196,606 research outputs found
Long-term lightcurves from combined unified very high energy g-ray data
No full textContext. Very high-energy (VHE, E > 100 GeV)
γ-ray data are a valuable input for multi-wavelength and
multi-messenger (e.g. combination with neutrino data) studies.
Aims. We aim at the conservation and homogenization of historical,
current, and future VHE γ-ray-data on active galactic nuclei (AGN).
Methods. We have collected lightcurve data taken by major VHE
experiments since 1991 and combined them into long-term lightcurves for several AGN, and
now provide our collected datasets for further use. Due to the lack of common data formats
in VHE γ-ray astronomy, we have defined relevant datafields to be stored
in standard data formats. The time variability of the combined VHE lightcurve data was
investigated, and correlation with archival X-ray data collected by
RXTE/ASM tested.
Results. The combination of data on the prominent blazar Mrk 421 from
different experiments yields a lightcurve spanning more than a decade. From this combined
dataset we derive an integral baseline flux from Mrk 421 that must be lower than 33% of
the Crab Nebula flux above 1 TeV. The analysis of the time variability yields log-normal
flux variations in the VHE-data on Mrk 421.
Conclusions. Existing VHE data contain valuable information concerning
the variability of AGN and can be an important ingredient for multi-wavelength or
multi-messenger studies. In the future, upcoming and planned experiments will provide more
data from many transient objects, and the interaction of VHE astronomy with classical
astronomy will intensify. In this context a unified and exchangeable data format will
become increasingly important
Dr. Duane M. Jackson, Morehouse College, July 2011
No full textThis video is a conversation with Dr. Duane M. Jackson. Dr. Jackson talks about his paper, "Recall and the Serial Position Effect: The Role of Primacy and Recency on Accounting Students' Performance." Jackie Daniel, AUC Woodruff Library, is the interviewer
"Reflections on the subject of Emigration from Europe with a view to Settlement in the United States" By M. Carey.
No full text"Reflections on the subject of Emigration from Europe with a view to Settlement in the United States: containing bried sketches of the moral and political character of those states.
By M. Carey, member of the American philosophical, and of the American Antiquarian Society, and author of The Olive Branch, Cindiciae Hibernicae, essays on banking, on political economy, and on internal improvement.
To which are now added the English editor's comments on the subject; together with Important Advice to Emigrants, and Cautions Against Impositions Practiced in the Outports
Dispelling the Myths Behind First-author Citation Counts
No full textWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Dr. Glendon Swarthout
No full textHosted by Roger M. Busfield, MSU Assistant Professor of Speech and Theater, Meet the Author is designed to introduce a general audience to a contemporary author and their work through in-depth interviews. This episode features a conversation between Dr. Glendon Swarthout, prolific author and English professor at MSU, and assistant professors Sam S. Baskett and Theodore B. Strandness
Simulation of thermal plant optimization and hydraulic aspects of thermal distribution loops for large campuses
No full textFollowing an introduction, the author describes Texas A&M University and its utilities system. After that, the author presents how to construct simulation models for chilled water and heating hot water distribution systems. The simulation model was used in a $2.3 million Ross Street chilled water pipe replacement project at Texas A&M University. A second project conducted at the University of Texas at San Antonio was used as an example to demonstrate how to identify and design an optimal distribution system by using a simulation model. The author found that the minor losses of these closed loop thermal distribution systems are significantly higher than potable water distribution systems. In the second part of the report, the author presents the latest development of software called the Plant Optimization Program, which can simulate cogeneration plant operation, estimate its operation cost and provide optimized operation suggestions. The author also developed detailed simulation models for a gas turbine and heat recovery steam generator and identified significant potential savings. Finally, the author also used a steam turbine as an example to present a multi-regression method on constructing simulation models by using basic statistics and optimization algorithms. This report presents a survey of the author??s working experience at the Energy Systems Laboratory (ESL) at Texas A&M University during the period of January 2002 through March 2004. The purpose of the above work was to allow the author to become familiar with the practice of engineering. The result is that the author knows how to complete a project from start to finish and understands how both technical and nontechnical aspects of a project need to be considered in order to ensure a quality deliverable and bring a project to successful completion. This report concludes that the objectives of the internship were successfully accomplished and that the requirements for the degree of Degree of Engineering have been satisfied
HiSCORE: a new detector for astroparticle and particle physics beyond 10 TeV
No full textProceedings of the Third Roma International Conference on Astroparticle Physics (RICAP'11) held in Roma at “Roma Tre” University from May 24 to May 27, 2011 / Antonio Capone, Giulia De Bonis, Mario De Vincenzi and Aldo Morselli (eds.)The new large-area (100 km2) wide-angle (0.9 sr) air Cherenkov detector HiSCORE (Hundred i Square-km Cosmic ORigin Explorer) aims at the exploration of the cosmic ray and γ-ray sky (accelerator sky) in the so far poorly covered energy range from 10 TeV to 1 EeV. The main motivation for observations in this energy regime is to solve the origin of Galactic cosmic rays. Other questions of astroparticle and particle physics can be addressed in this energy regime. Furthermore, new physics questions might arise by opening the last remaining observation window of γ-ray astronomy (TeV/PeV). HiSCORE is based on non-imaging Cherenkov light-front sampling with sensitive large-area detector modules of the order of 0.5 m2. Sampling the lateral photon density and arrival-time distribution allows the reconstruction of the direction, the energy and the type (mainly via the shower depth) of the primary particle. © 2012 Elsevier B.V.M. Tluczykont, D. Horns, D. Hampf, R. Nachtigall, U. Einhaus, M. Kunnas, T. Kneiske, G. P. Rowel
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