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Durability Of Carbon/Conducting Polymer Composite Supported Pt Catalysts Prepared By Supercritical Carbon Dioxide Deposition, Gamze Bozkurt, Fulya Memi̇oğlu, Ayşe Bayrakçeken Yurtcan

Turkish Journal of Chemistry

Polypyrrole (PPy)/carbon (C) composites were synthesized by oxidative chemical polymerization and used as support material for Pt nanoparticles. PPy/C supported Pt nanoparticles were prepared by using a promising catalyst preparation method, supercritical carbon dioxide (scCO$_{2})$ deposition. The prepared materials were characterized by using BET, TGA, XRD, and TEM techniques. Cyclic voltammetry was used in order to determine the electrocatalytic activity of the prepared catalyst for hydrogen oxidation and oxygen reduction reactions that occur in proton exchange membrane fuel cells (PEMFCs). The Pt loading obtained over the composite material was around 10{\%}. TEM results showed highly dispersed and small nanoparticles over …

Synthetic Protocols On 6$H$-Benzo[$C$]Chromen-6-Ones: A Review, Ofentse Mazimba

Turkish Journal of Chemistry

6$H$-Benzo[$c$]chromen-6-ones serve as core structures of secondary metabolites and are of considerable pharmacological importance. Natural sources produce limited quantities, hence the need for synthetic procedures for 6$H$-benzo[$c$]chromen-6-ones, which are herein reviewed. The literature describes protocols such as the Suzuki coupling reactions for the synthesis of biaryl, which then undergoes lactonization, reactions of 3-formylcoumarin (chromenones) with 1,3-bis(silylenol ethers), radical mediated cyclization of arylbenzoates, metal or base catalyzed cyclization of phenyl-2-halobenzoates and 2-halobenzyloxyphenols, and benzoic acid coupling with benzoquinone using electrophilic metal-based catalyst. The efficient and simple procedures are those involving the reactions of Michael acceptor (chromenones and chalcones) with 1,3- and …

Board Member Perceptions Of Small Nonprofit Organization Effectiveness, Laura L. Maurer

Journal of Social, Behavioral, and Health Sciences

In contemporary American society, the nonprofit board is accountable for ensuring that an organization has sufficient resources to carry out its mission. Filling the gap between demands for services and the resources to meet them is often a struggle for small nonprofit organizations, a problem of nonprofit organization effectiveness. I conducted a hermeneutic phenomenological study that examined how board members of small local nonprofits in the focal community perceived nonprofit organization effectiveness. A review of the literature revealed that nonprofit organization effectiveness involved the action of contributing to the organization and the motivation behind the action, both of which were …

Efficient Generalized Inverse For Solving Simultaneous Linear Equations, S. Kadiam Bose, D. T. Nguyen

Civil & Environmental Engineering Faculty Publications

Solving large scale system of Simultaneous Linear Equations (SLE) has been (and continue to be) a major challenging problem for many real-world engineering and science applications. Solving SLE with singular coefficient matrices arises from various engineering and sciences applications [1]-[6]. In this paper, efficient numerical procedures for finding the generalized (or pseudo) inverse of a general (square/rectangle, symmetrical/unsymmetrical, non-singular/singular) matrix and solving systems of Simultaneous Linear Equations (SLE) are formulated and explained. The developed procedures and its associated computer software (under MATLAB [7] computer environment) have been based on "special Cholesky factorization schemes" (for a singular matrix). Test matrices from …

New Frontiers In Chemical Energy And Environmental Engineering, Srinath Suranani, Sandeep Kumar, Sundergopal Sridhar

Civil & Environmental Engineering Faculty Publications

(First paragraph) Energy is one of the major building blocks of modern society. Industries are attributed to be the main source of environmental pollution. The problems associated with the energy and environment have now become the subject of international debate. Engineers play vital role in devising environmental pollution mitigating techniques and developing sustainable energy technologies.

Using Topic Modelling Algorithms For Hierarchical Activity Discovery, Eoin Rogers, John D. Kelleher, Robert J. Ross

Conference papers

Activity discovery is the unsupervised process of discovering patterns in data produced from sensor networks that are monitoring the behaviour of human subjects. Improvements in activity discovery may simplify the training of activity recognition models by enabling the automated annotation of datasets and also the construction of systems that can detect and highlight deviations from normal behaviour. With this in mind, we propose an approach to activity discovery based on topic modelling techniques, and evaluate it on a dataset that mimics complex, interleaved sensor data in the real world. We also propose a means for discovering hierarchies of aggregated activities …

Java Computer Animation For Effective Learning Of The Cholesky Algorithm With Transportation Engineering Applications, Ivan Makohon, Duc T. Nguyen, Mecit Cetin

Civil & Environmental Engineering Faculty Publications

In this paper, the well-known Cholesky Algorithm (for solving simultaneous linear equations, or SLE) is re-visited, with the ultimate goal of developing a simple, user-friendly, attractive, and useful Java Visualization and Animation Graphical User Inter-face (GUI) software as an additional teaching tool for students to learn the Cholesky factorization in a step-by-step fashion with computer voice and animation. A demo video of the Cholesky Decomposition (or factorization) animation and result can be viewed online from the website: http://www.lions.odu.edu/~imako001/cholesky/demo/index.html. The software tool developed from this work can be used for both students and their instructors not only to master this technical …

Kicm: A Knowledge-Intensive Context Model, Fredrick Mtenzi, Denis Lupiana

Conference papers

A context model plays a significant role in developing context-aware architectures and consequently on realizing context-awareness, which is important in today's dynamic computing environments. These architectures monitor and analyse their environments to enable context-aware applications to effortlessly and appropriately respond to users' computing needs. These applications make the use of computing devices intuitive and less intrusive. A context model is an abstract and simplified representation of the real world, where the users and their computing devices interact. It is through a context model that knowledge about the real world can be represented in and reasoned by a context-aware architecture. This …

Using Icicle Trees To Encode The Hierarchical Structure Of Source Code, Ivan Bacher, Brian Mac Namee, John D. Kelleher

Conference papers

This paper presents a study which evaluates the use of a tree visualisation (icicle tree) to encode the hierarchical structure of source code. The tree visualisation was combined with a source code editor in order to function as a compact overview to facilitate the process of comprehending the global structure of a source code document. Results from our study show that pro- viding an overview visualisation led to an increase in accuracy and a decrease in completion time when participants performed counting tasks. However, in locating tasks, the presence of the visualisation led to a decrease in participants’ performance.

Carbon Cycling In Santa Barbara Basin Sediments: A Modeling Study, David J. Burdige, Tomoko Komada, Cédric Magen, Jeffrey P. Chanton

OES Faculty Publications

The primary input of organic matter to almost all marine sediments comes from deposition at the sediment surface. However, in many continental margin settings, reduced carbon can also be added to sediments from below—for example, from “deep” geologic hydrocarbon reservoirs derived from ancient source rocks or from the decomposition of deeply buried gas hydrate deposits. To examine the impact of these two differing reduced carbon inputs on sediment biogeochemistry, a modified reaction-transport model for anoxic marine sediments is described here and applied to data from sediment cores in Santa Barbara Basin to a depth of 4.6 m. Excellent model fits …

Siderophore-Based Microbial Adaptations To Iron Scarcity Across The Eastern Pacific Ocean, Rene M. Boiteau, Daniel R. Mende, Nicholas J. Hawco, Matthew R. Mcilvin, Jessica N. Fitzsimmons, Peter N. Sedwick

OES Faculty Publications

Nearly all iron dissolved in the ocean is complexed by strong organic ligands of unknown composition. The effect of ligand composition on microbial iron acquisition is poorly understood, but amendment experiments using model ligands show they can facilitate or impede iron uptake depending on their identity. Here we show that siderophores, organic compounds synthesized by microbes to facilitate iron uptake, are a dynamic component of the marine ligand pool in the eastern tropical Pacific Ocean. Siderophore concentrations in iron-deficient waters averaged 9 pM, up to fivefold higher than in iron-rich coastal and nutrient-depleted oligotrophic waters, and were dominated by amphibactins, …

Women In Science 2016, Clark Science Center's Summer Research Fellows Program

SURF Abstracts (Women in Science)

Women in Science 2016 summarizes research done by Smith College’s Summer Research Fellowship (SURF) Program participants. Ever since its 1967 start, SURF has been a cornerstone of Smith’s science education. In 2016, 150 students participated in SURF (144 hosted on campus and nearby eld sites), supervised by 56 faculty mentor-advisors drawn from the Clark Science Center and connected to its eighteen science, mathematics, and engineering departments and programs and associated centers and units. At summer’s end, SURF participants were asked to summarize their research experiences for this publication.

An Alignment-Free "Metapeptide" Strategy For Metaproteomic Characterization Of Microbiome Samples Using Shotgun Metagenomic Sequencing, Damon H. May, Emma Timmins-Schiffman, Molly P. Mikan, H. Rodger Harvey, Elhanan Borenstein, Brook L. Nunn, William S. Noble

OES Faculty Publications

In principle, tandem mass spectrometry can be used to detect and quantify the peptides present in a microbiome sample, enabling functional and taxonomic insight into microbiome metabolic activity. However, the phylogenetic diversity constituting a particular microbiome is often unknown, and many of the organisms present may not have assembled genomes. In ocean microbiome samples, with particularly diverse and uncultured bacterial communities, it is difficult to construct protein databases that contain the bulk of the peptides in the sample without losing detection sensitivity due to the overwhelming number of candidate peptides for each tandem mass spectrum. We describe a method for …

The Contribution Of Marine Aggregate-Associated Bacteria To The Accumulation Of Pathogenic Bacteria In Oysters: An Agent-Based Model, Andrew M. Kramer, J. Evan Ward, Fred C. Dobbs, Melissa L. Pierce

OES Faculty Publications

Bivalves process large volumes of water, leading to their accumulation of bacteria, including potential human pathogens (e.g., vibrios). These bacteria are captured at low efficiencies when freely suspended in the water column, but they also attach to marine aggregates, which are captured with near 100% efficiency. For this reason, and because they are often enriched with heterotrophic bacteria, marine aggregates have been hypothesized to function as important transporters of bacteria into bivalves. The relative contribution of aggregates and unattached bacteria to the accumulation of these cells, however, is unknown. We developed an agent-based model to simulate accumulation of vibrio-type bacteria …

A Highly Sensitive Underwater Video System For Use In Turbid Aquaculture Ponds, Chin-Chang Hung, Shih-Chieh Tsao, Kuo-Hao Huang, Hsu-Kunag Chang, Fred C. Dobbs

OES Faculty Publications

The turbid, low-light waters characteristic of aquaculture ponds have made it difficult or impossible for previous video cameras to provide clear imagery of the ponds' benthic habitat. We developed a highly sensitive, underwater video system (UVS) for this particular application and tested it in shrimp ponds having turbidities typical of those in southern Taiwan. The system's high-quality video stream and images, together with its camera capacity (up to nine cameras), permit in situ observations of shrimp feeding behavior, shrimp size and internal anatomy, and organic matter residues on pond sediments. The UVS can operate continuously and be focused remotely, a …

Dragon Kings Of The Deep Sea: Marine Particles Deviate Markedly From The Common Number-Size Spectrum, Alexander B. Bochdansky, Melissa A. Clouse, Gerhard J. Herndl

OES Faculty Publications

Particles are the major vector for the transfer of carbon from the upper ocean to the deep sea. However, little is known about their abundance, composition and role at depths greater than 2000 m. We present the first number-size spectrum of bathy-and abyssopelagic particles to a depth of 5500 m based on surveys performed with a custom-made holographic microscope. The particle spectrum was unusual in that particles of several millimetres in length were almost 100 times more abundant than expected from the number spectrum of smaller particles, thereby meeting the definition of "dragon kings." Marine snow particles overwhelmingly contributed to …

Dynamics Of Plume-Triple Junction Interaction: Results From A Series Of Three-Dimensional Numerical Models And Implications For The Formation Of Oceanic Plateaus, Mladen Dordevic, Jennifer Georgen

OES Faculty Publications

Mantle plumes rising in the vicinity of mid-ocean ridges often generate anomalies in melt production and seafloor depth. This study investigates the dynamical interactions between a mantle plume and a ridge-ridge-ridge triple junction, using a parameter space approach and a suite of steady state, three-dimensional finite element numerical models. The top domain boundary is composed of three diverging plates, with each assigned half-spreading rates with respect to a fixed triple junction point. The bottom boundary is kept at a constant temperature of 1350°C except where a two-dimensional, Gaussian-shaped thermal anomaly simulating a plume is imposed. Models vary plume diameter, plume …

Effects Of Temperature, Irradiance And Pco2 On The Growth And Nitrogen Utilization Of Prorocentrum Donghaiense, Zhangxi Hu, Margaret R. Mulholland, Ning Xu, Shunshan Duan

OES Faculty Publications

Environmental factors such as temp erature, irradiance, and nitrogen (N) supply affect the growth of Prorocentrum donghaiense, but the interactive effects of these physical factors and the effects of atmospheric CO₂ (pCO₂) on growth and N uptake have not been examined. We compared growth kinetics of P. donghaiense grown on 4 different N substrates (nitrate [NO₃ -], ammonium [NH₄ +], urea, and glutamic acid [glu]) with respect to temperature, irradiance, and pCO₂. Temperature (15 to 30°C) had a positive effect on growth (max. growth rates: 0.17 to 0.65 d …

Gorenstein Projective (Pre)Covers, Michael J. Fox

College of Graduate Studies: Theses & Dissertations

The existence of the Gorenstein projective precovers is one of the main open problems in Gorenstein Homological algebra. We give sufficient conditions in order for the class of Gorenstein projective complexes to be special precovering in the category of complexes of R-modules Ch(R). More precisely, we prove that if every complex in Ch(R) has a special Gorenstein flat cover, every Gorenstein projective complex is Gorenstein flat, and every Gorenstein flat complex has finite Goenstein projective dimension, then the class of Gorenstein projective complexes, GP(C), is special precovering in Ch(R).

Remedial Education Programs And Student Success: Perceptions Of Faculty And Administrators At Hbcus, Tenora J. Simonez

College of Graduate Studies: Theses & Dissertations

ABSTRACT

The purpose of this study was to examine factors that contributed to student success in remedial education as perceived by faculty members and administrators at one public HBCU in the University System of Georgia. The five specific areas that contributed to student success and were identified for review were administrative factors, curricula and instructional models, academic support services, importance of placement tests, and the impact of financial issues. Each of these areas was represented in literature regarding the histories of remedial education programs and HBCUs, recent federal and state admissions and fiscal changes, and instructional best practices of remedial …

Horyzonty Współczesnego Zarządzania, Marcin Żemigała

Monografie/Monographs

Książka, opracowana z okazji jubileuszu 70-lecia Pana Prof. Jerzego Bogdanienki. Zgodnie

z jego szerokimi zainteresowaniami badawczymi zatytułowano ją „Horyzonty

współczesnego zarządzania”. Trzydziestu jeden Autorów zechciało podarować

nam swe teksty, które próbują zarysować właśnie owe horyzonty.

Semi-Automatic Identification Of Synonyms In Structured Knowledge Representations, Thomas C. Taylor

Theses

Synonym support is an important aspect of querying knowledge bases, but current approaches to generating such support is difficult and error-prone. Automating the process of identifying synonyms in structured knowledge representations is therefore an important pursuit. This thesis presents an ensemble approach that incorporates several methods and knowledge sources heretofore used individually. A case study shows that the approach performs better than individual methods, and that it may be used to reduce efforts to identify synonyms.

The Study Of Cybersecurity Algorithms From Traditional Computing To The Internet Of Things, Daniel Davis

Theses

A progressive approach to teach students how to develop and deploy cybersecurity algorithms across a wide range of heterogeneous computing devices is proposed. Data confidentiality and data integrity can be ensured when sensitive information is transferred between various types of devices over insecure communication channels by using cybersecurity algorithms. A step-by-step procedure to teach students cybersecurity algorithms on devices ranging from personal computers to devices deployed in the Internet of Things ecosystem is needed. We develop four learning modules that offer students the opportunity to explore commonly utilized cybersecurity algorithms across several heterogeneous devices. Students are able to utilize our …

Second Order Sliding Mode Control Using Nonlinear Dynamic Sliding Manifold : A Lyapunov Approach, Bhargav Chava

Theses

Second order Sliding Mode Control (2-SMC) algorithms require knowledge of derivative of sliding variable, which is to be implemented using 2-SM differentiators. The use of 2-Sliding Mode differentiators causes loss of accuracy. Hence, the approach known as nonlinear dynamic sliding manifold (NDSM) approach is used to design a 2-SM control algorithm without the knowledge of derivative of sliding variable. The main contribution of the thesis is proof of finite time convergence of 2-SMC using NDSM approach by Lyapunov function technique. Also an adaptive 2-SM control law is proposed for perturbed systems with unknown boundaries using NDSM approach to avoid overestimation …

Philosophizing About God And Nature : Connections And Divisions In The Writings Of Isaac Newton, Joshua Riddle

Theses

For several decades, scholars have argued about the relationship between Isaac Newton’s works in science (or natural philosophy), “chymistry,” religion, and theology. Of particular interest has been how his natural philosophy and religion/theology related to each other. Some scholars claim a significant connection between them, even claiming they are part of a “seamless unity” in Newton’s thinking. Other, more skeptical, scholars call for a localized approach to his writings. By entering into this debate and analyzing many of Newton’s manuscripts, I argue that Newton held onto significant disciplinary distinctions in his writings, but also was willing to make small connections …

Heat Deposition During Turbulence Distorted Laser Irradiation, William Vaden Dent Iii

Theses

Realistically modeled heat deposition by a laser source under a variety of turbulent conditions generated from the classic Kolmogorov model is presented. Predicted heat deposition data is created from solutions to the differential heat flow equation and for representative example turbulence distorted waveforms.

Towards A Science Of Security Games, Thanh Hong Nguyen, Debarun Kar, Matthew Brown, Arunesh Sinha, Albert Xin Jiang, Milind Tambe

Research Collection School Of Computing and Information Systems

Security is a critical concern around the world. In many domains from counter-terrorism to sustainability, limited security resources prevent full security coverage at all times; instead, these limited resources must be scheduled, while simultaneously taking into account different target priorities, the responses of the adversaries to the security posture and potential uncertainty over adversary types.Computational game theory can help design such security schedules. Indeed, casting the problem as a Bayesian Stackelberg game, we have developed new algorithms that are now deployed over multiple years in multiple applications for security scheduling. These applications are leading to real-world use-inspired research in the …

Demo: Profiling Power Utilization Behaviours Of Smartwatch Applications, Joseph Joo Keng Chan, Lingxiao Jiang, Rajesh Krishna Balan, Youngki Lee, Archan Misra

Research Collection School Of Computing and Information Systems

Smartwatches complement the main mobile phone and are able to profile user-activity as well as provide links, updates and notifications with work or personal utilities (e.g. Email, Social Media, Messaging etc.). Although very promising, smartwatches are still limited by low battery life. This is due to the small size of the battery as well as the need to continuously perform sensing. Battery drain issues by apps as well as the system are a common complaint by users. Improved tools for power analysis and profiling of smartwatch apps can help both developers (by providing a platform for pre-release analysis) and users …

Demo: Sensing Gamers' Emotions Using Physiological Sensors, Sinh Huynh, Rajesh Krishna Balan, Youngki Lee

Research Collection School Of Computing and Information Systems

Understanding emotions of gamers can benefit game designers in various ways. How gamers feel while they playing a game can be treated as valuable user feedback to improve the development process of that game. Sensing player emotions also enables game designers to create adaptive game that can adjust itself to provide best gaming experience based on player emotions. However, how to effectively evaluate emotions of gamers is still an open research challenge. Two common techniques to evaluate emotional state are using self-assessments such as questionnaires or interviews, and to recognize expressed emotions by analyzing videos or images of facial expression, …

Powerforecaster: Predicting Power Impact Of Mobile Sensing Applications At Pre-Installation Time, Chulhong Min, Youngki Lee, Chungkuk Yoo, Seungwoo Kang, Inseok Hwang, Junehwa Song

Research Collection School Of Computing and Information Systems

Today's smartphone application (hereinafter 'app') markets miss a key piece of information, power consumption of apps. This causes a severe problem for continuous sensing apps as they consume significant power without users' awareness. Users have no choice but to repeatedly install one app after another and experience their power use. To break such an exhaustive cycle, we propose PowerForecaster, a system that provides users with power use of sensing apps at pre-installation time. Such advanced power estimation is extremely challenging since the power cost of a sensing app largely varies with users' physical activities and phone use patterns. We observe …