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2008

Electrical and Computer Engineering

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Full-Text Articles in Mechanical Engineering

تعيين عرض تختال در ورودي كوره هاي پيش گرم ناحيه نورد گرم مجتمع فولاد مباركه با استفاده از پردازش ديجيتال تصاوير, Eaman Alibeigi, Rasoul Amirfattahi, Masoud Harooni, Hamid Montazerolghaem Nov 2008

تعيين عرض تختال در ورودي كوره هاي پيش گرم ناحيه نورد گرم مجتمع فولاد مباركه با استفاده از پردازش ديجيتال تصاوير, Eaman Alibeigi, Rasoul Amirfattahi, Masoud Harooni, Hamid Montazerolghaem

Masoud Harooni

هر يك از تختال هاي توليد شده در بخش ريخته گري مداوم ناحيه فولاد سازي، پس از مارك زني و تعيين مشتري به يكي از دو صورت هوايي يا سيالي خنك شده و در زمان مقرر به وسيله غلطك هايي وارد كوره پيش گرم مي شوند. در اين مرحله، 1/6 mm تختال تا حرارت 1100 درجه سانتيگراد گرم شده و عمليات نورد گرم بر روي آن به منظور تهيه ورق فولاد با ضخامت صورت مي گيرد. تعيين دقيق مشخصات ابعادي تختال ها از جمله طول، عرض و ضخامت آنها قبل از ورود به كوره هاي پيش گرم و تطبيق ...


Homogeneous Dbd In N2: 1) Lif, Talif And Electrical Measurements, N. Gherardi, Et. Es-Sebbar, C. Sarra-Bourret, N. Naudé, F. Massines Oct 2008

Homogeneous Dbd In N2: 1) Lif, Talif And Electrical Measurements, N. Gherardi, Et. Es-Sebbar, C. Sarra-Bourret, N. Naudé, F. Massines

Dr. Et-touhami Es-sebbar

In this paper we compare two different discharges that can be obtained in a DBD configuration, that is to say the filamentary discharge (usual regime in atmospheric DBD) with the Atmospheric Pressure Townsend Discharge (APTD), which is a homogeneous regime obtained in nitrogen atmosphere. The aim is to help in the understanding of the processes which control the transition from one regime to the other. To do so, the discharge is characterized through electrical measurements, coupled with optical diagnostics among which Laser Induced Fluorescence (LIF) for radical density measurements. The influence of the addition of small quantities of additives on ...


Broadband Measurement Of Rate-Dependent Viscoelasticity At Nanoscale Using Scanning Probe Microscope: Poly(Dimethylsiloxane) Example, Zhonghua Xu, Kyongsoo Kim, Qingze Zou, Pranav Shrotriya Sep 2008

Broadband Measurement Of Rate-Dependent Viscoelasticity At Nanoscale Using Scanning Probe Microscope: Poly(Dimethylsiloxane) Example, Zhonghua Xu, Kyongsoo Kim, Qingze Zou, Pranav Shrotriya

Mechanical Engineering Publications

A control approach to achieve nanoscale broadband viscoelasticmeasurement using scanning probe microscope(SPM) is reported. Current SPM-based force measurement is too slow to measure rate-dependent phenomena, and large (temporal) measurement errors can be generated when the sample itself changes rapidly. The recently developed model-less inversion-based iterative control technique is used to eliminate the dynamics and hysteresis effects of the SPM hardware on the measurements, enabling rapid excitation and measurement of rate-dependent material properties. The approach is illustrated by the mechanical characterization of poly(dimethylsiloxane) over a broad frequency range of three orders of magnitude (∼1 Hz to 4.5 KHz).


Active Species Generation Of Homogeneous Dbd In N2: Experiment And Modelling, N. Gherardi, Et. Es-Sebbar, C. Sarra-Bourret, N. Naudé, F. Massines, D. Tzyganov, P. Ségur, S. Pancheshnyi Sep 2008

Active Species Generation Of Homogeneous Dbd In N2: Experiment And Modelling, N. Gherardi, Et. Es-Sebbar, C. Sarra-Bourret, N. Naudé, F. Massines, D. Tzyganov, P. Ségur, S. Pancheshnyi

Dr. Et-touhami Es-sebbar

No abstract provided.


A Heuristic Scheduling Scheme In Multiuser Ofdma Networks, Zheng Sun, Zhiqiang He, Ruochen Wang, Kai Niu Aug 2008

A Heuristic Scheduling Scheme In Multiuser Ofdma Networks, Zheng Sun, Zhiqiang He, Ruochen Wang, Kai Niu

Zheng Sun

Conventional heterogeneous-traffic scheduling schemes utilize zero-delay constraint for real-time services, which aims to minimize the average packet delay among real-time users. However, in light or moderate load networks this strategy is unnecessary and leads to low data throughput for non-real-time users. In this paper, we propose a heuristic scheduling scheme to solve this problem. The scheme measures and assigns scheduling priorities to both real-time and non-real-time users, and schedules the radio resources for the two user classes simultaneously. Simulation results show that the proposed scheme efficiently handles the heterogeneous-traffic scheduling with diverse QoS requirements and alleviates the unfairness between real-time ...


The Dependence Of Measured Modulation Error Ratio On Phase Noise, Ron D. Katznelson Aug 2008

The Dependence Of Measured Modulation Error Ratio On Phase Noise, Ron D. Katznelson

Ron D. Katznelson

This paper reviews the algorithms used by Vector Signal Analyzers to measure Modulation Error Ratio (MER) and derives the explicit functional dependence of measured MER on phase noise of digital transmitters. The modulation error model is introduced and the analytical expression for key estimated parameters required to obtain MER measure are derived. The essential elements of algorithms employed by MER measurement instruments to estimate amplitude scale, frequency offset, and initial phase intercept and the resulting MER are identified. The frequency response of the effective phase-noise rejection filtering action associated with a given measurement epoch is derived. It is shown that ...


Reinforcement Learning Based Dual-Control Methodology For Complex Nonlinear Discrete-Time Systems With Application To Spark Engine Egr Operation, Peter Shih, Brian C. Kaul, Jagannathan Sarangapani, J. A. Drallmeier Aug 2008

Reinforcement Learning Based Dual-Control Methodology For Complex Nonlinear Discrete-Time Systems With Application To Spark Engine Egr Operation, Peter Shih, Brian C. Kaul, Jagannathan Sarangapani, J. A. Drallmeier

Electrical and Computer Engineering Faculty Research & Creative Works

A novel reinforcement-learning-based dual-control methodology adaptive neural network (NN) controller is developed to deliver a desired tracking performance for a class of complex feedback nonlinear discrete-time systems, which consists of a second-order nonlinear discrete-time system in nonstrict feedback form and an affine nonlinear discrete-time system, in the presence of bounded and unknown disturbances. For example, the exhaust gas recirculation (EGR) operation of a spark ignition (SI) engine is modeled by using such a complex nonlinear discrete-time system. A dual-controller approach is undertaken where primary adaptive critic NN controller is designed for the nonstrict feedback nonlinear discrete-time system whereas the secondary ...


Abstracts, Review Of Progress In Quantitative Nondestructive Evaluation (Chicago, Il, July 20–25, 2008), Center For Nondestructive Evaluation, Iowa State University Jul 2008

Abstracts, Review Of Progress In Quantitative Nondestructive Evaluation (Chicago, Il, July 20–25, 2008), Center For Nondestructive Evaluation, Iowa State University

Review of Progress in Quantitative Nondestructive Evaluation

Abstracts of papers presented at the 2008 Review of Progress in Quantitative Nondestructive Evaluation (QNDE) conference held in Chicago, Illinois from July 20–25, 2008.


Surface Ion-Electron Recombination As The Main Source Of Atoms In Flowing N2 Dbd, D. Tsyganov, Et. Es-Sebbar, S. Pancheshnyi, N. Gherardi, P. Ségur, F. Massines Jul 2008

Surface Ion-Electron Recombination As The Main Source Of Atoms In Flowing N2 Dbd, D. Tsyganov, Et. Es-Sebbar, S. Pancheshnyi, N. Gherardi, P. Ségur, F. Massines

Dr. Et-touhami Es-sebbar

No abstract provided.


Talif Quantification Of Nitrogen Atoms Applied To Experimental Simulation Of Titan’S Atmosphere, Et. Es-Sebbar, Y. Benilan, E. Arzoumanian, M.-C. Gazeau Jul 2008

Talif Quantification Of Nitrogen Atoms Applied To Experimental Simulation Of Titan’S Atmosphere, Et. Es-Sebbar, Y. Benilan, E. Arzoumanian, M.-C. Gazeau

Dr. Et-touhami Es-sebbar

No abstract provided.


S.E.T.U.P., A New Program Of Representative Simulations Of Titan’S Atmosphere: Current Status, M-C. Gazeau, E. Arzoumanian, Y. Benilan, Et. Es-Sebbar, A. Jolly, S. Perrier, C. Romanzin Jul 2008

S.E.T.U.P., A New Program Of Representative Simulations Of Titan’S Atmosphere: Current Status, M-C. Gazeau, E. Arzoumanian, Y. Benilan, Et. Es-Sebbar, A. Jolly, S. Perrier, C. Romanzin

Dr. Et-touhami Es-sebbar

No abstract provided.


Comparison Of Townsend Dielectric Barrier Discharge In N2, N2/O2 And N2/N2o: Behavior And Density Of Radicals, F. Massines, Et. Es-Sebbar, N. Gherardi, N. Naudé, D. Tsyganov, P. Ségur, S. Pancheshnyi Jun 2008

Comparison Of Townsend Dielectric Barrier Discharge In N2, N2/O2 And N2/N2o: Behavior And Density Of Radicals, F. Massines, Et. Es-Sebbar, N. Gherardi, N. Naudé, D. Tsyganov, P. Ségur, S. Pancheshnyi

Dr. Et-touhami Es-sebbar

No abstract provided.


Dual Beam Actuation Of Piezoelectric Aln Rf Mems Switches Integrated With Aln Contour-Mode Resonators, Nipun Sinha, Rashed Mahamameed, Chengjie Zuo, Marcelo B. Pisani, Carlos R. Perez, Gianluca Piazza Jun 2008

Dual Beam Actuation Of Piezoelectric Aln Rf Mems Switches Integrated With Aln Contour-Mode Resonators, Nipun Sinha, Rashed Mahamameed, Chengjie Zuo, Marcelo B. Pisani, Carlos R. Perez, Gianluca Piazza

Nipun Sinha

This work reports on piezoelectric Aluminum Nitride (AlN) based dual-beam RF MEMS switches that have been monolithically integrated with AlN contour-mode resonators. The dual-beam switch design presented in this paper intrinsically compensates for the residual stress in the deposited films, requires low actuation voltage (5-20 V), facilitates active pull-off to open the switch and fast switching times (1 to 2 µsec). This work also presents the combined response (cascaded S-parameters) of a resonator and a switch that were co-fabricated on the same substrate. The response shows that the resonator can be effectively turned on and off by the switch. A ...


Dual Beam Actuation Of Piezoelectric Aln Rf Mems Switches Integrated With Aln Contour-Mode Resonators, Nipun Sinha, Rashed Mahamameed, Chengjie Zuo, Marcelo B. Pisani, Carlos R. Perez, Gianluca Piazza Jun 2008

Dual Beam Actuation Of Piezoelectric Aln Rf Mems Switches Integrated With Aln Contour-Mode Resonators, Nipun Sinha, Rashed Mahamameed, Chengjie Zuo, Marcelo B. Pisani, Carlos R. Perez, Gianluca Piazza

Marcelo B Pisani

This work reports on piezoelectric Aluminum Nitride (AlN) based dual-beam RF MEMS switches that have been monolithically integrated with AlN contour-mode resonators. The dual-beam switch design presented in this paper intrinsically compensates for the residual stress in the deposited films, requires low actuation voltage (5-20 V), facilitates active pull-off to open the switch and fast switching times (1 to 2 µsec). This work also presents the combined response (cascaded S-parameters) of a resonator and a switch that were co-fabricated on the same substrate. The response shows that the resonator can be effectively turned on and off by the switch. A ...


College Of Engineering Senior Design Competition Spring 2008, University Of Nevada, Las Vegas May 2008

College Of Engineering Senior Design Competition Spring 2008, University Of Nevada, Las Vegas

Senior Projects (COE)

Part of every UNLV engineering student’s academic experience, the senior design project stimulates engineering innovation and entrepreneurship. Each student in their senior year chooses, plans, designs, and prototypes a product in this required element of the curriculum. A capstone to the student’s educational career, the senior design project encourages the student to use everything learned in the engineering program to create a practical, real world solution to an engineering challenge.

The senior design competition helps to focus the senior students in increasing the quality and potential for commercial application for their design projects. Judges from local industry evaluate ...


A Review Of Variable Valve Timing Devices, Paul Shelton May 2008

A Review Of Variable Valve Timing Devices, Paul Shelton

Mechanical Engineering Undergraduate Honors Theses

Variable valve timing (VVT) has evolved from simple, manual controlled engine management to automatic, electronic works of engineering. Starting from the need for more power and extending into fuel efficiency and low emissions, VVT has evolved from the constant changing of needs. This paper summarizes various devices used to control the timing of valves from the early 1920s up until 2007.


Criteria On Utility Designing Of Convex Optimization In Fdma Networks, Zheng Sun, Wenjun Xu, Zhiqiang He, Kai Niu Apr 2008

Criteria On Utility Designing Of Convex Optimization In Fdma Networks, Zheng Sun, Wenjun Xu, Zhiqiang He, Kai Niu

Zheng Sun

In this paper, we investigate the network utility maximization problem in FDMA systems. We summarize with a suite of criteria on designing utility functions so as to achieve the global optimization convex. After proposing the general form of the utility functions, we present examples of commonly used utility function forms that are consistent with the criteria proposed in this paper, which include the well-known proportional fairness function and the sigmoidal-like functions. In the second part of this paper, we use numerical results to demonstrate a case study based on the criteria mentioned above, which deals with the subcarrier scheduling problem ...


Proceedings From Scientific Conference On Green Energy And It, Dr. Erik Dahlquist Mar 2008

Proceedings From Scientific Conference On Green Energy And It, Dr. Erik Dahlquist

Dr. Erik Dahlquist

This conference is part of the annual Energitinget, a national arena for energy in Sweden, with some 2500 participants. The focus with this session is to give a forum for researchers to present scientific results, and also to discuss these with other researchers. It contains papers in the area of Energy and IT as well as Green energy generally


Output Feedback Controller For Operation Of Spark Ignition Engines At Lean Conditions Using Neural Networks, Jonathan B. Vance, Brian C. Kaul, Jagannathan Sarangapani, J. A. Drallmeier Mar 2008

Output Feedback Controller For Operation Of Spark Ignition Engines At Lean Conditions Using Neural Networks, Jonathan B. Vance, Brian C. Kaul, Jagannathan Sarangapani, J. A. Drallmeier

Electrical and Computer Engineering Faculty Research & Creative Works

Spark ignition (SI) engines operating at very lean conditions demonstrate significant nonlinear behavior by exhibiting cycle-to-cycle bifurcation of heat release. Past literature suggests that operating an engine under such lean conditions can significantly reduce NO emissions by as much as 30% and improve fuel efficiency by as much as 5%-10%. At lean conditions, the heat release per engine cycle is not close to constant, as it is when these engines operate under stoichiometric conditions where the equivalence ratio is 1.0. A neural network controller employing output feedback has shown ability in simulation to reduce the nonlinear cyclic dispersion ...


Laboratory Experiments As Support To The Built Up Of Titan’S Theoretical Models And Interpretation Of Cassini-Huygens Data, M-C. Gazeau, Y Benilan, Et. Es-Sebbar, T. Ferradaz, E. Hébrard, A. Jolly, F. Raulin, C. Romanzin, J-C. Guillemin, C. Berteloite, A. Canosa, S. D. Le Picard, Ian R. Sims Feb 2008

Laboratory Experiments As Support To The Built Up Of Titan’S Theoretical Models And Interpretation Of Cassini-Huygens Data, M-C. Gazeau, Y Benilan, Et. Es-Sebbar, T. Ferradaz, E. Hébrard, A. Jolly, F. Raulin, C. Romanzin, J-C. Guillemin, C. Berteloite, A. Canosa, S. D. Le Picard, Ian R. Sims

Dr. Et-touhami Es-sebbar

No abstract provided.


Use Of Modeling And Simulation In Pulp And, Dr. Erik Dahlquist Jan 2008

Use Of Modeling And Simulation In Pulp And, Dr. Erik Dahlquist

Dr. Erik Dahlquist

The book is a handbook for operators and process engineers in primarily pulp and paper industry, but also other process industries about how to utilise simulation as a tool for enhanced process operations. The book has been written as part of a EU COST action on Process Simulation, with 14 countries and 50 researchers and process industry representatives involved.


High Ppeed Circuit Techniques For Network Intrusion Detection Systems (Nids), Ajay Mohan Mahajan Jan 2008

High Ppeed Circuit Techniques For Network Intrusion Detection Systems (Nids), Ajay Mohan Mahajan

Mechanical Engineering Faculty Research

No abstract provided.


Response Characterization Of Electroactive Polymers As Mechanical Sensors, G. Alici, Geoffrey M. Spinks, J. D. Madden, Y. Wu, G G. Wallace Jan 2008

Response Characterization Of Electroactive Polymers As Mechanical Sensors, G. Alici, Geoffrey M. Spinks, J. D. Madden, Y. Wu, G G. Wallace

Faculty of Engineering - Papers (Archive)

The characterization of the dynamic response (including transfer function identification) of trilayer polypyrrole (PPy) type conducting polymer sensors is presented. The sensor was built like a cantilever beam with the free end stimulated through a mechanical lever system, which provided displacement inputs. The voltage generated and current passing between the two outer PPy layers as a result of the input was measured to model the output/input behavior of the sensors based on their experimental current/displacement and voltage/displacement frequency responses. We specifically targeted the low-frequency behavior of the sensor as it is a relatively slowsystem. Experimental transfer function ...


Stereolithography Of Poly(Ethylene Glycol) Hydrogels With Application In Tissue Engineering As Peripheral Nerve Regeneration Scaffolds, Karina Arcaute Jan 2008

Stereolithography Of Poly(Ethylene Glycol) Hydrogels With Application In Tissue Engineering As Peripheral Nerve Regeneration Scaffolds, Karina Arcaute

Open Access Theses & Dissertations

In recent years, rapid prototyping (RP) technologies initially developed to create prototypes prior to production for the automotive, aerospace, and other industries, have found applications in tissue engineering (TE). Several different RP technologies are being used to fabricate biocompatible 3D structures with controlled micro- and macro-scale characteristics. The focus of this research was to explore the capabilities of the RP technology, stereolithography (SL), for creating complex, 3D scaffolds with applications in TE using a photocrosslinkable biopolymer, poly(ethylene glycol) (PEG). The primary objective was to create an implantable multi-lumen nerve guidance conduit (NGC) for the regeneration of peripheral nerves.

Studies ...


Energy Efficiency Enhancements To A Low Energy High Performance Building, Joel Clifton Logan Jan 2008

Energy Efficiency Enhancements To A Low Energy High Performance Building, Joel Clifton Logan

Retrospective Theses and Dissertations

This report discusses energy efficiency enhancements made to a low energy, high performance office building. The building studied is the Iowa Association of Municipal Utilities headquarters located in Ankeny, Iowa, just north of Des Moines. Monitoring the energy use of the building for over six years has revealed that it has an average annual site energy use of 29,300 Btu/ft2. This is 68% less energy than that used by the average U.S. office building and 74% less energy than the average office building in climate zone 2, the location of Ankeny.;Three areas of energy use were ...


Techno-Economic Evaluations Of Biofuel Technologies, Mark Mba Wright Jan 2008

Techno-Economic Evaluations Of Biofuel Technologies, Mark Mba Wright

Retrospective Theses and Dissertations

This thesis consists of three related techno-economic studies of biofuels production. The major purpose of these studies is to establish meaningful comparisons between different technologies for producing biofuels and explore scenarios leading to optimal biofuel costs.;Three journal papers have been published in Biofuels, Bioprocessing, and Biorefining from the results of this study: "Comparative economics of biorefineries based on the biochemical and thermochemical platforms", "Establishing the optimal size of different kinds of biorefineries", and "Distributed processing of biomass to bio-oil for subsequent production of Fischer-Tropsch liquids".;Several major conclusions were drawn from this study. Advanced biorefineries will require capital investments ...


The Evaluation Of Maize Genotypes For Potential Use In Cellulosic Ethanol Production, Krystal Marie Kirkpatrick Jan 2008

The Evaluation Of Maize Genotypes For Potential Use In Cellulosic Ethanol Production, Krystal Marie Kirkpatrick

Retrospective Theses and Dissertations

Corn stover represents a potential lignocellulosic feedstock that may benefit the emerging cellulosic ethanol industry. This study was conducted to determine dry matter yield and quality characteristics of maize stover, cob, and husk plant fractions, and to make predictions of potential ethanol yields. Detergent fiber predictions were made for each plant fraction using near infrared reflectance spectroscopy (NIRS). Predicted values were used to determine ethanol potential using a modified version of the National Renewable Energy Lab (NREL) theoretical ethanol yield calculator. Although significant, not as much variation was present among genotypes and plant fractions for chemical composition as for dry ...


Light-Trapping Enhancement In Thin Film Solar Cells With Photonic Crystals, Dayu Zhou Jan 2008

Light-Trapping Enhancement In Thin Film Solar Cells With Photonic Crystals, Dayu Zhou

Retrospective Theses and Dissertations

Photovoltaics (or solar cell) has been an active area for research and development, driven by the world's constantly increasing needs for power. Among the current solar technologies, thin film solar cell promises lower cost, but at the expense of lower power conversion efficiency. The efficiency of thin film solar cell can be improved using light confinement schemes commonly referred to as light-trapping. In this thesis, we develop novel light-trapping schemes utilizing photonic crystals (PCs). The optical modeling is performed with a rigorous scattering matrix approach, where Maxwell's equations are solved in Fourier space, and simulations are carried out ...


A Static Analysis Of Maximum Wind Penetration In Iowa And A Dynamic Assessment Of Frequency Response In Wind Turbine Types, Eknath Vittal Jan 2008

A Static Analysis Of Maximum Wind Penetration In Iowa And A Dynamic Assessment Of Frequency Response In Wind Turbine Types, Eknath Vittal

Retrospective Theses and Dissertations

As the energy industry moves into the 21st century the use and research into renewable resources has expanded significantly. Whether it is wind, biomass, or solar, the industry is seeking ways to breakthrough and integrate the newest technologies into their power systems. Wind energy, in particular, has seen significant expansion since the 1980's, with generating capability of wind turbines increasing dramatically from 50 kW to nearly 5 MW presently. Seeking to introduce larger levels of wind generation in the Iowa electricity system, the goal of this thesis was to: First, determine the maximum wind penetration level of the existing ...


Decision Making Limitations From Communication Barriers In Government Structures In Chinese Rural Energy Projects, Nathan Gregory Johnson Jan 2008

Decision Making Limitations From Communication Barriers In Government Structures In Chinese Rural Energy Projects, Nathan Gregory Johnson

Retrospective Theses and Dissertations

Field research was conducted in the Li Cheng District (about 1,200 km 2) of Shan Dong Province. Data collection occurred during a two-week period in July 2006. At that time, seven villages represented all relevant sites in the district that contained gasification technologies. Small-group interviews with village leaders, station managers, and community members were conducted locally. Contact with external government agencies and technology scientists completed the set of potential stakeholders.;This study analyzes the failure of state-owned energy development initiatives in China. Communication barriers in bureaucratic structures and culturally prescribed patterns of interaction were revealed as inhibiting information transfer ...