Engineering Commons^™

Design And Use Of An Adjustable Clearance Flailing Knife Biomass Shredder To Mechanically Increase Particle Surface Area, Shawn Gregory Ehlers

Open Access Theses

A flailing knife shredder was designed and tested as an alternative to a hammermill for processing biomass. The machine was comprised of two cylinders with four rungs, each with five free-swinging blades. Each of the two cylinders had adjustable clearance hoods and variable speed drives. Energy usage, output characteristics and device capacities were compared with corn stover processed at moisture contents (MC) of 10%, 35% and 50% wet basis (WB). The hammermill produced a more uniform particle size distribution in comparison to the shredder. Accessibility, indicated by conductivity index, to plant constituents, revealed that the method of treatment was not-significant …

Control Of Impacting Dynamical Systems, Akhil Salunke

Open Access Theses

Impacting systems are encountered frequently in nature, and often in mechanical systems. Impacts can be undesirable in some applications, and desirable and deliberate in others. A subset of impacting systems are vibro&ndashimpact systems, wherein the impacts arise during vibrations or oscillatory behavior. Considering their potential prominence in a number of day&ndashto&ndashday applications, such vibro&ndashimpact systems have become the subject of extensive research in the past few decades. A significant number of these studies have been specifically aimed at controlling vibro&ndashimpact systems. To date, a wide variety of control algorithms have been proposed, a subset of which account for the effects …

Femtosecond Filament Interaction As A Probe For Molecular Alignment, Erik Mckee

Electronic Theses and Dissertations

Femtosecond laser filamentation is a highly nonlinear propagation mode. When a laser pulse propagates with a peak power exceeding a critical value Pcr (5 GW at 800 nm in air), the Kerr effect tends to collapse the beam until the intensity is high enough to ionize the medium, giving rise to plasma defocusing. A dynamic competition between these two effects takes place leaving a thin and weakly ionized plasma channel in the trail of the pulse. When an ultrafast laser pulse interacts with molecules, it will align them, spinning them about their axis of polarization. As the quantum rotational wave …

Preemptive Resume Priority Call Center Model With Two Classes Of Map Arrivals, Srinivas R. Chakravarthy, M. Senthil Kumar, R. Arumuganathan

Industrial & Manufacturing Engineering Publications

Generally in call centers, voice calls (say Type 1 calls) are given higher priority over e-mails (say Type 2 calls). An arriving Type 1 call has a preemptive priority over a Type 2 call in service, if any, and the preempted Type 2 call enters into a retrial buffer (of finite capacity). Any arriving call not able to get into service immediately will enter into the pool of repeated calls provided the buffer is not full; otherwise, the call is considered lost. The calls in the retrial pool are treated alike (like Type 1) and compete for service after a …

Layered Hepatocytes And Endothelial Cells On A Transwell Membrane: Toward Engineering The Liver Sinusoid, Young Bok (Abraham) Kang, Joseph Cirillo, Siddhartha Rawat, Michael Bouchard, Hongseok (Moses) Noh

Faculty Publications - Biomedical, Mechanical, and Civil Engineering

This paper presents a novel liver model that mimics the liver sinusoid where most liver activities occur. A key aspect of our current liver model is a layered co-culture of primary rat hepatocytes (PRHs) and primary rat liver sinusoidal endothelial cells (LSECs) or bovine aortic endothelial cells (BAECs) on a transwell membrane. When a layered co-culture was attempted with a thin Matrigel layer placed between hepatocytes and endothelial cells to mimic the space of Disse, the cells did not form completely separated monolayers. However, when hepatocytes and endothelial cells were cultured on the opposite sides of a transwell membrane, PRHs …

Robust Parafoil Terminal Guidance Using Massively Parallel Processing, Jonathan Rogers, Nathan Slegers

Faculty Publications - Biomedical, Mechanical, and Civil Engineering

Terminal guidance of autonomous parafoils is a difficult problem in which wind uncertainty and system underactuation are major challenges. Existing strategies almost exclusively use impact error as the criterion for optimality. Practical airdrop systems, however, must also include other criteria that maybe even more important than impact error for some missions, such as ground speed at impact or constraints imposed by drop zones with restrictions on flight patterns. Furthermore, existing guidance schemes determine terminal trajectories using deterministic wind information and may result in a solution that works in ideal wind but may be sensitive to variations. The work described here …

Projectile Fire-Control Algorithm In A Spatially Varying Wind Field, Lakmal Kaviratna, Mark Costello, Nathan Slegers

Faculty Publications - Biomedical, Mechanical, and Civil Engineering

The fire-control solution is an important element of any modern weapon system, providing precise aiming of the gun to enable highly accurate projectile impact. To be practical, the fire-control solution must be computed rapidly and reliably while simultaneously including all pertinent physical effects that can alter the trajectory and impact point. Current fire-control solutions account for the effect of atmospheric wind in a rudimentary manner, typically assuming a constant crosswind that is estimated in the field or measured at the firing site. With the advent of advanced wind-measurement systems (light detection and ranging, for example), it is now possible to …

Santa Clara Magazine, Volume 54 Number 3, Winter 2013, Santa Clara University

Santa Clara Magazine

16 - TO CATCH A THIEF by Vince Beiser. Mathematician George Mohler has helped equip police in Santa Cruz and L.A. with an algorithm that predicts where crimes might happen next. Is this the future of policing?

22 - HOW TO PREVENT A BONFIRE OF THE HUMANITIES by Michael S. Malone '75, MBA '77. A veteran chronicler of Silicon Valley looks at why the high-tech industry needs-and wants-folks who know how to tell a story.

26 - A POEM, A PRAYER, AND A MARTINI FOR THE RHINO Two conversations with Chancellor William J. Rewak, S.J.-who's just published his first collection …

Mobile Computing For Trauma And Surgical Care Continuous Education, Muhammad Y. Alamoud

Browse all Theses and Dissertations

In medical domain, mobile computing has proven to be convenient, effective, and productive. With varying screen sizes, there is a challenge to present the right information in the right format such that medical practitioners can access information quickly. In this thesis, we discuss how mobile computing can be used as a way of continuous education for medical practitioners in the field of trauma and surgical care, and provide design guidelines on how to effectively present information on different mobile form factors. The focus is on three screen sizes- 4.7, 7 and 10.1 in., and three interaction methods - dropdown, slide, …

Investigation Of Astm E 238 Bearing Pin Properties For Various Aerospace Alloys, Trevor J. Lee

Master's Theses

Aircraft are often designed with numbers determined by testing in a lab, rather than by repeatedly building prototypes. These lab tests conform to testing specifications so that the numbers can be compared between manufacturers, suppliers, and lab technicians. One such specification is ASTM specification E238 – 84(08), and it is used to determine important properties of a bearing pin joint like hinges, bolt holes, and rivet joints. The properties determined from this fastener-through-plate method are bearing strength, bearing yield strength, and bearing stiffness.

Adhering to the methods outlined in ASTM E238, a study was performed, looking at the effects that …

Conference Program, Cedric Briens, Jesús Arauzo, Dietrich Meier

Bioenergy III: Present and New Perspectives on Biorefineries

No abstract provided.

The Warehouse-Inventory-Transportation Problem For Multi-Echelon Supply Chains, Bhanuteja Sainathuni

Browse all Theses and Dissertations

Warehouses play a vital role in mitigating variations in supply and demand, and providing value-added services in a supply chain. However, our observation of supply chain practice reveals that warehousing decisions are not included when developing a distribution plan for the supply chain. This lack of integration has resulted in substantial variation in workload (42%-220%) at our industry partner's warehouse costing them millions of dollars. We address this real-world challenge by investigating the interdependencies between warehouse, inventory, and transportation decisions, integrate them in a mathematical programming model, and develop managerial insights based on solutions of industry-sized problem instances. Our three …

Calibration Of The Highway Safety Manual For Missouri, Carlos Sun Ph.D., P.E., Jd, Henry Brown Msce, P.E., Praveen Edara Ph.D., P.E., Boris Carlos, Kyuongmin Andrew Nam

Mid-America Transportation Center: Final Reports and Technical Briefs

The new Highway Safety Manual (HSM) contains predictive models that need to be calibrated to local conditions. This calibration process requires detailed data types, such as crash frequencies, traffic volumes, geometrics, and land-use. The HSM does not document in detail techniques for gathering such data, since data systems vary significantly across states. The calibration process also requires certain decisions, such as the correct sampling approach, determination of the minimum segment length, the treatment of left-turn phasing, and the inclusion or exclusion of speed-change lane crashes. This report describes the challenges, practical solutions, and results from a statewide HSM calibration in …

Examination Of Thermal Properties Of Carbon-Carbon And Graphitized Carbon-Carbon Composites, Melanie Jene' Patrick

Theses

Thermal characterization of composites is essential for their proper assignment to a specific application. Specific heat, thermal diffusivity, and thermal conductivity of carbon-carbon composites are essential in the engineering design process and in the analysis of aerospace vehicles, space systems and other high temperature thermal systems. Specifically, thermal conductivity determines the working temperature levels of a material and is influential in its performance in high temperature applications. There is insufficient thermal property data for carbon-carbon composites over a range of temperatures. The purpose of this research is to develop a thermal properties database for carbon-carbon composites that will contain in-plane …

Technology Adoption In Small And Medium-Sized Logistics Providers, Pietro Evangelista, Alan Mckinnon, Edward Sweeney

Articles

Purpose - The main aim of the research is to shed light on the role of information and communication technology (ICT) in the logistics innovation process of small and medium- sized third party logistics providers (3PLs).

Design/methodology/approach – A triangulated research strategy was designed using a combination of quantitative and qualitative methods. The former involved the use of a questionnaire survey of small and medium-sized Italian 3PLs with 153 usable responses received. The latter comprised a series of focus groups and the use of seven case studies.

Findings – There is a relatively low level of ICT expenditure with few …

Comparison Of Post-Detonation Combustion In Explosives Incorporating Aluminum Nanoparticles: Influence Of The Passivation Layer, William K. Lewis, C. G. Rumchik, M. J. Smith, K. A. Shiral Fernando, Christopher A. Crouse, Jonathan E. Spowart, Elena A. Guliants, Christopher E. Bunker

Electrical and Computer Engineering Faculty Publications

Aluminum nanoparticles and explosive formulations that incorporate them have been a subject of ongoing interest due to the potential of aluminum particles to dramatically increase energy content relative to conventional organic explosives. We have used time-resolved atomic and molecular emission spectroscopy to monitor the combustion of aluminum nanoparticles within the overall chemical dynamicsof post-detonation fireballs. We have studied the energy release dynamics of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) charges incorporating three types of aluminum nanoparticles: commercial oxide-passivated nanoparticles, oleic acid-capped aluminum nanoparticles (AlOA), and nanoparticles in which the oxide shell of the particle has been functionalized with an acrylic monomer and copolymerized into …

A Decision Support System For The Intelligence Satellite Analyst, Gi Yeon Park

Dissertations

The study developed a decision support system known as Visual Analytic Cognitive Model (VACOM) to support the Intelligence Analyst (IA) in satellite information processing task within a Geospatial Intelligence (GEOINT) domain. As a visual analytics, VACOM contains the image processing algorithms, a cognitive network of the IA mental model, and a Bayesian belief model for satellite information processing. A cognitive analysis tool helps to identify eight knowledge levels in a satellite information processing. These are, spatial, prototypical, contextual, temporal, semantic, pragmatic, intentional, and inferential knowledge levels, respectively. A cognitive network was developed for each knowledge level with data input from …

Gis And Introductory Environmental Engineering: A Way To Fold Gis Into An Already-Existing Course, Mary P. Cardenas, David Wayne Kelley, Warren Roberts

All HMC Faculty Publications and Research

The use of Geographical Information Systems (GIS) was implemented in the upper-division undergraduate technical elective Introduction to Environmental Engineering at Harvey Mudd College. Students integrated technical engineering skills, newly-learned geographical information system (GIS) skills, and the engineering design process, all in the context of the design of a debris flow barrier for a wilderness land parcel acquired by a local conservancy group.

Junior and senior general engineering students, the majority of whom had no experience with GIS, were taught ArcGIS (a GIS mapping program) in the context of an Introductory Environmental Engineering course. Students learned how to map locations, find …

The Decline Of The Car Enthusiasts: Implications For Undergraduate Engineering Education, Mary P. Cardenas

All HMC Faculty Publications and Research

Hands-on, project-based engineering education is alive and well. However, anecdotal evidence indicates that we are seeing fewer undergraduate engineering students who arrive on campus already knowing how to ‘use their hands’—having familiarity with tools and mechanical devices, knowing how to connect things, savvy about avoiding leaks in fluid systems, wary of stripping a screw thread or shearing a bolt head—the kinds of things that an archetypal car enthusiast would have learned in high school. For design-build-test project-based engineering educational experiences, having at least one car enthusiast has proven invaluable: more time can be spent on testing and re-designing, rather than …

Me-Em 2012-13 Annual Report, Department Of Mechanical Engineering-Engineering Mechanics, Michigan Technological University

Department of Mechanical and Aerospace Engineering Annual Reports

Table of Contents

• Research Centers
• Students
• Faculty & Staff
• Alumni
• Contracts & Grants
• Publications

Reducing Uncertainty In Fatigue Life Limits Of Turbine Engine Alloys, J M. Larson, S K. Jha, C J. Szczepanski, M J. Caton, R John, A H. Rosenberger, D J. Buchanan, P J. Golden, J R. Jira

United States Air Force: Publications

In probabilistic design of materials for fracture-critical components in modern military turbine engines, a typical maximum design target risk (DTR) is 5 X 10^-8 component failures/engine flight hour. This metric underscores the essential role of safety in a design process that simultaneously strives to achieve performance, efficiency, reliability, and affordability throughout the life cycle of the engine. Traditionally, the design and life management approaches for engine materials have typically relied on extensive testing programs to produce large databases of fatigue data, from which statistically based life limits are derived by extrapolation from the mean fatigue behavior. However, we …

Stability And Power Optimality In Time-Periodic Flapping Wing Structures, Bret Stanford, Philip Beran, Richard Snyder, Mayuresh Patil

United States Air Force: Publications

This paper investigates the nonlinear dynamics of a vehicle with two flexible flapping wings. The body dynamics and the wings' deformation are monolithically grouped into a single system of equations, with aerodynamics accounted for by a quasi-steady blade element method. A periodic shooting method is then used to locate closed orbits of this non-autonomous system, and Floquet multipliers assess the linearized stability about the nonlinear orbit. This framework is then exposed to a gradient based optimizer, in order to quantify the role of wing planform variables, wing structure variables, and kinematic actuation variables in obtaining vehicles with superior open-loop stability …

Special Issue On Medical Simulation, Michel Audette, Hanif M. Ladak

Computational Modeling & Simulation Engineering Faculty Publications

We would like to welcome you to this Special Issue on Medical Simulation, the first of its kind not only for SIMULATION: Transactions of The Society for Modeling and Simulation International, but for any technical journal. Our respective backgrounds are an indication of the technical and clinical breadth of medical simulation, as we approach the subject as primarily medical image analysis and biomechanics experts respectively, each with a variety of clinical interests spanning virtual reality (VR)–based neuro-, orthopedic and ear-nose-and-throat surgery. Moreover, we believe that the breadth of the papers that comprise this issue reflects an even broader perspective. After …

An Empirical Muscle Intracellular Action Potential Model With Multiple Erlang Probability Density Functions Based On A Modified Newton Method, Gyutae Kim, Mohammed M. Ferdjallah, Frederic D. Mckenzie

Computational Modeling & Simulation Engineering Faculty Publications

The convolution of the transmembrane current of an excitable cell and a weighting function generates a single fiber action potential (SFAP) model by using the volume conductor theory. Here, we propose an empirical muscle IAP model with multiple Erlang probability density functions (PDFs) based on a modified Newton method. In addition, we generate SFAPs based on our IAP model and referent sources, and use the peak-to-peak ratios (PPRs) of SFAPs for model verification. Through this verification, we find that the relation between an IAP profile and the PPR of its SFAP is consistent with some previous studies, and our IAP …

Liver On A Chip; Engineering The Liver Sinusoid, Young Bok (Abraham) Kang

Faculty Publications - Biomedical, Mechanical, and Civil Engineering

We have developed a novel microfluidic device using poly-dimethylsiloxane (PDMS) microchannels for long term, layered co-culture of primary rat hepatocytes (PRH) and endothelial cells (EC) to mimic the liver sinusoid. Three microfluidic configurations were investigated as shown in Figure 1. In configuration 1, where PRH and rat adrenal medullary endothelial cells (RAMEC) were cocultured with matrigel in layers in a single PDMS microchannel, cells remained viable for 30 days. In configuration 3, where PRH and liver sinusoidal endothelial cells (LSEC) were cultured on the opposite sides of the microporous membrane between two microchannels under static and dynamic conditions, PRH retained …

Applying Mobile Application Development To Help Dementia And Alzheimer Patients, Jean F. Coppola Phd, Marc A. Kowtko, Christina Yamagata, Shannon Joyce

Wilson Center for Social Entrepreneurship

Caregiver anecdotes attest that music and photographs play an important role for family members diagnosed with Alzheimer’s disease (AD), even those with severe AD. Tablets and iPads, which are prevalent, can be utilized with dementia patients in portraying favorite music and family photographs via apps developed in close partnership with geriatric facilities. This study addresses cognitive functioning and quality of life for people diagnosed with dementia via technology. Research has shown that technology instruments such as iPods, help stimulate those with dementia. This study focuses on innovative devices such as iPads and tablets, which are mainstream and easy to use, …

Maintaining The Master International Frequency Register, Frans G. Von Der Dunk

Space, Cyber, and Telecommunications Law Program: Faculty Publications

The present paper is the written elaboration of a presentation held under the same title at the workshop “International Regulations of Space Communications” held in Luxembourg on 24 and 25 May 2012. Consequently, the topic of this paper, the maintenance of the Master International Frequency Register as a key tool for allowing satellite communications to be a viable international sector of space activities, is viewed through the looking glass of the session title, “WRC-12 from the Perspective of International Telecommunications Law.”

In other words, it does not purport to deal with the actual details of maintaining the Register …

Thermal Characterization Of As4/3501-6 Carbon-Epoxy Composite, Bradley R. Doleman

Theses

Thermal diffusivity, specific heat, and thermal conductivity are important thermophysical properties of composite materials and foams. Thermal characterization provides these material properties which play a significant role in the engineering design process of space systems, aerospace vehicles, transportation, energy storage devices, and power generation including fuel cells. Thermal conductivity is the parameter that is important in problems involving heat transfer and thermal structures. Because it determines the working temperature levels of a material, the thermal conductivity is critical when considering the performance of materials in high temperature applications as well as safety, process control, and quality assurance. As a result …

Transient And Quasi-Steady Thermal Behaviour Of A Building Envelope Due To Retrofitted Cavity Wall And Ceiling Insulation, Aimee Byrne, Gerard Byrne, Anna Davies, Anthony Robinson

Articles

Accurate understanding of the thermal behaviour of building components is essential for predicting heat-ing or cooling needs and facilitates the implementation of more successful energy saving strategies and retrofits. This paper focuses on a specific measure commonly introduced through the residential energy efficiency retrofit programmes in Ireland–insulation. Traditionally, assessments of the performance of building envelopes have been based on assumed thermal resistances of the materials involved, labora-tory tests and computer modelling. The aim of the present work is to investigate the in situ thermal behaviour of a case study building and its components under transient and quasi-steady environmental conditions, comparing …

Test 2064: Kubota M135gx, 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 …