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Full-Text Articles in Physical Sciences and Mathematics

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 …


Integration Of Information Technology Certifications Into Undergraduate Computing Curriculum, Eng Lieh Ouh, Kyong Jin Shim Dec 2021

Integration Of Information Technology Certifications Into Undergraduate Computing Curriculum, Eng Lieh Ouh, Kyong Jin Shim

Research Collection School Of Computing and Information Systems

This innovative practice full paper describes our experiences of integrating information technology certifications into an undergraduate computing curriculum. As the technology landscape evolves, a common challenge for educators in computing programs is designing an industry-relevant curriculum. Over the years, industry practitioners have taken technology certifications to validate themselves against a base level of technical knowledge currently in demand in industry. Information technology (IT) certifications can also offer paths for academic computing programs to stay relevant to industry needs. However, identifying relevant IT certifications and integrating it into an academic curriculum requires a careful design approach as substantial efforts are needed …


Ai And The Future Of Work: What We Know Today, Steven M. Miller, Thomas H. Davenport Dec 2021

Ai And The Future Of Work: What We Know Today, Steven M. Miller, Thomas H. Davenport

Research Collection School Of Computing and Information Systems

To contribute to a better understanding of the contemporary realities of AI workplace deployments, the authors recently completed 29 case studies of people doing their everyday work with AI-enabled smart machines. Twenty-three of these examples were from North America, mostly in the US. Six were from Southeast Asia, mostly in Singapore. In this essay, we compare our findings on job and workplace impacts to those reported in the MIT Task Force on the Work of the Future report, as we consider that to be the most comprehensive recent study on this topic.


Checking Smart Contracts With Structural Code Embedding, Zhipeng Gao, Lingxiao Jiang, Xin Xia, David Lo, John Grundy Dec 2021

Checking Smart Contracts With Structural Code Embedding, Zhipeng Gao, Lingxiao Jiang, Xin Xia, David Lo, John Grundy

Research Collection School Of Computing and Information Systems

Smart contracts have been increasingly used together with blockchains to automate financial and business transactions. However, many bugs and vulnerabilities have been identified in many contracts which raises serious concerns about smart contract security, not to mention that the blockchain systems on which the smart contracts are built can be buggy. Thus, there is a significant need to better maintain smart contract code and ensure its high reliability. In this paper, we propose an automated approach to learn characteristics of smart contracts in Solidity, useful for repetitive contract code, bug detection and contract validation. Our new approach is based on …


Butte Priority Soils Operable Unit (Bpsou) Insufficiently Reclaimed Sites - Field Sampling And Investigation Plan (Fsp) Bres No. 104 - Colorado Dump – Final, Revision 1, Mike Mcanulty Dec 2021

Butte Priority Soils Operable Unit (Bpsou) Insufficiently Reclaimed Sites - Field Sampling And Investigation Plan (Fsp) Bres No. 104 - Colorado Dump – Final, Revision 1, Mike Mcanulty

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Towards Understanding Why Lookahead Generalizes Better Than Sgd And Beyond, Pan Zhou, Hanshu Yan, Xiaotong Yuan, Jiashi Feng, Shuicheng Yan Dec 2021

Towards Understanding Why Lookahead Generalizes Better Than Sgd And Beyond, Pan Zhou, Hanshu Yan, Xiaotong Yuan, Jiashi Feng, Shuicheng Yan

Research Collection School Of Computing and Information Systems

To train networks, lookahead algorithm [1] updates its fast weights k times via an inner-loop optimizer before updating its slow weights once by using the latest fast weights. Any optimizer, e.g. SGD, can serve as the inner-loop optimizer, and the derived lookahead generally enjoys remarkable test performance improvement over the vanilla optimizer. But theoretical understandings on the test performance improvement of lookahead remain absent yet. To solve this issue, we theoretically justify the advantages of lookahead in terms of the excess risk error which measures the test performance. Specifically, we prove that lookahead using SGD as its inner-loop optimizer can …


Rmix: Learning Risk-Sensitive Policies For Cooperative Reinforcement Learning Agents, Wei Qiu, Xinrun Wang, Runsheng Yu, Xu He, Rundong Wang, Bo An, Svetlana Obraztsova, Zinovi Rabinovich Dec 2021

Rmix: Learning Risk-Sensitive Policies For Cooperative Reinforcement Learning Agents, Wei Qiu, Xinrun Wang, Runsheng Yu, Xu He, Rundong Wang, Bo An, Svetlana Obraztsova, Zinovi Rabinovich

Research Collection School Of Computing and Information Systems

Current value-based multi-agent reinforcement learning methods optimize individual Q values to guide individuals' behaviours via centralized training with decentralized execution (CTDE). However, such expected, i.e., risk-neutral, Q value is not sufficient even with CTDE due to the randomness of rewards and the uncertainty in environments, which causes the failure of these methods to train coordinating agents in complex environments. To address these issues, we propose RMIX, a novel cooperative MARL method with the Conditional Value at Risk (CVaR) measure over the learned distributions of individuals' Q values. Specifically, we first learn the return distributions of individuals to analytically calculate CVaR …


Infinite Time Horizon Safety Of Bayesian Neural Networks, Mathias Lechner, Dorde Zikelic, Krishnendu Chatterjee, Thomas A. Henzinger Dec 2021

Infinite Time Horizon Safety Of Bayesian Neural Networks, Mathias Lechner, Dorde Zikelic, Krishnendu Chatterjee, Thomas A. Henzinger

Research Collection School Of Computing and Information Systems

Bayesian neural networks (BNNs) place distributions over the weights of a neural network to model uncertainty in the data and the network’s prediction. We consider the problem of verifying safety when running a Bayesian neural network policy in a feedback loop with infinite time horizon systems. Compared to the existing sampling-based approaches, which are inapplicable to the infinite time horizon setting, we train a separate deterministic neural network that serves as an infinite time horizon safety certificate. In particular, we show that the certificate network guarantees the safety of the system over a subset of the BNN weight posterior’s support. …


Butte Priority Soils Operable Unit (Bpsou) Insufficiently Reclaimed Sites - Field Sampling Plan (Fsp) Bres No. 154 – Clark Mill Tailings Ne., Mike Mcanulty Dec 2021

Butte Priority Soils Operable Unit (Bpsou) Insufficiently Reclaimed Sites - Field Sampling Plan (Fsp) Bres No. 154 – Clark Mill Tailings Ne., Mike Mcanulty

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Butte Silver Bow Snow Management Plan, Mike Mcanulty, Eric Hassler Dec 2021

Butte Silver Bow Snow Management Plan, Mike Mcanulty, Eric Hassler

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Chicago Alliance For Equity In Computer Science, Steven Mcgee, Lucia Dettori, Ronald I. Greenberg, Andrew M. Rasmussen, Dale F. Reed, Don Yanek Dec 2021

Chicago Alliance For Equity In Computer Science, Steven Mcgee, Lucia Dettori, Ronald I. Greenberg, Andrew M. Rasmussen, Dale F. Reed, Don Yanek

Computer Science: Faculty Publications and Other Works

CAFECS is committed to ensuring that all students in Chicago participate in engaging, relevant, and rigorous computing experiences by addressing problems of practice through research and development that increases opportunities for all students to pursue computing pathways and prepares all students for the future of work.


Development Of A Magnetic Confinement Attachment For Enhanced Signal In Handheld Laser Induced Breakdown Spectroscopy Soil Analysis, Alfred C. Anderson Dec 2021

Development Of A Magnetic Confinement Attachment For Enhanced Signal In Handheld Laser Induced Breakdown Spectroscopy Soil Analysis, Alfred C. Anderson

Theses and Dissertations

Field techniques for characterizing low levels of heavy elements of less than 100 parts per million in soils tend to be unreliable because of the relatively weak signal of these elements and the large, variable background inherent to analyzing soils with minimal sample preparation. To enhance the detection and analysis capability of a handheld laser-induced breakdown spectroscopy (LIBS) instrument, this work investigates the effects of a unique magnetic confinement apparatus on signal intensities, focusing on five iron lines as well as those from actinides in 11 soil samples. The proposed magnetic confinement apparatus achieved over 0.8 T but did not …


Using Sedimentary Mercury Geochemistry To Evaluate The Niagara-Salina Transition, Silurian Michigan Basin, Usa, Sara Hayes Dec 2021

Using Sedimentary Mercury Geochemistry To Evaluate The Niagara-Salina Transition, Silurian Michigan Basin, Usa, Sara Hayes

Masters Theses

The Niagara-Salina boundary in the Michigan Basin is marked by an abrupt transition from carbonates to evaporites. Though the cause is uncertain, previous work suggests the onset of Salina evaporites was driven by basin restriction, but the presence of several global carbon isotope excursions (CIE) suggest a global driver. This study builds on this discussion using two relatively new geochemical proxies - elemental mercury concentrations [Hg] and Hg isotopes.

Mercury concentrations [Hg] were measured in 88 samples from the State Kalkaska #2-15 core from 6604.03 ft to 6797.42 ft. [Hg] ranges from 0.11 to 0.62 mg/kg and [Hg]/TOC from 0.038 …


Measuring Hydraulic Conductivity Using Flexible Walled Permeameter And Astm Method D5084, Bradon Povah Dec 2021

Measuring Hydraulic Conductivity Using Flexible Walled Permeameter And Astm Method D5084, Bradon Povah

Master of Science in Environmental Sciences and Management Projects

This project is a guide that details the protocol synthesized from the ASTM D5084-16a method, the Humboldt control panel manual, and the time spent learning the intricacies of the Permeability Cell instrument.


Risk-Based Machine Learning Approaches For Probabilistic Transient Stability, Umair Shahzad Dec 2021

Risk-Based Machine Learning Approaches For Probabilistic Transient Stability, Umair Shahzad

Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research

Power systems are getting more complex than ever and are consequently operating close to their limit of stability. Moreover, with the increasing demand of renewable wind generation, and the requirement to maintain a secure power system, the importance of transient stability cannot be overestimated. Considering its significance in power system security, it is important to propose a different approach for enhancing the transient stability, considering uncertainties. Current deterministic industry practices of transient stability assessment ignore the probabilistic nature of variables (fault type, fault location, fault clearing time, etc.). These approaches typically provide a conservative criterion and can result in expensive …


Characterization Of Infrared Metasurface Optics With An Optical Scatterometer, Matthew R. Miller Dec 2021

Characterization Of Infrared Metasurface Optics With An Optical Scatterometer, Matthew R. Miller

Theses and Dissertations

An optical scatterometer is used to characterize the infrared scatter of a dielectric metasurface cylindrical lens and two variants of that design. The design uses dielectric nanopillars to create the parabolic phase delay required for lensing; the variants change the length of the nanopillars from the design length of 4 microns to 0.9 and 5.2 microns. Scatter measurements were made at the design wavelength of 4 microns, and at 3.39 and 5 microns. These measurements showed wide-angle scatter greater than that measured for a conventional refractive optic, and that these metasurfaces perform their optical function best at the design wavelength …


Ultrafast Magnetic Entropy Dynamics With Time-Resolved Pump-Probe Magneto-Optical Technique., Sahar Goharshenasanesfahani Dec 2021

Ultrafast Magnetic Entropy Dynamics With Time-Resolved Pump-Probe Magneto-Optical Technique., Sahar Goharshenasanesfahani

Electronic Theses and Dissertations

It has been observed that ultrathin films, multilayers, or magnetic nanostructures indicate novel magnetic phenomena that differ profoundly from the respective bulk properties. Besides, because of the broad applications of these magnetic materials in the industry, they are an exciting research area. Hence, investigating the low-dimensional magnetic systems is one of the most active fields in experimental condensed matter physics. Magnetization dynamics can occur over a wide range of time scales (from seconds to femtoseconds). Some of these processes even occur on time scales as short as a few picoseconds (10-12s) or femtoseconds (10-15s). Measurement of …


Language Pre-Training And Auxiliary Tasks For Vision And Language Navigation, Saumya Bhatt Dec 2021

Language Pre-Training And Auxiliary Tasks For Vision And Language Navigation, Saumya Bhatt

Computer Science and Engineering Theses

The Vision and Language Navigation task came to life from the idea that we can build a robot or an autonomous system that can be instructed in human language and that will navigate using the instructions given. For example, we tell the agent to “Go down past some room dividers toward a glass top desk and turn into the dining area. Wait next to the large glass dining table” and not only does it reach the goal state but it follows the instructions while navigating. With the current developments, this may not seem like a distant problem anymore and in …


Adaptive Human-Robot Motion Transfer For Complete Body Imitation, Francisco Villa Dec 2021

Adaptive Human-Robot Motion Transfer For Complete Body Imitation, Francisco Villa

Computer Science and Engineering Theses

Programming robot systems to perform certain tasks is a big challenge especially if such programming is to be performed by persons who are not experts in robotics. For example, when programming a robot to serve as an exercise trainer, the person defining the motions might more naturally be a person in the exercise domain rather than a robotics expert. To address this, this thesis investigates programming by demonstration or teleoperation using full direct body motion. The goal is to reproduce gaits, gestures, and postures on a humanoid robot from observed human demonstrations. Fine motor movements such as movement of fingers …


Tectonomagmatic Evolution Of Northwestern Mexico, And Applications Of Machine Learning In Economic Geology, Jose Antonio Garcia Dec 2021

Tectonomagmatic Evolution Of Northwestern Mexico, And Applications Of Machine Learning In Economic Geology, Jose Antonio Garcia

Open Access Theses & Dissertations

The work presented here was conducted in two study areas: La Preciosa mining project (Chapters 1 and 2) and Ray Mine (Chapter 3). Chapter 1 of this dissertation contributes to the tectonomagmatic evolution of northwestern Mexico by focusing on the temporal changes in magma source(s) regions, magma generation processes, and tectonic implications. In this chapter, I provide thin section analyses, whole rock geochemistry, in-situ zircon U-Pb ages and Hf isotope compositions of subsurface lithologies from La Preciosa mining project; located in the northwestern corner of Mesa Central, Durango, Mexico. The newly acquired data identified five magmatic events. The first consists …


Synthesis, Crystal Structure And Ionic Conductivity Of Ruddlesden-Popper Oxide Materials: Effects Of Ionic Radii And Defects On Lithium-Ionic Conductivity., Selorm Joy Fanah Dec 2021

Synthesis, Crystal Structure And Ionic Conductivity Of Ruddlesden-Popper Oxide Materials: Effects Of Ionic Radii And Defects On Lithium-Ionic Conductivity., Selorm Joy Fanah

Electronic Theses and Dissertations

Layered perovskite oxides of the Ruddlesden-Popper (RP) type structure can be good lithium-ion conductors for solid electrolyte applications in all-solid-state batteries, due to the large gap separating octahedral layers which can be useful pathways for Li-ion conduction. However, little work has been done on their lithium-ion transport properties in these materials despite their interesting structural properties. This work highlights the synthesis and study of the ionic conductivities in a series of n = 2 and 3 Ruddlesden-Popper oxides, as part of an ongoing investigation in search of alternative solid electrolyte materials. Several different strategies were employed for the enhancement of …


A Remote Sensing Perspective: Mapping The Human Footprint In The Zambezi Region Of Namibia., Ariel E Weaver Dec 2021

A Remote Sensing Perspective: Mapping The Human Footprint In The Zambezi Region Of Namibia., Ariel E Weaver

Electronic Theses and Dissertations

The “human footprint” can be used as a general proxy to estimate human activities across the landscape. The human footprint in the Zambezi Region of Namibia is critically important for regional management of conservation efforts and land use planning. The land covers in the Zambezi Region are characteristically difficult to separate spectrally, due to a highly heterogeneous savanna landscape. Object Based Image Analysis (OBIA) and Random Forest (RF) methods are notable for their ability to improve classification accuracies of remotely sensed imagery. In this study, I investigate the extent of the human footprint in the Zambezi Region of Namibia, using …


Theoretical Investigation Of The Co-C Bond Activation In Methylcobalamin And Adenosylcobalamin-Dependent Systems: Mechanistic Insights., Arghya Pratim Ghosh Dec 2021

Theoretical Investigation Of The Co-C Bond Activation In Methylcobalamin And Adenosylcobalamin-Dependent Systems: Mechanistic Insights., Arghya Pratim Ghosh

Electronic Theses and Dissertations

The vitamin B12 derivates, otherwise known as cobalamin (Cbl), are ubiquitous organometallic cofactors. The biologically active forms of Cbl, such as methylcobalamin (MeCbl) and adenosylcobalamin (AdoCbl), act as cofactors in different physiological reactions for both prokaryotes and eukaryotes. A crucial aspect of the Cbl-mediated systems is the activation of the organometallic Co-C bond that plays a critical role in its catalytic activity. One of the most remarkable features of this Co-C bond is its unusual activation in AdoCbl-dependent enzymatic reactions, where a trillion-fold rate acceleration of the Co-C bond cleavage is observed inside the enzyme compared to the isolated …


Finite Groups In Which The Number Of Cyclic Subgroups Is 3/4 The Order Of The Group, James Alexander Cayley Dec 2021

Finite Groups In Which The Number Of Cyclic Subgroups Is 3/4 The Order Of The Group, James Alexander Cayley

MSU Graduate Theses

Let $G$ be a finite group, c(G) denotes the number of cyclic subgroups of G and α(G) = c(G)/|G|. In this thesis we go over some basic properties of alpha, calculate alpha for some families of groups, with an emphasis on groups with α(G) = 3/4, as all groups with α(G) > 3/4 have been classified by Garonzi and Lima (2018). We find all Dihedral group with this property, show all groups with α(G) = 3/4 have at least |G|/2-1 involutions, and discuss existing work by Wall (1970) and Miller (1919) classifying all such groups.


Cover Crop Effects On Near-Surface Soil Aggregate Stability In The Southern Mississippi Valley Loess (Mlra 134), Chandler M. Arel Dec 2021

Cover Crop Effects On Near-Surface Soil Aggregate Stability In The Southern Mississippi Valley Loess (Mlra 134), Chandler M. Arel

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

Intensive agricultural cultivation within major land resource area (MLRA) 134, the Southern Mississippi Valley Loess, has led to soil erosion, soil compaction, and the overall destabilization of near-surface soil aggregates. The use of cover crops during the agricultural offseason has been shown to help alleviate soil compaction and provide stabilizing effects against soil erosion, which are particularly important as the silty soils of MLRA 134 have a large erosion potential. This study evaluated the effects of cover crop and no-cover crop treatment on silt-loam soils within MLRA 134. Treatments were implemented during Fall 2018 and Fall 2019 and consisted of …


Computational Investigations Of The Photochemical Properties Of B12-Dependent Systems: From Solution To Enzymes., Megan Toda Mackintosh Dec 2021

Computational Investigations Of The Photochemical Properties Of B12-Dependent Systems: From Solution To Enzymes., Megan Toda Mackintosh

Electronic Theses and Dissertations

The photochemical properties of the B12 family of molecules (cobalamins = Cbls) have been known for many years yet only until the 21st century have applications for the light-sensitivity of Cbls come to the surface. Photolabile Cbls can be used for the delivery of therapeutics with spatial and temporal control, in the generation of hydroxyl radicals, and in nature, as demonstrated in the catalytic cycle of coenzyme B12-dependent photoreceptors. This dissertation describes the use of computational methods to explore the photochemical properties of Cbl systems including antivitamins B12, a thiolato-cobalamin, and the coenzyme B …


Specific Splice Junction Detection In Single Cells With Sicilian, Roozbeh Dehghannasiri, Julia E. Olivieri, Ana Damljanovic, Julia Salzman Dec 2021

Specific Splice Junction Detection In Single Cells With Sicilian, Roozbeh Dehghannasiri, Julia E. Olivieri, Ana Damljanovic, Julia Salzman

All Faculty Articles - School of Engineering and Computer Science

Precise splice junction calls are currently unavailable in scRNA-seq pipelines such as the 10x Chromium platform but are critical for understanding single-cell biology. Here, we introduce SICILIAN, a new method that assigns statistical confidence to splice junctions from a spliced aligner to improve precision. SICILIAN is a general method that can be applied to bulk or single-cell data, but has particular utility for single-cell analysis due to that data’s unique challenges and opportunities for discovery. SICILIAN’s precise splice detection achieves high accuracy on simulated data, improves concordance between matched single-cell and bulk datasets, and increases agreement between biological replicates. SICILIAN …


Synthesis Of Phytosulfokine Analogs As Probes For Studying Plant Signaling And Molecular Trafficking, Thomas Ntim Dec 2021

Synthesis Of Phytosulfokine Analogs As Probes For Studying Plant Signaling And Molecular Trafficking, Thomas Ntim

Electronic Theses and Dissertations

Plants are exposed to a wide range of biotic and abiotic stresses that hinder their growth and reduce crop productivity. In their adaptive response, plants use signaling molecules that are trafficked throughout the plant. This research focuses on the chemical synthesis and assessment of analogs of the plant signal phytosulfokine (PSK, a sulfated pentapeptide), its delivery to plants and its observation using a fiber-optic fluorescence microscope. PSK regulates growth, cell expansion, heat tolerance, and tissue longevity. Analogs of PSK were synthesized using solid-phase peptide synthesis. Pure PSK and TAMRA-labeled PSK were delivered into the wild-type Arabidopsis thaliana Col-0 and a …


Efficient Data Structures For Text Processing Applications, Paniz Abedin Dec 2021

Efficient Data Structures For Text Processing Applications, Paniz Abedin

Electronic Theses and Dissertations, 2020-2023

This thesis is devoted to designing and analyzing efficient text indexing data structures and associated algorithms for processing text data. The general problem is to preprocess a given text or a collection of texts into a space-efficient index to quickly answer various queries on this data. Basic queries such as counting/reporting a given pattern's occurrences as substrings of the original text are useful in modeling critical bioinformatics applications. This line of research has witnessed many breakthroughs, such as the suffix trees, suffix arrays, FM-index, etc. In this work, we revisit the following problems: 1. The Heaviest Induced Ancestors problem 2. …


Wavelet Particle Hydrodynamics For Less Smooth Flow, Oddny Brun Dec 2021

Wavelet Particle Hydrodynamics For Less Smooth Flow, Oddny Brun

Electronic Theses and Dissertations, 2020-2023

The purpose of this research was to improve the smoothing operation in smoothed particle hydrodynamics, SPH, when the flow of matter is not smooth. Our main focuses are on the kernel selection, identifying the discontinuities in the sequences to be smoothed, and use of the Laplacian as opposed to artificial viscosity for improved physical accuracy. The results show that alternative kernels result in differences in how matter flows. These effects are explained by the kernels' gradient and Laplacian properties. Five alternative kernels were included in our analysis and our SPH-based simulation cases. Further, the sequences to be smoothed by the …