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Full-Text Articles in Engineering

Correlating Mechanics Of Materials Student Performance With Scores Of A Test Over Prerequisite Material, Nicholas Alan Smith, Roy Y. Myose, Syed J. Raza, Elizabeth Rollins Oct 2020

Correlating Mechanics Of Materials Student Performance With Scores Of A Test Over Prerequisite Material, Nicholas Alan Smith, Roy Y. Myose, Syed J. Raza, Elizabeth Rollins

ASEE North Midwest Section Annual Conference 2020 Publications

Background – It can be difficult to differentiate the effects of curriculum and instructional changes from differences in student preparation and capabilities. Purpose – In this work we will determine whether a test over prerequisite material from Statics and Calculus can be useful in predicting performance in Mechanics of Materials courses.
Method –This “pre-test” involves the application of concepts and knowledge through problem solving rather than multiple-choice questions alone. This pre-test was administered to 692 students in 19 sections taught by three different instructors over four years at Wichita State University.
Conclusions – Results show that pre-test scores given …


A Hybrid Mechanics Of Materials Course Part 2: Study Of The Effect Of A Sudden Change To Fully-Online Format, Roy Y. Myrose, Elizabeth Rollins Oct 2020

A Hybrid Mechanics Of Materials Course Part 2: Study Of The Effect Of A Sudden Change To Fully-Online Format, Roy Y. Myrose, Elizabeth Rollins

ASEE North Midwest Section Annual Conference 2020 Publications

The recent COVID-19 health crisis caused universities worldwide to move suddenly to an online format during the middle of the spring semester. This change in class format provides a unique opportunity to study the effect of this abrupt shift to online learning on student performance. In order to develop a baseline, the performance of 79 students in two sections of a hybrid Mechanics of Materials course during the face-to-face portion in the spring of 2020 was compared to the past performance of 461 students in 13 sections taught by the same instructor in a similar fashion. Using this comparison as …


Implementing Professional Skills Training In Stem: A Review Of The Literature, Ann M. Gansemer-Topf, Qing Li, Shan Jiang, Guk E. Okudan-Kremer, Nigel Forest Reuel Oct 2020

Implementing Professional Skills Training In Stem: A Review Of The Literature, Ann M. Gansemer-Topf, Qing Li, Shan Jiang, Guk E. Okudan-Kremer, Nigel Forest Reuel

ASEE North Midwest Section Annual Conference 2020 Publications

Background: Project management and other professional skill training is often lacking in graduate student education, typically as a result of limited resources, lack of faculty buy-in, and narrow focus on thesis research. To address this need and with support from NSF, we are developing the Graduates for Advancing Professional Skills (GAPS) program at Iowa State University. To aid the initial development of this program, we conducted a literature review to understand the current context of the development and implementation of professional skills in higher education curricula, with specific interest in STEM fields.
Purpose: The purpose of our study was …


Revising A Portfolio Initiative To Assess Student Progress In A Mechanical Engineering Program, Nancy B. Barr Oct 2020

Revising A Portfolio Initiative To Assess Student Progress In A Mechanical Engineering Program, Nancy B. Barr

ASEE North Midwest Section Annual Conference 2020 Publications

Background: This work-in-progress paper describes an effort to modify a pre-existing course portfolio initiative in a large mechanical engineering undergraduate program to be used for multiple forms of program assessment while maintaining its value as a student learning tool.
Purpose: This paper aims to outline the process that an ad-hoc department committee used to define what it wanted to assess in a required four-course second and third-year problem-based learning sequence by reviewing various rubric options.
Design: Deciding what to assess and what language to use in a rubric involved a series of facilitated discussions.
Results: Following a mock assessment exercise, …


A Community Of Practice Approach To Integrating Professional Skills Training With Graduate Thesis Research, Shan Jiang, Ann M. Gansemer-Topf, Nigel Forest Reuel, Gul E. Okudan-Kremer, Qing Li, Rebecca Mort Oct 2020

A Community Of Practice Approach To Integrating Professional Skills Training With Graduate Thesis Research, Shan Jiang, Ann M. Gansemer-Topf, Nigel Forest Reuel, Gul E. Okudan-Kremer, Qing Li, Rebecca Mort

ASEE North Midwest Section Annual Conference 2020 Publications

Background. It is well recognized that current graduate education is too narrowly focused on thesis research. Graduate students have a strong desire to gain skills for their future career success beyond thesis research. This obvious gap in professional skill training in current graduate study also leads to the common student perception that professional skills beyond academic knowledge should only be gained after completion of thesis research.
Purpose. A new program is being developed to rigorously integrate professional skills training with thesis research. The approach is to establish learning communities of Graduates for Advancing Professional Skills (GAPS) to incorporate project management …


The Investigation Of The Relationship Between Emotional Engagement And Creativity, Elif Elcin Gunay, Chih-Yuan Chu, Liyuani De Jesus Delgado Tapia, Omar El Menoufy, Ani Yam, Shibani Raje, Rafal Jonczyk, Danille S. Dickson, Janet Van Hell, Zahed Siddique, Gul E. Okudan-Kremer Oct 2020

The Investigation Of The Relationship Between Emotional Engagement And Creativity, Elif Elcin Gunay, Chih-Yuan Chu, Liyuani De Jesus Delgado Tapia, Omar El Menoufy, Ani Yam, Shibani Raje, Rafal Jonczyk, Danille S. Dickson, Janet Van Hell, Zahed Siddique, Gul E. Okudan-Kremer

ASEE North Midwest Section Annual Conference 2020 Publications

Background - One of the most critical challenges in engineering education is improving students’ divergent thinking skills. Usually, we observe students’ fixating on only one single solution for engineering problems. However, their ability to think outside the box and provide alternative solutions should be developed. Research shows that engagement may foster the development of thoughts and boost creativity.
Purpose/Hypothesis – Our aim was to investigate students’ engagement with tasks that inspire different facets of creativity (verbal, numeric, and visual). Considering the role of demographics in student engagement, we explored the relationship between their engagement level and demographic traits such as …


Correlation Of Student Participation In Practice Exams And Actual Exam Performance, Antonette T. Cummings Oct 2020

Correlation Of Student Participation In Practice Exams And Actual Exam Performance, Antonette T. Cummings

ASEE North Midwest Section Annual Conference 2020 Publications

Background: Practice exams are a type of formative feedback. These can be administered through learning management systems such as D2L and Canvas as low stakes assessment. This paper intends to show the relationship between students’ participation in online practice exams and their scores on the actual exams.
Research Questions: Does participation in timed, online practice exams correlate with improved actual exam performance on similar questions? Does a correct answer in a timed, online practice exam correlate with obtaining the correct answer on the actual exam on a similar question? Does participation in timed, online practice exams correlate with improved overall …


Faculty And Student Perceptions On Shared Teaching Materials For Advanced Manufacturing (Stam): Building Momentum Through Workshops, Richard Wysk, Gul E. Okudan Kremer Oct 2020

Faculty And Student Perceptions On Shared Teaching Materials For Advanced Manufacturing (Stam): Building Momentum Through Workshops, Richard Wysk, Gul E. Okudan Kremer

ASEE North Midwest Section Annual Conference 2020 Publications

In this paper, we summarize the outcomes of the two workshops aimed at speeding up the transition of research-based advanced manufacturing knowledge into course curriculum for technology and engineering programs. Advanced manufacturing technologies have opened up the realm for new products that only a decade ago were considered unproducible. For example metals 3D Printing has almost no geometric limitations, which allows engineers to develop mesh–based products. Unfortunately, the educational system that serves to educate the majority of manufacturing technicians and engineers still utilizes many of the same curriculum resources for these emerging areas (textbooks, traditional lectures, etc.), frequently creating an …


Engineered Full-Length Fibronectin-Hyaluronic Acid Hydrogels For Stem Cell Engineering., Sara Trujillo, Sebastian Vega, Kwang Hoon Song, Ana San Félix, Matthew J Dalby, Jason A Burdick, Manuel Salmeron-Sanchez Oct 2020

Engineered Full-Length Fibronectin-Hyaluronic Acid Hydrogels For Stem Cell Engineering., Sara Trujillo, Sebastian Vega, Kwang Hoon Song, Ana San Félix, Matthew J Dalby, Jason A Burdick, Manuel Salmeron-Sanchez

Henry M. Rowan College of Engineering Departmental Research

Mechanical cues induce a variety of downstream effects on cells, including the regulation of stem cell behavior. Cell fate is typically characterized on biomaterial substrates where mechanical and chemical properties can be precisely tuned; however, most of these substrates do not recapitulate the biological complexity of the extracellular matrix (ECM). Here, hydrogels are engineered for mechanobiological studies using two major components of the ECM: hyaluronic acid (HA) and fibronectin (FN). Rather than typical surface chemisorption of FN to substrates, the system contains full-length FN covalently crosslinked to HA throughout the hydrogel. The control over the mechanical properties of the hydrogel …


Increasing Concurrence Of Wildfire Drivers Tripled Megafire Critical Danger Days In Southern California Between 1982 And 2018, Mohammad Sadegh Khorshidi, Philip E. Dennison, Mohammad Reza Nikoo, Amir Aghakouchak, Charles H. Luce, Mojtaba Sadegh Oct 2020

Increasing Concurrence Of Wildfire Drivers Tripled Megafire Critical Danger Days In Southern California Between 1982 And 2018, Mohammad Sadegh Khorshidi, Philip E. Dennison, Mohammad Reza Nikoo, Amir Aghakouchak, Charles H. Luce, Mojtaba Sadegh

Civil Engineering Faculty Publications and Presentations

Wildfire danger is often ascribed to increased temperature, decreased humidity, drier fuels, or higher wind speed. However, the concurrence of drivers—defined as climate, meteorological and biophysical factors that enable fire growth—is rarely tested for commonly used fire danger indices or climate change studies. Treating causal factors as independent additive influences can lead to inaccurate inferences about shifting hazards if the factors interact as a series of switches that collectively modulate fire growth. As evidence, we show that in Southern California very large fires and 'megafires' are more strongly associated with multiple drivers exceeding moderate thresholds concurrently, rather than direct relationships …


Data And Analysis Toolbox For Modeling The Nexus Of Food, Energy, And Water, Mojtaba Sadegh, Arvin Farid Oct 2020

Data And Analysis Toolbox For Modeling The Nexus Of Food, Energy, And Water, Mojtaba Sadegh, Arvin Farid

Civil Engineering Faculty Publications and Presentations

Energy, water, and food resources are highly interdependent. Agricultural irrigation accounts for 84% of global consumptive freshwater use, the food supply chain demands up to 30% of global primary energy use, and roughly 80% of global electricity generation depends on water for cooling (an average of nearly 100 L of water withdrawn per kWh). Improving understanding of the complex interactions of this resource nexus is, therefore, a top priority for human well-being, sustainable development, and policymaking. Here, we present an interactive analysis toolbox, Nexus of Food, Energy, and Water (NeFEW), that synthesizes available global data to …


A Mathematical Framework For Estimating Risk Of Airborne Transmission Of Covid-19 With Application To Face Mask Use And Social Distancing, Rajat Mittal, Charles Meneveau, Wen Wu Oct 2020

A Mathematical Framework For Estimating Risk Of Airborne Transmission Of Covid-19 With Application To Face Mask Use And Social Distancing, Rajat Mittal, Charles Meneveau, Wen Wu

Faculty and Student Publications

© 2020 Author(s). A mathematical model for estimating the risk of airborne transmission of a respiratory infection such as COVID-19 is presented. The model employs basic concepts from fluid dynamics and incorporates the known scope of factors involved in the airborne transmission of such diseases. Simplicity in the mathematical form of the model is by design so that it can serve not only as a common basis for scientific inquiry across disciplinary boundaries but it can also be understandable by a broad audience outside science and academia. The caveats and limitations of the model are discussed in detail. The model …


Santa Clara Magazine, Volume 61 Number 3, Fall 2020 [Print Issue V.61:2], Santa Clara University Oct 2020

Santa Clara Magazine, Volume 61 Number 3, Fall 2020 [Print Issue V.61:2], Santa Clara University

Santa Clara Magazine

16 - THE GIFT Is sacrifice, given willingly and with love, what makes us human? Leslie Griffy.

20 - NOT A MOMENT, BUT A MOVEMENT From protests in Benson in 1969 to a multi-decade movement called Unity, students of color have consistently pushed SCU to progress. Matt Morgan.

28 - ON BEING BETTER Discover the ways we can better support each other, particularly as white people seek to become allies to people of color. Lauren Loftus.

32 - THE SACRIFICIAL TWEET Social media missteps are costly, perhaps now more than ever. Just what are we willing to give up to …


Wind Hazard Resilient Construction Mitigation Decision-Making Using A Multi-Objective Optimization, Erin Gregory Oct 2020

Wind Hazard Resilient Construction Mitigation Decision-Making Using A Multi-Objective Optimization, Erin Gregory

Masters Theses & Specialist Projects

While storms worsen and damage to homes increases, limited information is available about mitigations that are effective in lessening damage to homes and/or buildings. Information on past storms exists within FEMA’s Hazus-MH application, but the information provided by the data within the Hazus-MH application, while very informative on its own, was decidedly more precise and useful when optimized to provide defined information to those responsible for determining building codes or regulations for homes.

The research available from Hazus-MH details results from past storms categorized by building type, mitigations, and intensity of disaster. The data can be used to simulate storm …


Novel Application Of Graphene Oxide Based-Biosensor Utilizing Crispr/Dcas9 For Rapid Detection Of Antibiotic Resistance Genes, Joel Omage Oct 2020

Novel Application Of Graphene Oxide Based-Biosensor Utilizing Crispr/Dcas9 For Rapid Detection Of Antibiotic Resistance Genes, Joel Omage

Masters Theses & Specialist Projects

Antibiotic resistance is one of the biggest public health challenges globally. To combat this threat, we have designed a method for the facile and rapid detection of antibiotic resistance gene (ARG) in bacteria. We utilized an emerging tool termed the clusters of regularly interspaced short palindromic repeats (CRISPR) in complex with deactivated CRISPR associated proteins (dCas9) on conjugated 2-dimensional graphene oxide (GO) sheets. Nuclease-deactivated Cas9 in complex with customized single guided RNA (sgRNA) was used for the target DNA recognition. The sgRNA was easy to design and we demonstrated that it is complementary to its target sequence by performing a …


Utilization Of Lidar Technology To Assess Vertical Clearances Of Civil Infrastructure, Daniel Levi Mcintosh Oct 2020

Utilization Of Lidar Technology To Assess Vertical Clearances Of Civil Infrastructure, Daniel Levi Mcintosh

Masters Theses & Specialist Projects

The issue of vertical clearances along highway systems impact the functionality of the road network. Extracting current routing clearances for each structure can be a challenging and hazardous task. Pavement changes and roadway rehabilitation projects can alter roadway geometry, complicating efforts to maintain accurate clearance databases. Vertical clearance measurements may vary from one lane to another beneath overhead structures and are often difficult to obtain due to high traffic volumes. Inherently, traditional methods that are used to obtain the measurements routinely impede the flow of traffic and subject workers to dangerous environments. This study will examine the use of a …


Dual Target Optimization Of Two-Dimensional Truss Using Cost Efficiency And Structural Reliability Sufficiency, Mohammad Rezaee, Seyed Hooman Ghasemi, Mansoureh Rezaee Oct 2020

Dual Target Optimization Of Two-Dimensional Truss Using Cost Efficiency And Structural Reliability Sufficiency, Mohammad Rezaee, Seyed Hooman Ghasemi, Mansoureh Rezaee

Henry M. Rowan College of Engineering Departmental Research

The main contribution of this study is to open a discussion regarding the structural optimization associated with the cost efficiency and structural reliability sufficiency consideration. To do so, several various optimization approaches are investigated to deliberate both cost and reliability concerns. Particularly, particle swarm optimization is highlighted as a reliable optimization approach. Accordingly, an illustrative example is rendered to compare the feasibility of the considered optimization approaches. The feasibility of the investigated approaches is evaluated using the cost and reliability analysis. For the considered example, it was observed that the PSO optimization algorithm has multiple advantages such as easy realization, …


Titan: Uncovering The Paradigm Shift In Security Vulnerability At Near-Threshold Computing, Prabal Basu, Pramesh Pandey, Aatreyi Bal, Chidhambaranathan Rajamanikkam, Koushik Chakraborty, Sanghamitra Roy Oct 2020

Titan: Uncovering The Paradigm Shift In Security Vulnerability At Near-Threshold Computing, Prabal Basu, Pramesh Pandey, Aatreyi Bal, Chidhambaranathan Rajamanikkam, Koushik Chakraborty, Sanghamitra Roy

Electrical and Computer Engineering Faculty Publications

In this paper, we investigate the emerging security threats at Near-Threshold Computing (NTC) that are poised to jeopardize the trustworthy operation of future low-power electronic devices. A substantial research effort over the last decade has bolstered energy efficient operation in low-power computing. However, innovation in low-power security has received only marginal attention, thwarting a ubiquitous adoption of critical Internet of Things applications, such as wearable gadgets. Using a cross-layer methodology, we demonstrate that the timing fault vulnerability of a circuit rapidly increases as the operating conditions of the transistor devices shift from super-threshold to near-threshold values. Exploiting this vulnerability, we …


Manual For Thin Asphalt Overlays, Lerose Lane, R. Gary Hicks, Dingxin Cheng, Erik Updyke Oct 2020

Manual For Thin Asphalt Overlays, Lerose Lane, R. Gary Hicks, Dingxin Cheng, Erik Updyke

Mineta Transportation Institute

This manual presents best practices on project selection, mix design, and construction to ensure a superior product when constructing thin asphalt overlays. Experience shows these treatments provide excellent performance when placed on pavements in fair to good condition using proper construction techniques. Though sometime referred to by other names, thin asphalt overlays have been widely used for pavement preservation throughout the world for over 50 years.

Limited infrastructure funding at the local, state, and federal levels has resulted in greater emphasis on the use of pavement preservation techniques to extend pavement life and reduce maintenance costs. Thin asphalt overlays are …


Combined Numerical And Experimental Determination Of Ball Bearing Capacitances For Bearing Current Prediction, Peng Han, Greg Heins, Dean Patterson, Mark Theile, Dan M. Ionel Oct 2020

Combined Numerical And Experimental Determination Of Ball Bearing Capacitances For Bearing Current Prediction, Peng Han, Greg Heins, Dean Patterson, Mark Theile, Dan M. Ionel

Electrical and Computer Engineering Faculty Publications

High-frequency voltages across the steel ball bearings and the corresponding currents can cause premature bearing failures in electric machines driven by PWM converters. The bearing voltage, one of the most commonly-used failure indicators, depends heavily on the bearing capacitance. This paper presents a combined numerical and experimental approach for the calculation of ball bearing capacitances to address the uncertainty introduced by lubricant property, lubrication status and other metal parts, such as seals and ball retainers. Based on the obtained capacitance breakdown, the influences of temperature, speed and bearing load (radial, axial or combined) on the capacitance are studied. Measurements and …


New Glass Ceramics Are Taken According To The Recipe - Fly Ash, Feni Slag And Glass Waste, University For Business And Technology - Ubt Oct 2020

New Glass Ceramics Are Taken According To The Recipe - Fly Ash, Feni Slag And Glass Waste, University For Business And Technology - Ubt

UBT International Conference

In this study we will present the data from the preliminary preparation of the mixture - the recipe for fly ash which is released from the burning of lignite, ferronickel slag and glass waste as well as the results from the validation of the validity of these constituents according to the previously designed reports. Glass- ceramics are polycrystalline materials produced through the so-called "controlled crystallization process" and share many features between ceramics and glass. It consists of an amorphous phase and one or more glass phases. The whole process of producing these materials passes through the "glass crystallization control", and …


Typological Classification Of Existing Masonry Structures In Debar, Gostivar And Kicevo -North Macedonia, Yasemin Hodza Oct 2020

Typological Classification Of Existing Masonry Structures In Debar, Gostivar And Kicevo -North Macedonia, Yasemin Hodza

UBT International Conference

In North Macedonia there are a large number of masonry structures that built before the existence of the seismic design regulations. Most of the existing masonry structures are single-family houses, in addition there are many public buildings. Within the research, a typological classification of existing masonry structures will be made in order to assess the seismic risk of the selected region. From the existing building fund, the buildings intended for housing are selected for typological classifications. In this context, Debar, Kicevo and Gostivar were selected, which lie on the active fault zones passing through North Macedonia. Seismic risk assessment is …


Engaging Farmers And The Agriculture Industry Through The Testing Agricultural Performance Solutions Program, Charles A. Burr, Daran Rudnick, Matt Stockton, Robert Tigner, Krystle Rhoades Oct 2020

Engaging Farmers And The Agriculture Industry Through The Testing Agricultural Performance Solutions Program, Charles A. Burr, Daran Rudnick, Matt Stockton, Robert Tigner, Krystle Rhoades

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The University of Nebraska–Lincoln Testing Agricultural Performance Solutions (TAPS) program involves use of farm management competitions to increase engagement across producers, industry, and universities.Participants make several management decisions throughout the growing season in a controlled field trial held at the university research station. Results are analyzed, and awards are presented for most profitable farm, most efficient farm, and farm with the greatest grain yield. The TAPS program involves several techniques for facilitating participatory assistance, including two-way communication and transformational learning. It has resulted in participants' questioning their past management decisions and realizing that they need to improve their marketing skills …


Dual-Band Printed Monopole Antenna Design, Hassan Ali Ragheb, Shady Abd-Elaal, Afaaf Saad, Ahmed Zaalouk Oct 2020

Dual-Band Printed Monopole Antenna Design, Hassan Ali Ragheb, Shady Abd-Elaal, Afaaf Saad, Ahmed Zaalouk

Electrical Engineering

Design procedure of a high gain dual-band printed monopole antenna, resonating at 2.4 GHz and 5.5 GHz, is presented. The proposed design meets the specifications required by WI-FI, WIMAX and radio frequency identification (RFID) reader applications. Our design utilizes Rogers RT/Duroid 5880(tm) substrate, and the major radiation element is an annular circular patch shape. The design was improved by adding a face-to-face fork shape metal inside the annular circular patch. The antenna feed consists of a microstrip line and a slotted transformer section for matching purpose. A prototype of the proposed antenna was fabricated and the measurements of the return …


Phytoremediation Of Mining Contaminated Soil And Groundwater By Hemp (Cannabis Sativa L.) And Locally Adapted Native Plants, Nathan Carpenter Oct 2020

Phytoremediation Of Mining Contaminated Soil And Groundwater By Hemp (Cannabis Sativa L.) And Locally Adapted Native Plants, Nathan Carpenter

Graduate Theses & Non-Theses

Phytoremediation is an environmentally friendly and cost-effective method of using plants to remediate soils and groundwater by extracting and accumulating contaminants in their tissues. Using locally adapted native plants is preferable to non-native species due to native species being accustomed to the environmental conditions allowing for increased plant growth and fitness. It is typical to use hyperaccumulator plant species since they will grow in soils with very high concentrations of metals and metalloids and show efficient ability to recover (phytoextraction potential) and accumulate (bioconcentration factor) the contaminants in its tissues.

This study focuses on using thirteen locally adapted native plant …


Use Of Shotcrete Made With Mine Waste To Reduce Costs And Environmental Impacts Of Waste Disposal, Casey Penney Oct 2020

Use Of Shotcrete Made With Mine Waste To Reduce Costs And Environmental Impacts Of Waste Disposal, Casey Penney

Graduate Theses & Non-Theses

Mine waste rock is often recycled for paste and cement backfill in underground cut and fill mining operations. Aggregate in concrete and road surfacing material is another use if the mine waste does not contain deleterious materials that can degrade surface and ground water quality where it is used. Shotcrete usage in mining has been primarily limited to packaged dry mixes from offsite manufacturers. Substituting a manufacturer’s pre-mixed shotcrete with crushed and sized mine waste rock can reduce both the shotcrete cost and the environmental impact of waste disposal operations by reducing the required volume capacity and footprint size required …


Particle Tracking Of A Simulated Melt Pool Of Selective Laser Melting, Prakash Gautam Oct 2020

Particle Tracking Of A Simulated Melt Pool Of Selective Laser Melting, Prakash Gautam

Graduate Theses & Non-Theses

Metal additive manufacturing (AM) produces parts by addition as compared to subtraction of material. Selective laser melting (SLM) is an AM technique that prints objects layer-by-layer, selectively melting powders using a laser. The mechanical properties of SLM parts are affected by processing parameters and powder characteristics, both of which alter the molten melt pool flow field. Marangoni convection (M-flow) is a thermo-capillary mass transfer from a region of lower surface tension to a region of higher surface tension, referred to as a radially outward flow for SLM. However, in the presence of surface-active elements such as oxides and sulfides, the …


Effect Of Global Energy Density On Dynamic Strain Hardening Of Selective Laser Melted Alsi10mg, Md Salah Uddin Oct 2020

Effect Of Global Energy Density On Dynamic Strain Hardening Of Selective Laser Melted Alsi10mg, Md Salah Uddin

Graduate Theses & Non-Theses

The characteristics of strain hardening of selective laser melting (SLM) processed AlSi10Mg under dynamic impact was investigated. The dynamic impact at high strain rate loading conditions occurs in many engineering applications, such as collisions of flying objects on aircraft engine components like bird impact, vehicle collisions, and impacts occur in sports events like club impact on golf balls and helmet impact. Among these various applications, the strength of the materials needs to characterize accurately for product quality, performance, and reliability.

AlSi10Mg is a lightweight metal alloy, and it has a growing demand in aircraft, military, and automotive applications. SLM is …


Electric Drives With Wide Bandgap Devices For Two-Phase Very Low Inductance Machines, Yibin Zhang, Damien Lawhorn, Peng Han, Aaron M. Cramer, Dan M. Ionel Oct 2020

Electric Drives With Wide Bandgap Devices For Two-Phase Very Low Inductance Machines, Yibin Zhang, Damien Lawhorn, Peng Han, Aaron M. Cramer, Dan M. Ionel

Power and Energy Institute of Kentucky Faculty Publications

Slotless and coreless machines with low inductance and low core losses are attractive for high speed and high power density applications. With the increase in fundamental frequency, typical drive implementations using conventional silicon-based devices are performance limited and also produce large current and torque ripples. This paper presents a systematic study of proposed drive configurations implemented with wide bandgap (WBG) devices in order to mitigate such issues for 2-phase very low inductance machines. Two inverter topologies, i.e., a dual H-bridge inverter with maximum redundancy and survivability and a 3-leg inverter for reduced cost, are considered. Feasible modulation schemes are derived …


Using Schema Training To Facilitate Students' Understanding Of Challenging Engineering Concepts In Heat Transfer And Thermodynamics, Dazhi Yang, Ruth Streveler, Ronald L. Miller, Inanc Senocak, Jim Slotta Oct 2020

Using Schema Training To Facilitate Students' Understanding Of Challenging Engineering Concepts In Heat Transfer And Thermodynamics, Dazhi Yang, Ruth Streveler, Ronald L. Miller, Inanc Senocak, Jim Slotta

Educational Technology Faculty Publications and Presentations

Background: Chi and colleagues have argued that some of the most challenging engineering concepts exhibit properties of emergent systems. However, students often lack a mental framework, or schema, for understanding emergence. Slotta and Chi posited that helping students develop a schema for emergent systems, referred to as schema training, would increase the understanding of challenging concepts exhibiting emergent properties.

Purpose: We tested the effectiveness of schema training and explored the nature of challenging concepts from thermodynamics and heat transfer. We investigated if schema training could (a) repair misconceptions in advanced engineering students and (b) prevent them in beginning engineering students. …