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Articles 1 - 15 of 15

Full-Text Articles in Mechanical Engineering

High-Level, Product Type-Specific Programmatic Operations For Streamlining Associative Computer-Aided Design, Nathan W. Scott Aug 2008

High-Level, Product Type-Specific Programmatic Operations For Streamlining Associative Computer-Aided Design, Nathan W. Scott

Theses and Dissertations

Research in the field of Computer Aided Design (CAD) has long focused on reducing the time and effort required of engineers to define three dimensional digital product models. Parametric, feature-based modeling with inter-part associativity allows complex assembly designs to be defined and re-defined while maintaining the vital part-to-part interface relationships. The top-down modeling method which uses assembly level control structures to drive child level geometry has proved valuable in maintaining these interfaces. Creating robust parametric models like these, however, is very time consuming especially since there can be hundreds of features and thousands of mathematical expressions to create. Even if ...


Mechanical Engineering Education In Irish Context: On Route To Becoming A Chartered Engineer, David Kennedy, Richard Good Jan 2008

Mechanical Engineering Education In Irish Context: On Route To Becoming A Chartered Engineer, David Kennedy, Richard Good

Conference Papers

Engineering Education in Ireland and throughout Europe has changed dramatically over the last few years and the pace of change is ensuring that we, the educators are constantly keeping abreast of new developments and benchmarks. Programmes that were based on inputs from learners are now outcomes based and the onus is on the educators and facilitators to provide evidence that graduates are capable of conducting specific tasks, commonly termed as Programme Outcomes. Similarly, greater onus is now placed on the learner to take greater responsibility for their educational development. The new and current process of meeting the educational requirements of ...


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 ...


Establishing An Advanced Engineering Framework For Engineering Decision Making, Douglas Stinson Mccorkle Jan 2008

Establishing An Advanced Engineering Framework For Engineering Decision Making, Douglas Stinson Mccorkle

Retrospective Theses and Dissertations

No abstract provided.


Energy Comparison Of Under Floor Air Distribution Heating Ventilation And Air Conditioning Systems In Office Buildings, Jonathon Richard Giles Jan 2008

Energy Comparison Of Under Floor Air Distribution Heating Ventilation And Air Conditioning Systems In Office Buildings, Jonathon Richard Giles

Retrospective Theses and Dissertations

The purpose of this paper is to compare energy consumption with under floor air distribution systems for office buildings, specifically a call center application.;The building being modeled will have an HVAC system that utilizes an underfloor air distribution system (UFAD). This type of system allows air to be introduced into the plenum space under the floor. The air comes up through the floor into the space through plenum space pressurization. The air is then taken out of the space up high and returned back to the air handling unit.;The three systems reviewed for delivery of the air to ...


Investigation Into The Stress Assisted Damage Of Copper Surface Under Single Asperity: Influence Of Contact Pressures, Surfaces Stress States And Environments, Bun Hiong Chua Jan 2008

Investigation Into The Stress Assisted Damage Of Copper Surface Under Single Asperity: Influence Of Contact Pressures, Surfaces Stress States And Environments, Bun Hiong Chua

Retrospective Theses and Dissertations

An experiment setup was used to investigate the effects of contact loads, surface stress state and surface environment on dissolution and damage of copper surface. A range of surface stress state was generated with a four-point-bending setup on a well-polished copper sample. Single asperity contact was investigated using the cantilever tip of an Atomic Force Microscope. Controlled tip contact pressures were applied on the copper surface to mechanically stimulate the stressed surface. The experiment was performed in different environments to determine the chemical effects. Volume of material removed during the process was measured to determine material removal rate as a ...


Simulating Energy Efficiency In Laboratory Buildings, Robert Marcel Milbrandt Jan 2008

Simulating Energy Efficiency In Laboratory Buildings, Robert Marcel Milbrandt

Retrospective Theses and Dissertations

Today's laboratory buildings are large consumers of energy. The ventilation requirements of these buildings mandate that large quantities of outside air be brought into the building. The advent of air-to-air heat recovery systems has been proven to significantly decrease the energy input needed to condition outside air. This project is a detailed energy simulation of a laboratory building on the campus of Iowa State University in Ames, Iowa. Using Trane TRACE 700 software, a detailed model of the building was created, and energy efficient measures were simulated. These simulations include the proper control of outside air flow rates, the ...


Modeling And Simulation Of Nanoparticle Aggregation In Colloidal Systems, Sergiy Markutsya Jan 2008

Modeling And Simulation Of Nanoparticle Aggregation In Colloidal Systems, Sergiy Markutsya

Retrospective Theses and Dissertations

Prediction of colloidal nanoparticle aggregation is an important problem which needs to be solved in an accurate and efficient manner. Thus, accurate modeling of physico-chemical interactions is required. In addition, to have good aggregation statistics, large system sizes should be considered, which can significantly increase computational cost and decrease code efficiency. In ideal case model which is chosen to predict colloidal nanoparticle aggregation should accurately describe physico-chemical interactions of relatively large physical systems, and at the same time, simulate at low computational cost.;In this research, two simulation approaches, molecular dynamics (MD) and Brownian dynamics (BD), are analyzed and compared ...


Analysis Of A Ddgs Air-Drying System With Heat Recovery, Christopher Brady Hoeck Jan 2008

Analysis Of A Ddgs Air-Drying System With Heat Recovery, Christopher Brady Hoeck

Retrospective Theses and Dissertations

Dry Distiller Grains with Soluble (DDGS) are a co-product of the conversion from corn into Ethanol fuel. Several applications depend on the ability of a drying process to remove moisture from a product, such as DDGS, in an effective and economical manner. Common drying methods use air to facilitate product drying as it proficiently absorbs the unwanted moisture, creating a moist-air mixture that captures both the latent and sensible heat released from the product. The most economical approach to an Air Drying System integrates a heat recovery system that transfers the heat removed by the moist-air mixture during drying back ...


Devising A More Robust Automated Detection Method Using Audio Frequency Spectra, Gregory Stargell Jan 2008

Devising A More Robust Automated Detection Method Using Audio Frequency Spectra, Gregory Stargell

Retrospective Theses and Dissertations

The space shuttle, Columbia had a suitcase piece of the SOFI strike the wing of the shuttle causing its demise. Detection methods were evaluated to detect defects in the foam. One of the methods being free field acoustics was explored. Previous works were done in this area, and it showed promise as it was able to detect defects. However all defects or the defects that had significance to the eye was not detected. The method developed before is looked into and was improved upon addressing the problems. Developing a baseline curve and region to compare the data would be two ...


Visualizing Fluidized Beds With X-Rays, Nathan Paul Franka Jan 2008

Visualizing Fluidized Beds With X-Rays, Nathan Paul Franka

Retrospective Theses and Dissertations

This study applies minimum fluidization velocity experiments, X-ray computed tomography (CT), X-ray stereography, and particle tracking to fluidized beds of glass beads, ground walnut shell, and ground corncob operating with a variety of flow conditions. 3-D local, time-averaged gas holdup is calculated from CT data, while dynamic features are captured by X-ray stereography. The results show that CT is most effective on glass bead fluidized beds. Due to high X-ray attenuation, glass bead CT data has higher resolution than walnut shell and corncob beds. Glass bead gas holdup data also feature the lowest noise due to the high homogeneity of ...


Characterization Of Actuator Behaviors Of Ferrogels Obtained From Physical And Chemical Cross-Linking Methods, Geunhyung Park Jan 2008

Characterization Of Actuator Behaviors Of Ferrogels Obtained From Physical And Chemical Cross-Linking Methods, Geunhyung Park

Retrospective Theses and Dissertations

Ferrogels are soft polymer materials containing a filler of magnetic particles that allow the material to be activated by magnetic fields. These materials have shown capabilities for large strains, fast response, ease of synthesis and biocompatibility and have potential applications including artificial muscles, controlled drug release systems, and hyperthermia cancer treatment. In this work, the actuator behavior for a selection of ferrogel compositions and synthesis methods are characterized including their free strain and loading behavior. Samples were synthesized using either chemical or physical methods using Sodium Tetra-borate (Na2B4O7 ยท 10(H2O)) or freeze-thaw cycle, respectively. Compositions consisting of PVA of 4 ...


An Energy And Cost Analysis Of Residential Ground-Source Heat Pumps In Iowa, Matthew James Swenka Jan 2008

An Energy And Cost Analysis Of Residential Ground-Source Heat Pumps In Iowa, Matthew James Swenka

Retrospective Theses and Dissertations

The objective of this study was to evaluate residential ground-source heat pumps throughout the state of Iowa and use that information to develop educational opportunities for prospective ground-source heat pump owners. The ground-source heat pumps were evaluated based on performance, efficiency, and economics. The study was limited to similar homes throughout the state of Iowa, recent constructions (1997 to 2001), and vertically or horizontally configured loops.;Energy audits were conducted for each home to obtain building characteristics. Using the characteristics, heating and cooling loads were estimated for each home. Utilizing the heating and cooling loads along with utility bill and ...


Force Interaction Characterization Between Thrombin And Dna Aptamers, Janice Dionne Marquardt Jan 2008

Force Interaction Characterization Between Thrombin And Dna Aptamers, Janice Dionne Marquardt

Retrospective Theses and Dissertations

The first purpose of this study is to examine using AFM height measurements to detect changes in nucleic acid and protein interactions. This study used a thiolated adenine oligonucleotide (Poly A) and thymine DNA strand (Poly T) or 2 kDa poly(ethylene) glycol (PEG) as control, and the thrombin aptamer and thrombin for detection pair. The poly A and aptamer were printed using microcontact printing, then exposed to complementary species. There was a height change after binding to the target species, so it is feasible for height data to detect binding. The second purpose of this study is to use ...


The Role Of Information Flow In Engineering Optimization, Steven Michael Corns Jan 2008

The Role Of Information Flow In Engineering Optimization, Steven Michael Corns

Retrospective Theses and Dissertations

Current optimization techniques work well for single components represented by a single model. However, many of the problems we face today are multi-disciplinary problems requiring the integration of complex models from different fields to gain a more complete understanding of the overall performance of a biological, engineering, or human system. One example is a modern automobile. Multiple systems (such as the power train and electronic engine control system) are designed and built from various assemblies and components, all of which are then integrated into one final product. This design process evokes a systems-of-systems concept that is also found in agricultural ...