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2024

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Articles 4021 - 4050 of 8178

Full-Text Articles in Physical Sciences and Mathematics

Multimodal Data Fusion And Machine Learning For Advancing Biomedical Applications, Md Inzamam Ul Haque May 2024

Multimodal Data Fusion And Machine Learning For Advancing Biomedical Applications, Md Inzamam Ul Haque

Doctoral Dissertations

This dissertation delves into the intricate landscape of biomedical imaging, examining the transformative potential of data fusion techniques to refine our understanding and diagnosis of health conditions. Daily influxes of diverse biomedical data prompt an exploration into the challenges arising from relying solely on individual imaging modalities. The central premise revolves around the imperative to combine information from varied sources to achieve a holistic comprehension of complex health issues.

The chapters included here contain articles and excerpts from published works. The study unfolds through an examination of four distinct applications of data fusion techniques. It commences with refining clinical task …


Novel Energy Scale Calibration Strategies For The Prospect-Ii Experiment, Xiaobin Lu May 2024

Novel Energy Scale Calibration Strategies For The Prospect-Ii Experiment, Xiaobin Lu

Doctoral Dissertations

Nuclear reactors contributed to the first discovery of the elusive neutrino particle and continue to play a significant role in our understanding of neutrino masses and oscillations. The PROSPECT reactor neutrino experiment, the Precision Reactor Oscillation and SPECTrum Experiment, took data at the High Flux Isotope Reactor (HFIR) at Oak Ridge National Laboratory. This work discusses calibration procedures and the establishment of an energy scale model, and details the development of efficient analysis cuts and subsequent selection cut optimization. The precise energy scale calibration and efficient analysis cuts produced a high quality dataset of neutrino interactions of more than 50,000 …


Experimental Quantum Key Distribution In Turbulent Channels, Kazi Mh Reaz May 2024

Experimental Quantum Key Distribution In Turbulent Channels, Kazi Mh Reaz

Doctoral Dissertations

Quantum Key Distribution (QKD) ensures security by relying on the laws of quantum physics rather than the mathematical intricacy of encryption algorithms. The transmission medium is a critical restricting factor for any quantum communication protocol. Fiber-based optical networks suffer great losses, making quantum communication impossible beyond metropolitan scales. Here free-space quantum communication can be a great alternative for long-distance communication. Even though modern Communications are mostly wireless the atmosphere poses a challenge for QKD. So QKD must be resistant to both atmospheric loss and variations in transmittance. In this thesis we conduct an experiment to strengthen the BB84 protocol's resistance …


Biotinylated Protein Capture And Tween-20 Assisted Exosome Isolations Via Capillary Chanelled Polymer Fiber, Md Khalid Bin Islam May 2024

Biotinylated Protein Capture And Tween-20 Assisted Exosome Isolations Via Capillary Chanelled Polymer Fiber, Md Khalid Bin Islam

All Theses

In the past two decades, Marcus and colleagues have led the advancement of capillary-channeled polymer (C-CP) fiber stationary phases for biomacromolecule separations, including proteins and nanovesicles. These stationary phases offer notable advantages, including low cost ($5/column), straightforward column fabrication, and the capacity for on-column surface modification, enabling high chemical selectivity. This study examines a C-CP fiber modification strategy for capturing target proteins and develops a Tween-20-assisted C-CP-based hydrophobic interaction chromatography (HIC) method for the isolation and quantification of exosomes from human urine.

The quest for higher-throughput and cost-effective protein isolation techniques remains a key focus in a variety of end …


Crystallographic Defects In Weyl Semimetal Laalge, Inseo Kim, Byungkyun Kang, Hyunsoo Kim, Minseok Choi May 2024

Crystallographic Defects In Weyl Semimetal Laalge, Inseo Kim, Byungkyun Kang, Hyunsoo Kim, Minseok Choi

Physics Faculty Research & Creative Works

Crystallographic Defects in a Topological Semimetal Can Result in Charge Doping and Scattering Centers Which May Mask the Exotic Spectroscopic and Transport Properties, respectively. Here, We Investigate the Possible Crystallographic Defects Including Vacancy and Antisite in Weyl Semimetal LaAlGe using Hybrid-Density-Functional Theory Calculations. We Show that a Considerable Concentration of Al- and Ge-Related Defects Naturally Form during Growth Due to their Low Formation Enthalpy. Specifically, Al Can Be Easily Replaced by Ge in the I41md Phase of LaAlGe, Forming the Ge-On-Al Antisite, GeAl. the Counterpart, Al-On-Ge (AlGe), is Also Probable. the Most Abundant Defect GeAl is Donorlike, Effectively Electron Doping, …


Consequences Of The Megafauna Extinction: Changes In Food Web Networks On The Edwards Plateau Across The Pleistocene-Holocene Transition, Quentin A. Smith Jr. May 2024

Consequences Of The Megafauna Extinction: Changes In Food Web Networks On The Edwards Plateau Across The Pleistocene-Holocene Transition, Quentin A. Smith Jr.

School of Biological Sciences: Dissertations, Theses, and Student Research

We are experiencing biodiversity loss due to climate change and human impacts, which is not only harmful to the environment but can also alter the composition of communities and interactions among species. The late Pleistocene experienced a loss of large-bodied mammals which resulted in significant changes in community structure due to changes in body size, diet, and species associations. The impact of these changes on species interactions and community structure across the Pleistocene-Holocene transition remains poorly understood. Using a robust data set of species composition, stable isotopes, body size, and climate variables, we constructed and compared ecological networks of mammal …


Sliding Markov Decision Processes For Dynamic Task Planning On Uncrewed Aerial Vehicles, Trent Wiens May 2024

Sliding Markov Decision Processes For Dynamic Task Planning On Uncrewed Aerial Vehicles, Trent Wiens

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Mission and flight planning problems for uncrewed aircraft systems (UASs) are typically large and complex in space and computational requirements. With enough time and computing resources, some of these problems may be solvable offline and then executed during flight. In dynamic or uncertain environments, however, the mission may require online adaptation and replanning. In this work, we will discuss methods of creating MDPs for online applications, and a method of using a sliding resolution and receding horizon approach to build and solve Markov Decision Processes (MDPs) in practical planing applications for UASs. In this strategy, called a Sliding Markov Decision …


Bidding Strategy For A Wind Power Producer In Us Energy And Reserve Markets, Anne Stratman May 2024

Bidding Strategy For A Wind Power Producer In Us Energy And Reserve Markets, Anne Stratman

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

Wind power is one of the world's fastest-growing renewable energy resources and has expanded quickly within the US electric grid. Currently, wind power producers (WPPs) may sell energy products in US markets but are not allowed to sell reserve products, due to the uncertain and intermittent nature of wind power. However, as wind’s share of the power supply grows, it may eventually be necessary for WPPs to contribute to system-wide reserves. This paper proposes a stochastic optimization model to determine the optimal offer strategy for a WPP that participates in the day-ahead and real-time energy and spinning reserve markets. The …


Seasonal Comparison Of Air Quality Variables And Evaluation Of Carbon Dioxide And Particulate Measurement Period In Classrooms, Daud Nosham May 2024

Seasonal Comparison Of Air Quality Variables And Evaluation Of Carbon Dioxide And Particulate Measurement Period In Classrooms, Daud Nosham

Durham School of Architectural Engineering and Construction: Dissertations, Theses, and Student Research

Indoor air quality and thermal environmental variables were measured in 55 classrooms in the mid-western United States spanning a full academic year. The studied air quality and environmental factors included carbon dioxide, temperature, relative humidity, particle counts, air velocity, formaldehyde, total volatile organic compounds, carbon monoxide, nitrogen dioxide, and ozone.

Carbon dioxide and Particulate matter concentrations were measured for a four-day measurement period. Then one-day, two-day, and four-day occupied time average concentrations were calculated which were then compared statistically to figure out an appropriate measurement period for these air quality variables. Kruskal Wallis test and Wilcoxon test were used to …


Synthesis And Characterization Of Indole-Based Zinc Dipyrrin Photosensitizers, Jean-Pierre Sanza May 2024

Synthesis And Characterization Of Indole-Based Zinc Dipyrrin Photosensitizers, Jean-Pierre Sanza

Electronic Theses and Dissertations

Metal complexes of dipyrromethene (dipyrrins) used as sensitizers in photocatalysis offer a way to harness solar energy in chemical bonds to create new fuels. This offers the dual role of reducing fossil fuel dependence and atmospheric CO2 levels. Traditionally, metal dipyrrin complexes are synthesized using substituted pyrroles, aldehydes, and transition metals. Indoles have a more expanded pi-electron system and their dipyrrin-type complex may exhibit visible light absorption, suggesting that they can act as photosensitizers for CO2 reduction processes. A novel indoledipyrromethene was synthesized using unsubstituted indole and mesitaldehyde. The complex exhibits visible light absorption at 422 nm. Its …


Comparative Analysis Of Surrogate Models For The Dissolution Of Spent Nuclear Fuel, Dayo Awe May 2024

Comparative Analysis Of Surrogate Models For The Dissolution Of Spent Nuclear Fuel, Dayo Awe

Electronic Theses and Dissertations

This thesis presents a comparative analysis of surrogate models for the dissolution of spent nuclear fuel, with a focus on the use of deep learning techniques. The study explores the accuracy and efficiency of different machine learning methods in predicting the dissolution behavior of nuclear waste, and compares them to traditional modeling approaches. The results show that deep learning models can achieve high accuracy in predicting the dissolution rate, while also being computationally efficient. The study also discusses the potential applications of surrogate modeling in the field of nuclear waste management, including the optimization of waste disposal strategies and the …


New Algorithms For The Multiplication Table Problem, Evan Blom May 2024

New Algorithms For The Multiplication Table Problem, Evan Blom

Undergraduate Honors Thesis Collection

In 1955, Paul Erdős initiated the study of a function that counts the number of distinct integers in an (n × n) multiplication table. That is, he studied M(n) = |{i · j, 1 ≤ i, j ≤ n}|. Much research has been done in regards to both asymptotic and exact approximations of M(n) for increasingly large values of n. Recently, Brent et. al. investigated the algorithmic cost in computing this function. Instead of computing M(n) directly, their approach was to compute it incrementally. That is, given M(n−1), they could quickly compute M(n) using another function δ(n) to count the …


Manipulation Of The Magnetic Properties Of Van Der Waals Materials Through External Stimuli, Luis Martinez May 2024

Manipulation Of The Magnetic Properties Of Van Der Waals Materials Through External Stimuli, Luis Martinez

Open Access Theses & Dissertations

A new revolutionary application dependent on the electron spin to carry information with greater efficiency in data storage, transfer, and processing, will rely heavily on 2D magnets and the ability to effectively control their electron spins and engineer their properties. Previously, magnetic thin films were heavily studied to achieve this goal, however, these materials came with pitfalls and lacked naturally occurring 2D magnetism. The recent discovery of intrinsic magnetism in few-layered van der Waals (vdW) magnets has inspired researchers to extensively study them because of the feasibility to exfoliate them down to a monolayer. Due to this dimensionality factor, vdW …


Navigate The World Of Rfid: Diversity, Capabilities, And Constraints Of Readers And Tags, Rachana Pandey May 2024

Navigate The World Of Rfid: Diversity, Capabilities, And Constraints Of Readers And Tags, Rachana Pandey

2024 Spring Honors Capstone Projects

Radio-Frequency Identification (RFID) technology, a method for storing and retrieving data through electromagnetic transmission to an RFID tag, is revolutionizing inventory and asset management in various sectors, including healthcare. This research explores the applications of RFID in a medical setting. It assesses various RFID readers and tags, focusing on their functional capabilities, ranges, and limitations within a medical environment. Employing a comprehensive approach, the study integrates an extensive literature review, comparative analysis, and empirical data from both experimental simulations and real-world healthcare scenarios. The aim is to identify RFID solutions that optimize surgical equipment management, thereby enhancing both operational efficiency …


Depositional Facies And Petrophysical Characterization Of The Leonardian Carbonate (Lower Clear Fork), Tex-Mex, S.E. Field, Central Basin Platform, West Texas, Seyram Nyamasekpor May 2024

Depositional Facies And Petrophysical Characterization Of The Leonardian Carbonate (Lower Clear Fork), Tex-Mex, S.E. Field, Central Basin Platform, West Texas, Seyram Nyamasekpor

Electronic Theses and Dissertations

The Lower Clear Fork from Tex-Mex, S.E. Field on the Central Basin Platform is a typical complex reservoir that displays high heterogeneity in lithological and petrophysical properties. The unit represents a producing reservoir succession of Leonardian platform carbonates deposited in shallow marine water during the Early Permian. The sediment of the Lower Clear Fork is composed of a mixed succession of dolomite interbedded with anhydrite, minor clay minerals, and siliciclastics. The high heterolithic nature of the reservoir makes efficient recovery of hydrocarbons difficult. This situation requires an understanding of the variability in depositional facies in terms of mineralogy, depositional textures …


A Dual-Polarimetric Analysis Of A Large Sample Of Left-Moving Supercells, Ben Schweigert May 2024

A Dual-Polarimetric Analysis Of A Large Sample Of Left-Moving Supercells, Ben Schweigert

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Supercells have been researched extensively since they were first described over 50 years ago. They are prolific severe weather producers, responsible for the most severe hail, severe wind gusts, and tornadoes. These rotating thunderstorms require attention from forecasters to protect life and property from their threats, most effectively done with Doppler radars. While extensive amounts of radar-based investigations have been completed, they focused almost exclusively on right-moving (RM) supercells, resulting in a knowledge gap surrounding their counter-rotating (left-moving, LM) partners. This study works to fill the void by developing a dataset of LM supercells and analyzing the dual-polarimetric features observed …


2024 May - Tennessee Monthly Climate Report, Tennessee Climate Office, East Tennessee State University May 2024

2024 May - Tennessee Monthly Climate Report, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Monthly Report

No abstract provided.


Asteroidal Sets And Dominating Targets In Graphs, Oleksiy Al-Saadi May 2024

Asteroidal Sets And Dominating Targets In Graphs, Oleksiy Al-Saadi

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

The focus of this PhD thesis is on various distance and domination properties in graphs. In particular, we prove strong results about the interactions between asteroidal sets and dominating targets. Our results add to or extend a plethora of results on these properties within the literature. We define the class of strict dominating pair graphs and show structural and algorithmic properties of this class. Notably, we prove that such graphs have diameter 3, 4, or contain an asteroidal quadruple. Then, we design an algorithm to to efficiently recognize chordal hereditary dominating pair graphs. We provide new results that describe the …


A Novel Correction For The Multivariate Ljung-Box Test, Minhao Huang May 2024

A Novel Correction For The Multivariate Ljung-Box Test, Minhao Huang

Computational and Data Sciences (PhD) Dissertations

This research introduces an analytical improvement to the Multivariate Ljung-Box test that addresses significant deviations of the original test from the nominal Type I error rates under almost all scenarios. Prior attempts to mitigate this issue have been directed at modification of the test statistics or correction of the test distribution to achieve precise results in finite samples. In previous studies, focused on designing corrections to the univariate Ljung-Box, a method that specifically adjusts the test rejection region has been the most successful of attaining the best Type I error rates. We adopt the same approach for the more complex, …


Proof-Of-Concept For Converging Beam Small Animal Irradiator, Benjamin Insley May 2024

Proof-Of-Concept For Converging Beam Small Animal Irradiator, Benjamin Insley

Dissertations & Theses (Open Access)

The Monte Carlo particle simulator TOPAS, the multiphysics solver COMSOL., and

several analytical radiation transport methods were employed to perform an in-depth proof-ofconcept

for a high dose rate, high precision converging beam small animal irradiation platform.

In the first aim of this work, a novel carbon nanotube-based compact X-ray tube optimized for

high output and high directionality was designed and characterized. In the second aim, an

optimization algorithm was developed to customize a collimator geometry for this unique Xray

source to simultaneously maximize the irradiator’s intensity and precision. Then, a full

converging beam irradiator apparatus was fit with a multitude …


Using The History Of Statistics To Teach Introductory Statistics, Melissa Hansen May 2024

Using The History Of Statistics To Teach Introductory Statistics, Melissa Hansen

All Graduate Reports and Creative Projects, Fall 2023 to Present

While often taught in high school and required as part of a college degree, statistics classes are sometimes viewed by students as an obstacle rather than a support for their overall goals. One way to increase student engagement in a statistics course is to use the history of statistics. Within the literature review, the advantages to using the history of statistics are discussed as well as the more extensive research on using the history of mathematics in mathematics courses. Included are instructional strategies for using the context around the development of mathematical ideas in math classrooms which can be extended …


Soil Reclamation Strategies In Construction Disturbed Soil, Alexis Koelling May 2024

Soil Reclamation Strategies In Construction Disturbed Soil, Alexis Koelling

All Graduate Reports and Creative Projects, Fall 2023 to Present

The rapid urbanization occurring in arid environments like the Intermountain West region of the U.S. significantly alters soil conditions. Construction of roads, buildings, and other infrastructure leads to the disturbance of soil structure, nutrient depletion, and reduced fertility. This research addresses the need for sustainable soil management practices that may restore soil health post-construction. In this study, the effectiveness of various soil amendments and application methods on specific soil parameters and turfgrass establishment in construction-disturbed soils was evaluated. The study highlights the critical role of soil amendments, particularly municipal solid waste (MSW) compost, in improving soil quality and plant growth. …


Consultation Summary For Proposed Declared Pest Rates 2024/2025, Department Of Primary Industries And Regional Development, Western Australia May 2024

Consultation Summary For Proposed Declared Pest Rates 2024/2025, Department Of Primary Industries And Regional Development, Western Australia

Biosecurity published reports

Before determining a rate, the Minister for Agriculture and Food is required to consult with owners of the land to be rated, as described in the Biosecurity and Agriculture Management (Declared Pest Account) Regulations 2014 (the Regulations).

The annual process for consultation enables the Department of Primary Industries and Regional Development (DPIRD) to gauge landholder perception on the proposed Declared Pest Rate (DPR) in accordance with the Regulations.


Diffusion-Based Negative Sampling On Graphs For Link Prediction, Yuan Fang, Yuan Fang May 2024

Diffusion-Based Negative Sampling On Graphs For Link Prediction, Yuan Fang, Yuan Fang

Research Collection School Of Computing and Information Systems

Link prediction is a fundamental task for graph analysis with important applications on the Web, such as social network analysis and recommendation systems, etc. Modern graph link prediction methods often employ a contrastive approach to learn robust node representations, where negative sampling is pivotal. Typical negative sampling methods aim to retrieve hard examples based on either predefined heuristics or automatic adversarial approaches, which might be inflexible or difficult to control. Furthermore, in the context of link prediction, most previous methods sample negative nodes from existing substructures of the graph, missing out on potentially more optimal samples in the latent space. …


On The Feasibility Of Simple Transformer For Dynamic Graph Modeling, Yuxia Wu, Yuan Fang, Lizi Liao May 2024

On The Feasibility Of Simple Transformer For Dynamic Graph Modeling, Yuxia Wu, Yuan Fang, Lizi Liao

Research Collection School Of Computing and Information Systems

Dynamic graph modeling is crucial for understanding complex structures in web graphs, spanning applications in social networks, recommender systems, and more. Most existing methods primarily emphasize structural dependencies and their temporal changes. However, these approaches often overlook detailed temporal aspects or struggle with long-term dependencies. Furthermore, many solutions overly complicate the process by emphasizing intricate module designs to capture dynamic evolutions. In this work, we harness the strength of the Transformer’s self-attention mechanism, known for adeptly handling long-range dependencies in sequence modeling. Our approach offers a simple Transformer model, called SimpleDyG, tailored for dynamic graph modeling without complex modifications. We …


Swapvid: Integrating Video Viewing And Document Exploration With Direct Manipulation, Taichi Murakami, Kazuyuki Fujita, Kotaro Hara, Kazuki Takashima, Yoshifumi Kitamura May 2024

Swapvid: Integrating Video Viewing And Document Exploration With Direct Manipulation, Taichi Murakami, Kazuyuki Fujita, Kotaro Hara, Kazuki Takashima, Yoshifumi Kitamura

Research Collection School Of Computing and Information Systems

Videos accompanied by documents—document-based videos—enable presenters to share contents beyond videos and audience to use them for detailed content comprehension. However, concurrently exploring multiple channels of information could be taxing. We propose SwapVid, a novel interface for viewing and exploring document-based videos. SwapVid seamlessly integrates a video and a document into a single view and lets the content behaves as both video and a document; it adaptively switches a document-based video to act as a video or a document upon direct manipulation (e.g., scrolling the document, manipulating the video timeline). We conducted a user study with twenty participants, comparing SwapVid …


Dlvs4audio2sheet: Deep Learning-Based Vocal Separation For Audio Into Music Sheet Conversion, Nicole Teo, Zhaoxia Wang, Ezekiel Ghe, Yee Sen Tan, Kevan Oktavio, Alexander Vincent Lewi, Allyne Zhang, Seng-Beng Ho May 2024

Dlvs4audio2sheet: Deep Learning-Based Vocal Separation For Audio Into Music Sheet Conversion, Nicole Teo, Zhaoxia Wang, Ezekiel Ghe, Yee Sen Tan, Kevan Oktavio, Alexander Vincent Lewi, Allyne Zhang, Seng-Beng Ho

Research Collection School Of Computing and Information Systems

While manual transcription tools exist, music enthusiasts, including amateur singers, still encounter challenges when transcribing performances into sheet music. This paper addresses the complex task of translating music audio into music sheets, particularly challenging in the intricate field of choral arrangements where multiple voices intertwine. We propose DLVS4Audio2Sheet, a novel method leveraging advanced deep learning models, Open-Unmix and Band-Split Recurrent Neural Networks (BSRNN), for vocal separation. DLVS4Audio2Sheet segments choral audio into individual vocal sections and selects the optimal model for further processing, aiming towards audio into music sheet conversion. We evaluate DLVS4Audio2Sheet’s performance using these deep learning algorithms and assess …


Algorithms For Canvas-Based Attention Scheduling With Resizing, Yigong Hu, Ila Gokarn, Shengzhong Liu, Archan Misra, Tarek Adbelzaher May 2024

Algorithms For Canvas-Based Attention Scheduling With Resizing, Yigong Hu, Ila Gokarn, Shengzhong Liu, Archan Misra, Tarek Adbelzaher

Research Collection School Of Computing and Information Systems

Canvas-based attention scheduling was recently pro-posed to improve the efficiency of real-time machine perception systems. This framework introduces a notion of focus locales, referring to those areas where the attention of the inference system should “allocate its attention”. Data from these locales (e.g., parts of the input video frames containing objects of interest) are packed together into a smaller canvas frame which is processed by the downstream machine learning algorithm. Compared with processing the entire input data frame, this practice saves resources while maintaining inference quality. Previous work was limited to a simplified solution where the focus locales are quantized …


Large Language Model Powered Agents In The Web, Yang Deng, An Zhang, Yankai Lin, Xu Chen, Ji-Rong Wen, Tat-Seng Chua May 2024

Large Language Model Powered Agents In The Web, Yang Deng, An Zhang, Yankai Lin, Xu Chen, Ji-Rong Wen, Tat-Seng Chua

Research Collection School Of Computing and Information Systems

Web applications serve as vital interfaces for users to access information, perform various tasks, and engage with content. Traditional web designs have predominantly focused on user interfaces and static experiences. With the advent of large language models (LLMs), there’s a paradigm shift as we integrate LLM-powered agents into these platforms. These agents bring forth crucial human capabilities like memory and planning to make them behave like humans in completing various tasks, effectively enhancing user engagement and offering tailored interactions in web applications. In this tutorial, we delve into the cutting-edge techniques of LLM-powered agents across various web applications, such as …


Analysis And Numerical Simulation Of Tumor Growth Models, Daniel Acosta Soba May 2024

Analysis And Numerical Simulation Of Tumor Growth Models, Daniel Acosta Soba

Masters Theses and Doctoral Dissertations

In this dissertation we focus on the numerical analysis of tumor growth models. Due to the difficulty of developing physically meaningful approximations of such models, we divide the main problem into more simple pieces of work that are addressed in the different chapters. First, in Chapter 2 we present a new upwind discontinuous Galerkin (DG) scheme for the convective Cahn–Hilliard model with degenerate mobility which preserves the pointwise bounds and prevents non-physical spurious oscillations. These ideas are based on a well-suited piecewise constant approximation of convection equations. The proposed numerical scheme is contrasted with other approaches in several numerical experiments. …