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Is the Universe Expanding?: an Historical and Philosophical Perspective for Cosmologists Starting Anew
Western Michigan University ScholarWorks at WMU Master's Theses Graduate College 6-1996 Is the Universe Expanding?: An Historical and Philosophical Perspective for Cosmologists Starting Anew David A. Vlosak Follow this and additional works at: https://scholarworks.wmich.edu/masters_theses Part of the Cosmology, Relativity, and Gravity Commons Recommended Citation Vlosak, David A., "Is the Universe Expanding?: An Historical and Philosophical Perspective for Cosmologists Starting Anew" (1996). Master's Theses. 3474. https://scholarworks.wmich.edu/masters_theses/3474 This Masters Thesis-Open Access is brought to you for free and open access by the Graduate College at ScholarWorks at WMU. It has been accepted for inclusion in Master's Theses by an authorized administrator of ScholarWorks at WMU. For more information, please contact [email protected]. IS THEUN IVERSE EXPANDING?: AN HISTORICAL AND PHILOSOPHICAL PERSPECTIVE FOR COSMOLOGISTS STAR TING ANEW by David A Vlasak A Thesis Submitted to the Faculty of The Graduate College in partial fulfillment of the requirements forthe Degree of Master of Arts Department of Philosophy Western Michigan University Kalamazoo, Michigan June 1996 IS THE UNIVERSE EXPANDING?: AN HISTORICAL AND PHILOSOPHICAL PERSPECTIVE FOR COSMOLOGISTS STARTING ANEW David A Vlasak, M.A. Western Michigan University, 1996 This study addresses the problem of how scientists ought to go about resolving the current crisis in big bang cosmology. Although this problem can be addressed by scientists themselves at the level of their own practice, this study addresses it at the meta level by using the resources offered by philosophy of science. There are two ways to resolve the current crisis. -
Revisions to Microwave Spectrum Utilization Policies in the Range of 1-20 Ghz
SP 1-20 GHz January 1995 Spectrum Management Spectrum Utilization Policy Revisions to Microwave Spectrum Utilization Policies in the Range of 1-20 GHz Notice No. DGTP-002-95 Amended by: DGTP-006-99 Amendments to the Microwave Spectrum Utilization Policies in the 1-3 GHz Frequency Range (October 1999) DGTP-006-97 Proposals to Provide New Opportunities for the Use of the Radio Spectrum in the 1-20 GHz Frequency Range (August 1997) DGTP-007-97 Spectrum Policy Provisions to Permit the Use of Digital Radio Broadcasting Installations to Provide to Non-Broadcasting Services (September 1997) DGTP-004-97 Licence Exempt Personal Communications Services in the Frequency Band 1910-1930 MHz (April 1997) DGTP-005-95 / Policy and Call for Applications: Wireless Personal Communications Services in the 2 GHz Range, Implementing PCS DGRB-002-95 in Canada (June 1995) DGTP-007-00 / Policy and Licensing Procedures for the Auction of the Additional PCS Spectrum in the 2 GHz Frequency Range DGRB-005-00 (June 2000) DGTP-003-01 Revisions to the Spectrum Utilization Policy for Services in the Frequency Range 2285-2483.5 MHz (June 2001) DGRB-003-03 Policy and Licensing Procedures for the Auction of Spectrum Licences in the 2300 MHz and 3500 MHz Bands (September 2003) DGRB-006-99 Policy and Licensing Procedures - Multipoint Communications Systems in the 2500 MHz Range (June 1999) DGTP-004-04 Revisions to Allocations in the Band 2500-2690 MHz and Consultation on Spectrum Utilization (April 2004) DGTP-008-04 Revisions to Spectrum Utilization Policies in the 3-30 GHz -
Radio Spectrum a Key Resource for the Digital Single Market
Briefing March 2015 Radio spectrum A key resource for the Digital Single Market SUMMARY Radio spectrum refers to a specific range of frequencies of electromagnetic energy that is used to communicate information. Applications important for society such as radio and television broadcasting, civil aviation, satellites, defence and emergency services depend on specific allocations of radio frequency. Recently the demand for spectrum has increased dramatically, driven by growing quantities of data transmitted over the internet and rapidly increasing numbers of wireless devices, including smartphones and tablets, Wi-Fi networks and everyday objects connected to the internet. Radio spectrum is a finite natural resource that needs to be managed to realise the maximum economic and social benefits. Countries have traditionally regulated radio spectrum within their territories. However despite the increasing involvement of the European Union (EU) in radio spectrum policy over the past 10 to 15 years, many observers feel that the management of radio spectrum in the EU is fragmented in ways which makes the internal market inefficient, restrains economic development, and hinders the achievement of certain goals of the Digital Agenda for Europe. In 2013, the European Commission proposed legislation on electronic communications that among other measures, provided for greater coordination in spectrum management in the EU, but this has stalled in the face of opposition within the Council. In setting out his political priorities, Commission President Jean-Claude Juncker has indicated that ambitious telecommunication reforms, to break down national silos in the management of radio spectrum, are an important step in the creation of a Digital Single Market. The Commission plans to propose a Digital Single Market package in May 2015, which may again address this issue. -
RTT TECHNOLOGY TOPIC January 2015 Defence Spectrum – the New Battleground?
RTT TECHNOLOGY TOPIC January 2015 Defence Spectrum – the new battleground? In this month’s technology topic we look at contemporary military radio developments, the integration of LTE user devices into defence communication systems, the relevance of military research to 5 G deployment efficiency and related spectral utilisation and regulatory issues. Defence communication systems are deployed across the whole radio spectrum from long wave to light. This includes mobile communication systems at VHF and UHF and L Band and S band, LEO, MEO and GSO satellite systems (VHF to E band) and mobile and fixed radar (VHF to E band). Legacy defence systems are being upgraded to provide additional functionality. This requires more rather than less spectrum. Increased radar resolution requires wider channel bandwidths; longer range requires more power and improved sensitivity. Improved sensitivity increases the risk of inter system interference. Emerging application requirements including unmanned aerial vehicles require a mix of additional terrestrial, satellite and radar bandwidth. These requirements are geographically and spectrally diverse rather than battlefield and spectrally specific. The assumption in many markets is that the defence industry will be willing and able to surrender spectrum for mobile broadband consumer and civilian use. The AWS 3 auction in the US is a contemporary example with a $5 billion transition budget to cover legacy military system decommissioning in the DOD coordination zone between 1755 and 1780 MHz This transition strategy assumes an increased use of LTE network hardware and user hardware in battlefield systems. While this might imply an opportunity for closer coordination and cooperation between the mobile broadband and defence community it seems likely that an increase in the amount of defence bandwidth needed to support a broadening range of RF dependent systems could be a problematic component in the global spectral allocation and auction process. -
Ncar S-Pol Second Frequency (K -Band) Radar
P12R.6 NCAR S-POL SECOND FREQUENCY (KA-BAND) RADAR Gordon Farquharson,∗ Frank Pratte, Milan Pipersky, Don Ferraro, Alan Phinney, Eric Loew, Robert Rilling, Scott Ellis, and Jothiram Vivekanandan National Center for Atmospheric Research, Boulder, Colorado 1. INTRODUCTION The National Center for Atmospheric Research (NCAR) has recently extended the observational capability of the S-band dual-polarimetric weather radar system (S-Pol, Keeler et al. (2000)) by adding a Ka-band (35 GHz) po- larimetric Doppler radar (Vivekanandan et al., 2004). The Transmitter Ka-band radar employs a dual channel receiver and can be configured for either HH and HV, or HH and VV polari- metric measurements. The Ka-band and S-band antenna beams are matched and aligned, and timing signals for both systems are generated from the Global Position Sys- tem (GPS) ensuring that a common resolution volume is sampled by both systems. This dual-wavelength capabil- ity provides the potential for retrieving water vapor profiles Radar Processor (Ellis et al., 2005) and liquid water content in Rayleigh scattering conditions (Vivekanandan et al., 1999), im- proving remote sensing of various precipitation types, and studies on cloud microphysics. 2. RADAR DESCRIPTION Receiver The K -band radar is housed in three enclosures which a Figure 1: K -band radar attached to the S-band dish. The are mounted to the S-Pol S-band dish and pedestal struc- a transmitter, receiver, and processor enclosures are vis- ture (Figure 1); these include the transmitter enclosure, ible. The K -band antenna is mounted to the receiver the receiver enclosure, and the radar processor enclo- a enclosure and is facing away from the viewer in the pho- sure. -
EHC 238 Front Pages Final.Fm
This report contains the collective views of an international group of experts and does not necessarily represent the decisions or the stated policy of the International Commission of Non- Ionizing Radiation Protection, the International Labour Organization, or the World Health Organization. Environmental Health Criteria 238 EXTREMELY LOW FREQUENCY FIELDS Published under the joint sponsorship of the International Labour Organization, the International Commission on Non-Ionizing Radiation Protection, and the World Health Organization. WHO Library Cataloguing-in-Publication Data Extremely low frequency fields. (Environmental health criteria ; 238) 1.Electromagnetic fields. 2.Radiation effects. 3.Risk assessment. 4.Envi- ronmental exposure. I.World Health Organization. II.Inter-Organization Programme for the Sound Management of Chemicals. III.Series. ISBN 978 92 4 157238 5 (NLM classification: QT 34) ISSN 0250-863X © World Health Organization 2007 All rights reserved. Publications of the World Health Organization can be obtained from WHO Press, World Health Organization, 20 Avenue Appia, 1211 Geneva 27, Switzerland (tel.: +41 22 791 3264; fax: +41 22 791 4857; e- mail: [email protected]). Requests for permission to reproduce or translate WHO publications – whether for sale or for noncommercial distribution – should be addressed to WHO Press, at the above address (fax: +41 22 791 4806; e-mail: [email protected]). The designations employed and the presentation of the material in this publication do not imply the expression of any opinion whatsoever on the part of the World Health Organization concerning the legal status of any country, territory, city or area or of its authorities, or concerning the delimitation of its frontiers or boundaries. -
Cosmic Infrared Background and Early Galaxy Evolution
Cosmic Infrared Background and Early Galaxy Evolution A. Kashlinsky Laboratory for Astronomy and Solar Physics, Goddard Space Flight Center, Greenbelt, MD 20771, and SSAI e-mail address: [email protected] ABSTRACT The Cosmic Infrared Background (CIB) reflects the sum total of galactic luminosi- ties integrated over the entire age of the universe. From its measurement the red-shifted starlight and dust-absorbed and re-radiated starlight of the CIB can be used to deter- mine (or constrain) the rates of star formation and metal production as a function of time and deduce information about objects at epochs currently inaccessible to telescopic studies. This review discusses the state of current CIB measurements and the (mostly space-based) instruments with which these measurements have been made, the obstacles (the various foreground emissions) and the physics behind the CIB and its structure. Theoretical discussion of the CIB levels can now be normalized to the standard cos- mological model narrowing down theoretical uncertainties. We review the information behind and theoretical modeling of both the mean (isotropic) levels of the CIB and their fluctuations. The CIB is divided into three broad bands: near-IR, mid-IR and far-IR. For each of the bands we review the main contributors to the CIB flux and the epochs at which the bulk of the flux originates. We also discuss the data on the various quanti- ties relevant for correct interpretation of the CIB levels: the star-formation history, the present-day luminosity function measurements, resolving the various galaxy contribu- tors to the CIB, etc. The integrated light of all galaxies in the deepest near-IR galaxy counts to date fails to match the observed mean level of the CIB, probably indicating arXiv:astro-ph/0412235v1 9 Dec 2004 a significant high-redshift contribution to the CIB. -
Applied Engineering Using Schumann Resonance for Earthquakes Monitoring
applied sciences Article Applied Engineering Using Schumann Resonance for Earthquakes Monitoring Jose A. Gazquez 1,2, Rosa M. Garcia 1,2, Nuria N. Castellano 1,2 ID , Manuel Fernandez-Ros 1,2 ID , Alberto-Jesus Perea-Moreno 3 ID and Francisco Manzano-Agugliaro 1,* ID 1 Department Engineering, University of Almeria, CEIA3, 04120 Almeria, Spain; [email protected] (J.A.G.); [email protected] (R.M.G.); [email protected] (N.N.C.); [email protected] (M.F.-R.) 2 Research Group of Electronic Communications and Telemedicine TIC-019, 04120 Almeria, Spain 3 Department of Applied Physics, University of Cordoba, CEIA3, Campus de Rabanales, 14071 Córdoba, Spain; [email protected] * Correspondence: [email protected]; Tel.: +34-950-015396; Fax: +34-950-015491 Received: 14 September 2017; Accepted: 25 October 2017; Published: 27 October 2017 Abstract: For populations that may be affected, the risks of earthquakes and tsunamis are a major concern worldwide. Therefore, early detection of an event of this type in good time is of the highest priority. The observatories that are capable of detecting Extremely Low Frequency (ELF) waves (<300 Hz) today represent a breakthrough in the early detection and study of such phenomena. In this work, all earthquakes with tsunami associated in history and all existing ELF wave observatories currently located worldwide are represented. It was also noticed how the southern hemisphere lacks coverage in this matter. In this work, the most suitable locations are proposed to cover these geographical areas. Also, ELF data processed obtained from the observatory of the University of Almeria in Calar Alto, Spain are shown. -
Spectrum and the Technological Transformation of the Satellite Industry Prepared by Strand Consulting on Behalf of the Satellite Industry Association1
Spectrum & the Technological Transformation of the Satellite Industry Spectrum and the Technological Transformation of the Satellite Industry Prepared by Strand Consulting on behalf of the Satellite Industry Association1 1 AT&T, a member of SIA, does not necessarily endorse all conclusions of this study. Page 1 of 75 Spectrum & the Technological Transformation of the Satellite Industry 1. Table of Contents 1. Table of Contents ................................................................................................ 1 2. Executive Summary ............................................................................................. 4 2.1. What the satellite industry does for the U.S. today ............................................... 4 2.2. What the satellite industry offers going forward ................................................... 4 2.3. Innovation in the satellite industry ........................................................................ 5 3. Introduction ......................................................................................................... 7 3.1. Overview .................................................................................................................. 7 3.2. Spectrum Basics ...................................................................................................... 8 3.3. Satellite Industry Segments .................................................................................... 9 3.3.1. Satellite Communications .............................................................................. -
MT. AIRY MIDDLE SCHOOL 410-751-3554 102 Watersville Road • Mt
MT. AIRY MIDDLE SCHOOL 410-751-3554 102 Watersville Road • Mt. Airy, Maryland 21771 301-829-1314 Fax 410-549-6475 Karl T. Streaker, Principal Andrew S. Bowers, Assistant Principal Dear Parents/Guardians, Upcoming Events We’ve enjoyed a wonderful start to the school year. I would like to thank our students, staff, and parents for your contributions to our school November community. The first few months have been very busy and rewarding. We held two school assemblies, an anti-bullying presentation from Camfel 1 Picture Retake Productions and our Vision kick-off assembly, began our school clubs, 1 PTO Meeting; 7:00pm Media Center completed our Vision t-shirt design contest, and our 6th graders attended 4 Early Dismissal (Mt. Airy Middle @ 12:15pm) outdoor school. The upcoming months are sure to be equally as busy with 7 Schools Closed for Students the drama club’s production of “Dorothy in Wonderland”, our winter concerts, and service opportunities for students. 8 Schools/Offices Closed; General Election Day 11 Report Cards Distributed In November, we will be holding our Can & Coat Drive to support local 16 Parent/Teacher Conferences; 3:30pm-7:15pm food pantries and the “Call for Coats” program. Students are encouraged to 16 Volunteer Training; 6:00pm bring in non-perishable food and coats during the drive. All students who 17 8th Grade Field Trip to Career & Technology Center make donations will be entered into a drawing. Students will be selected to 18 Dorothy in Wonderland; 7:00pm choose a staff member to perform for the entire student body during an 23 Early Dismissal (Mt. -
05-Winter-Newsletter.Pdf (1.32
Open House Draws Crowd Prospective students from Hagerstown and the surround- ing areas came out in the first snow squall of the season to NOTES and NEWS learn more about the programs offered at USMH. University System of Maryland at Hagerstown Counselors from the four participating universities were 32 W. Washington Street, Hagerstown, MD 21740 available to provide information and answer questions. O O Current students participated in a poster session, showcas- 240-527-2060 Voice TDD 240-527-2064 www.hagerstown.usmd.edu ing their work for open house attendees . HAGERSTOWN Winter 2005 College Park Brings Engineering Above: Casie Peterson and Jennifer Miller, FSU business students, prepared a poster and game to display during the open house. to USMH Left: Paul Easterling (right), associate director of the Professional Master of Engineering Program at University of Maryland, College Park, and Dr. George Syrmos (second from right), director of the program, chat with The University of Maryland, College Park, launched its first prospective students during the recent open house. program to be offered at the University System of Maryland at Hagerstown during a reception on December 1. Graduate engineering courses will be offered by the System's flagship school beginning in January 2006. "The University of Maryland, College Park is in Washington County as of two o'clock today," said Dr. David Warner, executive director of USMH. "I am thrilled to make that state- ment." A University of Maryland, College Park flag was unveiled, joining the flags of the three other participating schools at USMH. Holiday Hours Weather-Related Closings and Delays Timothy Troxell, executive director of the Hagerstown- Washington County Economic Development Commission, said that having College Park join the Hagerstown campus USMH will be closed from Friday, December 23 through Winter weather is upon us. -
A Layman's Interpretation Guide L-Band and C-Band Synthetic
A Layman’s Interpretation Guide to L-band and C-band Synthetic Aperture Radar data Version 2.0 15 November, 2018 Table of Contents 1 About this guide .................................................................................................................................... 2 2 Briefly about Synthetic Aperture Radar ......................................................................................... 2 2.1 The radar wavelength .................................................................................................................... 2 2.2 Polarisation ....................................................................................................................................... 3 2.3 Radar backscatter ........................................................................................................................... 3 2.3.1 Sigma-nought .................................................................................................................................................. 3 2.3.2 Gamma-nought ............................................................................................................................................... 3 2.4 Backscatter mechanisms .............................................................................................................. 4 2.4.1 Direct backscatter ......................................................................................................................................... 4 2.4.2 Forward scattering ......................................................................................................................................