Physical Sciences and Mathematics Commons^™

Predicting Pair Success In A Pair Programming Eye Tracking Experiment Using Cross-Recurrence Quantification Analysis, Maureen M. Villamor, Maria Mercedes T. Rodrigo

Department of Information Systems & Computer Science Faculty Publications

Pair programming is a model of collaborative learning. It has become a well-known pedagogical practice in teaching introductory programming courses because of its potential benefits to students. This study aims to investigate pair patterns in the context of pair program tracing and debugging to determine what characterizes collaboration and how these patterns relate to success, where success is measured in terms of performance task scores. This research used eye-tracking methodologies and techniques such as cross-recurrence quantification analysis. The potential indicators for pair success were used to create a model for predicting pair success. Findings suggest that it is possible to …

Construction Of A Repeatable Framework For Prostate Cancer Lesion Binary Semantic Segmentation Using Convolutional Neural Networks, Ian Vincent O. Mirasol, Patricia Angela R. Abu, Rosula Sj Reyes

Department of Information Systems & Computer Science Faculty Publications

Prostate cancer is the 3rd most diagnosed cancer overall. Current screening methods such as the prostate-specific antigen test could result in overdiagonosis and overtreatment while other methods such as a transrectal ultrasonography are invasive. Recent medical advancements have allowed the use of multiparametric MRI — a noninvasive and reliable screening process for prostate cancer. However, assessment would still vary from different professionals introducing subjectivity. While con-volutional neural network has been used in multiple studies to ob-jectively segment prostate lesions, due to the sensitivity of datasets and varying ground-truth established used in these studies, it is not possible to reproduce and …

The Uses Of A Dual-Band Corrugated Circularly Polarized Horn Antenna For 5g Systems, Chih-Kai Liu, Wei-Yuan Chiang, Pei-Zong Rao, Pei-Hsiu Hung, Shih-Hung Chen, Chiung-An Chen, Liang-Hung Wang, Patricia Angela R. Abu, Shih-Lun Chen

Department of Information Systems & Computer Science Faculty Publications

This paper presents the development of a wide-beam width, dual-band, omnidirectional antenna for the mm-wave band used in 5G communication systems for indoor coverage. The 5G indoor environment includes features of wide space and short range. Additionally, it needs to function well under a variety of circumstances in order to carry out its diverse set of network applications. The waveguide antenna has been designed to be small enough to meet the requirements of mm-wave band and utilizes a corrugated horn to produce a wide beam width. Additionally, it is small enough to integrate with 5G communication products and is easy …

How Can Microgrids Help The Philippines’ Energy Transition? Adapting The Institutional Analysis And Development (Iad) Framework For Microgrid Development, John Charles A. Altomonte, Hannah Sofia Guinto

Environmental Science Faculty Publications

The Philippine energy sector remains plagued with issues of energy security, high electricity costs, and vulnerable grid infrastructure. This paper argues for the increased uptake of microgrids as a solution for these issues, using the Institutional Analysis and Development (IAD) Framework as a guide for microgrid policy. We begin this paper with an analysis of existing energy policies in the Philippines, highlighting a lacking integrated approach for energy security. The main discussion explores the IAD framework for microgrid development in the Philippines, identifying key barriers and dynamics among institutions and actors in the local energy sector. We then conclude with …

Island Stories: Mapping The (Im)Mobility Trends Of Slow Onset Environmental Processes In Three Island Groups Of The Philippines, Sonja Ayeb-Karlsson, Noralene Uy

Environmental Science Faculty Publications

There is an immediate lack of people-centred empirical evidence investigating how slow onset events influence human (im)mobility across the globe. This represents an important knowledge gap that makes it difficult for climate policy to safeguard vulnerable populations (whether on the move or left behind). In this study, 48 qualitative focus group discussions in the Philippines elaborated around people’s (im)mobility pathways in the context of slow onset events. The selected collective storytelling approach effectively mapped out the (im)mobility trends of 12 different origin- and destination locations involving the perceptions of 414 women and men across six provinces on Luzon, the Visayas …

Representation Learning On Heterogeneous Spatiotemporal Networks, Dakshak Keerthi Chandra

Doctoral Dissertations

“The problem of learning latent representations of heterogeneous networks with spatial and temporal attributes has been gaining traction in recent years, given its myriad of real-world applications. Most systems with applications in the field of transportation, urban economics, medical information, online e-commerce, etc., handle big data that can be structured into Spatiotemporal Heterogeneous Networks (SHNs), thereby making efficient analysis of these networks extremely vital. In recent years, representation learning models have proven to be quite efficient in capturing effective lower-dimensional representations of data. But, capturing efficient representations of SHNs continues to pose a challenge for the following reasons: (i) Spatiotemporal …

Variational Data Assimilation For Two Interface Problems, Xuejian Li

Doctoral Dissertations

“Variational data assimilation (VDA) is a process that uses optimization techniques to determine an initial condition of a dynamical system such that its evolution best fits the observed data. In this dissertation, we develop and analyze the variational data assimilation method with finite element discretization for two interface problems, including the Parabolic Interface equation and the Stokes-Darcy equation with the Beavers-Joseph interface condition. By using Tikhonov regularization and formulating the VDA into an optimization problem, we establish the existence, uniqueness and stability of the optimal solution for each concerned case. Based on weak formulations of the Parabolic Interface equation and …

Analysis Of Bio-Alcohols With Mie-Scattering And Ltc For Lowered Emissions In Pcci, Cesar E. Carapia

Electronic Theses and Dissertations

An investigation was conducted on the optimal engine parameters for facilitating lower NOX and soot emissions of PCCI combustion with either ethanol or n-butanol. The PFI fuels selected were tested at loads of 3, 4, and 5 Bar IMEP for a total of 28 total combustion tests with variations made to the EGR% and boost pressure for each test in order to find the optimal emissions strategy. A Mie-scattering spray fuel analysis was also conducted on the three fuels to gain insight on their influence on combustion/emissions characteristics. It was found that ethanol had a greater average Sauter Mean Diameter …

Humanizing Computational Literature Analysis Through Art-Based Visualizations, Alexandria Leto

Electronic Theses and Dissertations

Inequalities in gender representation and characterization in fictional works are issues that have long been discussed by social scientists. This work addresses these inequalities with two interrelated components. First, it contributes a sentiment and word frequency analysis task focused on gender-specific nouns and pronouns in 15,000 fictional works taken from the online library, Project Gutenberg. This analysis allows for both quantifying and offering further insight on the nature of this disparity in gender representation. Then, the outcomes of the analysis are harnessed to explore novel data visualization formats using computational and studio art techniques. Our results call attention to the …

Correlations And Reuse For Fast And Accurate Physically Based Light Transport, Benedikt Bitterli

Dartmouth College Ph.D Dissertations

Light transport is the study of the transfer of light between emitters, surfaces, media and sensors. Fast simulations of light transport play a pivotal role in photo-realistic image synthesis, and find many applications today, including predictive manufacturing, machine learning, scientific visualization and the movie industry. In order to accurately reproduce the appearance of real scenes, light transport must closely approximate the physical laws governing the flow of light. Physically based rendering is a set of principles for codifying these laws into a mathematical model, and is the predominant rendering methodology today.

The representational power of this model is limited to …

Outsourcing Climate Change, Rui Dai, Rui Duan, Hao Liang, Lilian Ng

Research Collection Lee Kong Chian School Of Business

This paper examines whether and how firms combat climate change. Our study provides robust evidence that firms outsource part of their carbon emissions to foreign suppliers and shows how internal and external stakeholders significantly shape firms' environmental policies. Furthermore, firms tend to seek a foreign supplier and decrease their emission abatement efforts as pressure to reduce domestic emissions intensifies. These firms are also less incentivized to develop green technologies. Finally, we find that outsourcing emissions has real and economic consequences, with investors demanding a higher carbon premium for their exposures to carbon risks associated with increased outsourced emissions.

Drivers And Controls On Soil Carbon Storage In Temperate Forest Soils, Adam Noel

Graduate College Dissertations and Theses

Elevated atmospheric CO2 levels pose a threat the global climate stability but large amounts of carbon can be held within soils worldwide. Forests function to capture carbon and eventually, through litter inputs and decomposition, add this carbon to soil systems. This process is driven by climate, landscape conditions, forest and soil characteristics, that have complex interactions with one another across spatial scales. In this dissertation, I examine drivers of carbon contributions to the mineral soil, via litter decomposition and forest floor carbon pools, and how these contributions vary with forest composition and soil conditions. First, using data from a 10-year …

Characterizing Phosphorus Transport To Agricultural Tile Drains In Vermont, Ryan Andrew Ruggiero

Graduate College Dissertations and Theses

Dairy agroecosystems use subsurface or tile drainage to improve trafficability and crop yield. One of the main concerns of tile drainage is that it acts as a major source of non-point phosphorus (P) pollution because of preferential flow pathways (PFP). PFP are large conduits in the soil that allow rapid movement of water. This reduces contact time infiltrate has with deeper soil horizons, which are not saturated with P and that could act as a sink for this nutrient. Also, PFP are responsible for channeling manure applied at the surface to tile drains. The rate of tile drain installation is …

Constraint-Aware And Efficiency-Aware Control Of Air-Path In Fuel Cell Vehicles, Eli Bacher-Chong

Graduate College Dissertations and Theses

Fuel cell technology offers the potential for clean, efficient, robust energy productionfor both stationary and mobile applications. But without fast and robust control systems, fuel cells cannot hope to maintain real-life efficiencies near enough to their theoretical potential. This work studies control and constraint management techniques to regulate a nonlinear multivariable air-path system for a proton exchange membrane fuel cell (PEMFC). The control objectives are to avoid oxygen starvation, run at the maximum net efficiency, achieve fast tracking of air flow and pressure set-points, and be easy to calibrate. To operate at maximum efficiency, a set-point map is generated for …

Embracing Uncertainty, Ambiguity, And Complexity In Agriculture, Science, And Policy, Benjamin Timothy Dube

Graduate College Dissertations and Theses

Policy makers say they govern the environment based on scientific evidence, but environmental activists express concern about issues that challenge scientific understandings, such as risk, uncertainty, justice, and participation. This conflict is magnified in agriculture, where many social movements and farmers advocate and create farming systems that are ecological—diverse, heterogenous and adaptive. Ecological farming systems are thus harder for outside experts - researchers, extensionists, development practitioners or policymakers – to understand. Complexity and context-specificity in ecological agriculture presents numerous challenges along the path from scientific inquiry to policy implementation, including in categorizing, systematically studying, modelling and regulating farming systems. In …

Phosphorus Dynamics In Restored Riparian Wetlands On Former Agricultural Land In Vermont, Adrian Robert Hendrick Wiegman

Graduate College Dissertations and Theses

Wetland restoration has numerous potential ecological and societal benefits, one of which is the retention of phosphorus (P) and consequent protection of downstream water bodies from eutrophication. Past studies focused on influents to and effluents from a variety of wetland types have documented net P retention. However, some wetland systems are less effective at P capture and wetland P retention capacity can change over time. Certain wetland types - especially riparian wetlands restored on former agricultural land - remain understudied. In Vermont, most of the over 4000 potential wetland restoration sites in the Lake Champlain Basin are located on current …

Multi-Scale Assessment Of Gully Erosion At Road Drainage Outlets, Emma Louise Estabrook

Graduate College Dissertations and Theses

Gully erosion and sediment deposition from roads are underrated sources of sediments entering receiving waterways. While gully erosion has been studied throughout the world, the monitoring of the temporal and spatial erosional processes related to culverts and road drainage is rare. The objectives of this study are to quantify rates of gully erosion from Vermont’s transportation drainage networks at multiple temporal scales and report on insights gained from a multi-scale approach to monitoring gully erosion. To quantify event to seasonal timescales of gully erosion, high resolution terrestrial LiDAR surveys were conducted at 13 field sites. Field sites were monitored at …

Strain-Enhanced Coherent Exciton-Polaron States In 1d Phthalocyanine Crystalline Thin Films, Libin Liang

Graduate College Dissertations and Theses

Organic semiconductors are at the forefront of materials research, due to their desired electric and mechanical properties. They offer the unique opportunity to modify material properties during synthesis process, opening an avenue to the development of novel flexible and wearable electronic and photonic devices.Molecular excitons are of importance in organic semiconductor properties. While majority of research studies are centered on achieving good control of amorphous or polycrystalline thin film properties, the static disorder effect leads to poor device performance when compared to inorganic semiconductors with superior crystalline ordering. On the other hand, the macroscopic molecular long-range ordering can enhance device …

Tuning Electroluminescence From Resonators Based On Fabry-Pérot Microcavity Oleds, Ekraj Dahal

Graduate College Dissertations and Theses

This thesis comprises a series of methods for controlling the electroluminescence from Fabry-Pérot microcavity OLEDs by varying the resonator geometry and the location of the organic emitter within the resonator. In pursuit of this thesis, I conducted three experimental projects backed by theoretical modeling. First the thickness of the microcavity was varied to observe changes in resonant state wavelength, linewidth of the states, angular dispersion, and polarization splitting. The resulting electroluminescence can be tuned to span the entire color gamut using a single green chromophore. Electroluminescence of this green chromophore was used to pump the optical states of nominally identical …

Enhancing Cybersecurity Of Power Systems Using Machine Learning, Fayha Almutairy

Graduate College Dissertations and Theses

The continuous and accelerated digitalization of industries and technologies has made most of our daily activities obtrusively depend on electricity. Consequently, reliable power system operation became the cornerstone of economic sustainability and technological development. Unfortunately, the grown dependency of modern power infrastructure on Information and Communication Technology (ICT) has increased the risks of cyber-attacks. According to the most recent statistics, the electrical power sector is one of the significant fields in the number of cyber-attacks per year. The most devious types of cyber-attacks target the power system state estimation. Realtime state estimation aims to filter out the noise of measurements …

Hydroclimatic Variability Of The Northeastern United States, Caitlin Crossett

Graduate College Dissertations and Theses

Over the historical record, the climate of the Northeastern United States (hereafter Northeast) has moved in and out of periods of drought and pluvial conditions. Precipitation has increased drastically over the past three decades but, within the same time frame, the Northeast has also experienced several significant drought events. If we can more fully understand the processes and drivers behind extreme hydroclimatic events in the historical record we may be able to gain a better understanding of the dynamics of why things are changing, aiding not only in our interpretation of global climate models but in the processes themselves. A …

Assessing Assumptions And Applying Cosmogenic Nuclide Methods To Earth Surface Processes, Christopher T. Halsted

Graduate College Dissertations and Theses

Terrestrial in situ cosmogenic radionuclides are powerful tools for quantifying rates and durations of Earth surface processes. Among the many applications of cosmogenic radionuclides are quantification of basin-scale erosion rates, burial durations of paleosols and terrace sediments, and unraveling of glacial chronologies. In this dissertation I use large data sets to investigate methodological assumptions critical for using cosmogenic radionuclides to interpret Earth surface processes, and I apply this isotope system to reconstruct the deglacial history of the Laurentide Ice Sheet in the northeastern United States.

I use new and previously-published measurements of in situ 26Al and 10Be concentrations, over 300 …

On The Enhancement Of Penetrating Radar Target Location Accuracy With Visual-Inertial Slam, Joshua Girard

Graduate College Dissertations and Theses

This paper presents research concerning the use of visual-inertial Simultaneous Localization And Mapping (SLAM) algorithms to aid in Continuous Wave (CW) radar target mapping. SLAM is an established field in which radarhas been used to internally contribute to the localization algorithms. Instead, the application in this case is to use SLAM outputs to localize radar data and construct three-dimensional target maps which can be viewed in augmented reality. These methods are transferable to other types of radar units and sensors, but this paper presents the research showing how the methods can be applied to calculate depth efficiently with CW radar …

High-Resolution Downscaling And Bias-Correction Of Temperature And Precipitation: Advances In Statistical Methods, Maike Holthuijzen

Graduate College Dissertations and Theses

High-resolution, bias-corrected climate data is necessary for climate impact studies and modeling efforts at local scales. General circulation models (GCMs) provide important information about historical and future larger-scale climate trends, but their spatial resolution is too coarse to investigate localized effects of climate processes. Additionally, raw GCM output is characterized by some degree of bias. Two post-processing procedures known as downscaling and bias-correction are typically applied to raw climate model output prior to its use in further modeling applications. Downscaling is the process in which data at a coarse spatial scale is transformed to a fine spatial scale. Bias-correction refers …

Climate Adaptive Forest Management In The Northeastern Us: Social And Ecological Motivations, Barriers, And Responses Of Rural And Urban Foresters, Teresa Mcgann

Graduate College Dissertations and Theses

This project examines how foresters in a diversity of professional contexts perceive and respond to global change in the northeastern United States, with the goal of supporting foresters in broadening and deepening their use of climate adaptive strategies. Based on qualitative analysis of 32 in-depth semi-structured interviews with urban and rural foresters (n = 15 and n = 17, respectively) across New England and New York, a summary is presented of the i) important environmental drivers of adaptation; ii) commonly employed adaptive practices; iii) significant barriers to adaptation; and iv) approaches to working through named barriers. According to the motivations, …

Implications Of Population Genetics And Physiological Responses On The Conservation Of Moose (Alces Alces Americana), Elias Rosenblatt

Graduate College Dissertations and Theses

Wildlife populations around the globe are facing numerous, complex challengesto their persistence, yet conservation efforts are hindered by limited information about these populations and the anthropogenic pressures they face. North American moose (Alces alces americana), despite being of ecological, cultural, and economical importance, inhabit remote landscapes, making population monitoring difficult. At the same time, many moose populations, including in Vermont and eastern North America, have experienced recent declines mainly due to winter tick (Dermacentor albipictus) epizootics. Anthropogenic landscape change and climate-mediated pressures pose future challenges for moose across the southern extent of their distribution. Though impacts of winter tick infestation …

Management For Amphibians In Complex Ecosystems, Lindsey Pekurny

Graduate College Dissertations and Theses

Effective conservation is becoming more difficult as threats to wildlife increase. Natural resource managers are pressured to make difficult decisions with limited resources, and in many instances, some degree of uncertainty. Scientists and managers tasked with the conservation of a species need tools to help guide efficient decision making. Often, information for management decisions is insufficient. Tools that help to inform decision makers and address uncertainty will be invaluable to effective conservation initiatives. Here, we create two models to help managers navigate the complexities associated with decision making. The objective our first study was to create a model to best …

Elements Of Biocontrol Strategies For Pheretimoid Earthworms, Maryam Nouri-Aiin

Graduate College Dissertations and Theses

Jumping worms (Megascolecidae) in the pheretimoid complex, have raisedconsiderable environmental concerns with conservationists, ecologists, policy makers, and the public. Their impacts on North American forests and high density is distinct from earthworms in other families. Most of the infested forests are near horticultural settings. Practicable options to manage their dispersal into forests do not exist. This dissertation examines the potential of an entomopathogenic fungus to control them in horticulture. It also investigates major barriers to managing their spread and studying their ecology including species identification, phenology, and genetic diversity. First, to discover the best time to apply biocontrol agents, I …

Assessing Recovery And Reuse Of Nutrients Using Grid-Based Spatial Modeling: A Case Study Of Sri Lanka, Maya Fein-Cole

Graduate College Dissertations and Theses

Identifying and implementing strategies for recovering resources from waste streams for reuse helps to minimize natural resource extraction and reduces waste generation. Spatial modeling can guide resource cycling by optimizing co-location of recovery and reuse. These models can help assess feasibility and effectiveness (e.g., meeting crop nutrient needs) of circular economy practices at a landscape scale. Though many useful models exist, there is a need for an adaptable grid-based tool to address reuse on a per area basis (e.g., kg nitrogen per hectare of cropland). A model like this could be applied to any landscape and would utilize input data …

Leveraging Behavioral Data For Public Health: Exploring Sleep And Nature Exposure Using Mobile Phones And Social Media, Kelsey Linnell

Graduate College Dissertations and Theses

Health surveillance and assessment are considered essential components of a func- tional public health system. The recent ubiquity of mobile devices and social media have created a wealth of behavioral data, and bring into existence new forms of pop- ulation health monitoring. These new digital sources can provide direct and passive data for more detailed and nuanced health factors, and have expanded the human, spatial, and temporal scales at which these factors can be measured. In this project, I leverage digital trace data from tweets and mobile device location pings to explore population scale sleep loss, and nature exposure through …