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Superfast Phase-Shifting Method For 3-D Shape Measurement, Song Zhang, Daniel Van Der Welde, James H. Oliver 2010 Iowa State University

Superfast Phase-Shifting Method For 3-D Shape Measurement, Song Zhang, Daniel Van Der Welde, James H. Oliver

Mechanical Engineering Publications

Recently introduced DLP Discovery technology allows for tens of kHz binary image switching, which has great potential for superfast 3-D shape measurement. This paper presents a system that realizes 3-D shape measurement by using a DLP Discovery technology to switch binary structured patterns at very high frame rates. The sinusoidal fringe patterns are generated by properly defocusing the projector. Combining this approach with a phase-shifting method, we achieve an unprecedented rate for 3-D shape measurement: 667 Hz. This technology can be applied to numerous applications including medical science, biometrics, and entertainment.


An Alternative Method To Determining Optical Lever Sensitivity In Atomic Force Microscopy Without Tip-Sample Contact, Christopher J. Tourek, Sriram Sundararajan 2010 Iowa State University

An Alternative Method To Determining Optical Lever Sensitivity In Atomic Force Microscopy Without Tip-Sample Contact, Christopher J. Tourek, Sriram Sundararajan

Mechanical Engineering Publications

Force studies using atomic force microscopy generally require knowledge of the cantilever spring constants and the optical lever sensitivity. The traditional method of evaluating the optical lever sensitivity by pressing the tip against a hard surface can damage the tip, especially sharp ones. Here a method is shown to calculate the sensitivity without having to bring the tip into contact. Instead a sharpened tungsten wire is used to cause a point contact directly onto the cantilever and cause cantilever bending. Using beam theory, the sensitivity thus found can be converted to the equivalent sensitivity that would be obtained using the ...


Virtual Reality For Assembly Methods Prototyping: A Review, Abbishek Seth, Judy M. Vance, James H. Oliver 2010 Caterpillar, Inc.

Virtual Reality For Assembly Methods Prototyping: A Review, Abbishek Seth, Judy M. Vance, James H. Oliver

Mechanical Engineering Publications

Assembly planning and evaluation is an important component of the product design process in which details about how parts of a new product will be put together are formalized. A well designed assembly process should take into account various factors such as optimum assembly time and sequence, tooling and fixture requirements, ergonomics, operator safety, and accessibility, among others. Existing computer-based tools to support virtual assembly either concentrate solely on representation of the geometry of parts and fixtures and evaluation of clearances and tolerances or use simulated human mannequins to approximate human interaction in the assembly process. Virtual reality technology has ...


Characterization Of Biochars Produced From Cornstovers For Soil Amendment, James W. Leeq, MIchelle Kidder, Barbara R. Evans, Sokwon Paik, A.C. Buchanan III, Charles T. Garten, Robert C. Brown 2010 Oak Ridge National Laboratory

Characterization Of Biochars Produced From Cornstovers For Soil Amendment, James W. Leeq, Michelle Kidder, Barbara R. Evans, Sokwon Paik, A.C. Buchanan Iii, Charles T. Garten, Robert C. Brown

Mechanical Engineering Publications

Through cation exchange capacity assay, nitrogen adsorption−desorption surface area measurements, scanning electron microscopic imaging, infrared spectra and elemental analyses, we characterized biochar materials produced from cornstover under two different pyrolysis conditions, fast pyrolysis at 450 °C and gasification at 700 °C. Our experimental results showed that the cation exchange capacity (CEC) of the fast-pyrolytic char is about twice as high as that of the gasification char as well as that of a standard soil sample. The CEC values correlate well with the increase in the ratios of the oxygen atoms to the carbon atoms (O:C ratios) in the ...


Preliminary Investigation On Determining The Minimum Cement Content In Rigid Pavements, Ezgi Yurdakul, Peter Taylor, Halil Ceylan, Fatih Bektas 2010 Iowa State University

Preliminary Investigation On Determining The Minimum Cement Content In Rigid Pavements, Ezgi Yurdakul, Peter Taylor, Halil Ceylan, Fatih Bektas

Civil, Construction and Environmental Engineering Conference Presentations and Proceedings

This paper presents the preliminary results of an experimental program that consists of testing of concrete mixtures with varying water-to-binder ratios (w/b) and cementitious contents. The purpose of this laboratory study is to investigate the minimum cement content that can be used in rigid pavements without sacrificing the performance (i.e., strength and durability). Initially, 16 mixes using only portland cement and 48 mixes incorporating supplementary cementitious materials, namely class F fly ash, class C fly ash and slag as portland cement replacement at levels of 20%, 20% and 40%, respectively, were planned. This paper reports the results of ...


Application Of Shuffled Complex Evolution Optimization Approach To Concrete Pavement Backanalysis, Kasthurirangan Gopalakrishnan, Halil Ceylan 2010 Iowa State University

Application Of Shuffled Complex Evolution Optimization Approach To Concrete Pavement Backanalysis, Kasthurirangan Gopalakrishnan, Halil Ceylan

Civil, Construction and Environmental Engineering Conference Presentations and Proceedings

This paper focuses on the development of a new backcalculation method for concrete pavements based on a hybrid evolutionary global optimization algorithm, namely Shuffled Complex Evolution (SCE). Evolutionary optimization algorithms are ideally suited for intrinsically multi-modal, non-convex, and discontinuous real-world problems such as pavement backcalculation because of their ability to explore very large and complex search spaces and locate the globally optimal solution using a parallel search mechanism as opposed to a point-by-point search mechanism employed by traditional optimization algorithms. Shuffled Complex Evolution (SCE), a type of evolutionary optimization algorithms based on the tradeoff of exploration and exploitation, has been ...


Natural Selection Of Asphalt Mix Stiffness Predictive Models With Genetic Programming, Kasthurirangan Gopalakrishnan, Sunghwan Kim, Halil Ceylan, Siddhartha K. Khaitan 2010 Iowa State University

Natural Selection Of Asphalt Mix Stiffness Predictive Models With Genetic Programming, Kasthurirangan Gopalakrishnan, Sunghwan Kim, Halil Ceylan, Siddhartha K. Khaitan

Civil, Construction and Environmental Engineering Conference Presentations and Proceedings

Genetic Programming (GP) is a systematic, domain-independent evolutionary computation technique that stochastically evolves populations of computer programs to perform a user-defined task. Similar to Genetic Algorithms (GA) which evolves a population of individuals to better ones, GP iteratively transforms a population of computer programs into a new generation of programs by applying biologically inspired operations such as crossover, mutation, etc. In this paper, a population of Hot-Mix Asphalt (HMA) dynamic modulus stiffness prediction models is genetically evolved to better ones by applying the principles of genetic programming. The HMA dynamic modulus (|E*|), one of the stiffness measures, is the primary ...


Cytocompatible Cross-Linking Of Electrospun Zein Fibers For The Development Of Water-Stable Tissue Engineering Scaffolds, Quiran Jiang, Narendra Reddy, Yiqi Yang 2010 University of Nebraska–Lincoln

Cytocompatible Cross-Linking Of Electrospun Zein Fibers For The Development Of Water-Stable Tissue Engineering Scaffolds, Quiran Jiang, Narendra Reddy, Yiqi Yang

Biological Systems Engineering: Papers and Publications

This paper reports a new method of cross-linking electrospun zein fibers using citric acid as a non-toxic cross-linker to enhance the water stability and cytocompatibility of zein fibers for tissue engineering and other medical applications. The electrospun structure has many advantages over other types of structures and protein-based biomaterials possess unique properties preferred for tissue engineering and other medical applications. However, ultrafine fiber matrices developed from proteins have poor mechanical properties and morphological stability in the aqueous environments required for medical applications. Efforts have been made to improve the water stability of electrospun protein scaffolds using cross-linking and other approaches ...


Extrusion Systems: Components, Qi Fang, Milford Hanna 2010 Banner Pharmacaps, Inc., High Point, North Carolina

Extrusion Systems: Components, Qi Fang, Milford Hanna

Biological Systems Engineering: Papers and Publications

An extrusion system can be very simple to very complex. The complexity, or versatility, of a particular system is determined by the range of feedstocks to be processed, the desired transformations of the feedstocks, and the desired form of the products resulting from the process. These determine the specific design requirements of the various components of an extrusion system.


Nebraska Agricultural Water Management Demonstration Network (Nawmdn): Integrating Research And Extension/Outreach, Suat Irmak, Jennifer M. Rees, Gary L. Zoubek, Brandy S. van DeWalle, William R. Rathje, Rodney DeBuhr, Dan Leininger, Darrel D. Siekman, James W. Schneider, Andrew P. Christiansen 2010 University of Nebraska-Lincoln

Nebraska Agricultural Water Management Demonstration Network (Nawmdn): Integrating Research And Extension/Outreach, Suat Irmak, Jennifer M. Rees, Gary L. Zoubek, Brandy S. Van Dewalle, William R. Rathje, Rodney Debuhr, Dan Leininger, Darrel D. Siekman, James W. Schneider, Andrew P. Christiansen

Biological Systems Engineering: Papers and Publications

Maximizing the net benefits of irrigated plant production through appropriately designed agricultural water management programs is of growing importance in Nebraska, and other western and Midwestern states, because many areas are involved in management and policy changes to conserve irrigation water. In Nebraska, farmers are being challenged to practice conservation methods and use water resources more efficiently while meeting plant water requirements and maintaining high yields. Another challenge Nebraska experiences in it's approximately 3.5‐million‐ha irrigated lands is limited adoption of newer technologies/tools to help farmers better manage irrigation, conserve water and energy, and increase plant ...


Testing Fuel Efficiency Of A Tractor With A Continuously Variable Transmission, Bart A. Coffman, Michael F. Kocher, Viacheslav I. Adamchuk, Roger M. Hoy, Erin E. Blankenship 2010 University of Nebraska-Lincoln

Testing Fuel Efficiency Of A Tractor With A Continuously Variable Transmission, Bart A. Coffman, Michael F. Kocher, Viacheslav I. Adamchuk, Roger M. Hoy, Erin E. Blankenship

Biological Systems Engineering: Papers and Publications

A John Deere 8530 IVT tractor (Waterloo, Iowa) with a continuously variable transmission (CVT) that could be operated in automatic (CVT) or manual (fixed gear ratio) mode was tested for fuel consumption at a setpoint travel speed of 9 km·h‐1 with 17 different drawbar loads. Linear regression analysis results showed that with the throttle set to maximum in both transmission modes, operating the tractor with the transmission in the automatic mode was more fuel efficient than operating with the transmission in the manual mode when the drawbar power was approximately 78%, or less, of maximum power. When load ...


The Challenges Of Wastewater Irrigation In Developing Countries, M. Qadir, D. Wichelns, L. Raschid-Sally, Peter G. McCornick, P. Drechsel, A. Bahri, P. S. Minhas 2010 International Center for Agricultural Research in the Dry Areas

The Challenges Of Wastewater Irrigation In Developing Countries, M. Qadir, D. Wichelns, L. Raschid-Sally, Peter G. Mccornick, P. Drechsel, A. Bahri, P. S. Minhas

Daugherty Water for Food Global Institute: Faculty Publications

The volume of wastewater generated by domestic, industrial, and commercial sources has increased with population, urbanization, improved living conditions, and economic development. The productive use of wastewater has also increased, as millions of small-scale farmers in urban and peri-urban areas of developing countries depend on wastewater or wastewater-polluted water sources to irrigate high-value edible crops for urban markets, often as they have no alternative sources of irrigation water. Undesirable constituents in wastewater can harm human health and the environment. Hence, wastewater irrigation is an issue of concern to public agencies responsible for maintaining public health and environmental quality. For diverse ...


Challenges And Prospects Of Sustainable Groundwater Management In The Indus Basin, Pakistan, Asad Sarwar Qureshi, Peter G. McCornick, A. Sarwar, Bharat R. Sharma 2010 International Water Management Institute

Challenges And Prospects Of Sustainable Groundwater Management In The Indus Basin, Pakistan, Asad Sarwar Qureshi, Peter G. Mccornick, A. Sarwar, Bharat R. Sharma

Daugherty Water for Food Global Institute: Faculty Publications

In Pakistan, on-demand availability of groundwater has transformed the concept of low and uncertain crop yields into more assured crop production. Increased crop yields have resulted in food security and improved rural livelihoods. However, this growth has also led to problems of overdraft, falling water tables, and degradation of groundwater quality, and yields generally remain well below potential levels. Over the last three decades, Pakistan has tried several direct and indirect management strategies for groundwater management. However the success has been limited. This paper argues that techno-institutional approaches such as introducing water rights, direct or indirect pricing, and permit systems ...


Thermal Analog To Afm Force-Displacement Measurements For Nanoscale Interfacial Contact Resistance, Brian D. Iverson, John E. Blendell, Suresh V. Garimella 2010 Brigham Young University - Provo

Thermal Analog To Afm Force-Displacement Measurements For Nanoscale Interfacial Contact Resistance, Brian D. Iverson, John E. Blendell, Suresh V. Garimella

Faculty Publications

Thermal diffusion measurements on PMMA-coated Si substrates using heated AFM tips were performed to determine the contact resistance between an organic thin film and Si. The measurement methodology presented demonstrates how the thermal contrast signal obtained during a force-displacement ramp is used to quantify the resistance to heat transfer through an internal interface. The results also delineate the interrogation thickness beyond which thermal diffusion in the organic thin film is not affected appreciably by the underlying substrate.


Unconventional Uses Of Cantilevers For Chemical Sensing In Gas And Liquid Environments, Isabelle Dufour, Fabien Josse, Stephen M. Heinrich, C. Lucat, C. Ayela, F. Ménil, Oliver Brand 2010 Université de Bordeaux

Unconventional Uses Of Cantilevers For Chemical Sensing In Gas And Liquid Environments, Isabelle Dufour, Fabien Josse, Stephen M. Heinrich, C. Lucat, C. Ayela, F. Ménil, Oliver Brand

Civil and Environmental Engineering Faculty Research and Publications

Microcantilevers used as (bio)chemical sensors are usually coated with a chemically sensitive layer. The coated devices operate either in a static bending regime or in a dynamic flexural mode. While the coated devices operate generally well in both the static and dynamic mode, they do suffer from certain shortcomings depending on the medium of operation and the application, including lack of selectivity and of reversibility of the sensitive coating and a reduced quality factor due to the surrounding medium. In particular, the performance of microcantilevers excited in their standard out-of-plane dynamic mode drastically decreases in viscous liquid media. Moreover ...


Tapping Environmental History To Recreate America’S Colonial Hydrology, Christopher L. Pastore, Mark B. Green, Daniel J. Bain, Andrea Muñoz-Hernandez, Charles J. Vörösmarty, Jennifer Arrigo, Sara Brandt, Jonathan M. Duncan, Francesca Greco, Hyojin Kim, Sanjiv Kumar, Michael Lally, Anthony J. Parolari, Brian Pellerin, Nira Salant, Adam Schlosser, Kate Zalzal 2010 University of New Hampshire, Durham

Tapping Environmental History To Recreate America’S Colonial Hydrology, Christopher L. Pastore, Mark B. Green, Daniel J. Bain, Andrea Muñoz-Hernandez, Charles J. Vörösmarty, Jennifer Arrigo, Sara Brandt, Jonathan M. Duncan, Francesca Greco, Hyojin Kim, Sanjiv Kumar, Michael Lally, Anthony J. Parolari, Brian Pellerin, Nira Salant, Adam Schlosser, Kate Zalzal

Civil and Environmental Engineering Faculty Research and Publications

To properly remediate, improve, or predict how hydrological systems behave, it is vital to establish their histories. However, modern-style records, assembled from instrumental data and remote sensing platforms, hardly exist back more than a few decades. As centuries of data is preferable given multidecadal fluxes of both meteorology/climatology and demographics, building such a history requires resources traditionally considered only useful in the social sciences and humanities. In this Feature, Pastore et al. discuss how they have undertaken the synthesis of historical records and modern techniques to understand the hydrology of the Northeastern U.S. from Colonial times to modern ...


Integration Mechanisms For Heading Perception, Elif M. Sikoglu, Finnegan J. Calabro, Scott A. Beardsley, Lucia M. Vaina 2010 Boston University

Integration Mechanisms For Heading Perception, Elif M. Sikoglu, Finnegan J. Calabro, Scott A. Beardsley, Lucia M. Vaina

Biomedical Engineering Faculty Research and Publications

Previous studies of heading perception suggest that human observers employ spatiotemporal pooling to accommodate noise in optic flow stimuli. Here, we investigated how spatial and temporal integration mechanisms are used for judgments of heading through a psychophysical experiment involving three different types of noise. Furthermore, we developed two ideal observer models to study the components of the spatial information used by observers when performing the heading task. In the psychophysical experiment, we applied three types of direction noise to optic flow stimuli to differentiate the involvement of spatial and temporal integration mechanisms. The results indicate that temporal integration mechanisms play ...


The Effect Of Abductor Muscle And Anterior-Posterior Hip Contact Load Simulation On The In-Vitro Primary Stability Of A Cementless Hip Stem, Youngbae Park, Carolyne Albert, Yong-San Yoon, Göran Fernlund, Hanspeter Frei, Thomas R. Oxland 2010 Korean Advanced Institute of Science and Technology

The Effect Of Abductor Muscle And Anterior-Posterior Hip Contact Load Simulation On The In-Vitro Primary Stability Of A Cementless Hip Stem, Youngbae Park, Carolyne Albert, Yong-San Yoon, Göran Fernlund, Hanspeter Frei, Thomas R. Oxland

Biomedical Engineering Faculty Research and Publications

Background

In-vitro mechanical tests are commonly performed to assess pre-clinically the effect of implant design on the stability of hip endoprostheses. There is no standard protocol for these tests, and the forces applied vary between studies. This study examines the effect of the abductor force with and without application of the anterior-posterior hip contact force in the in-vitro assessment of cementless hip implant stability.

Methods

Cementless stems (VerSys Fiber Metal) were implanted in twelve composite femurs which were divided into two groups: group 1 (N = 6) was loaded with the hip contact force only, whereas group 2 (N = 6) was ...


Ac 2010-475: Development And Implementation Of An Introduction To Stem Course For Dual-Enrollment Programs, Horacio Vasquez, Arturo Fuentes, Javier Macossay-Torres, Martin W. Knecht, Robert Freeman 2010 The University of Texas Rio Grande Valley

Ac 2010-475: Development And Implementation Of An Introduction To Stem Course For Dual-Enrollment Programs, Horacio Vasquez, Arturo Fuentes, Javier Macossay-Torres, Martin W. Knecht, Robert Freeman

Mechanical Engineering Faculty Publications and Presentations

A new Introduction to Science, Technology, Engineering, and Mathematics (STEM) course was developed and taught for the first time during the summer in 2009 to dualenrollment college students at South Texas College (STC). The new Introduction to STEM course was developed in collaboration between STEM Faculty members at the University of Texas-Pan American (UTPA) and STC, with the objective of creating, supporting and strengthening STEM pathways for students in the Dual-Enrollment Engineering Academy (DEEA) and other dual-enrollment or similar programs. The course was offered to two groups of students, at two different campuses in the DEEA program at STC. DEEA ...


Kentucky Traffic Collision Facts 2010 Report, Kentucky Transportation Center, Kentucky State Police 2010 University of Kentucky

Kentucky Traffic Collision Facts 2010 Report, Kentucky Transportation Center, Kentucky State Police

Kentucky Transportation Center Research Report

KENTUCKY’S TRAFFIC COLLISION FACTS report for 2010 is based on collision reports submitted to the Kentucky State Police Records Branch. As required by Kentucky Revised Statutes 189.635, “every law enforcement agency whose officers investigate a vehicle accident of which a report must be made...shall file a report of the accident...within ten days after investigation of the accident upon forms supplied by the bureau.” The stated purpose of this requirement is to utilize data on traffic collisions for such purposes as will improve the traffic safety program in the Commonwealth. Data contained in this report are based ...


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