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Enhanced Two-Step Deep-Learning Approach For Electromagnetic-Inverse-Scattering Problems: Frequency Extrapolation And Scatterer Reconstruction, Huan Huan Zhang, He Ming Yao, Lijun Jiang, Michael Ng Feb 2023

Enhanced Two-Step Deep-Learning Approach For Electromagnetic-Inverse-Scattering Problems: Frequency Extrapolation And Scatterer Reconstruction, Huan Huan Zhang, He Ming Yao, Lijun Jiang, Michael Ng

Electrical and Computer Engineering Faculty Research & Creative Works

The electromagnetic-inverse-scattering (EMIS) problem is solved by a novel two-step deep-learning (DL) approach in this article. The newly proposed two-step DL approach not only predicts the multifrequency EM scattered field, but also overcomes the limitation of the conventional methods for solving EMIS problems, such as expensive computational cost, strong ill-conditions, and invalidity on high contrast. In the first step, the complex-valued deep residual convolutional neural network (DRCNN) is utilized to predict multifrequency EM scattered fields only using single-frequency EM scattered field information. Based on a new complex-valued deep convolutional encoder-decoder (DCED) structure, the second step utilizes the obtained multifrequency EM …

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Sra Inhibition Improves Antitumor Potency Of Antigen-Targeted Chaperone Vaccine, Jie Qian, Xiaofei Yu, Zheng Liu, Jinyang Cai, Masoud H. Manjili, Hu Yang, Chunqing Guo, Xiang Yang Wang Jan 2023

Sra Inhibition Improves Antitumor Potency Of Antigen-Targeted Chaperone Vaccine, Jie Qian, Xiaofei Yu, Zheng Liu, Jinyang Cai, Masoud H. Manjili, Hu Yang, Chunqing Guo, Xiang Yang Wang

Chemical and Biochemical Engineering Faculty Research & Creative Works

We Have Previously Demonstrated that Scavenger Receptor a (SRA) Acts as an Immunosuppressive Regulator of Dendritic Cell (DC) Function in Activating Antitumor T Cells. Here We Investigate the Potential of Inhibiting SRA Activity to Enhance DC-Targeted Chaperone Vaccines Including One that Was Recently Evaluated in Melanoma Patients. We Show that Short Hairpin RNA-Mediated SRA Silencing Significantly Enhances the Immunogenicity of DCs that Have Captured Chaperone Vaccines Designed to Target Melanoma (I.e., Hsp110-Gp100) and Breast Cancer (I.e., Hsp110-HER/Neu-ICD). SRA Downregulation Results in Heightened Activation of Antigen-Specific T Cells and Increased CD8+ T Cell-Dependent Tumor Inhibition. Additionally, Small Interfering RNA (SiRNA) Complexed …

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The Visualization Of Orphadata Neurology Phenotypes, Daniel B. Hier, Raghu Yelugam, Michael D. Carrithers, Donald C. Wunsch Jan 2023

The Visualization Of Orphadata Neurology Phenotypes, Daniel B. Hier, Raghu Yelugam, Michael D. Carrithers, Donald C. Wunsch

Electrical and Computer Engineering Faculty Research & Creative Works

Disease Phenotypes Are Characterized by Signs (What a Physician Observes during the Examination of a Patient) and Symptoms (The Complaints of a Patient to a Physician). Large Repositories of Disease Phenotypes Are Accessible through the Online Mendelian Inheritance of Man, Human Phenotype Ontology, and Orpha data Initiatives. Many of the Diseases in These Datasets Are Neurologic. for Each Repository, the Phenotype of Neurologic Disease is Represented as a List of Concepts of Variable Length Where the Concepts Are Selected from a Restricted Ontology. Visualizations of These Concept Lists Are Not Provided. We Address This Limitation by using Subsumption to Reduce …

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Methods For Determining The Infrared Complex Refractive Indices N(Λ) And K(Λ) From Organic Solid Powders: Comparison Of A Sucrose Single Crystal And A Pressed Pellet, Michael O. Yokosuk, Danielle L. Saunders, Charles Tom Resch, Jeremy D. Erickson, Charmayne E. Lonergan, Sarah D. Burton, Mark E. Bowden, Kelly A. Peterson, Timothy J. Johnson, Tanya L. Myers Jan 2023

Methods For Determining The Infrared Complex Refractive Indices N(Λ) And K(Λ) From Organic Solid Powders: Comparison Of A Sucrose Single Crystal And A Pressed Pellet, Michael O. Yokosuk, Danielle L. Saunders, Charles Tom Resch, Jeremy D. Erickson, Charmayne E. Lonergan, Sarah D. Burton, Mark E. Bowden, Kelly A. Peterson, Timothy J. Johnson, Tanya L. Myers

Materials Science and Engineering Faculty Research & Creative Works

There exists a need to measure optical constants n and k for many materials, especially organic solids in the infrared spectral region, but at present, there are only two established methods for making such measurements: single-angle (SA) reflectance and infrared spectroscopic ellipsometry (IRSE). the former derives the n/k vectors via measurement of the change in the amplitude of light reflected from the sample and then uses the Kramers-Kronig transform, while the latter measures the change in polarization of the reflected light from the sample to derive n/k. Here we make a direct comparison between the n/k vectors derived from SA …

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Lysine Crosslinked Polyacrylamide─A Novel Green Polymer Gel For Preferential Flow Control, Tao Song, Baojun Bai, Yugandhara Eriyagama, Thomas P. Schuman Jan 2023

Lysine Crosslinked Polyacrylamide─A Novel Green Polymer Gel For Preferential Flow Control, Tao Song, Baojun Bai, Yugandhara Eriyagama, Thomas P. Schuman

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Acrylamide-based polymer gels have been applied to control the preferential flow in the subsurface for decades. However, some commonly used crosslinkers, such as Cr (III) and phenol-formaldehyde, are highly toxic and are being phased out because of stringent environmental regulations. This work uses l-lysine as the green crosslinker to produce acrylamide-based polymer gels. This article systematically studied the effect of lysine and polymer concentration, salinity, pH, and temperature on gelation behavior and thermal stability. Besides, the gelation mechanism and crosslinking density were elucidated in this work. A high-permeability sandstone core was used to test the plugging efficiency of this novel …

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The Kanarra Fold-Thrust Structure - The Leading Edge Of The Sevier Fold-Thrust Belt, Southwestern Utah: Geology Of The Intermountain West, William J. Chandonia, John P. Hogan Jan 2023

The Kanarra Fold-Thrust Structure - The Leading Edge Of The Sevier Fold-Thrust Belt, Southwestern Utah: Geology Of The Intermountain West, William J. Chandonia, John P. Hogan

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The multiple origins proposed for the Kanarra anticline in southwestern Utah as a drag-fold along the Hurricane fault, a Laramide monocline, a Sevier fault-propagation fold, or a combination of these process­es, serve to muddy its tectonic significance. This in part reflects the structural complexity of the exposed eastern half of the fold. The fold evolved from open and up-right to overturned and tight, is cross-cut by multiple faults, and was subsequently dismembered by the Hurricane fault. The western half of the fold is obscured because of burial, along with the hanging wall of the Hurricane fault, beneath Neogene and younger …

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Direct Synthesis Of Ethylene And Hydrogen From Co2 And Ethane Over A Bifunctional Structured Cao/Cr2o3-V2o5/Zsm-5 Adsorbent/Catalyst Monolith, Khaled Baamran, Ali A. Rownaghi, Fateme Rezaei Jan 2023

Direct Synthesis Of Ethylene And Hydrogen From Co2 And Ethane Over A Bifunctional Structured Cao/Cr2o3-V2o5/Zsm-5 Adsorbent/Catalyst Monolith, Khaled Baamran, Ali A. Rownaghi, Fateme Rezaei

Chemical and Biochemical Engineering Faculty Research & Creative Works

In this study, we synthesized bifunctional adsorbent/catalyst materials (BFMs) consisting of a CaO adsorbent admixed with Cr2O3-V2O5/ZSM-5 catalysts. The obtained BFMs were further formulated, processed, and shaped through additive manufacturing (3D printing) method. The physical and chemical properties of structured CaO/Cr2O3-V2O5/ZSM-5 adsorbent/catalyst monoliths were thoroughly characterized and evaluated. The effects of operating conditions including reaction temperature, ethane composition, and space velocity on single-bed CO2 capture and selective formation of ethylene and hydrogen were systematically investigated. The adsorption-reaction experiments revealed …

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Biological Anolyte Regeneration System For Redox Flow Batteries, Olja Simoska, Zayn Rhodes, Emily Carroll, Katia N. Petrosky, Shelley D. Minteer Jan 2023

Biological Anolyte Regeneration System For Redox Flow Batteries, Olja Simoska, Zayn Rhodes, Emily Carroll, Katia N. Petrosky, Shelley D. Minteer

Chemistry Faculty Research & Creative Works

Redox flow battery (RFB) electrolyte degradation is a common failure mechanism in RFBs. We report an RFB using genetically engineered, phenazine-producing Escherichia coli to serve as an anolyte regeneration system capable of repairing the degraded/decomposed redox-active phenazines. This work represents a new strategy for improving the stability of RFB systems because, under the influence of genetically engineered microbes, the anolyte species does not display degradation after battery cycling.

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Adoption Of Astm A956-06 Leeb Hardness Testing Standard To Rock Engineering Applications, Sasan Ghorbani, Seyed Hadi Hoseinie, Ebrahim Ghasemi, Taghi Sherizadeh Jan 2023

Adoption Of Astm A956-06 Leeb Hardness Testing Standard To Rock Engineering Applications, Sasan Ghorbani, Seyed Hadi Hoseinie, Ebrahim Ghasemi, Taghi Sherizadeh

Mining Engineering Faculty Research & Creative Works

The Leeb dynamic hardness test was originally developed for metallic materials and is now widely used in rock engineering and engineering geology. This study aims to fundamentally investigate the application conditions of the Leeb hardness test in rock engineering because it is a high-precision, fast, nondestructive, and portable method. Therefore, four main limitations of the Leeb method mentioned in ASTM A956-06 have been further analyzed. The important challenges, including scale effect, temperature effect, surface roughness effect, and the effect of physical properties on the Leeb method, have been studied. For this purpose, 33 rock samples with a wide range of …

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A Bilevel Game-Theoretic Decision-Making Framework For Strategic Retailers In Both Local And Wholesale Electricity Markets, Qiuyi Hong, Fanlin Meng, Jian Liu, Rui Bo Jan 2023

A Bilevel Game-Theoretic Decision-Making Framework For Strategic Retailers In Both Local And Wholesale Electricity Markets, Qiuyi Hong, Fanlin Meng, Jian Liu, Rui Bo

Electrical and Computer Engineering Faculty Research & Creative Works

This paper proposes a bilevel game-theoretic model for multiple strategic retailers participating in both wholesale and local electricity markets while considering customers' switching behaviors. At the upper level, each retailer maximizes its own profit by making optimal pricing decisions in the retail market and bidding decisions in the day-ahead wholesale (DAW) and local power exchange (LPE) markets. The interaction among multiple strategic retailers is formulated using the Bertrand competition model. For the lower level, there are three optimization problems. First, the welfare maximization problem is formulated for customers to model their switching behaviors among different retailers. Second, a market-clearing problem …

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The Effects Of Phosphorus Pentoxide Additions On The Thermal, Rheological, And Structural Properties Of Sodium Borosilicate Glass, K. L. Skerratt-Love, J. L. George, A. M.T. Bell, F. Sweeney, D. Cutforth, C. (Charmayne) E. Lonergan, D. R. Dixon, A. A. Kruger, P. A. Bingham Jan 2023

The Effects Of Phosphorus Pentoxide Additions On The Thermal, Rheological, And Structural Properties Of Sodium Borosilicate Glass, K. L. Skerratt-Love, J. L. George, A. M.T. Bell, F. Sweeney, D. Cutforth, C. (Charmayne) E. Lonergan, D. R. Dixon, A. A. Kruger, P. A. Bingham

Materials Science and Engineering Faculty Research & Creative Works

This research has characterized the effects of P2O5 additions on the physical, chemical, thermal, rheological properties and the structure of SiO2-B2O3-Na2O glasses relevant to radioactive waste immobilization. Properties analyzed include high-temperature viscosity, glass transition temperature (Tg) and structure. X-ray diffraction (XRD) confirmed a solubility limit of between 3.0 and 4.0 mol% P2O5 for the onset of crystallinity with formation of Na3PO4 and Na4P2O7 in annealed bulk glasses; and between 4.0 and 5.0 mol% P2O …

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Network Structures And The Properties Of Na-Ca-Sr-Borophosphate Glasses, Parker T. Freudenberger, Rebekah L. Blatt, Randall E. Youngman, Richard K. Brow Jan 2023

Network Structures And The Properties Of Na-Ca-Sr-Borophosphate Glasses, Parker T. Freudenberger, Rebekah L. Blatt, Randall E. Youngman, Richard K. Brow

Materials Science and Engineering Faculty Research & Creative Works

Borophosphate glasses were prepared with the nominal molar compositions 16Na2O-(24-y)CaO-ySrO-xB2O3-(60-x)P2O5 (mol%), where 0≤x≤60 and y=0, 12, and 24. Information about the compositional dependence of borate and phosphate site speciation and next nearest neighbor linkages was obtained by 11B and 31P MAS NMR and Raman spectroscopies, and by high pressure liquid chromatography (HPLC). With the initial replacement of P2O5 by B2O3, tetrahedral borate sites linked to four phosphate anions, B(ØP)4, are created in the glass structure, and the average phosphate anion becomes smaller as bridging PØP bonds are replaced by bridging PØB bonds. With further increases in the B2O3 content, borate …

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Network Structures And The Properties Of Na-Ca-Sr-Borophosphate Glasses, Parker T. Freudenberger, Rebekah L. Blatt, Randall E. Youngman, Richard K. Brow Jan 2023

Network Structures And The Properties Of Na-Ca-Sr-Borophosphate Glasses, Parker T. Freudenberger, Rebekah L. Blatt, Randall E. Youngman, Richard K. Brow

Materials Science and Engineering Faculty Research & Creative Works

Borophosphate glasses were prepared with the nominal molar compositions 16Na2O-(24-y)CaO-ySrO-xB2O3-(60-x)P2O5 (mol%), where 0≤x≤60 and y=0, 12, and 24. Information about the compositional dependence of borate and phosphate site speciation and next nearest neighbor linkages was obtained by 11B and 31P MAS NMR and Raman spectroscopies, and by high pressure liquid chromatography (HPLC). With the initial replacement of P2O5 by B2O3, tetrahedral borate sites linked to four phosphate anions, B(ØP)4, are created in the glass structure, and the average phosphate anion …

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Network Structures And The Properties Of Na-Ca-Sr-Borophosphate Glasses, Parker T. Freudenberger, Rebekah L. Blatt, Randall E. Youngman, Richard K. Brow Jan 2023

Network Structures And The Properties Of Na-Ca-Sr-Borophosphate Glasses, Parker T. Freudenberger, Rebekah L. Blatt, Randall E. Youngman, Richard K. Brow

Mathematics and Statistics Faculty Research & Creative Works

Borophosphate glasses were prepared with the nominal molar compositions 16Na2O-(24-y)CaO-ySrO-xB2O3-(60-x)P2O5 (mol%), where 0≤x≤60 and y=0, 12, and 24. Information about the compositional dependence of borate and phosphate site speciation and next nearest neighbor linkages was obtained by 11B and 31P MAS NMR and Raman spectroscopies, and by high pressure liquid chromatography (HPLC). With the initial replacement of P2O5 by B2O3, tetrahedral borate sites linked to four phosphate anions, B(ØP)4, are created in the glass structure, and the average phosphate anion becomes smaller as bridging PØP bonds are replaced by bridging PØB bonds. With further increases in the B2O3 content, borate …

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Subtypes Of Relapsing-Remitting Multiple Sclerosis Identified By Network Analysis, Quentin Howlett-Prieto, Chelsea Oommen, Michael D. Carrithers, Donald C. Wunsch, Daniel B. Hier Jan 2023

Subtypes Of Relapsing-Remitting Multiple Sclerosis Identified By Network Analysis, Quentin Howlett-Prieto, Chelsea Oommen, Michael D. Carrithers, Donald C. Wunsch, Daniel B. Hier

Electrical and Computer Engineering Faculty Research & Creative Works

We used network analysis to identify subtypes of relapsing-remitting multiple sclerosis subjects based on their cumulative signs and symptoms. The electronic medical records of 113 subjects with relapsing-remitting multiple sclerosis were reviewed, signs and symptoms were mapped to classes in a neuro-ontology, and classes were collapsed into sixteen superclasses by subsumption. After normalization and vectorization of the data, bipartite (subject-feature) and unipartite (subject-subject) network graphs were created using NetworkX and visualized in Gephi. Degree and weighted degree were calculated for each node. Graphs were partitioned into communities using the modularity score. Feature maps visualized differences in features by community. Network …

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Poly(Pro-Curcumin) Materials Exhibit Dual Release Rates And Prolonged Antioxidant Activity As Thin Films And Self-Assembled Particles, Ruiwen Chen, Jessica L. Funnell, Geraldine B. Quinones, Marvin Bentley, Jeffrey R. Capadona, Ryan J. Gilbert, Edmund F. Palermo Jan 2023

Poly(Pro-Curcumin) Materials Exhibit Dual Release Rates And Prolonged Antioxidant Activity As Thin Films And Self-Assembled Particles, Ruiwen Chen, Jessica L. Funnell, Geraldine B. Quinones, Marvin Bentley, Jeffrey R. Capadona, Ryan J. Gilbert, Edmund F. Palermo

Chemical and Biochemical Engineering Faculty Research & Creative Works

Curcumin is a natural polyphenol that exhibits remarkable antioxidant and anti-inflammatory activities; however, its clinical application is limited in part by its physiological instability. Here, we report the synthesis of curcumin-derived polyesters that release curcumin upon hydrolytic degradation to improve curcumin stability and solubility in physiological conditions. Curcumin was incorporated in the polymer backbone by a one-pot condensation polymerization in the presence of sebacoyl chloride and polyethylene glycol (PEG, Mn = 1 kDa). The thermal and mechanical properties, surface wettability, self-assembly behavior, and drug-release kinetics all depend sensitively on the mole percentage of curcumin incorporated in these statistical copolymers. Curcumin …

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Three-Stage Conversion Of Chemically Inert N-Heptane To Α-Hydrazino Aldehyde Based On Bioelectrocatalytic C-H Bond Oxyfunctionalization, N. Samali Weliwatte, Hui Chen, Tianhua Tang, Shelley D. Minteer Jan 2023

Three-Stage Conversion Of Chemically Inert N-Heptane To Α-Hydrazino Aldehyde Based On Bioelectrocatalytic C-H Bond Oxyfunctionalization, N. Samali Weliwatte, Hui Chen, Tianhua Tang, Shelley D. Minteer

Chemistry Faculty Research & Creative Works

Simple petrochemical feedstocks are often the starting material for the synthesis of complex commodity and fine and specialty chemicals. Designing synthetic pathways for these complex and specific molecular structures with sufficient chemo-, regio-, enantio-, and diastereo-selectivity can expand the existing petrochemicals landscape. the two overarching challenges in designing such pathways are selective activation of chemically inert C-H bonds in hydrocarbons and systematic functionalization to synthesize complex structures. Multienzyme cascades are becoming a growing means of overcoming the first challenge. However, extending multienzyme cascade designs is restricted by the arsenal of enzymes currently at our disposal and the compatibility between specific …

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A Parallel Framework For Efficiently Updating Graph Properties In Large Dynamic Networks, Arindam Khanda, Sajal K. Das Jan 2023

A Parallel Framework For Efficiently Updating Graph Properties In Large Dynamic Networks, Arindam Khanda, Sajal K. Das

Computer Science Faculty Research & Creative Works

Graph queries on large networks leverage the stored graph properties to provide faster results. Since real-world graphs are mostly dynamic, i.e., the graph topology changes over time, the corresponding graph attributes also change over time. In certain situations, recompiling or updating earlier properties is necessary to maintain the accuracy of a response to a graph query. Here, we first propose a generic framework for developing parallel algorithms to update graph properties on large dynamic networks. We use our framework to develop algorithms for updating Single Source Shortest Path (SSSP) and Vertex Color. Then we propose applications of the developed algorithms …

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Scalable Skill-Oriented Task Allocation In Crowdsourcing Within A Serverless Ecosystem, Biswajeet Sethi, Riya Samanta, Soumya K. Ghosh, Sajal K. Das Jan 2023

Scalable Skill-Oriented Task Allocation In Crowdsourcing Within A Serverless Ecosystem, Biswajeet Sethi, Riya Samanta, Soumya K. Ghosh, Sajal K. Das

Computer Science Faculty Research & Creative Works

Allocating the most competent crowdworkers to each upcoming task is a fundamental challenge in crowdsourcing. The mechanism becomes complicated when the arriving tasks require a high level of expertise within a constrained budget. The validation of skill matching between tasks and crowdworkers adds a new dimension to the traditional problem of task allocation. In addition, in real-world scenarios, the influx of both tasks and workers is dynamic, making it nearly impossible to predict the precise amount of computational resources required for the crowdsourcing platform to operate efficiently. Serverless computing is a new pay-per-use, auto-scalable, Function-as-a-Service based model, that ensures parallel …

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A Dtn-Based Spatio-Temporal Routing Using Location Prediction Model In Underground Mines, Abhay Goyal, Sanjay Kumar Madria, Samuel Frimpong Jan 2023

A Dtn-Based Spatio-Temporal Routing Using Location Prediction Model In Underground Mines, Abhay Goyal, Sanjay Kumar Madria, Samuel Frimpong

Computer Science Faculty Research & Creative Works

Situational awareness during any disaster depends on effective communication and location tracking. In the case of underground mines, where the communication methods are mostly central, the whole communication channel would be rendered unusable during a disaster. To this end, we propose the use of Delay Tolerant Networks (DTN) to allow the miners to function in a distributed manner and help in locating the injured miners and routing distress messages. Due to the unavailability of GPS signals, the pillar numbers are used to identify the locations of the miners. For spatio-temporal routing of messages, we formulate a new scheme using Contact …

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A Parallel Framework For Efficiently Updating Graph Properties In Large Dynamic Networks, Arindam Khanda, Sajal K. Das Jan 2023

A Parallel Framework For Efficiently Updating Graph Properties In Large Dynamic Networks, Arindam Khanda, Sajal K. Das

Computer Science Faculty Research & Creative Works

Graph queries on large networks leverage the stored graph properties to provide faster results. Since real-world graphs are mostly dynamic, i.e., the graph topology changes over time, the corresponding graph attributes also change over time. In certain situations, recompiling or updating earlier properties is necessary to maintain the accuracy of a response to a graph query. Here, we first propose a generic framework for developing parallel algorithms to update graph properties on large dynamic networks. We use our framework to develop algorithms for updating Single Source Shortest Path (SSSP) and Vertex Color. Then we propose applications of the developed algorithms …

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Sptframe: A Framework For Spatio-Temporal Information Aware Message Dissemination In Software Defined Vehicular Networks, Ankur Nahar, Debasis Das, Sajal K. Das Jan 2023

Sptframe: A Framework For Spatio-Temporal Information Aware Message Dissemination In Software Defined Vehicular Networks, Ankur Nahar, Debasis Das, Sajal K. Das

Computer Science Faculty Research & Creative Works

The volume of vehicular network traffic is very context (time and geographic location) and technology-dependent. Considering both multi-hop geocast and single-hop broadcast techniques, the route availability can be affected by transient and permanent traffic variations. Therefore, our research tackles one of the most pressing challenges in vehicular ad-hoc networks (VANETs), i.e., accommodating fine-grained spatio-temporal variance in vehicular density over time and space. This article proposes a new framework called SpTFrame to achieve fast message dissemination. The proposed approach uses a software-defined vehicular networks (SDVNs) architecture along with a deep reinforcement learning (DRL) model. SpTFrame employs a convolutional neural network (CNN) …

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Rotation-Inversion Isomerization Of Tertiary Carbamates: Potential Energy Surface Analysis Of Multi-Paths Isomerization Using Boltzmann Statistics, Brian Jameson, Rainer Glaser Jan 2023

Rotation-Inversion Isomerization Of Tertiary Carbamates: Potential Energy Surface Analysis Of Multi-Paths Isomerization Using Boltzmann Statistics, Brian Jameson, Rainer Glaser

Chemistry Faculty Research & Creative Works

Potential energy surface (PES) analyses at the SMD[MP2/6–311++G(d,p)] level and higher-level energies up to MP4(fc,SDTQ) are reported for the fluorinated tertiary carbamate N-ethyl-N-(2,2,2-trifluoroethyl) methyl carbamate (VII) and its parent system N,N-dimethyl methyl carbamate (VI). Emphasis is placed on the analysis of the rotational barrier about the CN carbamate bond and its interplay with the hybridization of the N-lone pair (NLP). All rotational transition state (TS) structures were found by computation of 1D relaxed rotational profiles but only 2D PES scans revealed the rotation-inversion paths in a compelling fashion. We found four unique chiral minima of VII, one pair each of …

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Rotation-Inversion Isomerization Of Tertiary Carbamates: Potential Energy Surface Analysis Of Multi-Paths Isomerization Using Boltzmann Statistics, Brian Jameson, Rainer Glaser Jan 2023

Rotation-Inversion Isomerization Of Tertiary Carbamates: Potential Energy Surface Analysis Of Multi-Paths Isomerization Using Boltzmann Statistics, Brian Jameson, Rainer Glaser

Chemistry Faculty Research & Creative Works

The front cover artwork is provided by Prof. Rainer Glaser's group at the Missouri University of Science and Technology. The image shows one of four potential energy surfaces generated from our rotation-inversion study of tertiary carbamates and highlights two of the eight possible transition state pathways between two ensembles of E- and Z-minima. In the context of synthetic studies of fluorinated carbamates R1 O-CO-N(R2 )CH2 CF3, we unexpectedly observed two sets of 13C NMR quartets for the CF3 group and we needed to understand their origin. Read the full text of the Research Article at …

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Variability Of Hybridization In Topminnows, David D. Duvernell Jan 2023

Variability Of Hybridization In Topminnows, David D. Duvernell

Biological Sciences Faculty Research & Creative Works

Pairs of species that exhibit broadly overlapping distributions, and multiple geographically isolated contact zones, provide opportunities to investigate the mechanisms of reproductive isolation. Such naturally replicated systems have demonstrated that hybridization rates can vary substantially among populations, raising important questions about the genetic basis of reproductive isolation. The topminnows, Fundulus notatus and F. olivaceus, are reciprocally monophyletic, and co-occur in drainages throughout much of the central and southern United States. Hybridization rates vary substantially among populations in isolated drainage systems. We employed genome-wide sampling to investigate geographic variation in hybridization, and to assess the possible importance of chromosome fusions …

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Inequalities For Interval-Valued Riemann Diamond-Alpha Integrals, Martin Bohner, Linh Nguyen, Baruch Schneider, Tri Truong Jan 2023

Inequalities For Interval-Valued Riemann Diamond-Alpha Integrals, Martin Bohner, Linh Nguyen, Baruch Schneider, Tri Truong

Mathematics and Statistics Faculty Research & Creative Works

We propose the concept of Riemann diamond-alpha integrals for time scales interval-valued functions. We first give the definition and some properties of the interval Riemann diamond-alpha integral that are naturally investigated as an extension of interval Riemann nabla and delta integrals. With the help of the interval Riemann diamond-alpha integral, we present interval variants of Jensen inequalities for convex and concave interval-valued functions on an arbitrary time scale. Moreover, diamond alpha Hölder's and Minkowski's interval inequalities are proved. Also, several numerical examples are provided in order to illustrate our main results.

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Oscillation Of Second-Order Half-Linear Neutral Noncanonical Dynamic Equations, Martin Bohner, Hassan El-Morshedy, Said Grace, Irena Jadlovská Jan 2023

Oscillation Of Second-Order Half-Linear Neutral Noncanonical Dynamic Equations, Martin Bohner, Hassan El-Morshedy, Said Grace, Irena Jadlovská

Mathematics and Statistics Faculty Research & Creative Works

In This Paper, We Shall Establish Some New Criteria for the Oscillation of Certain Second-Order Noncanonical Dynamic Equations with a Sublinear Neutral Term. This Task is Accomplished by Reducing the Involved Nonlinear Dynamic Equation to a Second-Order Linear Dynamic Inequality. We Also Establish Some New Oscillation Theorems Involving Certain Integral Conditions. Three Examples, Illustrating Our Results, Are Presented. Our Results Generalize Results for Corresponding Differential and Difference Equations.

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Trilinear Immersed-Finite-Element Method For Three-Dimensional Anisotropic Interface Problems In Plasma Thrusters, Yajie Han, Guangqing Xia, Chang Lu, Xiaoming He Jan 2023

Trilinear Immersed-Finite-Element Method For Three-Dimensional Anisotropic Interface Problems In Plasma Thrusters, Yajie Han, Guangqing Xia, Chang Lu, Xiaoming He

Mathematics and Statistics Faculty Research & Creative Works

Accurately solving the anisotropic interface problem is one of the difficulties in aerospace plasma applications. Based on cubic Cartesian meshes, this paper develops a trilinear nonhomogeneous immersed finite element (IFE) method for solving the complex anisotropic 3D elliptic interface model with nonhomogeneous flux jump. Compared with the existing 3D linear IFE spaces based on tetrahedron meshes, the newly designed trilinear IFE space for the target model simplifies the mesh generation, significantly reduces the number of mesh elements and interface elements, provides much more convenient and efficient ways for finding the intersections between interfaces and mesh edges, and decreases the errors. …

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Variable-Dependent Partial Dimension Reduction, Lu Li, Kai Tan, Xuerong Meggie Wen, Zhou Yu Jan 2023

Variable-Dependent Partial Dimension Reduction, Lu Li, Kai Tan, Xuerong Meggie Wen, Zhou Yu

Mathematics and Statistics Faculty Research & Creative Works

Sufficient dimension reduction reduces the dimension of a regression model without loss of information by replacing the original predictor with its lower-dimensional linear combinations. Partial (sufficient) dimension reduction arises when the predictors naturally fall into two sets X and W, and pursues a partial dimension reduction of X. Though partial dimension reduction is a very general problem, only very few research results are available when W is continuous. To the best of our knowledge, none can deal with the situation where the reduced lower-dimensional subspace of X varies with W. To address such issue, we in this paper propose a …

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Variable-Dependent Partial Dimension Reduction, Lu Li, Kai Tan, Xuerong Meggie Wen, Zhou Yu Jan 2023

Variable-Dependent Partial Dimension Reduction, Lu Li, Kai Tan, Xuerong Meggie Wen, Zhou Yu

Mathematics and Statistics Faculty Research & Creative Works

Sufficient dimension reduction reduces the dimension of a regression model without loss of information by replacing the original predictor with its lower-dimensional linear combinations. Partial (sufficient) dimension reduction arises when the predictors naturally fall into two sets X and W, and pursues a partial dimension reduction of X. Though partial dimension reduction is a very general problem, only very few research results are available when W is continuous. To the best of our knowledge, none can deal with the situation where the reduced lower-dimensional subspace of X varies with W. To address such issue, we in this paper propose a …

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