Engineering Commons^™

A Precision Instrument For Research Into Nanolithographic Techniques Using Field-Emitted Electron Beams, King-Fu Hii

University of Kentucky Doctoral Dissertations

Nanomanufacturing is an active research area in academia and industry due to the ever-growing demands for precision surface modifications of thin films or substrates with nanoscale features. Conventional lithographic techniques face many challenges as they approach their fundamental limits. Consequently, new nanomanufacturing tools, fabrication techniques, and precision instruments are being explored and developed to meet these challenges. It has been hypothesized that direct-write nanolithography might be achieved by using a field-emitted electron beam for nanomachining. This dissertation moves this research one step closer by developing a precision instrument that can enable the integration of direct-write nanolithography by a field-emitted electron …

An Investigation Of Size Effects On Thin Sheet Formability For Microforming Applications, Nasr Abdelrahman Shuaib

University of Kentucky Doctoral Dissertations

The increasing demand for powerful miniaturized products for all industrial applications has prompted the industry to develop new and innovative manufacturing processes to fabricate miniature parts. One of the major challenges facing the industry is the dynamic market which requires continuous improvements in design and fabrication techniques. This means providing products with complex features while sustaining high functionality. As a result, microfabrication has gained a wide interest as the technology of the future, where tabletop machine systems exist. Microforming processes have the capability of achieving mass production while minimizing material waste. Microforming techniques can produce net-shape products with intricacy in …

Uncertainty Analysis And Sensitivity Analysis For Multidisciplinary Systems Design, Jia Guo

Doctoral Dissertations

"The objective of this research is to quantify the impact of both aleatory and epistemic uncertainties on performances of multidisciplinary systems. Aleatory uncertainty comes from the inherent uncertain nature and epistemic uncertainty comes from the lack of knowledge. Although intensive research has been conducted on aleatory uncertainty, few studies on epistemic uncertainty have been reported. In this work, the two types of uncertainty are analyzed. Aleatory uncertainty is modeled by probability distributions while epistemic uncertainty is modeled by intervals. Probabilistic analysis (PA) and interval analysis (IA) are integrated to capture the effect of the two types of uncertainty. The First …

Integrated Process Planning For A Hybrid Manufacturing System, Lan Ren

Doctoral Dissertations

"A hybrid manufacturing system integrated CNC machining and laser-aided layered deposition and achieves the benefits of both processes. In this dissertation, an integrated process planning framework which aims to automate the hybrid manufacturing process is investigated. Critical components of the process planning, including 3D spatial decomposition of the CAD model, improvement of the toolpath generation pattern, repairing strategies using a hybrid manufacturing system, etc., are discussed"--Abstract, page iv.

Modeling And Rendering For Development Of A Virtual Bone Surgery System, Qiang Niu

Doctoral Dissertations

"A virtual bone surgery system is developed to provide the potential of a realistic, safe, and controllable environment for surgical education. It can be used for training in orthopedic surgery, as well as for planning and rehearsal of bone surgery procedures...Using the developed system, the user can perform virtual bone surgery by simultaneously "seeing" bone material removal through a graphic display device, "feeling" the force via a haptic deice, and "hearing" the sound of tool-bone interaction"--Abstract, page iii.

Individual-Based Artificial Ecosystems For Design And Optimization, Shivakar Vulli

Masters Theses

"Individual-based modeling has gained popularity over the last decade, mainly due to the paradigm's proven ability to address a variety of problems seen in many disciplines, including modeling complex systems from bottom-up, providing relationship between component level and system level parameters, and discovering the emergence of system-level behaviors from simple component level interactions. Availability of computational power to run simulation models with thousands to millions of agents is another driving force in the widespread adoption of individual-based modeling. This thesis proposes an individual-based modeling approach for solving engineering design and optimization problems using artificial ecosystems"--Abstract, page iii.

Fatigue Analysis Of An Inline Skate Axel, Garrett Hansen, Mike Woizeschke

The Journal of Undergraduate Research

In this paper, an inline skate axel is analyzed based on fatigue and economic principles for four different materials. The loading scenario on the axel of the inline skate is derived and broken down to a maximum shear stress that must be less than the maximum fatigue stress of the axel material. A fatigue analysis using Goodman line diagrams is applied to axels made of aluminum, titanium, nylon, and PVC. The material strengths are then compared to the loading requirements and determined whether they would be sufficient for an axel material. Finally, the prices are compared to verify the selection …

A New Method Of Synthesizing Black Birnessite Nanoparticles: From Brown To Black Birnessite With Nanostructures, Shizhi Qian, Marcos A. Cheney, Pradip K. Bhowmik, Sang W. Joo, Wensheng Hou, Joseph M. Okoh

Mechanical Engineering Faculty Research

A new method for preparing black birnessite nanoparticles is introduced. The initial synthesis process resembles the classical McKenzie method of preparing brown birnessite except for slower cooling and closing the system from the ambient air. Subsequent process, including wet-aging at 7◦C for 48 hours, overnight freezing, and lyophilization, is shown to convert the brown birnessite into black birnessite with complex nanomorphology with folded sheets and spirals. Characterization of the product is performed by X-ray diffraction (XRD), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), thermogravimetric analysis (TGA), and N2 adsorption (BET) techniques. Wet-aging and lyophilization times are shown to …

Modeling And Design Algorithms For Electromagnetic Pumps, Daniel P. Cook, Yitung Chen, Jian Ma

Reactor Campaign (TRP)

Electromagnetic (EM) induction pumps are used extensively in current and proposed nuclear power systems and industrial molten metal transfer operations. Although the Magnetohydrodynamic (MHD) theory that underlies the operation of these types of pumps has been studied extensively in the past few decades, the design of specific EM pumping systems for specific flow cases requires computational tools and expertise, which is lacking in the U.S. However, for the past two years, researchers at UNLV have been utilizing the TC-1 liquid metal loop system at UNLV and an Annular Linear Induction Pump (ALIP) to drive the liquid metal and to develop …

Thermal Transient Flow Rate Sensor For High Temperature Liquid Metal Cooled Nuclear Reactor, Yingtao Jiang, Jian Ma

Reactor Campaign (TRP)

In nuclear power plants and accelerator driven systems (ADS) for nuclear waste treatment, it is important to monitor the coolant flow rate in the reactor core and pipe-line. In such a strong irradiation, high pressure, and temperature environment, the existing flow measurement techniques (such as Electromagnetic flow meters, Ultrasonic flow meters, Turbine flow meters, etc.) are not accurate and reliable.

The measurement of flow rates (mass flow rates or volume flow rate) plays a notable role in monitoring and controlling the experimental conditions. The bulk flow rates can be obtained through direct methods, which measure the amount of discharged fluids …

Knowledge-Based Information Resource Management System For Materials Of Sodium-Cooled Fast Reactor, Sean Hsieh

Reactor Campaign (TRP)

In the development of advanced fast reactors, materials and coolant/ material interactions pose a critical barrier for higher temperature and longer core life designs. For sodium-cooled fast reactors (SFRs) such as the Experimental Breeder Reactors in Idaho and the Fast Flux Test Facility in Hanford, experience has shown that qualified structural materials and fuel cladding severely limits their economic performance.

Liquid sodium has been selected as the primary coolant candidate for the Advanced Burner Reactor (ABR) of the Global Nuclear Partnership (GNEP). Materials improvement has been identified as a major thrust to improve fast reactor economics. Researchers from universities, national …

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

Mechanical Engineering Faculty Research

No abstract provided.

Carbon Permits, Jun-Ki Choi, Bhavik R. Bakshi

Mechanical and Aerospace Engineering Faculty Publications

The Encyclopedia of Global Warming and Climate Change helps readers learn about the astonishingly intricate processes that make ours the only planet known to be habitable. These three volumes include more than 750 articles that explore major topics related to global warming and climate change—ranging geographically from the North Pole to the South Pole, and thematically from social effects to scientific causes.

Tractor Test 1918: New Holland Tt 50a, 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 1938: New Holland T2330, New Holland Tc50, New Holland Boomer 3050, 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 1928: Challenger Mt945b Diesel, 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 …

Nebraska Summary: S645 Challenger Mt535b, 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 …

Nebraska Summary: S621a Case-Ih Magnum 180, 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 …

Nebraska Summary: S671 Case-Ih Puma 140, 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 …

Nebraska Summary: S656 Challenger Mt645c Scr, 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 …

Nebraska Summary: S726 New Holland T4050, 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 …

Nebraska Summary: S723 New Holland T4040, 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 …

Nebraska Summary: S719 New Holland T4020, 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 …

Fabrication Of High Aspect Ratio Metal Nanotips By Nanosecond Pulse Laser Melting, Bo Cui, Lin Wu, Stephen Y. Chou

Department of Mechanical and Materials Engineering: Faculty Publications

The authors have developed an approach to fabricate sharp and high aspect ratio metal tips using nanosecond pulse laser melting. A quartz wafer covered with a thin chromium (Cr) film was placed on top of a second wafer with a sub-micrometer gap between them and the Cr film facing the second wafer. Then an excimer laser pulse (308 nm wavelength, 20 ns pulse duration) was shone from the back of the quartz wafer and melted the Cr film momentarily (several hundred nanoseconds). It is found that the molten Cr films can self-form discrete metal pillars connecting the two wafers. After …

Control Of The Nanoscale Crystallinity And Phase Separation In Polymer Solar Cells, Chih-Wei Chu, Hoichang Yang, Wei-Jen Hou, Jinsong Huang, Gang Li, Yang Yang

Department of Mechanical and Materials Engineering: Faculty Publications

Grazing-incidence x-ray diffraction and atomic force microscopy were performed on bulk heterojunction regioregular poly(3-hexylthiophene) (RR-P3HT) [6,6]-phenyl-C₇₁-butyric acid methyl esters spin-cast films with different film processing conditions to correlate the crystalline nanostructure of P3HT with the corresponding solar cell performance. The increase in long wavelength absorption for solvent annealed films is related to highly conjugated crystal structure of RR-P3HT phase-separated in the active layer. Upon thermal annealing, the solvent annealed 50-nm-thick device shows high solar cell performance with fill factor up to 73% and power conversion efficiency of 3.80%.

Nebraska Tractor Test 1932: Agco Lt95a, 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 …

Reduced Order Modeling Of Time-Dependent Reflectance Profiles From Purely Scattering Media, R. Scott Larson, Matthew R. Jones

Faculty Publications

Due to the widespread existence and importance of foam, inverse techniques for characterizing industrial foams are of interest. An essential element in an inverse method used to characterize a foam layer is a model of the time-dependent reflectance of a laser pulse. Monte Carlo methods may be used to accurately model reflectance, but these methods are computationally expensive. Computationally efficient methods based on the diffusion approximation have been developed, but this approach is not sufficiently accurate in many cases of interest. Therefore, a computationally efficient and robust method is desirable. This paper presents a computationally efficient method for modeling the …

On Constitutive Models For Limited Elastic, Molecular Based Materials, Millard F. Beatty

Department of Engineering Mechanics: Faculty Publications

The response function for a general class of elastic molecular based materials characterized by their limiting molecular chain extensibility and depending on only the first principal invariant of the Cauchy–Green deformation tensor together with a certain molecular based limiting extensibility parameter is introduced. The constitutive response function for the Gent material is then derived inversely as the [0/1] Padé approximant of this class, a result that leads naturally to an infinite geometric series representation of its response function. Truncation of this series function characterizes a familiar class of quadratic materials now having physically relevant material constants. It is shown that …

Performance Comparison Of Pb(Zr0.52Ti0.48)O3-Only And Pb(Zr0.52Ti0.48)O3-On-Silicon Resonators, Hengky Chandrahalim, Sunil A. Bhave, Ronald G. Polcawich, Jeff Pulskamp, Dan Judy, Roger Kaul, Madan Dubey

Faculty Publications

This paper provides a quantitative comparison and explores the design space of lead zirconium titanate (PZT)–only and PZT-on-silicon length-extensional mode resonators for incorporation into radio frequency microelectromechanical system filters and oscillators. We experimentally measured the correlation of motional impedance (R_X) and quality factor (Q) with the resonators’ silicon layer thickness (t_Si). For identical lateral dimensions and PZT-layer thicknesses (t_PZT), the PZT-on-silicon resonator has higher resonant frequency (f_C), higher Q (5100 versus 140), lower R_X (51 Ω versus 205 Ω), and better linearity [third-order input intercept …

The Effect Of Stirring On The Morphology Of Birnessite Nanoparticles, Marcos A. Cheney, Pradip K. Bhowmik, Shingo Moriuchi, Mario Villabos, Shizhi Qian, Sang W. Joo

Mechanical & Aerospace Engineering Faculty Publications

The effect of mechanical stirring on the morphology of hexagonal layer- structure birnessite nanoparticles produced from decomposition of KMnO₄ in dilute aqueous H₂SO₄ is investigated, with characterization by X- ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high- resolution transmission electron microscopy (HRTEM), thermogravimetric analysis (TGA), and N₂ adsorption (BET). Mechanical stirring during an initial stage of synthesis is shown to produce black birnessite containing nanofibers, whereas granular particulates of brown birnessite are produced without stirring. This is the first reduction synthesis of black birnessite nanoparticles with dendritic morphology without any use …