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A Deterministic Model Of The Effect Of Electric Field On Chemotherapeutics Delivery Into A Tumor, Maryam Moarefian, Luke Achenie 2017 Virginia Polytechnic Institute and State University

A Deterministic Model Of The Effect Of Electric Field On Chemotherapeutics Delivery Into A Tumor, Maryam Moarefian, Luke Achenie

Biology and Medicine Through Mathematics Conference

No abstract provided.


An Improved Algorithm For Learning To Perform Exception-Tolerant Abduction, Mengxue Zhang 2017 Washington University in St. Louis

An Improved Algorithm For Learning To Perform Exception-Tolerant Abduction, Mengxue Zhang

Engineering and Applied Science Theses & Dissertations

Abstract

Inference from an observed or hypothesized condition to a plausible cause or explanation for this condition is known as abduction. For many tasks, the acquisition of the necessary knowledge by machine learning has been widely found to be highly effective. However, the semantics of learned knowledge are weaker than the usual classical semantics, and this necessitates new formulations of many tasks. We focus on a recently introduced formulation of the abductive inference task that is thus adapted to the semantics of machine learning. A key problem is that we cannot expect that our causes or explanations will be perfect ...


Acoustic Tweets And Blogs: Using Social Media In An Undergraduate Acoustics Course, Lily M. Wang 2017 University of Nebraska - Lincoln

Acoustic Tweets And Blogs: Using Social Media In An Undergraduate Acoustics Course, Lily M. Wang

Lily M Wang

Each fall, the author teaches an undergraduate architectural acoustics course to around 40 third-year architectural engineering students at the University of Nebraska. Beginning in 2011, a social media component was introduced to explore the use of this technology and how it may supplement the students' learning experience. Students were given an opportunity to receive extra credit by using Twitter and/or blogging about course material using a set hashtag (#AE3300) or through the course website. Results were positive, and the author will discuss pros and cons that she has experienced in adding this social media component. Suggestions for future implementations ...


A Need For Evidence-Based And Multidisciplinary Research To Study The Effects Of The Interaction Of School Environmental Conditions On Student Achievement, Josephine Lau, Lily M. Wang, Clarence Waters, James A. Bovaird 2017 University of Nebraska-Lincoln

A Need For Evidence-Based And Multidisciplinary Research To Study The Effects Of The Interaction Of School Environmental Conditions On Student Achievement, Josephine Lau, Lily M. Wang, Clarence Waters, James A. Bovaird

Lily M Wang

With funding from the U.S. Environmental Protection Agency’s (EPA) Healthy Schools initiative, a research team from the University of Nebraska– Lincoln (UNL) is currently working on establishing how environmental conditions in K-12 school buildings impact student scholastic achievement. The objectives of the research project are: (1) to study comprehensively the impacts of a wide set of indoor environmental factors (including indoor air quality, thermal, lighting and acoustic conditions) on student achievement; (2) to investigate how these environmental conditions interact with each other to impact student achievement; (3) to rank order the environmental variables in terms of their relative ...


Effects Of Reverberation And Noise On Speech Comprehension By Native And Non-Native English-Speaking Listeners, Z. Ellen Peng, Lily M. Wang, Siu-Kit Lau, Adam M. Steinbach 2017 University of Nebraska-Lincoln

Effects Of Reverberation And Noise On Speech Comprehension By Native And Non-Native English-Speaking Listeners, Z. Ellen Peng, Lily M. Wang, Siu-Kit Lau, Adam M. Steinbach

Lily M Wang

Previous studies have demonstrated the negative impact of adverse signal-to-noise-ratios on non-native English-speaking listeners' performance on speech recognition using recall tasks, as well as implied that comprehension skills were more impaired than recognition skills under reverberation and noise. The authors have themselves previously conducted a pilot study on three native and three non-native Englishspeaking listeners to examine the effects of reverberation and noise using speech comprehension tasks. Those results suggested that speech comprehension performance is worse under longer reverberation times (RT), and that a longer RT is more detrimental to speech comprehension by non-native listeners than native listeners. This paper ...


How Tonality And Loudness Of Noise Relate To Annoyance And Task Performance” Noise Control Eng. J. 65(2), 71-82., Joonhee Lee, Jennifer M. Francis, Lily M. Wang 2017 University of Nebraska - Lincoln

How Tonality And Loudness Of Noise Relate To Annoyance And Task Performance” Noise Control Eng. J. 65(2), 71-82., Joonhee Lee, Jennifer M. Francis, Lily M. Wang

Lily M Wang

Audible tones in noise generated by building mechanical equipment can be a leading cause of complaints from occupants. A number of metrics have been developed to quantify prominence of a tone, but previous work has shown that the impact of a certain tonality appears to vary with the level of the broadband noise signal. More work on how tonal signals of varying tonality, tone frequency and broadband noise levels relate to annoyance and task performance is needed. This paper investigates such relationships between current noise metrics, annoyance and task performance under assorted tonal noise conditions through subjective testing. Participants rated ...


Perception Of 3d Symmetrical And Near-Symmetrical Shapes, Vijai Jayadevan, Aaron Michaux, Edward Delp, Zygmunt Pizlo 2017 Purdue University

Perception Of 3d Symmetrical And Near-Symmetrical Shapes, Vijai Jayadevan, Aaron Michaux, Edward Delp, Zygmunt Pizlo

MODVIS Workshop

No abstract provided.


Design And Computational Fluid Dynamics Analysis Of An Idealized Modern Wingsuit, Maria E. Ferguson 2017 Washington University in St Louis

Design And Computational Fluid Dynamics Analysis Of An Idealized Modern Wingsuit, Maria E. Ferguson

Engineering and Applied Science Theses & Dissertations

The aerodynamics of a modern wingsuit has been the subject of very few detailed scientific studies to date. The prevailing design process remains the dangerous “sew and fly” method, in which designs are tested when they are first flown. This study utilizes Computational Fluid Dynamics (CFD) tools to analyze the flow field and aerodynamics of an idealized wingsuit, which is designed using Computer-Aided Design (CAD) modeling. The 3D CAD software Autodesk Inventor is used to create the wingsuit model, which is designed with a Gottingen 228 airfoil cross-section and a relatively large planform of aspect ratio 1.3. The commercial ...


The Impact Of The Mitochondrial Metabolism Of Induced Pluripotent Stem Cells Upon Differentiation, Stefanie T. Shahan 2017 Washington University

The Impact Of The Mitochondrial Metabolism Of Induced Pluripotent Stem Cells Upon Differentiation, Stefanie T. Shahan

Engineering and Applied Science Theses & Dissertations

Induced pluripotent stem cells (iPSCs) can be differentiated into any cell type found in the body. The derivation of a stem cell derived β cell (SC-β) capable of responding to glucose by secreting insulin was hugely significant for diabetes research and opened up the possibility of cell replacement therapy to combat this widespread disease (Pagliuca et al. 2014). The optimization of differentiation procedures such as this could improve yield, function, cost, and efficiency of a stem cell-derived product. Current approaches to improve differentiation are primarily focused on signal transduction pathways, while the metabolic state of the cells has received little ...


Uncertainty Quantification Of Turbulence Model Closure Coefficients In Openfoam And Fluent For Mildly Separated Flows, Ike Witte 2017 Washington University in St Louis

Uncertainty Quantification Of Turbulence Model Closure Coefficients In Openfoam And Fluent For Mildly Separated Flows, Ike Witte

Engineering and Applied Science Theses & Dissertations

In this thesis, detailed uncertainty quantification studies focusing on the closure coefficients of eddy-viscosity turbulence models for several flows using two CFD solvers have been performed. Three eddy viscosity turbulence models considered are: the one-equation Spalart-Allmaras (SA) model, the two-equation Shear Stress Transport (SST) k-ω model, and the one-equation Wray-Agarwal (WA) model. OpenFOAM and ANSYS Fluent are used as flow solvers. Uncertainty quantification analyses are performed for subsonic flow over a flat plate, subsonic flow over a backward-facing step, and transonic flow past an axisymmetric bump. In the case of flat plate, coefficients of pressure, lift, drag, and skin friction ...


Utilizing High Resolution Bus Gps Data To Visualize And Identify Congestion Hot-Spots In Urban, Nicholas B. Stoll, Travis B. Glick, Miguel Figliozzi 2017 Portland State University

Utilizing High Resolution Bus Gps Data To Visualize And Identify Congestion Hot-Spots In Urban, Nicholas B. Stoll, Travis B. Glick, Miguel Figliozzi

Miguel A. Figliozzi

Congestion and travel delay on urban roadways can influence the roadways’ operating costs and service attractiveness. This research used high-resolution bus data to examine sources of delay on urban arterials. A set of tools was created to help visualize trends in bus behavior and movement; these tools allowed larger traffic trends to be visualized along urban corridors and streets. With buses as probes and examining aggregated bus behavior, contoured speed plots were used to understand the behavior of roadways outside the zone of influence of bus stops. Speed plots were used to discover trends and travel patterns with only a ...


A Conceptual Framework For Understanding Latent Demand: Accounting For Unrealized Activities And Travel, Kelly Clifton 2017 Portland State University

A Conceptual Framework For Understanding Latent Demand: Accounting For Unrealized Activities And Travel, Kelly Clifton

Kelly Clifton

Latent demand—the activities and travel that are desired but unrealized because of constraints—have been historically examined from the standpoint of understanding the impacts of proposed capacity or service improvements on travel demand.

Drawing on work from a variety of theoretical perspectives, this paper presents a broader conceptual view of latent demand that provides a useful framework for researching and understanding these unmet needs. This is important from an equity standpoint, as it provides insights into to questions of transport disadvantage, social exclusion and poverty.

The framework presented here is theoretical in nature and untested empirically. This study aims ...


Real Time Learning Level Assessment Using Eye Tracking, Saurin S. Parikh, Hari Kalva 2017 Florida Atlantic University

Real Time Learning Level Assessment Using Eye Tracking, Saurin S. Parikh, Hari Kalva

MODVIS Workshop

E-Learning is emerging as a convenient and effective learning tool. However, the challenge with eLearning is the lack of effective tools to assess levels of learning. Ability to predict difficult content in real time enables eLearning systems to dynamically provide supplementary content to meet learners’ needs. Recent developments have made possible low-cost eye trackers, which enables a new class of applications based on eye response. In comparison to past attempts using bio-metrics in learning assessments, with eye tracking, we can have access to the exact stimulus that is causing the response. A key aspect of the proposed approach is the ...


A Time-Series Forecasting Model For Windhoek Rainfall, Namibia, Godfrey T. Pazvakawambwa 2017 University of Namibia, Faculty of Engineering and IT

A Time-Series Forecasting Model For Windhoek Rainfall, Namibia, Godfrey T. Pazvakawambwa

Andrews Research Conference

The objective of the study was to use time series forecasting techniques to model Windhoek rainfall based on secondary monthly data from 1891 to 2011. Descriptive summary statistics in the form of measures of centrality and dispersion, time series plots, and autocorrelation functions were generated using R time series statistical software. The Box Jenkin’s ARIMA modelling procedure (model identification, model estimation, model validation) was used to determine the best models for the data. Model diagnostics based on residual analysis were performed to assess the adequacy of the identified models. The final model was then used to forecast monthly rainfall ...


Modeling Accommodation Control Of The Human Eye: Chromatic Aberration And Color Opponency, Agostino Gibaldi, Steven A. Cholewiak, Marty S. Banks 2017 University of California - Berkeley

Modeling Accommodation Control Of The Human Eye: Chromatic Aberration And Color Opponency, Agostino Gibaldi, Steven A. Cholewiak, Marty S. Banks

MODVIS Workshop

Accommodation is the process by which the eye lens changes optical power to maintain a clear retinal image as the distance to the fixated object varies. Although luminance blur has long been considered the driving feature for accommodation, it is by definition unsigned (i.e., there is no difference between the defocus of an object closer or farther than the focus distance). Nonetheless, the visual system initially accommodates in the correct direction, implying that it exploits a cue with sign information. Here, we present a model of accommodation control based on such a cue: Longitudinal Chromatic Aberration (LCA). The model ...


Color Algebras, Jeffrey B. Mulligan 2017 NASA Ames Research Center

Color Algebras, Jeffrey B. Mulligan

MODVIS Workshop

No abstract provided.


Open-Source Photometric System For Enzymatic Nitrate Quantification, Ben T. Wittbrodt, D. A. Squires, J. Walbeck, E. Campbell, W. H. Campbell, Joshua M. Pearce 2017 Michigan Technological University

Open-Source Photometric System For Enzymatic Nitrate Quantification, Ben T. Wittbrodt, D. A. Squires, J. Walbeck, E. Campbell, W. H. Campbell, Joshua M. Pearce

Joshua M. Pearce

Nitrate, the most oxidized form of nitrogen, is regulated to protect people and animals from harmful levels as there is a large over abundance due to anthropogenic factors. Widespread field testing for nitrate could begin to address the nitrate pollution problem, however, the Cadmium Reduction Method, the leading certified method to detect and quantify nitrate, demands the use of a toxic heavy metal. An alternative, the recently proposed Environmental Protection Agency Nitrate Reductase Nitrate-Nitrogen Analysis Method, eliminates this problem but requires an expensive proprietary spectrophotometer. The development of an inexpensive portable, handheld photometer will greatly expedite field nitrate analysis to ...


Low-Cost Open-Source Voltage And Current Monitor For Gas Metal Arc Weld 3d Printing, Anthony Pinar, Bas Wijnen, Gerald C. Anzalone, Timothy C. Havens, Paul G. Sanders, Joshua M. Pearce 2017 Michigan Technological University

Low-Cost Open-Source Voltage And Current Monitor For Gas Metal Arc Weld 3d Printing, Anthony Pinar, Bas Wijnen, Gerald C. Anzalone, Timothy C. Havens, Paul G. Sanders, Joshua M. Pearce

Joshua M. Pearce

Arduino open-source microcontrollers are well known in sensor applications for scientific equipment and for controlling RepRap 3D printers. Recently low-cost open-source gas metal arc weld (GMAW) RepRap 3D printers have been developed. The entry-level welders used have minimal controls and therefore lack any real-time measurement of welder voltage or current. The preliminary work on process optimization of GMAW 3D printers requires a low-cost sensor and data logger system to measure welder current and voltage. This paper reports on the development of a low-cost open-source power measurement sensor system based on Arduino architecture. The sensor system was designed, built, and tested ...


Exchanging Ohmic Losses In Metamaterial Absorbers With Useful Optical Absorption For Photovoltaics, Ankit Vora, Jephias Gwamuri, Nezih Pala, Anand Kulkarni, Joshua M. Pearce, Durdu Ö. Güney 2017 Michigan Technological University

Exchanging Ohmic Losses In Metamaterial Absorbers With Useful Optical Absorption For Photovoltaics, Ankit Vora, Jephias Gwamuri, Nezih Pala, Anand Kulkarni, Joshua M. Pearce, Durdu Ö. Güney

Joshua M. Pearce

Using metamaterial absorbers, we have shown that metallic layers in the absorbers do not necessarily constitute undesired resistive heating problem for photovoltaics. Tailoring the geometric skin depth of metals and employing the natural bulk absorbance characteristics of the semiconductors in those absorbers can enable the exchange of undesired resistive losses with the useful optical absorbance in the active semiconductors. Thus, Ohmic loss dominated metamaterial absorbers can be converted into photovoltaic near-perfect absorbers with the advantage of harvesting the full potential of light management offered by the metamaterial absorbers. Based on experimental permittivity data for indium gallium nitride, we have shown ...


Influence Of Oxygen Concentration On The Performance Of Ultra-Thin Rf Magnetron Sputter Deposited Indium Tin Oxide Films As A Top Electrode For Photovoltaic Devices, Jephias Gwamuri, Murugesan Marikkannan, J. Mayandi, Patrick Bowen, Joshua M. Pearce 2017 Michigan Technological University

Influence Of Oxygen Concentration On The Performance Of Ultra-Thin Rf Magnetron Sputter Deposited Indium Tin Oxide Films As A Top Electrode For Photovoltaic Devices, Jephias Gwamuri, Murugesan Marikkannan, J. Mayandi, Patrick Bowen, Joshua M. Pearce

Joshua M. Pearce

The opportunity for substantial efficiency enhancements of thin film hydrogenated amorphous silicon (a-Si:H) solar photovoltaic (PV) cells using plasmonic absorbers requires ultra-thin transparent conducting oxide top electrodes with low resistivity and high transmittances in the visible range of the electromagnetic spectrum. Fabricating ultra-thin indium tin oxide (ITO) films (sub-50 nm) using conventional methods has presented a number of challenges; however, a novel method involving chemical shaving of thicker (greater than 80 nm) RF sputter deposited high-quality ITO films has been demonstrated. This study investigates the effect of oxygen concentration on the etch rates of RF sputter deposited ITO films ...


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