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2015

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Articles 1 - 30 of 233

Full-Text Articles in Civil and Environmental Engineering

Design And Construction Process Management, David Brown Dec 2015

Design And Construction Process Management, David Brown

David C. Brown

New approaches for improving design and construction processes have been used recently. Innovative methods for managing the requirements and quality of these processes will be discussed. A systematic data centric approach will be discussed as well as the processes of separating progress from performance. It discusses the integration of these processes in the planning, risk analysis, design, submission, construction, inspection, quality control and documentation phases.

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Investigation Into The Properties Of A Cementitious Composite Material Reinforced With Short, Randomly Distributed, Nickel Titanium Fibers, David Brown Dec 2015

Investigation Into The Properties Of A Cementitious Composite Material Reinforced With Short, Randomly Distributed, Nickel Titanium Fibers, David Brown

David C. Brown

No abstract provided.

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The Sustainability Generation: Why Young People Hold The Key To A Better Future, Leidy Klotz Dec 2015

The Sustainability Generation: Why Young People Hold The Key To A Better Future, Leidy Klotz

Leidy E. Klotz

In a standard test of reasoning, you are given a candle, a box of thumbtacks, and a book of matches. Your task is to attach the candle to the wall so that it does not drip onto the table below. I thought about how to melt the wax and use it to stick the candle to the wall. What would you do? This challenge is designed to reveal functional fixedness, mental blocks against using objects in a new way. The experience that comes with age is a disadvantage here because it leads to thinking of the normal use of the …

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A Lean Modeling Protocol For Evaluating Green Project Delivery, Leidy E. Klotz, Michael Horman, Mark Bodenschatz Dec 2015

A Lean Modeling Protocol For Evaluating Green Project Delivery, Leidy E. Klotz, Michael Horman, Mark Bodenschatz

Leidy E. Klotz

The first vital step to leaning an operation is to model or map the processes used to deliver value in that operation. This allows the requisite understanding of where waste and non value-adding activity exists, and provides the foundation for improvement. Current protocols for modeling operations present the basic tenets for lean mapping, but tend to be based in manufacturing language, and are not easily adapted to capital facilities projects. “Green” or “sustainable” capital projects delivered using current project delivery systems seem to be laden with hidden waste. These projects tend to be more challenging to deliver due increased levels …

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Meeting Engineering Program Objectives Through Service Learning Opportunities In Developing Countries, Jeffrey M. Plumblee, Lansford Bell, Leidy E. Klotz Dec 2015

Meeting Engineering Program Objectives Through Service Learning Opportunities In Developing Countries, Jeffrey M. Plumblee, Lansford Bell, Leidy E. Klotz

Leidy E. Klotz

The civil engineering profession, in an adaptive reaction to emerging roles for civil engineers, is recognizing the need for new engineers to possess a more robust skill set than just the typical design background. This paper describes the efforts of Clemson Engineers for Developing Countries (CEDC) to fulfill the more nontraditional and often unaddressed “learning outcomes” noted by ASCE’s Civil Engineering Body of Knowledge for the 21st Century as important prerequisites for licensure. The learning outcomes are addressed through ongoing international service learning projects in Cange, Haiti. The paper focuses on the following four outcomes and their fulfillment methods: leadership, …

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Green Credits Versus Environmentally Sustainable Traffic Operations:A Comparison Of Contributions To Energy And Emissions Reductions, Yan Zhou, Lee Tupper, Mashrur Chowdhury, Leidy Klotz Dec 2015

Green Credits Versus Environmentally Sustainable Traffic Operations:A Comparison Of Contributions To Energy And Emissions Reductions, Yan Zhou, Lee Tupper, Mashrur Chowdhury, Leidy Klotz

Leidy E. Klotz

Although society is facing a variety of environmental issues, including the depletion of energy resources, and has a much greater awareness of climate change and its serious related social impacts, transportation systems have been pushed to increasingly greater limits because of the dramatic growth in traffic demand. A case study was performed to compare the contributions of green construction credits and those of environmentally sustainable traffic operations to reducing energy use and emissions. The study measured the impacts of green credits by using the Carnegie Mellon University economic input-output life-cycle assessment model. These impacts were compared with those achieved through …

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Women As Sustainability Leaders In Engineering: Evidence From Industry And Academia In The U.S., Jennilee Harrison, Leidy Klotz Dec 2015

Women As Sustainability Leaders In Engineering: Evidence From Industry And Academia In The U.S., Jennilee Harrison, Leidy Klotz

Leidy E. Klotz

Women are underrepresented in engineering education and practice, which limits the quality of the engineering workforce. One way to increase the participation of women in engineering is to emphasize subjects that appeal to them and require skills at which they are especially adept. A subject that may fit this description is sustainability. To examine whether the subject of sustainability may help increase the participation of women in engineering, the purpose of this research is to compare the percentage of women in selected sustainable engineering leadership positions with the percentage of women in general engineering leadership positions. Gender data were collected …

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Study Of Structural Performance And Durability Of Concrete By Partial Replacement Of Cement With Hypo Sludge (Paper Waste), K Hari Kishan, N .Vidyasagar Lal,, 3 Sateesh Konni Dec 2015

Study Of Structural Performance And Durability Of Concrete By Partial Replacement Of Cement With Hypo Sludge (Paper Waste), K Hari Kishan, N .Vidyasagar Lal,, 3 Sateesh Konni

Innovative Research Publications IRP India

Utilization of industrial waste products as supplementary cementitious materials (SCM) in concrete making is very important aspect in view of economical, environmental and technical reasons. As these supplementary cementitious materials have different chemical and mineralogical composition, their effect on micro structural properties and strength performance vary considerably. While producing paper, various wastes come out from the various processes in paper industries. The preliminary waste from paper industry is named as hypo sludge. In this study the material obtained from the paper industry waste (hypo sludge) is admixed with Portland cement at different replacement levels. The properties of concrete investigated include …

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House Of Quality (Hoq) Regarding Truck Drivers Requests, Sajjad Khaksari Nov 2015

House Of Quality (Hoq) Regarding Truck Drivers Requests, Sajjad Khaksari

SAJJAD KHAKSARI

"Quality Engineering & Italian Transport Companies" represents a preliminarily attempt to benefit from Quality Engineering methods for analyzing some parts of the real and hidden worlds of some Italian family-owned transport companies. It tries to highlight some things that normally remain neglected regarding the hidden internal workings of some Italian transport companies. In addition, this paper might be interesting for whoever wants to know more about this period in which some Italian family-run transport companies are facing the challenge of a future balancing modernism and traditionalism in their supply chain management (SCM).

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Application Of E-Navigation To Support Ship Operation In Emergency And Routine Situations, Michael Baldauf, Sebastian Klaes, Knud Benedict, Sandro Fischer, Michael Gluch, Matthias Kirchhoff, Michaele Schaub Oct 2015

Application Of E-Navigation To Support Ship Operation In Emergency And Routine Situations, Michael Baldauf, Sebastian Klaes, Knud Benedict, Sandro Fischer, Michael Gluch, Matthias Kirchhoff, Michaele Schaub

Michael Baldauf

No abstract provided.

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New Sensor Technology Integration For Safe And Efficient E-Navigation, Michael Baldauf, R. Glenn Wright Oct 2015

New Sensor Technology Integration For Safe And Efficient E-Navigation, Michael Baldauf, R. Glenn Wright

Michael Baldauf

This paper discusses the relation of new sensor technology on bridge resource management as pertaining to the integration of new information sources and types for ship navigation in a future e-Navigation environment. An overview of several new technologies will be provided showing how systems and devices currently available in the commercial marketplace are being adapted and used to aid ship navigation planning and decision making. Examples include live Doppler radar useful for coastal navigation available from land-based sources through broadband Internet connections, imagery from unmanned aerial vehicles to aid in ice-navigation in, and forward-looking sonar for navigating in poorly charted, …

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Making The Case For Crew-Centered Design (Ccd) In Merchant Shipping, Aditi Kataria, Gesa Praetorius, Jens-Uwe Schröder-Hinrichs, Michael Baldauf Oct 2015

Making The Case For Crew-Centered Design (Ccd) In Merchant Shipping, Aditi Kataria, Gesa Praetorius, Jens-Uwe Schröder-Hinrichs, Michael Baldauf

Michael Baldauf

Since 2003, the International Maritime Organization (IMO) has emphasised the need to address and integrate ergonomics knowledge in a concerted manner. However, there is little guidance on the application of this knowledge in the design of merchant vessels. Utilizing a mixed methods approach, the paper identifies the need for crew-centered design (CCD), highlighting the importance of using concepts derived from Human-Centred Design (HCD) to be able to design work spaces and operational procedures that facilitate the work of the crew on board. Drawing upon results obtained from accident analysis (utilising the Technique for the Retrospective and predictive Analysis of Cognitive …

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From Titanic To Costa Concordia — A Century Of Lessons Not Learned, Jens-Uwe Schröder-Hinrichs, Erik Hollnagel, Michael Baldauf Oct 2015

From Titanic To Costa Concordia — A Century Of Lessons Not Learned, Jens-Uwe Schröder-Hinrichs, Erik Hollnagel, Michael Baldauf

Michael Baldauf

The recent foundering of the Costa Concordia in January 2012 demonstrated that accidents can occur even with ships that are considered masterpieces of modern technology and despite more than 100 years of regulatory and technological progress in maritime safety. The purpose of this paper is, however, not to speculate about the concrete causes of the Costa Concordia accident, but rather to consider some human and organizational factors that were present in the Costa Concordia accident as well as in the foundering of the Titanic a century ago, and which can be found in many other maritime accidents over the years. …

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Making The Case For Crew-Centered Design (Ccd) In Merchant Shipping, Aditi Kataria, Gesa Praetorius, Jens-Uwe Schröder-Hinrichs, Michael Baldauf Oct 2015

Making The Case For Crew-Centered Design (Ccd) In Merchant Shipping, Aditi Kataria, Gesa Praetorius, Jens-Uwe Schröder-Hinrichs, Michael Baldauf

Gesa Praetorius

Since 2003, the International Maritime Organization (IMO) has emphasised the need to address and integrate ergonomics knowledge in a concerted manner. However, there is little guidance on the application of this knowledge in the design of merchant vessels. Utilizing a mixed methods approach, the paper identifies the need for crew-centered design (CCD), highlighting the importance of using concepts derived from Human-Centred Design (HCD) to be able to design work spaces and operational procedures that facilitate the work of the crew on board. Drawing upon results obtained from accident analysis (utilising the Technique for the Retrospective and predictive Analysis of Cognitive …

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Umass Amherst Green Building Guidelines 2013, Ludmilla Pavlova-Gillham, Ted Mendoza, Ezra Small, Patricia O'Flaherty, Nariman Mostafavi, Mohamed Farzinmoghadam, Somayeh Tabatabaee Pozveh Oct 2015

Umass Amherst Green Building Guidelines 2013, Ludmilla Pavlova-Gillham, Ted Mendoza, Ezra Small, Patricia O'Flaherty, Nariman Mostafavi, Mohamed Farzinmoghadam, Somayeh Tabatabaee Pozveh

Ludmilla D Pavlova

Facilities & Campus Services, Sustainable UMass and Campus Planning support sustainability and energy conservation initiatives by providing in-house resources to campus staff as well as designers and contractors working with the University. The UMass Amherst Green Building Guidelines provide a framework for approaching new construction and major renovation projects at UMass Amherst that are undergoing LEED certification by focusing the conversation on green building aspects that are most important to the campus. They are intended to be the beginning of a dynamic conversation between designers, environmental consultants and constructors, university stakeholders, and users of new high performance buildings.

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University Of Massachusetts Amherst 2012-2021 Capital Improvement Projects, Douglas Vigneau, Juanita Holler, John Mathews, Ludmilla Pavlova-Gillham, Ezra Small Oct 2015

University Of Massachusetts Amherst 2012-2021 Capital Improvement Projects, Douglas Vigneau, Juanita Holler, John Mathews, Ludmilla Pavlova-Gillham, Ezra Small

Ludmilla D Pavlova

In 2013 the University of Massachusetts, on behalf of the University of Massachusetts Building Authority and Massachusetts Division of Capital Asset Management and Maintenance (DCAMM), submitted an Expanded Environmental Notification Form for the University's 2012 - 2021 Capital Improvement Plan to the Executive Office of Energy and Environmental Affairs (EOEEA) Massachusetts Environmental Policy Act Office (MEPA). Taken individually, the majority of the Projects, comprising of 13 building/space, 7 site/landscape, and 5 facility/ utility scale improvement projects, do not require MEPA review as most of the Project sites are confined to infill areas on campus that are currently or have been …

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Investigations Of The Presence Of Caffeine In The Rudawa River, Kraków, Poland, Agnieszka Jagoda, Witold Zukowski, Barbara Dąbrowska Oct 2015

Investigations Of The Presence Of Caffeine In The Rudawa River, Kraków, Poland, Agnieszka Jagoda, Witold Zukowski, Barbara Dąbrowska

Witold Zukowski

Caffeine concentration in surface water (Rudawa River, Kraków, Poland) has been being investigated since 2011. The method applied for investigations was developed in 2011, and the first series of measurements of caffeine concentration in surface water began in 2011. Caffeine concentration was determined by the gas chromatography-mass spectrometry (GC-MS) method. Solid phase extraction (SPE) was used to enrich the concentration of caffeine in water samples. As an internal standard, the caffeine isotope (13)C3 in methanol (Sigma Aldrich) was used. The values of four additional parameters (concentration of nitrates, biochemical oxygen demand after 7 days, number of Escherichia coli and number …

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Experimental Validation Of Multistep Quantitative Crack Damage Assessment For Truss Structures By Finite Element Model Updating, Soon Lee, Gunjin Yun, Mohammad Rahimi, Shen Shang Oct 2015

Experimental Validation Of Multistep Quantitative Crack Damage Assessment For Truss Structures By Finite Element Model Updating, Soon Lee, Gunjin Yun, Mohammad Rahimi, Shen Shang

Gunjin Yun

In this paper, a multistep damage quantification method has been experimentally validated by quantifying crack damage of load-carrying members of truss structures based on experimental vibration records. Damage quantifications are still challenging tasks for difficulties in interpreting response signals measured from engineering structures. Open crack depth is parameterized as a damage variable. The open crack in Euler–Bernoulli beam element is modeled by introducing local flexibility coefficients to the uncracked beam element with joint rotational flexibility. Mode shapes and natural frequencies measured from experimental modal testing of a damaged laboratory-size truss bridge are used in the finite element model updating for …

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The Quasi-Static Deformation, Failure, And Fracture Behavior Of Titanium Alloy Gusset Plates Containing Bolt Holes, Therese Hurtuk, Craig Menzemer, Anil Patnaik, Tirumalai Srivatsan, Kannan Manigandan, T. Quick Oct 2015

The Quasi-Static Deformation, Failure, And Fracture Behavior Of Titanium Alloy Gusset Plates Containing Bolt Holes, Therese Hurtuk, Craig Menzemer, Anil Patnaik, Tirumalai Srivatsan, Kannan Manigandan, T. Quick

Craig Menzemer

In this article, the influence of bolt holes, specifically their number and layout on strength, deformation, and final fracture behavior of titanium alloy gusset plates under the influence of an external load is presented and discussed. Several plates having differences in both the number and layout of the bolt holes were precision machined and then deformed under quasi-static loading. The specific influence of number of bolt holes and their layout on maximum load-carrying capability and even fracture load was determined. The conjoint influence of bolt number, bolt layout pattern, nature of loading, contribution from local stress concentration, and intrinsic microstructural …

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The Bolt Bearing Response And Tensile Deformation Capacity Of Plates Made From A Titanium Alloy, Nicholas Tinl, Craig Menzemer, Anil Patnaik, Tirumalai Srivatsan Oct 2015

The Bolt Bearing Response And Tensile Deformation Capacity Of Plates Made From A Titanium Alloy, Nicholas Tinl, Craig Menzemer, Anil Patnaik, Tirumalai Srivatsan

Craig Menzemer

In this article, the bearing capacity and elongation characteristics of bolt holes in a titanium alloy (i.e., Ti-6Al-4V) deformed in uniaxial tension is presented and discussed. The specific role played by bolt hole confinement on bearing capacity is highlighted. The nature of final fracture is examined and the intrinsic features present on the fracture surface are rationalized in concurrence with macroscopic mechanical response. The behavior of the candidate alloy (Ti-6Al-4V) is compared with conventionally preferred and chosen candidate materials steel and aluminum alloys. An empirical relationship suitable for purpose of structural design is proposed.

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Understanding The Mechanical Response Of Built-Up Welded Beams Made From Commercially Pure Titanium And A Titanium Alloy, Anil Patnaik, Narendra Poondla, Craig Menzemer, Tirumalai Srivatsan Oct 2015

Understanding The Mechanical Response Of Built-Up Welded Beams Made From Commercially Pure Titanium And A Titanium Alloy, Anil Patnaik, Narendra Poondla, Craig Menzemer, Tirumalai Srivatsan

Craig Menzemer

During the last two decades, titanium has gradually grown in stature, strength and significance to take on the recognition of being a modern and high performance metal that is noticeably stronger and concurrently lighter than the most widely chosen and used steels in a spectrum of industrial applications. Technological innovations have necessitated reduction of part weight, cost and lead time, including concurrent enhancement of performance of structural parts and components made using titanium and its alloys. This has provided the impetus to develop economically viable structural design methodologies and specifications, while at the same time bringing forth innovative and economically …

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Isolating Corrosion Of Steel Plates Coupled With Titanium, Anil Patnaik, X. Shan, M. Adams, T. Srivatsan, Craig Menzemer, Joe Payer Oct 2015

Isolating Corrosion Of Steel Plates Coupled With Titanium, Anil Patnaik, X. Shan, M. Adams, T. Srivatsan, Craig Menzemer, Joe Payer

Craig Menzemer

Over twenty six percent of the bridges in the United States are structurally deficient or functionally obsolete. Corrosion of steel used in structures like bridges and buildings is a problem that has gained increased interest and focused concern. Steel is often the metal that is preferred for use in such applications due to a synergism of ease of availability, acceptable mechanical properties and cost effectiveness. Through the years, titanium has grown in strength, stature and significance to be recognized as an emerging high performance metal that is both stronger and lighter than steel. A distinctive property of titanium and its …

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Infuence Of Welding And Heat Treatment On Microstructure, Properties And Fracture Behaviour Of A Wrought Aluminium Alloy, Eric Hilty, Craig Menzemer, Kannan Manigandan, Tirumalai Srivatsan Oct 2015

Infuence Of Welding And Heat Treatment On Microstructure, Properties And Fracture Behaviour Of A Wrought Aluminium Alloy, Eric Hilty, Craig Menzemer, Kannan Manigandan, Tirumalai Srivatsan

Craig Menzemer

Welding of aluminium alloy, belonging to the 6XXX series, exerts an adverse influence on its strength. The loss of strength immediately adjacent to the welds can have an influence on overall behaviour of the structure or component. In this study, the technique of gas metal arc welding was used. The filler material used was a silicon-containing aluminium alloy. Subsequent to welding, the alloy (6061-T4) was subjected to post-weld heat treatment (PWHT) at 185°C for 6 h. Both the as-welded and artificially aged extrusions of aluminium alloy 6061 were examined for both microstructural development and resultant influence on mechanical properties. Light …

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Probabilistic Approaches To Stability And Deformation Problems In Braced Excavation, Zhe Luo Oct 2015

Probabilistic Approaches To Stability And Deformation Problems In Braced Excavation, Zhe Luo

Zhe Luo

This dissertation is aimed at applying probabilistic approaches to evaluating the basal-heave stability and the excavation-induced wall and ground movements for serviceability assessment of excavation in clays. The focuses herein are the influence of spatial variability of soil parameters and small sample size on the results of the probabilistic analysis, and Bayesian updating of soil parameters using field observations in braced excavations. Simplified approaches for reliability analysis of basal-heave in a braced excavation in clay considering the effect of spatial variability in random fields are presented. The proposed approaches employ the variance reduction technique (or more precisely, equivalent variance method) …

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An Adaptive Level Set Approach For Modeling Damage Due To Galvanic Corrosion, Joseph Wilder, Curtis Clemons, Dmitry Golovaty, Kevin Kreider, Gerald Young, R. Lillard Sep 2015

An Adaptive Level Set Approach For Modeling Damage Due To Galvanic Corrosion, Joseph Wilder, Curtis Clemons, Dmitry Golovaty, Kevin Kreider, Gerald Young, R. Lillard

Gerald W Young

This article presents an approach to solving problems related to galvanic corrosion that involve moving boundaries (due to preferential corrosion of one of the metals in the system). The method incorporates an adaptive (node based, finite difference) grid technique for the treatment of boundary-related singularities that arise in the calculation of the electric potential. Simulation of the time evolution of the damage done by the corroding interface is performed using of a level set formulation. An analysis of the convergence of the method and a comparison with experimental data from the literature are included.

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An Adaptive Level Set Approach For Modeling Damage Due To Galvanic Corrosion, Joseph Wilder, Curtis Clemons, Dmitry Golovaty, Kevin Kreider, Gerald Young, R. Lillard Sep 2015

An Adaptive Level Set Approach For Modeling Damage Due To Galvanic Corrosion, Joseph Wilder, Curtis Clemons, Dmitry Golovaty, Kevin Kreider, Gerald Young, R. Lillard

Kevin L. Kreider

This article presents an approach to solving problems related to galvanic corrosion that involve moving boundaries (due to preferential corrosion of one of the metals in the system). The method incorporates an adaptive (node based, finite difference) grid technique for the treatment of boundary-related singularities that arise in the calculation of the electric potential. Simulation of the time evolution of the damage done by the corroding interface is performed using of a level set formulation. An analysis of the convergence of the method and a comparison with experimental data from the literature are included.

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An Adaptive Level Set Approach For Modeling Damage Due To Galvanic Corrosion, Joseph Wilder, Curtis Clemons, Dmitry Golovaty, Kevin Kreider, Gerald Young, R. Lillard Sep 2015

An Adaptive Level Set Approach For Modeling Damage Due To Galvanic Corrosion, Joseph Wilder, Curtis Clemons, Dmitry Golovaty, Kevin Kreider, Gerald Young, R. Lillard

Curtis B. Clemons

This article presents an approach to solving problems related to galvanic corrosion that involve moving boundaries (due to preferential corrosion of one of the metals in the system). The method incorporates an adaptive (node based, finite difference) grid technique for the treatment of boundary-related singularities that arise in the calculation of the electric potential. Simulation of the time evolution of the damage done by the corroding interface is performed using of a level set formulation. An analysis of the convergence of the method and a comparison with experimental data from the literature are included.

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Ultrasonic Enhanced Liquefaction And Saccharification Of Corn For Bio-Fuel Production, Samir Kumar Khanal, Melissa T. Montalbo, Johannes Van Leeuwen, Gowrishankar Srinivasan, David A. Grewell Sep 2015

Ultrasonic Enhanced Liquefaction And Saccharification Of Corn For Bio-Fuel Production, Samir Kumar Khanal, Melissa T. Montalbo, Johannes Van Leeuwen, Gowrishankar Srinivasan, David A. Grewell

Gowrishankar Srinivasan

Dry grind corn milling does not reach full efficiency of starch conversion to sugars and subsequently to ethanol because of limitations in the milling process. This paper examines the use of high-power ultrasonics to enhance the release of fermentable sugars from milled dry corn. In this work, 20 kHz ultrasonic energy was used to pretreat corn mash prior to enzymatic conversion of corn starch to glucose in a batch-mode. The ultrasonic amplitude was varied from 0, 191 to 320 µm pp . The corn mash was sonicated for 0 (control), 20 and 40 seconds. Other experimental variables that were studied …

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Experimental And Fem Study Of Thermal Cycling Induced Microcracking In Carbon/Epoxy Triaxial Braided Composites, Chao Zhang, Wieslaw Binienda, Gregory Morscher, Richard Martin, Lee Kohlman Sep 2015

Experimental And Fem Study Of Thermal Cycling Induced Microcracking In Carbon/Epoxy Triaxial Braided Composites, Chao Zhang, Wieslaw Binienda, Gregory Morscher, Richard Martin, Lee Kohlman

Wieslaw K. Binienda

The microcrack distribution and mass change in T700s/PR520 and T700s/3502 carbon/epoxy braided composites exposed to thermal cycling was evaluated experimentally. Acoustic emission was utilized to record the crack initiation and propagation under cyclic thermal loading between −55 °C and 120 °C. Transverse microcrack morphology was investigated using X-ray computed tomography. The differing performance of two kinds of composites was discovered and analyzed. Based on the observations of microcrack formation, a meso-mechanical finite element model was developed to obtain the resultant mechanical properties. The simulation results exhibited a decrease in strength and stiffness with increasing crack density. Strength and stiffness reduction …

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Numerical Analysis Of Free-Edge Effect On Size-Influenced Mechanical Properties Of Single-Layer Triaxially Braided Composites, Chao Zhang, Wieslaw Binienda Sep 2015

Numerical Analysis Of Free-Edge Effect On Size-Influenced Mechanical Properties Of Single-Layer Triaxially Braided Composites, Chao Zhang, Wieslaw Binienda

Wieslaw K. Binienda

The mechanical properties of triaxially braided composites under transverse loads are found to be size-dependent, due to the presence of free-edge effect. Numerical studies of the mechanical behaviors of straight-sided coupon specimens and an infinitely large plate under both axial and transverse tension loads were conducted using a meso-scale finite element model. The numerical model correlates well with experimental results, successfully capturing the free-edge warping phenomena under transverse tension. Free-edge effect is observed as out-of-plane warping, and it can be correlated to the premature damage initiation in the affected area. The numerical results characterize the impact of free-edge effects on …

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