis model for predicting flatness change of steel strip during the run-out table cooling process was established using ABAQUS finite element software. K Esaka phase transformation kinetics model was employed to calculate the phase transformation, and coupled with temperature calculation using the user subroutine program HETVAL. Elasto-plasticity constitutive equations of steel material, in which conventional elastic and plastic strains, thermal …


Coupling Powdered Activated Carbon (Pac) Adsorption With Membrane Bioreactor (Mbr) Treatment For Enhanced Removal Of Trace Organics, Luong Nguyen, Faisal Ibney Hai, Long Nghiem, Jinguo Kang, William Price Jan 2012

Coupling Powdered Activated Carbon (Pac) Adsorption With Membrane Bioreactor (Mbr) Treatment For Enhanced Removal Of Trace Organics, Luong Nguyen, Faisal Ibney Hai, Long Nghiem, Jinguo Kang, William Price

Faculty of Engineering and Information Sciences - Papers: Part A

the occurrence of trace organics such as pesticides, pharmaceutically active compounds, natural and synthetic hormones as well as varous industrial compounds in the aquatic environment is of great concern due to their potential adverse effects on human health and those of other biota. Therefore, the removal of these compounds from wastewater is an important consideration to ensure safe drinking water and better protection of the environment. In the literature, several techniques have been explored for trace organics removal, namely, conventional activated sludge, membrane bioreactors (MBRs), and absorptioin. However it has been found that neither MBR nor activated carbon on its …


A New Method For Coupling 2d And 3d Deterministic And Stochastic Radiation Transport Calculations, Joel Aaron Kulesza Aug 2011

A New Method For Coupling 2d And 3d Deterministic And Stochastic Radiation Transport Calculations, Joel Aaron Kulesza

Masters Theses

The objective of this body of work was to produce a code system capable of processing boundary angular flux data from discrete ordinates calculations in 2D and 3D Cartesian and cylindrical geometries into cumulative probability density functions that can be used with a Monte Carlo radiation transport code to define neutron and photon initial positions, directions, and energies. In order to accomplish this goal, the DISCO (DetermInistic-Stochastic Coupling Operation) code was created to interface between the DORT and TORT deterministic radiation transport codes and the MCNP stochastic radiation transport code. DISCO introduces new methods to use the boundary angular flux …


A Wind Tunnel Technique For The Identification Of Ship Airwake/Rotor Downwash Coupling, Stargel R. Doane Jul 2011

A Wind Tunnel Technique For The Identification Of Ship Airwake/Rotor Downwash Coupling, Stargel R. Doane

Mechanical & Aerospace Engineering Theses & Dissertations

A wind tunnel study is performed to analyze the interaction between ship airwakes and helicopter rotor downwash. This interaction is of interest to naval aviators and researchers as this phenomenon is thought to limit helicopter flight envelopes and increase the overall difficulty of maritime rotorcraft operations. In this study, a 1/50th scale simplified naval frigate model and appropriately scaled rotor model are used for all experimental work. A rotor thrust survey was conducted in the immediate vicinity of the landing deck. Two dimensional and stereo particle image velocimetry surveys and rotor thrust measurements with various rotor and ship configurations were …


Effects Of Coupling In Understanding The Surface Energy Balance In The Snake River Basin, Idaho, Thilinl Jaksa, Kevin Nuss, Venkataramana Sridhar May 2011

Effects Of Coupling In Understanding The Surface Energy Balance In The Snake River Basin, Idaho, Thilinl Jaksa, Kevin Nuss, Venkataramana Sridhar

Civil Engineering Faculty Publications and Presentations

An accurate estimation of surface fluxes and evapotranspiration is critical in understanding the hydrological and meteorological processes linking the land and the atmosphere. Due to difficulties in obtaining extensive and timely field measurements, land surface and atmospheric models are widely employed in estimating such fluxes. This study focuses on testing the ability of Noah LSM to simulate the surface fluxes both in an uncoupled mode and coupled within an atmospheric model. An agricultural area in the Snake River Basin in Idaho and its surrounding natural vegetation regions are the study area. Two model improvements are tested in this investigation: modification …


Two-Color Terahertz Response In Bilayer Graphene Nanoribbons With Spin-Orbit Coupling, Junfeng Liu, Bo Wang, Zhongshui Ma, Chao Zhang Jan 2011

Two-Color Terahertz Response In Bilayer Graphene Nanoribbons With Spin-Orbit Coupling, Junfeng Liu, Bo Wang, Zhongshui Ma, Chao Zhang

Faculty of Engineering - Papers (Archive)

We demonstrate that spin-orbit coupling can give rise to a strong terahertz response in metallic armchair bilayer graphene nanoribbons. The combination of the interlayer coupling and the spin-orbit coupling leads to double resonant optical response in the low frequency regime. The frequency separation of the two excitations is tunable with a gate voltage.


Coupling Effects Of Feed Solution Ph And Ionic Strength On The Rejection Of Boron By Nf/Ro Membranes, Kha Tu, Long Nghiem, Allan Chivas Jan 2011

Coupling Effects Of Feed Solution Ph And Ionic Strength On The Rejection Of Boron By Nf/Ro Membranes, Kha Tu, Long Nghiem, Allan Chivas

Faculty of Engineering - Papers (Archive)

The coupling effects of solution pH and ionic strength on boron rejection by nanofiltration (NF) and reverse osmosis (RO) membranes were investigated. Two NF membranes (namely NF270 and NF90) and three RO membranes (namely BW30, SW30 and UTC80) were used to provide a full spectrum of NF/RO membranes. The rejection of boron by all five membranes was pH-dependent. The dependency of boron rejection on the feed solution pH became much more substantial as the nominal salt (sodium or calcium) rejection value of the membrane decreased. At pH 11, boron rejections by the NF90 and the NF270 membranes were only 10% …


Oxidative Acetylenic Coupling Reactions As A Surface Chemistry Tool, Simone Ciampi, Michael James, Nadim A. Darwish, Erwann Luais, Bin Guan, Jason Brian Harper, J Justin Gooding Jan 2011

Oxidative Acetylenic Coupling Reactions As A Surface Chemistry Tool, Simone Ciampi, Michael James, Nadim A. Darwish, Erwann Luais, Bin Guan, Jason Brian Harper, J Justin Gooding

Australian Institute for Innovative Materials - Papers

A novel method to prepare redox monolayers on silicon electrodes has been developed that employs CuI-catalyzed oxidative acetylenic coupling reactions for molecular electronic type applications. As the first case study, ethynylferrocene was covalently immobilized onto an acetylene-terminated monolayer on a Si(100) surface to give a 1,3-diyne (CC-CC-) linked redox assembly. The derivatization process requires no protection/de-protection steps, nor activation procedures. The effect of the conjugated diyne linkage on the rate of electron transfer between tethered ferrocenyl units and the silicon electrode is benchmarked against well-established "click" products (i.e. 1,2,3-triazole linkage). The surfaces, after each step, are characterized thoroughly using X-ray …


The Sensitivity Analysis Of A Mems Microphone With Different Membrane Diameters, Cheng-Ta Yang Dec 2010

The Sensitivity Analysis Of A Mems Microphone With Different Membrane Diameters, Cheng-Ta Yang

Journal of Marine Science and Technology

In MEMS capacitive microphone design, it is very critical to get highest yielding rate and sensitivity as the two major factors dominate structure design of microphone. The centralpost MEMS microphone is introduced in this paper to differentiate from traditional fixed membrane boundary microphone since the construction is simple and only few masks are required in the process so that the yielding can be greatly enhanced. Thus, it is necessary to find the relationship between the sensitivity and dimension of the diameter of the membrane. The main research steps described in this paper include using CoventorWarer to develop one analysis model …


Coupling Interaction Of Electromagnetic Wave In A Groove Doublet Configuration, Lan Ding, Jinsong Liu, Kejia Wang, Dong Wang Jan 2010

Coupling Interaction Of Electromagnetic Wave In A Groove Doublet Configuration, Lan Ding, Jinsong Liu, Kejia Wang, Dong Wang

Faculty of Engineering - Papers (Archive)

Based on the waveguide mode (WGM) method, coupling interaction of electromagnetic wave in a groove doublet configuration is studied. The formulation obtained by WGM method for a single groove [Prog. Electromagn. Res. 18, 1–17 (1998)] is extended to two grooves. By exploring the total scattered field of the configuration, coupling interaction ratios are defined to describe the interaction between grooves quantitatively. Since each groove in this groove doublet configuration is regarded as the basic unit, the effects of coupling interaction on the scattered fields of each groove can be investigated respectively. Numerical results show that an oscillatory behavior of …


Aperture Coupling And Penetration In Various Configurations, Jason Keen Dec 2008

Aperture Coupling And Penetration In Various Configurations, Jason Keen

All Dissertations

The problem of a slot in a perfectly conducting surface is addressed for a variety of configurations using both integral equation and transmission line techniques. The use of Bethe hole theory to model short slots is discussed and utilized where appropriate. Primary problems of discussion are a slot array, wires coupling through slots in a ground plane, and wires coupling through slots in a bent ground plane. Additionally, the use of the extended BLT formulation for incorporation of slot effects in a transmission line problem is addressed. In this manuscript, the work of Bethe is extended to include cross-aperture coupling …


Tooth Engagement Evaluation Of Involute Spline Couplings, Robert R. Robins Aug 2008

Tooth Engagement Evaluation Of Involute Spline Couplings, Robert R. Robins

Theses and Dissertations

Spline couplings are used in applications involving high torque; however, due to variations in teeth clearances, all teeth in spline couplings do not engage simultaneously, causing some of the teeth to carry a disproportionately large portion of the total load. Variations in tooth-to-tooth clearances mean the first pair of teeth to engage will carry more load and fail sooner. This has lead to an industry practice of designing splines around the criteria that only 25-50% of the teeth on a spline coupling will engage and carry the load, and the load is generally assumed to be uniformly distributed. This research …


Enhancement Of Polarization In A Spin-Orbit Coupling Quantum Wire With A Constriction, Chao Zhang, Zhi-Cheng Zhong, Dingping Li, Zhongshui Ma, Lei Chen, Junfeng Liu Jan 2007

Enhancement Of Polarization In A Spin-Orbit Coupling Quantum Wire With A Constriction, Chao Zhang, Zhi-Cheng Zhong, Dingping Li, Zhongshui Ma, Lei Chen, Junfeng Liu

Faculty of Engineering - Papers (Archive)

We investigate the enhancement of spin polarization in a quantum wire in the presence of a constriction and a spin-orbit coupling segment. It is shown that the spin-filtering effect is significantly heightened in comparison with the configuration without the constriction. It is understood in the studies that the constriction structure plays a critical role in enhancing the spin filtering by means of confining the incident electrons to occupy one channel only while the outgoing electrons occupy two channels. The enhancement of spin filtering has also been analyzed within the perturbation theory. Because the spin polarization arises mainly from the scattering …


Gate-Tunable Ruderman-Kittel-Kasuya-Yosida Interaction Mediated By Low-Dimensional Electrons With Rashba Spin-Orbit Coupling, Pin Lyu, Ning-Ning Liu, Chao Zhang Jan 2007

Gate-Tunable Ruderman-Kittel-Kasuya-Yosida Interaction Mediated By Low-Dimensional Electrons With Rashba Spin-Orbit Coupling, Pin Lyu, Ning-Ning Liu, Chao Zhang

Faculty of Engineering - Papers (Archive)

The gate-controllable Ruderman-Kittel-Kasuya-Yosida RKKY magnetic interaction between themagnetic impurities embedded in one- and two-dimensional electron gas in the presence of Rashbaspin-orbit coupling was analyzed theoretically. By using the eigenfunctions of the single-particleRashba Hamiltonian as the basis of second quantization, we derived the RKKY interaction by fullytaking into account the spin-orbit interaction. The dependence of the RKKY magnetic interaction onthe Rashba spin-orbit coupling strength was obtained numerically. Our results clearly indicate thatthe RKKY interaction can be significantly modified by an applied voltage via the Rashba spin-orbitcoupling.


Application Of Chip-Level Emc In Automotive Product Design, Kuifeng Hu, H. Weng, Daryl G. Beetner, David Pommerenke, James L. Drewniak, K. Lavery, Jason Whiles Aug 2006

Application Of Chip-Level Emc In Automotive Product Design, Kuifeng Hu, H. Weng, Daryl G. Beetner, David Pommerenke, James L. Drewniak, K. Lavery, Jason Whiles

Electrical and Computer Engineering Faculty Research & Creative Works

Integrated circuits (ICs) are often the source of the high-frequency noise that drives electromagnetic emissions from electronic products. A case study is presented where emissions from a printed circuit board containing an automotive microcontroller are reduced significantly through analysis of the coupling mechanisms from the chip to the board and attached cables. Noise generated by the IC is explored through measurements in a semi-anechoic chamber and TEM cell, through near-field scans, and through modifications to the printed circuit board. Noise is driven by the IC through both power and I/O connections. Results show that a ferrite in series with I/O …


Analysis Of Complexity And Coupling Metrics Of Subsystems In Large Scale Software Systems, Harish Ramakrishnan Jan 2006

Analysis Of Complexity And Coupling Metrics Of Subsystems In Large Scale Software Systems, Harish Ramakrishnan

Electronic Theses and Dissertations

Dealing with the complexity of large-scale systems can be a challenge for even the most experienced software architects and developers. Large-scale software systems can contain millions of elements, which interact to achieve the system functionality. Managing and representing the complexity involved in the interaction of these elements is a difficult task. We propose an approach for analyzing the reusability, maintainability and complexity of such a complex large-scale software system. Reducing the dependencies between the subsystems increase the reusability and decrease the efforts needed to maintain the system thus reducing the complexity of the system. Coupling is an attribute that summarizes …


Coupling Of Hydrodynamic And Wave Models For Storm Tide Simulations: A Case Study For Hurricane Floyd (1999), Yuji Funakoshi Jan 2006

Coupling Of Hydrodynamic And Wave Models For Storm Tide Simulations: A Case Study For Hurricane Floyd (1999), Yuji Funakoshi

Electronic Theses and Dissertations

This dissertation presents the development of a two-dimensional St. Johns River model and the coupling of hydrodynamic and wave models for the simulation of storm tides. The hydrodynamic model employed for calculating tides and surges is ADCIRC-2DDI (ADvanced CIRCulation Model for Shelves, Coasts and Estuaries, Two-Dimensional Depth Integrated) developed by Luettich et al. (1992). The finite element based model solves the fully nonlinear shallow water equations in the generalized wave continuity form. Hydrodynamic applications are operated with the following forcings: 1) astronomical tides, 2) inflows from tributaries, 3) meteorological effects (winds and pressure), and 4) waves (wind-induced waves). The wave …


Preliminary Study On The Impact Of Impingement On The Effectiveness Of Film Cooling In The Presence Of Gas Path Pressure Gradient, Anil Peravali Jan 2006

Preliminary Study On The Impact Of Impingement On The Effectiveness Of Film Cooling In The Presence Of Gas Path Pressure Gradient, Anil Peravali

Electronic Theses and Dissertations

Impingement is the most commonly used method of cooling in the hot stages of gas turbines. This is often combined with film cooling to further increase the cooling performance. The mainstream flow where in the coolant films discharge often has large stream wise pressure variations. All existing studies on coupled film and impingement cooling concentrated on the effect of the film depletion on the impingement heat transfer. This study investigates the impact of impingement on film cooling, where the jets impinging on a flat plate are depleted through arrays of film cooling holes in the presence of pressure gradient in …


Coupling Between Differential Signals And The Dc Power-Bus In Multilayer Pcbs, Chen Wang, Marco Leone, James L. Drewniak, Antonio Orlandi May 2005

Coupling Between Differential Signals And The Dc Power-Bus In Multilayer Pcbs, Chen Wang, Marco Leone, James L. Drewniak, Antonio Orlandi

Electrical and Computer Engineering Faculty Research & Creative Works

Differential and common-mode transfer impedances are proposed herein to analyze noise coupled to (from) the dc power-bus from (to) via transitions in differential signals. Expressions for the two transfer impedances in terms of conventional single-ended transfer impedances are derived and verified through measurements, full-wave finite-difference time-domain (FDTD) simulations and an analytical cavity model. Some properties of the differential and common-mode transfer impedances are investigated to facilitate engineering design. The impact of signal current imbalances on power-bus noise and the benefit of differential signals as compared to single-ended signals are quantified.


Traces In Proximity To Gaps In Return Planes, Todd H. Hubing, Thomas Van Doren, Theodore M. Zeeff Jan 2005

Traces In Proximity To Gaps In Return Planes, Todd H. Hubing, Thomas Van Doren, Theodore M. Zeeff

Electrical and Computer Engineering Faculty Research & Creative Works

Coupling between circuitry on printed circuit boards can be mitigated by a variety of well-known techniques. One such technique is to isolate circuitry in different areas of the printed circuit board by strategically placing a gap in the signal return plane. However, this technique is only effective at reducing common-impedance coupling, which is generally not a significant coupling mechanism at frequencies above 1 MHz. This paper investigates the effect of a gap located between and parallel to adjacent microstrip traces. The effect of the gap on the mutual inductance and mutual capacitance is evaluated. Laboratory measurements and numerical simulations show …


Thermodynamics And Bioenergetics, Yaşar Demirel, Stanley I. Sandler Mar 2002

Thermodynamics And Bioenergetics, Yaşar Demirel, Stanley I. Sandler

Papers in Thermal Mechanics

Bioenergetics is concerned with the energy conservation and conversion processes in a living cell, particularly in the inner membrane of the mitochondrion. This review summarizes the role of thermodynamics in understanding the coupling between the chemical reactions and the transport of substances in bioenergetics. Thermodynamics has the advantages of identifying possible pathways, providing a measure of the efficiency of energy conversion, and of the coupling between various processes without requiring a detailed knowledge of the underlying mechanisms. In the last five decades, various new approaches in thermodynamics, non-equilibrium thermodynamics and network thermodynamics have been developed to understand the transport and …