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2021

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Predicting Prognosis And Idh Mutation Status For Patients With Lower-Grade Gliomas Using Whole Slide Images, Shuai Jiang, George J. Zanazzi, Saeed Hassanpour Dec 2021

Predicting Prognosis And Idh Mutation Status For Patients With Lower-Grade Gliomas Using Whole Slide Images, Shuai Jiang, George J. Zanazzi, Saeed Hassanpour

Dartmouth Scholarship

We developed end-to-end deep learning models using whole slide images of adults diagnosed with diffusely infiltrating, World Health Organization (WHO) grade 2 gliomas to predict prognosis and the mutation status of a somatic biomarker, isocitrate dehydrogenase (IDH) 1/2. The models, which utilize ResNet-18 as a backbone, were developed and validated on 296 patients from The Cancer Genome Atlas (TCGA) database. To account for the small sample size, repeated random train/test splits were performed for hyperparameter tuning, and the out-of-sample predictions were pooled for evaluation. Our models achieved a concordance- (C-) index of 0.715 (95% CI: 0.569, 0.830) for predicting prognosis …


Genomic Epidemiology Of Methicillin-Resistant And -Susceptible Staphylococcus Aureus From Bloodstream Infections, Joshua T. Smith, Elissa M. Eckhardt, Nicole B. Hansel, Tahmineh Rahmani Eliato, Isabella W. Martin, Cheryl P. Andam Dec 2021

Genomic Epidemiology Of Methicillin-Resistant And -Susceptible Staphylococcus Aureus From Bloodstream Infections, Joshua T. Smith, Elissa M. Eckhardt, Nicole B. Hansel, Tahmineh Rahmani Eliato, Isabella W. Martin, Cheryl P. Andam

Dartmouth Scholarship

Background: Bloodstream infections due to Staphylococcus aureus cause significant patient morbidity and mortality worldwide. Of major concern is the emergence and spread of methicillin-resistant S. aureus (MRSA) in bloodstream infections, which are associated with therapeutic failure and increased mortality. Methods: We generated high quality draft genomes from 323 S. aureus blood culture isolates from patients diagnosed with bloodstream infection at the Dartmouth-Hitchcock Medical Center, New Hampshire, USA in 2010–2018. Results: In silico detection of antimicrobial resistance genes revealed that 133/323 isolates (41.18%) carry horizontally acquired genes conferring resistance to at least three antimicrobial classes, with resistance determinants for aminoglycosides, beta-lactams …


A Network Linking Scene Perception And Spatial Memory Systems In Posterior Cerebral Cortex, Adam Steel, Madeleine M. Billings, Edward H. Silson, Caroline E. Robertson Dec 2021

A Network Linking Scene Perception And Spatial Memory Systems In Posterior Cerebral Cortex, Adam Steel, Madeleine M. Billings, Edward H. Silson, Caroline E. Robertson

Dartmouth Scholarship

The neural systems supporting scene-perception and spatial-memory systems of the human brain are well-described. But how do these neural systems interact? Here, using fine-grained individual-subject fMRI, we report three cortical areas of the human brain, each lying immediately anterior to a region of the scene perception network in posterior cerebral cortex, that selectively activate when recalling familiar real-world locations. Despite their close proximity to the scene-perception areas, network analyses show that these regions constitute a distinct functional network that interfaces with spatial memory systems during naturalistic scene understanding. These “place-memory areas” offer a new framework for understanding how the brain …


Efficiency Stagnation In Global Steel Production Urges Joint Supply- And Demand-Side Mitigation Efforts, Peng Wang, Morten Ryberg, Yi Yang, Kuishuang Feng, Sami Kara, Michael Hauschild, Wei Qiang Chen Dec 2021

Efficiency Stagnation In Global Steel Production Urges Joint Supply- And Demand-Side Mitigation Efforts, Peng Wang, Morten Ryberg, Yi Yang, Kuishuang Feng, Sami Kara, Michael Hauschild, Wei Qiang Chen

Dartmouth Scholarship

Steel production is a difficult-to-mitigate sector that challenges climate mitigation commitments. Efforts for future decarbonization can benefit from understanding its progress to date. Here we report on greenhouse gas emissions from global steel production over the past century (1900-2015) by combining material flow analysis and life cycle assessment. We find that ~45 Gt steel was produced in this period leading to emissions of ~147 Gt CO2-eq. Significant improvement in process efficiency (~67%) was achieved, but was offset by a 44-fold increase in annual steel production, resulting in a 17-fold net increase in annual emissions. Despite some regional technical improvements, the …


Estimating And Modeling Transpiration Of A Mountain Meadow Encroached By Conifers Using Sap Flow Measurements, Simon Joseph Marks Dec 2021

Estimating And Modeling Transpiration Of A Mountain Meadow Encroached By Conifers Using Sap Flow Measurements, Simon Joseph Marks

Master's Theses

Mountain meadows in the western USA are experiencing increased rates of conifer encroachment due to climate change and land management practices. Past research has focused on conifer removal as a meadow restoration strategy, but there has been limited work on conifer transpiration in a pre-restoration state. Meadow restoration by conifer removal has the primary goal of recovering sufficient growing season soil moisture necessary for endemic, herbaceous meadow vegetation. Therefore, conifer water use represents an important hydrologic output toward evaluating the efficacy of this active management approach. This study quantified and evaluated transpiration of encroached conifers in a mountain meadow using …


The Brown Bear Gut Microbiome: A Novel Tool For Conservation & Management, Sarah M. Trujillo Dec 2021

The Brown Bear Gut Microbiome: A Novel Tool For Conservation & Management, Sarah M. Trujillo

All NMU Master's Theses

Gut microbiomes (GMBs), complex communities of microorganisms inhabiting the gastrointestinal tracts of their hosts, perform countless micro-ecosystem services such as facilitating energy uptake and modulating immune responses. While scientists increasingly recognize the role GMBs play in host health, the role of GMBs in wildlife ecology and conservation has yet to be realized fully. Here, I use brown bears (Ursus arctos) as an ecological model to investigate (1) how both extrinsic and intrinsic factors influence GMB community membership and structure; and (2) the correlation between GMB membership and brown bear health metrics. To achieve these aims, I subsampled archived …


Trophic Ecology Of Juvenile Lean And Siscowet Lake Trout (Salvelinus Namaychush) From U.S. Waters Of Lake Superior, Will Otte Dec 2021

Trophic Ecology Of Juvenile Lean And Siscowet Lake Trout (Salvelinus Namaychush) From U.S. Waters Of Lake Superior, Will Otte

All NMU Master's Theses

In this study, I investigated the spatial overlap, diet similarity, and isotopic niches of juvenile Lean and Siscowet Lake Trout ecotypes across six ecoregions of Lake Superior. Spatially, Lean and Siscowet were observed in overlapping depth distributions. Leans were most abundant in shallow waters (60m). The greatest levels of cohabitation were observed in waters from 40-60m. Trophic position (as measured by δ 15N) was similar for both ecotypes at small sizes (mm), but Siscowet exhibited a higher trophic position than Lean Lake Trout at larger sizes (>400mm) and older ages (>5 years). Base of production (as measured by …


Evaluating The Undesired Outcomes Of Response Interruption And Redirection, Nicole Lafoille Dec 2021

Evaluating The Undesired Outcomes Of Response Interruption And Redirection, Nicole Lafoille

All NMU Master's Theses

Stereotypy is commonly defined as “frequent repetition of the same, typically purposeless movements, gestures, vocal sounds or utterances”, (Merriam-Webster Collegiate Dictionary, n.d.) and is a common perseverative behavior that is observed among children with autism spectrum disorder and other developmental disabilities. Stereotypy may result in interference with educational and therapeutic activities for the child. The present study sought to determine if the punishment procedure, response interruption and redirection (RIRD), is effective in reducing stereotypy during natural environment training without demonstrating other undesired behaviors that are associated with punishment procedures, including aggression, avoidance of staff, etc. Results of this study indicated …


Caregivers’ Understanding Of Early Literature Expectations For Firstborn Children Entering Kindergarten, Kathleen England Dec 2021

Caregivers’ Understanding Of Early Literature Expectations For Firstborn Children Entering Kindergarten, Kathleen England

All NMU Master's Theses

This qualitative phenomenological research was designed to develop an understanding of caregivers’ understanding of early literacy expectations for their firstborn or only child as they begin their kindergarten schooling. This study consisted of seven participants and six interviews with caregivers that enrolled their children in the Archdiocese of Detroit Catholic Schools in Southeast, MI. With the findings of this study, school administrators and researchers alike may be able to find a deeper understanding in efforts to support their families as they begin their educational careers and establish a solid foundation for further growth and development.


Reflections On Award-Winning Books, 1985-2020 Dec 2021

Reflections On Award-Winning Books, 1985-2020

The Writing Center Journal

Deidra Faye Jackson and Alice Johnston Myatt

Reflection: ESL Writers: A Guide for Writing Center Tutors

edited by Shanti Bruce and Ben Rafoth, 2004


The Effects Of Energy Intake On Upper Respiratory Symptoms In Ultra-Endurance Triathletes, Yasuki Sekiguchi, Deanna M. Dempsey, Rebecca L. Stearns, Jun Hashiwaki, Robert A. Huggins, Laura J. Kunces, J. Luke Pryor, Riana R. Pryor, Brittanie M. Volk, Jenna M. Bartley, Douglas J. Casa Dec 2021

The Effects Of Energy Intake On Upper Respiratory Symptoms In Ultra-Endurance Triathletes, Yasuki Sekiguchi, Deanna M. Dempsey, Rebecca L. Stearns, Jun Hashiwaki, Robert A. Huggins, Laura J. Kunces, J. Luke Pryor, Riana R. Pryor, Brittanie M. Volk, Jenna M. Bartley, Douglas J. Casa

Journal of Human Performance in Extreme Environments

Background: It is unclear whether energy intake can impact the incidence of upper respiratory symptoms (URS). The purpose of this study was to examine if there are differences in energy intake between symptomatic (SYM) and asymptomatic (ASYM) groups of URS in Ironman-triathletes. Methods: Thirty-three subjects competing in the Lake Placid Ironman-triathlon (mean±SD; age,37±8y; height,178±8cm; mass,76.3±10.4kg; body fat,10.8±3.8%) were randomized into either the control (CON) or intervention (INT). INT consumed 4-commercial recovery drinks, two immediately post-race and two 3-hours post-race. Calorie and macronutrient intake were recorded pre-, during, and post-race. Subjects completed the Wisconsin URS Survey to assess URS over the …


Review: Theories And Methods Of Writing Center Research: A Practical Guide Edited By Jo Mackiewicz And Rebecca Day Babcock, Emily Bouza Dec 2021

Review: Theories And Methods Of Writing Center Research: A Practical Guide Edited By Jo Mackiewicz And Rebecca Day Babcock, Emily Bouza

The Writing Center Journal

With nine chapters on theories and 10 chapters on methods, all contributed by knowledgeable professionals, Theories and Methods of Writing Center Research: A Practical Guide, edited by Jo Mackiewicz & Rebecca Day Babcock, is the research guide I have been waiting for. I have previously conducted two IRB-approved studies on writing centers and am in the middle of my third; without this guide, I have had to pull from multiple sources and have tried to read between the lines of published articles to determine the theories, methods, and methodologies that might best suit a writing center-specific context as a …


Post-Processing And Characterization Of Additive Manufactured Carbon Fiber Reinforced Semi-Crystalline Polymers, Patricia Revolinsky Dec 2021

Post-Processing And Characterization Of Additive Manufactured Carbon Fiber Reinforced Semi-Crystalline Polymers, Patricia Revolinsky

Mechanical & Aerospace Engineering Theses & Dissertations

The aim of this work is to study the effect of post-processing on additive manufactured (AM) continuous carbon fiber reinforced plastics (CFRPs) performance. As-printed AM CFRPs do not perform as well as conventionally manufactured CFRPs with the same composition. Possible improvements to AM CFRP performance include annealing and applying uniaxial pressure with elevated temperature. Samples were subjected to pressure and temperature treatments and annealing at a constant temperature. Treated materials were subjected to three-point bending tests, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM) to characterize and assess sample performance. Results were assessed for flexural strength, …


Oxytocin Attenuates The Stress-Induced Reinstatement Of Alcohol-Seeking In Male Rats: Role Of The Central Amygdala, Hannah S. Ballas, Samantha M. Wilfur, Nicole A. Freker, Kah-Chung Leong Dec 2021

Oxytocin Attenuates The Stress-Induced Reinstatement Of Alcohol-Seeking In Male Rats: Role Of The Central Amygdala, Hannah S. Ballas, Samantha M. Wilfur, Nicole A. Freker, Kah-Chung Leong

Psychology Faculty Research

Factors such as stress and anxiety often contribute to alcohol-dependent behavior and can trigger a relapse of alcohol addiction and use. Therefore, it is important to investigate potential pharmacological interventions that may alleviate the influence of stress on addiction-related behaviors. Previous studies have demonstrated that the neuropeptide oxytocin has promising anxiolytic potential in mammals and may offer a pharmacological target to diminish the emotional impact on reinstatement of alcohol-seeking. The purpose of the present study was to investigate the effect of oxytocin on stress-induced alcohol relapse and identify a neural structure mediating this effect through the use of an ethanol …


Mindful Wandering: Nature And Global Travel Through The Eyes Of A Farmgirl Scientist, Rebecca J. Romsdahl Dec 2021

Mindful Wandering: Nature And Global Travel Through The Eyes Of A Farmgirl Scientist, Rebecca J. Romsdahl

Digital Press Books

Mindful Wandering is an inspiring blend of memoir, travelogue, and environmental manifesto. As a translational ecologist, Rebecca Romsdahl is trained to ask critical questions about how we can improve our human relationships with the natural world for a sustainable, resilient future. As a farmgirl, she learned how to observe nature and life through the changing seasons. In this collection of essays spanning two decades, Romsdahl weaves these ideas together as she travels our changing world. From a Minnesota farm to the mountains of Peru and the edge of the Sahara Desert, she explores strategies for sustainability and resilience, and advocates …


The Wrong Side Of The Wall, Grant Mcmillan Dec 2021

The Wrong Side Of The Wall, Grant Mcmillan

Greenway Press Chapbooks

No abstract provided.


Modeling The Spatial Distribution Of The Current And Future Ecosystem Services Of Urban Tree Planting In Chicopee And Fall River, Massachusetts, R. Moody, N. Geron, M. Healy, J. Rogan, Deborah Martin Dec 2021

Modeling The Spatial Distribution Of The Current And Future Ecosystem Services Of Urban Tree Planting In Chicopee And Fall River, Massachusetts, R. Moody, N. Geron, M. Healy, J. Rogan, Deborah Martin

Geography

Mature urban tree canopy cover disrupts the local effects of urban heat islands and provides important ecosystem services such as energy savings through evaporation and shading, pollution removal, storm runoff control, and carbon sequestration. Sustainable urban tree canopy relies on the planting of juvenile trees. Typically, tree planting programs are only evaluated by the number of trees planted and there is a lack of analysis of juvenile trees post-planting. This study examines the value and distribution of energy savings provided by juvenile trees and how that value changes considering predicted tree growth and mortality by 2050. Using i-Tree Eco software, …


The Disrupt: A Measure Of Parent Distraction With Phones And Mobile Devices And Associations With Depression, Stress, And Parenting Quality., Brandon T. Mcdaniel Phd Dec 2021

The Disrupt: A Measure Of Parent Distraction With Phones And Mobile Devices And Associations With Depression, Stress, And Parenting Quality., Brandon T. Mcdaniel Phd

Health Services and Informatics Research

Abstract

The landscape of modern parenting has shifted as an increasing number of parents have and utilize smartphones and other mobile devices throughout the day. A validated measure of parent distraction with these devices is needed in the field. It is important to have a validated measure of parent distraction with mobile devices (e.g., phubbing, technoference), as this distraction can be common at times and could negatively impact the quality of parenting that children receive. In the current study, I developed a brief, parent-reported survey measure of parent distraction (DISRUPT), examined its reliability and validity (convergent, divergent) in two survey …


Graph Learning Assisted Multi-Objective Integer Programming, Yaoxin Wu, Wen Song, Zhiguang Cao, Jie Zhang, Abhishek Gupta, Mingyan Simon Lin Dec 2021

Graph Learning Assisted Multi-Objective Integer Programming, Yaoxin Wu, Wen Song, Zhiguang Cao, Jie Zhang, Abhishek Gupta, Mingyan Simon Lin

Research Collection School Of Computing and Information Systems

Objective-space decomposition algorithms (ODAs) are widely studied for solvingmulti-objective integer programs. However, they often encounter difficulties inhandling scalarized problems, which could cause infeasibility or repetitive nondominatedpoints and thus induce redundant runtime. To mitigate the issue, we presenta graph neural network (GNN) based method to learn the reduction rule in the ODA.We formulate the algorithmic procedure of generic ODAs as a Markov decisionprocess, and parameterize the policy (reduction rule) with a novel two-stage GNNto fuse information from variables, constraints and especially objectives for betterstate representation. We train our model with imitation learning and deploy it ona state-of-the-art ODA. Results show that …


Concise Mercurial Subvector Commitments: Definitions And Constructions, Yannan Li, Willy Susilo, Guomin Yang, Tran Viet Xuan Phuong, Yong Yu, Dongxi Liu Dec 2021

Concise Mercurial Subvector Commitments: Definitions And Constructions, Yannan Li, Willy Susilo, Guomin Yang, Tran Viet Xuan Phuong, Yong Yu, Dongxi Liu

Research Collection School Of Computing and Information Systems

Vector commitment and its variants have attracted a lot of attention recently as they have been exposed to a wide range of applications in blockchain. Two special extensions of vector commitments, namely subvector commitments and mercurial commitments, have been proposed with attractive features that are desirable in many applications. Nevertheless, to the best of our knowledge, a single construction satisfying all those attractive features is still missing. In this work, we analyze those important properties and propose a new primitive called mercurial subvector commitments, which are efficiently updatable, mercurial hiding, position binding, and aggregatable. We formalize the system model and …


Broadcast Authenticated Encryption With Keyword Search, Xueqiao Liu, Kai He, Guomin Yang, Willy Susilo, Joseph Tonien, Qiong Huang Dec 2021

Broadcast Authenticated Encryption With Keyword Search, Xueqiao Liu, Kai He, Guomin Yang, Willy Susilo, Joseph Tonien, Qiong Huang

Research Collection School Of Computing and Information Systems

The emergence of public-key encryption with keyword search (PEKS) has provided an elegant approach to enable keyword search over encrypted content. Due to its high computational complexity proportional to the number of intended receivers, the trivial way of deploying PEKS for data sharing with multiple receivers is impractical, which motivates the development of a new PEKS framework for broadcast mode. However, existing works suffer from either the vulnerability to keyword guessing attacks (KGA) or high computation and communication complexity. In this work, a new primitive for keyword search in broadcast mode, named broadcast authenticated encryption with keyword search (BAEKS), is …


Microservices Orchestration Vs. Choreography: A Decision Framework, Alan @ Ali Madjelisi Megargel, Christopher M. Poskitt, Shankararaman, Venky Dec 2021

Microservices Orchestration Vs. Choreography: A Decision Framework, Alan @ Ali Madjelisi Megargel, Christopher M. Poskitt, Shankararaman, Venky

Research Collection School Of Computing and Information Systems

Microservices-based applications consist of loosely coupled, independently deployable services that encapsulate units of functionality. To implement larger application processes, these microservices must communicate and collaborate. Typically, this follows one of two patterns: (1) choreography, in which communication is done via asynchronous message-passing; or (2) orchestration, in which a controller is used to synchronously manage the process flow. Choosing the right pattern requires the resolution of some trade-offs concerning coupling, chattiness, visibility, and design. To address this problem, we propose a decision framework for microservices collaboration patterns that helps solution architects to crystallize their goals, compare the key factors, and then …


Degree Doesn't Matter: Identifying The Drivers Of Interaction In Software Development Ecosystem, Amrita Bhattacharjee, Subhajit Datta, Subhashis Majumder Dec 2021

Degree Doesn't Matter: Identifying The Drivers Of Interaction In Software Development Ecosystem, Amrita Bhattacharjee, Subhajit Datta, Subhashis Majumder

Research Collection School Of Computing and Information Systems

Large scale software development ecosystems represent one of the most complex human enterprises. In such settings, developers are embedded in a web of shared concerns, responsibilities, and objectives at individual and collective levels. A deep understanding of the factors that influence developers to connect with one another is crucial in appreciating the challenges of such ecosystems as well as formulating strategies to overcome those challenges. We use real world data from multiple software development ecosystems to construct developer interaction networks and examine the mechanisms of such network formation using statistical models to identify developer attributes that have maximal influence on …


Channel Integration Services In Online Healthcare Communities, Anqi Zhao, Qian Tang Dec 2021

Channel Integration Services In Online Healthcare Communities, Anqi Zhao, Qian Tang

Research Collection School Of Computing and Information Systems

In online healthcare communities, channel integration services have become the bridge between online and offline channels, enabling patients to easily migrate across channels. Different from pure online services, online-to-offline (On2Off) and offline-to-online (Off2On) channel integration services involve both channels. This study examines the interrelationships between pure online services and channel integration services. Using a panel dataset composed of data from an online healthcare community, we find that pure online services decrease patients’ demand for On2Off integration services but increase their use of Off2On integration services. Our findings suggest that providing healthcare services online can reduce online patients’ needs to visit …


Solving The Vehicle Routing Problem With Simultaneous Pickup And Delivery And Occasional Drivers By Simulated Annealing, Vincent F. Yu, Grace Aloina, Panca Jodiawan, Aldy Gunawan, Tsung-Chi Huang Dec 2021

Solving The Vehicle Routing Problem With Simultaneous Pickup And Delivery And Occasional Drivers By Simulated Annealing, Vincent F. Yu, Grace Aloina, Panca Jodiawan, Aldy Gunawan, Tsung-Chi Huang

Research Collection School Of Computing and Information Systems

This research studies the vehicle routing problem with simultaneous pickup and delivery with an occasional driver (VRPSPDOD). VRPSPDOD is a new variant of the vehicle routing problems with simultaneous pickup and delivery (VRPSPD). Different from VRPSPD, in VRPSPDOD, occasional drivers are employed to work with regular vehicles to service customers’ pickup and delivery requests in order to minimize the total cost. We formulate a mixed integer linear programming model for VRPSPD and propose a heuristic algorithm based on simulated annealing (SA) to solve the problem. The results of comprehensive numerical experiments show that the proposed SA performs well in terms …


Statistical Moderation: A Case Study In Grading On A Curve, Manoj Thulasidas Dec 2021

Statistical Moderation: A Case Study In Grading On A Curve, Manoj Thulasidas

Research Collection School Of Computing and Information Systems

There is a negative perception about “grading on a curve,” because of the feeling that the cohort strength may skew the final grades one way or another. However, given the difficulties in ensuring absolute uniformity in assessment across the years, especially when taught and assessed by different instructors under different settings, grading on a curve may be a necessary evil. Once we accept this type of statistical moderation as the last line of defense in standardizing the final scores so that student cohorts from different terms or sections or schools may be compared, we have to implement it well. In …


Context-Aware Graph Convolutional Network For Dynamic Origin-Destination Prediction, Juan Nathaniel, Baihua Zheng Dec 2021

Context-Aware Graph Convolutional Network For Dynamic Origin-Destination Prediction, Juan Nathaniel, Baihua Zheng

Research Collection School Of Computing and Information Systems

A robust Origin-Destination (OD) prediction is key to urban mobility. A good forecasting model can reduce operational risks and improve service availability, among many other upsides. Here, we examine the use of Graph Convolutional Net-work (GCN) and its hybrid Markov-Chain (GCN-MC) variant to perform a context-aware OD prediction based on a large-scale public transportation dataset in Singapore. Compared with the baseline Markov-Chain algorithm and GCN, the proposed hybrid GCN-MC model improves the prediction accuracy by 37% and 12% respectively. Lastly, the addition of temporal and historical contextual information further improves the performance of the proposed hybrid model by 4 –12%.


Hrpdf: A Software-Based Heterogeneous Redundant Proactive Defense Framework For Programmable Logic Controller, Ke Liu, Jing-Yi Wang, Qiang Wei, Zhen-Yong Zhang, Jun Sun, Rong-Kuan Ma, Rui-Long Deng Dec 2021

Hrpdf: A Software-Based Heterogeneous Redundant Proactive Defense Framework For Programmable Logic Controller, Ke Liu, Jing-Yi Wang, Qiang Wei, Zhen-Yong Zhang, Jun Sun, Rong-Kuan Ma, Rui-Long Deng

Research Collection School Of Computing and Information Systems

Programmable logic controllers (PLCs) play a critical role in many industrial control systems, yet face increasingly serious cyber threats. In this paper, we propose a novel PLC-compatible software-based defense mechanism, called Heterogeneous Redundant Proactive Defense Framework (HRPDF). We propose a heterogeneous PLC architecture in HRPDF, including multiple heterogeneous, equivalent, and synchronous runtimes, which can thwart multiple types of attacks against PLC without the need of external devices. To ensure the availability of PLC, we also design an inter-process communication algorithm that minimizes the overhead of HRPDF. We implement a prototype system of HRPDF and test it in a real-world PLC …


Linear Algebra For Computer Science, M. Thulasidas Dec 2021

Linear Algebra For Computer Science, M. Thulasidas

Research Collection School Of Computing and Information Systems

This textbook introduces the essential concepts and practice of Linear Algebra to the undergraduate student of computer science. The focus of this book is on the elegance and beauty of the numerical techniques and algorithms originating from Linear Algebra. As a practical handbook for computer and data scientists, LA4CS restricts itself mostly to real fields and tractable discourses, rather than deep and theoretical mathematics.


Strategic Behavior And Market Inefficiency In Blockchain-Based Auctions, Ping Fan Ke, Jianqing Chen, Zhiling Guo Dec 2021

Strategic Behavior And Market Inefficiency In Blockchain-Based Auctions, Ping Fan Ke, Jianqing Chen, Zhiling Guo

Research Collection School Of Computing and Information Systems

Blockchain-based auctions play a key role in decentralized finance, such as liquidation of collaterals in crypto-lending. In this research, we show that a Blockchain-based auction is subject to the threat to availability because of the characteristics of the Blockchain platform, which could lead to auction inefficiency or even market failure. Specifically, an adversary could occupy all of the transaction capacity of an auction by sending transactions with sufficiently high transaction fees, and then win the item in an auction with a nearly zero bid price as there are no competitors available. We discuss how to prevent this kind of strategic …