Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons™

Open Access. Powered by Scholars. Published by Universities.®

Discipline
Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 40531 - 40560 of 294410

Full-Text Articles in Physical Sciences and Mathematics

The Characteristics Of Successful Military It Projects: A Cross-Country Empirical Study, Helene Berg, Jonathan D. Ritschel Jul 2023

The Characteristics Of Successful Military It Projects: A Cross-Country Empirical Study, Helene Berg, Jonathan D. Ritschel

Faculty Publications

In the armed forces, successful digitalization is crucial to ensure effective operations. Much of the existing literature on project factors during the planning and execution phases of public IT projects do not focus specifically on military sector projects. Therefore, the paper aims to provide empirical insights into the characteristics of successful military IT projects. Data from such projects in NATO countries and agencies were collected through interviews and project documents. The findings relating to the main variable of interest, “delivery of client benefit,” supported previous findings on IT project performance. Medium-sized projects performed better than small and large projects, and …


The Impact Of Covid-19 On The Financial Performance Of Largest Teaching Hospitals, Tiffany Champagne-Langabeer, James R Langabeer Jul 2023

The Impact Of Covid-19 On The Financial Performance Of Largest Teaching Hospitals, Tiffany Champagne-Langabeer, James R Langabeer

Faculty, Staff and Student Publications

The COVID-19 pandemic disrupted hospital operations. Anecdotal evidence suggests financial performance likewise suffered, yet little empirical research supports this claim. This study aimed to explore the impact of the pandemic on the financial performance of the most prominent academic hospitals in the United States. Data from the 115 largest major teaching hospitals in the United States were extracted from the American Hospital Directory for three years (2019-2021). We hypothesized that the year and region would moderate the relationship between a hospital's return on assets (financial performance) and specific operational variables. We found evidence through descriptive statistics and multivariate moderated regressions …


Noise Analysis Of The Indian Pulsar Timing Array Data Release I, Aman Srivastava, Shantanu Desai, Neel Kolhe, Mayuresh Surnis, Bhal Chandra Joshi, Abhimanyu Susobhanan, Aurélien Chalumeau, Shinnosuke Hisano, Nobleson K, Raghav Girgaonkar Jul 2023

Noise Analysis Of The Indian Pulsar Timing Array Data Release I, Aman Srivastava, Shantanu Desai, Neel Kolhe, Mayuresh Surnis, Bhal Chandra Joshi, Abhimanyu Susobhanan, Aurélien Chalumeau, Shinnosuke Hisano, Nobleson K, Raghav Girgaonkar

Physics & Astronomy Faculty Publications

The Indian Pulsar Timing Array (InPTA) collaboration has recently made its first official data release (DR1) for a sample of 14 pulsars using 3.5 years of uGMRT observations. We present the results of single-pulsar noise analysis for each of these 14 pulsars using the InPTA DR1. For this purpose, we consider white noise, achromatic red noise, dispersion measure (DM) variations, and scattering variations in our analysis. We apply Bayesian model selection to obtain the preferred noise models among these for each pulsar. For PSR J1600−3053, we find no evidence of DM and scattering variations, while for PSR J1909−3744, we find …


Temperature-Pressure Phase Diagram Of Confined Monolayer Water/Ice At First-Principles Accuracy With A Machine-Learning Force Field, Bo Lin, Jian Jiang, Xiao Cheng Zeng, Lei Li Jul 2023

Temperature-Pressure Phase Diagram Of Confined Monolayer Water/Ice At First-Principles Accuracy With A Machine-Learning Force Field, Bo Lin, Jian Jiang, Xiao Cheng Zeng, Lei Li

Department of Chemistry: Faculty Publications

Understanding the phase behaviour of nanoconfined water films is of fundamental importance in broad fields of science and engineering. However, the phase behaviour of the thinnest water film – monolayer water – is still incompletely known. Here, we developed a machine-learning force field (MLFF) at first-principles accuracy to determine the phase diagram of monolayer water/ice in nanoconfinement with hydrophobic walls. We observed the spontaneous formation of two previously unreported high-density ices, namely, zigzag quasi-bilayer ice (ZZ-qBI) and branched-zigzag quasi-bilayer ice (bZZ-qBI). Unlike conventional bilayer ices, few inter-layer hydrogen bonds were observed in both quasi-bilayer ices. Notably, the bZZ-qBI entails a …


Pull-Push Method: A New Approach To Edge-Isoperimetric Problems, Sergei L. Bezrukov, Nikola Kuzmanovski, Jounglag Lim Jul 2023

Pull-Push Method: A New Approach To Edge-Isoperimetric Problems, Sergei L. Bezrukov, Nikola Kuzmanovski, Jounglag Lim

Department of Mathematics: Faculty Publications

We prove a generalization of the Ahlswede-Cai local-global principle. A new technique to handle edge-isoperimetric problems is introduced which we call the pull-push method. Our main result includes all previously published results in this area as special cases with the only exception of the edge-isoperimetric problem for grids. With this we partially answer a question of Harper on local-global principles. We also describe a strategy for further generalization of our results so that the case of grids would be covered, which would completely settle Harper’s question.


First-Principles Simulations Of Attosecond Transient X-Ray Absorption, Min Chen Jul 2023

First-Principles Simulations Of Attosecond Transient X-Ray Absorption, Min Chen

LSU Doctoral Dissertations

The first part of this dissertation presents calculations of the extinction spec- tra of gold-silver/silver-gold core-shell nanospheres. The goal of this projectsis to get a deeper understanding of surface plasmonic resonance in metal nanospheres with core-shell geometry. Here, we used the finite-difference time-domain (FDTD) method and total-field/scattered-field (TFSF) framework to compute the extinction spectra of nanoparticles to determine the geometry of gold-silver/silver-gold core-shell nanoparticles. This supported experimental work on monitoring the growth dynamics of colloidal gold- silver/silver-gold core-shell nanoparticles using in situ second harmonic generation (SHG) and extinction spectroscopy.

The second and main project involved simulating attosecond transient spectra for …


An Extension Of The Complex–Real (C–R) Calculus To The Bicomplex Setting, With Applications, Daniel Alpay, Kamal Diki, Mihaela Vajiac Jul 2023

An Extension Of The Complex–Real (C–R) Calculus To The Bicomplex Setting, With Applications, Daniel Alpay, Kamal Diki, Mihaela Vajiac

Mathematics, Physics, and Computer Science Faculty Articles and Research

In this paper, we extend notions of complex ℂ−ℝ-calculus to the bicomplex setting and compare the bicomplex polyanalytic function theory to the classical complex case. Applications of this theory include two bicomplex least mean square algorithms, which extend classical real and complex least mean square algorithms.


Impact Of Forest Management On Ozark Big-Eared Bat (Corynorhinus Townsendii Ingens) Prey And Foraging Ecology, Gemma L. Marsh Jul 2023

Impact Of Forest Management On Ozark Big-Eared Bat (Corynorhinus Townsendii Ingens) Prey And Foraging Ecology, Gemma L. Marsh

ATU Theses and Dissertations 2021 - Present

Ozark big-eared bats (Corynorhinus townsendii ingens) are an endangered species of bat found only in Oklahoma and Arkansas. I conducted a study on the impact of forest management treatments, such as prescribed fire and mechanical thinning, in White Rock Mountain Wildlife Management Area, which is home to a maternity colony of Ozark big-eared bats. My goal was to understand how prescribed fire and mechanical thinning influence Ozark big-eared bat prey and foraging, and therefore be able to provide management recommendations for the habitat of this endangered species. My results indicated that bat prey availability was influenced by forest structure, …


Mitigating Landslide Hazards In Qena Governorate Of Egypt: A Gis-Based Neutrosophic Paprika Approach, Nabil M. Abdelaziz, Safa Al-Saeed Jul 2023

Mitigating Landslide Hazards In Qena Governorate Of Egypt: A Gis-Based Neutrosophic Paprika Approach, Nabil M. Abdelaziz, Safa Al-Saeed

Neutrosophic Systems with Applications

This paper presents a novel approach to landslide susceptibility assessment in the Qena Governorate, Egypt, integrating the neutrosophic Multi-Criteria Decision-Making (MCDM) method, the Potentially All Pairwise RanKings of all possible Alternatives (PAPRIKA), and the ArcGIS weighted overlay technique. The research focuses on the quantification and prioritization of eight criteria: slope, aspect, proximity to road, soil type, proximity to river, land cover, elevation, and Lithology. These factors are evaluated under the uncertainty and indeterminacy of the neutrosophic environment by employing the PAPRIKA method. The results of the analysis are visualized and interpreted using ArcGIS weighted overlay, offering spatially explicit insights into …


Cratonic Basins As Effective Sediment Barriers In Continent‑Scale Sediment Routing Systems Of Paleozoic North America, Andrea L. Stevens Goddard, Olivia G. Thurston, David H. Malone, Patrick L. Mclaughlin, Jack Stewart Jul 2023

Cratonic Basins As Effective Sediment Barriers In Continent‑Scale Sediment Routing Systems Of Paleozoic North America, Andrea L. Stevens Goddard, Olivia G. Thurston, David H. Malone, Patrick L. Mclaughlin, Jack Stewart

Faculty Publications - Geography, Geology, and the Environment

Provenance studies demonstrate the important control of plate boundary mountain building on continental sediment routing systems. Less well understood is if subsidence and uplift in cratons also has the potential to affect the organization of sediment routing systems on continental scales. New detrital zircon provenance data from the Michigan Basin in the Midcontinent of North America preserve evidence of intrabasin provenance heterogeneity in Cambrian, Ordovician, and middle Devonian strata. These results suggest that cratonic basins serve as effective sediment barriers that prevent mixing within and across basins from 10 to 100 s of millions of years. Internal sediment mixing, sorting, …


Meta-Analysis Of United States Seabird Populations Based On Ocean Biodiversity Information System (Obis) Records (1965–2018), Savannah Hartman Jul 2023

Meta-Analysis Of United States Seabird Populations Based On Ocean Biodiversity Information System (Obis) Records (1965–2018), Savannah Hartman

USF Tampa Graduate Theses and Dissertations

Understanding the distribution of organisms is an important priority for society as we live through ecosystem transformations that threaten the well-being of all organisms. I have approached the dynamic and complex issue of studying biodiversity by using open-access seabird data collected along the Americas since the 1960s. I explained how these data have changed over time and space, how certain species populations could have shifted over time, and possible correlations between this potential geographic change and select environmental variables.

In Chapter 2 I evaluated the suitability of the open-access data archive Ocean Biodiversity Information System (OBIS) for supporting detailed inquiry …


Identification Of Unsuccessful Students In General Chemistry, G. Robert Shelton, Joseph M. Simpson, Diana Mason Jul 2023

Identification Of Unsuccessful Students In General Chemistry, G. Robert Shelton, Joseph M. Simpson, Diana Mason

All Faculty Scholarship (Archived)

The Networking for Science Advancement (NSA) team collected data from multiple general chemistry courses at nine universities within a broad geographic setting in a majority-minority US state. Data include diagnostic scores on the Math-Up Skills Test (MUST), quantitative literacy/quantitative reasoning (QL/QR) quiz, along with student demographics, and overall course grades. From these data the team determined how automaticity skills in procedural arithmetic and quantitative literacy and reasoning can be used to predict success in lower-division chemistry courses. By expanding this dataset, we extended our investigations to discover what characterizes successful and unsuccessful students in general chemistry, first and second semesters …


Predictability Of The Must (Math-Up Skills Test), Diana Mason, G. Robert Shelton Jul 2023

Predictability Of The Must (Math-Up Skills Test), Diana Mason, G. Robert Shelton

All Faculty Scholarship (Archived)

In the USA for the most part, completion of a first-semester general chemistry (Chem I) course lays the foundation deemed necessary for understanding second-semester general chemistry (Chem II) topics. Successful completion of Chem I and II gives students permission to progress to organic chemistry I (O-Chem). A series of studies undertaken by the NSA (Networking for Science Advancement) Texas team began in 2016. Texas is one of five majority-minority states in the USA and hosts a significant Hispanic population. The purpose of this research line is to evaluate the influence of basic arithmetic automaticity (what students can do without a …


Library Copyright Alliance Principles For Copyright And Artificial Intelligence, Library Copyright Alliance, American Library Association, Association Of Research Libraries Jul 2023

Library Copyright Alliance Principles For Copyright And Artificial Intelligence, Library Copyright Alliance, American Library Association, Association Of Research Libraries

Copyright, Fair Use, Scholarly Communication, etc.

Library Copyright Alliance principles for copyright and artificial intelligence, July 10, 2023.


Holocene Rice Rats (Genus Oryzomys) From The Upper Mississippi River Drainage Basin, Hugh H. Genoways Jul 2023

Holocene Rice Rats (Genus Oryzomys) From The Upper Mississippi River Drainage Basin, Hugh H. Genoways

Zea E-Books Collection

The expansion and collapse of the geographic range of the Texas rice rat (Oryzomys texensis) in the upper Mississippi River drainage basin at the end of the Holocene was a unique event in North American mammals. In a period of about 4000 years with a point of origin near the American Bottom in Illinois, these small rodents extended their geographic range in a straight-line distance of over 950 km to the west into Nebraska and the same distance to the east into Pennsylvania. Then in less than 400 years this range expansion collapsed back to a point where …


Mitigating Landslide Hazards In Qena Governorate Of Egypt: A Gis-Based Neutrosophic Paprika Approach, Nabil M. Abdelaziz, Safa Al-Saeed Jul 2023

Mitigating Landslide Hazards In Qena Governorate Of Egypt: A Gis-Based Neutrosophic Paprika Approach, Nabil M. Abdelaziz, Safa Al-Saeed

Neutrosophic Systems with Applications

This paper presents a novel approach to landslide susceptibility assessment in the Qena Governorate, Egypt, integrating the neutrosophic Multi-Criteria Decision-Making (MCDM) method, the Potentially All Pairwise RanKings of all possible Alternatives (PAPRIKA), and the ArcGIS weighted overlay technique. The research focuses on the quantification and prioritization of eight criteria: slope, aspect, proximity to road, soil type, proximity to river, land cover, elevation, and Lithology. These factors are evaluated under the uncertainty and indeterminacy of the neutrosophic environment by employing the PAPRIKA method. The results of the analysis are visualized and interpreted using ArcGIS weighted overlay, offering spatially explicit insights into …


The Effect Of Heat Treatment And Chemical Treatment On Natural Fibre To The Durability Of Wood Plastic Composites – A Review, Nuratiqah Asyiqin Mohd Nasharudin, Nur Fatihah Sulaiman, Nurul Aziemah Mohammad, Wan Nor Raihan Wan Jaafar, Falah Abu Dr., Siti Norasmah Surip Jul 2023

The Effect Of Heat Treatment And Chemical Treatment On Natural Fibre To The Durability Of Wood Plastic Composites – A Review, Nuratiqah Asyiqin Mohd Nasharudin, Nur Fatihah Sulaiman, Nurul Aziemah Mohammad, Wan Nor Raihan Wan Jaafar, Falah Abu Dr., Siti Norasmah Surip

Journal of Materials Exploration and Findings

The application of WPC is not only limited to indoor applications but has been extended to exterior applications where properties of WPC could compromise during service life. WPC was derived from wood fiber of various sizes to reinforce polymers. Wood fiber has the advantage of a cheaper price, being abundantly available, and ease of processing, however, the critical factor is its hydrophilic nature, where moisture absorption is likely to occur. Thus, treatments for reducing the hydrophilicity of wood fibers are applied. By treatment of wood fiber, the surface impurities were removed, leaving the roughened surface of fibers, thus providing a …


Cationic Divalent Metal Sites (M = Mn, Fe, Co) Operating As Both Nitrene-Transfer Agents And Lewis Acids Toward Mediating The Synthesis Of Three- And Five-Membered N-Heterocycles, Suraj Kumar Sahoo, Brent Harfmann, Lin Ai, Qiuwen Wang, Sudip Mohapatra, Amitava Choudhury, Pericles Stavropoulos Jul 2023

Cationic Divalent Metal Sites (M = Mn, Fe, Co) Operating As Both Nitrene-Transfer Agents And Lewis Acids Toward Mediating The Synthesis Of Three- And Five-Membered N-Heterocycles, Suraj Kumar Sahoo, Brent Harfmann, Lin Ai, Qiuwen Wang, Sudip Mohapatra, Amitava Choudhury, Pericles Stavropoulos

Chemistry Faculty Research & Creative Works

The tripodal compounds [(TMG3trphen)MII-solv](PF6)2 (M = Mn, Fe, Co; solv = MeCN, DMF) and bipodal analogues [(TMG2biphen)MII(NCMe)x](PF6)2 (x = 3 for Mn, Fe; x = 2 for Co) and [(TMG2biphen)MIICl2] have been synthesized with ligands that feature a triaryl- or diarylmethyl-amine framework and superbasic tetramethylguanidinyl residues (TMG). The dicationic M(II) sites mediate catalytic nitrene-transfer reactions between the imidoiodinane PhI═NTs (Ts = tosyl) and a panel of styrenes in MeCN to afford aziridines and low yields of imidazolines (upon …


Re: Approval Letter For The Butte Priority Soils Operable Unit, Superfund Stormwater Operation And Maintenance (O&M); Mountain Con Sw Channel Diversion, Request For Change (Rfc)-Bsb Sitewide-2023-001 (Dated June 29, 2023), Nikia Greene Jul 2023

Re: Approval Letter For The Butte Priority Soils Operable Unit, Superfund Stormwater Operation And Maintenance (O&M); Mountain Con Sw Channel Diversion, Request For Change (Rfc)-Bsb Sitewide-2023-001 (Dated June 29, 2023), Nikia Greene

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Biological Formation Of Ethylene, Robert P. Hausinger, Simahudeen Bathir Jaber Sathik Rifayee, Midhun George Thomas, Shramana Chatterjee, Jian Hu, Christo Christov Jul 2023

Biological Formation Of Ethylene, Robert P. Hausinger, Simahudeen Bathir Jaber Sathik Rifayee, Midhun George Thomas, Shramana Chatterjee, Jian Hu, Christo Christov

Michigan Tech Publications

This review summarizes the structures, biochemical properties, and mechanisms of two major biological sources of ethylene, the ethylene-forming enzyme (EFE) and 1-aminocyclopropane-1-carboxylic acid (ACC) oxidase (ACCO). EFE is found in selected bacteria and fungi where it catalyzes two reactions: (1) the oxygen-dependent conversion of 2-oxoglutarate (2OG) to ethylene plus three molecules of CO2/bicarbonate and (2) the oxidative decarboxylation of 2OG while transforming l-arginine to guanidine and l-Δ1-pyrroline-5-carboxylic acid. ACCO is present in plants where it makes the plant hormone by transforming ACC, O2, and an external reductant to ethylene, HCN, CO2, and water. Despite catalyzing distinct chemical reactions, EFE and …


Asymptotics And Sign Patterns For Coefficients In Expansions Of Habiro Elements, Ankush Goswami, Abhash Kumar Jha, Byungchan Kim, Robert Osburn Jul 2023

Asymptotics And Sign Patterns For Coefficients In Expansions Of Habiro Elements, Ankush Goswami, Abhash Kumar Jha, Byungchan Kim, Robert Osburn

School of Mathematical & Statistical Sciences Faculty Publications

We prove asymptotics and study sign patterns for coefficients in expansions of elements in the Habiro ring which satisfy a strange identity. As an application, we prove asymptotics and discuss positivity for the generalized Fishburn numbers which arise from the Kontsevich–Zagier series associated to the colored Jones polynomial for a family of torus knots. This extends Zagier’s result on asymptotics for the Fishburn numbers.


On Teaching Multi-Criteria Decision Making With A Robot Assistant, Chen Zhang, Hakan Saraoglu, David A. Louton Jul 2023

On Teaching Multi-Criteria Decision Making With A Robot Assistant, Chen Zhang, Hakan Saraoglu, David A. Louton

Information Systems and Analytics Department Faculty Conference Proceedings

We propose a system and method for a robot assistant for teaching multi-attribute decision making (MCDM). Through questions and answers in natural language, the robot assistant learns the user’s preferences on multiple criteria involving a selection decision and makes recommendations using data on each criterion and the learned user preferences. It will include a use-case demonstration where NAO the robot will assist a human in forming a simple portfolio of mutual funds. Presenters will illustrate the architecture of the robot assisted MCDM and describe a method that is extensively used to structure complex decision problems and has been applied to …


Probabilistic Modeling Of North Atlantic Ocean Hurricane Spawn Considering Climate Change, Susmita Bhowmik, Weichiang Pang, Michael Stoner Jul 2023

Probabilistic Modeling Of North Atlantic Ocean Hurricane Spawn Considering Climate Change, Susmita Bhowmik, Weichiang Pang, Michael Stoner

Publications

Hurricanes are a significant natural hazard, which cause significant damage and financial losses in the coastal areas of the United States almost every year. For example, the devastating nature of North Atlantic Ocean (NAO) storms can easily be understood from the 2005 Hurricane Katrina, which was the most damaging NAO storm in modern history, causing more than 1,800 deaths and a financial loss of at least 161.3 billion USD. It has been found that the formations of hurricanes depend heavily on climate conditions, which implies a direct relationship between the changes in climate extremes and the occurrences of hurricanes or …


“I Have Learned That Things Are Different Here”: Understanding The Transitional Challenges With Technology Use After Relocating To The Usa, Prakriti Dumaru, Ankit Shrestha, Rizu Paudel, Arezou Behfar, Hanieh Atashpanjeh, Mahdi Nasrullah Al-Ameen Jul 2023

“I Have Learned That Things Are Different Here”: Understanding The Transitional Challenges With Technology Use After Relocating To The Usa, Prakriti Dumaru, Ankit Shrestha, Rizu Paudel, Arezou Behfar, Hanieh Atashpanjeh, Mahdi Nasrullah Al-Ameen

Computer Science Student Research

In the age of globalization, international students from developing countries (for brevity, we term them as ‘international students’ in this paper, unless otherwise specified) have become an integral part of the U.S. education system. After relocation to the USA, first-generation international students undergo not only societal differences but also experience changes in the technology space – posing unique challenges for them. Our semi-structured interviews with 26 participants who were pursuing education at the time of our study, or had recently graduated informed us of their adaptation to the technology landscape in the USA; our analysis revealed the underlying challenges in …


Towards Improving The Efficacy Of Windows Security Notifier For Apps From Unknown Publishers: The Role Of Rhetoric, Ankit Shrestha, Rizu Paudel, Prakriti Dumaru, Mahdi Nasrullah Al-Ameen Jul 2023

Towards Improving The Efficacy Of Windows Security Notifier For Apps From Unknown Publishers: The Role Of Rhetoric, Ankit Shrestha, Rizu Paudel, Prakriti Dumaru, Mahdi Nasrullah Al-Ameen

Computer Science Student Research

With over 1.4 billion users of Windows 10, it is the most widely used operating system in the world. In Windows, applications from unknown publishers are popular due to mass availability and ease of access. Installing such applications can lead to malware infection, including viruses and ransomware. Therefore, we explored the design of interventions to prevent the users from installing applications from unknown publishers. To this end, we conducted a lab study with nine participants to understand the perceptions and behavior of users toward the designed interventions. Then, we conducted an online study with 256 participants to evaluate the impact …


Platonism, De Re, And (Philosophy Of) Mathematical Practice, Marco Panza Jul 2023

Platonism, De Re, And (Philosophy Of) Mathematical Practice, Marco Panza

MPP Published Research

The chapter advances a reformulation of the classical problem of the nature of mathematical objects (if any), here called “Plato’s problem,” in line with the program of a philosophy of mathematical practice. It then provides a sketch of a platonist solution, following the same perspective. This solution disregards as nonsensical the question of the existence of abstract, and specifically mathematical, objects, by rather focusing on the modalities of our access to them: objects (in general, both concrete and abstract) are regarded as individual contents that we have (or can have) a de re epistemic access to. The question of the …


Study On The Self-Repairing Effect Of Nanoclay In Powder Coatings For Corrosion Protection, Marshall S. Yang, Jinbao Huang, Hui Zhhang, James Noel, Yolanda S. Hedberg, Jian Chen, Ubong Eduok, Ivan Barker, Jeffrey D. Henderson, Chengqian Xian, Haiping Zhang, Jesse Zhu Jul 2023

Study On The Self-Repairing Effect Of Nanoclay In Powder Coatings For Corrosion Protection, Marshall S. Yang, Jinbao Huang, Hui Zhhang, James Noel, Yolanda S. Hedberg, Jian Chen, Ubong Eduok, Ivan Barker, Jeffrey D. Henderson, Chengqian Xian, Haiping Zhang, Jesse Zhu

Chemistry Publications

Powder coatings are a promising, solvent-free alternative to traditional liquid coatings due to the superior corrosion protection they provide. This study investigates the effects of incorporating montmorillonite-based nanoclay additives with different particle sizes into polyester/triglycidyl isocyanurate (polyester/TGIC) powder coatings. The objective is to enhance the corrosion-protective function of the coatings while addressing the limitations of commonly employed epoxy-based coating systems that exhibit inferior UV resistance. The anti-corrosive and surface qualities of the coatings were evaluated via neutral salt spray tests, electrochemical measurements, and surface analytical techniques. Results show that the nanoclay with a larger particle size of 18.38 µm (D50, …


How Do Pedestrians Perceive The Safety, Comfort, And Usefulness Of A Walking Space? An Exploratory Study Of Pedestrian Perception, Amanda Rifqa Marisa, Achmad Hery Fuad Jul 2023

How Do Pedestrians Perceive The Safety, Comfort, And Usefulness Of A Walking Space? An Exploratory Study Of Pedestrian Perception, Amanda Rifqa Marisa, Achmad Hery Fuad

Smart City

Car-oriented development has brought several negative impacts on human quality of life. Therefore, it is necessary to pay more attention to walkability as one of the essential aspects of it, especially in the urban area. In the meantime, most research on walking and walkability still overlooks the role of the pedestrian's perspective in examining walkability. Hence, this research tries to fill the gap in walkability research by exploring the pedestrian perspectives on the safety, comfort, and usefulness of walking space as the three overlapping aspects between walkability and walking needs. This research took context in Suryakencana, Bogor City, Indonesia. To …


Implementation Of An Efficient Bayesian Search For Gravitational-Wave Bursts With Memory In Pulsar Timing Array Data, Jerry Sun, Paul T. Baker, Aaron D. Johnson, Dustin R. Madison, Xavier Siemens Jul 2023

Implementation Of An Efficient Bayesian Search For Gravitational-Wave Bursts With Memory In Pulsar Timing Array Data, Jerry Sun, Paul T. Baker, Aaron D. Johnson, Dustin R. Madison, Xavier Siemens

Pacific Faculty Work

The standard Bayesian technique for searching pulsar timing data for gravitational-wave bursts with memory (BWMs) using Markov Chain Monte Carlo (MCMC) sampling is very computationally expensive to perform. In this paper, we explain the implementation of an efficient Bayesian technique for searching for BWMs. This technique makes use of the fact that the signal model for Earth-term BWMs (BWMs passing over the Earth) is fully factorizable. We estimate that this implementation reduces the computational complexity by a factor of 100. We also demonstrate that this technique gives upper limits consistent with published results using the standard Bayesian technique, and may …


Scope And Mechanistic Studies On The Ruthenium-Catalyzed Multicomponent Deaminative C–H Coupling Reaction Of Phenols With Aldehydes And Enamines For The Formation Of Xanthene And Dioxacyclic Derivatives, Nuwan Asanka Pannilawithana, Mina Son, Donghun Hwang, Mu-Hyun Baik, Chase S. Yi Jul 2023

Scope And Mechanistic Studies On The Ruthenium-Catalyzed Multicomponent Deaminative C–H Coupling Reaction Of Phenols With Aldehydes And Enamines For The Formation Of Xanthene And Dioxacyclic Derivatives, Nuwan Asanka Pannilawithana, Mina Son, Donghun Hwang, Mu-Hyun Baik, Chase S. Yi

Chemistry Faculty Research and Publications

The in situ generated catalytic system from the tetranuclear Ru–H complex [(PCy3)(CO)RuH]4(O)(OH)2 (1) with 3,4,5,6-tetrachloro-1,2-benzoquinone (L1) has been found to mediate a multicomponent deaminative coupling reaction of phenols with aldehydes and enamines to form xanthene products. The multicomponent C–H coupling reaction of phenols with 2-hydroxybenzaldehydes and cyclic enamines efficiently installed the tricyclic 1,3-dioxacin derivatives, while the analogous coupling reaction of phenols with 2-hydroxybenzaldehydes and triethylamine selectively formed bicyclic 1,5-dioxacyclic derivatives. The density functional theory (DFT) calculations established two energetically viable mechanistic pathways for the formation of xanthene products, in which both …