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Full-Text Articles in Engineering

A Benchmark Study On The Thermal Conductivity Of Nanofluids, Jacopo Buongiorno, David C. Venerus, Naveen Prabhat, Thomas Mckrell, Jessica Townsend, Rebecca J. Christianson, Yuriv V. Tolmachev, Pawel Keblinski, Lin-Wen Hu, Jorge L. Alvarado, In Cheol Bang, Sandra W. Bishnoi, Marco Bonetti, Frank Botz, Anselmo Cecere, Yun Chang, Gang Chen, Haisheng Chen, Sung Jae Chung, Minking K. Chyu, Sarit K. Das, Roberto Di Paola, Yulong Ding, Frank Dubois, Grzegorz Dzido, Jacob Eapen, Werner Escher, Denis Funfschilling, Quentin Galand, Jinwei Gao, Patricia E. Gharagozloo, Kenneth E. Goodson, Jorge Gustavo Gutierrez, Haiping Hong, Mark Horton, Kyo Sik Hwang, Carlo S. Iorio, Seok Pil Jang, Andrzej B. Jarzebski, Yiran Jiang, Stephan Kabelac, Liwen Jin, Aravind Kamath, Mark A. Kedzierski, Lim Geok Kieng, Chongyoup Kim, Ji-Hyun Kim, Seokwon Kim, Seung Hyun Lee, Kai Choong Leong, Indranil Manna, Bruno Michel, Rui Ni, Hrishikesh E. Patel, John Philip, Dimos Poulikakos, Cecil Reynaud, Raffaele Savino, Pawan K. Singh, Pengxiang Song, Thirumalachari Sundararajan, Elena Timofeeva, Todd Tritcak, Aleksandr N. Turanov, Stefan Van Vaerenbergh, Dongsheng Wen, Sanjeeva Witharana, Chun Yang, Wei-Hsun Yeh, Xiao-Zheng Zhao, Sheng-Qi Zhou Dec 2011

A Benchmark Study On The Thermal Conductivity Of Nanofluids, Jacopo Buongiorno, David C. Venerus, Naveen Prabhat, Thomas Mckrell, Jessica Townsend, Rebecca J. Christianson, Yuriv V. Tolmachev, Pawel Keblinski, Lin-Wen Hu, Jorge L. Alvarado, In Cheol Bang, Sandra W. Bishnoi, Marco Bonetti, Frank Botz, Anselmo Cecere, Yun Chang, Gang Chen, Haisheng Chen, Sung Jae Chung, Minking K. Chyu, Sarit K. Das, Roberto Di Paola, Yulong Ding, Frank Dubois, Grzegorz Dzido, Jacob Eapen, Werner Escher, Denis Funfschilling, Quentin Galand, Jinwei Gao, Patricia E. Gharagozloo, Kenneth E. Goodson, Jorge Gustavo Gutierrez, Haiping Hong, Mark Horton, Kyo Sik Hwang, Carlo S. Iorio, Seok Pil Jang, Andrzej B. Jarzebski, Yiran Jiang, Stephan Kabelac, Liwen Jin, Aravind Kamath, Mark A. Kedzierski, Lim Geok Kieng, Chongyoup Kim, Ji-Hyun Kim, Seokwon Kim, Seung Hyun Lee, Kai Choong Leong, Indranil Manna, Bruno Michel, Rui Ni, Hrishikesh E. Patel, John Philip, Dimos Poulikakos, Cecil Reynaud, Raffaele Savino, Pawan K. Singh, Pengxiang Song, Thirumalachari Sundararajan, Elena Timofeeva, Todd Tritcak, Aleksandr N. Turanov, Stefan Van Vaerenbergh, Dongsheng Wen, Sanjeeva Witharana, Chun Yang, Wei-Hsun Yeh, Xiao-Zheng Zhao, Sheng-Qi Zhou

Jessica Townsend

This article reports on the International Nanofluid Property Benchmark Exercise, or INPBE, in which the thermal conductivity of identical samples of colloidally stable dispersions of nanoparticles or “nanofluids,” was measured by over 30 organizations worldwide, using a variety of experimental approaches, including the transient hot wire method, steady-state methods, and optical methods. The nanofluids tested in the exercise were comprised of aqueous and nonaqueous basefluids, metal and metal oxide particles, near-spherical and elongated particles, at low and high particle concentrations. The data analysis reveals that the data from most organizations lie within a relatively narrow band (±10% or less) about …


A Benchmark Study On The Thermal Conductivity Of Nanofluids, Jacopo Buongiorno, David Venerus, Naveen Prabhat, Thomas Mckrell, Jessica Townsend, Rebecca Christianson, Yuriv Tolmachev, Pawel Keblinski, Lin-Wen Hu, Jorge Alvarado, In Cheol Bang, Sandra Bishnoi, Marco Bonetti, Frank Botz, Anselmo Cecere, Yun Chang, Gang Chen, Haisheng Chen, Sung Jae Chung, Minking Chyu, Sarit Das, Roberto Di Paola, Yulong Ding, Frank Dubois, Grzegorz Dzido, Jacob Eapen, Werner Escher, Denis Funfschilling, Quentin Galand, Jinwei Gao, Patricia Gharagozloo, Kenneth Goodson, Jorge Gutierrez, Haiping Hong, Mark Horton, Kyo Sik Hwang, Carlo Iorio, Seok Pil Jang, Andrzej Jarzebski, Yiran Jiang, Stephan Kabelac, Liwen Jin, Aravind Kamath, Mark Kedzierski, Lim Geok Kieng, Chongyoup Kim, Ji-Hyun Kim, Seokwon Kim, Seung Hyun Lee, Kai Choong Leong, Indranil Manna, Bruno Michel, Rui Ni, Hrishikesh Patel, John Philip, Dimos Poulikakos, Cecil Reynaud, Raffaele Savino, Pawan Singh, Pengxiang Song, Thirumalachari Sundararajan, Elena Timofeeva, Todd Tritcak, Aleksandr Turanov, Stefan Van Vaerenbergh, Dongsheng Wen, Sanjeeva Witharana, Chun Yang, Wei-Hsun Yeh, Xiao-Zheng Zhao, Sheng-Qi Zhou Dec 2011

A Benchmark Study On The Thermal Conductivity Of Nanofluids, Jacopo Buongiorno, David Venerus, Naveen Prabhat, Thomas Mckrell, Jessica Townsend, Rebecca Christianson, Yuriv Tolmachev, Pawel Keblinski, Lin-Wen Hu, Jorge Alvarado, In Cheol Bang, Sandra Bishnoi, Marco Bonetti, Frank Botz, Anselmo Cecere, Yun Chang, Gang Chen, Haisheng Chen, Sung Jae Chung, Minking Chyu, Sarit Das, Roberto Di Paola, Yulong Ding, Frank Dubois, Grzegorz Dzido, Jacob Eapen, Werner Escher, Denis Funfschilling, Quentin Galand, Jinwei Gao, Patricia Gharagozloo, Kenneth Goodson, Jorge Gutierrez, Haiping Hong, Mark Horton, Kyo Sik Hwang, Carlo Iorio, Seok Pil Jang, Andrzej Jarzebski, Yiran Jiang, Stephan Kabelac, Liwen Jin, Aravind Kamath, Mark Kedzierski, Lim Geok Kieng, Chongyoup Kim, Ji-Hyun Kim, Seokwon Kim, Seung Hyun Lee, Kai Choong Leong, Indranil Manna, Bruno Michel, Rui Ni, Hrishikesh Patel, John Philip, Dimos Poulikakos, Cecil Reynaud, Raffaele Savino, Pawan Singh, Pengxiang Song, Thirumalachari Sundararajan, Elena Timofeeva, Todd Tritcak, Aleksandr Turanov, Stefan Van Vaerenbergh, Dongsheng Wen, Sanjeeva Witharana, Chun Yang, Wei-Hsun Yeh, Xiao-Zheng Zhao, Sheng-Qi Zhou

Rebecca J. Christianson

This article reports on the International Nanofluid Property Benchmark Exercise, or INPBE, in which the thermal conductivity of identical samples of colloidally stable dispersions of nanoparticles or “nanofluids,” was measured by over 30 organizations worldwide, using a variety of experimental approaches, including the transient hot wire method, steady-state methods, and optical methods. The nanofluids tested in the exercise were comprised of aqueous and nonaqueous basefluids, metal and metal oxide particles, near-spherical and elongated particles, at low and high particle concentrations. The data analysis reveals that the data from most organizations lie within a relatively narrow band (±10% or less) about …


From Pollen To Polyester, Debbie Chachra Nov 2011

From Pollen To Polyester, Debbie Chachra

Debbie Chachra

Polyester bees are all over the Northeast. The interesting thing about them is that they dig underground tunnels, about the width of your pinky finger, where they lay their eggs. To protect their larvae from heat, cold, fungus, bacteria and other dangers, the bees line these chambers with a clear, cellophanelike substance. The larvae then live underground for most of their lives in these reinforced cells.


Outcomes Of A Longitudinal Administration Of The Persistence In Engineering Survey, Ozgur Eris, Debbie Chachra, Helen Chen, Sheri Sheppard, Larry Ludlow, Camelia Rosca, Tori Bailey, George Toye Oct 2011

Outcomes Of A Longitudinal Administration Of The Persistence In Engineering Survey, Ozgur Eris, Debbie Chachra, Helen Chen, Sheri Sheppard, Larry Ludlow, Camelia Rosca, Tori Bailey, George Toye

Ozgur Eris

BACKGROUND Understanding more about student decisions to leave engineering may leadto higher retention. This study builds on the literature and focuses on theexperiences of a cohort of students who aimed to complete their undergraduatework in 2007. PURPOSE (HYPOTHESIS) This paper presents the outcomes of the longitudinal administration of thePersistence in Engineering survey. The goal was to identify correlates of persistencein undergraduate engineering education and professional engineeringpractice. DESIGN/METHOD The survey was administered seven times over four years to a cohort of studentswho had expressed interest in studying engineering. At the end of thestudy, the participants were categorized as persisters or non-persisters.Repeated …


Engineering Design Thinking, Teaching, And Learning, Clive Dym, Alice Agogino, Ozgur Eris, Daniel Frey, Larry Leifer Oct 2011

Engineering Design Thinking, Teaching, And Learning, Clive Dym, Alice Agogino, Ozgur Eris, Daniel Frey, Larry Leifer

Ozgur Eris

engineering education is to graduate engineers who can design,and that design thinking is complex. The paper begins by brieflyreviewing the history and role of design in the engineeringcurriculum. Several dimensions of design thinking are thendetailed, explaining why design is hard to learn and harder still toteach, and outlining the research available on how well designthinking skills are learned. The currently most-favoredpedagogical model for teaching design, project-based learning(PBL), is explored next, along with available assessment data onits success. Two contexts for PBL are emphasized: first-yearcornerstone courses and globally dispersed PBL courses. Finally,the paper lists some of the open research questions that …


Outcomes Of A Longitudinal Administration Of The Persistence In Engineering Survey, Ozgur Eris, Debbie Chachra, Helen Chen, Sheri Sheppard, Larry Ludlow, Camelia Rosca, Tori Bailey, George Toye Oct 2011

Outcomes Of A Longitudinal Administration Of The Persistence In Engineering Survey, Ozgur Eris, Debbie Chachra, Helen Chen, Sheri Sheppard, Larry Ludlow, Camelia Rosca, Tori Bailey, George Toye

Debbie Chachra

BACKGROUND Understanding more about student decisions to leave engineering may leadto higher retention. This study builds on the literature and focuses on theexperiences of a cohort of students who aimed to complete their undergraduatework in 2007. PURPOSE (HYPOTHESIS) This paper presents the outcomes of the longitudinal administration of thePersistence in Engineering survey. The goal was to identify correlates of persistencein undergraduate engineering education and professional engineeringpractice. DESIGN/METHOD The survey was administered seven times over four years to a cohort of studentswho had expressed interest in studying engineering. At the end of thestudy, the participants were categorized as persisters or non-persisters.Repeated …


Effect Of Gold Content On The Reliability Of Snagcu Solder Joints, Jianbiao Pan, J. Silk, M. Powers, P. Hyland Oct 2011

Effect Of Gold Content On The Reliability Of Snagcu Solder Joints, Jianbiao Pan, J. Silk, M. Powers, P. Hyland

Jianbiao Pan

Electroplated Ni/Au over Cu is a popular metallization for printed circuit board finish as well as for component leads, especially wire-bondable high-frequency packages, where the gold thickness requirement for wire bonding is high. The general understanding is that less than 3 wt% of Au is acceptable in SnPb solder joints. However, little is known about the effect of Au content on the reliability of SnAgCu solder joints. The purpose of this paper is to determine the acceptable level of Au in SAC305 solder joints. Three different package platforms with different Au thicknesses were assembled on boards with two different Au …


Ena/Vasp Is Required For Endothelial Barrier Function In Vivo, Craig Furman, Alisha L. Sieminski, Adam V. Kwiatkowski, Douglas A. Rubinson, Eliza Vasile, Roderick T. Bronson, Reinhard Fassler Jun 2011

Ena/Vasp Is Required For Endothelial Barrier Function In Vivo, Craig Furman, Alisha L. Sieminski, Adam V. Kwiatkowski, Douglas A. Rubinson, Eliza Vasile, Roderick T. Bronson, Reinhard Fassler

Alisha L. Sarang-Sieminski

Enabled/vasodilator-stimulated phosphoprotein (Ena/VASP) proteins are key actin regulators that localize at regions of dynamic actin remodeling, including cellular protrusions and cell-cell and cell-matrix junctions. Several studies have suggested that Ena/VASP proteins are involved in the formation and function of cellular junctions. Here, we establish the importance of Ena/VASP in endothelial junctions in vivo by analysis of Ena/VASP-deficient animals. In the absence of Ena/VASP, the vasculature exhibits patterning defects and lacks structural integrity, leading to edema, hemorrhaging, and late stage embryonic lethality. In endothelial cells, we find that Ena/VASP activity is required for normal F-actin content, actomyosin contractility, and proper response …


Persistence, Engagement, And Migration In Engineering Programs, Matthew Ohland, Sheri Sheppard, Gary Lichtenstein, Ozgur Eris, Debbie Chachra, Richard Layton Jun 2011

Persistence, Engagement, And Migration In Engineering Programs, Matthew Ohland, Sheri Sheppard, Gary Lichtenstein, Ozgur Eris, Debbie Chachra, Richard Layton

Debbie Chachra

Records from the Multiple-Institution Database forInvestigating Engineering Longitudinal Development indicatethat engineering students are typical of students in other majorswith respect to: persistence in major; persistence by gender andethnicity; racial/ethnic distribution; and grade distribution. Datafrom the National Survey of Student Engagement show that thissimilarity extends to engagement outcomes including course challenge,faculty interaction, satisfaction with institution, and overallsatisfaction. Engineering differs from other majors most notablyby a dearth of female students and a low rate of migration into themajor. Noting the similarity of students of engineering and othermajors with respect to persistence and engagement, we proposethat engagement is a precursor to persistence. We …


Analysis Of Electroluminescence Spectra Of Silicon And Gallium Arsenide P-N Junctions In Avalanche Breakdown, M Lahbabi, A Ahaitoufa, M. Fliyou, E. Abarkan, J.-P. Charles, A. Bath, A. Hoffmann, Sherra Kerns, David Kerns, Jr. Jun 2011

Analysis Of Electroluminescence Spectra Of Silicon And Gallium Arsenide P-N Junctions In Avalanche Breakdown, M Lahbabi, A Ahaitoufa, M. Fliyou, E. Abarkan, J.-P. Charles, A. Bath, A. Hoffmann, Sherra Kerns, David Kerns, Jr.

David V. Kerns

We present a generalized study of light emission from reverse biased p–n junctions under avalanche breakdown conditions. A model is developed based on direct and indirect interband processes including self-absorption to describe measured electroluminescence spectra. This model was used to analyze experimental data for silicon (Si) and gallium arsenide p–n junctions and can be extended to several types of semiconductors regardless of their band gaps. This model can be used as a noninvasive technique for the determination of the junction depth. It has also been used to explain the observed changes of the Si p–n junction electroluminescence spectra after fast …


Analysis Of Electroluminescence Spectra Of Silicon And Gallium Arsenide P-N Junctions In Avalanche Breakdown, M Lahbabi (Adjunct), A Ahaitoufa, M. Fliyou, E. Abarkan, J.-P. Charles, A. Bath, A. Hoffmann, Sherra E. Kerns, David V. Kerns, Jr. Jun 2011

Analysis Of Electroluminescence Spectra Of Silicon And Gallium Arsenide P-N Junctions In Avalanche Breakdown, M Lahbabi (Adjunct), A Ahaitoufa, M. Fliyou, E. Abarkan, J.-P. Charles, A. Bath, A. Hoffmann, Sherra E. Kerns, David V. Kerns, Jr.

Sherra E. Kerns

We present a generalized study of light emission from reverse biased p–n junctions under avalanche breakdown conditions. A model is developed based on direct and indirect interband processes including self-absorption to describe measured electroluminescence spectra. This model was used to analyze experimental data for silicon (Si) and gallium arsenide p–n junctions and can be extended to several types of semiconductors regardless of their band gaps. This model can be used as a noninvasive technique for the determination of the junction depth. It has also been used to explain the observed changes of the Si p–n junction electroluminescence spectra after fast …


Instability Of Electrokinetic Microchannel Flows With Conductivity Gradients, Hao Lin, Brian D. Storey, Michael H. Oddy, Chuan-Hua Chen, Juan G. Santiago Mar 2011

Instability Of Electrokinetic Microchannel Flows With Conductivity Gradients, Hao Lin, Brian D. Storey, Michael H. Oddy, Chuan-Hua Chen, Juan G. Santiago

Brian Storey

Electrokinetic flow is leveraged in a variety of applications, and is a key enabler of on-chip electrophoresis systems. An important sub-class of electrokinetic devices aim to pump and control electrolyte working liquids with spatial gradients in conductivity. These high-gradient flows can become unstable under the application of a sufficiently strong electric field. In this work the instability physics is explored using theoretical and numerical analyses, as well as experimental observations. The flow in a long, rectangular-cross-section channel is considered. A conductivity gradient is assumed to be orthogonal to the main flow direction, and an electric field is applied in the …


Radial Response Of Individual Bubbles Subjected To Shock Wave Lithotripsy Pulses In Vitro, Thomas J. Matula, Paul R. Hilmo, Brian D. Storey, Andrew J. Szeri Mar 2011

Radial Response Of Individual Bubbles Subjected To Shock Wave Lithotripsy Pulses In Vitro, Thomas J. Matula, Paul R. Hilmo, Brian D. Storey, Andrew J. Szeri

Brian Storey

Direct measurements of individual bubble oscillations in lithotripsy fields have been performed using light-scattering techniques. Studies were performed with bubble clouds in gassy water as well as single levitated bubbles in degassed water. There is direct evidence that the bubble survives the inertial collapse, rebounding several times before breaking up. Bubble dynamics calculations agree well with the observations, provided that vapor trapping (a reduction in condensation during bubble collapse) is included. Furthermore, the afterbounces are dominated by vapor diffusion, not gas diffusion. Vapor trapping is important in limiting the collapse strength of bubbles, and in sonochemical activity. © 2010 American …


Heat And Mass Transfer During The Violent Collapse Of Nonshperical Bubbles, Andrew Szeri, Brian Storey, Antony Pearson, John Blake Mar 2011

Heat And Mass Transfer During The Violent Collapse Of Nonshperical Bubbles, Andrew Szeri, Brian Storey, Antony Pearson, John Blake

Brian Storey

The very high speed of collapse of cavitation bubbles is responsible for a number of phenomena of interest in science and engineering: Luminescence, sonochemistry, cavitation damage, ultrasonic cleaning, etc. Strongly forced bubbles may collapse with such violence that the relatively slow processes of diffusion of the heat of compression and of excess vapor to the bubble wall are obviated. This leads to an approximately adiabatic system with nearly constant mass during the final stages of extreme collapses, accompanied by the evolution of sharp thermal and compositional boundary layers on either side of the interface. It is shown that the boundary …


If Emulation Is Representation, Does Detail Matter?, Lynn Stein Mar 2011

If Emulation Is Representation, Does Detail Matter?, Lynn Stein

Lynn Andrea Stein

One property of the emulator framework presented by Grush is that imagery operates off-line. Contrary to this viewpoint, we present evidence showing that mental rotation of a simple figure modulates low-level features of drawing articulation. This effect is dependent upon the type of rotation, suggesting a more integrative online role for imagery than proposed by the target article.


Making The Human Dimensions Of Sustainable Community Development Visible To Engineers, Juan Lucena, Jen Schneider, Jon A. Leydens Mar 2011

Making The Human Dimensions Of Sustainable Community Development Visible To Engineers, Juan Lucena, Jen Schneider, Jon A. Leydens

Jen Schneider

Recently, engineers – particularly those working on sustainability-related initiatives – have increasingly turned their efforts towards under-served communities. This paper summarises the findings in Engineering and Sustainable Community Development (Juan Lucena et al., 2010) aimed at a diversity of these efforts which are grouped here under the term ‘engineering to help’. These initiatives often exist under names such as community service, humanitarian engineering, and engineers without borders or activities such as the Institution of Civil Engineers' co-sponsored workshop ‘Helping local communities to help themselves’. Although there has been a blossoming of engineering-to-help-related programmes around the world, there is a …


Experimental And Molecular Dynamics Investigation Into The Amphiphilic Nature Of Sulforhodamine B, Baris E. Polat, Shangchao Lin, Jonathan D. Mendenhall, Brett Vanveller, Robert Langer, Daniel Blankschtein Jan 2011

Experimental And Molecular Dynamics Investigation Into The Amphiphilic Nature Of Sulforhodamine B, Baris E. Polat, Shangchao Lin, Jonathan D. Mendenhall, Brett Vanveller, Robert Langer, Daniel Blankschtein

Brett VanVeller

Sulforhodamine B (SRB), a common fluorescent dye, is often considered to be a purely hydrophilic molecule, having no impact on bulk or interfacial properties of aqueous solutions. This assumption is due to the high water solubility of SRB relative to most fluorescent probes. However, in the present study, we demonstrate that SRB is in fact an amphiphile, with the ability to adsorb at an air/water interface and to incorporate into sodium dodecyl sulfate (SDS) micelles. In fact, SRB reduces the surface tension of water by up to 23 mN/m, and the addition of SRB to an aqueous SDS solution induces …


Motivating Technical Writing Through Study Of The Environment, J. Linsdell, Thalia Anagnos Jan 2011

Motivating Technical Writing Through Study Of The Environment, J. Linsdell, Thalia Anagnos

Thalia Anagnos

Today’s engineers must be more than just technically competent. To be successful in our increasingly global economy in which teamwork and interdisciplinary interaction are the norm, engineers must have excellent communication skills. In recognition of industry needs, the San José State University College of Engineering redesigned its technical communication course to ensure that students graduate with writing and speaking skills that will transfer readily to their career needs and the global arena. The course aims to motivate students through exploring topics that are meaningful to them and using communication formats that they will see in the workplace. Combing technical communication …


Putting Partnership First: A Dialogue Model For Science And Risk Communication, Jen Schneider, Roel Snieder Jan 2011

Putting Partnership First: A Dialogue Model For Science And Risk Communication, Jen Schneider, Roel Snieder

Jen Schneider

In April 2010, the New York Times reported that Vattenfall AB, an energy company owned by the Swedish government, had built one of the first coal-fired power plants designed to capture ~90% of the CO2 it produced, with plans to sequester that CO2 underground in geologic repositories near its plant in Brandenburg, Germany (Voosen, 2010). By most measures, if the plant's operations were proven to be successful, it could have served as a model for other carbon capture and sequestration plants worldwide.