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2020

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Articles 1651 - 1680 of 15208

Full-Text Articles in Physical Sciences and Mathematics

Mass Spectrometric Determination Of Retinol In Emirati Population, Israa Samir Mohamed Shawky El-Konaissi Nov 2020

Mass Spectrometric Determination Of Retinol In Emirati Population, Israa Samir Mohamed Shawky El-Konaissi

Theses

This thesis is concerned with analyzing vitamin A deficiency. Vitamin A is crucial for several functions, including vision, growth, and cell differentiation. the main aim is to develop and validate an LC-MS/MS method for the determination of vitamin A in plasma matrix and use the new method for the determination of vitamin A levels in the obese Emirati population. Methods: A positive ion electrospray ionisation (ESI) LC-MS/MS method was used in the Multiple Reaction Monitoring (MRM) mode for quantification. It involved i) LC-MS/MS, ii) a guard column together with C18 Ascentis Express F5 column iii) Internal standard, 25-Hydroxyvitamin D3 (6, …


Development Of Supramolecular Multicomponent Chromophores Towards Photoluminescence Switches, Rukayat Shola Bojesomo Nov 2020

Development Of Supramolecular Multicomponent Chromophores Towards Photoluminescence Switches, Rukayat Shola Bojesomo

Theses

A new fluorescent dye (4PBZC) comprises of coumarin (C), piperazine (P), and benzimidazole (BZ) was designed, prepared, and complexed to cucurbit[7]uril (CB7) to detect carnosol (CAR), an anti-breast cancer drug, in sub-nanomolar concentrations utilizing the supramolecular indicator displacement assay (IDA) strategy, the CB7-assisted pKa shift and the CB7-retarded photoinduced electron transfer (PET) process. The host−guest complexation was confirmed by UV−visible absorption, fluorescence, and proton NMR spectroscopy, which confirm binding to 4PBZC via the BZ moiety. Also, CB7 preferentially binds the indicator dye via the protonated BZ residue compared to the neutral BZ one, demonstrated by a higher binding …


Synthesis, Characterization, Electronic Structure Of Biocl/Biobr/Rgo Ternary Heterojunction And Its Photocatalytic Activities, Salama Yousef Alismaail Nov 2020

Synthesis, Characterization, Electronic Structure Of Biocl/Biobr/Rgo Ternary Heterojunction And Its Photocatalytic Activities, Salama Yousef Alismaail

Theses

Solar energy is free, most abundant among all renewable energy sources. Energy from the sun reaches the earth surface at a rate of 1.2 X 105 TW by far, exceeding the current world energy consumption of 17 TW (1TW = 1012 J/s). Accordingly, development of visible light driven photocatalysts is of considerable interest in clean and renewable energy, as well as in wastewater treatment.

In that context, BiOCl and BiOBr and three different mole ratio composites were prepared, characterized using UV-vis DRS, PXRD, BET, SEM, and EDX and their photocatalytic activity for the photoreduction of 4-NA was evaluated. …


Sharp Contrasts In Observed And Modeled Crevasse Patterns At Greenland’S Marine Terminating Glaciers, Ellyn M. Enderlin, Timothy C. Bartholomaus Nov 2020

Sharp Contrasts In Observed And Modeled Crevasse Patterns At Greenland’S Marine Terminating Glaciers, Ellyn M. Enderlin, Timothy C. Bartholomaus

Geosciences Faculty Publications and Presentations

Crevasses are affected by and affect both the stresses and the surface mass balance of glaciers. These effects are brought on through potentially important controls on meltwater routing, glacier viscosity, and iceberg calving, yet there are few direct observations of crevasse sizes and locations to inform our understanding of these interactions. Here we extract depth estimates for the visible portion of crevasses from high-resolution surface elevation observations for 52 644 crevasses from 19 Greenland glaciers. We then compare our observed depths with those calculated using two popular models that assume crevasse depths are functions of local stresses: the Nye and …


Yet Another Possible Explanation Of Egyptian Fractions: Motivated By Fairness, Olga Kosheleva, Vladik Kreinovich Nov 2020

Yet Another Possible Explanation Of Egyptian Fractions: Motivated By Fairness, Olga Kosheleva, Vladik Kreinovich

Departmental Technical Reports (CS)

Ancient Egyptians represented fractions as sums of inverses of natural numbers, and they made sure that all these natural numbers are different. The representation as a sum of inverses makes some sense: it is known to lead to an optimal solution to the problem of dividing bread between workers, a problem often described in the Egyptian papyri. However, this does not explain why the corresponding natural numbers should be all different: some representations with the same natural number repeated several times lead to the same smallest number of cuts as the representations that the ancient Egyptians actually used. In this …


Estimation Of The Removal Of Chiral Pharmaceutical Drugs From Domestic Wastewater Using Uplc-Ms/Ms, Mohammed Khaled Mohammed Al Tabaji Nov 2020

Estimation Of The Removal Of Chiral Pharmaceutical Drugs From Domestic Wastewater Using Uplc-Ms/Ms, Mohammed Khaled Mohammed Al Tabaji

Theses

This thesis is concerned with the estimation of the removal of chiral pharmaceutical compounds (PCs) from domestic wastewater in Al Ain using UPLC-MS/MS. PCs are classified into many classes such as hormones, antibiotics, analgesics, cosmetic products, ꞵ blockers, and anti-inflammatory drugs. PCs do not have a guideline to describe their concentrations in treated domestic wastewater. Additionally, there is a very high demand for using PCs around the world, which results in their discharge to wastewater at relatively high masses, which could be harmful to the environment. Furthermore, very limited work has been done to estimate the removal of chiral PCs. …


Mass Spectrometric Determination Of Retinol In Emirati Population, Israa Samir Mohamed Shawky El-Konaissi Nov 2020

Mass Spectrometric Determination Of Retinol In Emirati Population, Israa Samir Mohamed Shawky El-Konaissi

Theses

This thesis is concerned with analyzing vitamin A deficiency. Vitamin A is crucial for several functions, including vision, growth, and cell differentiation. the main aim is to develop and validate an LC-MS/MS method for the determination of vitamin A in plasma matrix and use the new method for the determination of vitamin A levels in the obese Emirati population. Methods: A positive ion electrospray ionisation (ESI) LC-MS/MS method was used in the Multiple Reaction Monitoring (MRM) mode for quantification. It involved i) LC-MS/MS, ii) a guard column together with C18 Ascentis Express F5 column iii) Internal standard, 25-Hydroxyvitamin D3 (6, …


An Exploratory Study Of General Aviation Visual To Instrument Meteorological Condition Contextual Factors, James Harry Hartman Iii Nov 2020

An Exploratory Study Of General Aviation Visual To Instrument Meteorological Condition Contextual Factors, James Harry Hartman Iii

Doctoral Dissertations and Master's Theses

The purpose of this dissertation was to bridge the existing literature gap of outdated contextual factor (CF) research through examination and determination of current General Aviation (GA) Title 14 Code of Federal Regulations (CFR) Part 91 visual flight rules (VFR)-into-instrument meteorological condition (IMC) contextual factors. Contextual factors are a multifaceted arrangement of pertinent events or occurrences contributing to pilot accidents in weather-related decision-making errors. A total of 46 contextual factors were identified and examined from the reviewed research literature. The study examined and determined the presence of the 46 contextual factors, frequencies, and manifestations in the GA VFR-into-IMC Aviation Accident …


A Natural Formalization Of Changing-One's-Mind Leads To Square Root Of "Not" And To Complex-Valued Fuzzy Logic, Olga Kosheleva, Vladik Kreinovich Nov 2020

A Natural Formalization Of Changing-One's-Mind Leads To Square Root Of "Not" And To Complex-Valued Fuzzy Logic, Olga Kosheleva, Vladik Kreinovich

Departmental Technical Reports (CS)

We show that a natural formalization of the process of changing one's mind leads to such seemingly non-intuitive ideas as square root of "not" and complex-valued fuzzy degrees.


Perceptions And Misperceptions Of Smartphone Use: Applying The Social Norms Approach, John Mcalaney, Mohamed Basel Almourad, Georgina Powell, Raian Ali Nov 2020

Perceptions And Misperceptions Of Smartphone Use: Applying The Social Norms Approach, John Mcalaney, Mohamed Basel Almourad, Georgina Powell, Raian Ali

All Works

© 2020 by the authors. Licensee MDPI, Basel, Switzerland. The social norms approach is an established technique to bring about behaviour change through challenging misperceptions of peer behaviour. This approach is limited by a reliance on self-report and a lack of interactivity with the target population. At the same time, excessive use of digital devices, known as digital addiction, has been recognized as an emergent issue. There is potential to apply the social norms approach to digital addiction and, in doing so, address some of the limitations of the social norms field. In this study, we trialled a social norms …


Deep-Learning-Based App Sensitive Behavior Surveillance For Android Powered Cyber-Physical Systems, Haoyu Ma, Jianwen Tian, Kefan Qiu, David Lo, Debin Gao, Daoyuan Wu, Chunfu Jia, Thar Baker Nov 2020

Deep-Learning-Based App Sensitive Behavior Surveillance For Android Powered Cyber-Physical Systems, Haoyu Ma, Jianwen Tian, Kefan Qiu, David Lo, Debin Gao, Daoyuan Wu, Chunfu Jia, Thar Baker

Research Collection School Of Computing and Information Systems

Android as an operating system is now increasingly being adopted in industrial information systems, especially with Cyber-Physical Systems (CPS). This also puts Android devices onto the front line of handling security-related data and conducting sensitive behaviors, which could be misused by the increasing number of polymorphic and metamorphic malicous applications targeting the platform. The existence of such malware threats therefore call for more accurate identification and surveillance of sensitive Android app behaviors, which is essential to the security of CPS and IoT devices powered by Android. Nevertheless, achieving dynamic app behavior monitoring and identification on real CPS powered by Android …


Microbiological, Physicochemical, And Immunological Analysis Of A Commercial Cashew Nut-Based Yogurt, Christopher P. Mattison, Kayanush Aryana, Kristen Clermont, Eric Prestenburg, Steven W. Lloyd, Casey .. Grimm, Richard L. Wasserman Nov 2020

Microbiological, Physicochemical, And Immunological Analysis Of A Commercial Cashew Nut-Based Yogurt, Christopher P. Mattison, Kayanush Aryana, Kristen Clermont, Eric Prestenburg, Steven W. Lloyd, Casey .. Grimm, Richard L. Wasserman

Faculty Publications

Nut-based milks and yogurts are gaining popularity, but may not offer the same benefits as dairy yogurts to consumers. Cashew nuts often cause severe allergic reactions, and cashew nut allergens are stable to several types of processing. To compare its characteristics to dairy yogurt and characterize the effects of fermentation on the Ana o 1-3 cashew nut allergens, a commercial yogurt made from cashew nuts (Cashewgurt) was evaluated for microbiological, physiochemical, and immunological properties. Average counts for lactobacilli and Streptococcus thermophilus were greater than 10 million colony forming units per milliliter, indicating the capacity to provide a health benefit. Cashewgurt …


Reducing Paper Usage Through Monthly Printing Reports: A Case Study From The College Of The Holy Cross, Office Of Sustainability Nov 2020

Reducing Paper Usage Through Monthly Printing Reports: A Case Study From The College Of The Holy Cross, Office Of Sustainability

Office of Sustainability

This case study outlines the project goals, implementation, and results of a reporting initiative aimed to reduce waste on a small, liberal arts college campus.


Toward The Standardization Of Mesoscale Meteorological Networks, Christopher Fiebrich, Kevin Brinson, Rezaul Mahmood, Stuart Foster, Megan Schargorodski, Nathan L. Edwards, Christopher A. Redmond, Jennie R. Atkins, Jeffrey Andresen, Xiaomao Lin Nov 2020

Toward The Standardization Of Mesoscale Meteorological Networks, Christopher Fiebrich, Kevin Brinson, Rezaul Mahmood, Stuart Foster, Megan Schargorodski, Nathan L. Edwards, Christopher A. Redmond, Jennie R. Atkins, Jeffrey Andresen, Xiaomao Lin

School of Natural Resources: Faculty Publications

Although they share many common qualities in design and operation, mesonetworks across the United States were established independently and organically over the last several decades. In numerous instances, the unique ways each network matured and developed new protocols has led to important lessons learned. These experiences have been shared in informal ways among various network operators over the years to promote reliable operation. As existing networks begin to introduce new sensors and technologies, and as new networks come online, there is a common need for guidance on best practices. This paper aims to formally provide recommendations to improve and harmonize …


Analogy Between Thermodynamic Phase Transitions And Creeping Flows In Rectangular Cavities, Miron Kaufman, Petru S. Fodor Nov 2020

Analogy Between Thermodynamic Phase Transitions And Creeping Flows In Rectangular Cavities, Miron Kaufman, Petru S. Fodor

Physics Faculty Publications

© 2020, MDPI AG. All rights reserved. An analogy is found between the streamline function corresponding to Stokes flows in rectangular cavities and the thermodynamics of phase transitions and critical points. In a rectangular cavity flow, with no-slip boundary conditions at the walls, the corners are fixed points. The corners defined by a stationary and a moving wall, are found to be analogous to a thermodynamic first-order transition point. In contrast, the corners defined by two stationary walls correspond to thermodynamic critical points. Here, flow structures, also known as Moffatt eddies, form and act as stagnation regions where mixing is …


The Importance Of Organic Content To Fractal Floc Properties In Estuarine Surface Waters, Insights From Video, Lisst, And Pump Sampling: Supporting Data, Kelsey A. Fall, Grace M. Massey, Carl T. Friedrichs Nov 2020

The Importance Of Organic Content To Fractal Floc Properties In Estuarine Surface Waters, Insights From Video, Lisst, And Pump Sampling: Supporting Data, Kelsey A. Fall, Grace M. Massey, Carl T. Friedrichs

Data

The linked folders and associated data files contain the observations utilized in Fall, K.A., Friedrichs, C.T., Massey, G.M., Bowers, D.G., and Smith, S.J. (2021). The importance of organic content to fractal floc properties in estuarine surface waters: Insights from video, LISST, and pump sampling. JGR Oceans.

The file “Description of Data Files.pdf” outlines the content of the ten data folders, each of which is associated with a data set collected on an individual one-day cruise in the York River estuary.


A Statistical Learning Regression Model Utilized To Determine Predictive Factors Of Social Distancing During Covid-19 Pandemic, Timothy A. Smith, Albert J. Boquet, Matthew V. Chin Nov 2020

A Statistical Learning Regression Model Utilized To Determine Predictive Factors Of Social Distancing During Covid-19 Pandemic, Timothy A. Smith, Albert J. Boquet, Matthew V. Chin

Publications

In an application of the mathematical theory of statistics, predictive regression modelling can be used to determine if there is a trend to predict the response variable of social distancing in terms of multiple predictor input “predictor” variables. In this study the social distancing is measured as the percentage reduction in average mobility by GPS records, and the mathematical results obtained are interpreted to determine what factors drive that response. This study was done on county level data from the state of Florida during the COVID-19 pandemic, and it is found that the most deterministic predictors are county population density …


2020 November - Tennessee Monthly Climate Report, Tennessee Climate Office, East Tennessee State University Nov 2020

2020 November - Tennessee Monthly Climate Report, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Monthly Report

No abstract provided.


Increasing The Bioavailability Of Poorly Soluble Anti-Cancer Prodrugs Through Encapsulation In Platinum Based Nanocages, Salim Cesar Lutfallah Nov 2020

Increasing The Bioavailability Of Poorly Soluble Anti-Cancer Prodrugs Through Encapsulation In Platinum Based Nanocages, Salim Cesar Lutfallah

Honors Theses

No abstract provided.


Ion Pairing Versus Solvation Of Dinitrobenzene Anions In Room-Temperature Ionic Liquids (Rtils): Vibrational Signatures Of Rtil–Substrate Interactions, Abderrahman Atifi, Piotr J. Mak, Michael D. Ryan Nov 2020

Ion Pairing Versus Solvation Of Dinitrobenzene Anions In Room-Temperature Ionic Liquids (Rtils): Vibrational Signatures Of Rtil–Substrate Interactions, Abderrahman Atifi, Piotr J. Mak, Michael D. Ryan

Chemistry Faculty Research and Publications

The mechanism of solvation of ions by ionic liquids is more complex than solvation in most molecular solvents as the ionic liquid itself provides the counter ion. Solvation and ion pairing of anionic substrates in room-temperature ionic liquids (RTILs) were investigated using resonance Raman spectroscopy and DFT calculations. The purpose of this study was to differentiate between the formation of discrete cation/anion structures and a double-layer cloud of counter ions without specific atomic interactions between the ionic species. In acetonitrile/RTIL mixtures, the radical anion and dianion of dinitrobenzene (DNB) are stabilized by RTILs through solvation and ion pairing. The formation …


Impact Of Concept-Based Mathematics Instructional Strategies On Seventh Grade Student Achievement, Katherine Annette Lawley Ellsworth Nov 2020

Impact Of Concept-Based Mathematics Instructional Strategies On Seventh Grade Student Achievement, Katherine Annette Lawley Ellsworth

Doctoral Dissertations and Projects

In a nation with declining enrollment in college math courses, it is important to examine how mathematics is being taught in the K-12 education system and to identify best practices. The purpose of this study was to examine the impact concept-based instructional strategies has on middle school student achievement in mathematics when integrated into the traditional mathematics curriculum. Participants included 424 seventh grade students from two middle schools. Students Measures of Academic Progress (MAP) Fall-to-Winter data 2018 prior to implementation was used a covariate and Fall-to-Winter data 2019 data during the implementation of concept-based instructional strategies integrated into the traditional …


Nicotine In Tobacco Product Aerosols: 'It's Deja Vu All Over Again', Anna K. Duell, James F. Pankow, David H. Peyton Nov 2020

Nicotine In Tobacco Product Aerosols: 'It's Deja Vu All Over Again', Anna K. Duell, James F. Pankow, David H. Peyton

Chemistry Faculty Publications and Presentations

Introduction: The distribution of nicotine among its free-base (fb) and protonated forms in aerosolised nicotine affects inhalability. It has been manipulated in tobacco smoke and now in electronic cigarettes by the use of acids to de-freebase nicotine and form ‘nicotine salts’.

Methods: Measurements on electronic cigarette fluids (e-liquids) were carried out to determine (1) the fraction of nicotine in the free-base form (α fb) and (2) the levels of organic acid(s) and nicotine. Samples included JUUL ‘pods’, ‘look-a-like/knock-off’ pods and some bottled ‘nicotine salt’ and ‘non-salt’ e-liquids.

Results: α fb= 0.12 ±0.01 at 40°C (≈ 37°C) for 10 JUUL products, …


Extending The Functional Subnetwork Approach To A Generalized Linear Integrate-And-Fire Neuron Model, Nicholas Szczecinski, Roger Quinn, Alexander J. Hunt Nov 2020

Extending The Functional Subnetwork Approach To A Generalized Linear Integrate-And-Fire Neuron Model, Nicholas Szczecinski, Roger Quinn, Alexander J. Hunt

Mechanical and Materials Engineering Faculty Publications and Presentations

Engineering neural networks to perform specific tasks often represents a monumental challenge in determining network architecture and parameter values. In this work, we extend our previously-developed method for tuning networks of non-spiking neurons, the “Functional subnetwork approach” (FSA), to the tuning of networks composed of spiking neurons. This extension enables the direct assembly and tuning of networks of spiking neurons and synapses based on the network’s intended function, without the use of global optimization ormachine learning. To extend the FSA, we show that the dynamics of a generalized linear integrate and fire (GLIF) neuronmodel have fundamental similarities to those of …


Cost-Sensitive Deep Forest For Price Prediction, Chao Ma, Zhenbing Liu, Zhiguang Cao, Wen Song, Jie Zhang, Weiliang Zeng Nov 2020

Cost-Sensitive Deep Forest For Price Prediction, Chao Ma, Zhenbing Liu, Zhiguang Cao, Wen Song, Jie Zhang, Weiliang Zeng

Research Collection School Of Computing and Information Systems

For many real-world applications, predicting a price range is more practical and desirable than predicting a concrete value. In this case, price prediction can be regarded as a classification problem. Although deep forest is recognized as the best solution to many classification problems, a crucial issue limits its direct application to price prediction, i.e., it treated all the misclassifications equally no matter how far away they are from the real classes, since their impacts on the accuracy are the same. This is unreasonable to price prediction as the misclassification should be as close to the real price range as possible …


Multi-User Verifiable Searchable Symmetric Encryption For Cloud Storage, Xueqiao Liu, Guomin Yang, Guomin Yang Nov 2020

Multi-User Verifiable Searchable Symmetric Encryption For Cloud Storage, Xueqiao Liu, Guomin Yang, Guomin Yang

Research Collection School Of Computing and Information Systems

In a cloud data storage system, symmetric key encryption is usually used to encrypt files due to its high efficiency. In order allow the untrusted/semi-trusted cloud storage server to perform searching over encrypted data while maintaining data confidentiality, searchable symmetric encryption (SSE) has been proposed. In a typical SSE scheme, a users stores encrypted files on a cloud storage server and later can retrieve the encrypted files containing specific keywords. The basic security requirement of SSE is that the cloud server learns no information about the files or the keywords during the searching process. Some SSE schemes also offer additional …


A Tripartite Model Of Trust In Facebook: Acceptance Of Information Personalization, Privacy Concern, And Privacy Literacy, Sonny Rosenthal, Ole-Christian Wasenden, Gorm-Andreas Gronnevet, Rich Ling Nov 2020

A Tripartite Model Of Trust In Facebook: Acceptance Of Information Personalization, Privacy Concern, And Privacy Literacy, Sonny Rosenthal, Ole-Christian Wasenden, Gorm-Andreas Gronnevet, Rich Ling

Research Collection College of Integrative Studies

This study draws on the mental accounting perspective and a tripartite model of trust to explain why users trust Facebook. We argue that trust in Facebook is related to (1) trust in companies that collect personal data, (2) acceptance of information personalization, (3) low privacy concern, and (4) low privacy literacy. Further, we argue that privacy literacy amplifies the relationship between privacy concern and the other factors. This is because, among individuals with high privacy literacy, privacy concern is especially diagnostic of the potential harms of a loss of privacy. These arguments align broadly with theorizations about factors influencing privacy-related …


Exploring And Evaluating Attributes, Values, And Structures For Entity Alignment, Zhiyuan Liu, Yixin Cao, Liangming Pan, Juanzi Li, Zhiyuan Liu, Tat-Seng Chua Nov 2020

Exploring And Evaluating Attributes, Values, And Structures For Entity Alignment, Zhiyuan Liu, Yixin Cao, Liangming Pan, Juanzi Li, Zhiyuan Liu, Tat-Seng Chua

Research Collection School Of Computing and Information Systems

Entity alignment (EA) aims at building a unified Knowledge Graph (KG) of rich content by linking the equivalent entities from various KGs. GNN-based EA methods present promising performance by modeling the KG structure defined by relation triples. However, attribute triples can also provide crucial alignment signal but have not been well explored yet. In this paper, we propose to utilize an attributed value encoder and partition the KG into subgraphs to model the various types of attribute triples efficiently. Besides, the performances of current EA methods are overestimated because of the name-bias of existing EA datasets. To make an objective …


Security Analysis Of Permission Re-Delegation Vulnerabilities In Android Apps, Biniam Fisseha Demissie, Mariano Ceccato, Lwin Khin Shar Nov 2020

Security Analysis Of Permission Re-Delegation Vulnerabilities In Android Apps, Biniam Fisseha Demissie, Mariano Ceccato, Lwin Khin Shar

Research Collection School Of Computing and Information Systems

The Android platform facilitates reuse of app func- tionalities by allowing an app to request an action from another app through inter-process communication mechanism. This fea- ture is one of the reasons for the popularity of Android, but it also poses security risks to end users because malicious, unprivileged apps could exploit this feature to make privileged apps perform privileged actions on behalf of them.

In our journal paper [4], we investigate the hybrid use of program analysis, genetic algorithm based test generation, natu- ral language processing, machine learning techniques for precise detection of permission re-delegation vulnerabilities in Android apps. …


Semi-Analytical Model For Design And Analysis Of On-Orbit Servicing Architecture, Koki Ho, Hai Wang, Paul A. De Trempe, Tristan Sarton Du Jonchay, Kento Tomita Nov 2020

Semi-Analytical Model For Design And Analysis Of On-Orbit Servicing Architecture, Koki Ho, Hai Wang, Paul A. De Trempe, Tristan Sarton Du Jonchay, Kento Tomita

Research Collection School Of Computing and Information Systems

Robotic on-orbit servicing (OOS) is expected to be a key technology and concept for future sustainable space exploration. This paper develops a novel semi-analytical model for OOS system analysis, responding to the growing needs and ongoing trend of robotic OOS. An OOS infrastructure system is considered whose goal is to provide responsive services to the random failures of a set of customer modular satellites distributed in space (e.g., at the geosynchronous orbit). The considered OOS architecture comprises a servicer that travels and provides module-replacement services to the customer satellites, an on-orbit depot to store the spares, and a series of …


A Geospatial Analytics Approach To Delineate Trade Areas For Quick Service Restaurants (Qsr) In Singapore, Hui Ting Lim Nov 2020

A Geospatial Analytics Approach To Delineate Trade Areas For Quick Service Restaurants (Qsr) In Singapore, Hui Ting Lim

Research Collection School Of Computing and Information Systems

According to Huff, trade area is defined as “a geographically delineated region containing potential customers for whom there exists a probability greater than zero of their purchasing a given class of products or services offered for sale by a particular firm or by a particular agglomeration of firms”. Several methods to delineate a store trade area have been proposed over the years. For drive-time or travel distance analysis method, the trade area is delineated according to how far or how long the customers are willing to travel to patronise the store. Another commonly used method is the Huff Model which …