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Mechanical Engineering

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2007

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Full-Text Articles in Engineering

Test 1905: John Deere 5603 Diesel 12-Speed, Nebraska Tractor Test Lab Jan 2007

Test 1905: John Deere 5603 Diesel 12-Speed, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA

The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data.

EXPLANATION OF THE TEST PROCEDURES

Purpose

The purpose of …


Test 1906: John Deere 5625 Diesel 9-Speed, Nebraska Tractor Test Lab Jan 2007

Test 1906: John Deere 5625 Diesel 9-Speed, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA

The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data.

EXPLANATION OF THE TEST PROCEDURES

Purpose

The purpose of …


Test 1908: Case-Ih Steiger 380 And 385 Diesel 16-Speed Also Case-Ih Stx 380 Diesel 16-Speed, Nebraska Tractor Test Lab Jan 2007

Test 1908: Case-Ih Steiger 380 And 385 Diesel 16-Speed Also Case-Ih Stx 380 Diesel 16-Speed, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA

The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data.

EXPLANATION OF THE TEST PROCEDURES

Purpose

The purpose of …


Test 1909: Case-Ih Steiger 430 And 435 Diesel 16-Speed Also Case-Ih Stx 430 Diesel 16-Speed, Nebraska Tractor Test Lab Jan 2007

Test 1909: Case-Ih Steiger 430 And 435 Diesel 16-Speed Also Case-Ih Stx 430 Diesel 16-Speed, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA

The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data.

EXPLANATION OF THE TEST PROCEDURES

Purpose

The purpose of …


Method And System For Far-Field Microscopy To Exceeding Diffraction-Limit Resolution, C. Ya, Hai-Lung Tsai Jan 2007

Method And System For Far-Field Microscopy To Exceeding Diffraction-Limit Resolution, C. Ya, Hai-Lung Tsai

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The bio-sample (e.g., a live cell) is labeled with a proper number of nanoparticles. Each nanoparticle is pre-co-doped with a controlled ratio of fluorophore donors and acceptors. Two laser pulses are applied to the bio-sample. The first laser pulse has a center wavelength near the peak of absorption spectrum of acceptors. The intensity of first laser pulse is adjusted such that FRET saturation occurs near the center of the focal spot. The focal spot of the first laser pulse is a diffraction-limited Airy disk that has the highest laser intensity in the center of the focal spot. The second laser …


A Two-Layer Composite Model Of The Vocal Fol Lamina Propria For Fundamental Frequency Regulation, Kai Zhang, Thomas Siegmund, Roger W. Chan Jan 2007

A Two-Layer Composite Model Of The Vocal Fol Lamina Propria For Fundamental Frequency Regulation, Kai Zhang, Thomas Siegmund, Roger W. Chan

School of Mechanical Engineering Faculty Publications

No abstract provided.


Neural Network Controller Development And Implementation For Spark Ignition Engines With High Egr Levels, Jonathan B. Vance, Atmika Singh, Brian C. Kaul, Jagannathan Sarangapani, J. A. Drallmeier Jan 2007

Neural Network Controller Development And Implementation For Spark Ignition Engines With High Egr Levels, Jonathan B. Vance, Atmika Singh, Brian C. Kaul, Jagannathan Sarangapani, J. A. Drallmeier

Electrical and Computer Engineering Faculty Research & Creative Works

Past research has shown substantial reductions in the oxides of nitrogen (NOx) concentrations by using 10% -25% exhaust gas recirculation (EGR) in spark ignition (SI) engines (see Dudek and Sain, 1989). However, under high EGR levels, the engine exhibits strong cyclic dispersion in heat release which may lead to instability and unsatisfactory performance preventing commercial engines to operate with high EGR levels. A neural network (NN)-based output feedback controller is developed to reduce cyclic variation in the heat release under high levels of EGR even when the engine dynamics are unknown by using fuel as the control input. A separate …


Near Optimal Output-Feedback Control Of Nonlinear Discrete-Time Systems In Nonstrict Feedback Form With Application To Engines, Peter Shih, Brian C. Kaul, Jagannathan Sarangapani, J. A. Drallmeier Jan 2007

Near Optimal Output-Feedback Control Of Nonlinear Discrete-Time Systems In Nonstrict Feedback Form With Application To Engines, Peter Shih, Brian C. Kaul, Jagannathan Sarangapani, J. A. Drallmeier

Electrical and Computer Engineering Faculty Research & Creative Works

A novel reinforcement-learning based output-adaptive neural network (NN) controller, also referred as the adaptive-critic NN controller, is developed to track a desired trajectory for a class of complex nonlinear discrete-time systems in the presence of bounded and unknown disturbances. The controller includes an observer for estimating states and the outputs, critic, and two action NNs for generating virtual, and actual control inputs. The critic approximates certain strategic utility function and the action NNs are used to minimize both the strategic utility function and their outputs. All NN weights adapt online towards minimization of a performance index, utilizing gradient-descent based rule. …


Thermal Control Of An Occupied Room: Investigating The Use Of Carbon Dioxide Concentration As An Auxiliary Control Variable, Kevin O'Connell, Aidan O'Dwyer Jan 2007

Thermal Control Of An Occupied Room: Investigating The Use Of Carbon Dioxide Concentration As An Auxiliary Control Variable, Kevin O'Connell, Aidan O'Dwyer

Conference papers

This paper details the theoretical and experimental work done in the examination of the relationship between human generated carbon dioxide concentration and temperature rise in an occupied room. Generation of carbon dioxide by humans is linked to metabolic rate and heat generation. Therefore, carbon dioxide concentration may be used as an indicator of occupancy in a room. Typically, a heating control system will react slowly to changes in room occupancy if temperature is used as the process variable. The aim of the work was to establish if carbon dioxide concentration in the space could be used as an auxiliary control …


Accelerated Testing Method For Pem Fuel Cell Based Uninterrupted Power Supply Systems, Xinyu Huang, Xiaofeng Wang Jan 2007

Accelerated Testing Method For Pem Fuel Cell Based Uninterrupted Power Supply Systems, Xinyu Huang, Xiaofeng Wang

Faculty Publications

Proton exchange membrane fuel cell based power systems are on the verge of commercialization for a number of niche applications where batteries are traditionally used. Uninterrupted power supply (UPS) for wireless communication towers and broadband network relay utilities is one of the targeted application of fuel cell power systems with capacity ranging from one to serveral kilowatts. It is believed that fuel cell based UPS systems can offer considerable advantage when extended backup time is desirable. In order to replace the well-known battery based UPS systems, the reliability and perofrmance of fuel cell based UPS system need to be thoroughly …


Fracture Toughness Of Ceramic Moulds For Investment Casting With Ice Patterns, Qingbin Liu, Ming-Chuan Leu, Von Richards Jan 2007

Fracture Toughness Of Ceramic Moulds For Investment Casting With Ice Patterns, Qingbin Liu, Ming-Chuan Leu, Von Richards

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Ice patterns can be used to make ceramic investment moulds for metal castings. Owing to the characteristics of ice, the ceramic mould must be made at subzero temperatures and consequently, requires a different formulation than shells built at room temperature. Success of this process depends greatly on the fracture toughness of mould materials. The present paper describes the experimental results of fracture toughness of mould materials processed from different compositions. The Taguchi method was used to reduce the trial runs. The parameters considered included the ratio of fibre containing fused silica and aluminosilicate powders, the volume of binder and the …


Product Family Design Knowledge Representation, Aggregation, Reuse, And Analysis, Jyotirmaya Nanda, Henri Thevenot, Timothy W. Simpson, Robert B. Stone, Matt R. Bohm, Steven B. Shooter Jan 2007

Product Family Design Knowledge Representation, Aggregation, Reuse, And Analysis, Jyotirmaya Nanda, Henri Thevenot, Timothy W. Simpson, Robert B. Stone, Matt R. Bohm, Steven B. Shooter

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A flexible information model for systematic development and deployment of product families during all phases of the product realization process is crucial for product-oriented organizations. In current practice, information captured while designing products in a family is often incomplete, unstructured, and is mostly proprietary in nature, making it difficult to index, search, refine, reuse, distribute, browse, aggregate, and analyze knowledge across heterogeneous organizational information systems. To this end, we propose a flexible knowledge management framework to capture, reorganize, and convert both linguistic and parametric product family design information into a unified network, which is called a networked bill of material …


Acoustic Emission Detection And Prediction Of Fatigue Crack Propagation In Composite Patch Repairs Using Neural Networks, Navdeep Singh, Navrag Singh, Anthony Chukwujekwu Okafor Jan 2007

Acoustic Emission Detection And Prediction Of Fatigue Crack Propagation In Composite Patch Repairs Using Neural Networks, Navdeep Singh, Navrag Singh, Anthony Chukwujekwu Okafor

Mechanical and Aerospace Engineering Faculty Research & Creative Works

An aircraft is subjected to severe structural and aerodynamic loads during its service life. These loads can cause damage or weakening of the structure especially for aging military and civilian aircraft, thereby affecting its load carrying capabilities. Hence composite patch repairs are increasingly used to repair damaged aircraft metallic structures to restore its structural efficiency. This paper presents the results of Acoustic Emission (AE) monitoring of crack propagation in 2024-T3 Clad aluminum panels repaired with adhesively bonded octagonal, single sided boron/epoxy composite patch under tension-tension fatigue loading. Crack propagation gages were used to monitor crack initiation. The identified AE sensor …


Simple Penning Ion Source For Laboratory Research And Development Applications, Joshua L. Rovey, Brandon P. Ruzic, Thomas J. Houlahan Jan 2007

Simple Penning Ion Source For Laboratory Research And Development Applications, Joshua L. Rovey, Brandon P. Ruzic, Thomas J. Houlahan

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A simple Penning ion generator (PIG) that can be easily fabricated with simple machining skills and standard laboratory accessories is described. The PIG source uses an iron cathode body, samarium cobalt permanent magnet, stainless steel anode, and iron cathode faceplate to generate a plasma discharge that yields a continuous 1 mA beam of positively charged hydrogen ions at 1 mTorr of pressure. This operating condition requires 5.4 kV and 32.4 W of power. Operation with helium is similar to hydrogen. The ion source is being designed and investigated for use in a sealed-tube neutron generator; however, this ion source is …


Optimal Neuro-Controller Synthesis For Impulse-Driven System, Xiaohua Wang, S. N. Balakrishnan Jan 2007

Optimal Neuro-Controller Synthesis For Impulse-Driven System, Xiaohua Wang, S. N. Balakrishnan

Mechanical and Aerospace Engineering Faculty Research & Creative Works

This paper presents a new controller design technique for systems driven with impulse inputs. Necessary conditions for optimal impulse control are derived. A neural network structure to solve the resulting equations is presented. The solution concepts are illustrated with a few example problems that exhibit increasing levels of difficulty. Two linear problems-one scalar and one vector-and a benchmark nonlinear problem-Van Der Pol oscillator-are used as case studies. Numerical results show the efficacy of the new solution process for impulse driven systems. Since the theoretical development and the design technique are free from restrictive assumptions, this technique is applicable to many …


Determination Of Laser Absorption Coefficients Of Gas Mixtures Using An Ab Initio Md Model, Zhi Liang, Hai-Lung Tsai, Lan Jiang Jan 2007

Determination Of Laser Absorption Coefficients Of Gas Mixtures Using An Ab Initio Md Model, Zhi Liang, Hai-Lung Tsai, Lan Jiang

Mechanical and Aerospace Engineering Faculty Research & Creative Works

In an Effort to Study the Laser Induced Dissociation of Gas Mixtures for an Ongoing Research Project on Diamond Thin Film Coating using Multiple Lasers, It is Necessary to Determine the Absorption Coefficient of Laser Energy by CO2 Gas. an Ab Initio Molecular Dynamics (AIMD) Model is Used to Determine the Laser Absorption Coefficient of CO2 Gas as a Function of Laser Wavelength and Gas Temperature. the Translational, Rotational, and Vibration Motions of Molecules Are All Taken into Account in Our Model. the Intra-Molecular Potential Energy is Obtained by Solving the Kohn-Sham Equation. the Projector-Augmented Wave (PAW) Exchange-Correlation Potential Function …


Thermal Effectiveness Characteristics Of Low Approach Indirect Evaporative Cooling Systems In Buildings, Ben Costelloe, Donal Finn Jan 2007

Thermal Effectiveness Characteristics Of Low Approach Indirect Evaporative Cooling Systems In Buildings, Ben Costelloe, Donal Finn

Articles

Meteorological enthalpy analysis of temperate and maritime climates above latitude 45°N suggests that the water-side evaporative cooling technique has considerable unrealised potential with contemporary “high temperature” building cooling systems—such as chilled ceilings and displacement ventilation. As low approach conditions are the key to exploiting the cooling potential of the ambient air, thermal performance at such conditions needs to be investigated. To address the research issues, an industrial scale test rig, based on a low approach open cooling tower and plate heat exchanger and designed to maximise evaporative cooling potential, has been constructed. The thermal effectiveness of such systems (as a …


Plasma Treatment Of Bulk Nb Surface In The Ar/Cl2 Discharge, M. Rašković, L. Vuskovic, S. Popovic, A.-M. Valente-Feliciano, L. Phillips Jan 2007

Plasma Treatment Of Bulk Nb Surface In The Ar/Cl2 Discharge, M. Rašković, L. Vuskovic, S. Popovic, A.-M. Valente-Feliciano, L. Phillips

Physics Faculty Publications

The preparation of the cavity walls has been one of the major challenges in the superconducting radio-frequency (SRF) accelerator technology. Therefore, constant research and development effort is devoted to develop surface preparation processes that will improve roughness and lower the level of impurities, like hydrogen or oxygen, embedded in bulk Nb, having in the same time reasonable etching rates. Plasma based surface modification provides an excellent opportunity to achieve these goals. We present Ar/Cl2 discharge treatment of bulk Nb where we achieved etching rates comparable to the rates obtained with the electropolishing method without introducing impurities in Nb. The …


Time-Economic Lifetime Assessment For High Performance Thermal Barrier Coating Systems, Marion Bartsch, Bernd Baufeld, S. Dalkilic, Iulian Mircea, K. Lambrinou, T. Leist, J. Yan, Anette M. Karlsson Jan 2007

Time-Economic Lifetime Assessment For High Performance Thermal Barrier Coating Systems, Marion Bartsch, Bernd Baufeld, S. Dalkilic, Iulian Mircea, K. Lambrinou, T. Leist, J. Yan, Anette M. Karlsson

Mechanical Engineering Faculty Publications

Strategies for time-economic lifetime assessment of thermal barrier coatings (TBC) in service are described and discussed on the basis of experimental results, achieved on material systems with coatings applied by electron beam physical vapour deposition. Service cycles for gas turbine blades have been simulated on specimens in thermo-mechanical fatigue tests, accelerating the fatigue processes by an increase of load frequency. Time dependent changes in the material system were imposed by a separate ageing, where the samples were pre-oxidized prior to the fatigue test. Results of thermo-mechanical fatigue tests on pre-aged and as-coated specimens gave evidence of interaction between fatigue and …


Robust Positively Invariant Cylinders In Constrained Variable Structure Control, Hanz Richter, Brian D. O'Dell, Eduardo A. Misawa Jan 2007

Robust Positively Invariant Cylinders In Constrained Variable Structure Control, Hanz Richter, Brian D. O'Dell, Eduardo A. Misawa

Mechanical Engineering Faculty Publications

This paper proposes the use of cylinders as primary invariant sets to be used in certain state-constrained control designs. Following the idea originally introduced by O'Dell, the primary invariant set is intersected with the state constraints to yield sets which retain the invariance under some conditions. Although several results presented here apply to fairly general nonlinear systems and primary invariant sets of any shape, the focus is on constrained sliding-mode control (SMC) using infinite cylinders as the primary invariant set. Their use is motivated by a coordinate transformation where the sliding motion is decoupled from the overall convergence to the …


Acl Injuries: Do We Know The Mechanisms?, Antonie J. Van Den Bogert, Scott G. Mclean Jan 2007

Acl Injuries: Do We Know The Mechanisms?, Antonie J. Van Den Bogert, Scott G. Mclean

Mechanical Engineering Faculty Publications

Injuries of the anterior cruciate ligament (ACL) remain a frequent occurrence in many sports activities. Recent research has identified risk factors, and prevention strategies are being developed based on these findings. There is, however, still a limited understanding of the actual injury mechanisms. In this presentation we will review the current knowledge on ACL injury mechanisms, and identify needs and opportunities for further research.


Solar Energy For Disaster Response Using Space Program Resources, Florida Solar Energy Center, William Young Jan 2007

Solar Energy For Disaster Response Using Space Program Resources, Florida Solar Energy Center, William Young

FSEC Energy Research Center®

Satellite pictures, solar radiation levels on the earth's surface, Global Positioning Satellites (GPS) and other space-related resources are available through the efforts of many people and organizations. Satellites' measurements of these resources can be integrated with resources on earth to assess damage from disasters and evaluate resources available to respond. Space-related resources are currently being used by the American Red Cross, the Federal Emergency Management Agency, county Emergency Managers and other organizations. The widest use is in evaluating utility resources and deploying them for repair and emergency power in response to a disaster. Today's use of state-of-the-art satellite and Geographic …