1,851 research outputs found
How to report light exposure in human chronobiology and sleep research experiments (Spitschan, Stefani, Blattner, Gronfier, Lockley & Lucas)
No full textSupplementary information for the article "How to report light exposure in human chronobiology and sleep research experiments" by Spitschan, Stefani, Blattner, Gronfier, Lockley & Lucas
Unen kansanterveydellinen ja yhteiskunnallinen merkitys
No full textFrancesco P. Cappuccio, Michelle A. Miller ja Steven W. Lockley (toim.).
Sleep, Health and Society. From Aetiology to Public Health.
Oxford University Press, Oxford 2010, 488 s
Book Review: Eavesdropping: A Memoir of Blindness and Listening
No full textAuthor: Stephen Kuusisto
Reviewer: Steven E. Brown
Publisher: W. W. Norton, 2006
Cloth, ISBN: 0-393-05892-1, 244 pages
Cost: $23.95 US
Light-driven model for identifying indicators of non-visual health potential in the built environment
No full textThis thesis introduces a new approach to characterize and evaluate ocular light exposure based on the discovery of novel blue light-sensitive photoreceptors in the human eye. These photoreceptors are the primary mediators of 'non-visual' responses impacting human health, from resetting the circadian clock to directly alerting the brain. In recent years, studies have found that light at short-wavelengths is more effective than light at longer wavelengths at inducing and suppressing a range of 'non-visual' responses. Although it has been recommended that we approximate the spectral sensitivity of these novel photoreceptors with an action spectra peaking near 490 nm, the optimal approach for quantifying non-visual spectral effectiveness is yet unknown. These novel photoreceptors, in addition being photoreceptors themselves, receive inputs from the classical photoreceptors (rods and cones) that in return affect the overall spectral sensitivity of the non-visual system as it changes with lighting conditions. Due to this time-varying spectral sensitivity and the relatively slow temporal processing, the relation between dynamic external light stimuli and the magnitude of non-visual responses cannot be explained with a single function or a simple threshold value. To better understand these non-linear and unknown relations, this thesis aims to develop a novel computational method, based on recent findings about the 'non-visual' - also called non-image-forming - effects of light on human health. A dynamic wavelength-dependent model framework is proposed to evaluate the non-visual health potential of light. This novel approach integrates the spectral effectiveness of irradiation and accommodates time-varying spectral sensitivity functions. These time series of light quantities serve as inputs for the light-driven model, which accounts for light intensity, duration, history, and timing of light exposure. By quantifying light in terms of spectral effectiveness and temporal dynamics, different light exposure patterns can be ranked in terms of its potential to have an impact on human health. The final objective of this thesis is to support the design of healthier buildings by applying evidence-based lighting criteria, which can then inform architectural design through a simulation-based approach. Incorporating non-visual effects into a building simulation workflow requires a good approximation of daylight spectra as it varies with sun position and sky type. Performance predictions must also account for occupant behavior and scheduling, which brings us to the question: How can we apply such a method to make informed decisions about our built environment? The integration of the proposed model into a functional simulation workflow is demonstrated using an architectural case study but first the non-visual spectral effectiveness of light will be evaluated under varying sky conditions to analyze the model output sensitivity to input accuracy. The model and its application to the built environment will then be investigated using multiple view directions and by considering occupant behavior and scheduling to make an immersive prediction within a space. This novel computational approach can be seen as a first step towards human-centric lighting application, simulating an occupant's light consumption to evaluate non-visual health potential that can support decision-making in the built environment.LIPI
Faces and Places in Fashion: Steven Stipelman
No full textPart presentation, part Q&A, FIT's "Faces & Places in Fashion" lecture series is an opportunity to connect students and the public alike to the pulse of the fashion industry in an open and conversational setting.Our first remote class featured Steven Stipelman, professor of Fashion design/art at FIT since 1993. Professionally, his career goes back more than 40 years. His first job was staff illustrator at Henri Bendel, one of the most fashion forward stores of the period. He drew all the newspaper and promotional ads. His next job, and perhaps the one he is most associated with was an illustrator for Women's wear Daily and "W" for more than 25 years. He illustrated major American and European collections - designer to couture. He worked with these designers often sketching the garments before they were ever made. He learned a great deal of how the collections were created as well as construction and fabrication.Steven's work has been printed internationally and some of his clients included Lord & Taylor, Marshall Field, Estee Lauder, Orlane, Yves St Laurent cosmetics, Bill Blass, Pierre Cardin, Christian Dior, Valentino, Tuleh, Blassport, Basile and Ralph Rucci. His work has appeared in many shows and exhibitions throughout the country. In 2007, he had a one-person exhibition, "Ethereal Elegance," at the Museum at FIT. He is the author of a textbook, "Illustrating Fashion - Concept to Creation." He would describe his work as giving an impression of movement through a spontaneity of brush strokes and washes of acrylic or watercolor. He wants his figures to always have an ethereal or swan-like look, as if they were floating across the page. The drawing should project an emotion that would make you want to feel that way rather than look that way
Ocular measures of sleepiness are increased in night shift workers undergoing a simulated night shift near the peak time of the 6-sulfatoxymelatonin rhythm
No full textStudy Objectives: The study examined the relationship between the circadian rhythm of 6-sulphatoxymelatonin (aMT6s) and ocular measures of sleepiness and neurobehavioral performance in shift workers undergoing a simulated night shift. Methods: Twenty-two shift workers (mean age 33.4, SD 11.8 years) were tested at approximately the beginning (20:00) and the end (05:55) of a simulated night shift in the laboratory. At the time point corresponding to the end of the simulated shift, 14 participants were classified as being within range of 6-sulphatoxymelatonin (aMT6s) acrophase— defined as 3 hours before or after aMT6s peak—and 8 were classified as outside aMT6s acrophase range. Participants completed the Karolinska Sleepiness Scale (KSS) and the auditory psychomotor vigilance task (aPVT). Waking electroencephalography (EEG) was recorded and infrared reflectance oculography was used to collect ocular measures of sleepiness: positive and negative amplitude/velocity ratio (PosAVR, NegAVR), mean blink total duration (BTD), the percentage of eye closure (%TEC), and a composite score of sleepiness levels (Johns Drowsiness Scale; JDS). Results: Participants who were tested within aMT6s acrophase range displayed higher levels of sleepiness on ocular measures (%TEC, BTD, PosAVR, JDS), objective sleepiness (EEG delta power frequency band), subjective ratings of sleepiness, and neurobehavioral performance, compared to those who were outside aMT6s acrophase range. Conclusions: The study demonstrated that objective ocular measures of sleepiness are sensitive to circadian rhythm misalignment in shift workers. Citation: Ftouni S, Sletten TL, Nicholas CL, Kennaway DJ, Lockley SW, Rajaratnam SM. Ocular measures of sleepiness are increased in night shift workers undergoing a simulated night shift near the peak time of the 6-sulfatoxymelatonin rhythm. J Clin Sleep Med 2015;11(10):1131–1141.Suzanne Ftouni, Tracey L. Sletten, Christian L. Nicholas, David J. Kennaway, Steven W. Lockley, Shantha M.W. Rajaratna
Unified mathematical treatment of complex cascaded bipartite networks: The case of collections of journal papers
No full textIn this study, a mathematical treatment is proposed for analysis of entities and relations among entities in
complex networks consisting of cascaded bipartite networks. This treatment is applied to the case of
collections of journal papers. In this case, entities are distinguishable objects and concepts, such as papers,
references, paper authors, reference authors, paper journals, reference journals, institutions, terms, and term
definitions. Relations are associations between entity-types such as papers and the references they cite, or
paper authors and the papers they write. An entity-relationship model is introduced that explicitly shows
direct links between entity-types and possible useful indirect relations. From this a matrix formulation and
generalized matrix arithmetic are introduced that allow easy expression of relations between entities and
calculation of weights of indirect links and co-occurrence links. Occurrence matrices, equivalence
matrices, membership matrices and co-occurrence matrices are described. A dynamic model of growth
describes recursive relations in occurrence and co-occurrence matrices as papers are added to the paper
collection. Graph theoretic matrices are introduced to allow information flow studies of networks of papers
linked by their citations. Similarity calculations and similarity fusion are explained. Derivation of feature
vectors for pattern recognition techniques is presented. The relation of the proposed mathematical
treatment to seriation, clustering, multidimensional scaling, and visualization techniques is discussed. It is
shown that most existing bibliometric analysis techniques for dealing with collections of journal papers are
easily expressed in terms of the proposed mathematical treatment: co-citation analysis, bibliographic
coupling analysis, author co-citation analysis, journal co-citation analysis, Braam-Moed-vanRaan (BMV)
co-citation/co-word analysis, latent semantic analysis, hubs and authorities, and multidimensional scaling.
This report discusses an extensive software toolkit that was developed for this research for analyzing and
visualizing entities and links in a collection of journal papers. Additionally, an extensive case study is
presented, analyzing and visualizing 60 years of anthrax research through a collection of journal papers.
When dealing with complex networks that consist of cascaded bipartite networks, the treatment presented
here provides a general mathematical framework for all aspects of analysis of static network structure and
network dynamic growth. As such, it provides a basic paradigm for thinking about and modeling such
networks: computing direct and indirect links, expressing and analyzing statistical distributions of network
characteristics, describing network growth, deriving feature vectors, clustering, and visualizing network
structure and growth
Mit Rewolucji Amerykańskiej a heroiczny wizerunek Tadeusza Kościuszki w amerykańskiej prasie w okresie Wczesnej Republiki
No full textThe article offers an analysis of the representations of Tadeusz Kościuszko in early American newspapers (1776-1820). The study shows that the American press presented Kościuszko as a heroic figure, significant in the making of America as a nation through his participation in the War of Independence. Kościuszko was not initially recognized as an important military leader of the Revolution, but he was re-discovered as an American hero after he had distinguished himself as the leader of the 1794 uprising in Poland. The mythologization of Kościuszko consisted in interpreting his life as a struggle for liberty, equality, and republicanism, the values which laid at the foundation of America as a nation.Artykuł stanowi analizę wizerunku Tadeusza Kościuszki we wczesnej prasie amerykańskiej (1776-1820). Wyniki badań wskazują, że prasa amerykańska przedstawiała Kościuszkę jako bohatera, postać ważną dla procesu tworzenia się (powstawania) Ameryki poprzez jego udział w Rewolucji Amerykańskiej. Początkowo Kościuszko nie był uznawany za wojskowego przywódcę Rewolucji, ale został okrzyknięty bohaterem amerykańskim po tym jak wsławił się jako przywódca powstania z 1794 roku w Polsce. Mitologizacja Kościuszki polegała na przedstawianiu jego życia jako walki o wolność, równość i republikanizm, wartości które leżały u podwalin amerykańskiego narodu.Work on this article was supported by the grant from the National Science Centre Poland (NCN) no. 2015/19/B/HS/01941. The author wishes to express gratitude to Prof. Tim Lockley and the Department of History, University of Warwick, UK for assistance in carrying out this research.Uniwersytet Marii Curie-Skłodowskiej w LublinieEarly American Newspapers, Series 1, 1690-1876, Readex America’s Historical Newspapers [Online]. Available at:http://0-infoweb.newsbank.com.pugwash.lib.warwick.ac.uk//Blakemore, Steven, Literature, Intertextuality, and the American Revolution: from Common Sense to “Rip Van Winkle”, Lanham 2014.Campbell, Joseph, The Hero with a Thousand Faces, Princeton 1949.Cavender, Gray, and Sarah Prior, Constructing the Military Hero, “International Journal of Criminology and Sociology”, vol. 2 (2013).Clark, Charles E., The Public Prints: The Newspaper in Anglo-American Culture, 1665-1740, New York 1994.Copeland, David A., Colonial American Newspapers: Character and Content, Newark 1997.Dierks, Konstantin, In My Power : Letter Writing and Communications in Early America, Philadelphia 2011.Habermas Jürgen, The Structural Transformation of the Public Sphere: An Inquiry into a Category of Bourgeois Society, Cambridge 1989.Haiman, Miecislaus, Kosciuszko in the American Revolution, New York 1975.Humphrey, Carol Sue, The Press of the Young Republic, 1783-1833, Westport 1996.Kajencki, Francis C., Thaddeus Kosciuszko: Military Engineer of the American Revolution, El Paso 1998.Klapp, Orrin, Heroes, Villains and Fools as Agents of Social Control, “American Sociological Review” 19(1954), http://dx.doi.org/10.2307/2088173.Kozłowski, W.M., Kościuszko w West-Point, „Przegląd Historyczny”, vol. 10 (1910).Leder, Lawrence H., The Role of Newspapers in Early America: “In Defense of Their Own Liberty, “Huntington Library Quarterly”, vol. 30 (1966).Linenthal, Edward Tabor, Changing Images of the Warrior Hero in America: A History of Popular Symbolism, New York 1982.Mugridge, Ian, Myth-Making and History, “The International History Review”, vol. 5 (1983).Micińska Magdalena, The Myth of Tadeusz Kościuszko in the Polish Mind (1794-1997), “European Review of History - Revue européenne d’Histoire”, vol. 5 (1998), 191-196.Nash, Gary and Graham Russell Hodges, Friends of Liberty: A Tale of Three Patriots, Two Revolutions, and the Betrayal that Divided a Nation: Thomas Jefferson, Thaddeus Kosciuszko, and Agrippa Hull, New York 2008.Newman, Simon, Parades and the Politics of the Street: Festive Culture in the Early American Republic, Philadelphia 1997.Pula, James S., Thaddeus Kościuszko: The Purest Son of Liberty, New York 1999.Ramsey, David, History of the American Revolution, 2 vols, Philadelphia 1789.Shields David S., Civil Tongues and Polite Letters in British America, Williamsburg 1997.Schlesinger Arthur M., Prelude to Independence: The Newspaper War on Britain, 1764-1776, New York 1958.Slotkin, Richard, Regeneration Through Violence: The Mythology of the American Frontier, 1600-1860, Middletown 1973.Storozynski Alex, The Peasant Prince: Thaddeus Kosciuszko and the Age of Revolution, New York 2010.Torsella, Joseph M., American National Identity, 1750-1790: Samples from the Popular Press, “The Pennsylvania Magazine of History and Biography”, vol. 112 (1988).Thompson Peter, Rum Punch and Revolution: Taverngoing and Public Life in Eighteenth-Century Philadelphia, Philadelphia 1998.Tyler, Moses C., The Literary History of the American Revolution: 1763–1863, New York 1957.Zapatka, Francis E. “Kościuszko in Early American Literature”, Polish American Studies, vol. 47 (1990).15536
Electromagnetics, Volume 2
No full textElectromagnetics, volume 2 by Steven W. Ellingson is a 216-page peer-reviewed open textbook designed especially for electrical engineering students in the third year of a bachelor of science degree program. It is intended as the primary textbook for the second semester of a two-semester undergraduate engineering electromagnetics sequence. The book addresses magnetic force and the Biot-Savart law; general and lossy media; parallel plate and rectangular waveguides; parallel wire, microstrip, and coaxial transmission lines; AC current flow and skin depth; reflection and transmission at planar boundaries; fields in parallel plate, parallel wire, and microstrip transmission lines; optical fiber; and radiation and antennas.
Review or adopt this book
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Three formats of this book are available
- Print (ISBN 9781949373912) Available from Amazon.com
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Table of contents
Chapter 1: Preliminary Concepts
Chapter 2: Magnetostatics Redux
Chapter 3: Wave Propagation in General Media
Chapter 4: Current Flow in Imperfect Conductors
Chapter 5: Wave Reflection and Transmission
Chapter 6: Waveguides
Chapter 7: Transmission Lines Redux
Chapter 8: Optical Fiber
Chapter 9: Radiation
Chapter 10: Antennas
Appendix A: Constitutive Parameters of Some Common Materials
Appendix B: Mathematical Formulas
Appendix C: Physical Constants
The Open Electromagnetics Project
Led by Steven W. Ellingson at Virginia Tech, the goal of the Open Electromagnetics Project is to create no-cost openly-licensed content for courses in engineering electromagnetics. The project is motivated by two things: lowering learning material costs for students and giving faculty the freedom to adopt, modify, and improve their educational resources.
Books in this series
Electromagnetics, Volume 1 https://doi.org/10.21061/electromagnetics-vol-1
Electromagnetics, Volume 2 https://doi.org/10.21061/electromagnetics-vol-2
To express your interest in a book or this series, please visit http://bit.ly/vtpublishing-updates
Suggested citation
Ellingson, Steven W. (2020) Electromagnetics, Vol. 2. Blacksburg, VA: Virginia Tech Publishing. https://doi.org/10.21061/electromagnetics-vol-2 CC BY-SA 4.0
About the author
Steven W. Ellingson ([email protected]) is an Associate Professor at Virginia Tech in Blacksburg, Virginia in the United States. He received PhD and MS degrees in Electrical Engineering from the Ohio State University and a BS in Electrical & Computer Engineering from Clarkson University. He was employed by the US Army, Booz-Allen & Hamilton, Raytheon, and the Ohio State University ElectroScience Laboratory before joining the faculty of Virginia Tech, where he teaches courses in electromagnetics, radio frequency systems, wireless communications, and signal processing. His research includes topics in wireless communications, radio science, and radio frequency instrumentation. Professor Ellingson serves as a consultant to industry and government and is the author of Radio Systems Engineering (Cambridge University Press, 2016).
Publication of this book was made possible in part by the Open Education Faculty Initiative Grant program at the University Libraries at Virginia Tech.
http://guides.lib.vt.edu/oer/grants
Cover design: Robert Browder
Cover image: (c) Michelle Yost. Total Internal Reflection (modified by Robert Browder) is licensed with a Creative Commons Attribution-ShareAlike 2.0 license</a
Electromagnetics, Volume 1
No full textElectromagnetics, volume 1 by Steven W. Ellingson is a 225-page, peer-reviewed open educational resource intended for electrical engineering students in the third year of a bachelor of science degree program. It is intended as a primary textbook for a one-semester first course in undergraduate engineering electromagnetics. The book employs the “transmission lines first” approach in which transmission lines are introduced using a lumped-element equivalent circuit model for a differential length of transmission line, leading to one-dimensional wave equations for voltage and current.
Note: Electromagnetics, volume 2 (2020) is now available at https://doi.org/10.21061/electromagnetics-vol-2.
Suggested citation
Ellingson, Steven W. (2018) Electromagnetics, Vol. 1. Blacksburg, VA: VT Publishing. https://doi.org/10.21061/electromagnetics-vol-1 CC BY-SA 4.0
Three formats of this book are available:
- Print (ISBN 9780997920185) Available from Amazon.com
- PDF (ISBN 9780997920192)
- LaTeX source files
Report adoption of this book here. If you are a professor reviewing, adopting, or adapting this textbook please help us understand your use by completing this form.
Additional resources
- Problem sets and the corresponding solution manual.
- Slides of figures used in and created for the book.
- Errata for Volume 1
- Community portal for the Electromagnetics series
- Faculty listserv for the Electromagnetics series
- Submit feedback and suggestions
- Independent Reviews
Table of contents
Chapter 1: Preliminary Concepts
Chapter 2: Electric and Magnetic Fields
Chapter 3: Transmission Lines
Chapter 4: Vector Analysis
Chapter 5: Electrostatics
Chapter 6: Steady Current and Conductivity
Chapter 7: Magnetostatics
Chapter 8: Time-Varying Fields
Chapter 9: Plane Waves in Lossless Media
Appendixes
A. Constitutive Parameters of Some Common Materials
B. Mathematical Formulas
C. Physical Constants
The Open Electromagnetics Project
Led by Steven W. Ellingson at Virginia Tech, the goal of the Open Electromagnetics Project is to create no-cost openly-licensed content for courses in engineering electromagnetics. The project is motivated by two things: lowering learning material costs for students and giving faculty the freedom to adopt, modify, and improve their educational resources.
Books in this series
Electromagnetics, Volume 1 https://doi.org/10.21061/electromagnetics-vol-1
Electromagnetics, Volume 2 https://doi.org/10.21061/electromagnetics-vol-2
To express your interest in a book or this series, please visit http://bit.ly/vtpublishing-updates
This book improves on Electromagnetics Volume 1 (beta) with the investment of field testing, copyediting, and technical review. Changes include correction of errors identified in the beta version errata and many minor improvements, addition of an index, addition of a separate manual of examples and solutions, and LaTeX source files for the book.
About the author
Steven W. Ellingson ([email protected]) is an Associate Professor at Virginia Tech in Blacksburg, Virginia in the United States. He received PhD and MS degrees in Electrical Engineering from the Ohio State University and a BS in Electrical & Computer Engineering from Clarkson University. He was employed by the US Army, Booz-Allen & Hamilton, Raytheon, and the Ohio State University ElectroScience Laboratory before joining the faculty of Virginia Tech, where he teaches courses in electromagnetics, radio frequency systems, wireless communications, and signal processing. His research includes topics in wireless communications, radio science, and radio frequency instrumentation. Professor Ellingson serves as a consultant to industry and government and is the author of Radio Systems Engineering (Cambridge University Press, 2016).
Publication of this book was made possible in part by the Open Education Faculty Initiative Grant program at the University Libraries at Virginia Tech.
http://guides.lib.vt.edu/oer/grants
Cover design: Robert Browder
Cover image: (c) Michelle Yost. Total Internal Reflection (modified by Robert Browder) is licensed with a Creative Commons Attribution-ShareAlike 2.0 license</a
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