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Full-Text Articles in Physical Sciences and Mathematics

Coastal Resources Management Training Needs Assessment: Strategies And Opportunities, Kevin O'Brien, Claudette Robey, Wendy Kellogg, Michael Tevesz Dec 2015

Coastal Resources Management Training Needs Assessment: Strategies And Opportunities, Kevin O'Brien, Claudette Robey, Wendy Kellogg, Michael Tevesz

Michael J. Tevesz

The Old Woman Creek National Estuarine Research Reserve (OWC), Ohio Department of Natural Resources-Coastal Management Program (ODNRCMP), and Ohio Sea Grant College Program engaged the Great Lakes Environmental Finance Center (GLEFC) to aid them in developing a coastal resources management training initiative for Ohio coastal decision-makers. Coastal decision-maker professionals are expected to formulate effective strategies and apply interdisciplinary approaches to solving problems and policy issues that affect the environments of coastal regions. There are a number of professionals in a variety of occupations who make decisions regarding coastal and environmental policy issues. These individuals include those within the coastal resources …

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Silica-Bound Copper(Ii) Triazacyclononane As A Phosphate Esterase: Effect Of Linker Length And Surface Hydrophobicity, Brett Bodsgard, Robert Clark, Anthony Ehrbar, Judith Burstyn Dec 2015

Silica-Bound Copper(Ii) Triazacyclononane As A Phosphate Esterase: Effect Of Linker Length And Surface Hydrophobicity, Brett Bodsgard, Robert Clark, Anthony Ehrbar, Judith Burstyn

Robert Clark

A series of silica-bound Cu(II) triazacyclononane materials was prepared to study the effect of linker length and surface hydrophobicity on the hydrolysis of phosphate esters. The general synthetic approach for these heterogeneous reagents was rhodium-catalyzed hydrosilation between an alkenyl-modified triazacyclononane and hydride-modified silica followed by metallation with a Cu(II) salt. Elemental analysis confirmed that organic functionalization of the silica gel was successful and provided an estimate of the surface concentration of triazacyclononane. EPR spectra were consistent with square pyramidal Cu(II), indicating that Cu(II) ions were bound to the immobilized macrocycles. The hydrolytic efficacies of these heterogeneous reagents were tested with …

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Magnet Traveling Through A Conducting Pipe: A Variation On The Analytical Approach, Benjamin Irvine, Matthew Kemnetz, Asim Gangopadhyaya, Thomas Ruubel Dec 2015

Magnet Traveling Through A Conducting Pipe: A Variation On The Analytical Approach, Benjamin Irvine, Matthew Kemnetz, Asim Gangopadhyaya, Thomas Ruubel

Asim Gangopadhyaya

We present an analytical study of magnetic damping. In particular, we investigate the dynamics of a cylindrical neodymium magnet as it moves through a conducting tube. Owing to the very high degree of uniformity of the magnetization for neodymium magnets, we are able to provide completely analytical results for the electromotive force generated in the pipe and the consequent retarding force. Our analytical expressions are shown to have excellent agreement with experimental observations.

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Noncentral Potentials And Spherical Harmonics Using Supersymmetry And Shape Invariance, Ranabir Dutt, Asim Gangopadhyaya, Uday Sukhatne Dec 2015

Noncentral Potentials And Spherical Harmonics Using Supersymmetry And Shape Invariance, Ranabir Dutt, Asim Gangopadhyaya, Uday Sukhatne

Asim Gangopadhyaya

It is shown that the operator methods of supersymmetric quantum mechanics and the concept of shape invariance can profitably be used to derive properties of spherical harmonics in a simple way. The same operator techniques can also be applied to several problems with noncentral vector and scalar potentials. As examples, we analyze the bound state spectra of an electron in a Coulomb plus an Aharonov – Bohm field and/or in the magnetic field of a Dirac monopole.

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Isomer Distribution Of Succinylcyclohexenyl, Acetylcyclohexenyl And Acetylcyclopentenyl Enamines, A. Cook, Sarah Folk Dec 2015

Isomer Distribution Of Succinylcyclohexenyl, Acetylcyclohexenyl And Acetylcyclopentenyl Enamines, A. Cook, Sarah Folk

A. Gilbert Cook

The isomeric distributions of some cyclohexenyl enamines substituted by succinyl or acetyl groups at either the 2- or 6-positions are reported as are the isomeric distributions of similarly substituted cyclopentenyl enamines. Correlation between the C-13 NMR chemical shifts in these enamines and isomer distribution is shown. Density functional molecular modeling is used to demonstrate resonance and electrostatic effects on isomeric distributions.

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Supersymmetric Quantum Mechanics And Solvable Models, Asim Gangopadhyaya, Jonathan Bougie, Jeffrey Mallow, C. Rasinariu Dec 2015

Supersymmetric Quantum Mechanics And Solvable Models, Asim Gangopadhyaya, Jonathan Bougie, Jeffrey Mallow, C. Rasinariu

Asim Gangopadhyaya

We review solvable models within the framework of supersymmetric quantum mechanics (SUSYQM). In SUSYQM, the shape invariance condition insures solvability of quantum mechanical problems. We review shape invariance and its connection to a consequent potential algebra. The additive shape invariance condition is specified by a difference-differential equation; we show that this equation is equivalent to an infinite set of partial differential equations. Solving these equations, we show that the known list of h-independent superpotentials is complete. We then describe how these equations could be extended to include superpotentials that do depend on h.

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Web-Based Intelligent Multimedia Tutoring For High Stakes Achievement Tests, Ivon Arroyo Dec 2015

Web-Based Intelligent Multimedia Tutoring For High Stakes Achievement Tests, Ivon Arroyo

Ivon Arroyo

We describe Wayang Outpost, a web-based ITS for the Math section of the Scholastic Aptitude Test (SAT). It has several distinctive features: help with multimedia animations and sound, problems embedded in narrative and fantasy contexts, alternative teaching strategies for students of different mental rotation abilities and memory retrieval speeds. Our work on adding intelligence for adaptivity is described. Evaluations prove that students learn with the tutor, but learning depends on the interaction of teaching strategies and cognitive abilities. A new adaptive tutor is being built based on evaluation results; surveys results and students’ log files analyses.

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Land-Use Pattern, Urbanization, And Deer–Vehicle Collisions In Alabama, Anwar Hussain, James Armstrong, David Brown, John Hogland Dec 2015

Land-Use Pattern, Urbanization, And Deer–Vehicle Collisions In Alabama, Anwar Hussain, James Armstrong, David Brown, John Hogland

David C. Brown

With the rise in deer–vehicle collisions across the United States, the associated costs also have risen. Increasingly, however, researchers are learning that these collisions are not a random phenomena but follow a systematic pattern. Building on this insight, we explored the role of county characteristics in influencing the pattern and incidence of white-tailed deer- (Odocoileus virginianus) related auto collisions. Using county level data from 1994 to 2003 in Alabama, we tested several data models with the above mentioned factors …

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Comment On "Ideal Capacitor Circuits And Energy Conservation" By K. Mita And M. Boufaida [Am. J. Phys. 67 (8), 737-739 (1999)], Asim Gangopadhyaya, Jeffrey Mallow Dec 2015

Comment On "Ideal Capacitor Circuits And Energy Conservation" By K. Mita And M. Boufaida [Am. J. Phys. 67 (8), 737-739 (1999)], Asim Gangopadhyaya, Jeffrey Mallow

Asim Gangopadhyaya

No abstract provided.

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Impact Of Heme Reconstitution On The Spectroscopic Properties And Dna Binding Activity Of The H82a Variant Of The Carbon Monoxide-Sensing Heme Transcription Factor, Cooa, Rachel Troester, Robert Clark Dec 2015

Impact Of Heme Reconstitution On The Spectroscopic Properties And Dna Binding Activity Of The H82a Variant Of The Carbon Monoxide-Sensing Heme Transcription Factor, Cooa, Rachel Troester, Robert Clark

Robert Clark

CooA is a gas-sensing heme protein that regulates the expression of genes responsible for growth by carbon monoxide (CO) in several bacteria. CO binding to the CooA heme groups results in an allosteric conformation change that initiates the protein’s DNA binding function. All known CooA homologs have a conserved histidine residue that i) acts as the proximal heme ligand and ii) istrans to CO. Together with the results from mutagenesis studies, this observation suggests the presence of a proximal histidine ligand is required for CooA’s DNA-binding activity. However, since mutants lacking this His have been observed to lose heme …

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Semiclassical Approach To Quantum-Mechanical Problems With Broken Supersymmetry, Ranabir Dutt, Asim Gangopadhyaya, Avinash Khare, A. Pagnamenta, Uday Sukhatne Dec 2015

Semiclassical Approach To Quantum-Mechanical Problems With Broken Supersymmetry, Ranabir Dutt, Asim Gangopadhyaya, Avinash Khare, A. Pagnamenta, Uday Sukhatne

Asim Gangopadhyaya

The semiclassical WKB approximation method is reexamined in the context of nonrelativistic quantum-mechanical bound-state problems with broken supersymmetry (SUSY). This gives rise to an alternative quantization condition (denoted by BSWKB) which is different from the standard WKB formula and also different from the previously studied supersymmetric (SWKB) formula for unbroken SUSY. It is shown that to leading order in ħ, the BSWKB condition yields exact energy eigenvalues for shape-invariant potentials with broken SUSY (harmonic oscillator, Pöschl-Teller I and II) which are known to be analytically solvable. Further, we show explicitly that the higher-order corrections to these energy eigenvalues, up to …

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Reasoning With Design Rationale, Janet Burge, David Brown Dec 2015

Reasoning With Design Rationale, Janet Burge, David Brown

David C. Brown

Design Rationale (DR) consists of the decisions made during the design process and the reasons behind them. Because it offers more than just a “snapshot” of the final design decisions, DR is invaluable as an aid for revising, maintaining, documenting, evaluating, and learning the design. Much work has been performed on how DR can be captured and represented but not as much on how it can be used. In this paper, we investigate the use of DR by building InfoRat, a system that inferences over a design’s rationale in order to detect inconsistencies and to assess the impact of changes.

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Renormalization Group Equations In Broken Supersymmetric Theories Using Superspace Methods, Asim Gangopadhyaya, Darwin Chang Dec 2015

Renormalization Group Equations In Broken Supersymmetric Theories Using Superspace Methods, Asim Gangopadhyaya, Darwin Chang

Asim Gangopadhyaya

We apply the superfield method with the spurion technique to derive the renormalization-group equations in broken supersymmetric theories. We point out some possible ambiguities in this procedure and show that it is in general necessary to express the supersymmetry-breaking terms in explicit D-type form. We also found that it is possible to construct broken supersymmetric theories where some of the symmetry-breaking parameters do not receive any infinite renormalization.

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Tradeoffs Between Energy And Security In Wireless Networks, Fernando Colón Osorio, Emmanuel Agu, Kerry Mckay Dec 2015

Tradeoffs Between Energy And Security In Wireless Networks, Fernando Colón Osorio, Emmanuel Agu, Kerry Mckay

Emmanuel O. Agu

In recent years, several researchers have studied the vulnerabilities present in the encryption protocols and authentication mechanisms associated with 802.11-based networks. This research has led to the creation of protocol extensions and replacement proposals such as WPA, 802.11i, and 802.1X. In addition, Denial of Service attacks that can be launched against 802.11-based networks, with relative ease and impunity, have been studied. Simultaneously, researchers studying the limitations of wireless networks have turned their attention to one of the inherent limitation of wireless devices, namely, power consumption. Research in this area has been focused in understanding the impact of the network interface …

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Comment On ‘‘The Hidden Symmetry For A Quantum System With An Infinitely Deep Square-Well Potential By Shi-Hai Dong And Zhong-Qi Ma [Am. J. Phys. 70 (5) 520-521 (2002)], Asim Gangopadhyaya, Jeffrey Mallow Dec 2015

Comment On ‘‘The Hidden Symmetry For A Quantum System With An Infinitely Deep Square-Well Potential By Shi-Hai Dong And Zhong-Qi Ma [Am. J. Phys. 70 (5) 520-521 (2002)], Asim Gangopadhyaya, Jeffrey Mallow

Asim Gangopadhyaya

No abstract provided.

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Gas-Binding Studies Of The Carbon Monoxide Sensor, Cooa, Joshua Wagoner, Lindsey Dillingham, Robert Clark Dec 2015

Gas-Binding Studies Of The Carbon Monoxide Sensor, Cooa, Joshua Wagoner, Lindsey Dillingham, Robert Clark

Robert Clark

CooA is a carbon monoxide-sensing (CO-sensing) heme protein transcription factor that regulates gene activation in several bacteria and is a convenient model for studying analogous proteins in the human body. The goal of this study is to understand the specificity and mechanism of gas binding of CooA. To accomplish this, wild type CooA and selected protein variants were purified and then reacted with different diatomic gas molecules. The resulting species were characterized by UV-Visible and fluorescence spectroscopy.

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Preliminary Design Of A High Tc Superconducting Persistent Mode Current Switch, Christopher Hawley, Dominic Cuiuri, Steve Gower Dec 2015

Preliminary Design Of A High Tc Superconducting Persistent Mode Current Switch, Christopher Hawley, Dominic Cuiuri, Steve Gower

Dominic Cuiuri

Persistent Mode Current Switches (PMCS) are made from coils of superconductor that in theory will provide zero conduction losses when closed. By causing a section of the superconductor to leave its superconducting state and become resistive, the switch is effectively opened. There are currently 3 methods to open a PMCS; 1) applying heat, 2) applying a magnetic field or 3) application of current above the critical current (Ic) of the tape. The first two methods are not suitable for power applications as the switching time is too slow. Recent work at the University of Wollongong and in literature has shown …

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Characterizing The Performance And Behaviors Of Runners Using Twitter, Qian He, Emmanuel Agu, Diane Strong, Bengisu Tulu, Peder Pedersen Dec 2015

Characterizing The Performance And Behaviors Of Runners Using Twitter, Qian He, Emmanuel Agu, Diane Strong, Bengisu Tulu, Peder Pedersen

Emmanuel O. Agu

Running is a popular physical activity that improves physical and mental wellbeing. Unfortunately, up-to- date information about runners’ performance and psychological wellbeing is limited. Many questions remain unanswered, such as how far and how fast runners typically run, their preferred running times and frequencies, how long new runners persist before dropping out, and what factors cause runners to quit. Without hard data, establishing patterns of runner behavior and mitigating the challenges they face are difficult. Collecting data manually from large numbers of runners for research studies is costly and time consuming. Emerging Social Networking Services (SNS) and fitness tracking devices …

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Mutagenesis Studies To Investigate Ligand Binding To The Carbon Monoxide-Sensing Heme Protein, Cooa, From Carboxydothermus Hydrogenoformans, Laura Wagoner, Josh Wagoner, Thomas Goyne, Robert Clark Dec 2015

Mutagenesis Studies To Investigate Ligand Binding To The Carbon Monoxide-Sensing Heme Protein, Cooa, From Carboxydothermus Hydrogenoformans, Laura Wagoner, Josh Wagoner, Thomas Goyne, Robert Clark

Robert Clark

The work reported here is part of a larger effort to determine how amino acid residues that compose the heme pockets of gas-sensing heme proteins impact the proteins’ regulation mechanisms and gas specificity. In the present study, we have employed site-directed mutagenesis to prepare protein variants of the carbon monoxide (CO)-sensing heme protein, CooA, from Carboxydothermus hydrogenoformans. These mutants have been designed in an attempt to rationally alter CooA’s effector specificity. We have prepared, isolated, and purified several protein variants to date, including C80T CooA. The C80T substitution is expected to increase the steric bulk on the proximal face of …

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Coastal Training Market Analysis: Final Report, Kevin O'Brien, Claudette Robey, Daniel Barasckay, Wendy Kellogg, Michael Tevesz Dec 2015

Coastal Training Market Analysis: Final Report, Kevin O'Brien, Claudette Robey, Daniel Barasckay, Wendy Kellogg, Michael Tevesz

Michael J. Tevesz

A market is emerging for policy makers in the area of coastal resources management. Individuals, as professionals or private citizens, are frequently called upon to make decisions regarding coastal environmental issues. The context in which they do so varies considerably; thus education and training in this topic area serves to heighten and expand the knowledge base of the coastal decision-maker.

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Mapping Nominal Values To Numbers For Effective Visualization, Geraldine Rosario, Elke Rundensteiner, David Brown, Matthew Ward Dec 2015

Mapping Nominal Values To Numbers For Effective Visualization, Geraldine Rosario, Elke Rundensteiner, David Brown, Matthew Ward

David C. Brown

Data sets with a large number of nominal variables, some with high cardinality, are becoming increasingly common and need to be explored. Unfortunately, most existing visual exploration displays are designed to handle numeric variables only. When importing data sets with nominal values into such visualization tools, most solutions to date are rather simplistic. Often, techniques that map nominal values to numbers do not assign order or spacing among the values in a manner that conveys semantic relationships. Moreover, displays designed for nominal variables usually cannot handle high cardinality variables well. This paper addresses the problem of how to display nominal …

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Gravitational Slingshot , John Dykla, Robert Cacioppo, Asim Gangopadhyaya Dec 2015

Gravitational Slingshot , John Dykla, Robert Cacioppo, Asim Gangopadhyaya

Asim Gangopadhyaya

The slingshot effect is an intriguing phenomenon that has been used effectively by NASA to send spacecraft to outer edges of the solar system. This phenomenon can be satisfactorily explained by Newtonian physics. However, if it is presented as a problem involving four-momentum conservation, the methods of relativistic kinematics easily lead to the conditions necessary for an accelerating as well as a retarding scenario. This problem provides an example that showcases the frequent utility of relativistic methods to analyze problems of Newtonian mechanics.

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Magnetic Transitions In Disordered Gdal2, D. Williams, Paul Shand, Thomas Pekarek, Ralph Skomski, Valeri Petkov, Diandra Leslie-Pelecky Dec 2015

Magnetic Transitions In Disordered Gdal2, D. Williams, Paul Shand, Thomas Pekarek, Ralph Skomski, Valeri Petkov, Diandra Leslie-Pelecky

Thomas M. Pekarek

The role of disorder in magnetic ordering transitions is investigated using mechanically milled GdAl2. Crystalline GdAl2 is a ferromagnet while amorphous GdAl2 is a spin glass. Nanostructured GdAl2 shows a paramagnetic-to-ferromagnetic transition and glassy behavior, with the temperature and magnitude of each transition dependent on the degree and type of disorder. Disorder is parametrized by a Gaussian distribution of Curie temperatures TC with mean TC and breadth Δ TC. A nonzero coercivity is observed at temperatures more than 20 K above the highest TC of any known Gd-Al phase; however, the coercivity decreases with decreasing temperature over the same temperature …

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New Solvable Singular Potentials , R. Dutt, Asim Gangopadhyaya, C. Rasinariu, Uday Sukhatne Dec 2015

New Solvable Singular Potentials , R. Dutt, Asim Gangopadhyaya, C. Rasinariu, Uday Sukhatne

Asim Gangopadhyaya

We obtain three new solvable, real, shape invariant potentials starting from the harmonic oscillator, Pöschl-Teller I and Pöschl-Teller II potentials on the half-axis and extending their domain to the full line, while taking special care to regularize the inverse square singularity at the origin. The regularization procedure gives rise to a delta-function behavior at the origin. Our new systems possess underlying non-linear potential algebras, which can also be used to determine their spectra analytically.

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Inter-Relations Of Solvable Potentials, Asim Gangopadhyaya, Prasanta Panigrahi, Uday Sukhatne Dec 2015

Inter-Relations Of Solvable Potentials, Asim Gangopadhyaya, Prasanta Panigrahi, Uday Sukhatne

Asim Gangopadhyaya

Solvable Natanzon potentials in nonrelativistic quantum mechanics are known to group into two disjoint classes depending on whether the Schrödinger equation can be reduced to a hypergeometric or a confluent hypergeometric equation. All the potentials within each class are connected via point canonical transformations. We establish a connection between the two classes with appropriate limiting procedures and redefinition of parameters, thereby inter-relating all known solvable potentials.

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Alcohol Reduction Of Enamines, A. Cook Dec 2015

Alcohol Reduction Of Enamines, A. Cook

A. Gilbert Cook

Primary or secondary alcohols will reduce enamines to their corresponding saturated amines when heated in a microwave apparatus at a temperature of 160 degrees C for a period of one hour.

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Impact Of Nitric Oxide (No) Treatment On The Spectroscopic Properties And Dna Binding Activity Of The Carbon Monoxide-Sensing Heme Transcription Factor, Cooa, Edra Jani, Robert Clark Dec 2015

Impact Of Nitric Oxide (No) Treatment On The Spectroscopic Properties And Dna Binding Activity Of The Carbon Monoxide-Sensing Heme Transcription Factor, Cooa, Edra Jani, Robert Clark

Robert Clark

CooA is a carbon monoxide (CO)-sensing heme transcription factor that regulates CO metabolism in several bacteria including Carboxydothermus hydrogenoformans (Ch). The goal of this research was to investigate the spectroscopic properties and DNA binding activity of Fe(III) Ch CooA that was reacted with NO. Based on electronic absorbance spectra, addition of NO to Fe(III) CooA resulted in the formation of a 6-coordinate (6-C) Fe(III)-NO intermediate species, which slowly converted to a 5-coordinate (5-C) Fe(II)-NO complex. A fluorescence anisotropy assay revealed appreciable DNA binding activity by the 6-C Fe(III)-NO form and lesser activity by the 5-C adduct. DNA binding by 5-C …

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Implicit Interest Indicators, Mark Claypool, Phong Le, Makoto Waseda, David Brown Dec 2015

Implicit Interest Indicators, Mark Claypool, Phong Le, Makoto Waseda, David Brown

David C. Brown

Recommender systems provide personalized suggestions about items that users will find interesting. Typically, recommender systems require a user interface that can "intelligently" determine the interest of a user and use this information to make suggestions. The common solution, "explicit ratings", where users tell the system what they think about a piece of information, is well-understood and fairly precise. However, having to stop to enter explicit ratings can alter normal patterns of browsing and reading. A more "intelligent" method is to use implicit ratings, where a rating is obtained by a method other than obtaining it directly from the users. These …

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Trends Analysis Of Coastal Training Programs In The National Estuarine Research Reserve System, Claudette Robey, Kevin O'Brien, Kirstin Toth, Daniel Baracksay, Michael Mcgoun, Wendy Kellogg, Michael Tevesz Dec 2015

Trends Analysis Of Coastal Training Programs In The National Estuarine Research Reserve System, Claudette Robey, Kevin O'Brien, Kirstin Toth, Daniel Baracksay, Michael Mcgoun, Wendy Kellogg, Michael Tevesz

Michael J. Tevesz

The National Estuarine Research Reserves (NERRS) Coastal Training Program (CTP) is a system-wide training program that aims to increase informed decision-making related to coastal resource management at local and regional levels. The CTP serves as the NERRS flagship program for knowledge and information transfer, and provides an effective vehicle to ensure that science-based knowledge and skills get into the hands and minds of those individuals making decisions about the coast on a regular basis in a professional or volunteer capacity. At the local level, Reserve staff conducts intensive planning to develop targeted training programs that complement other training efforts within …

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A New Approach To Harmonic Allocation For Mv Installations, Victor Gosbell, Robert Barr Dec 2015

A New Approach To Harmonic Allocation For Mv Installations, Victor Gosbell, Robert Barr

Robert Barr

Distributors need to allocate a maximum allowed level of harmonic current to MV customers to keep voltage distortion acceptable. The paper describes a new approach, based on the concept of voltage droop, requiring much less calculation and data than required by the present approach based on an IEC technical report. The discrepancy between the new method and the present is studied by comparing some carefully selected scenarios. It is shown that the proposed method gives results within 20% of the standards-based approach which makes it a very attractive alternative for harmonic allocation.

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