WorldWideScience

Sample records for astronomy receiver systems

  1. 47 CFR 73.6027 - Class A TV notifications concerning interference to radio astronomy, research and receiving...

    Science.gov (United States)

    2010-10-01

    ... interference to radio astronomy, research and receiving installations. 73.6027 Section 73.6027... radio astronomy, research and receiving installations. An applicant for digital operation of an existing... astronomy, research and receiving installations. [69 FR 69331, Nov. 29, 2004] ...

  2. Electronic warfare receivers and receiving systems

    CERN Document Server

    Poisel, Richard A

    2014-01-01

    Receivers systems are considered the core of electronic warfare (EW) intercept systems. Without them, the fundamental purpose of such systems is null and void. This book considers the major elements that make up receiver systems and the receivers that go in them.This resource provides system design engineers with techniques for design and development of EW receivers for modern modulations (spread spectrum) in addition to receivers for older, common modulation formats. Each major module in these receivers is considered in detail. Design information is included as well as performance tradeoffs o

  3. A submillimeter heterodyne receiver and its application in astronomy

    International Nuclear Information System (INIS)

    Vliet, A.H.F. van.

    1981-01-01

    A submm heterodyne receiver for astronomical observations has been developed which operates in the frequency range between 460 and 500 GHz. An InSb hot electron bolometer is used as the mixing element. The local oscillator power is obtained by doubling the frequency of a backward wave oscillator (B.W.O.). The sideband noise of the B.W.O. has appeared to be sufficiently weak to allow its use in combination with an InSb mixer. A method of measuring the matching of the mixer to the waveguide is described and some results of measurements of B.W.O. noise are given. A general description is presented of Gaussian beam theory and this is applied to the design of the receiver optics. Particular attention is given to the coupling between the receiver and the telescope. To prevent the usually troublesome effects of standing waves between the receiver and the telescope a circular polarizer can be applied. A review is given of different types of such polarizers as presently used in the optical and microwave regimes, with a view to their application in the submm range. Two types of circular polarizers were constructed and results of measurements on these are given. The final chapter describes the observation of the rotational CO J = 4→3 transition at 461 GHz in the Kleinman Low nebula. From a combination of this measurement with others, lower bounds for the gas kinetic temperature and column density of the shocked gas in this region are derived. (Auth.)

  4. Improvements to Host Country Radio Astronomy at Robledo: Another antenna, a new receiver, a new backend

    Science.gov (United States)

    Rizzo, J. R.; García-Miró, G.

    2013-05-01

    NASA hosts three complexes worldwide built for spacecraft tracking, whose sensitive antennas are suitable for radio astronomy. Since more than a decade, INTA has managed guaranteed Spanish time at the complex located in Robledo de Chavela, in the frame of the Host Country Radio Astronomy (HCRA) program. Until now, the vast majority of the scientific results were achieved using a K-band (18 to 26 GHz) receiver, attached to the 70m antenna, and a narrow-band autocorrelator. In the recent years, we have undertaken two large instrumental projects: (1) the incorporation of a second antenna (34m in diameter), working in Q-band (38 to 50 GHz); and (2) the design and construction of a wideband backend, which may operate with both the Q- and K-band receivers, providing instantaneous bandwidths from 100 MHz to 6 GHz, and resolutions from 6 to 200 kHz. The new wideband backend is expanding the HCRA possibilities due its bandwidth, versatility, spectral resolution and stability of the baselines. Its IF processor splits each of the two circular-polarization signals, and downconverts them to four base-band channels, 1.5 GHz width. Two different frequencies may be tuned independently. Digitalisation is done through FPGA-based FFT spectrometers, which may be independently configured. Once end-to-end assembled, the commissioning of the new backend was done using the 34m antenna in Q-band. We report the main characteristics of both the antenna recently incorporated to HCRA, and the wideband backend.

  5. SPHEREx: Science Opportunities for Solar System Astronomy

    Science.gov (United States)

    Lisse, Carey Michael; SPHEREx Science Team

    2018-01-01

    SPHEREx, a mission in NASA's Medium Explorer (MIDEX) program that was selected for Phase A study in August 2017, will perform an all-sky near-infrared spectral survey between 0.75 - 5.0 µm in R = 41 filters, and with R = 135 coverage from 4.2 - 5.0 µm, reaching L ~ 19 (5-sigma).SPHEREx has high potential for solar system science. The 96-band survey will cover the entire sky 4 times over the course of 2 years, including thousands of foreground solar system asteroids, comets, Trojans, and KBOs. By canvassing the entire solar system for 2 years, SPHEREx has the potential not only to achieve a relatively complete sensitivity limited survey of the solar system's bodies, but also some capability to search for variation in these bodies over time.For example, the large legacy dataset of SPHEREx will update the WISE catalogue of asteroid sizes and albedos by providing a spectral survey of tens of thousands of bodies. It will provide spectral classification of hundreds of Trojan asteroids, allowing for direct comparison to the asteroid results. It will extend optical surveys of comet composition by dynamical type to hundreds of objects in the NIR, while determining water/dust/CO/CO2 activity vs distance. SPHEREx will also map in great temporal and spatial detail the zodiacal dust debris disk cloud that these bodies produce, providing an unprecedented level of information concerning the sources and sinks of this material.In this paper, we discuss the data release schedule and some example science studies the planetary astronomy community will be able to access using the SPHEREx database. We also outline existing plans within the SPHEREx team to develop software tools to enable easy access to the data and to conduct catalog searches, and ways in which the community can provide input to the SPHEREx Science Team on scientific studies and data/software requirements for those studies, enabling a large number of scientific studies while finding interesting targets for follow

  6. Solar system radio astronomy at low frequencies

    International Nuclear Information System (INIS)

    Desch, M.D.

    1987-01-01

    The planetary radio-astronomy observations obtained with the two Voyager spacecraft since their launch in 1977 are briefly characterized and illustrated with graphs, diagrams, and sample spectra. Topics addressed include the spacecraft designs and trajectories, the wavelength coverage of the radio instruments, the Io-controlled LF emission of Jupiter, the solar-wind effect on the Saturn kilometric radiation, the Saturn electrostatic discharges, and the use of the clocklike feature of the Uranus emission to measure the planet's rotation period. 23 references

  7. Photographs and Classroom Response Systems in Middle School Astronomy Classes

    Science.gov (United States)

    Lee, Hyunju; Feldman, Allan

    2015-01-01

    In spite of being readily available, photographs have played a minor and passive role in science classes. In our study, we present an active way of using photographs in classroom discussions with the use of a classroom response system (CRS) in middle school astronomy classes to teach the concepts of day-night and seasonal change. In this new…

  8. Solar System Symphony: Combining astronomy with live classical music

    Science.gov (United States)

    Kremer, Kyle; WorldWide Telescope

    2017-01-01

    Solar System Symphony is an educational outreach show which combines astronomy visualizations and live classical music. As musicians perform excerpts from Holst’s “The Planets” and other orchestral works, visualizations developed using WorldWide Telescope and NASA images and animations are projected on-stage. Between each movement of music, a narrator guides the audience through scientific highlights of the solar system. The content of Solar System Symphony is geared toward a general audience, particularly targeting K-12 students. The hour-long show not only presents a new medium for exposing a broad audience to astronomy, but also provides universities an effective tool for facilitating interdisciplinary collaboration between two divergent fields. The show was premiered at Northwestern University in May 2016 in partnership with Northwestern’s Bienen School of Music and was recently performed at the Colburn Conservatory of Music in November 2016.

  9. Global Positioning System receiver evaluation results

    Energy Technology Data Exchange (ETDEWEB)

    Byrne, R.H.

    1993-09-01

    A Sandia project currently uses an outdated Magnavox 6400 Global Positioning System (GPS) receiver as the core of its navigation system. The goal of this study was to analyze the performance of the current GPS receiver compared to newer, less expensive models and to make recommendations on how to improve the performance of the overall navigation system. This paper discusses the test methodology used to experimentally analyze the performance of different GPS receivers, the test results, and recommendations on how an upgrade should proceed. Appendices contain detailed information regarding the raw data, test hardware, and test software.

  10. TRAO Multibeam Receiver System and Key Science Programs

    Science.gov (United States)

    Lee, Youngung

    2017-06-01

    Taeduk Radio Astronomy Observatory (TRAO) is now equipped with a main controling computer with VxWorks operating system, a new receiver system, and a new backend system. The new receiver system(TRAO-SEQUOIA) is equipped with high-performing 16-pixel MMIC pre-amplifiers in a 4x4 array, operating within 85~115 GHz frequency range. The system temperature ranges from 150 K (86~110 GHz) to 450 K (115 GHz). The 2nd IF modules with the narrow band and the 8 channels with 4 FFT spectrometers allow to observe 2 frequencies simultaneously within the 85~100 or 100~115 GHz bands for all 16 pixels of the receiver. Radome replacement was completed successfully as of February 2017. In addition, a new servo system will be installed in 2017 summer. We provide OTF (On-The-Fly) as a main observing mode, and position switching mode is available as well. The backend system (FFT spectrometer) provides the 4096x2 channels with fine velocity resolution of about 0.05 km/sec (15 kHz) per channel, and their full spectra bandwidth is 60 MHz. Beam efficiency of the TRAO was measured to be about 46% - 54% (with less than 2% error) between 86 and 115 GHz bands and pointing errors of the 14m telescope were found be 4.4 arcsec in AZ direction and 6 arcsec in EL direction. Generally, we allocate 18 hours of telescope time a day from January to the middle of May, and from October to December. Three Key Science Programs had been selected in 2015 fall and they are supposed to have higher priority for telescope time.

  11. Fundamental Astronomy

    CERN Document Server

    Karttunen, Hannu; Oja, Heikki; Poutanen, Markku; Donner, Karl Johan

    2007-01-01

    Fundamental Astronomy gives a well-balanced and comprehensive introduction to the topics of classical and modern astronomy. While emphasizing both the astronomical concepts and the underlying physical principles, the text provides a sound basis for more profound studies in the astronomical sciences. The fifth edition of this successful undergraduate textbook has been extensively modernized and extended in the parts dealing with the Milky Way, extragalactic astronomy and cosmology as well as with extrasolar planets and the solar system (as a consequence of recent results from satellite missions and the new definition by the International Astronomical Union of planets, dwarf planets and small solar-system bodies). Furthermore a new chapter on astrobiology has been added. Long considered a standard text for physical science majors, Fundamental Astronomy is also an excellent reference and entrée for dedicated amateur astronomers.

  12. Multistandard Receiver Design for Telemedicine Monitoring System

    Directory of Open Access Journals (Sweden)

    Hongmei Wang

    2018-01-01

    Full Text Available In short-distance wireless communications for telemedicine monitoring, different medical data measurement equipment has different wireless transmission modes. A multistandard receiver is designed that can adapt to different medical data measuring equipment. Using a second-order bandpass sampling for the design of antialiasing filters, two aliasing signals can be separated. Simultaneously, constraint conditions for sampling frequency are not as critical. The design is useful for a multistandard receiver in a telemedicine monitoring system and has the advantages such as saving spectrum resources and facilitating spectrum planning.

  13. Tools of radio astronomy

    CERN Document Server

    Wilson, Thomas L; Hüttemeister, Susanne

    2013-01-01

    This 6th edition of “Tools of Radio Astronomy”, the most used introductory text in radio astronomy, has been revised to reflect the current state of this important branch of astronomy. This includes the use of satellites, low radio frequencies, the millimeter/sub-mm universe, the Cosmic Microwave Background and the increased importance of mm/sub-mm dust emission. Several derivations and presentations of technical aspects of radio astronomy and receivers, such as receiver noise, the Hertz dipole and  beam forming have been updated, expanded, re-worked or complemented by alternative derivations. These reflect advances in technology. The wider bandwidths of the Jansky-VLA and long wave arrays such as LOFAR and mm/sub-mm arrays such as ALMA required an expansion of the discussion of interferometers and aperture synthesis. Developments in data reduction algorithms have been included. As a result of the large amount of data collected in the past 20 years, the discussion of solar system radio astronomy, dust em...

  14. Receiving Assistance and Local Food System Participation

    Directory of Open Access Journals (Sweden)

    Rebecca L. Som Castellano

    2017-02-01

    Full Text Available A body of literature has noted that local food systems (LFSs may not involve active participation by individuals with lower incomes. This is, in part, a function of racial and class hegemony, as well as physical and financial accessibility of LFSs. LFS institutions, such as farmers’ markets, have been working to facilitate receipt of food assistance programs, such as the Supplemental Nutrition Assistance Program (SNAP. Charitable assistance programs, such as food banks, have also been actively working to engage in LFSs, for example, by making local foods available. However, little research has explored the role that receiving public or charitable assistance can play in influencing LFS participation. In this article, I utilize quantitative and qualitative data collected from across the state of Ohio to examine the relationship between receiving assistance and LFS participation for women, who remain predominately responsible for food provisioning in the U.S., including among those who participate in LFSs. Quantitative results suggest that receiving assistance can increase participation in LFSs. Qualitative data provides more nuanced information about the importance of food assistance for women who want to participate in LFSs, and suggest that it is essential that food cooperatives and farmers’ markets are equipped to receive food assistance programs, such as SNAP, in order for women with lower incomes to participate in LFSs.

  15. Superconductor Digital-RF Receiver Systems

    Science.gov (United States)

    Mukhanov, Oleg A.; Kirichenko, Dmitri; Vernik, Igor V.; Filippov, Timur V.; Kirichenko, Alexander; Webber, Robert; Dotsenko, Vladimir; Talalaevskii, Andrei; Tang, Jia Cao; Sahu, Anubhav; Shevchenko, Pavel; Miller, Robert; Kaplan, Steven B.; Sarwana, Saad; Gupta, Deepnarayan

    Digital superconductor electronics has been experiencing rapid maturation with the emergence of smaller-scale, lower-cost communications applications which became the major technology drivers. These applications are primarily in the area of wireless communications, radar, and surveillance as well as in imaging and sensor systems. In these areas, the fundamental advantages of superconductivity translate into system benefits through novel Digital-RF architectures with direct digitization of wide band, high frequency radio frequency (RF) signals. At the same time the availability of relatively small 4K cryocoolers has lowered the foremost market barrier for cryogenically-cooled digital electronic systems. Recently, we have achieved a major breakthrough in the development, demonstration, and successful delivery of the cryocooled superconductor digital-RF receivers directly digitizing signals in a broad range from kilohertz to gigahertz. These essentially hybrid-technology systems combine a variety of superconductor and semiconductor technologies packaged with two-stage commercial cryocoolers: cryogenic Nb mixed-signal and digital circuits based on Rapid Single Flux Quantum (RSFQ) technology, room-temperature amplifiers, FPGA processing and control circuitry. The demonstrated cryocooled digital-RF systems are the world's first and fastest directly digitizing receivers operating with live satellite signals in X-band and performing signal acquisition in HF to L-band at ˜30GHz clock frequencies.

  16. Astronomy essentials

    CERN Document Server

    Brass, Charles O

    2012-01-01

    REA's Essentials provide quick and easy access to critical information in a variety of different fields, ranging from the most basic to the most advanced. As its name implies, these concise, comprehensive study guides summarize the essentials of the field covered. Essentials are helpful when preparing for exams, doing homework and will remain a lasting reference source for students, teachers, and professionals. Astronomy includes the historical perspective of astronomy, sky basics and the celestial coordinate systems, a model and the origin of the solar system, the sun, the planets, Kepler'

  17. Si(Li) detector system for application to x-ray astronomy rocket experiments

    International Nuclear Information System (INIS)

    Griffiths, R.E.; Cheron, C.; Friant, A.; Jehanno, C.; Rocchia, R.; Rothenflug, R.; Testard, O.

    1975-01-01

    The problems associated with the use of Si(Li) detectors in x-ray astronomy rocket experiments are discussed. In particular a detector system is described that can be used at the focus of a grazing-incidence paraboloid telescope for the energy range 0.3 to 2 keV. (U.S.)

  18. Diagrammatic Representational Constraints of Spatial Scale in Earth-Moon System Astronomy Instruction

    Science.gov (United States)

    Taylor, Roger S.; Grundstrom, Erika D.

    2011-01-01

    Given that astronomy heavily relies on visual representations it is especially likely for individuals to assume that instructional materials, such as visual representations of the Earth-Moon system (EMS), would be relatively accurate. However, in our research, we found that images in middle-school textbooks and educational webpages were commonly…

  19. Waste receiving and processing plant control system; system design description

    International Nuclear Information System (INIS)

    LANE, M.P.

    1999-01-01

    The Plant Control System (PCS) is a heterogeneous computer system composed of numerous sub-systems. The PCS represents every major computer system that is used to support operation of the Waste Receiving and Processing (WRAP) facility. This document, the System Design Description (PCS SDD), includes several chapters and appendices. Each chapter is devoted to a separate PCS sub-system. Typically, each chapter includes an overview description of the system, a list of associated documents related to operation of that system, and a detailed description of relevant system features. Each appendice provides configuration information for selected PCS sub-systems. The appendices are designed as separate sections to assist in maintaining this document due to frequent changes in system configurations. This document is intended to serve as the primary reference for configuration of PCS computer systems. The use of this document is further described in the WRAP System Configuration Management Plan, WMH-350, Section 4.1

  20. Waste receiving and processing plant control system; system design description

    Energy Technology Data Exchange (ETDEWEB)

    LANE, M.P.

    1999-02-24

    The Plant Control System (PCS) is a heterogeneous computer system composed of numerous sub-systems. The PCS represents every major computer system that is used to support operation of the Waste Receiving and Processing (WRAP) facility. This document, the System Design Description (PCS SDD), includes several chapters and appendices. Each chapter is devoted to a separate PCS sub-system. Typically, each chapter includes an overview description of the system, a list of associated documents related to operation of that system, and a detailed description of relevant system features. Each appendice provides configuration information for selected PCS sub-systems. The appendices are designed as separate sections to assist in maintaining this document due to frequent changes in system configurations. This document is intended to serve as the primary reference for configuration of PCS computer systems. The use of this document is further described in the WRAP System Configuration Management Plan, WMH-350, Section 4.1.

  1. Optimization of Passive Coherent Receiver System Placement

    Science.gov (United States)

    2013-09-01

    spheroid object with a constant radar cross section (RCS). Additionally, the receiver and transmitters are assumed to be notional isotropic antennae...software- defined radio for equatorial plasma instability studies,” Radio Science, vol. 48, pp. 1–11. Aug. 2013. [2] P. C. Zhang and B. Y. Li, “Passive

  2. Workshop on Satellite Power Systems (SPS) effects on optical and radio astronomy

    International Nuclear Information System (INIS)

    Stokes, G.M.; Ekstrom, P.A.

    1980-04-01

    The impacts of the SPS on astronomy were concluded to be: increased sky brightness, reducing the effective aperture of terrestrial telescopes; microwave leakage radiation causing erroneous radioastronomical signals; direct overload of radioastronomical receivers at centimeter wavelengths; and unintentional radio emissions associated with massive amounts of microwave power or with the presence of large, warm structures in orbit causing the satellites to appear as individual stationary radio sources; finally, the fixed location of the geostationary satellite orbits would result in fixed regions of the sky being unusable for observations

  3. A Desktop Virtual Reality Earth Motion System in Astronomy Education

    Science.gov (United States)

    Chen, Chih Hung; Yang, Jie Chi; Shen, Sarah; Jeng, Ming Chang

    2007-01-01

    In this study, a desktop virtual reality earth motion system (DVREMS) is designed and developed to be applied in the classroom. The system is implemented to assist elementary school students to clarify earth motion concepts using virtual reality principles. A study was conducted to observe the influences of the proposed system in learning.…

  4. Chaco astronomies

    Science.gov (United States)

    Martín López, Alejandro

    2015-08-01

    This presentation discusses the result of 18 years of ethnographic and ethnohistorical studies on Chaco astronomies. The main features of the systems of astronomical knowledge of the Chaco Aboriginal groups will be discussed. In particular we will discuss the relevance of the Milky Way, the role of the visibility of the Pleiades, the ways in which the celestial space is represented, the constitution of astronomical orientations in geographic space, etc. We also address a key feature of their vision of the cosmos: the universe is seen by these groups as a socio-cosmos, where humans and non-humans are related. These are therefore actually socio-cosmologies. We will link this to the theories of Chaco Aboriginal groups about power and political relations.We will discuss how the study of Aboriginal astronomies must be performed along with the studies about astronomies of Creole people and European migrants, as well as anthropological studies about the science teaching in the formal education system and by the mass media. In this form we will discuss the relevance of a very complex system of interethnic relations for the conformation of these astronomical representations and practices.We will also discuss the general methodological implications of this case for the ethnoastronomy studies. In particular we will talk about the advantages of a study of regional scope and about the key importance of put in contact the ethnoastronomy with contemporary issues in social sciences.We also analyze the importance of ethnoastronomy studies in relation to studies of sociology of science, especially astronomy. We also study the potential impact on improving formal and informal science curricula and in shaping effective policies to protect the tangible and intangible astronomical heritage in a context of respect for the rights of Aboriginal groups.

  5. Reviews in Modern Astronomy: Vol. 17: The Sun and Planetary Systems - Paradigms for the Universe

    Science.gov (United States)

    Schielicke, Reinhard E.

    2004-09-01

    Volume 17 continues the Reviews of Modern Astronomy with fourteen invited reviews and Highlight Contributions which were presented during the International Scientific Conference of the Society on "The Sun and Planetary Systems", held at Freiburg, Germany, September 15 to 20, 2003. The Karl Schwarzschild medal 2003 was awarded to Professor Erika Boehm-Vitense, Seattle, USA. Her lecture with the title "What Hyades F Stars tell us about Heating Mechanisms in Stellar Transition Layers and Coronae" opened the meeting. The talk presented by the Ludwig Biermann-Prize winner 2003, Dr Luis R. Bellot Rubio, Freiburg i. Br., Germany, dealt with the topic "The Structure of Sunspots as Inferred from Spectropolarimetric Measurements". Other contributions to the meeting published in this volume discuss, among other subjects, solar physics, formation of planets and interferometric imaging in astronomy.

  6. News Quantum physics: German Physical Society spring meeting Journal access: American Physical Society's online journals will be available for free in all US high schools Award: High-school physics teacher receives American award for excellence Teacher training: Fobinet offers coordination of teacher-training activities Astronomy: Astronomy fans see stars at Astrofest Conference: Delegates enjoy the workshops and activities at CPD conference Forthcoming events

    Science.gov (United States)

    2011-05-01

    Quantum physics: German Physical Society spring meeting Journal access: American Physical Society's online journals will be available for free in all US high schools Award: High-school physics teacher receives American award for excellence Teacher training: Fobinet offers coordination of teacher-training activities Astronomy: Astronomy fans see stars at Astrofest Conference: Delegates enjoy the workshops and activities at CPD conference Forthcoming events

  7. Humanising Astronomy

    Science.gov (United States)

    Levin, S.

    2008-06-01

    Universe Awareness (UNAWE) is an international programme that aims to expose underprivileged children (in the age group 4-10) to the inspirational aspects of astronomy. We are currently at the stage of developing materials that will be utilised in a diverse range of environments. This paper explores UNAWE's particular approach to developing tools which includes not only indigenous and folkloric astronomical knowledge, but also the culture of transmission of such knowledge. A specific understanding and explanation of the Universe, the Sun, Moon and stars is present in every culture and can be found contained in its history, legends and belief systems. By consciously embracing different ways of knowing the Universe and not uniquely the rational model, UNAWE places the humanising potential of astronomy at the centre of its purpose. Whilst inspiring curiosity, pride and a sense of ownership in one's own cultural identity, such an approach also exposes children to the diversity of other peoples and their cultures as well as the unifying aspects of our common scientific heritage. The means of creating and delivering the astronomy programme are as relevant to the desired educational outcomes as the content. The challenge in the design of materials is to communicate this stimulating message to the very young. Respect for alternative values systems, the need for dialogue and community participation, and where possible the production of materials using local resources is emphasised. This paper touches recent experiences liaising with communities in India, South Africa, Tunisia, Venezuela and Colombia.

  8. The Solar System Ballet: A Kinesthetic Spatial Astronomy Activity

    Science.gov (United States)

    Heyer, Inge; Slater, T. F.; Slater, S. J.; Astronomy, Center; Education ResearchCAPER, Physics

    2011-05-01

    The Solar System Ballet was developed in order for students of all ages to learn about the planets, their motions, their distances, and their individual characteristics. To teach people about the structure of our Solar System can be revealing and rewarding, for students and teachers. Little ones (and some bigger ones, too) often cannot yet grasp theoretical and spatial ideas purely with their minds. Showing a video is better, but being able to learn with their bodies, essentially being what they learn about, will help them understand and remember difficult concepts much more easily. There are three segments to this activity, which can be done together or separately, depending on time limits and age of the students. Part one involves a short introductory discussion about what students know about the planets. Then students will act out the orbital motions of the planets (and also moons for the older ones) while holding a physical model. During the second phase we look at the structure of the Solar System as well as the relative distances of the planets from the Sun, first by sketching it on paper, then by recreating a scaled version in the class room. Again the students act out the parts of the Solar System bodies with their models. The third segment concentrates on recreating historical measurements of Earth-Moon-Sun system. The Solar System Ballet activity is suitable for grades K-12+ as well as general public informal learning activities.

  9. Fundamental astronomy

    CERN Document Server

    Kröger, Pekka; Oja, Heikki; Poutanen, Markku; Donner, Karl

    2017-01-01

    Now in its sixth edition this successful undergraduate textbook gives a well-balanced and comprehensive introduction to the topics of classical and modern astronomy. While emphasizing both the astronomical concepts and the underlying physical principles, the text provides a sound basis for more profound studies in the astronomical sciences. The chapters on galactic and extragalactic astronomy as well as cosmology were extensively modernized in the previous edition. In this new edition they have been further revised to include more recent results. The long chapter on the solar system has been split into two parts: the first one deals with the general properties, and the other one describes individual objects. A new chapter on exoplanets has been added to the end of the book next to the chapter on astrobiology. In response to the fact that astronomy has evolved enormously over the last few years, only a few chapters of this book have been left unmodified. Long considered a standard text for physical science maj...

  10. Armenian Cultural Astronomy

    Science.gov (United States)

    Farmanyan, S. V.; Mickaelian, A. M.

    2015-07-01

    Cultural Astronomy is the reflection of sky events in various fields of nations' culture. In foreign literature this field is also called "Astronomy in Culture" or "Astronomy and Culture". Cultural astronomy is the set of interdisciplinary fields studying the astronomical systems of current or ancient societies and cultures. It is manifested in Religion, Mythology, Folklore, Poetry, Art, Linguistics and other fields. In recent years, considerable attention has been paid to this sphere, particularly international organizations were established, conferences are held and journals are published. Armenia is also rich in cultural astronomy. The present paper focuses on Armenian archaeoastronomy and cultural astronomy, including many creations related to astronomical knowledge; calendars, rock art, mythology, etc. On the other hand, this subject is rather poorly developed in Armenia; there are only individual studies on various related issues (especially many studies related to Anania Shirakatsi) but not coordinated actions to manage this important field of investigation.

  11. Initial results for compressive sensing in electronic support receiver systems

    CSIR Research Space (South Africa)

    Du Plessis, WP

    2011-04-01

    Full Text Available determined by the antenna and microwave system comprising the transmitter and receiver, while the instantaneous bandwidth is mainly determined by the Analog-to-Digital Converter (ADC) in the receiver. A radar can thus operate at any frequency within its... Electronic/Electromagnetic Support Measures (ESM) was used historically [1], [2]. Modern ES receiver systems are based on digital receivers allowing powerful signal processing techniques to be used [3], [4]. Recent developments in sampling technology...

  12. A Librarian Without Books:Systems Librarianship in Astronomy

    Science.gov (United States)

    Kneale, R. A.

    2007-10-01

    The author discusses one aspect of the changing nature of librarianship by focusing on a high-tech microcosm of an already high-tech profession, that of systems librarianship. She is the Systems Librarian for the Advanced Technology Solar Telescope (ATST) project, based in Tucson, Arizona. The project is engaged in the design and development of a 4-meter solar telescope, planned for the summit of Haleakalā, Maui, Hawai'i. Most of the day-to-day tasks at ATST involve software in one form or another; the author makes heavy use of Remote Desktop and Virtual Network Computing (VNC) to manage installations on eight different servers (four Windows, four Unix) in two states, plus staff desktops (Windows XP) from the comfy chair in front of her computer.

  13. CANFAR+Skytree: A Cloud Computing and Data Mining System for Astronomy

    Science.gov (United States)

    Ball, N. M.

    2013-10-01

    To-date, computing systems have allowed either sophisticated analysis of small datasets, as exemplified by most astronomy software, or simple analysis of large datasets, such as database queries. At the Canadian Astronomy Data Centre, we have combined our cloud computing system, the Canadian Advanced Network for Astronomical Research (CANFAR), with the world's most advanced machine learning software, Skytree, to create the world's first cloud computing system for data mining in astronomy. CANFAR provides a generic environment for the storage and processing of large datasets, removing the requirement for an individual or project to set up and maintain a computing system when implementing an extensive undertaking such as a survey pipeline. 500 processor cores and several hundred terabytes of persistent storage are currently available to users, and both the storage and processing infrastructure are expandable. The storage is implemented via the International Virtual Observatory Alliance's VOSpace protocol, and is available as a mounted filesystem accessible both interactively, and to all processing jobs. The user interacts with CANFAR by utilizing virtual machines, which appear to them as equivalent to a desktop. Each machine is replicated as desired to perform large-scale parallel processing. Such an arrangement enables the user to immediately install and run the same astronomy code that they already utilize, in the same way as on a desktop. In addition, unlike many cloud systems, batch job scheduling is handled for the user on multiple virtual machines by the Condor job queueing system. Skytree is installed and run just as any other software on the system, and thus acts as a library of command line data mining functions that can be integrated into one's wider analysis. Thus we have created a generic environment for large-scale analysis by data mining, in the same way that CANFAR itself has done for storage and processing. Because Skytree scales to large data in

  14. Joint Transmitter-Receiver Optimization in the Downlink CDMA Systems

    Directory of Open Access Journals (Sweden)

    Mohammad Saquib

    2002-08-01

    Full Text Available To maximize the downlink code-division multiple access (CDMA system capacity, we propose to minimize the total transmitted power of the system subject to users′ signal-to-interference ratio (SIR requirements via designing optimum transmitter sequences and utilizing linear optimum receivers (minimum mean square error (MMSE receiver. In our work on joint transmitter-receiver design for the downlink CDMA systems with multiple antennas and multipath channels, we develop several optimization algorithms by considering various system constraints and prove their convergence. We empirically observed that under the optimization algorithm with no constraint on the system, the optimum receiver structure matches the received transmitter sequences. A simulation study is performed to see how the different practical system constraints penalize the system with respect to the optimum algorithm with no constraint on the system.

  15. Developing a Global Science and Math Education System Based on Real Astronomy Data

    Science.gov (United States)

    Pennypacker, Carlton

    2015-03-01

    Global Hands-On Universe (GHOU) is an educational system where students use real astronomy data from (largely optical) telescopes to learn fundamental physics, math, astronomy, and technology.GHOU is a good example of a collaborative global education project, where data, software, teacher training methods, curriculum, activities, telescopes, and human resources are developed by many members of GHOU and then shared internationally.Assessments show that in this program students learn more science and math than in conventional classroom teaching, and students change their attitudes towards choosing careers in science and technology.GHOU is an exemplar of appropriate use of computers in the classroom for real data analysis.The International Asteroid Search program of GHOU has helped students discover over 700 asteroids. Half a dozen high schools have named the asteroids they have found after their high school (some from here in Texas!).GHOU has found resonance with many teachers and students around the world, reaching approximately 20,000 global teachers in the International Year of Astronomy in 2009.In addition, activities from French HOU are part of the official French National Curriculum, and exit exam, teacher training syllabus and teacher exit exams. GHOU has found particular enthusiasms in nations with increasing technology basis - for example, GHOU is reaching many teachers in China, Chile, Indonesia, Kenya, Venezuela, with expansion plans for Cuba underway. Some nations, such as Portugal, have reached reasonable fractions of their teachers through GHOU. Workshops are planned in Iran, and HOU colleagues are starting to build a GHOU telescope in Israel. US HOU had trained approximately 1000 teachers in the United States, before the closing of the NSF Teacher Enhancement Section.But as many new large and smaller telescopes come on line - e.g., the Large Synoptic Survey Telescope - the need for GHOU around the world and even the United States will only increase.

  16. Intermediate Frequency Digital Receiver Based on Multi-FPGA System

    Directory of Open Access Journals (Sweden)

    Chengchang Zhang

    2016-01-01

    Full Text Available Aiming at high-cost, large-size, and inflexibility problems of traditional analog intermediate frequency receiver in the aerospace telemetry, tracking, and command (TTC system, we have proposed a new intermediate frequency (IF digital receiver based on Multi-FPGA system in this paper. Digital beam forming (DBF is realized by coordinated rotation digital computer (CORDIC algorithm. An experimental prototype has been developed on a compact Multi-FPGA system with three FPGAs to receive 16 channels of IF digital signals. Our experimental results show that our proposed scheme is able to provide a great convenience for the design of IF digital receiver, which offers a valuable reference for real-time, low power, high density, and small size receiver design.

  17. XUV astronomy

    International Nuclear Information System (INIS)

    Beuermann, K.P.; Technische Univ. Berlin

    1980-01-01

    A review is presented of the young field of extreme-ultraviolet astronomy at wavelengths from 50 Angstroem to 912 Angstroem. In recent years, it was realized that observations in this wavelength band could be performed due to the lucky circumstance that the sun is located in an extended region of extremely low interstellar gas density. Hence, the horizon for observations at 100 Angstroem due to the photoelectric opacity of the interstellar medium is typically at a distance of about 200 pc. Since 1975 a series of rocket and satellite observations have yielded the first positive results. Sources which radiate primarily in the extreme ultraviolet have been detected and even the small list of currently observed objects has had immediate impact on the studies of both stellar evolution and the interstellar medium. Diffuse emission from the interstellar medium results from a hot 10 5 to 10 6 K component of the interstellar gas. Prime stellar candidates for extreme-ultraviolet observations are (1) hot low-luminosity stars at the blue end of the HR diagram as, e.g., white dwarfs at the beginning of the cooling sequence, (2) atmospheric emission from stars surrounded by a hot corona or with flaring activity, (3) mass-exchanging binary systems as, e.g., main-sequence close binaries or catalysmic variables. The article discusses the prospects of extreme-ultraviolet astronomy and reviews the existing observations of extreme-ultraviolet emission from the interstellar medium and from stellar sources of the different categories. (orig.)

  18. Handbook of pulsar astronomy

    CERN Document Server

    Lorimer, Duncan

    2005-01-01

    Radio pulsars are rapidly rotating highly magnetized neutron stars. Studies of these fascinating objects have provided applications in solid-state physics, general relativity, galactic astronomy, astrometry, planetary physics and even cosmology. Most of these applications and much of what we know about neutron stars are derived from single-dish radio observations using state-of-the-art receivers and data acquisition systems. This comprehensive 2004 book is a unique resource that brings together the key observational techniques, background information and a review of results, including the discovery of a double pulsar system. Useful software tools are provided which can be used to analyse example data, made available on a related website. This work will be of great value not only to graduate students but also to researchers wishing to carry out and interpret a wide variety of radio pulsar observations.

  19. A first-generation software product line for data acquisition systems in astronomy

    Science.gov (United States)

    López-Ruiz, J. C.; Heradio, Rubén; Cerrada Somolinos, José Antonio; Coz Fernandez, José Ramón; López Ramos, Pablo

    2008-07-01

    This article presents a case study on developing a software product line for data acquisition systems in astronomy based on the Exemplar Driven Development methodology and the Exemplar Flexibilization Language tool. The main strategies to build the software product line are based on the domain commonality and variability, the incremental scope and the use of existing artifacts. It consists on a lean methodology with little impact on the organization, suitable for small projects, which reduces product line start-up time. Software Product Lines focuses on creating a family of products instead of individual products. This approach has spectacular benefits on reducing the time to market, maintaining the know-how, reducing the development costs and increasing the quality of new products. The maintenance of the products is also enhanced since all the data acquisition systems share the same product line architecture.

  20. Flexible Receiver Radiation Detection System (FRRDS) Users Manual

    International Nuclear Information System (INIS)

    Troyer, G.L.

    1996-01-01

    The Flexible Receiver Radiation Detection System (FRRDS) comprises a control computer, a remote data acquisition subsystem, and three hyperpure germanium gamma radiation detectors. The scope of this document is the description of various steps for the orderly start-up, use, and shutdown of the FRRDS. Only those items necessary for these oprations are included. This document is a companion to WHC-SD-W151-UM-002, 'Operating Instructions for the 42 Inch Flexible Receiver,' WHC-SD-W151-UM-003, 'Operating Instructions for the 4-6 Inch Flexible Receiver,' and the vendor supplied system users guide (Ref. 6)

  1. Solar central receiver reformer system for ammonia plants

    Science.gov (United States)

    1980-07-01

    An overview of a study to retrofit the Valley Nitrogen Producers, Inc., El Centro, California 600 ST/SD Ammonia Plant with Solar Central Receiver Technology is presented. The retrofit system consists of a solar central receiver reformer (SCRR) operating in parallel with the existing fossil fired reformer. Steam and hydrocarbon react in the catalyst filled tubes of the inner cavity receiver to form a hydrogen rich mixture which is the syngas feed for the ammonia production. The SCRR system will displace natural gas presently used in the fossil reformer combustion chamber.

  2. Asymmetric Hardware Distortions in Receive Diversity Systems: Outage Performance Analysis

    KAUST Repository

    Javed, Sidrah; Amin, Osama; Ikki, Salama S.; Alouini, Mohamed-Slim

    2017-01-01

    This paper studies the impact of asymmetric hardware distortion (HWD) on the performance of receive diversity systems using linear and switched combining receivers. The asymmetric attribute of the proposed model motivates the employment of improper Gaussian signaling (IGS) scheme rather than the traditional proper Gaussian signaling (PGS) scheme. The achievable rate performance is analyzed for the ideal and non-ideal hardware scenarios using PGS and IGS transmission schemes for different combining receivers. In addition, the IGS statistical characteristics are optimized to maximize the achievable rate performance. Moreover, the outage probability performance of the receive diversity systems is analyzed yielding closed form expressions for both PGS and IGS based transmission schemes. HWD systems that employ IGS is proven to efficiently combat the self interference caused by the HWD. Furthermore, the obtained analytic expressions are validated through Monte-Carlo simulations. Eventually, non-ideal hardware transceivers degradation and IGS scheme acquired compensation are quantified through suitable numerical results.

  3. Asymmetric Hardware Distortions in Receive Diversity Systems: Outage Performance Analysis

    KAUST Repository

    Javed, Sidrah

    2017-02-22

    This paper studies the impact of asymmetric hardware distortion (HWD) on the performance of receive diversity systems using linear and switched combining receivers. The asymmetric attribute of the proposed model motivates the employment of improper Gaussian signaling (IGS) scheme rather than the traditional proper Gaussian signaling (PGS) scheme. The achievable rate performance is analyzed for the ideal and non-ideal hardware scenarios using PGS and IGS transmission schemes for different combining receivers. In addition, the IGS statistical characteristics are optimized to maximize the achievable rate performance. Moreover, the outage probability performance of the receive diversity systems is analyzed yielding closed form expressions for both PGS and IGS based transmission schemes. HWD systems that employ IGS is proven to efficiently combat the self interference caused by the HWD. Furthermore, the obtained analytic expressions are validated through Monte-Carlo simulations. Eventually, non-ideal hardware transceivers degradation and IGS scheme acquired compensation are quantified through suitable numerical results.

  4. Heat receivers for solar dynamic space power systems

    Science.gov (United States)

    Perez-Davis, Marla Esther

    A review of state-of-the-art technology is presented and discussed for phase change materials. Some of the advanced solar dynamic designs developed as part of the Advanced Heat Receiver Conceptual Design Study performed for LeRC are discussed. The heat receivers are analyzed and several recommendations are proposed, including two new concepts. The first concept evaluated the effect of tube geometries inside the heat receiver. It was found that a triangular configuration would provide better heat transfer to the working fluid, although not necessarily with a reduction in receiver size. A sensible heat receiver considered in this study uses vapor grown graphite fiber-carbon (VGCF/C) composite as the thermal storage media and was designed for a 7 kW Brayton engine. The proposed heat receiver stores the required energy to power the system during eclipse in the VGCF/C composite. The heat receiver analysis was conducted through the Systems Improved Numerical Differencing Analyzer and Fluid Integrator (SINDA) software package. The proposed heat receiver compares well with other latent and advanced sensible heat receivers while avoiding the problems associated with latent heat storage salts and liquid metal heat pipes. The weight and size of the system can be optimized by changes in geometry and technology advances for this new material. In addition to the new concepts, the effect of atomic oxygen on several materials is reviewed. A test was conducted for atomic oxygen attack on boron nitride, which experienced a negligible mass loss when exposed to an atomic oxygen fluence of 5 x 10 exp 21 atoms/sq cm. This material could be used to substitute the graphite aperture plate of the heat receiver.

  5. Mathematical Astronomy in India

    Science.gov (United States)

    Plofker, Kim

    Astronomy in South Asia's Sanskrit tradition, apparently originating in simple calendric computations regulating the timing of ancient ritual practices, expanded over the course of two or three millennia to include detailed spherical models, an endless variety of astrological systems, and academic mathematics in general. Assimilating various technical models, methods, and genres from the astronomy of neighboring cultures, Indian astronomers created new forms that were in turn borrowed by their foreign counterparts. Always recognizably related to the main themes of Eurasian geocentric mathematical astronomy, Indian astral science nonetheless maintained its culturally distinct character until Keplerian heliocentrism and Newtonian mechanics replaced it in colonial South Asia's academic mainstream.

  6. Autonomous Integrated Receive System (AIRS) requirements definition. Volume 4: Functional specification for the prototype Automated Integrated Receive System (AIRS)

    Science.gov (United States)

    Chie, C. M.

    1984-01-01

    The functional requirements for the performance, design, and testing for the prototype Automated Integrated Receive System (AIRS) to be demonstrated for the TDRSS S-Band Single Access Return Link are presented.

  7. The road to OLFAR - a roadmap to interferometric long-wavelength radio astronomy using miniaturized distributed space systems

    NARCIS (Netherlands)

    Engelen, Steven; Quillien, Kevin A.; Verhoeven, Chris; Noroozi, Arash; Sundaramoorthy, Prem; van der Veen, Alle-Jan; Rajan, Raj; Rajan, Raj Thilak; Boonstra, Albert Jan; Bentum, Marinus Jan; Meijerink, Arjan; Budianu, A.

    2013-01-01

    The Orbiting Low Frequency Antennas for Radio Astronomy (OLFAR) project aims to develop a space-based low frequency radio telescope that will explore the universe's so-called dark ages, map the interstellar medium, and discover planetary and solar bursts in other solar systems. The telescope,

  8. A Fast Adaptive Receive Antenna Selection Method in MIMO System

    Directory of Open Access Journals (Sweden)

    Chaowei Wang

    2013-01-01

    Full Text Available Antenna selection has been regarded as an effective method to acquire the diversity benefits of multiple antennas while potentially reduce hardware costs. This paper focuses on receive antenna selection. According to the proportion between the numbers of total receive antennas and selected antennas and the influence of each antenna on system capacity, we propose a fast adaptive antenna selection algorithm for wireless multiple-input multiple-output (MIMO systems. Mathematical analysis and numerical results show that our algorithm significantly reduces the computational complexity and memory requirement and achieves considerable system capacity gain compared with the optimal selection technique in the same time.

  9. The Astronomy Workshop

    Science.gov (United States)

    Hamilton, D. P.; Asbury, M. L.; Proctor, A.

    2001-12-01

    The Astronomy Workshop (http://janus.astro.umd.edu) is an interactive online astronomy resource developed, and maintained at the University of Maryland, for use by students, educators and the general public. The Astronomy Workshop has been extensively tested and used successfully at many different levels, including High School and Junior High School science classes, University introductory astronomy courses, and University intermediate and advanced astronomy courses. Some topics currently covered in the Astronomy Workshop are: Animated Orbits of Planets and Moons: The orbits of the nine planets and 91 known planetary satellites are shown in animated, to-scale drawings. The orbiting bodies move at their correct relative speeds about their parent, which is rendered as an attractive, to-scale gif image. Solar System Collisions: This most popular of our applications shows what happens when an asteroid or comet with user-defined size and speed impacts a given planet. The program calculates many effects, including the country impacted (if Earth is the target), energy of the explosion, crater size, magnitude of the planetquake generated. It also displays a relevant image (e.g. terrestrial crater, lunar crater, etc.). Planetary and Satellite Data Calculators: These tools allow the user to easily calculate physical data for all of the planets or satellites simultaneously, making comparison very easy. Orbital Simulations: These tools allow the student to investigate different aspects of the three-body problem of celestial mechanics. Astronomy Workshop Bulletin Board: Get innovative teaching ideas and read about in-class experiences with the Astronomy Workshop. Share your ideas with other educators by posting on the Bulletin Board. Funding for the Astronomy Workshop is provided by the National Science Foundation.

  10. Astronomy Landscape in Africa

    Science.gov (United States)

    Nemaungani, Takalani

    2015-01-01

    The vision for astronomy in Africa is embedded in the African Space Policy of the African Union in early 2014. The vision is about positioning Africa as an emerging hub for astronomy sciences and facilities. Africa recognized the need to take advantage of its natural resource, the geographical advantage of the clear southern skies and pristine sites for astronomy. The Pan African University (PAU) initiative also presents an opportunity as a post-graduate training and research network of university nodes in five regions of Africa and supported by the African Union. The Southern African node based in South Africa concentrates on space sciences which also includes astronomy. The PAU aims to provide the opportunity for advanced graduate training and postgraduate research to high-performing African students. Objectives also include promoting mobility of students and teachers and harmonizing programs and degrees.A number of astronomy initiatives have burgeoned in the Southern African region and these include the Southern Africa Largest Optical Telescope (SALT), HESS (High Energy Stereoscopic System), the SKA (Square Kilometre Array) and the AVN (African Very Long Baseline Interferometer Network). There is a growing appetite for astronomy sciences in Africa. In East Africa, the astronomy community is well organized and is growing - the East African Astronomical society (EAAS) held its successful fourth annual conference since 2010 on 30 June to 04 July 2014 at the University of Rwanda. Centred around the 'Role of Astronomy in Socio-Economic Transformation,' this conference aimed at strengthening capacity building in Astronomy, Astrophysics and Space Science in general, while providing a forum for astronomers from the region to train young and upcoming scientists.

  11. Performance Evaluation of Irbene RT-16 Radio Telescope Receiving System

    Directory of Open Access Journals (Sweden)

    Bleiders M.

    2017-12-01

    Full Text Available In the present paper, recent measurement results of refurbished Irbene RT-16 radio telescope receiving system performance are presented. The aim of the research is to evaluate characteristics of RT-16, which will allow carrying out necessary amplitude calibration in both single dish and VLBI observations, to improve the performance of existing system as well as to monitor, control and compare performance if possible changes in the receiving system will occur in future. The evaluated receiving system is 16 m Cassegrain antenna equipped with a cryogenic receiver with frequency range from 4.5 to 8.8 GHz, which is divided into four sub-bands. Multiple calibration sessions have been carried out by observing stable astronomical sources with known flux density by using in-house made total power registration backend. First, pointing offset calibration has been carried out and pointing model coefficients calculated and applied. Then, amplitude calibration, namely antenna sensitivity, calibration diode equivalent flux density and gain curve measurements have been carried out by observing calibration sources at different antenna elevations at each of the receiver sub-bands. Beam patterns have also been evaluated at different frequency bands. As a whole, acquired data will serve as a reference point for comparison in future performance evaluation of RT-16.

  12. Solar central receiver reformer system for ammonia plants

    Science.gov (United States)

    1980-07-01

    Details of the conceptual design, economic analysis, and development plan for a solar central receiver system for retrofitting the Valley Nitrogen Producers, Inc., El Centro, California 600 ST/SD Ammonia Plant are presented. The retrofit system consists of a solar central receiver reformer (SCRR) operating in parallel with the existing fossil fired reformer. Steam and hydrocarbon react in the catalyst filled tubes of the inner cavity receiver to form a hydrogen rich mixture which is the syngas feed for the ammonia production. The SCRR system displaces natural gas presently used in the fossil reformer combustion chamber. The solar reformer retrofit system characteristics and its interface with the existing plant are simple, incorporating state of the art components with proven technology. A northfield composed of one thousand forty second generation heliostats provides solar energy to the receiver which is positioned on top of a 90 meter high steel tower. The overall economics of this system can provide over 20% discount cash flow rate of return with proper investment and market conditions.

  13. Greek astronomy

    CERN Document Server

    Heath, Sir Thomas L

    2011-01-01

    Astronomy as a science began with the Ionian philosophers, with whom Greek philosophy and mathematics also began. While the Egyptians and Babylonians had accomplished much of astronomical worth, it remained for the unrivalled speculative genius of the Greeks, in particular, their mathematical genius, to lay the foundations of the true science of astronomy. In this classic study, a noted scholar discusses in lucid detail the specific advances made by the Greeks, many of whose ideas anticipated the discoveries of modern astronomy.Pythagoras, born at Samos about 572 B.C., was probably the first

  14. Study on UF6 condensing receiving system improvement

    International Nuclear Information System (INIS)

    Zhang Zhenxing; Li Yingfeng; Li Zhenfeng; He Ping; Wang Yanping; Tian Yushan

    2012-01-01

    In order to improve receiving capacity of UF 6 condensing system, the pressure release mode is changed through modifying gas phase inlet of the first-grade condenser, thus pressure release time is reduced from 13.1 h to 8.1 h. Be- cause of improvement of utility condensers of the two product lines, both the flexibility of feeding nitrogen and the emergency capacity of condensers are improved greatly. And modification of fluid transferring and sampling system make the remains in system transfer flexibly. The practise shows that metal direct recovery rises to the extent, and capacity of the first-grade condensing receiving system improves 8.4%, which strongly guarantees fluorination production safely, continuously and stably run. (authors)

  15. Gamma astronomy

    International Nuclear Information System (INIS)

    Cesarsky, C.; Cesarsky, J.P.

    1986-01-01

    This article overviews the gamma astronomy research. Sources already observed, and what causes to give to them; the galactic radiation and its interpretation; techniques already used and current projects [fr

  16. Accessible Astronomy.

    Science.gov (United States)

    Glickstein, Neil

    1994-01-01

    Describes the development of a theme-based, multidisciplinary course. The article partitions into the following sections: (1) Constructing the Course; (2) Putting the Ideas to Work; (3) Connecting Science and Society; and (4) The Arts and Astronomy. (ZWH)

  17. Astronomy Communication

    Science.gov (United States)

    Heck, A.; Madsen, C.

    2003-07-01

    Astronomers communicate all the time, with colleagues of course, but also with managers and administrators, with decision makers and takers, with social representatives, with the news media, and with the society at large. Education is naturally part of the process. Astronomy communication must take into account several specificities: the astronomy community is rather compact and well organized world-wide; astronomy has penetrated the general public remarkably well with an extensive network of associations and organizations of aficionados all over the world. Also, as a result of the huge amount of data accumulated and by necessity for their extensive international collaborations, astronomers have pioneered the development of distributed resources, electronic communications and networks coupled to advanced methodologies and technologies, often much before they become of common world-wide usage. This book is filling up a gap in the astronomy-related literature by providing a set of chapters not only of direct interest to astronomy communication, but also well beyond it. The experts contributing to this book have done their best to write in a way understandable to readers not necessarily hyperspecialized in astronomy nor in communication techniques while providing specific detailed information, as well as plenty of pointers and bibliographic elements. This book will be very useful for researchers, teachers, editors, publishers, librarians, computer scientists, sociologists of science, research planners and strategists, project managers, public-relations officers, plus those in charge of astronomy-related organizations, as well as for students aiming at a career in astronomy or related space science. Link: http://www.wkap.nl/prod/b/1-4020-1345-0

  18. Radio astronomy

    International Nuclear Information System (INIS)

    Parijskij, Y.N.; Gossachinskij, I.V.; Zuckerman, B.; Khersonsky, V.K.; Pustilnik, S.; Robinson, B.J.

    1976-01-01

    A critical review of major developments and discoveries in the field of radioastronomy during the period 1973-1975 is presented. The report is presented under the following headings:(1) Continuum radiation from the Galaxy; (2) Neutral hydrogen, 21 cm (galactic and extragalactic) and recombination lines; (3) Radioastronomy investigations of interstellar molecules; (4) Extragalactic radio astronomy and (6) Development in radio astronomy instruments. (B.R.H.)

  19. Fundamental Astronomy and Solar System Dynamics : Invited Papers Honoring Prof. Walter Fricke on the occasion of his 70th birthday

    CERN Document Server

    Lieske, J; Seidelmann, P

    1986-01-01

    "Fundamental Astronomy and Solar System Dynamics", a program of invited papers honoring Professor Walter Fricke, who for thirty years has been Director of the Astronomisches Rechen lnstitut in Heidelberg, was held at the Thompson Conference Center of the University of Texas at Austin on Wednesday 27 March 1985 on the occasion of his seventieth birthday and retirement as Director of ARl. Professor Fricke's contributions to astronomy encompass the areas of galactic dynamics, radial velocities, stellar statistics. the fundamental reference system and the constant of precession. Participants were welcomed to the Uni versi ty of Texas by Professor J. Parker Lamb, Chairman of the Department of Aerospace Engineering and Engineering Mechanics. The presentations ranged from discussions of astrometric problems concerned with the reference system, the constant of precession, major and minor planet observations, planetary ephemerides and lunar and satellite laser ranging, to a study of disc galaxies in massive halos. The...

  20. A heat receiver design for solar dynamic space power systems

    Science.gov (United States)

    Baker, Karl W.; Dustin, Miles O.; Crane, Roger

    1990-01-01

    An advanced heat pipe receiver designed for a solar dynamic space power system is described. The power system consists of a solar concentrator, solar heat receiver, Stirling heat engine, linear alternator and waste heat radiator. The solar concentrator focuses the sun's energy into a heat receiver. The engine and alternator convert a portion of this energy to electric power and the remaining heat is rejected by a waste heat radiator. Primary liquid metal heat pipes transport heat energy to the Stirling engine. Thermal energy storage allows this power system to operate during the shade portion of an orbit. Lithium fluoride/calcium fluoride eutectic is the thermal energy storage material. Thermal energy storage canisters are attached to the midsection of each heat pipe. The primary heat pipes pass through a secondary vapor cavity heat pipe near the engine and receiver interface. The secondary vapor cavity heat pipe serves three important functions. First, it smooths out hot spots in the solar cavity and provides even distribution of heat to the engine. Second, the event of a heat pipe failure, the secondary heat pipe cavity can efficiently transfer heat from other operating primary heat pipes to the engine heat exchanger of the defunct heat pipe. Third, the secondary heat pipe vapor cavity reduces temperature drops caused by heat flow into the engine. This unique design provides a high level of reliability and performance.

  1. Submillimetre-wave astronomy

    International Nuclear Information System (INIS)

    Beckman, J.E.; Phillips, J.P.

    1982-01-01

    Observations in the 100-1000-micron band and the instruments used to obtain them are discussed in contributions to the Submillimeter Wave Astronomy Conference held at Queen Mary College, London, in September 1981. The major subject areas covered are large-scale structure and radiative transfer within interstellar clouds, spectroscopic observations of molecular sources, interstellar chemistry, and submillimeter (SM) instrumentation. Reports are included on the formation of giant cloud complexes, cool molecular clouds, models for hot-centered and externally heated clouds, dust in Bok globules, airborne FIR and SM spectroscopy, rotational transitions of CH3OH and NH2 near 1.2 mm, high-velocity flows and molecular jets, FIR emissions from late-type galaxies, ion-grain collisions as a source of interstellar molecules, bandpass filters for SM astronomy, the SM receiver of the future, HF techniques in heterodyne astronomy, and the mm-wave cosmic background

  2. Solar system astronomy with the 3.6-m DOT and the 4-m ILMT

    Science.gov (United States)

    Ganesh, Shashikiran; Venkataramani, Kumar; Baliyan, Kiran Singh; Joshi, Umesh Chandra

    2018-04-01

    Solar system astronomy would be an important field of study with the 3.6-m Devasthal Optical Telescope (DOT) and the 4-m International Liquid Mirror Telescope (ILMT). In this contribution, we highlight the work that could be done in reaching a better understanding of the Solar system and its constituents - particularly the minor bodies and other smaller objects. There may be a large number of very faint objects in the vicinity of the Earth orbit. In fact only recently a 'second moon' of the Earth has been found and has been designated 2016 H03. This is a quasi-satellite with the same period of revolution around Earth and Sun. There could be many such objects and it is important to have a full characterization and understanding of these potentially hazardous objects. They are generally fainter than 18th magnitude and one would need a lot of telescope time to fully characterize these objects using techniques of spectropolarimetry. In a similar fashion, a deep census of the Kuiper Belt Objects and the TNOs is needed. In this census, the concept of pencil beam surveys could be extended to cylindrical transit imaging technique available with the 4-m ILMT.

  3. Note: Optical receiver system for 152-channel magnetoencephalography

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jin-Mok; Kwon, Hyukchan; Yu, Kwon-kyu; Lee, Yong-Ho; Kim, Kiwoong [Center for Biosignals, Korea Research Institute of Standards and Science, Daejeon 305-600 (Korea, Republic of)

    2014-11-15

    An optical receiver system composing 13 serial data restore/synchronizer modules and a single module combiner converted optical 32-bit serial data into 32-bit synchronous parallel data for a computer to acquire 152-channel magnetoencephalography (MEG) signals. A serial data restore/synchronizer module identified 32-bit channel-voltage bits from 48-bit streaming serial data, and then consecutively reproduced 13 times of 32-bit serial data, acting in a synchronous clock. After selecting a single among 13 reproduced data in each module, a module combiner converted it into 32-bit parallel data, which were carried to 32-port digital input board in a computer. When the receiver system together with optical transmitters were applied to 152-channel superconducting quantum interference device sensors, this MEG system maintained a field noise level of 3 fT/√Hz @ 100 Hz at a sample rate of 1 kSample/s per channel.

  4. A 200kW central receiver CPV system

    Energy Technology Data Exchange (ETDEWEB)

    Lasich, John, E-mail: jbl@raygen.com; Thomas, Ian, E-mail: ithomas@raygen.com; Hertaeg, Wolfgang; Shirley, David; Faragher, Neil; Erenstrom, Neil; Carter, Sam; Cox, Brian; Zuo, Xinyi [Raygen Resources Pty. Ltd., 15 King Street, Blackburn, Victoria, 3130 (Australia)

    2015-09-28

    Raygen Resources has recently completed a Central Receiver CPV (CSPV) pilot plant in Central Victoria, Australia. The system is under final commissioning and initial operation is expected in late April 2015. The pilot demonstrates a full scale CSPV repeatable unit in a form that is representative of a commercial product and provides a test bed to prove out performance and reliability of the CSPV technology. Extensive testing of the system key components: dense array module, wireless solar powered heliostat and control system has been performed in the laboratory and on sun. Results from this key component testing are presented herein.

  5. Automatic Identification System modular receiver for academic purposes

    Science.gov (United States)

    Cabrera, F.; Molina, N.; Tichavska, M.; Araña, V.

    2016-07-01

    The Automatic Identification System (AIS) standard is encompassed within the Global Maritime Distress and Safety System (GMDSS), in force since 1999. The GMDSS is a set of procedures, equipment, and communication protocols designed with the aim of increasing the safety of sea crossings, facilitating navigation, and the rescue of vessels in danger. The use of this system not only is increasingly attractive to security issues but also potentially creates intelligence products throughout the added-value information that this network can transmit from ships on real time (identification, position, course, speed, dimensions, flag, among others). Within the marine electronics market, commercial receivers implement this standard and allow users to access vessel-broadcasted information if in the range of coverage. In addition to satellite services, users may request actionable information from private or public AIS terrestrial networks where real-time feed or historical data can be accessed from its nodes. This paper describes the configuration of an AIS receiver based on a modular design. This modular design facilitates the evaluation of specific modules and also a better understanding of the standard and the possibility of changing hardware modules to improve the performance of the prototype. Thus, the aim of this paper is to describe the system's specifications, its main hardware components, and to present educational didactics on the setup and use of a modular and terrestrial AIS receiver. The latter is for academic purposes and in undergraduate studies such as electrical engineering, telecommunications, and maritime studies.

  6. Active polarization imaging system based on optical heterodyne balanced receiver

    Science.gov (United States)

    Xu, Qian; Sun, Jianfeng; Lu, Zhiyong; Zhou, Yu; Luan, Zhu; Hou, Peipei; Liu, liren

    2017-08-01

    Active polarization imaging technology has recently become the hot research field all over the world, which has great potential application value in the military and civil area. By introducing active light source, the Mueller matrix of the target can be calculated according to the incident light and the emitted or reflected light. Compared with conventional direct detection technology, optical heterodyne detection technology have higher receiving sensitivities, which can obtain the whole amplitude, frequency and phase information of the signal light. In this paper, an active polarization imaging system will be designed. Based on optical heterodyne balanced receiver, the system can acquire the horizontal and vertical polarization of reflected optical field simultaneously, which contain the polarization characteristic of the target. Besides, signal to noise ratio and imaging distance can be greatly improved.

  7. Novel calibration system with sparse wires for CMB polarization receivers

    Energy Technology Data Exchange (ETDEWEB)

    Tajima, O.; /KEK, Tsukuba /Chicago U., KICP; Nguyen, H.; /Fermilab; Bischoff, C.; /Chicago U., KICP /Harvard-Smithsonian Ctr. Astrophys.; Brizius, A.; Buder, I.; Kusaka, A. /Chicago U., KICP

    2011-07-01

    B-modes in the cosmic microwave background (CMB) polarization is a smoking gun signature of the inflationary universe. To achieve better sensitivity to this faint signal, CMB polarization experiments aim to maximize the number of detector elements, resulting in a large focal plane receiver. Detector calibration of the polarization response becomes essential. It is extremely useful to be able to calibrate 'simultaneously' all detectors on the large focal plane. We developed a novel calibration system that rotates a large 'sparse' grid of metal wires, in front of and fully covering the field of view of the focal plane receiver. Polarized radiation is created via the reflection of ambient temperature from the wire surface. Since the detector has a finite beam size, the observed signal is smeared according to the beam property. The resulting smeared polarized radiation has a reasonable intensity (a few Kelvin or less) compared to the sky temperature ({approx}10 K observing condition). The system played a successful role for receiver calibration of QUIET, a CMB polarization experiment located in the Atacama desert in Chile. The successful performance revealed that this system is applicable to other experiments based on different technologies, e.g. TES bolometers.

  8. Novel calibration system with sparse wires for CMB polarization receivers

    International Nuclear Information System (INIS)

    Tajima, O.; Nguyen, H.; Bischoff, C.; Brizius, A.; Buder, I.; Kusaka, A.

    2011-01-01

    B-modes in the cosmic microwave background (CMB) polarization is a smoking gun signature of the inflationary universe. To achieve better sensitivity to this faint signal, CMB polarization experiments aim to maximize the number of detector elements, resulting in a large focal plane receiver. Detector calibration of the polarization response becomes essential. It is extremely useful to be able to calibrate 'simultaneously' all detectors on the large focal plane. We developed a novel calibration system that rotates a large 'sparse' grid of metal wires, in front of and fully covering the field of view of the focal plane receiver. Polarized radiation is created via the reflection of ambient temperature from the wire surface. Since the detector has a finite beam size, the observed signal is smeared according to the beam property. The resulting smeared polarized radiation has a reasonable intensity (a few Kelvin or less) compared to the sky temperature (∼10 K observing condition). The system played a successful role for receiver calibration of QUIET, a CMB polarization experiment located in the Atacama desert in Chile. The successful performance revealed that this system is applicable to other experiments based on different technologies, e.g. TES bolometers.

  9. Astronomy Explained

    Science.gov (United States)

    North, Gerald

    Every year large numbers of people take up the study of astronomy, mostly at amateur level. There are plenty of elementary books on the market, full of colourful photographs, but lacking in proper explanations of how and why things are as they are. Many people eventually wish to go beyond the 'coffee-table book' stage and study this fascinating subject in greater depth. This book is written for them. In addition, many people sit for public examinations in this subject each year and this book is also intended to be of use to them. All the topics from the GCSE syllabus are covered here, with sample questions at the end of each chapter. Astronomy Explained provides a comprehensive treatment of the subject in more depth than is usually found in elementary works, and will be of interest to both amateur astronomers and students of astronomy.

  10. THE ANALYSIS OF SEWAGE SYSTEM INFLUENCE ON RECEIVERS

    Directory of Open Access Journals (Sweden)

    Kamil Pluta

    2015-11-01

    Full Text Available Reducing waste water discharges to the receiver is now one of the most important activities to ensure the protection of surface waters. This is caused mainly by progressive urbanization and increasing impervious surfaces. Discharge of sewage with a large load of pollutants affect the receivers in a negative way. The quality of waste water varies and depends on many factors, but above all, it is closely linked with sewer system applied to the drainage catchment. The article presents a comparative analysis of the environmental impact of three basic sewer systems: combined, separate and semi-separate. The analysis was performed for a typical urban catchment, using the average concentration of the basic indicators of pollution, which total suspended solids, nitrogen and phosphorus, COD, BOD5, selected heavy metals are merked. The results concluded that each of these sewer systems characterized by varying environmental impacts depending on the indicator of pollution. The best of today available technical solutions seem to be semi-separate sewer system, using the storage tank with the control in real time (RTC for controlling the flow.

  11. Solar central receiver hybrid power system. Phase I study

    Energy Technology Data Exchange (ETDEWEB)

    None

    1978-11-01

    A management plan is presented for implementation during the Solar Central Receiver Hybrid Power System - Phase I study project. The project plan and the management controls that will be used to assure technically adequate, timely and cost effective performance of the work required to prepare the designated end products are described. Bechtel in-house controls and those to be used in directing the subcontractors are described. Phase I of the project consists of tradeoff studies, parametric analyses, and engineering studies leading to conceptual definition and evaluation of a commercial hybrid power system that has the potential for supplying economically competitive electric power to a utility grid in the 1985-1990 time frame. The scope also includes the preparation of a development plan for the resolution of technical uncertainties and the preparation of plans and a proposal for Phase II of the program. The technical approach will be based on a central receiver solar energy collection scheme which supplies thermal energy to a combined cycle, generating system, consisting of a gas turbine cycle combined with a steam bottoming cycle by means of a heat recovery steam generator.

  12. Rescuing Middle School Astronomy

    Science.gov (United States)

    Mayo, L. A.; Janney, D.

    2010-12-01

    There is a crisis in education at the middle school level (Spellings, 2006). Recent studies point to large disparities in middle school performance in schools with high minority populations. The largest disparities exist in areas of math and science. Astronomy has a universal appeal for K-12 students but is rarely taught at the middle school level. When it is taught at all it is usually taught in isolation with few references in other classes such as other sciences (e.g. physics, biology, and chemistry), math, history, geography, music, art, or English. The problem is greatest in our most challenged school districts. With scores in reading and math below national averages in these schools and with most state achievement tests ignoring subjects like astronomy, there is little room in the school day to teach about the world outside our atmosphere. Add to this the exceedingly minimal training and education in astronomy that most middle school teachers have and it is a rare school that includes any astronomy teaching at all. In this presentation, we show how to develop and offer an astronomy education training program for middle school teachers encompassing a wide range of educational disciplines that are frequently taught at the middle school level. The prototype for this program was developed and launched in two of the most challenged and diverse school systems in the country; D.C. Public Schools, and Montgomery County (MD) Public Schools.

  13. Using Visual Assessments and Tutorials to Teach Solar System Concepts in Introductory Astronomy

    Science.gov (United States)

    LoPresto, Michael C.

    2010-01-01

    Visual assessments and tutorials are instruments that rely on student construction and/or examination of pictures and/or diagrams rather than multiple choice and/or short answer questions. Being a very visual subject, astronomy lends itself to assessments and tutorials of this type. What follows is a report on the results of the use of visual…

  14. Lithuanian Astronomy

    Science.gov (United States)

    Sudzius, J.; Murdin, P.

    2002-01-01

    Lithuanian folklore, archaic calendars and terminology show that Lithuanians were interested in astronomy from ancient times. A lot of celestial bodies have names of Lithuanian origin that are not related to widely accepted ancient Greek mythology. For example, the Milky Way is named `Pauksciu Takas' (literally the way of birds), the constellation of the Great Bear `Didieji Grizulo Ratai' (literal...

  15. γ astronomy

    International Nuclear Information System (INIS)

    Wolfendale, A.W.

    1987-01-01

    Some problems of gamma astronomy are discussed in the popular form. The most interesting research directions are considered:e + e - pair annihilation, 100 MeV gamma quanta sources, Cherenkov radiation gamma quanta recording and cosmic ray anisotropy. Special attention is paid to unique gamma quanta source - Cygnus X-3. The source possesses the highest luminosity in the gamma range

  16. Radio astronomy

    International Nuclear Information System (INIS)

    1985-01-01

    It is shown how some of the main areas of current CSIRO radioastronomy research are contributing to increasing our knowledge of the universe. The survey includes background astronomy, interstellar gas, the Sun, exploding stars and pulsars, galaxies and quasars. The Australia Telescope and other CSIRO research programs are described

  17. Astronomy and Poetry (overview)

    Science.gov (United States)

    Samvelyan, David

    2016-12-01

    Through this work we have tried to show how astronomy penetrates into the poetry of different periods in time and in various poets' works all over the world. The following work has significant cognitive value, demonstrates and reveals the general nature of certain poets' astronomical ideas and provides a brief analysis in some cases. As a result, we have come to the conclusion that astronomy with all its components such as the sky, our solar system and phenomena such as these have always been a source of inspiration for those who create works of art, moreover some of them have even gained actual astronomical knowledge.

  18. CIAO: A Modern Data Analysis System for X-Ray Astronomy

    Science.gov (United States)

    Fruscione, Antonella

    2017-08-01

    It is now eighteen years after launch and Chandra continues to produce spectacular results!A portion of the success is to be attributed to the data analysis software CIAO (Chandra Interactive Analysis of Observations) that the Chandra X-Ray Center (CXC) continues to improve and release year after year.CIAO is downloaded more than 1200 times a year and it is used by a wide variety of users around the world: from novice to experienced X-ray astronomers, high school, undergraduate and graduate students, archival users (many new to X-ray or Chandra data), users with extensive resources and others from smaller countries and institutions.The scientific goals and kinds of datasets and analysis cover a wide range: observations spanning from days to years, different instrument configurations and different kinds of targets, from pointlike stars and quasars, to fuzzy galaxies and clusters, to moving solar objects. These different needs and goals require a variety of specialized software and careful and detailed documentation which is what the CIAO software provides. In general, we strive to build a software system which is easy for beginners, yet powerful for advanced users.The complexity of the Chandra data require a flexible data analysis system which provides an environment where the users can apply our tools, but can also explore and construct their own applications. The main purpose of this talk is to present CIAO as a modern data analysis system for X-ray data analysis.CIAO has grown tremendously over the years and we will highlight (a) the most recent advancements with a particular emphasis on the newly developed high-level scripts which simplify the analysis steps for the most common cases making CIAO more accessible to all users - including beginners and users who are not X-ray astronomy specialists, (b) the python-based Sherpa modelling and fitting application and the new stand-alone version openly developed and distributed on Github and (c) progress on methods to

  19. Conceptual design of advanced central receiver power systems sodium-cooled receiver concept. Volume 2, Book 2. Appendices. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1979-03-01

    The appendices include: (A) design data sheets and P and I drawing for 100-MWe commercial plant design, for all-sodium storage concept; (B) design data sheets and P and I drawing for 100-MWe commercial plant design, for air-rock bed storage concept; (C) electric power generating water-steam system P and I drawing and equipment list, 100-MWe commercial plant design; (D) design data sheets and P and I drawing for 281-MWe commercial plant design; (E) steam generator system conceptual design; (F) heat losses from solar receiver surface; (G) heat transfer and pressure drop for rock bed thermal storage; (H) a comparison of alternative ways of recovering the hydraulic head from the advanced solar receiver tower; (I) central receiver tower study; (J) a comparison of mechanical and electromagnetic sodium pumps; (K) pipe routing study of sodium downcomer; and (L) sodium-cooled advanced central receiver system simulation model. (WHK)

  20. Communications Satellite Receiver Systems for Public Schools: A Technical Primer.

    Science.gov (United States)

    Texas Education Agency, Austin.

    Designed to aid school districts contemplating use of some of the telecommunications services now available by satellite, this document contains information on home satellite receiving dishes (Television Receive-Only--TVROs), which can receive radio signals carrying television, sound, and data. This information includes: some factors involved in…

  1. Extragalactic astronomy

    International Nuclear Information System (INIS)

    Sersic, J.L.

    1982-01-01

    This book condenses the author's yearly semester lectures on 'Extra galactic Astronomy' held almost without interruption over two decades at Cordoba University for students of Astronomy. After a first chapter on Morphology and Classification of galaxies, the second gives most of the basic information about normal galaxies as individuals. Active galaxies are described in chapter III whilst chapter IV deals with the mutual relationship between galaxies and their environment. The Scale of distance is considered in chapter V. Distance indicators are introduced and several conflicting viewpoints of different schools are presented. Chapter VI deals with Cosmology, just to give the necessary elements for chapter VII where the relation between gravitational instability and galaxy formation is discussed. Chapter VIII is an appendix containing additional notes. (Auth.)

  2. Inuit Astronomy

    Science.gov (United States)

    MacDonald, John

    Inuit live mainly in the treeless Arctic regions of North America, Greenland, and parts of northeastern Siberia. Their cosmology, based on shamanistic belief, constructed a view of the sky and its contents distinctively suited to their spiritual and pragmatic needs. Their astronomy, particularly for those groups living far above the Arctic Circle, reflects the unique appearance of the celestial sphere at high northerly latitudes, demonstrated most noticeably in the annual disappearance of the sun during midwinter months.

  3. Infrared astronomy

    International Nuclear Information System (INIS)

    Setti, G.; Fazio, G.

    1978-01-01

    This volume contains lectures describing the important achievements in infrared astronomy. The topics included are galactic infrared sources and their role in star formation, the nature of the interstellar medium and galactic structure, the interpretation of infrared, optical and radio observations of extra-galactic sources and their role in the origin and structure of the universe, instrumental techniques and a review of future space observations. (C.F.)

  4. The Astronomy of Africa's Health Systems Literature During the MDG Era: Where Are the Systems Clusters?

    Science.gov (United States)

    Phillips, James F; Sheff, Mallory; Boyer, Christopher B

    2015-09-01

    Growing international concern about the need for improved health systems in Africa has catalyzed an expansion of the health systems literature. This review applies a bibliometric procedure to analyze the acceleration of scientific writing on this theme. We focus on research published during the Millennium Development Goal (MDG) era between 1990 and 2014, reporting findings from a systematic review of a database comprised of 17,655 articles about health systems themes from sub-Saharan African countries or subregions. Using bibliometric tools for co-word textual analysis, we analyzed the incidence and associations of keywords and phrases to generate and visualize topical foci on health systems as clusters of themes, much in the manner that astronomers represent groupings of stars as galaxies of celestial entities. The association of keywords defines their relative position, with the size of images weighted by the relative frequency of terms. Sets of associated keywords are arrayed as stars that cluster as "galaxies" of concepts in the knowledge universe represented by health systems research from sub-Saharan Africa. Results show that health systems research is dominated by literature on diseases and categorical systems research topics, rather than on systems science that cuts across diseases or specific systemic themes. Systems research is highly developed in South Africa but relatively uncommon elsewhere in the region. "Black holes" are identified by searching for terms in our keyword library related to terms in widely cited reviews of health systems. Results identify several themes that are unexpectedly uncommon in the country-specific health systems literature. This includes research on the processes of achieving systems change, the health impact of systems strengthening, processes that explain the systems determinants of health outcomes, or systematic study of organizational dysfunction and ways to improve system performance. Research quantifying the relationship

  5. Tools of radio astronomy

    CERN Document Server

    Wilson, Thomas L; Hüttemeister, Susanne

    2009-01-01

    The recent years have seen breathtaking progress in technology, especially in the receiver and digital technologies relevant for radio astronomy, which has at the same time advanced to shorter wavelengths. This is the updated and completely revised 5th edition of the most used introductory text in radio astronomy. It presents a unified treatment of the entire field from centimeter to sub-millimeter wavelengths. Topics covered include instruments, sensitivity considerations, observational methods and interpretations of the data recorded with both single dishes and interferometers. This text is useful to both students and experienced practicing astronomers. Besides making major updates and additions throughout the book, the authors have re-organized a number of chapters to more clearly separate basic theory from rapidly evolving practical aspects. Further, problem sets have been added at the end of each chapter.

  6. Digital Receiver Design for Transmitted Reference Ultra-Wideband Systems

    Directory of Open Access Journals (Sweden)

    Wang Yiyin

    2009-01-01

    Full Text Available Abstract A complete detection, channel estimation, synchronization, and equalization scheme for a transmitted reference (TR ultra-wideband (UWB system is proposed in this paper. The scheme is based on a data model which admits a moderate data rate and takes both the interframe interference (IFI and the intersymbol interference (ISI into consideration. Moreover, the bias caused by the interpulse interference (IPI in one frame is also taken into account. Based on the analysis of the stochastic properties of the received signals, several detectors are studied and evaluated. Furthermore, a data-aided two-stage synchronization strategy is proposed, which obtains sample-level timing in the range of one symbol at the first stage and then pursues symbol-level synchronization by looking for the header at the second stage. Three channel estimators are derived to achieve joint channel and timing estimates for the first stage, namely, the linear minimum mean square error (LMMSE estimator, the least squares (LS estimator, and the matched filter (MF. We check the performance of different combinations of channel estimation and equalization schemes and try to find the best combination, that is, the one providing a good tradeoff between complexity and performance.

  7. Digital Receiver Design for Transmitted Reference Ultra-Wideband Systems

    Directory of Open Access Journals (Sweden)

    Yiyin Wang

    2009-01-01

    Full Text Available A complete detection, channel estimation, synchronization, and equalization scheme for a transmitted reference (TR ultra-wideband (UWB system is proposed in this paper. The scheme is based on a data model which admits a moderate data rate and takes both the interframe interference (IFI and the intersymbol interference (ISI into consideration. Moreover, the bias caused by the interpulse interference (IPI in one frame is also taken into account. Based on the analysis of the stochastic properties of the received signals, several detectors are studied and evaluated. Furthermore, a data-aided two-stage synchronization strategy is proposed, which obtains sample-level timing in the range of one symbol at the first stage and then pursues symbol-level synchronization by looking for the header at the second stage. Three channel estimators are derived to achieve joint channel and timing estimates for the first stage, namely, the linear minimum mean square error (LMMSE estimator, the least squares (LS estimator, and the matched filter (MF. We check the performance of different combinations of channel estimation and equalization schemes and try to find the best combination, that is, the one providing a good tradeoff between complexity and performance.

  8. Ancient Indian Astronomy in Introductory Texts

    Science.gov (United States)

    Narahari Achar, B. N.

    1997-10-01

    It is customary in introductory survey courses in astronomy to devote some time to the history of astronomy. In the available text books only the Greek contribution receives any attention. Apart from Stonehenge and Chichenitza pictures, contributions from Babylon and China are some times mentioned. Hardly any account is given of ancient Indian astronomy. Even when something is mentioned it is incomplete or incorrect or both. Examples are given from several text books currently available. An attempt is made to correct this situation by sketching the contributions from the earliest astronomy of India, namely Vedaanga Jyotisha.

  9. Astronomy stories

    Science.gov (United States)

    Berenson, Rhoda

    2015-03-01

    For many years I have taught physics and astronomy courses to liberal arts students. I have found most of my students to be intelligent and diligent, but not anxious to study science. They typically take the class only because their degree requires a science course. Many arrive having already decided they will not be able to do the math or understand the scientific concepts, and have essentially built a wall between themselves and science. In the 1990s, in an effort to help break down that wall, as part of an NSF-supported course, "The Evolution of the Universe, Earth and Life," I began using creative writing assignments.

  10. Radio astronomy

    CERN Document Server

    Alder, Berni

    1975-01-01

    Methods in Computational Physics, Volume 14: Radio Astronomy is devoted to the role of the digital computer both as a control device and as a calculator in addressing problems related to galactic radio noise. This volume contains four chapters and begins with a technical description of the hardware and the special data-handling problems of using radioheliography, with an emphasis on a selection of observational results obtained with the Culgoora radioheliograph and their significance to solar physics and to astrophysics in general. The subsequent chapter examines interstellar dispersion, i

  11. Global Positioning System (GPS) Receiver Design For Multipaths Mitigation

    National Research Council Canada - National Science Library

    Gadallah, El-Sayed

    1998-01-01

    .... This research introduces a new estimator that can detect the presence of multipath, can determine the unknown number of multipath components and can estimate multipath parameters in the GPS receiver...

  12. Elementary astronomy

    Science.gov (United States)

    Fierro, J.

    2006-08-01

    In developing nations such as Mexico, basic science education has scarcely improved. There are multiple reasons for this problem; they include poor teacher training and curricula that are not challenging for students. I shall suggest ways in which astronomy can be used to improve basic education, it is so attractive that it can be employed to teach how to read and write, learn a second language, mathematics, physics, as well as geography. If third world nations do not teach science in an adequate way, they will be in serious problems when they will try to achieve a better standard of living for their population. I shall also address informal education, it is by this means that most adults learn and keep up to date with subjects that are not their specialty. If we provide good outreach programs in developing nations we can aid adult training; astronomy is ideal since it is particularly multidisciplinary. In particular radio and television programs are useful for popularization since they reach such wide audiences.

  13. Functional design criteria 241-AP-102 Flexible Receiver System

    International Nuclear Information System (INIS)

    Roblyer, S.P.

    1995-01-01

    A mixer pump was installed in the 1.07 m (42-in.) riser of the central pump pit of tank 241-AP-102 to mitigate potential fluid separation particle sedimentation by mixing the tank's contents. The mixer pump performed this function until failure. Its removal is now necessary to meet possible tank content removal commitments or other corrective actions. The proposed removal procedure requires a flexible receiver that will provide a barrier to contamination during removal and transfer of the pump to the mixer pump storage container. This document describes the functional design criteria of the flexible receiver. These criteria include the functional and performance requirements of the flexible receiver as a barrier to contamination during normal conditions and contingencies and the instrumentation requirements

  14. Artificial Intelligence in Astronomy

    Science.gov (United States)

    Devinney, E. J.; Prša, A.; Guinan, E. F.; Degeorge, M.

    2010-12-01

    From the perspective (and bias) as Eclipsing Binary researchers, we give a brief overview of the development of Artificial Intelligence (AI) applications, describe major application areas of AI in astronomy, and illustrate the power of an AI approach in an application developed under the EBAI (Eclipsing Binaries via Artificial Intelligence) project, which employs Artificial Neural Network technology for estimating light curve solution parameters of eclipsing binary systems.

  15. Optimisation of optical receiver for 10 Gbit/s optical duobinary transmission system

    DEFF Research Database (Denmark)

    Zheng, Xueyan; Liu, Fenghai; Jeppesen, Palle

    2001-01-01

    Optimisation of a receiver for an optical duobinary signal is studied numerically. It is shown that a conventional receiver is not optimum neither when a DCF is used before the receiver nor without a DCF being used. The optimum receiver for an optical duobinary system is identified.......Optimisation of a receiver for an optical duobinary signal is studied numerically. It is shown that a conventional receiver is not optimum neither when a DCF is used before the receiver nor without a DCF being used. The optimum receiver for an optical duobinary system is identified....

  16. The physics-astronomy frontier

    International Nuclear Information System (INIS)

    Hoyle, F.; Narlikar, K.

    1980-01-01

    Spacetime diagrams and the structure of matter are considered, and aspects of electrical interaction are investigated. Attention is given to radiation, quantum mechanics, spectrum lines, black bodies, stellar spectra, the H-R diagram, radio astronomy, millimeter-wave astronomy, interstellar grains and infrared astronomy, and X-ray astronomy. The strong and weak interactions are examined, taking into account atoms, nuclei, the evolution of stars, and the measurement of astronomical distances. A description of gravitational interaction is also presented. The laws of motion and gravitation are considered along with black holes, the significance of cosmology, Hubble's law, the expanding universe, the symmetries of the universe, Olbers' paradox, the big-bang universe, Mach's principle, the meaning of the expansion of the system of galaxies, the redshift-magnitude relation of Hubble and Humason, the early universe, and the geometry of special relativity

  17. Pulsar astronomy

    International Nuclear Information System (INIS)

    Lyne, A.G.; Graham-Smith, F.

    1990-01-01

    This account of the properties of pulsars tells an exciting story of discovery in modern astronomy. Pulsars, discovered in 1967, now take their place in a very wide range of astrophysics. They are one of the endpoints of stellar evolution, in which the core of a star collapses to a rapidly spinning neutron star a few kilometres in size. This book is an introductory account for those entering the field. It introduces the circumstances of the discovery and gives an overview of pulsar astrophysics. There are chapters on search techniques, distances, pulse timing, the galactic population of pulsars, binary and millisecond pulsars, geometry and physics of the emission regions, and applications to the interstellar medium. An important feature of this book is the inclusion of an up-to-date catalogue of all known pulsars. (author)

  18. TeachAstronomy.com - Digitizing Astronomy Resources

    Science.gov (United States)

    Hardegree-Ullman, Kevin; Impey, C. D.; Austin, C.; Patikkal, A.; Paul, M.; Ganesan, N.

    2013-06-01

    Teach Astronomy—a new, free online resource—can be used as a teaching tool in non-science major introductory college level astronomy courses, and as a reference guide for casual learners and hobbyists. Digital content available on Teach Astronomy includes: a comprehensive introductory astronomy textbook by Chris Impey, Wikipedia astronomy articles, images from Astronomy Picture of the Day archives and (new) AstroPix database, two to three minute topical video clips by Chris Impey, podcasts from 365 Days of Astronomy archives, and an RSS feed of astronomy news from Science Daily. Teach Astronomy features an original technology called the Wikimap to cluster, display, and navigate site search results. Development of Teach Astronomy was motivated by steep increases in textbook prices, the rapid adoption of digital resources by students and the public, and the modern capabilities of digital technology. This past spring semester Teach Astronomy was used as content supplement to lectures in a massive, open, online course (MOOC) taught by Chris Impey. Usage of Teach Astronomy has been steadily growing since its initial release in August of 2012. The site has users in all corners of the country and is being used as a primary teaching tool in at least four states.

  19. Salt Repository Project transportation system interface requirements: Transportation system/repository receiving facility interface requirements

    International Nuclear Information System (INIS)

    Smith, L.A.; Insalaco, J.W.; Trainer, T.A.

    1988-01-01

    This report is a preliminary review of the interface between the transportation system and the repository receiving facility for a nuclear waste mined geologic disposal system in salt. Criteria for generic cask and facility designs are developed. These criteria are derived by examining the interfaces that occur as a result of the operations needed to receive nuclear waste at a repository. These criteria provide the basis for design of a safe, operable, practical nuclear waste receiving facility. The processing functions required to move the shipping unit from the gate into the unloading area and back to the gate for dispatch are described. Criteria for a generic receiving facility are discussed but no specific facility design is presented or evaluated. The criteria are stated in general terms to allow application to a wide variety of cask and facility designs. 9 refs., 6 figs., 4 tabs

  20. Design of Simplified Maximum-Likelihood Receivers for Multiuser CPM Systems

    Directory of Open Access Journals (Sweden)

    Li Bing

    2014-01-01

    Full Text Available A class of simplified maximum-likelihood receivers designed for continuous phase modulation based multiuser systems is proposed. The presented receiver is built upon a front end employing mismatched filters and a maximum-likelihood detector defined in a low-dimensional signal space. The performance of the proposed receivers is analyzed and compared to some existing receivers. Some schemes are designed to implement the proposed receivers and to reveal the roles of different system parameters. Analysis and numerical results show that the proposed receivers can approach the optimum multiuser receivers with significantly (even exponentially in some cases reduced complexity and marginal performance degradation.

  1. Design of simplified maximum-likelihood receivers for multiuser CPM systems.

    Science.gov (United States)

    Bing, Li; Bai, Baoming

    2014-01-01

    A class of simplified maximum-likelihood receivers designed for continuous phase modulation based multiuser systems is proposed. The presented receiver is built upon a front end employing mismatched filters and a maximum-likelihood detector defined in a low-dimensional signal space. The performance of the proposed receivers is analyzed and compared to some existing receivers. Some schemes are designed to implement the proposed receivers and to reveal the roles of different system parameters. Analysis and numerical results show that the proposed receivers can approach the optimum multiuser receivers with significantly (even exponentially in some cases) reduced complexity and marginal performance degradation.

  2. The Astronomy Workshop

    Science.gov (United States)

    Hamilton, D. P.

    2005-05-01

    The Astronomy Workshop (http://janus.astro.umd.edu) is a collection of interactive online educational tools developed for use by students, educators, and the general public. The more than 20 tools in the Astronomy Workshop are rated for ease-of-use, and have been extensively tested in large university survey courses, classes for undergraduate majors, and High Schools. Here we briefly describe a few of the more popular tools. The Life of the Sun (New!): The history of the Sun is animated as a movie, showing students how the size and color of our star has evolved and will evolve in time. Animated Orbits of Planets and Moons: The orbital motions of planets, moons, asteroids, and comets are animated at their correct relative speeds in accurate to-scale drawings. Solar System Collisions: This most popular of our applications shows what happens when an asteroid or comet with user-defined size and speed impacts a given planet. The program calculates many effects, including the country of impact (if Earth is the target), energy of explosion, crater size, and magnitude of the ``planetquake'' generated. It also displays a relevant image (e.g. terrestrial crater, lunar crater, etc.). Astronomical Distances: Travel away from the Earth at a chosen speed and see how long it takes to reach other planets, stars and galaxies. This tool helps students visualize astronomical distances in an intuitive way. Funding for the Astronomy Workshop is provided by a NASA EPO grant.

  3. Astronomy Research Seminars

    Science.gov (United States)

    Genet, Russell M.

    2018-06-01

    Astronomy Research Seminars are offered by a rapidly growing number of community colleges and universities. Over the past decade some 120 student team research papers have been published with approximately 500 coauthors. Each team manages their own research, obtains and analyzes original data, writes a team paper, obtains an external review, submits their paper for publication, and gives a public PowerPoint presentation. The student teams are supported by: (1) an extensive community-of-practice which consists of professional and amateur astronomers, educators, and Seminar graduates; (2) the Institute for Student Astronomical Research (www.in4star.org); (3) the Small Telescope Astronomy Research Handbook and (4) an in-person/online, open-source Canvas learning management system with videos, quizzes, and other, extensive supporting material. Team research projects are completed in a semester or less and are managed by the students themselves. The Seminars have expanded from double star astronomy to asteroid astrometry, eclipsing binary times of minima, and exoplanet transits. Conducting authentic research inspires students, provides them with important skills in teamwork, project management and scientific literacy, and gives them confidence in their abilities to participate in scientific research. Being coauthors of published papers boosts student educational careers with respect to admissions and scholarships.

  4. Teaching and Learning Astronomy

    Science.gov (United States)

    Pasachoff, Jay; Percy, John

    2009-07-01

    Preface; Part I. Astronomy in the Curriculum Around the World: Preface; 1. Why astronomy is useful and should be included in the school curriculum John R. Percy; 2. Astronomy and mathematics education Rosa M. Ros; 3. Astronomy in the curriculum around the world; 4. Engaging gifted science students through astronomy Robert Hollow; 5. Poster highlights: astronomy in the curriculum around the world; Part II. Astronomy Education Research: Preface; 6. Astronomy education research down under John M. Broadfoot and Ian S. Ginns; 7. A contemporary review of K-16 astronomy education research Janelle M. Bailey and Timothy F. Slater; 8. Implementing astronomy education research Leonarda Fucili; 9. The Astronomy Education Review: report on a new journal Sidney C. Wolff and Andrew Fraknoi; 10. Poster highlights: astronomy education research; Part III. Educating Students: Preface; 11. Textbooks for K-12 astronomy Jay M. Pasachoff; 12. Distance/internet astronomy education David H. McKinnon; 13. Educating students with robotic telescopes - open discussion; 14. Poster highlights - educating students; Part IV. Educating teachers: Preface; 15. Pre-service astronomy education of teachers Mary Kay Hemenway; 16. In-service education of teachers Michèle Gerbaldi; 17. Poster highlights: educating teachers; Part V. Astronomy and Pseudoscience: Preface; 18. Astronomy, pseudoscience and rational thinking Jayant V. Narlikar; 19. Astronomical pseudosciences in North America John R. Percy and Jay M. Pasachoff; Part VI. Astronomy and Culture: Preface; 20. Teaching astronomy in other cultures: archeoastronomy Julieta Fierro; 21. Poster highlights: astronomy and culture; Part VII. Astronomy in Developing Countries: Preface; 22. Astronomy Curriculum for developing countries Case Rijsdijk; 23. Science education resources for the developing countries James C. White II; Part VIII. Public Outreach in Astronomy: Preface; 24. What makes informal education programs successful? Nahide Craig and Isabel

  5. Binocular astronomy

    CERN Document Server

    Tonkin, Stephen

    2014-01-01

    Binoculars have, for many, long been regarded as an “entry level” observational tool, and relatively few have used them as a serious observing instrument. This is changing! Many people appreciate the relative comfort of two-eyed observing, but those who use binoculars come to realize that they offer more than comfort. The view of the stars is more aesthetically pleasing and therefore binocular observers tend to observe more frequently and for longer periods. Binocular Astronomy, 2nd Edition, extends its coverage of small and medium binoculars to large and giant (i.e., up to 300mm aperture) binoculars and also binoviewers, which brings the work into the realm of serious observing instruments. Additionally, it goes far deeper into the varying optical characteristics of binoculars, giving newcomers and advanced astronomers the information needed to make informed choices on purchasing a pair. It also covers relevant aspects of the physiology of binocular (as in “both eyes”) observation. The first edition ...

  6. Astronomy in the City for Astronomy Education

    Science.gov (United States)

    Ros, Rosa M.; Garc, Beatriz

    2016-10-01

    Astronomy is part of our culture. Astronomy cannot be isolated in a classroom, it has to be integrated in the normal life of teachers and students. ``Astronomy in the city'' is an important part of NASE (Network for Astronomy School Education) (Ros & Hemenway 2012). In each NASE course we introduce a ``working group session'' chaired by a local expert in cultural astronomy. The chair introduces several examples of astronomy in their city and after that, the participants have the opportunity to discuss and mention several similar examples. After this session all participants visit one or two sites proposed and introduced by the chair. After more than 5 years using this method we visited and discovered several examples of astronomy in the city: •Astronomy in ancient typical clothes. •Archaeological temples oriented according to the sunrise or set. •Petroglyphs with astronomical meaning. •Astronomy in monuments. •Sundials. •Oriented Colonial churches. •Astronomy in Souvenirs. In any case, teachers and students discover that Astronomy is part of their everyday life. They can take into account the Sun's path when they park their car or when they take a bus ``what is the best part in order to be seat in the shadow during the journey?'' The result is motivation to go with ``open eyes'' when they are in the street and they try to get more and more information about their surroundings. In summary, one of the main activities is to introduce local cultural aspects in NASE astronomy courses. The participants can discover a new approach to local culture from an astronomical point of view.

  7. Innovation in Astronomy Education

    Science.gov (United States)

    Pasachoff, Jay M.; Ros, Rosa M.; Pasachoff, Naomi

    2013-01-01

    Preface; Part I. General Strategies for Effective Teaching: Introduction; 1. Main objectives of SpS2; 2. Learning astronomy by doing astronomy; 3. Hands-on Universe-Europe; 4. Life on Earth in the atmosphere of the Sun; 5. A model of teaching astronomy to pre-service teachers; 6. How to teach, learn about, and enjoy astronomy; 7. Clickers: a new teaching tool of exceptional promise; 8. Educational opportunities in pro-am collaboration; 9. Teaching history of astronomy to second-year engineering students; 10. Teaching the evolution of stellar and Milky Way concepts through the ages; 11. Educational efforts of the International Astronomical Union; 12. Astronomy in culture; 13. Light pollution: a tool for astronomy education; 14. Astronomy by distance learning; 15. Edible astronomy demonstrations; 16. Amateur astronomers as public outreach partners; 17. Does the Sun rotate around Earth or Earth rotate around the Sun?; 18. Using sounds and sonifications for astronomy outreach; 19. Teaching astronomy and the crisis in science education; 20. Astronomy for all as part of a general education; Poster abstracts; Part II. Connecting Astronomy with the Public: Introduction; 21. A status report from the Division XII working group; 22. Outreach using media; 23. Astronomy podcasting; 24. IAU's communication strategy, hands-on science communication, and the communication of the planet definition discussion; 25. Getting a word in edgeways: the survival of discourse in audiovisual astronomy; 26. Critical evaluation of the new Hall of Astronomy; 27. Revitalizing astronomy teaching through research on student understanding; Poster abstracts; Part III. Effective Use of Instruction and Information Technology: Introduction; 28. ESO's astronomy education program; 29. U.S. student astronomy research and remote observing projects; 30. Global network of autonomous observatories dedicated to student research; 31. Remote telescopes in education: report of an Australian study; 32. Visualizing

  8. Digital Receiver Design for Transmitted Reference Ultra-Wideband Systems

    NARCIS (Netherlands)

    Wang, Y.; Leus, G.; Van der Veen, A.J.

    2009-01-01

    A complete detection, channel estimation, synchronization, and equalization scheme for a transmitted reference (TR) ultra-wideband (UWB) system is proposed in this paper. The scheme is based on a data model which admits a moderate data rate and takes both the interframe interference (IFI) and the

  9. The Astronomy Workshop

    Science.gov (United States)

    Hamilton, Douglas P.

    2012-05-01

    {\\bf The Astronomy Workshop} (http://janus.astro.umd.edu) is a collection of interactive online educational tools developed for use by students, educators, professional astronomers, and the general public. The more than 20 tools in the Astronomy workshop are rated for ease-of-use, and have been extensively tested in large university survey courses as well as more specialized classes for undergraduate majors and graduate students. Here we briefly describe a few of the available tools. {\\bf Solar Systems Visualizer}: The orbital motions of planets, moons, and asteroids in the Solar System as well as many of the planets in exoplanetary systems are animated at their correct relative speeds in accurate to-scale drawings. Zoom in from the chaotic outer satellite systems of the giant planets all the way to their innermost ring systems. {\\bf Solar System Calculators}: These tools calculate a user-defined mathematical expression simultaneously for all of the Solar System's planets (Planetary Calculator) or moons (Satellite Calculator). Key physical and orbital data are automatically accessed as needed. {\\bf Stellar Evolution}: The "Life of the Sun" tool animates the history of the Sun as a movie, showing students how the size and color of our star has evolved and will evolve over billions of years. In "Star Race," the user selects two stars of different masses and watches their evolution in a split-screeen format that emphasizes the great differences in stellar lifetimes and fates.

  10. Selected topics on data analysis in astronomy

    International Nuclear Information System (INIS)

    Scarsi, L.

    1987-01-01

    The contents of this book are: General Lectures Given at the Erice II Workshop on Data Analysis in Astronomy: Fundamentals in Data Analysis in Astronomy; Computational Techniques; Evolution of Architectures for Data Processing; Hardware for Graphics and Image Display; and Data Analysis Systems

  11. Advances in astronomy and astrophysics

    CERN Document Server

    Kopal, Zdenek

    1968-01-01

    Advances in Astronomy and Astrophysics, Volume 6 brings together numerous research works on different aspects of astronomy and astrophysics. This volume is composed of five chapters, and starts with the description of improved methods for analyzing and classifying families of periodic orbits in a conservative dynamical system with two degrees of freedom. The next chapter describes the variation of fractional luminosity of distorted components of close binary systems in the course of their revolution, or the accompanying changes in radial velocity. This topic is followed by discussions on vari

  12. Practical astronomy with your calculator

    CERN Document Server

    Duffett-Smith, Peter

    1989-01-01

    Practical Astronomy with your Calculator, first published in 1979, has enjoyed immense success. The author's clear and easy to follow routines enable you to solve a variety of practical and recreational problems in astronomy using a scientific calculator. Mathematical complexity is kept firmly in the background, leaving just the elements necessary for swiftly making calculations. The major topics are: time, coordinate systems, the Sun, the planetary system, binary stars, the Moon, and eclipses. In the third edition there are entirely new sections on generalised coordinate transformations, nutr

  13. Astrology as Cultural Astronomy

    Science.gov (United States)

    Campion, Nicholas

    The practice of astrology can be traced in most if not all human societies, in most time periods. Astrology has prehistoric origins and flourishes in the modern world, where it may be understood as a form of ethnoastronomy - astronomy practiced by the people. The Western tradition, which originated in Mesopotamia and was developed in the Greek world, has been most studied by academics. However, India is also home to a tradition which has survived in a continuous lineage for 2,000 years. Complex systems of astrology also developed in China and Mesoamerica, while all other human societies appear to seek social and religious meaning in the stars.

  14. Astronomy and Politics

    Science.gov (United States)

    Steele, John M.

    The relationship between astronomy and politics is a complex but important part of understanding the practice of astronomy throughout history. This chapter explores some of the ways that astronomy, astrology, and politics have interacted, placing particular focus on the way that astronomy and astrology have been used for political purposes by both people in power and people who wish to influence a ruler's policy. Also discussed are the effects that politics has had on the development of astronomy and, in particular, upon the recording and preservation of astronomical knowledge.

  15. Music and Astronomy Under the Stars 2009

    Science.gov (United States)

    Lubowich, D.

    2010-08-01

    Bring telescopes to where the people are! Music and Astronomy Under the Stars is a three-year NASA-funded astronomy outreach program at community parks during and after music concerts and outdoor family events—such as a Halloween Stars-Spooky Garden Walk. While there have been many astronomy outreach activities and telescope observations at city sidewalks and parks, this program targets a completely different audience: music lovers who are attending summer concerts held in community parks. These music lovers who may never have visited a science museum, planetarium, or star party are exposed to telescope observations and astronomy information with no additional travel costs. Music and Astronomy Under the Stars increased awareness, engagement, and interest in astronomy at classical, pop, rock, and ethnic music concerts. This program includes solar observing before the concerts, telescope observations including a live image projection system, an astronomical video presentation, and astronomy banners/posters. Approximately 500-16,000 people attended each event and 25% to 50% of the people at each event participated in the astronomy program. This program also reached underrepresented and underserved groups (women, minorities, older adults). The target audience (Nassau and Suffolk Counties, New York) is 2,900,000 people, which is larger than combined population of Atlanta, Boston, Denver, Minneapolis, and San Francisco. Although eleven events were planned in 2009, two were canceled due to rain and our largest event, the NY Philharmonic in the Park (attended by 67,000 people in 2008), was cancelled for financial reasons. Our largest event in 2009 was the Tanglewood Music Festival, Lenox MA, attended by 16,000 people where over 5000 people participated in astronomy activities. The Amateur Observers' Society of New York assisted with the NY concerts and the Springfield STARS astronomy club assisted at Tanglewood. In 2009 over 15,000 people participated in astronomy

  16. Advances in astronomy and astrophysics

    CERN Document Server

    Kopal, Zdenek

    1962-01-01

    Advances in Astronomy and Astrophysics, Volume 1 brings together numerous research works on different aspects of astronomy and astrophysics. This book is divided into five chapters and begins with an observational summary of the shock-wave theory of novae. The subsequent chapter provides the properties and problems of T tauri stars and related objects. These topics are followed by discussions on the structure and origin of meteorites and cosmic dust, as well as the models for evaluation of mass distribution in oblate stellar systems. The final chapter describes the methods of polarization mea

  17. Vistas in astronomy. Volume 16

    International Nuclear Information System (INIS)

    Beer, A.

    1974-01-01

    A series of papers dealing with theoretical and experimental work in solar, planetary, and stellar astronomy, including stellar spectroscopy, photometry, and radio astronomy. The topics covered include: solar flares, the historical development of solar theories, the intrinsic light variation and the reflection effect in very close eclipsing binary systems with distorted components, spectroscopic binaries, early-type stars with abnormal spectra, photometric classification of the O-B stars, the nova DQ Herculis, emission nebulas at radio wavelengths, and the planetary nebulas as radio sources. (IAA)

  18. African Cultural Astronomy

    CERN Document Server

    Holbrook, Jarita C; Medupe, R. Thebe; Current Archaeoastronomy and Ethnoastronomy research in Africa

    2008-01-01

    Astronomy is the science of studying the sky using telescopes and light collectors such as photographic plates or CCD detectors. However, people have always studied the sky and continue to study the sky without the aid of instruments this is the realm of cultural astronomy. This is the first scholarly collection of articles focused on the cultural astronomy of Africans. It weaves together astronomy, anthropology, and Africa. The volume includes African myths and legends about the sky, alignments to celestial bodies found at archaeological sites and at places of worship, rock art with celestial imagery, and scientific thinking revealed in local astronomy traditions including ethnomathematics and the creation of calendars. Authors include astronomers Kim Malville, Johnson Urama, and Thebe Medupe; archaeologist Felix Chami, and geographer Michael Bonine, and many new authors. As an emerging subfield of cultural astronomy, African cultural astronomy researchers are focused on training students specifically for do...

  19. Design, demonstration and analysis of a modified wavelength-correlating receiver for incoherent OCDMA system.

    Science.gov (United States)

    Zhou, Heng; Qiu, Kun; Wang, Leyang

    2011-03-28

    A novel wavelength-correlating receiver for incoherent Optical Code Division Multiple Access (OCDMA) system is proposed and demonstrated in this paper. Enabled by the wavelength conversion based scheme, the proposed receiver can support various code types including one-dimensional optical codes and time-spreading/wavelength-hopping two dimensional codes. Also, a synchronous detection scheme with time-to- wavelength based code acquisition is proposed, by which code acquisition time can be substantially reduced. Moreover, a novel data-validation methodology based on all-optical pulse-width monitoring is introduced for the wavelength-correlating receiver. Experimental demonstration of the new proposed receiver is presented and low bit error rate data-receiving is achieved without optical hard limiting and electronic power thresholding. For the first time, a detailed theoretical performance analysis specialized for the wavelength-correlating receiver is presented. Numerical results show that the overall performance of the proposed receiver prevails over conventional OCDMA receivers.

  20. Acceptance test procedure, 241-SY-101 Flexible Receiver System, Phase III testing

    International Nuclear Information System (INIS)

    Ritter, G.A.

    1994-01-01

    This Acceptance Test Procedure is for the 241-SY-101 Flexible Receiver System, Phase III Testing. This procedure will test the sealing integrity of the Flexible Receiver System to ensure that release of waste and aerosols will be minimized during the removal of the test mixer pump from tank SY-101

  1. Acceptance test report for the 241-SY-101 Flexible Receiver Gamma Detector System

    International Nuclear Information System (INIS)

    Dowell, J.L.

    1995-01-01

    This Acceptance Test Report is for the 241-SY-101 Flexible Receiver Gamma Detector System. This test verified that the data logger and data converter for the gamma detector system functions as intended

  2. Encyclopedia of Astronomy and Astrophysics

    CERN Document Server

    2002-01-01

    Interstellar medium, Light, Magnetisphere, Matter, Planet Earth, Public Impact, Solar Activity, Solar Heliosphere, Solar Interior, Solar Systems, Space, Stellar Astrophysics, Stellar Populations, Telescopes, Time The Encyclopedia of Astronomy and Astrophysics covers 30 major subject areas, such as Active galaxies, Astrometry, Astrophysical theory, Atmospheres, Binary stars, Biography, Clusters, Coordinates, Cosmology, Earth, Education, Galaxies,

  3. Astronomy in my shopping cart: Today I bought some asteroids, hundreds of black holes and three Solar Systems!

    Science.gov (United States)

    Boccato, C.; Lazzaretto, E.

    2008-06-01

    Here we will present a pilot project that will be tested and developed throughout 2007/08 in advance of the International Year of Astronomy. Why "putting astronomy in the shopping cart"? The aim of the project is to publicise astrophysics at a popular level, choosing a place that best matches the meaning of the word `popular': the shopping mall. With this project we want to arouse consumer interest in science, making use of the supermarket inside any shopping mall: a place people are familiar with and where they find common consumer goods. The final purpose is to give our science consumer the chance to bring home shopping bags filled not only with consumer goods, but also with a piece of knowledge about astronomy, astrophysics and the way astronomers work and think to understand the Universe and its phenomena.

  4. A freely available real-time operating system well suited for astronomy and the physical sciences

    Science.gov (United States)

    Pedretti, Ettore; Monnier, John D.; Thureau, Nathalie D.; Berger, David H.

    2006-06-01

    This paper wants to be a practical example in building a real-time data-acquisition and control system from scratch using relatively non-expensive PC hardware and open-source software. The practical example of building the control system for the Michigan Infrared Combiner (MIRC) at the CHARA interferometer will be used to give the reader a 'hands-on' experience in installing and configuring the RTAI-Fusion real-time operating system and developing a complete control system with it.

  5. Eumetcast receiving station integration withinthe satellite image database interface (SAIDIN) system.

    OpenAIRE

    Chic, Òscar

    2010-01-01

    Within the tasks devoted to operational oceanography, Coastal Ocean Observatory at Institut de Ciències del Mar (CSIC) has acquired an European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT) Broadcast System for Environmental Data (EUMETCast reception system) to replace a satellite direct broadcast system that receives data via High Resolution Picture Transmission (HRPT). EUMETCast system can receive data based on standard Digital Video Broadcastin...

  6. Engineering satellite-based navigation and timing global navigation satellite systems, signals, and receivers

    CERN Document Server

    Betz, J

    2016-01-01

    This book describes the design and performance analysis of satnav systems, signals, and receivers. It also provides succinct descriptions and comparisons of all the world’s satnav systems. Its comprehensive and logical structure addresses all satnav signals and systems in operation and being developed. Engineering Satellite-Based Navigation and Timing: Global Navigation Satellite Systems, Signals, and Receivers provides the technical foundation for designing and analyzing satnav signals, systems, and receivers. Its contents and structure address all satnav systems and signals: legacy, modernized, and new. It combines qualitative information with detailed techniques and analyses, providing a comprehensive set of insights and engineering tools for this complex multidisciplinary field. Part I describes system and signal engineering including orbital mechanics and constellation design, signal design principles and underlying considerations, link budgets, qua tifying receiver performance in interference, and e...

  7. Development of a tube receiver for a solar-hybrid microturbine system

    OpenAIRE

    Amsbeck, Lars; Buck, Reiner; Heller, Peter; Jedamski, Jens; Uhlig, Ralf

    2008-01-01

    Solar-hybrid microturbine systems with cogeneration offer new possibilities for the generation of electricity and heat or air conditioning. The solar receiver is an important component of such a system. For a prototype system demo project a tube receiver for a 100kWe microturbine system is currently under development. The receiver is designed for air preheating up to 800°C at a pressure of 4.5 barabs. The challenge of the design is to find the right compromise between high efficiency, low pre...

  8. The Astro-Wise system: a federated information accumulator for astronomy

    NARCIS (Netherlands)

    Valentijn, Edwin A.; Verdoes Kleijn, Gijs

    2007-01-01

    The Astro-Wise consortium has designed a new paradigm, ‘Awe‘, and implemented a fully scalable and distributed information system to overcome the huge information avalanche in wide-field astronomical imaging Surveys.

  9. Challenges in Astronomy Education

    Science.gov (United States)

    De Greve, Jean-Pierre

    2010-11-01

    Astronomy is an attractive subject for education. It deals with fascination of the unknown and the unreachable, yet is uses tools, concepts and insights from various fundamental sciences such as mathematics, physics, chemistry, biology. Because of this it can be well used for introducing sciences to young people and to raise their interest in further studies in that direction. It is also an interesting subject for teaching as its different aspects (observation techniques, theory, data sampling and analysis, modelling,?) offer various didactical approaches towards different levels of pupils, students and different backgrounds. And it gives great opportunities to teach and demonstrate the essence of scientific research, through tutorials and projects. In this paper we discuss some of the challenges education in general, and astronomy in particular, faces in the coming decades, given the major geophysical and technological changes that can be deducted from our present knowledge. This defines a general, but very important background in terms of educational needs at various levels, and in geographical distribution of future efforts of the astronomical community. Special emphasis will be given to creative approaches to teaching, to strategies that are successful (such as the use of tutorials with element from computer games), and to initiatives complementary to the regular educational system. The programs developed by the IAU will be briefly highlighted.

  10. X-ray astronomy

    International Nuclear Information System (INIS)

    Culhane, J.L.; Sanford, P.W.

    1981-01-01

    X-ray astronomy has been established as a powerful means of observing matter in its most extreme form. The energy liberated by sources discovered in our Galaxy has confirmed that collapsed stars of great density, and with intense gravitational fields, can be studied by making observations in the X-ray part of the electromagnetic spectrum. The astronomical objects which emit detectable X-rays include our own Sun and extend to quasars at the edge of the Universe. This book describes the history, techniques and results obtained in the first twenty-five years of exploration. Space rockets and satellites are essential for carrying the instruments above the Earth's atmosphere where it becomes possible to view the X-rays from stars and nebulae. The subject is covered in chapters, entitled: the birth of X-ray astronomy; the nature of X-radiation; X-rays from the Sun; solar-flare X-rays; X-rays from beyond the solar system; supernovae and their remnants; X-rays from binary stars; white dwarfs and neutron stars; black holes; X-rays from galaxies and quasars; clusters of galaxies; the observatories of the future. (author)

  11. Performance of Turbo Interference Cancellation Receivers in Space-Time Block Coded DS-CDMA Systems

    Directory of Open Access Journals (Sweden)

    Emmanuel Oluremi Bejide

    2008-07-01

    Full Text Available We investigate the performance of turbo interference cancellation receivers in the space time block coded (STBC direct-sequence code division multiple access (DS-CDMA system. Depending on the concatenation scheme used, we divide these receivers into the partitioned approach (PA and the iterative approach (IA receivers. The performance of both the PA and IA receivers is evaluated in Rayleigh fading channels for the uplink scenario. Numerical results show that the MMSE front-end turbo space-time iterative approach receiver (IA effectively combats the mixture of MAI and intersymbol interference (ISI. To further investigate the possible achievable data rates in the turbo interference cancellation receivers, we introduce the puncturing of the turbo code through the use of rate compatible punctured turbo codes (RCPTCs. Simulation results suggest that combining interference cancellation, turbo decoding, STBC, and RCPTC can significantly improve the achievable data rates for a synchronous DS-CDMA system for the uplink in Rayleigh flat fading channels.

  12. Armenian Archaeoastronomy and Astronomy in Culture

    Science.gov (United States)

    Mickaelian, Areg M.; Farmanyan, Sona V.

    2016-12-01

    A review is given on archaeoastronomy in Armenia and astronomical knowledge reflected in the Armenian culture. Astronomy in Armenia was popular since ancient times and Armenia is rich in its astronomical heritage, such as the names of the constellations, ancient observatories, Armenian rock art (numerous petroglyphs of astronomical content), ancient and medieval Armenian calendars, astronomical terms and names used in Armenian language since II-I millennia B.C., records of astronomical events by ancient Armenians (e.g. Halley's comet in 87 B.C., supernovae explosion in 1054), the astronomical heritage of the Armenian medieval great thinker Anania Shirakatsi's (612-685), medieval sky maps and astronomical devices by Ghukas (Luca) Vanandetsi (XVII-XVIII centuries) and Mkhitar Sebastatsi (1676-1749), etc. For systemization and further regular studies, we have created a webpage devoted to Armenian archaeoastronomical matters at Armenian Astronomical Society (ArAS) website. Issues on astronomy in culture include astronomy in ancient Armenian cultures, ethnoastronomy, astronomy in Armenian religion and mythology, astronomy and astrology, astronomy in folklore and poetry, astronomy in arts, astrolinguistics and astroheraldry. A similar webpage for Astronomy in Armenian Culture is being created at ArAS website and a permanent section "Archaeoastronomy and Astronomy in Culture" has been created in ArAS Electronic Newsletter. Several meetings on this topic have been organized in Armenia during 2007-2014, including the archaeoastronomical meetings in 2012 and 2014, and a number of books have been published. Several institutions are related to these studies coordinated by Byurakan Astrophysical Observatory (BAO) and researchers from the fields of astronomy, history, archaeology, literature, linguistics, etc. are involved.

  13. The purpose of astronomy

    OpenAIRE

    Davoust, Emmanuel

    1995-01-01

    This is a presentation of the purpose of astronomy in the context of modern society. After exposing two misconceptions about astronomy, I detail its role in five domains, certified knowledge, incorporated abilities, innovations, collective goods, and popular science; with each domain is associated an institution, an incentive, and a method of evaluation. Finally, I point out the role of astronomy as a source of inspiration in other fields than science.

  14. Precise Receiver Clock Offset Estimations According to Each Global Navigation Satellite Systems (GNSS) Timescales

    Science.gov (United States)

    Thongtan, Thayathip; Tirawanichakul, Pawit; Satirapod, Chalermchon

    2017-12-01

    Each GNSS constellation operates its own system times; namely, GPS system time (GPST), GLONASS system time (GLONASST), BeiDou system time (BDT) and Galileo system time (GST). They could be traced back to Coordinated Universal Time (UTC) scale and are aligned to GPST. This paper estimates the receiver clock offsets to three timescales: GPST, GLONASST and BDT. The two measurement scenarios use two identical multi-GNSS geodetic receivers connected to the same geodetic antenna through a splitter. One receiver is driven by its internal oscillators and another receiver is connected to the external frequency oscillators, caesium frequency standard, kept as the Thailand standard time scale at the National Institute of Metrology (Thailand) called UTC(NIMT). The three weeks data are observed at 30 seconds sample rate. The receiver clock offsets with respected to the three system time are estimated and analysed through the geodetic technique of static Precise Point Positioning (PPP) using a data processing software developed by Wuhan University - Positioning And Navigation Data Analyst (PANDA) software. The estimated receiver clock offsets are around 32, 33 and 18 nanoseconds from GPST, GLONASST and BDT respectively. This experiment is initially stated that each timescale is inter-operated with GPST and further measurements on receiver internal delay has to be determined for clock comparisons especially the high accuracy clock at timing laboratories.

  15. Space and astronomy

    CERN Document Server

    Kirkland, Kyle

    2010-01-01

    Some daring explorers like to study distant frontiers by venturing out into them, but others prefer to study them by bringing them, or representative samples, a little closer to the lab. Both options are pursued in the fields of space and astronomy. Space exploration and astronomy are intricately linked and are examined in-depth in this guide. Dedicated to the scientists who explore the frontiers of space and astronomy-and the results of their unfamiliar findings-each chapter in Space and Astronomy explores one of the frontiers of this science. The development of technology, such as rocket pro

  16. Discussion of mechanical design for pressured cavity-air-receiver in solar power tower system

    Energy Technology Data Exchange (ETDEWEB)

    Fan, Zhilin; Zhang, Yaoming; Liu, Deyou; Wang, Jun; Liu, Wei [Hohai Univ., Nanjing (China). New Materials and Energy Sources Research and Exploitation Inst.

    2008-07-01

    In 2005, Hohai university and Nanjing Chunhui science and technology Ltd. of China, cooperating with Weizmann Institute of Science and EDIG Ltd. of Israel, built up a 70kWe solar power tower test plant in Nanjing, Jiangsu province, China, which was regarded as the first demonstration project to demonstrate the feasibility of solar power tower system in China. The system consists of heliostats field providing concentrated sunlight, a solar tower with a height of 33 meter, a pressured cavity-air-receiver transforming solar energy to thermal energy, a modified gas turbine adapting to solar power system, natural gas subsystem for solar-hybrid generation, cooling water subsystem for receiver and CPC, controlling subsystem for whole plant, et al. In this system, air acts as actuating medium and the system works in Brayton cycle. Testing results show that solar power tower system is feasible in China. To promote the development of solar powered gas turbine system and the pressured cavity-air-receiver technology in China, it is necessary to study the mechanical design for pressured Cavity-air-receiver. Mechanical design of pressured cavity-air-receiver is underway and some tentative principles for pressured cavity-air-receiver design, involving in power matching, thermal efficiency, material choosing, and equipment security and machining ability, are presented. At the same time, simplified method and process adapted to engineering application for the mechanical design of pressured cavity-air-receiver are discussed too. Furthermore, some design parameters and appearance of a test sample of pressured cavity-air-receiver designed in this way is shown. It is appealed that, in China, the research in this field should be intensified and independent knowledge patents for pivotal technological equipments such as receiver in solar power tower system should be formed. (orig.)

  17. Message-Passing Receivers for Single Carrier Systems with Frequency-Domain Equalization

    DEFF Research Database (Denmark)

    Zhang, Chuanzong; Manchón, Carles Navarro; Wang, Zhongyong

    2015-01-01

    In this letter, we design iterative receiver algorithms for joint frequency-domain equalization and decoding in a single carrier system assuming perfect channel state information. Based on an approximate inference framework that combines belief propagation (BP) and the mean field (MF) approximation......, we propose two receiver algorithms with, respectively, parallel and sequential message-passing schedules in the MF part. A recently proposed receiver based on generalized approximate message passing (GAMP) is used as a benchmarking reference. The simulation results show that the BP-MF receiver...

  18. Radiometric calibration of wide-field camera system with an application in astronomy

    Science.gov (United States)

    Vítek, Stanislav; Nasyrova, Maria; Stehlíková, Veronika

    2017-09-01

    Camera response function (CRF) is widely used for the description of the relationship between scene radiance and image brightness. Most common application of CRF is High Dynamic Range (HDR) reconstruction of the radiance maps of imaged scenes from a set of frames with different exposures. The main goal of this work is to provide an overview of CRF estimation algorithms and compare their outputs with results obtained under laboratory conditions. These algorithms, typically designed for multimedia content, are unfortunately quite useless with astronomical image data, mostly due to their nature (blur, noise, and long exposures). Therefore, we propose an optimization of selected methods to use in an astronomical imaging application. Results are experimentally verified on the wide-field camera system using Digital Single Lens Reflex (DSLR) camera.

  19. Relativistic Astronomy

    Science.gov (United States)

    Zhang, Bing; Li, Kunyang

    2018-02-01

    The “Breakthrough Starshot” aims at sending near-speed-of-light cameras to nearby stellar systems in the future. Due to the relativistic effects, a transrelativistic camera naturally serves as a spectrograph, a lens, and a wide-field camera. We demonstrate this through a simulation of the optical-band image of the nearby galaxy M51 in the rest frame of the transrelativistic camera. We suggest that observing celestial objects using a transrelativistic camera may allow one to study the astronomical objects in a special way, and to perform unique tests on the principles of special relativity. We outline several examples that suggest transrelativistic cameras may make important contributions to astrophysics and suggest that the Breakthrough Starshot cameras may be launched in any direction to serve as a unique astronomical observatory.

  20. Visual lunar and planetary astronomy

    CERN Document Server

    Abel, Paul G

    2013-01-01

    With the advent of CCDs and webcams, the focus of amateur astronomy has to some extent shifted from science to art. The object of many amateur astronomers is now to produce “stunning images” that, although beautiful, are not intended to have scientific merit. Paul Abel has been addressing this issue by promoting visual astronomy wherever possible – at talks to astronomical societies, in articles for popular science magazines, and on BBC TV’s The Sky at Night.   Visual Lunar and Planetary Astronomy is a comprehensive modern treatment of visual lunar and planetary astronomy, showing that even in the age of space telescopes and interplanetary probes it is still possible to contribute scientifically with no more than a moderately priced commercially made astronomical telescope.   It is believed that imaging and photography is somehow more objective and more accurate than the eye, and this has led to a peculiar “crisis of faith” in the human visual system and its amazing processing power. But by anal...

  1. Military/Civilian Mixed-Mode Global Positioning System (GPS) Receiver (MMGR)

    National Research Council Canada - National Science Library

    Peczalski, Andy; Kriz, Jeff; Carlson, Stephen G; Sampson, Steven J

    2004-01-01

    ... AND T) MMGR objective of meeting pervasive defense system requirements and civilian needs for ultra-small GPS receiver technology is dependent in part upon the creation of multi- L-band reconfigurable...

  2. Thermal Analysis of the Receiver of a Standalone Pilot Solar Dish–Stirling System

    Directory of Open Access Journals (Sweden)

    Ehsan Gholamalizadeh

    2018-06-01

    Full Text Available Recent developments in solar thermal systems have aroused considerable interest in several countries with high solar potential. One of the most promising solar driven technologies is the solar thermal dish-Stirling system. One of the main issues of the solar dish–Stirling system is thermal losses from its components. The majority of the thermal losses of the system occur through its receiver before the thermal energy is converted to electrical energy by the Stirling engine. The goal of this investigation is to analyze the thermal performance of the receiver of a standalone pilot solar dish–Stirling system installed in Kerman City, Iran, to be used in remote off-grid areas of the Kerman Province. An analytical model was developed to predict the input energy, thermal losses, and thermal efficiency of the receiver. The receiver thermal model was first validated by comparing simulation results to experimental measurements for the EuroDish project. Then, the incident flux intensity intercepted by the receiver aperture, the thermal losses through the receiver (including conduction, convection, and radiation losses, and the power output during daytime hours (average day of each month for a year were predicted. The results showed that the conduction loss was small, while the convection and radiation losses played major roles in the total thermal losses through the receiver. The convection loss is dominant during the early morning and later evening hours, while radiation loss reaches its highest value near midday. Finally, the thermal efficiency of the receiver and the power output for each working hour throughout the year were calculated. The maximum performance of the system occurred at midday in the middle of July, with a predicted power output of 850 W, and a receiver efficiency of about 60%. At this time, a conduction loss of about 266 W, a convection loss of 284 W, and a radiation loss of about 2000 W were estimated.

  3. Advances in astronomy and astrophysics 9

    CERN Document Server

    Kopal, Zdenek

    1972-01-01

    Advances in Astronomy and Astrophysics, Volume 9 covers reviews on the advances in astronomy and astrophysics. The book presents reviews on the Roche model and its applications to close binary systems. The text then describes the part played by lunar eclipses in the evolution of astronomy; the classical theory of lunar eclipses; deviations from geometrical theory; and the methods of photometric observations of eclipses. The problems of other phenomena related in one way or another to lunar eclipses are also considered. The book further tackles the infrared observation on the eclipsed moon, as

  4. WorldWide Telescope: A Newly Open Source Astronomy Visualization System

    Science.gov (United States)

    Fay, Jonathan; Roberts, Douglas A.

    2016-01-01

    After eight years of development by Microsoft Research, WorldWide Telescope (WWT) was made an open source project at the end of June 2015. WWT was motivated by the desire to put new surveys of objects, such as the Sloan Digital Sky Survey in the context of the night sky. The development of WWT under Microsoft started with the creation of a Windows desktop client that is widely used in various education, outreach and research projects. Using this, users can explore the data built into WWT as well as data that is loaded in. Beyond exploration, WWT can be used to create tours that present various datasets a narrative format.In the past two years, the team developed a collection of web controls, including an HTML5 web client, which contains much of the functionality of the Windows desktop client. The project under Microsoft has deep connections with several user communities such as education through the WWT Ambassadors program, http://wwtambassadors.org/ and with planetariums and museums such as the Adler Planetarium. WWT can also support research, including using WWT to visualize the Bones of the Milky Way and rich connections between WWT and the Astrophysical Data Systems (ADS, http://labs.adsabs.harvard.edu/adsabs/). One important new research connection is the use of WWT to create dynamic and potentially interactive supplements to journal articles, which have been created in 2015.Now WWT is an open source community lead project. The source code is available in GitHub (https://github.com/WorldWideTelescope). There is significant developer documentation on the website (http://worldwidetelescope.org/Developers/) and an extensive developer workshops (http://wwtworkshops.org/?tribe_events=wwt-developer-workshop) has taken place in the fall of 2015.Now that WWT is open source anyone who has the interest in the project can be a contributor. As important as helping out with coding, the project needs people interested in documentation, testing, training and other roles.

  5. Reduced Complexity Detection in MIMO Systems with SC-FDE Modulations and Iterative DFE Receivers

    Directory of Open Access Journals (Sweden)

    Filipe Casal Ribeiro

    2018-04-01

    Full Text Available This paper considers a Multiple-Input Multiple-Output (MIMO system with P transmitting and R receiving antennas and different overall noise characteristics on the different receiver antennas (e.g., due to nonlinear effects at the receiver side. Each communication link employs a Single-Carrier with Frequency-Domain Equalization (SC-FDE modulation scheme, and the receiver is based on robust iterative frequency-domain multi-user detectors based on the Iterative Block Decision Feedback Equalization (IB-DFE concept. We present low complexity efficient receivers that can employ low resolution Analog-to-Digital Converters (ADCs and require the inversion of matrices with reduced dimension when the number of receive antennas is larger than the number of independent data streams. The advantages of the proposed techniques are particularly high for highly unbalanced MIMO systems, such as in the uplink of Base Station (BS cooperation systems that aim for Single-Frequency Network (SFN operation or massive MIMO systems with much more antennas at the receiver side.

  6. Astronomy for beginners

    CERN Document Server

    Becan, Jeff

    2008-01-01

    Astronomy For Beginners is a friendly and accessible guide to our universe, our galaxy, our solar system and the planet we call home. Each year as we cruise through space on this tiny blue-green wonder, a number of amazing and remarkable events occur. For example, like clockwork, we'll run head-on into asteroid and cometary debris that spreads shooting stars across our skies. On occasion, we'll get to watch the disk of the Moon passing the Sun, casting its shadow on the face of the Earth, and sometimes we'll get to watch our own shadow as it glides across the face of the Moon. The Sun's path w

  7. NMR transmit-receive system with short recovery time and effective isolation

    Science.gov (United States)

    Jurga, K.; Reynhardt, E. C.; Jurga, S.

    A transmit-receive system with a short recovery time and excellent isolation has been developed. The system operates in conjunction with an ENI Model 3200L broadband amplifier and a spin-lock NMR pulse spectrometer. The system has been tested in the frequency range 5.5 to 52 MHz and seems not to generate any background noise.

  8. Implementation of a vector-based tracking loop receiver in a pseudolite navigation system.

    Science.gov (United States)

    So, Hyoungmin; Lee, Taikjin; Jeon, Sanghoon; Kim, Chongwon; Kee, Changdon; Kim, Taehee; Lee, Sanguk

    2010-01-01

    We propose a vector tracking loop (VTL) algorithm for an asynchronous pseudolite navigation system. It was implemented in a software receiver and experiments in an indoor navigation system were conducted. Test results show that the VTL successfully tracks signals against the near-far problem, one of the major limitations in pseudolite navigation systems, and could improve positioning availability by extending pseudolite navigation coverage.

  9. Study on radiation flux of the receiver with a parabolic solar concentrator system

    International Nuclear Information System (INIS)

    Mao, Qianjun; Shuai, Yong; Yuan, Yuan

    2014-01-01

    Highlights: • The idea of integral dish and multi-dishes in a parabolic solar collector has been proposed. • The impacts of three factors of the receiver have been investigated. • The radiation flux distribution can benefit from a large system error. - Abstract: The solar receiver plays a key role in the performance of a solar dish electric generator. Its radiation flux distribution can directly affect the efficiency of the parabolic solar concentrator system. In this paper, radiation flux distribution of the receiver is simulated successfully using MCRT method. The impacts of incident solar irradiation, aspect ratio (the ratio of the receiver height to the receiver diameter), and system error on the radiation flux of the receiver are investigated. The parameters are studied in the following ranges: incident solar irradiation from 100 to 1100 W/m 2 , receiver aspect ratio from 0.5 to 1.5, and the system error from 0 to 10 mrad. A non-dimensional parameter Θ is defined to represent the ratio of radiation flux to incident solar irradiation. The results show that the maximum of Θ is about 200 in simulation conditions. The aspect ratio and system error have a significant impact on the radiation flux. The optimal receiver aspect ratio is 1.5 at a constant incident solar irradiation, and the maximum of radiation flux increases with decreasing system error, however, the radiation flux distribution can benefit from a large system error. Meanwhile, effects of integral dish and multi-dishes on the radiation flux distribution have been investigated. The results show that the accuracy of two cases can be ignored within the same parameters

  10. Interdisciplinary Astronomy Activities

    Science.gov (United States)

    Nerantzis, Nikolaos; Mitrouda, Aikaterini; Reizopoulou, Ioanna; Sidiropoulou, Eirini; Hatzidimitriou, Antonios

    2016-04-01

    On November 9th, 2015, three didactical hours were dedicated to Interdisciplinary Astronomy Activities (http://wp.me/p6Hte2-1I). Our students and their teachers formed three groups and in rotation, were engaged with the following activities: (a) viewing unique images of the Cosmos in the mobile planetarium STARLAB (http://www.planitario.gr/tholos-starlab-classic-standard.html), (b) watching the following videos: Journey to the end of the universe (https://youtu.be/Ufl_Nwbl8xs), Rosetta update (https://youtu.be/nQ9ivd7wv30), The Solar System (https://youtu.be/d66dsagrTa0), Ambition the film (https://youtu.be/H08tGjXNHO4) in the school's library. Students and teachers were informed about our solar system, the Rosetta mission, the universe, etc. and (c) tactile activities such as Meet our home and Meet our neighbors (http://astroedu.iau.org, http://nuclio.org/astroneighbours/resources) and the creation of planets' 3D models (Geology-Geography A' Class Student's book, pg.15). With the activities above we had the pleasure to join the Cosmic Light Edu Kit / International Year of Light 2015 program. After our Interdisciplinary Astronomy Activities, we did a "small" research: our students had to fill an evaluation about their educational gains and the results can be found here http://wp.me/p6Hte2-2q. Moreover, we discussed about Big Ideas of Science (http://wp.me/p3oRiZ-dm) and through the "big" impact of the Rosetta mission & the infinity of our universe, we print posters with relevant topics and place them to the classrooms. We thank Rosa Doran (Nuclio - President of the Executive Council) for her continuous assistance and support on innovative science teaching proposals. She is an inspiration.

  11. Indian Astronomy: History of

    Science.gov (United States)

    Mercier, R.; Murdin, P.

    2002-01-01

    From the time of A macronryabhat under dota (ca AD 500) there appeared in India a series of Sanskrit treatises on astronomy. Written always in verse, and normally accompanied by prose commentaries, these served to create an Indian tradition of mathematical astronomy which continued into the 18th century. There are as well texts from earlier centuries, grouped under the name Jyotishaveda macronn d...

  12. Astronomy in Mozambique

    Science.gov (United States)

    Ribeiro, Valério A. R. M.; Paulo, Cláudio M.

    2015-03-01

    We present the state of Astronomy in Mozambique and how it has evolved since 2009 following the International Year of Astronomy. Activities have been lead by staff at University Eduardo Mondlane and several outreach activities have also flourished. In 2010 the University introduced its first astronomy module, Introduction to Astronomy and Astrophysics, for the second year students in the Department of Physics. The course has now produced the first students who will be graduating in late 2012 with some astronomy content. Some of these students will now be looking for further studies and those who have been keen in astronomy have been recommended to pursue this as a career. At the university level we have also discussed on the possibility to introduce a whole astronomy course by 2016 which falls well within the HCD that the university is now investing in. With the announcement that the SKA will be split between South Africa with its partner countries (including Mozambique), and Australia we have been working closely with the Ministry of Science and Technology to make astronomy a priority on its agenda. In this respect, an old telecommunications antenna is being converted by the South Africa SKA Project Office, and donated to Mozambique for educational purposes. It will be situated in Maluana, Mozambique.

  13. Extragalactic infrared astronomy

    International Nuclear Information System (INIS)

    Gondhalekar, P.M.

    1985-05-01

    The paper concerns the field of Extragalactic Infrared Astronomy, discussed at the Fourth RAL Workshop on Astronomy and Astrophysics. Fifteen papers were presented on infrared emission from extragalactic objects. Both ground-(and aircraft-) based and IRAS infrared data were reviewed. The topics covered star formation in galaxies, active galactic nuclei and cosmology. (U.K.)

  14. Optical timing receiver for the NASA laser ranging system. Part I. Constant-fraction discriminator

    International Nuclear Information System (INIS)

    Leskovar, B.; Lo, C.C.

    1975-01-01

    Position-resolution capabilities of the NASA laser ranging system are essentially determined by time-resolution capabilities of its optical timing receiver. The optical timing receiver consists of a fast photoelectric device, primarily a standard of microchannel-plate-type photomultiplier or an avalanche photodiode detector, a timing discriminator, a high-precision time-interval digitizer, and a signal-processing system. The time-resolution capabilities of the receiver are determined by the photoelectron time spread of the photoelectric device, the time walk and resolution characteristics of the timing discriminator, and the time-interval digitizer. It is thus necessary to evaluate available fast photoelectronic devices with respect to their time-resolution capabilities, and to design a very low time walk timing discriminator and a high-precision time digitizer which will be used in the laser ranging system receiver. (auth)

  15. Highlights of Astronomy, Vol. 16

    Science.gov (United States)

    Montmerle, Thierry

    2015-04-01

    Part I. Invited Discourses: 1. The Herschel view of star formation; 2. Past, present and future of Chinese astronomy; 3. The zoo of galaxies; 4. Supernovae, the accelerating cosmos, and dark energy; Part II. Joint Discussion: 5. Very massive stars in the local universe; 6. 3-D views of the cycling Sun in stellar context; 7. Ultraviolet emission in early-type galaxies; 8. From meteors and meteorites to their parent bodies: current status and future developments; 9. The connection between radio properties and high-energy emission in AGNs; 10. Space-time reference systems for future research; Part III. Special Sessions: 11. Origin and complexity of massive star clusters; 12. Cosmic evolution of groups and clusters of galaxies; 13. Galaxy evolution through secular processes; 14. New era for studying interstellar and intergalactic magnetic fields; 15. The IR view of massive stars: the main sequence and beyond; 16. Science with large solar telescopes; 17. The impact hazard: current activities and future plans; 18. Calibration of star-formation rate measurements across the electromagnetic spectrum; 19. Future large scale facilities; 20. Dynamics of the star-planet relations strategic plan and the Global Office of Astronomy for Development; 21. Strategic plan and the Global Office of Astronomy for Development; 22. Modern views of the interstellar medium; 23. High-precision tests of stellar physics from high-precision photometry; 24. Communicating astronomy with the public for scientists; 25. Data intensive astronomy; 26. Unexplained spectral phenomena in the interstellar medium; 27. Light pollution: protecting astronomical sites and increasing global awareness through education.

  16. A digital receiver module with direct data acquisition for magnetic resonance imaging systems.

    Science.gov (United States)

    Tang, Weinan; Sun, Hongyu; Wang, Weimin

    2012-10-01

    A digital receiver module for magnetic resonance imaging (MRI) with detailed hardware implementations is presented. The module is based on a direct sampling scheme using the latest mixed-signal circuit design techniques. A single field-programmable gate array chip is employed to perform software-based digital down conversion for radio frequency signals. The modular architecture of the receiver allows multiple acquisition channels to be implemented on a highly integrated printed circuit board. To maintain the phase coherence of the receiver and the exciter in the context of direct sampling, an effective phase synchronization method was proposed to achieve a phase deviation as small as 0.09°. The performance of the described receiver module was verified in the experiments for both low- and high-field (0.5 T and 1.5 T) MRI scanners and was compared to a modern commercial MRI receiver system.

  17. 2009 International Year of Astronomy (IYA2009)

    Science.gov (United States)

    Wiseman, Jennifer

    2009-01-01

    400 years ago, Galileo first turned a telescope to the sky, and to honor that historic moment, 2009 has been designated the International Year of Astronomy (IYA2009). This session will feature two scientists who have used the telescope to understand our solar system and well beyond to yield fantastic new discoveries. Jennifer Wiseman will share the work she does with NASA, presenting beautiful and tantalizing images from the Hubble Space Telescope and discussing how space astronomy can inspire all ages.

  18. Message-Passing Receiver for OFDM Systems over Highly Delay-Dispersive Channels

    DEFF Research Database (Denmark)

    Barbu, Oana-Elena; Manchón, Carles Navarro; Rom, Christian

    2017-01-01

    Propagation channels with maximum excess delay exceeding the duration of the cyclic prefix (CP) in OFDM systems cause intercarrier and intersymbol interference which, unless accounted for, degrade the receiver performance. Using tools from Bayesian inference and sparse signal reconstruction, we...... derive an iterative algorithm that estimates an approximate representation of the channel impulse response and the noise variance, estimates and cancels the intrinsic interference and decodes the data over a block of symbols. Simulation results show that the receiver employing our algorithm outperforms...

  19. Solar receiver heliostat reflector having a linear drive and position information system

    Science.gov (United States)

    Horton, Richard H.

    1980-01-01

    A heliostat for a solar receiver system comprises an improved drive and control system for the heliostat reflector assembly. The heliostat reflector assembly is controllably driven in a predetermined way by a light-weight drive system so as to be angularly adjustable in both elevation and azimuth to track the sun and efficiently continuously reflect the sun's rays to a focal zone, i.e., heat receiver, which forms part of a solar energy utilization system, such as a solar energy fueled electrical power generation system. The improved drive system includes linear stepping motors which comprise low weight, low cost, electronic pulse driven components. One embodiment comprises linear stepping motors controlled by a programmed, electronic microprocessor. Another embodiment comprises a tape driven system controlled by a position control magnetic tape.

  20. The Radio JOVE Project - Shoestring Radio Astronomy

    Science.gov (United States)

    Thieman, J.; Flagg, R.; Greenman, W.; Higgins, C.; Reyes, F.; Sky, J.

    2010-01-01

    Radio JOVE is an education and outreach project intended to give students and other interested individuals hands-on experience in learning radio astronomy. They can do this through building a radio telescope from a relatively inexpensive kit that includes the parts for a receiver and an antenna as well as software for a computer chart recorder emulator (Radio Skypipe) and other reference materials

  1. The Future of Space Astronomy.

    Science.gov (United States)

    Field, George B.

    1984-01-01

    Discusses various aspects of space astronomy, considering advantages, the space telescope and ground-based astronomy, an orbiting astrophysics facility, solar physics, and other areas. Indicates that earth-based astronomy will continue to be carried out there and space astronomy will be limited to observations that can be carried out only from…

  2. Teaching Astronomy with Technology

    Science.gov (United States)

    Austin, Carmen; Impey, Chris David; Wenger, Matthew

    2015-01-01

    Students today are expected to have access to computers and the Internet. Students young and old, in school and out of school, are interested in learning about astronomy, and have computers to use for this. Teach Astronomy is a website with a comprehensive digital astronomy textbook freely available to students and educators. In addition to the textbook, there are astronomy Wikipedia articles, image archives from Astronomy Picture of the Day and AstroPix, and video lectures covering all topics of astronomy. Teach Astronomy has a unique search tool called the wikimap that can be used to search through all of the resources on the site. Astronomy: State of the Art (ASOTA) is a massive, open, online course (MOOC). Over 18,000 students have enrolled over the past year and half. This MOOC has been presented in various forms. First, only to students on the web, with content released weekly on host site Udemy. Then to university students who met formally in the classroom for educational activities, but were also expected to watch lectures online on their own time. Presently, it is available online for students to go at their own pace. In the future it will be available in an extended format on a new host site, Coursera. ASOTA instructors use social media to interact with students. Students ask questions via the course host site, Udemy. Live question and answer sessions are conducted using Google Hangouts on Air, and interesting and relevant astronomy news, or supplementary educational content is shared via the ASOTA Facebook page. Teaching on the Internet may seem impersonal and impractical, but by learning to use all of these tools, instructors have the ability to interact with students, and keep them engaged.

  3. Making Space for Specialized Astronomy Resources

    Science.gov (United States)

    MacMillan, D.

    2007-10-01

    With the growth of both free and subscription-based resources, articles on astronomy have never been easier to find. Locating the best and most current materials for any given search, however, now requires multiple tools and strategies dependent on the query. An analysis of the tools currently available shows that while astronomy is well-served by Google Scholar, Scopus and Inspec, its literature is best accessed through specialized resources such as ADS (Astrophysics Data System). While no surprise to astronomers, this has major implications for those of us who teach information literacy skills to astronomy students and work in academic settings where astronomy is just one of many subjects for which our non-specialist colleagues at the reference desk provide assistance. This paper will examine some of the implications of this analysis for library instruction, reference assistance and training, and library webpage development.

  4. Direct Heat-Flux Measurement System (MDF) for Solar central Receiver Evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Ballestrin, J.

    2001-07-01

    A direct flux measurement system, MDF, has been designed, constructed and mounted on top of the SSPS-CRS tower at the Plataforma Solar de Almeria (PSA) in addition to an indirect flux measurement system based on a CCD camera. It's one of the main future objectives to compare systematically both measurements of the concentrated solar power, increasing in this way the confidence in the estimate of this quantity. Today everything is prepared to perform the direct flux measurement on the aperture of solar receivers: calorimeter array, data acquisition system and software. the geometry of the receiver determines the operation and analysis procedures to obtain the indecent power onto the defined area. The study of previous experiences with direct flux measurement systems ha been useful to define a new simpler and more accurate system. A description of each component of the MDF system is included, focusing on the heat-flux sensors or calorimeters, which enables these measurements to be done in a few seconds without water-cooling. The incident solar power and the spatial flux distribution on the aperture of the volumetric receiver Hitrec II are supplied by the above-mentioned MDF system. The first results obtained during the evaluation of this solar receiver are presented including a sunrise-sunset test. All these measurements have been concentrated in one coefficient that describes the global behavior of the Solar Power Plant. (Author) 18 refs.

  5. Europe's Astronomy Teachers Meet at ESO

    Science.gov (United States)

    1994-12-01

    European Association for Astronomy Education Formed A joint EU/ESO Workshop (1) on the Teaching of Astronomy in Europe was held at the ESO Headquarters from November 25-30, 1994, under the auspices of the 1994 European Week for Scientific Culture. More than 100 teachers from secondary schools in 17 European countries participated together with representatives of national ministries and local authorities, as well as professional astronomers. This meeting was the first of its kind ever held and was very successful. As a most visible and immediate outcome, the participants agreed to form the "European Association for Astronomy Education (EAAE)", uniting astronomy educators all over Europe into one network. A provisional Executive Committee of the EAAE was elected which will work towards the organisation of a constitutional conference within the next year. The participants unanimously adopted a "Declaration on the Teaching of Astronomy in Europe", specifying the overall aims and initial actions needed to achieve them. Astronomy: Science, Technology and Culture At the beginning of the Workshop the participants listened to lectures by several specialists about some of the most active fields of astronomy. The scientific sessions included topics as diverse as minor bodies in the solar system, nucleosynthesis, interstellar chemistry and cosmology. Then followed overviews of various recent advances in astronomical technology, some of which are already having direct impact on highly specialized sectors of European industry. They included the advanced use of computers in astronomy, for instance within image processing and data archiving, as well as a demonstration of remote observing. Discussing the cultural aspects, Nigel Calder (UK) and Hubert Reeves (France) emphasized the important role of astronomy in modern society, in particular its continuing influence on our perceptions of mankind's unique location in time and space. Teaching of Astronomy in European Countries

  6. Astronomy and culture

    CERN Document Server

    Hetherington, Edith

    2009-01-01

    While astronomy is a burgeoning science, with tremendous increases in knowledge every year, it also has a tremendous past, one that has altered humanity's understanding of our place in the universe. The impact of astronomy on culture - whether through myths and stories, or through challenges to the intellectual status quo - is incalculable. This volume in the Greenwood Guides to the Universe series examines how human cultures, in all regions and time periods, have tried to make sense of the wonders of the universe. Astronomy and Culture shows students how people throughout time have struggled

  7. Discovering Astronomy Through Poetry

    Science.gov (United States)

    Mannone, John C.

    2011-05-01

    The literature is replete with astronomical references. And much of that literature is poetry. Using this fact, not only can the teacher infuse a new appreciation of astronomy, but also, the student has the opportunity to rediscover history through astronomy. Poetry can be an effective icebreaker in the introduction of new topics in physics and astronomy, as well as a point of conclusion to a lecture. This presentation will give examples of these things from the ancient literature (sacred Hebraic texts), classical literature (Homer's Iliad and Odyssey), traditional poetry (Longfellow, Tennyson and Poe) and modern literature (Frost, Kooser, and others, including the contemporary work of this author).

  8. Development of an integrated heat pipe-thermal storage system for a solar receiver

    Science.gov (United States)

    Keddy, E. S.; Sena, J. T.; Merrigan, M. A.; Heidenreich, G.; Johnson, S.

    1987-07-01

    The Organic Rankine Cycle (ORC) Solar Dynamic Power System (SDPS) is one of the candidates for Space Station prime power application. In the low Earth orbit of the Space Station approximately 34 minutes of the 94-minute orbital period is spent in eclipse with no solar energy input to the power system. For this period the SDPS will use thermal energy storage (TES) material to provide a constant power output. An integrated heat-pipe thermal storage receiver system is being developed as part of the ORC-SDPS solar receiver. This system incorporates potassium heat pipe elements to absorb and transfer the solar energy within the receiver cavity. The heat pipes contain the TES canisters within the potassium vapor space with the toluene heater tube used as the condenser region of the heat pipe. During the insolation period of the Earth orbit, solar energy is delivered to the heat pipe in the ORC-SDPS receiver cavity. The heat pipe transforms the non-uniform solar flux incident in the heat pipe surface within the receiver cavity to an essentially uniform flux at the potassium vapor condensation interface in the heat pipe. During solar insolation, part of the thermal energy is delivered to the heater tube and the balance is stored in the TES units. During the eclipse period of the orbit, the balance stored in the TES units is transferred by the potassium vapor to the toluene heater tube.

  9. Development of an integrated heat pipe-thermal storage system for a solar receiver

    Science.gov (United States)

    Keddy, E. S.; Sena, J. T.; Merrigan, M. A.; Heidenreich, G.; Johnson, S.

    1987-01-01

    The Organic Rankine Cycle (ORC) Solar Dynamic Power System (SDPS) is one of the candidates for Space Station prime power application. In the low Earth orbit of the Space Station approximately 34 minutes of the 94-minute orbital period is spent in eclipse with no solar energy input to the power system. For this period the SDPS will use thermal energy storage (TES) material to provide a constant power output. An integrated heat-pipe thermal storage receiver system is being developed as part of the ORC-SDPS solar receiver. This system incorporates potassium heat pipe elements to absorb and transfer the solar energy within the receiver cavity. The heat pipes contain the TES canisters within the potassium vapor space with the toluene heater tube used as the condenser region of the heat pipe. During the insolation period of the Earth orbit, solar energy is delivered to the heat pipe in the ORC-SDPS receiver cavity. The heat pipe transforms the non-uniform solar flux incident in the heat pipe surface within the receiver cavity to an essentially uniform flux at the potassium vapor condensation interface in the heat pipe. During solar insolation, part of the thermal energy is delivered to the heater tube and the balance is stored in the TES units. During the eclipse period of the orbit, the balance stored in the TES units is transferred by the potassium vapor to the toluene heater tube.

  10. Neural Network-Based Receiver in Band-Limited Communication System with MPPSK Modulation

    Directory of Open Access Journals (Sweden)

    Wang Zixin

    2018-01-01

    Full Text Available As a type of the spectrally efficient modulation, the m-ary phase position shift keying (MPPSK has been considered to meet the increasing spectrum requirement in the future wireless system. To limit the signal bandwidth and cancel the out-band interference the band-pass filters are used, which introduce the waveform distortion and inter-symbol interference (ISI. Therefore, a single hidden-layer neural network (NN-based receiver is proposed to jointly equalize and demodulate the received signal. The impulse response of the system is static and the network parameters can be obtained after off-line training. The number of the hidden nodes is also determined through simulations. Simulation results show that the NN-based receiver works well in the communication system with different allocated bandwidths. By observing the modified confusion matrix, the false symbol decision is relevant to modulation index, waveform distortions and the ISI.

  11. A novel mirror diversity receiver for indoor MIMO visible light communication systems

    KAUST Repository

    Park, Kihong

    2016-12-24

    In this paper, we propose and study a non-imaging receiver design reducing the correlation of channel matrix for indoor multiple-input multiple-output (MIMO) visible light communication (VLC) systems. Contrary to previous works, our proposed mirror diversity receiver (MDR) not only blocks the reception of light on one specific direction but also improves the channel gain on the other direction by receiving the light reflected by a mirror deployed between the photodetectors. We analyze the channel capacity and optimal height of mirror in terms of maximum channel capacity for a 2 × 2 MIMO-VLC system in a 2-dimensional geometric model. We prove that this constructive and destructive effects in channel matrix resulting from our proposed MDR are more beneficial to obtain well-conditioned channel matrix which is suitable for implementing spatial-multiplexing MIMO-VLC systems in order to support high data rate.

  12. Examining relationships between receiving mental health services in the Pennsylvania prison system and time served.

    Science.gov (United States)

    Metraux, Stephen

    2008-07-01

    This study examined a cohort of 7,046 men who were released from the Pennsylvania State prison system between 1999 and 2002 to Philadelphia County to assess the relationships between receipt of mental health services in prison and prison exit. Administrative data on prison stays for 7,046 men released from Pennsylvania prisons to Philadelphia locations were analyzed. Of the 7,046 men, 8.7% received ongoing or intensive mental health services and 25.9% received mental health services while incarcerated. Multivariate analyses indicate that use of mental health services was positively associated with increased odds of serving the full prison sentence (as opposed to receiving parole), although the relationship between mental health services received and length of prison episode was inconclusive. Dynamics related to prison release warrant further attention in efforts to reduce the prevalence of mental illness in prisons and to facilitate community reentry for persons so diagnosed.

  13. Thermal modeling of a pressurized air cavity receiver for solar dish Stirling system

    Science.gov (United States)

    Zou, Chongzhe; Zhang, Yanping; Falcoz, Quentin; Neveu, Pierre; Li, Jianlan; Zhang, Cheng

    2017-06-01

    A solar cavity receiver model for the dish collector system is designed in response to growing demand of renewable energy. In the present research field, no investigations into the geometric parameters of a cavity receiver have been performed. The cylindrical receiver in this study is composed of an enclosed bottom at the back, an aperture at the front, a helical pipe inside the cavity and an insulation layer on the external surface of the cavity. The influence of several critical receiver parameters on the thermal efficiency is analyzed in this paper: cavity inner diameter and cavity length. The thermal model in this paper is solved considering the cavity dimensions as variables. Implementing the model into EES, each parameter influence is separately investigated, and a preliminary optimization method is proposed.

  14. The Astronomy of Africa’s Health Systems Literature During the MDG Era: Where Are the Systems Clusters?

    Science.gov (United States)

    Sheff, Mallory; Boyer, Christopher B

    2015-01-01

    Growing international concern about the need for improved health systems in Africa has catalyzed an expansion of the health systems literature. This review applies a bibliometric procedure to analyze the acceleration of scientific writing on this theme. We focus on research published during the Millennium Development Goal (MDG) era between 1990 and 2014, reporting findings from a systematic review of a database comprised of 17,655 articles about health systems themes from sub-Saharan African countries or subregions. Using bibliometric tools for co-word textual analysis, we analyzed the incidence and associations of keywords and phrases to generate and visualize topical foci on health systems as clusters of themes, much in the manner that astronomers represent groupings of stars as galaxies of celestial entities. The association of keywords defines their relative position, with the size of images weighted by the relative frequency of terms. Sets of associated keywords are arrayed as stars that cluster as “galaxies” of concepts in the knowledge universe represented by health systems research from sub-Saharan Africa. Results show that health systems research is dominated by literature on diseases and categorical systems research topics, rather than on systems science that cuts across diseases or specific systemic themes. Systems research is highly developed in South Africa but relatively uncommon elsewhere in the region. “Black holes” are identified by searching for terms in our keyword library related to terms in widely cited reviews of health systems. Results identify several themes that are unexpectedly uncommon in the country-specific health systems literature. This includes research on the processes of achieving systems change, the health impact of systems strengthening, processes that explain the systems determinants of health outcomes, or systematic study of organizational dysfunction and ways to improve system performance. Research quantifying the

  15. Astronomy in Everyday Life

    Science.gov (United States)

    Rosenberg, M.; Bladon, G.; Russo, P.; Christensen, L. L.

    2014-01-01

    For a long time astronomers and other scientists believed that the importance of their work was evident to society. But in these difficult days of financial austerity, even the most obvious benefits of science have to undergo careful scrutiny. So, now more than ever is the time to highlight the importance of astronomy as a field in terms of its contributions to our technology, our mind sets and our lives. Here we will outline both the tangible and intangible reasons why astronomy is an important part of society. Whilst considerable attention will be given to technology and knowledge transfer from astronomy, perhaps the most important contribution outlined is the awareness that astronomy gives us of the vastness of the Universe and our place within it.

  16. Gravity wave astronomy

    International Nuclear Information System (INIS)

    Pinheiro, R.

    1979-01-01

    The properties and production of gravitational radiation are described. The prospects for their detection are considered including the Weber apparatus and gravity-wave telescopes. Possibilities of gravity-wave astronomy are noted

  17. 2004 ASTRONOMY & ASTROPHYSICS

    Indian Academy of Sciences (India)

    user

    This publication of the Academy on Astronomy and Astrophysics is unique in ... bring out position papers on societal issues where science plays a major ..... funding agencies, the Astronomical Society of ..... orbit very close to the parent star.

  18. Galactic radio astronomy

    CERN Document Server

    Sofue, Yoshiaki

    2017-01-01

    This book is a concise primer on galactic radio astronomy for undergraduate and graduate students, and provides wide coverage of galactic astronomy and astrophysics such as the physics of interstellar matter and the dynamics and structure of the Milky Way Galaxy and galaxies. Radio astronomy and its technological development have led to significant progress in galactic astronomy and contributed to understanding interstellar matter and galactic structures. The book begins with the fundamental physics of radio-wave radiation, i.e., black body radiation, thermal emission, synchrotron radiation, and HI and molecular line emissions. The author then gives overviews of ingredients of galactic physics, including interstellar matter such as the neutral (HI), molecular hydrogen, and ionized gases, as well as magnetic fields in galaxies. In addition, more advanced topics relevant to the Galaxy and galaxies are also contained here: star formation, supernova remnants, the Galactic Center and black holes, galactic dynamics...

  19. Stamping through astronomy

    CERN Document Server

    Dicati, Renato

    2013-01-01

    Stamps and other postal documents are an attractive vehicle for presenting astronomy and its development. Written with expertise and great enthusiasm, this unique book offers a historical and philatelic survey of astronomy and some related topics on space exploration. It contains more than 1300 color reproductions of stamps relating to the history of astronomy, ranging from the earliest observations of the sky to modern research conducted with satellites and space probes. Featured are the astronomers and astrophysicists who contributed to this marvelous story – not only Ptolemy, Copernicus, Kepler, Newton, Herschel, and Einstein but also hundreds of other minor protagonists who played an important role in the development of this, the most ancient yet the most modern of all the sciences. The book also examines in depth the diverse areas which have contributed to the history of astronomy, including the instrumentation, the theories, and the observations. Many stamps illustrate the beauty and the mystery of ce...

  20. Astronomy, Astrology, and Medicine

    Science.gov (United States)

    Greenbaum, Dorian Gieseler

    Astronomy and astrology were combined with medicine for thousands of years. Beginning in Mesopotamia in the second millennium BCE and continuing into the eighteenth century, medical practitioners used astronomy/astrology as an important part of diagnosis and prescription. Throughout this time frame, scientists cited the similarities between medicine and astrology, in addition to combining the two in practice. Hippocrates and Galen based medical theories on the relationship between heavenly bodies and human bodies. In an enduring cultural phenomenon, parts of the body as well as diseases were linked to zodiac signs and planets. In Renaissance universities, astronomy and astrology were studied by students of medicine. History records a long tradition of astrologer-physicians. This chapter covers the topic of astronomy, astrology, and medicine from the Old Babylonian period to the Enlightenment.

  1. Combined cycle solar central receiver hybrid power system study. Final technical report. Volume II

    Energy Technology Data Exchange (ETDEWEB)

    None

    1979-11-01

    This study develops the conceptual design for a commercial-scale (nominal 100 MWe) central receiver solar/fossil fuel hybrid power system with combined cycle energy conversion. A near-term, metallic heat pipe receiver and an advanced ceramic tube receiver hybrid system are defined through parametric and market potential analyses. Comparative evaluations of the cost of power generation, the fuel displacement potential, and the technological readiness of these two systems indicate that the near-term hybrid system has better potential for commercialization by 1990. Based on the assessment of the conceptual design, major cost and performance improvements are projected for the near-term system. Constraints preventing wide-spread use were not identified. Energy storage is not required for this system and analyses show no economic advantages with energy storage provisions. It is concluded that the solar hybrid system is a cost effective alternative to conventional gas turbines and combined cycle generating plants, and has potential for intermediate-load market penetration at 15% annual fuel escalation rate. Due to their flexibility, simple solar/nonsolar interfacing, and short startup cycles, these hybrid plants have significant operating advantages. Utility company comments suggest that hybrid power systems will precede stand-alone solar plants.

  2. Multiple Access Interference Reduction Using Received Response Code Sequence for DS-CDMA UWB System

    Science.gov (United States)

    Toh, Keat Beng; Tachikawa, Shin'ichi

    This paper proposes a combination of novel Received Response (RR) sequence at the transmitter and a Matched Filter-RAKE (MF-RAKE) combining scheme receiver system for the Direct Sequence-Code Division Multiple Access Ultra Wideband (DS-CDMA UWB) multipath channel model. This paper also demonstrates the effectiveness of the RR sequence in Multiple Access Interference (MAI) reduction for the DS-CDMA UWB system. It suggests that by using conventional binary code sequence such as the M sequence or the Gold sequence, there is a possibility of generating extra MAI in the UWB system. Therefore, it is quite difficult to collect the energy efficiently although the RAKE reception method is applied at the receiver. The main purpose of the proposed system is to overcome the performance degradation for UWB transmission due to the occurrence of MAI during multiple accessing in the DS-CDMA UWB system. The proposed system improves the system performance by improving the RAKE reception performance using the RR sequence which can reduce the MAI effect significantly. Simulation results verify that significant improvement can be obtained by the proposed system in the UWB multipath channel models.

  3. Astronomy in Second Life

    Directory of Open Access Journals (Sweden)

    Gauthier, A.

    2007-10-01

    Full Text Available Second Life (SL is a multi-user virtual environment that is not limited to adult social entertainment. SL is also a 3D playground for innovative instructors and education/outreach professionals in the sciences. Astronomy and space science have a presence in SL, but it could be so much more. This paper describes some of the current astronomy themed spaces in SL and briefly discusses future innovations.

  4. Optimal Analytical Solution for a Capacitive Wireless Power Transfer System with One Transmitter and Two Receivers

    Directory of Open Access Journals (Sweden)

    Ben Minnaert

    2017-09-01

    Full Text Available Wireless power transfer from one transmitter to multiple receivers through inductive coupling is slowly entering the market. However, for certain applications, capacitive wireless power transfer (CWPT using electric coupling might be preferable. In this work, we determine closed-form expressions for a CWPT system with one transmitter and two receivers. We determine the optimal solution for two design requirements: (i maximum power transfer, and (ii maximum system efficiency. We derive the optimal loads and provide the analytical expressions for the efficiency and power. We show that the optimal load conductances for the maximum power configuration are always larger than for the maximum efficiency configuration. Furthermore, it is demonstrated that if the receivers are coupled, this can be compensated for by introducing susceptances that have the same value for both configurations. Finally, we numerically verify our results. We illustrate the similarities to the inductive wireless power transfer (IWPT solution and find that the same, but dual, expressions apply.

  5. EVALUATION OF CONCEPTUAL FRAMEWORKS IN ASTRONOMY

    Directory of Open Access Journals (Sweden)

    David Pundak

    2016-02-01

    Full Text Available Even though astronomy is the oldest science, it is still an open question how to evaluate students’ understanding in astronomy. In spite of the fact that some methods and evaluation tools have been developed for that purpose, the sources of students' difficulties in astronomy are still unclear. This paper presents an investigation of the changes in conceptual frameworks in astronomy among 50 engineering students as a result of learning a general course in astronomy. A special tool called Conceptual Frameworks in Astronomy (CFA, which was initially used in 1989, was adopted to gather data for the present research. In its new version, the tool includes 23 questions and five to six optional answers to each question. Each of the answers characterizes one of the four conceptual frameworks: pre-scientific, geocentric, heliocentric and sidereal. These four conceptual frameworks act as a taxonomical system that enables us to evaluate astronomical understanding. The paper describes the background of the CFA, its development, and discusses its validity and reliability. Using the CFA we were able to: (1 identify the students’ conceptual frameworks at the beginning of the course and at its end, (2 to evaluate the students’ paradigmatic change following the course. It was found that the measure of the students’ improvement (gain index was g = 0.37. Approximately 45% of the students in the course improved their conceptual frameworks in astronomy and 26% deepened their understanding of the heliocentric or sidereal conceptual frameworks. The CFA can also be applied as an evaluation tool in all schools and institutions that teach astronomy.

  6. Bad Astronomy Goes Hollywood

    Science.gov (United States)

    Plait, P.

    2003-05-01

    It can be argued that astronomy is the oldest of all the sciences, so you'd think that after all this time people would have a pretty good understanding of it. In reality, however, misconceptions about astronomy abound, and even basic concepts are misunderstood. There are many sources of these cosmic misconceptions, including incorrect textbooks, parents and/or teachers who don't understand astronomy and therefore spread misinformation, urban legends, and so on. Perhaps the most pervasive source of bad astronomy is Hollywood. Science fiction movies are enormously popular, but are commonly written and directed by people who don't have even a passing familiarity with astronomy. The smash hit "Armageddon" (the number one box office movie of 1998), for example, used vast quantities of incorrect astronomy in the plot. It reinforced such popular misconceptions as huge asteroids impacting the Earth with little warning, small meteorites being hot when they impact, air existing in space, and that a simple bomb can blow up an asteroid the size of a small moon (even when the bomb is buried only 800 feet deep!). However, movie scenes can be used as a hook that engages the student, helping them learn and remember the correct science. In this talk, I will light-heartedly discuss specific examples of common misinformation, using movie clips, diagrams, and a splash of common sense to show just where Hollywood gets it wrong, and what you can do to help students and the public get it right.

  7. Performance and Complexity Evaluation of Iterative Receiver for Coded MIMO-OFDM Systems

    Directory of Open Access Journals (Sweden)

    Rida El Chall

    2016-01-01

    Full Text Available Multiple-input multiple-output (MIMO technology in combination with channel coding technique is a promising solution for reliable high data rate transmission in future wireless communication systems. However, these technologies pose significant challenges for the design of an iterative receiver. In this paper, an efficient receiver combining soft-input soft-output (SISO detection based on low-complexity K-Best (LC-K-Best decoder with various forward error correction codes, namely, LTE turbo decoder and LDPC decoder, is investigated. We first investigate the convergence behaviors of the iterative MIMO receivers to determine the required inner and outer iterations. Consequently, the performance of LC-K-Best based receiver is evaluated in various LTE channel environments and compared with other MIMO detection schemes. Moreover, the computational complexity of the iterative receiver with different channel coding techniques is evaluated and compared with different modulation orders and coding rates. Simulation results show that LC-K-Best based receiver achieves satisfactory performance-complexity trade-offs.

  8. Anterior cruciate ligament reconstruction in a patient who has received systemic steroids for autoimmune disease

    Directory of Open Access Journals (Sweden)

    Tetsuro Ushio

    2018-01-01

    Conclusion: The patient who had received systemic steroids for a long time recovered satisfactorily after the operation, with achievement of knee stability and possibility to prevent degenerative change in the knee joint. ACL reconstruction should be considered even in patients with such medication.

  9. Meteorological applications of a surface network of Global Positioning System receivers

    NARCIS (Netherlands)

    Haan, de S.

    2008-01-01

    This thesis presents meteorological applications of water vapour observations from a surface network of Global Positioning System (GPS) receivers. GPS signals are delayed by the atmo¬sphere due to atmospheric refraction and bending. Mapped to the zenith, this delay is called Zenith Total Delay

  10. Simulation of a ring resonator-based optical beamformer system for phased array receive antennas

    NARCIS (Netherlands)

    Tijmes, M.R.; Meijerink, Arjan; Roeloffzen, C.G.H.; Bentum, Marinus Jan

    2009-01-01

    A new simulator tool is described that can be used in the field of RF photonics. It has been developed on the basis of a broadband, continuously tunable optical beamformer system for phased array receive antennas. The application that is considered in this paper is airborne satellite reception of

  11. Evaluation of Flammable Gas Monitoring and Ventilation System Alternatives for Double-Contained Receiver Tanks

    International Nuclear Information System (INIS)

    GUSTAVSON, R.D.

    1999-01-01

    This study identifies possible flammable gas monitoring and ventilation system alternatives to ensure adequate removal of flammable gases from the Double-Contained Receiver Tank (DCRT) primary tanks during temporary storage of small amounts of waste. The study evaluates and compares these alternatives to support closure of the Flammable Gas Unreviewed Safety Question (USQ TF-96-04330)

  12. System-Level Design of an Integrated Receiver Front End for a Wireless Ultrasound Probe

    DEFF Research Database (Denmark)

    di Ianni, Tommaso; Hemmsen, Martin Christian; Llimos Muntal, Pere

    2016-01-01

    In this paper, a system-level design is presented for an integrated receive circuit for a wireless ultrasound probe, which includes analog front ends and beamformation modules. This paper focuses on the investigation of the effects of architectural design choices on the image quality. The point...

  13. Developing an Astronomy Program at the Crownpoint Institute of Technology

    Science.gov (United States)

    Gino, M. C.

    2004-12-01

    The Crownpoint Institute of Technology (CIT) is a tribal college located on the eastern edge of the Navajo Nation in northwestern New Mexico. Historically CIT is a technical college which grants AAS degrees and certificates in a number of vocational and technical fields. CIT is in the process of seeking higher learning articulation and accreditation, and has received "Candidacy Status" from the North Central Association of Colleges and Schools Commission on Institutions of Higher Education. To meet the demands placed upon the college as it steps into its role as an institution of higher learning, CIT is dedicated to broadening its curriculum with programs that encourage math, science and technology, and to increasing the number of courses that advance knowledge in both Navajo and Western society by enhancing both laboratory and educational technologies. The introduction of astronomy into the science curriculum advances CIT's goals in all of these areas, and presents a unique opportunity to incorporate traditional Navajo scientific knowledge into a technically advanced science program. In this poster we outline the development of the astronomy program, which has started with the inclusion of the first astronomy course into the science curriculum and the acquisition of two small telescope systems for K-14 student use and public outreach, and will continue through the construction of a campus observatory capable of supporting an undergraduate research program. It is our expectation that through the introduction of astronomy into the curriculum, CIT will advance its goals of increasing science and technology educational opportunities for its students and training the next generation of Navajo science and technology professionals, while maintaining an awareness of the needs of the Navajo Nation and a sensitivity to Navajo cultural values and protocols.

  14. Teaching Astronomy with Podcasts of the APOD

    Science.gov (United States)

    Wagner, Robert M.

    2017-01-01

    The APOD website provides many excellent astronomy photos that are used to enhance introductory astronomy classes. For nearly six years, podcasts have been used to enhance learning in introductory astronomy classes at Harrisburg Area Community College. Daily 3-5 minute podcasts have been created and made available through iTunes to students in these classes at no charge. Students are asked to subscribe to the podcast collections and are quizzed on the images discussed throughout the semester. Because the images often focus on current findings in astronomy, the students are given instruction on findings that will not appear in their textbooks for several years. The students also receive a taste of some topics that may not be covered or that are just touched upon because of time limits in the classes. The podcasts have been used successfully with both traditional and fully online classes. The use of the podcasts enhances mobile learning as students can download and listen to the podcasts on their smartphones or tablets at their convenience. The student response to the podcasts has been excellent with some students noting that they continue to follow the website and podcasts even after they have completed the class. With mobile learning expanding, this is an excellent way to reach students and encourage them to further research the various topics in astronomy that are covered in the APOD images.

  15. Optimization of an Angle-Aided Mirror Diversity Receiver for Indoor MIMO-VLC Systems

    KAUST Repository

    Park, Kihong

    2017-02-07

    In this paper, we investigate the channel correlation problem which affects the performance of indoor multiple-input multiple-output (MIMO) visible light communication (VLC) systems. More specifically, in order to reduce the high correlation of channel matrix in MIMO-VLC intensity channel, we propose a non-imaging receiver called angle-aided mirror diversity receiver (AMDR) which utilizes not only a mirror placement but also a variation of orientation angle for the photodetector (PD) plane. Deploying a mirror helps reducing the correlation by blocking the reception of the light in one specific direction and by receiving additional light reflected in the mirror in another direction, while orienting the angle of PD plane into specific direction enables the directional reception of light. Applying a zero-forcing decorrelator at the receiver, we analyze the bit error rate (BER) performance for a 2×2 multiplexing MIMO-VLC system using a 2-dimensional geometric model. In particular, we formulate a min-max BER problem and find the optimal height of mirror and elevation angle of PD plane. Some selected numerical results validate our proposed optimal solution to our min-max BER problem and show that the BER performance of our proposed AMDR outperforms that of the previous non-imaging receivers.

  16. Research on high-temperature heat receiver in concentrated solar radiation system

    Directory of Open Access Journals (Sweden)

    Estera Przenzak

    2017-01-01

    Full Text Available The article presents the results of experimental and computer simulations studies of the high temperature heat receiver working in the concentrated solar radiation system. In order to study the radiation absorption process and heat exchange, the two types of computer simulations were carried out. The first one was used to find the best location for absorber in the concentrating installation. Ray Tracing Monte Carlo (RTMC method in Trace Pro software was used to perform the optical simulations. The results of these simulations were presented in the form of the solar radiation distribution map and chart. The data obtained in RTMC simulations were used as a second type boundary conditions for Computational Fluid Dynamics (CFD simulations. These studies were used to optimize the internal geometry of the receiver and also to select the most effective flow parameters of the working medium. In order to validate the computer simulations, high temperature heat receiver was tested in experimental conditions. The article presents the results of experimental measurements in the form of temperature, radiation intensity and power graphs. The tests were performed for varied flow rate and receiver location. The experimental and computer simulation studies presented in this article allowed to optimize the configuration of concentrating and heat receiving system.

  17. Optimization of an Angle-Aided Mirror Diversity Receiver for Indoor MIMO-VLC Systems

    KAUST Repository

    Park, Kihong; Alouini, Mohamed-Slim

    2017-01-01

    In this paper, we investigate the channel correlation problem which affects the performance of indoor multiple-input multiple-output (MIMO) visible light communication (VLC) systems. More specifically, in order to reduce the high correlation of channel matrix in MIMO-VLC intensity channel, we propose a non-imaging receiver called angle-aided mirror diversity receiver (AMDR) which utilizes not only a mirror placement but also a variation of orientation angle for the photodetector (PD) plane. Deploying a mirror helps reducing the correlation by blocking the reception of the light in one specific direction and by receiving additional light reflected in the mirror in another direction, while orienting the angle of PD plane into specific direction enables the directional reception of light. Applying a zero-forcing decorrelator at the receiver, we analyze the bit error rate (BER) performance for a 2×2 multiplexing MIMO-VLC system using a 2-dimensional geometric model. In particular, we formulate a min-max BER problem and find the optimal height of mirror and elevation angle of PD plane. Some selected numerical results validate our proposed optimal solution to our min-max BER problem and show that the BER performance of our proposed AMDR outperforms that of the previous non-imaging receivers.

  18. Waste receiving and processing facility module 1 data management system software project management plan

    International Nuclear Information System (INIS)

    Clark, R.E.

    1994-01-01

    This document provides the software development plan for the Waste Receiving and Processing (WRAP) Module 1 Data Management System (DMS). The DMS is one of the plant computer systems for the new WRAP 1 facility (Project W-026). The DMS will collect, store, and report data required to certify the low level waste (LLW) and transuranic (TRU) waste items processed at WRAP 1 as acceptable for shipment, storage, or disposal

  19. Waste Receiving and Processing Facility Module 1 Data Management System software requirements specification

    International Nuclear Information System (INIS)

    Rosnick, C.K.

    1996-01-01

    This document provides the software requirements for Waste Receiving and Processing (WRAP) Module 1 Data Management System (DMS). The DMS is one of the plant computer systems for the new WRAP 1 facility (Project W-0126). The DMS will collect, store and report data required to certify the low level waste (LLW) and transuranic (TRU) waste items processed at WRAP 1 as acceptable for shipment, storage, or disposal

  20. Waste Receiving and Processing Facility Module 1 Data Management System Software Requirements Specification

    International Nuclear Information System (INIS)

    Brann, E.C. II.

    1994-01-01

    This document provides the software requirements for Waste Receiving and Processing (WRAP) Module 1 Data Management System (DMS). The DMS is one of the plant computer systems for the new WRAP 1 facility (Project W-026). The DMS will collect, store and report data required to certify the low level waste (LLW) and transuranic (TRU) waste items processed at WRAP 1 as acceptable for shipment, storage, or disposal

  1. Waste Receiving and Processing Facility Module 1 Data Management System Software Requirements Specification

    Energy Technology Data Exchange (ETDEWEB)

    Brann, E.C. II

    1994-09-09

    This document provides the software requirements for Waste Receiving and Processing (WRAP) Module 1 Data Management System (DMS). The DMS is one of the plant computer systems for the new WRAP 1 facility (Project W-026). The DMS will collect, store and report data required to certify the low level waste (LLW) and transuranic (TRU) waste items processed at WRAP 1 as acceptable for shipment, storage, or disposal.

  2. Cultural Astronomy in Armenia and in the World

    Science.gov (United States)

    Farmanyan, S. V.; Mickaelian, A. M.

    2016-12-01

    Cultural Astronomy is the reflection of sky events in various fields of nations' culture. In foreign literature, this field is also called "Astronomy in Culture" or "Astronomy and Culture". Cultural astronomy is the set of interdisciplinary fields studying the astronomical systems of current or ancient societies and cultures. It is manifested in Religion, Mythology, Folklore, Poetry, Art, Linguistics and other fields. In recent years, considerable attention has been paid to this sphere, particularly international organizations were established, conferences are held and journals are published. Armenia is also rich in cultural astronomy. The present paper focuses on Armenian archaeoastronomy and cultural astronomy, including many creations related to astronomical knowledge; calendars, rock art, mythology, etc. On the other hand, this subject is rather poorly developed in Armenia; there are only individual studies on various related issues (especially many studies related to Anania Shirakatsi) but not coordinated actions to manage this important field of investigation.

  3. Development of a platform-independent receiver control system for SISIFOS

    Science.gov (United States)

    Lemke, Roland; Olberg, Michael

    1998-05-01

    Up to now receiver control software was a time consuming development usually written by receiver engineers who had mainly the hardware in mind. We are presenting a low-cost and very flexible system which uses a minimal interface to the real hardware, and which makes it easy to adapt to new receivers. Our system uses Tcl/Tk as a graphical user interface (GUI), SpecTcl as a GUI builder, Pgplot as plotting software, a simple query language (SQL) database for information storage and retrieval, Ethernet socket to socket communication and SCPI as a command control language. The complete system is in principal platform independent but for cost saving reasons we are using it actually on a PC486 running Linux 2.0.30, which is a copylefted Unix. The only hardware dependent part are the digital input/output boards, analog to digital and digital to analog convertors. In the case of the Linux PC we are using a device driver development kit to integrate the boards fully into the kernel of the operating system, which indeed makes them look like an ordinary device. The advantage of this system is firstly the low price and secondly the clear separation between the different software components which are available for many operating systems. If it is not possible, due to CPU performance limitations, to run all the software in a single machine,the SQL-database or the graphical user interface could be installed on separate computers.

  4. Development of Account Receivable and Payable System for Travel Bureau Company

    Science.gov (United States)

    Karma, I. G. M.; Susanti, J.

    2018-01-01

    Sales and purchases of products on credit made by travel bureau companies require serious handling because it involves a lot of money and many parties. This research aims to build information systems to handle account payables and receivables related to the purchase and sale of tour packages on credit. The methodology is object-oriented approach, by using MS. Visual Basic. Net as a programming language and MySQL as its database package. As the results are the Account Receivable information system that is used to handle accounts receivable on agents who have purchased a tour package on credit for the guests it sends, and the Account Payable information system that is used to handle company’s account payable to suppliers who provided products or services to guests who purchase tour packages. Both of these systems handle the interrelated matter of a particular guest. Therefore, if both systems are integrated with the reservation system will be able to provide income statement on the reservation of certain guests.

  5. The history of astronomy a very short introduction

    CERN Document Server

    Hoskin, Michael

    2003-01-01

    The History of Astronomy: A Very Short Introduction traces the history of Western astronomy, from prehistoric times to the origins of astrophysics in the mid-nineteenth century and the technical developments since the Second World War. Astronomy, perhaps the first of the sciences, was already well developed by the time of Christ — the arithmetical astronomy of the Babylonians was merged with the Greek geometrical approach. This legacy was transmitted to the West via Islam and led to the Copernican revolution, which in turn led to Kepler and Newton, who provided the principles on which the exploration of the solar system and the stars continued in the eighteenth- and nineteenth centuries.

  6. Three-phase receiving coil of wireless power transmission system for gastrointestinal robot

    Science.gov (United States)

    Jia, Z. W.; Jiang, T.; Liu, Y.

    2017-11-01

    Power shortage is the bottleneck for the wide application of gastrointestinal (GI) robot. Owing to the limited volume and free change of orientation of the receiving set in GI trace, the optimal of receiving set is the key point to promote the transmission efficiency of wireless power transmission system. A new type of receiving set, similar to the winding of three-phase asynchronous motor, is presented and compared with the original three-dimensional orthogonal coil. Considering the given volume and the space utilization ratio, the three-phase and the three-orthogonal ones are the parameters which are optimized and compared. Both the transmission efficiency and stability are analyzed and verified by in vitro experiments. Animal experiments show that the new one could provide at least 420 mW power in volume of Φ11 × 13mm with a uniformity of 78.3% for the GI robot.

  7. A flexible receiver with fiber optical parametric amplifier in OCDMA-FSO communication system

    Science.gov (United States)

    Xia, Min; Yuan, Jin-hui; Sang, Xin-zhu; Yin, Xiao-li; Rao, Lan; Yu, Chong-xiu

    2014-11-01

    A new receiver is proposed, which uses the fiber optical parametric amplifier (FOPA) in optical code division multiple access (OCDMA) over free space optic (FSO) communication system. The noise tolerance as the performance index in this receiver is derived. The receiver can not only improve the noise tolerance but also change the pump data conveniently for adapting to the length variation of the coding sequence under a complex and fast-changing weather condition. The influence of different factors on the noise tolerance is analyzed, and a significant improvement of about 18.77 dB for the noise tolerance can be achieved when the pump power and the length of coding sequence are 5 W and 256, respectively.

  8. A Pedestrian Dead Reckoning System Integrating Low-Cost MEMS Inertial Sensors and GPS Receiver

    Directory of Open Access Journals (Sweden)

    Jin-feng Li

    2014-04-01

    Full Text Available The body-mounted inertial systems for pedestrian navigation do not require any preinstalled facilities and can run autonomously. The advantages over other technologies make it especially attractive for the applications such as first responders, military and consumer markets. The hardware platform integrating the low-cost, low-power and small-size MEMS (micro-electro-mechanical systems inertial sensors and GPS (global positioning system receiver is proposed. When the satellite signals are available, the location of the pedestrian is directly obtained from the GPS receiver. The inertial sensors are the complement of the GPS receiver in places where the GPS signals are not available, such as indoors, urban canyons and places under dense foliages. The height tracking is achieved by the barometer. The proposed PDR (pedestrian dead reckoning algorithm is real-timely implemented in the platform. The simple but effective step detection and step length estimation method are realized to reduce the computation and memory requirements on the microprocessor. A complementary filter is proposed to fuse the data from the accelerometer, gyroscope and digital compass for decreasing the heading error, which is the main error source in positioning. The reliability and accuracy of the proposed system is verified by field pedestrian walking tests in outdoors and indoors. The positioning error is less than 4% of the total traveled distance. The results indicate that the pedestrian dead reckoning system is able to provide satisfactory tracking performance.

  9. Astronomy from the chair - the application of the Internet in promoting of Astronomy

    Science.gov (United States)

    Tomic, Zoran

    2014-05-01

    Internet and modern communication technologies are an indispensable part of modern life. The use of the Internet makes it possible to enhance the education and expand opportunities for acquiring new knowledge. One example is Astronomy, where today thanks to the Internet, we can control telescopes that are distant from us and listen to lectures from Universities in other countries. "Astronomy from the chair" is the name for a concept where amateur astronomers can deal with astronomy from their homes using the Internet. The concept can be divided into four sections depending on the content being offered: Robotic Observatory, Virtual Observatory, Online astronomy broadcasting and Online courses. Robotic observatory is defined as an astronomical instrument and detection system that enables efficient observation without the need of a person's physical intervention. Virtual Observatory is defined as a collection of databases and software tools that use the Internet as a platform for scientific research. Online astronomy broadcasting is part of concept "Astronomy from the chair" which gives users the opportunity to get directly involved in astronomical observation organized by an amateur astronomer from somewhere in the world. Online courses are groups of sites and organizations that provide the opportunity to amateur astronomers to attend lectures, save and watch video materials from lectures, do homework, communicate with other seminar participants and in that way become familiar with the various areas of Astronomy. This paper discusses a new concept that describes how the Internet can be applied in modern education. In this paper will be described projects that allows a large number of astronomy lovers to do their own research without the need to own a large and expensive set of astronomical equipment (Virtual Telescope from Italy, Observatory "Night Hawk" from Serbia and project "Astronomy from an armchair" at Faculty of Sciences and Mathematics in Nis), to help

  10. Gnuastro: GNU Astronomy Utilities

    Science.gov (United States)

    Akhlaghi, Mohammad

    2018-01-01

    Gnuastro (GNU Astronomy Utilities) manipulates and analyzes astronomical data. It is an official GNU package of a large collection of programs and C/C++ library functions. Command-line programs perform arithmetic operations on images, convert FITS images to common types like JPG or PDF, convolve an image with a given kernel or matching of kernels, perform cosmological calculations, crop parts of large images (possibly in multiple files), manipulate FITS extensions and keywords, and perform statistical operations. In addition, it contains programs to make catalogs from detection maps, add noise, make mock profiles with a variety of radial functions using monte-carlo integration for their centers, match catalogs, and detect objects in an image among many other operations. The command-line programs share the same basic command-line user interface for the comfort of both the users and developers. Gnuastro is written to comply fully with the GNU coding standards and integrates well with all Unix-like operating systems. This enables astronomers to expect a fully familiar experience in the source code, building, installing and command-line user interaction that they have seen in all the other GNU software that they use. Gnuastro's extensive library is included for users who want to build their own unique programs.

  11. Partial PIC-MRC Receiver Design for Single Carrier Block Transmission System over Multipath Fading Channels

    Directory of Open Access Journals (Sweden)

    Juinn-Horng Deng

    2012-01-01

    Full Text Available Single carrier block transmission (SCBT system has become one of the most popular modulation systems due to its low peak-to-average power ratio (PAPR, and it is gradually considered to be used for uplink wireless communication systems. In this paper, a low complexity partial parallel interference cancellation (PIC with maximum ratio combining (MRC technology is proposed to use for receiver to combat the intersymbol interference (ISI problem over multipath fading channel. With the aid of MRC scheme, the proposed partial PIC technique can effectively perform the interference cancellation and acquire the benefit of time diversity gain. Finally, the proposed system can be extended to use for multiple antenna systems to provide excellent performance. Simulation results reveal that the proposed low complexity partial PIC-MRC SIMO system can provide robust performance and outperform the conventional PIC and the iterative frequency domain decision feedback equalizer (FD-DFE systems over multipath fading channel environment.

  12. A Question and Answer Guide to Astronomy

    Science.gov (United States)

    Christian, Carol; Roy, Jean-René

    2017-03-01

    Preface; 1. The sky viewed from Earth; 2. The Earth and Moon system; 3. The Solar System; 4. Stars and stellar systems; 5. Galaxies and the Universe; 6. Life in the Universe; 7. Amateur astronomy; 8. Telescopes and instruments; Unit conversion and basic physical and astronomical measurements; References; Bibliography; Index.

  13. Radio Wavelength Studies of the Galactic Center Source N3, Spectroscopic Instrumentation For Robotic Telescope Systems, and Developing Active Learning Activities for Astronomy Laboratory Courses

    Science.gov (United States)

    Ludovici, Dominic Alesio

    2017-08-01

    The mysterious radio source N3 appears to be located within the vicinity of the Radio Arc region of the Galactic Center. To investigate the nature of this source, we have conducted radio observations with the VLA and the VLBA. Continuum observations between 2 and 50 GHz reveal that N3 is an extremely compact and bright source with a non-thermal spectrum. Molecular line observations with the VLA reveal a compact molecular cloud adjacent to N3 in projection. The properties of this cloud are consistent with other galactic center clouds. We are able to rule out several hypotheses for the nature of N3, though a micro-blazar origin cannot be ruled out. Robotic Telescope systems are now seeing widespread deployment as both teaching and research instruments. While these systems have traditionally been able to produce high quality images, these systems have lacked the capability to conduct spectroscopic observations. To enable spectroscopic observations on the Iowa Robotic Observatory, we have developed a low cost (˜ 500), low resolution (R ˜ 300) spectrometer which mounts inside a modified filter wheel and a moderate cost (˜ 5000), medium resolution (R ˜ 8000) fiber-fed spectrometer. Software has been developed to operate both instruments robotically and calibration pipelines are being developed to automate calibration of the data. The University of Iowa offers several introductory astronomy laboratory courses taken by many hundreds of students each semester. To improve student learning in these laboratory courses, we have worked to integrate active learning into laboratory activities. We present the pedagogical approaches used to develop and update the laboratory activities and present an inventory of the current laboratory exercises. Using the inventory, we make observations of the strengths and weaknesses of the current exercises and provide suggestions for future refinement of the astronomy laboratory curriculum.

  14. Receiver IQ mismatch estimation in PDM CO-OFDM system using training symbol

    Science.gov (United States)

    Peng, Dandan; Ma, Xiurong; Yao, Xin; Zhang, Haoyuan

    2017-07-01

    Receiver in-phase/quadrature (IQ) mismatch is hard to mitigate at the receiver via using conventional method in polarization division multiplexed (PDM) coherent optical orthogonal frequency division multiplexing (CO-OFDM) system. In this paper, a novel training symbol structure is proposed to estimate IQ mismatch and channel distortion. Combined this structure with Gram Schmidt orthogonalization procedure (GSOP) algorithm, we can get lower bit error rate (BER). Meanwhile, based on this structure one estimation method is deduced in frequency domain which can achieve the estimation of IQ mismatch and channel distortion independently and improve the system performance obviously. Numerical simulation shows that the proposed two methods have better performance than compared method at 100 Gb/s after 480 km fiber transmission. Besides, the calculation complexity is also analyzed.

  15. FPGA-Based Communications Receivers for Smart Antenna Array Embedded Systems

    Directory of Open Access Journals (Sweden)

    Millar James

    2006-01-01

    Full Text Available Field-programmable gate arrays (FPGAs are drawing ever increasing interest from designers of embedded wireless communications systems. They outpace digital signal processors (DSPs, through hardware execution of a wide range of parallelizable communications transceiver algorithms, at a fraction of the design and implementation effort and cost required for application-specific integrated circuits (ASICs. In our study, we employ an Altera Stratix FPGA development board, along with the DSP Builder software tool which acts as a high-level interface to the powerful Quartus II environment. We compare single- and multibranch FPGA-based receiver designs in terms of error rate performance and power consumption. We exploit FPGA operational flexibility and algorithm parallelism to design eigenmode-monitoring receivers that can adapt to variations in wireless channel statistics, for high-performing, inexpensive, smart antenna array embedded systems.

  16. FPGA-Based Communications Receivers for Smart Antenna Array Embedded Systems

    Directory of Open Access Journals (Sweden)

    James Millar

    2006-10-01

    Full Text Available Field-programmable gate arrays (FPGAs are drawing ever increasing interest from designers of embedded wireless communications systems. They outpace digital signal processors (DSPs, through hardware execution of a wide range of parallelizable communications transceiver algorithms, at a fraction of the design and implementation effort and cost required for application-specific integrated circuits (ASICs. In our study, we employ an Altera Stratix FPGA development board, along with the DSP Builder software tool which acts as a high-level interface to the powerful Quartus II environment. We compare single- and multibranch FPGA-based receiver designs in terms of error rate performance and power consumption. We exploit FPGA operational flexibility and algorithm parallelism to design eigenmode-monitoring receivers that can adapt to variations in wireless channel statistics, for high-performing, inexpensive, smart antenna array embedded systems.

  17. What next for astronomy?

    Science.gov (United States)

    Williams, Robert

    2009-12-01

    "Astronomy is in the midst of a golden age," wrote Catherine Cesarsky, my predecessor as president of the International Astronomical Union (IAU), earlier this year in Physics World (March pp22-24). I believe that is certainly true and it is an opportunity that we must take full advantage of. Astronomy is one of the great ways to bring science to the public - the images of the universe obtained using the Hubble Space Telescope, for example, are full of beauty. Astronomy is all about us. Indeed, the Earth and the life on it have developed from the cosmos, and the sky is the one laboratory that all humanity shares equally and that is accessible to all. There is little about the subject that appeals to fear - except, perhaps, the occasional killer asteroid. So what better science to inspire and educate people that what we do not know is definitely worth knowing?

  18. Astronomy in Australia

    Science.gov (United States)

    Watson, F.; Couch, W.

    2017-12-01

    Australians have watched the sky for tens of thousands of years. The nineteenth century saw the foundation of government observatories in capital cities such as Sydney and Melbourne. While early twentieth-century astronomy focused largely on solar physics, the advent of radio astronomy at the end of the Second World War enabled Australia to take a leading role in the new science, with particular emphasis on low-frequency studies. Today, the radio quietness of its outback interior provides an excellent location for the Australian core of the Square Kilometre Array. Australian optical astronomy has flourished since the 1960s, with the 3.9-metre Anglo-Australian Telescope becoming the principal national facility in 1974. Access to ESO’s facilities at the La Silla Paranal Observatory is warmly welcomed by all Australian astronomers.

  19. Solar Central Receiver Hybrid Power Systems sodium-cooled receiver concept. Final report. Volume II, Book 2. Conceptual design, Sections 5 and 6

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-01-01

    The overall, long-term objective of the Solar Central Receiver Hybrid Power System program is to identify, characterize, and ultimately demonstrate the viability and cost effectiveness of solar/fossil, steam Rankine cycle, hybrid power systems that: (1) consist of a combined solar central receiver energy source and a nonsolar energy source at a single, common site, (2) may operate in the base, intermediate, and peaking capacity modes, (3) produce the rated output independent of variations in solar insolation, (4) provide a significant savings (50% or more) in fuel consumption, and (5) produce power at the minimum possible cost in mills/kWh. It is essential that these hybrid concepts be technically feasible and economically competitive with other systems in the near to mid-term time period (1985-1990) on a commercial scale. The program objective for Phase I is to identify and conceptually characterize solar/fossil steam Rankine cycle, commercial-scale, power plant systems that are economically viable and technically feasible. This volume contains the detailed conceptual design and cost/performance estimates and an assessment of the commercial scale solar central receiver hybrid power system. (WHK)

  20. Test plan for qualification testing of the 241-SY-101 Flexible Receiver System

    International Nuclear Information System (INIS)

    Ritter, G.A.

    1994-01-01

    A mixer pump was installed in tank 241-SY-101 on July 3, 1993, to support hydrogen mitigation testing. This test mixer pump has proven to be very successful in mitigating the large gas releases, or ''burps,'' from the tank waste. Therefore, a decision has been made to fabricate a spare pump that will be installed upon failure of the existing test pump. Before replacement activities can be initiated, equipment must be available to remove the existing pump. A pump removal system is currently being designed and fabricated that will support the retrieval, transportation and disposal of the existing pump. The Equipment Removal System consists of six major components: the flexible receiver system (FRS), the equipment storage container, the container strongback system, the container transport trailer, the support cranes, and the pump washdown system

  1. Women in Astronomy Workshop Report

    OpenAIRE

    Brough, Sarah; Bauer, Amanda E.; Brooks, Kate; Hopkins, Andrew; Maddison, Sarah

    2011-01-01

    Here we report on the Women in Astronomy Workshop (http://asawomeninastronomy.org/meetings/wia2011/), which was held on 13 May 2011 in Sydney, Australia. The workshop was organised by the Astronomical Society of Australia's Chapter on Women in Astronomy, to discuss some of the issues that face women in astronomy and make recommendations to help support the success of women in Australian astronomy but came to broader conclusions that have value for the whole astronomical community. The worksho...

  2. Journal of Astrophysics and Astronomy | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Astrophysics and Astronomy. Gireesh C. Joshi. Articles written in Journal of Astrophysics and Astronomy. Volume 38 Issue 4 December 2017 pp 72 Research Article. Identification of Stellar Sequences in Various Stellar Systems: ESO65-SC03, Teutsch 106, Turner 6 · Gireesh C. Joshi.

  3. Journal of Astrophysics and Astronomy | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    2016-01-27

    Jan 27, 2016 ... Home; Journals; Journal of Astrophysics and Astronomy. M. M. Lame'e. Articles written in Journal of Astrophysics and Astronomy. Volume 31 Issue 2 June 2010 pp 97-104. Photometric Observation and Light Curve Analysis of Binary System ER-Orionis · M. M. Lame'e B. Javanmardi N. Riazi · More Details ...

  4. Journal of Astrophysics and Astronomy | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Astrophysics and Astronomy. Sergey V. Ershkov. Articles written in Journal of Astrophysics and Astronomy. Volume 38 Issue 1 March 2017 pp 5 Research Article. Forbidden Zones for Circular Regular Orbits of the Moons in Solar System, R3BP · Sergey V. Ershkov · More Details Abstract Fulltext ...

  5. Astronomy in Iraq

    Science.gov (United States)

    Alsabti, A. W.

    2006-08-01

    The history of modern Iraqi astronomy is reviewed. During the early 1970's Iraqi astronomy witnessed significant growth through the introduction of the subject at university level and extensively within the school curriculum. In addition, astronomy was popularised in the media, a large planetarium was built in Baghdad, plus a smaller one in Basra. Late 1970 witnessed the construction of the Iraqi National Observatory at Mount Korek in Iraqi Kurdistan. The core facilities of the Observatory included 3.5-meter and 1.25-meter optical telescopes, and a 30-meter radio telescope for millimetre wavelength astronomy. The Iraqi Astronomical Society was founded and Iraq joined the IAU in 1976. During the regime of Saddam Hussain in the 1980's, the Observatory was attacked by Iranian artillery during the Iraq-Iran war, and then again during the second Gulf war by the US air force. Years of sanctions during the 1990's left Iraq cut off from the rest of the international scientific community. Subscriptions to astronomical journals were halted and travel to conferences abroad was virtually non-existent. Most senior astronomers left the country for one reason or another. Support from expatriate Iraqi astronomers existed (and still exists) however, this is not sufficient. Recent changes in Iraq, and the fall of Saddam's regime, has meant that scientific communication with the outside world has resumed to a limited degree. The Ministry of Higher Education in Baghdad, Baghdad University and the Iraqi National Academy of Science, have all played active roles in re-establishing Iraqi astronomy and re-building the damaged Observatory at Mount Korek. More importantly the University of Sallahudin in Erbil, capital of Iraqi Kurdistan, has taken particular interest in astronomy and the Observatory. Organized visits to the universities, and also to the Observatory, have given us a first-hand assessment of the scale of the damage to the Observatory, as well as the needs of astronomy teaching

  6. Gamma ray astronomy

    International Nuclear Information System (INIS)

    Fichtel, C.E.

    1975-01-01

    The first certain detection of celestial high energy gamma rays came from a satellite experiment flown on the third Orbiting Solar Observatory (OSO-111). A Gamma ray spark chamber telescope with substantively greater sensitivity and angular resolution (a few degrees) flown on the second Small Astronomy Satellite (SAS-II) has now provided a better picture of the gamma ray sky, and particularly the galactic plane and pulsars. This paper will summarize the present picture of gamma ray astronomy as it has developed at this conference from measurements made with experiments carried out on balloons, those remaining on the ground, and ones flown on satellites. (orig.) [de

  7. Communicating astronomy with the public for scientists

    Science.gov (United States)

    Girola, R.

    2015-03-01

    This article intends to convey the improvement regarding the knowledge exchange in the astronomical field through an improvement in the quality of professional communication between researchers, teachers and the like whose job is to broadcast astronomical concepts. It has been a couple of years since the difficulty of communicating astronomical concepts decreased due to institutional projects, schools and education systems. Inside the education system, the need to include astronomy as an innovative element in curricula has become obvious. Outside, an informal public interested in astronomy became greater in number and began to be fostered by different organizations which spread their astronomical knowledge via workshops and demonstrations.

  8. Drive transmission system between a driving organ and a receiver organ

    International Nuclear Information System (INIS)

    Guillot, J.F.

    1985-01-01

    The present invention applies to the control rods of a water cooled nuclear reactor. The drive transmission system is disposed on the internal kinematic chain, between the control rod which is the receiver organ, and the driving organ. The control rod translation is obtained from a motion of rotation transformed in a motion of translation by means of a screw-nut system. The present invention prevents from control rod ejection in case of depressurization of the vessel containing the control rod drives or in case of reactor upsetting when it is embarked [fr

  9. A polarization-division multiplexing SSB-OFDM system with beat interference cancellation receivers

    Science.gov (United States)

    Yang, Peiling; Ma, Jianxin; Zhang, Junyi

    2018-06-01

    In this paper, we have proposed a polarization-division multiplexing (PDM) single-sideband optical orthogonal frequency division multiplexing (SSB-OOFDM) scheme with signal-signal beat interference cancellation receivers with balanced detection (ICRBD). This system can double channel capacity and improve spectrum efficiency (SE) with the reduced guard band (GB) due to the PDM. Multiple input multiple output (MIMO) technique is used to solve polarization mode dispersion (PMD) associated with channel estimation and equalization. By simulation, we demonstrate the efficacy of the proposed technique for a 2 ×40 Gbit/s 16-QAM SSB-PDM-OOFDM system according to the error vector magnitude (EVM) and the constellation diagrams.

  10. Solar central receiver hybrid power system, Phase I. Volume 3. Appendices. Final technical report, October 1978-August 1979

    Energy Technology Data Exchange (ETDEWEB)

    None

    1979-09-01

    A design study for a central receiver/fossil fuel hybrid power system using molten salts for heat transfer and heat storage is presented. This volume contains the appendices: (A) parametric salt piping data; (B) sample heat exchanger calculations; (C) salt chemistry and salt/materials compatibility evaluation; (D) heliostat field coordinates; (E) data lists; (F) STEAEC program input data; (G) hybrid receiver design drawings; (H) hybrid receiver absorber tube thermal math model; (I) piping stress analysis; (J) 100-MWe 18-hour storage solar central receiver hybrid power system capital cost worksheets; and (K) 500-MWe 18-hour solar central receiver hybrid power system cost breakdown. (WHK)

  11. The Cambridge encyclopaedia of astronomy

    CERN Document Server

    1977-01-01

    Astronomy has been transformed in the last two decades by a series of dramatic discoveries that have left most reference books completely out of date. The Cambridge Encyclopaedia of Astronomy presents a broadly based survey of the whole of astronomy which places emphasis on these critical new findings.

  12. Quickly Creating Interactive Astronomy Illustrations

    Science.gov (United States)

    Slater, Timothy F.

    2015-01-01

    An innate advantage for astronomy teachers is having numerous breathtaking images of the cosmos available to capture students' curiosity, imagination, and wonder. Internet-based astronomy image libraries are numerous and easy to navigate. The Astronomy Picture of the Day, the Hubble Space Telescope image archive, and the NASA Planetary…

  13. School-Based Extracurricular Astronomy

    Science.gov (United States)

    Stanger, Jeffrey J.

    2010-01-01

    The International Year of Astronomy in 2009 focused considerable public attention on Astronomy and generated valuable resources for educators. These activities are an effective vehicle for promoting Science to students and to the wider school community. The most engaging practical astronomy activities are best delivered with sustained support from…

  14. Teaching Astronomy in UK Schools

    Science.gov (United States)

    Roche, Paul; Roberts, Sarah; Newsam, Andy; Barclay, Charles

    2012-01-01

    This article attempts to summarise the good, bad and (occasionally) ugly aspects of teaching astronomy in UK schools. It covers the most common problems reported by teachers when asked about covering the astronomy/space topics in school. Particular focus is given to the GCSE Astronomy qualification offered by Edexcel (which is currently the…

  15. Performance of a nonlinear receiver for the ultrashort-pulse optical CDMA system

    Science.gov (United States)

    Ni, Bin; Lehnert, James S.

    2005-09-01

    At the receiver of an ultrashort-pulse optical code-division multiple-access (OCDMA) system, a nonlinear thresholder is needed to discriminate between the correctly decoded short pulse and the interference that appears to be a pseudorandom signal. It has been demonstrated that the self phase modulation (SPM) effect can be used to realize this nonlinear thresholder. The performance of a system that exploits this phenomenon is analyzed in this paper. If the spreading code is random, the electrical field of the interfering signal from the multiple users can be shown to be a complex Gaussian random process. The broadened power spectral density (PSD) function caused by the SPM effect can be calculated. When "1" is transmitted, the correctly decoded signal from the desired user, which is a deterministic waveform, is added to the Gaussian random process. Beating between the two signals causes random fluctuations in the power. Since the strength of the SPM effect is proportional to the variation rate of power, the broadened signal spectrum will appear random. The Monte Carlo method is used to obtain the properties of the decision statistic. Finally, the bit-error rate (BER) is calculated, and the simulation results are presented. The result reveals that the performance of the SPM-based nonlinear receiver can outperform the ideal linear receiver in some circumstances.

  16. Decision support system for determining Bantuan Siswa Miskin (BSM) receivers with profile matching method

    Science.gov (United States)

    Situmorang, B. H.; Pibriana, E.; Tosida, E. T.

    2018-03-01

    Bantuan Siswa Miskin (BSM) is a National Programs aimed at eliminating the barriers of poor students participating to school by helping poor students gain access to appropriate education services, prevent dropping out of school, attract poor students back to school, assis students in providing for learning activities, support the Nine Years Basic Education (and even up to senior high school) program, as well as helping to smooth the school programs [1]. Decision Support System is made by applying Profile Matching method to assist teachers or school operators in SMP PGRI Ciasmara in selecting prospective recipients of BSM program and providing recommendations in decision making. Profile Matching is used to compare the actual data value of a profile to be assessed by the expected profile value, so that it can be known the difference of competence (also called GAP). If the resulting value of GAP is smaller then the weight of value will be greater, which means it has a greater chance to be recommended as a potential recipient of the BSM program. Decision Support System for determining BSM receivers is only choosing the right alternatives to receive BSM according to the BSM quota given to SMP PGRI Ciasmara. The right alternatives to receive this BSM is the highest ranking alternatives.

  17. The handy astronomy answer book

    CERN Document Server

    Liu, PhD, Charles

    2013-01-01

    From planetary movements and the exploration of our solar system to black holes and dark matter, this comprehensive reference simplifies all aspects of astronomy with an approachable question-and-answer format. With chapters broken into various astronomical studies—including the universe, galaxies, planets, and space exploration—this fully updated resource is an ideal companion for students, teachers, and amateur astronomers, answering more than 1,000 questions, such as Is the universe infinite? What would happen to you if you fell onto a black hole? What are the basic concepts of Einstein's special theory of relativity? and Who was the first person in space?.

  18. Waste Receiving and Processing (WRAP) Facility Public Address System Review Findings

    International Nuclear Information System (INIS)

    HUMPHRYS, K.L.

    1999-01-01

    Public address system operation at the Waste Receiving and Processing (WRAP) facility was reviewed. The review was based on an Operational Readiness Review finding that public address performance was not adequate in parts of the WRAP facility. Several improvements were made to the WRAP Public Address (PA) system to correct the deficiencies noted. Speaker gain and position was optimized. A speech processor was installed to boost intelligibility in high noise areas. Additional speakers were added to improve coverage in the work areas. The results of this evaluation indicate that further PA system enhancements are not warranted. Additional speakers cannot compensate for the high background sound and high reverberation levels found in the work areas. Recommendations to improve PA system intelligibility include minor speaker adjustments, enhanced PA announcement techniques, and the use of sound reduction and abatement techniques where economically feasible

  19. OVERVIEW OF THE ATACAMA COSMOLOGY TELESCOPE: RECEIVER, INSTRUMENTATION, AND TELESCOPE SYSTEMS

    International Nuclear Information System (INIS)

    Swetz, D. S.; Devlin, M. J.; Dicker, S. R.; Ade, P. A. R.; Amiri, M.; Battistelli, E. S.; Burger, B.; Halpern, M.; Hasselfield, M.; Appel, J. W.; Essinger-Hileman, T.; Fisher, R. P.; Fowler, J. W.; Hincks, A. D.; Jarosik, N.; Chervenak, J.; Doriese, W. B.; Hilton, G. C.; Irwin, K. D.; Duenner, R.

    2011-01-01

    The Atacama Cosmology Telescope was designed to measure small-scale anisotropies in the cosmic microwave background and detect galaxy clusters through the Sunyaev-Zel'dovich effect. The instrument is located on Cerro Toco in the Atacama Desert, at an altitude of 5190 m. A 6 m off-axis Gregorian telescope feeds a new type of cryogenic receiver, the Millimeter Bolometer Array Camera. The receiver features three 1000-element arrays of transition-edge sensor bolometers for observations at 148 GHz, 218 GHz, and 277 GHz. Each detector array is fed by free space millimeter-wave optics. Each frequency band has a field of view of approximately 22' x 26'. The telescope was commissioned in 2007 and has completed its third year of operations. We discuss the major components of the telescope, camera, and related systems, and summarize the instrument performance.

  20. Overview of the Atacama Cosmology Telescope: Receiver, Instrumentation, and Telescope Systems

    Science.gov (United States)

    Swetz, D. S.; Ade, P. A. R.; Amiri, M.; Appel, J. W.; Battistelli, E. S.; Burger, B.; Chervenak, J.; Devlin, M. J.; Dicker, S. R.; Doriese, W. B.; Dünner, R.; Essinger-Hileman, T.; Fisher, R. P.; Fowler, J. W.; Halpern, M.; Hasselfield, M.; Hilton, G. C.; Hincks, A. D.; Irwin, K. D.; Jarosik, N.; Kaul, M.; Klein, J.; Lau, J. M.; Limon, M.; Marriage, T. A.; Marsden, D.; Martocci, K.; Mauskopf, P.; Moseley, H.; Netterfield, C. B.; Niemack, M. D.; Nolta, M. R.; Page, L. A.; Parker, L.; Staggs, S. T.; Stryzak, O.; Switzer, E. R.; Thornton, R.; Tucker, C.; Wollack, E.; Zhao, Y.

    2011-06-01

    The Atacama Cosmology Telescope was designed to measure small-scale anisotropies in the cosmic microwave background and detect galaxy clusters through the Sunyaev-Zel'dovich effect. The instrument is located on Cerro Toco in the Atacama Desert, at an altitude of 5190 m. A 6 m off-axis Gregorian telescope feeds a new type of cryogenic receiver, the Millimeter Bolometer Array Camera. The receiver features three 1000-element arrays of transition-edge sensor bolometers for observations at 148 GHz, 218 GHz, and 277 GHz. Each detector array is fed by free space millimeter-wave optics. Each frequency band has a field of view of approximately 22' × 26'. The telescope was commissioned in 2007 and has completed its third year of operations. We discuss the major components of the telescope, camera, and related systems, and summarize the instrument performance.

  1. Assessment of Compatibility between Ultrawideband (UWB) Systems and Global Positioning System (GPS) Receivers

    National Research Council Canada - National Science Library

    Anderson, David

    2001-01-01

    ...) of the proposed UWB transmitting devices to those spectrum-dependent systems currently in operation The NTIA, as the Executive Branch agency principally responsible for developing and articulating...

  2. Long Length Contaminated Equipment Retrieval System Receiver Trailer and Transport Trailer Operations and Maintenance Manual

    International Nuclear Information System (INIS)

    DALE, R.N.

    2000-01-01

    A system to accommodate the removal of long-length contaminated equipment (LLCE) from Hanford underground radioactive waste storage tanks was designed, procured, and demonstrated, via a project activity during the 1990s. The system is the Long Length Contaminated Equipment Removal System (LLCERS). LLCERS will be maintained and operated by Tank Farms Engineering and Operations organizations and other varied projects having a need for the system. The responsibility for the operation and maintenance of the LLCERS Receiver Trailer (RT) and Transport Trailer (TT) resides with the RPP Characterization Project Operations organization. The purpose of this document is to provide vendor supplied operating and maintenance (O and M) information for the RT and TT in a readily retrievable form. This information is provided this way instead of in a vendor information (VI) file to maintain configuration control of the operations baseline as described in RPP-6085, ''Configuration Management Plan for Long Length Contaminated Equipment Receiver and Transport Trailers''. Additional Operations Baseline documents are identified in RPP-6085

  3. Long Length Contaminated Equipment Retrieval System Receiver Trailer and Transport Trailer Operations and Maintenance Manual

    Energy Technology Data Exchange (ETDEWEB)

    DALE, R.N.

    2000-05-01

    A system to accommodate the removal of long-length contaminated equipment (LLCE) from Hanford underground radioactive waste storage tanks was designed, procured, and demonstrated, via a project activity during the 1990s. The system is the Long Length Contaminated Equipment Removal System (LLCERS). LLCERS will be maintained and operated by Tank Farms Engineering and Operations organizations and other varied projects having a need for the system. The responsibility for the operation and maintenance of the LLCERS Receiver Trailer (RT) and Transport Trailer (TT) resides with the RPP Characterization Project Operations organization. The purpose of this document is to provide vendor supplied operating and maintenance (O & M) information for the RT and TT in a readily retrievable form. This information is provided this way instead of in a vendor information (VI) file to maintain configuration control of the operations baseline as described in RPP-6085, ''Configuration Management Plan for Long Length Contaminated Equipment Receiver and Transport Trailers''. Additional Operations Baseline documents are identified in RPP-6085.

  4. Optimum quantum receiver for detecting weak signals in PAM communication systems

    Science.gov (United States)

    Sharma, Navneet; Rawat, Tarun Kumar; Parthasarathy, Harish; Gautam, Kumar

    2017-09-01

    This paper deals with the modeling of an optimum quantum receiver for pulse amplitude modulator (PAM) communication systems. The information bearing sequence {I_k}_{k=0}^{N-1} is estimated using the maximum likelihood (ML) method. The ML method is based on quantum mechanical measurements of an observable X in the Hilbert space of the quantum system at discrete times, when the Hamiltonian of the system is perturbed by an operator obtained by modulating a potential V with a PAM signal derived from the information bearing sequence {I_k}_{k=0}^{N-1}. The measurement process at each time instant causes collapse of the system state to an observable eigenstate. All probabilities of getting different outcomes from an observable are calculated using the perturbed evolution operator combined with the collapse postulate. For given probability densities, calculation of the mean square error evaluates the performance of the receiver. Finally, we present an example involving estimating an information bearing sequence that modulates a quantum electromagnetic field incident on a quantum harmonic oscillator.

  5. Identification and Support of Outstanding Astronomy Students

    Science.gov (United States)

    Stoev, A. D.; Bozhurova, E. S.

    2006-08-01

    The aims, organizational plan and syllabus of a specialized Astronomy School with a subject of training students for participation in the International Astronomy Olympiad, are presented. Thematic frame includes basic educational activities during the preparation and self-preparation of the students and their participation in astronomical Olympiads. A model of identification and selection of outstanding students for astronomical Olympiads has been developed. Examples of didactic systems of problems for development of mathematical, physical and astronomical skills are shown. The programme ends with individual training for solving problems on astronomy and astrophysics. Possibilities, which the characteristic, non-standard astronomical problems give for stimulating the creative and original thinking, are specified. Basic psychological condition for development of the students' creative potential - transformation of the cognitive content in emotional one - is demonstrated. The programme of identification and support of outstanding students on astronomy is realized in collaboration with The Ministry of Education and Science, Public Astronomical Observatories and Planetaria, Institute of Astronomy - Bulgarian Academy of Sciences, and The Union of Astronomers in Bulgaria.

  6. Bibliographic Resources for the Historian of Astronomy

    Science.gov (United States)

    Corbin, B. G.

    1999-12-01

    Many large library collections now have online bibliographic catalogs on the web. These provide many hidden resources for the historian of astronomy. Special searching techniques will allow the historian to scan bibliographic records of hundreds of entries relating to biographies of astronomers, collected works of astronomers, ancient and medieval astronomy and many other historical subjects. Abstract databases such as the Astrophysics Data System and ARIBIB are also adding much historical bibliographic information. ARIBIB will eventually contain scanned images of the Astronomischer Jahresbericht containing bibliographic entries for all literature of astronomy from 1899 to 1968 and Astronomy and Astrophysics Abstracts from 1969 to present. Commercial services such as UnCover and FirstSearch provide a means of reaching bibliographic entries for journal and book literature in the history of astronomy which were not easily located in the past. A broad overview of these collections and services will be given, and searching techniques for finding ``hidden" bibliographic data will be presented. Web page addresses will be given for all sources covered.

  7. Financing alternatives and incentives for solar-thermal central-receiver systems

    Energy Technology Data Exchange (ETDEWEB)

    Bos, P.B.

    1982-07-01

    As a result of various recently enacted incentive and regulatory legislation combined with the new administration policy and budgetary guidelines, the commercialization of solar thermal central receiver systems will involve financing alternatives other than conventional utility financing. This study was conducted to identify these potential financing alternatives and the associated requirements and impacts on the Department of Energy program. Based upon this analysis, it is concluded that the current alternative financing window is extremely short (through 1985), and that an extension or at the least a gradual phasing out, of the solar tax credits is necessary for the successful transfer of the central receiver technology to the private sector. Furthermore, throughout this time period, continued government support of the R and D activities is necessary to provide the necessary confidence in this technology for the private (financial) sector to underwrite this technology transfer. Consequently, even though the central receiver technology shows high promise for replacing a significant fraction of the oil/gas-fired utility industry peaking and intermediate generation, the current readiness status of this technology still requires further direct and indirect government support for a successful technology transfer. The direct government research and development support will provide the basis for a technological readiness and confidence, whereas the indirect tax incentive support serves to underwrite the extraordinary risks associated with the technology transfer. These support requirements need only be limited to and decreasing during this technology transfer phase, since as the systems approach successful full-scale commercialization, the extraordinary risks will be gradually eliminated. At the time of commercialization the system's value should be on a par with the installed system's cost.

  8. The Cost of Astronomy

    DEFF Research Database (Denmark)

    Dorch, Bertil F.

    Using Scopus and national sources, I have investigated the evolution of the cost of publishing in Danish astronomy on a fine scale over a number of years. I find that the number of publications per year from Danish astronomers increased by a factor of four during 15 years: naturally, the correspo......Using Scopus and national sources, I have investigated the evolution of the cost of publishing in Danish astronomy on a fine scale over a number of years. I find that the number of publications per year from Danish astronomers increased by a factor of four during 15 years: naturally......, the corresponding potential cost of publishing must have increased similarly. The actual realized cost of publishing in core journals are investigated for a high profile Danish astronomy research institutions. I argue that the situation is highly unstable if the current cost scenario continues, and I speculate...... that Danish astronomy is risking a scholarly communication collapse due to the combination of increasing subscription cost, increased research output, and increased direct publishing costs related to Open access and other page charges....

  9. Gamma ray astronomy

    International Nuclear Information System (INIS)

    Broomhead, Laurent.

    1980-01-01

    The nuclear gamma astronomy is presented, in particular the Gamma Ray Observatory, an enormous eight tonnes machine fitted with gamma telescopes, scheduled for launching around 1985. It is thereby hoped to study the natural nuclear reactions which occur when stars explode [fr

  10. Teaching Astronomy Using Tracker

    Science.gov (United States)

    Belloni, Mario; Christian, Wolfgang; Brown, Douglas

    2013-01-01

    A recent paper in this journal presented a set of innovative uses of video analysis for introductory physics using Tracker. In addition, numerous other papers have described how video analysis can be a meaningful part of introductory courses. Yet despite this, there are few resources for using video analysis in introductory astronomy classes. In…

  11. Gamma ray astronomy

    International Nuclear Information System (INIS)

    Hillier, R.

    1984-01-01

    The book reviews the development of gamma ray astronomy over the past twenty five years. A large section of the book is devoted to the problems of background radiation and the design of detectors. Gamma rays from the sun, the galactic disc, the galaxy, and extra galactic sources; are also discussed. (U.K.)

  12. Astronomy and Creationism.

    Science.gov (United States)

    Morrison, David

    1982-01-01

    Discusses the effects on astronomy courses/curriculum if equal time were given to the concept that the universe was created in its present form about ten thousand years ago. Includes the full text on a resolution concerning creationism passed by the Board of Directors of the Astronomical Society of the Pacific. (Author/JN)

  13. The Cost of Astronomy

    DEFF Research Database (Denmark)

    Dorch, Bertil F.

    Using Scopus and national sources, I have investigated the evolution of the cost of publishing in Danish astronomy on a fine scale over a number of years. I find that the number of publications per year from Danish astronomers increased by a factor of four during 15 years: naturally, the correspo...

  14. Physics and astronomy

    CSIR Research Space (South Africa)

    Moraal, H

    2009-01-01

    Full Text Available The chapter is about physics and astronomy. The chapter gives a background about the origins of physics in South Africa. After the CSIR was founded in 1945, physics emerged as a nationwide and unified discipline. The authors show how physics...

  15. SymptomCare@Home: Developing an Integrated Symptom Monitoring and Management System for Outpatients Receiving Chemotherapy.

    Science.gov (United States)

    Beck, Susan L; Eaton, Linda H; Echeverria, Christina; Mooney, Kathi H

    2017-10-01

    SymptomCare@Home, an integrated symptom monitoring and management system, was designed as part of randomized clinical trials to help patients with cancer who receive chemotherapy in ambulatory clinics and often experience significant symptoms at home. An iterative design process was informed by chronic disease management theory and features of assessment and clinical decision support systems used in other diseases. Key stakeholders participated in the design process: nurse scientists, clinical experts, bioinformatics experts, and computer programmers. Especially important was input from end users, patients, and nurse practitioners participating in a series of studies testing the system. The system includes both a patient and clinician interface and fully integrates two electronic subsystems: a telephone computer-linked interactive voice response system and a Web-based Decision Support-Symptom Management System. Key features include (1) daily symptom monitoring, (2) self-management coaching, (3) alerting, and (4) nurse practitioner follow-up. The nurse practitioner is distinctively positioned to provide assessment, education, support, and pharmacologic and nonpharmacologic interventions to intensify management of poorly controlled symptoms at home. SymptomCare@Home is a model for providing telehealth. The system facilitates using evidence-based guidelines as part of a comprehensive symptom management approach. The design process and system features can be applied to other diseases and conditions.

  16. Multi-LED parallel transmission for long distance underwater VLC system with one SPAD receiver

    Science.gov (United States)

    Wang, Chao; Yu, Hong-Yi; Zhu, Yi-Jun; Wang, Tao; Ji, Ya-Wei

    2018-03-01

    In this paper, a multiple light emitting diode (LED) chips parallel transmission (Multi-LED-PT) scheme for underwater visible light communication system with one photon-counting single photon avalanche diode (SPAD) receiver is proposed. As the lamp always consists of multi-LED chips, the data rate could be improved when we drive these multi-LED chips parallel by using the interleaver-division-multiplexing technique. For each chip, the on-off-keying modulation is used to reduce the influence of clipping. Then a serial successive interference cancellation detection algorithm based on ideal Poisson photon-counting channel by the SPAD is proposed. Finally, compared to the SPAD-based direct current-biased optical orthogonal frequency division multiplexing system, the proposed Multi-LED-PT system could improve the error-rate performance and anti-nonlinearity performance significantly under the effects of absorption, scattering and weak turbulence-induced channel fading together.

  17. Strategies for Teaching Astronomy

    Science.gov (United States)

    Bennett, J.

    2000-12-01

    No matter whether you are teaching school children, undergraduates, or colleagues, a few key strategies are always useful. I will present and give examples for the following five key strategies for teaching astronomy. 1. Provide a Contextual Framework: It is much easier to learn new facts or concepts if they can be ``binned" into some kind of pre-existing mental framework. Unless your listeners are already familiar with the basic ideas of modern astronomy (such as the hierarchy of structure in the universe, the scale of the universe, and the origin of the universe), you must provide this before going into the details of how we've developed this modern picture through history. 2. Create Conditions for Conceptual Change: Many people hold misconceptions about astronomical ideas. Therefore we cannot teach them the correct ideas unless we first help them unlearn their prior misconceptions. 3. Make the Material Relevant: It's human nature to be more interested in subjects that seem relevant to our lives. Therefore we must always show students the many connections between astronomy and their personal concerns, such as emphasizing how we are ``star stuff" (in the words of Carl Sagan), how studying other planets helps us understand our own, and so on. 4. Limit Use of Jargon: The number of new terms in many introductory astronomy books is larger than the number of words taught in many first courses in foreign language. This means the books are essentially teaching astronomy in a foreign language, which is a clear recipe for failure. We must find ways to replace jargon with plain language. 5. Challenge Your Students: Don't dumb your teaching down; by and large, students will rise to meet your expectations, as long as you follow the other strategies and practice good teaching.

  18. Monitored Retrievable Storage conceptual system study: dry receiving and handling facility

    International Nuclear Information System (INIS)

    1984-01-01

    A preconceptual design and estimate for a MRS receiving and handling (R and H) facility at a hypothetical site in the United States are presented. The facility consists of a receiving and handling building plus associated operating buildings, system, and site development features. The R and H building and the supporting buildings and site development features are referred to as the R and H area. Adjoining the R and H area will be an interim waste storage area currently being considered by others. The desirability of building a full capacity (3000-MTU) MRS facility initially versus adding additional capacity at a later date in a phased construction program was investigated. Several advantages of phased construction include incorporation of new designs, modification of receiving-handling-packaging, and changes in regulatory requirements or the waste management program which may develop following startup and operation of an 1800-MTU MRS facility. The cost of a 3000-MTU MRS facility constructed initially was estimated at $193,200,000. If a phased construction program was implemented, including escalation to the mid-point of Phase 2 construction, a capital expenditure of $215,300,000 is estimated - a cost penalty of $22,100,000 or about 11% for phased construction

  19. Advanced Receiver Design for Mitigating Multiple RF Impairments in OFDM Systems: Algorithms and RF Measurements

    Directory of Open Access Journals (Sweden)

    Adnan Kiayani

    2012-01-01

    Full Text Available Direct-conversion architecture-based orthogonal frequency division multiplexing (OFDM systems are troubled by impairments such as in-phase and quadrature-phase (I/Q imbalance and carrier frequency offset (CFO. These impairments are unavoidable in any practical implementation and severely degrade the obtainable link performance. In this contribution, we study the joint impact of frequency-selective I/Q imbalance at both transmitter and receiver together with channel distortions and CFO error. Two estimation and compensation structures based on different pilot patterns are proposed for coping with such impairments. The first structure is based on preamble pilot pattern while the second one assumes a sparse pilot pattern. The proposed estimation/compensation structures are able to separate the individual impairments, which are then compensated in the reverse order of their appearance at the receiver. We present time-domain estimation and compensation algorithms for receiver I/Q imbalance and CFO and propose low-complexity algorithms for the compensation of channel distortions and transmitter IQ imbalance. The performance of the compensation algorithms is investigated with computer simulations as well as with practical radio frequency (RF measurements. The performance results indicate that the proposed techniques provide close to the ideal performance both in simulations and measurements.

  20. Students Across Texas Celebrate Astronomy Day

    Science.gov (United States)

    Preston, S.; Wetzel, M.; Hemenway, M. K.

    2010-08-01

    Over the past three years, McDonald Observatory has offered special Astronomy Day videoconference programs to students across Texas—the second largest state in the U.S. (Only Alaska is larger). Videoconferencing allows many students and teachers access to our Observatory, which is remotely located 180 miles (290 kilometers) from any major city. McDonald Observatory partners with Connect2Texas to advertise the Astronomy Day event. Connect2Texas provides the electronic bridge between schools and the Observatory. They also provide an online evaluation for teachers to complete. In 2009 the Astronomy Day videoconference celebrated the International Year of Astronomy and the historic observations made by Galileo Galilei. During the videoconference, the classes explore the Moon or Venus by making real-time telescopic observations. Students also receive an introduction to the Observatory, an opportunity to perform an activity relating to Galileo's observations, and an interview with an astronomer. A website provides teachers pre-and post-video conference materials, instructions, and a certificate of completion that can be customized for each student. The website also lists content alignment with state science education standards.

  1. Naming asteroids for the popularisation of astronomy

    Science.gov (United States)

    Naranjo, O. A.

    2008-06-01

    We give a detailed description of how the naming of asteroids was used as a prize in competitions run by educational institutions and museums. There were two events, one in Venezuela and one in Brazil, which used this as an attractive alternative method for the popularisation of astronomy. The first competition, named Bautizo Espacial (Space Baptism), consisted of scientific stories written by high school students. The second, called Grande Desafio (Big Challenge), was a competition where teams of students were challenged to design and build prototype equipment to fight forest fires. Nationally, both events received wide publicity through newspapers, radio, TV and web pages, reaching many people in both countries. As part of both the events, several activities promoting the public knowledge of astronomy were held. The asteroids that were named in these competitions are just some of the many discovered in a search programme developed by the Group of Theoretical Astrophysics of University of Los Andes in Mérida, Venezuela (Grupo de Astrofisica Teórica de la Universidad de Los Andes) as a mainstream research programme. Finally, Asteroids for the Popularisation of Astronomy has been formally proposed to the IAU as a worldwide programme during the celebration of the International Year of Astronomy in 2009 (IYA2009).

  2. Improved Iterative Parallel Interference Cancellation Receiver for Future Wireless DS-CDMA Systems

    Directory of Open Access Journals (Sweden)

    Andrea Bernacchioni

    2005-04-01

    Full Text Available We present a new turbo multiuser detector for turbo-coded direct sequence code division multiple access (DS-CDMA systems. The proposed detector is based on the utilization of a parallel interference cancellation (PIC and a bank of turbo decoders. The PIC is broken up in order to perform interference cancellation after each constituent decoder of the turbo decoding scheme. Moreover, in the paper we propose a new enhanced algorithm that provides a more accurate estimation of the signal-to-noise-plus-interference-ratio used in the tentative decision device and in the MAP decoding algorithm. The performance of the proposed receiver is evaluated by means of computer simulations for medium to very high system loads, in AWGN and multipath fading channel, and compared to recently proposed interference cancellation-based iterative MUD, by taking into account the number of iterations and the complexity involved. We will see that the proposed receiver outperforms the others especially for highly loaded systems.

  3. Acceptance test report, 241-SY-101 Flexible Receiver System, Phase 3 testing

    International Nuclear Information System (INIS)

    Ritter, G.A.

    1995-01-01

    This document summarizes the results of the phase 3 acceptance test of the 241-SY-101 Flexible Receiver System (FRS). The purpose of this acceptance test is to verify the sealing integrity of the FRS to ensure that the release of waste and aerosols will be minimized during the removal of the test mixer pump from Tank 241-SY-101. The FRS is one of six major components of the Equipment Removal System, which has been designed to retrieve, transport, and store the mixer pump. This acceptance test was performed at the 306E Facility in the 300 area from January 10, 1995 to January 17, 1995. The Phase 3 test consisted of two parts. Part one was a water leak test of the seal between the blast shield and mock load distribution frame (LDF) to ensure that significant contamination of the pump pit and waste interaction with the aluminum impact-limiting material under the LDF are prevented during the pump removal operation. The second part of this acceptance test was an air leak test of the assembled flexible receiver system. The purpose of this test was to verify that the release of hazardous aerosols will be minimized if the tank dome pressure becomes slightly positive during the decontamination of the mixer pump

  4. An Assessment of Slacker Astronomy Outreach Results

    Science.gov (United States)

    Price, A.; Gay, P. L.; Searle, T.; Brissenden, G.

    2005-12-01

    Slacker Astronomy is a weekly podcast covering recent astronomical news in a humorous, irreverent manner while respecting the intelligence of the audience. This is a new approach to astronomical outreach both technically and stylistically. Using the Field-tested Learning Assessment Guide (FLAG) and the Quality Function Deployment (QFD) needs analysis survey system, we have have conducted an in-depth project to determine whether this new style is effective and what audience needs are outstanding. Slacker Astronomy currently has around 11,000 weekly listeners and was founded in February, 2005. Recordings and scripts are available to the public under the Creative Commons license at www.slackerastronomy.org.

  5. Solar Central Receiver Hybrid Power Systems sodium-cooled receiver concept. Final report. Volume II, Book 1. Conceptual design, Sections 1 through 4

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-01-01

    The overall, long-term objective of the Solar Central Receiver Hybrid Power System program is to identify, characterize, and ultimately demonstrate the viability and cost effectiveness of solar/fossil, steam Rankine cycle, hybrid power systems that: (1) consist of a combined solar central receiver energy source and a nonsolar energy source at a single, common site, (2) may operate in the base, intermediate, and peaking capacity modes, (3) produce the rated output independent of variations in solar insolation, (4) provide a significant savings (50% or more) in fuel consumption, and (5) produce power at the minimum possible cost in mills/kWh. It is essential that these hybrid concepts be technically feasible and economically competitive with other systems in the near to mid-term time period (1985-1990) on a commercial scale. The program objective for Phase I is to identify and conceptually characterize solar/fossil steam Rankine cycle, commercial-scale, power plant systems that are economically viable and technically feasible. This volume presents in detail the market analysis, parametric analysis, and the selection process for the preferred system. (WHK)

  6. High-temperature thermal storage systems for advanced solar receivers materials selections

    Science.gov (United States)

    Wilson, D. F.; Devan, J. H.; Howell, M.

    1990-01-01

    Advanced space power systems that use solar energy and Brayton or Stirling heat engines require thermal energy storage (TES) systems to operate continuously through periods of shade. The receiver storage units, key elements in both Brayton and Stirling systems, are designed to use the latent heat of fusion of phase-change materials (PCMs). The power systems under current consideration for near-future National Aeronautics and Space Administration space missions require working fluid temperatures in the 1100 to 1400 K range. The PCMs under current investigation that gave liquid temperatures within this range are the fluoride family of salts. However, these salts have low thermal conductivity, which causes large temperature gradients in the storage systems. Improvements can be obtained, however, with the use of thermal conductivity enhancements or metallic PCMs. In fact, if suitable containment materials can be found, the use of metallic PCMs would virtually eliminate the orbit associated temperature variations in TES systems. The high thermal conductivity and generally low volume change on melting of germanium and alloys based on silicon make them attractive for storage of thermal energy in space power systems. An approach to solving the containment problem, involving both chemical and physical compatibility, preparation of NiSi/NiSi2, and initial results for containment of germanium and NiSi/NiSi2, are presented.

  7. Influence of Load Modes on Voltage Stability of Receiving Network at DC/AC System

    Directory of Open Access Journals (Sweden)

    Mao Chizu

    2016-01-01

    Full Text Available This paper analyses influence of load modes on DC/AC system. Because of widespread use of HVDC, DC/AC system become more complex than before and the present modes used in dispatch and planning departments are not fit in simulation anymore. So it is necessary to find load modes accurately reflecting characteristics of the system. For the sake of the voltage stability, commutation failure, etc. the practical example of the receiving network in a large DC/AC system in China is simulated with BPA, and the influence of Classical Load Mode (CLM and Synthesis load model (SLM on simulation results is studies. Furthermore, some important parameters of SLM are varied respectively among an interval to analyse how they affect the system. According to this practical examples, the result is closely related to load modes and their parameters, and SLM is more conservative but more reasonable than the present modes. The consequences indicate that at critical states, micro variation in parameters may give rise to change in simulation results radically. Thus, correct mode and parameters are important to enhance simulation accuracy of DC/AC system and researches on how they affect the system make senses.

  8. Improving the efficiency of gas turbine systems with volumetric solar receivers

    International Nuclear Information System (INIS)

    Petrakopoulou, Fontina; Sánchez-Delgado, Sergio; Marugán-Cruz, Carolina; Santana, Domingo

    2017-01-01

    Highlights: • Study of small and large-scale solar-combined cycle plants with volumetric receivers. • Increase of inlet temperature of combustion air using solar energy. • The combustion exergy efficiency starts to decrease over a certain temperature. • Indications obtained from the energy and exergy analyses differ. - Abstract: The combustion process of gas turbine systems is typically associated with the highest thermodynamic inefficiencies among the system components. A method to increase the efficiency of a combustor and, consequently that of the gas turbine, is to increase the temperature of the entering combustion air. This measure reduces the consumption of fuel and improves the environmental performance of the turbine. This paper studies the incorporation of a volumetric solar receiver into existing gas turbines in order to increase the temperature of the inlet combustion air to 800 °C and 1000 °C. For the first time, detailed thermodynamic analyses involving both energy and exergy principles of both small-scale and large-scale hybrid (solar-combined cycle) power plants including volumetric receivers are realized. The plants are based on real gas turbine systems, the base operational characteristics of which are derived and reported in detail. It is found that the indications obtained from the energy and exergy analyses differ. The addition of the solar plant achieves an increase in the exergetic efficiency when the conversion of solar radiation into thermal energy (i.e., solar plant efficiency) is not accounted for in the definition of the overall plant efficiency. On the other hand, it is seen that it does not have a significant effect on the energy efficiency. Nevertheless, when the solar efficiency is included in the definition of the overall efficiency of the plants, the addition of the solar receiver always leads to an efficiency reduction. It is found that the exergy efficiency of the combustion chamber depends on the varying air

  9. Benefits of remote real-time side-effect monitoring systems for patients receiving cancer treatment.

    Science.gov (United States)

    Kofoed, Sarah; Breen, Sibilah; Gough, Karla; Aranda, Sanchia

    2012-03-05

    In Australia, the incidence of cancer diagnoses is rising along with an aging population. Cancer treatments, such as chemotherapy, are increasingly being provided in the ambulatory care setting. Cancer treatments are commonly associated with distressing and serious side-effects and patients often struggle to manage these themselves without specialized real-time support. Unlike chronic disease populations, few systems for the remote real-time monitoring of cancer patients have been reported. However, several prototype systems have been developed and have received favorable reports. This review aimed to identify and detail systems that reported statistical analyses of changes in patient clinical outcomes, health care system usage or health economic analyses. Five papers were identified that met these criteria. There was wide variation in the design of the monitoring systems in terms of data input method, clinician alerting and response, groups of patients targeted and clinical outcomes measured. The majority of studies had significant methodological weaknesses. These included no control group comparisons, small sample sizes, poor documentation of clinical interventions or measures of adherence to the monitoring systems. In spite of the limitations, promising results emerged in terms of improved clinical outcomes (e.g. pain, depression, fatigue). Health care system usage was assessed in two papers with inconsistent results. No studies included health economic analyses. The diversity in systems described, outcomes measured and methodological issues all limited between-study comparisons. Given the acceptability of remote monitoring and the promising outcomes from the few studies analyzing patient or health care system outcomes, future research is needed to rigorously trial these systems to enable greater patient support and safety in the ambulatory setting.

  10. Efficiency improvement of a concentrated solar receiver for water heating system using porous medium

    Science.gov (United States)

    Prasartkaew, Boonrit

    2018-01-01

    This experimental study aims at investigating on the performance of a high temperature solar water heating system. To approach the high temperature, a porous-medium concentrated solar collector equipped with a focused solar heliostat were proposed. The proposed system comprised of two parts: a 0.7x0.7-m2 porous medium receiver, was installed on a 3-m tower, and a focused multi-flat-mirror solar heliostat with 25-m2 aperture area. The porous medium used in this study was the metal swarf or metal waste from lathing process. To know how the system efficiency could be improved by using such porous medium, the proposed system with- and without-porous medium were tested and the comparative study was performed. The experimental results show that, using porous medium for enhancing the heat transfer mechanism, the system thermal efficiency was increased about 25%. It can be concluded that the efficiency of the proposed system can be substantially improved by using the porous medium.

  11. Conceptual design of an RTG Shipping and Receiving Facility Transportation System

    International Nuclear Information System (INIS)

    Black, S.J.; Gentzlinger, R.C.; Lujan, R.E.

    1994-01-01

    The conceptual design of an RTG Facility Transportation System which is part of the overall RTG Transportation System has been completed and is described in detail. The Facility Transportation System serves to provide locomotion, cooling, shock protection and data acquisition for the RTG package during onloading and offloading sequences. The RTG Shipping ampersand Receiving Facility Transportation System consists of a Transporter Subsystem, a Package Cooling Subsystem, and a Shock Limiting Transit Device Subsystem. The Transporter Subsystem is a custom designed welded steel cart combined with a pneumatically-driven hand tug for locomotion. The Package Cooling Subsystem provides five kilowatts of active liquid cooling via an on-board refrigeration system. The Shock Limiting Transit Device Subsystem consists of a consumable honeycomb anti-shock frame which provides shock protection for the 3855 kg (8500 LB) RTG package. These subsystems have been combined into an integrated system which will facilitate the offloading and onloading of the RTG Package into and out of the semitrailer as well as meet ALARA (as low as reasonably achievable) radiation exposure guidelines

  12. Conceptual design of an RTG shipping and receiving facility transportation system

    International Nuclear Information System (INIS)

    Black, S.J.; Gentzlinger, R.C.; Lujan, R.E.

    1995-01-01

    The conceptual design of an RTG Facility Transportation System which is part of the overall RTG Transportation System has been completed and is described in detail. The Facility Transportation System serves to provide locomotion, cooling, shock protection and data acquisition for the RTG package during onloading and offloading sequences. The RTG Shipping ampersand Receiving Facility Transportation System consists of a Transporter Subsystem, a Package Cooling Subsystem, and a Shock Limiting Transit Device Subsystem. The Transporter Subsystem is a custom designed welded steel cart combined with a pneumatically-driven hand tug for locomotion. The Package Cooling Subsystem provides five kilowatts of active liquid cooling via an on-board refrigeration system. The Shock Limiting Transit Device Subsystem consists of a consumable honeycomb anti-shock frame which provides shock protection for the 3855 kg (8500 LB) RTG package. These subsystems have been combined into an integrated system which will facilitate the offloading and onloading of the RTG Package into and out of the semitrailer as well as meet ALARA (as low as reasonably achievable) radiation exposure guidelines. copyright 1995 American Institute of Physics

  13. Tear Film and Ocular Surface Changes in Patients Receiving Systemic Isotretinoin

    Directory of Open Access Journals (Sweden)

    Ebru Nevin Çetin

    2013-10-01

    Full Text Available Purpose: Our aim in this study was to assess the ocular surface and tear film changes in acne vulgaris patients receiving systemic isotretinoin. Material and Method: Twenty-two eyes of 22 patients who received oral isotretinoin (roaccutane®, 0.7 mg/kg/day for nodular acne vulgaris were enrolled in this prospective study. Tear film break-up time (BUT, Schirmer 1 test scores with anesthesia, ocular surface disease index (OSDI scores and conjunctival impression cytology scores were recorded before treatment and at 3- and 6-month visits following the beginning of treatment. Results: BUT values decreased and OSDI scores significantly increased at 3 months after treatment (p=0.007 and p=0.018, paired samples test. Schirmer scores did not significantly change by isotretinoin treatment. Of 9 eyes with impression cytology specimens, 4 revealed normal conjunctival findings before treatment. At the 3rd month, there was an increase in the scores characterized by decrease of Goblet cells, and at 6 months of treatment, normal conjunctival findings did not exist in any of the patients (p=0.004, Friedman test. Discussion: Systemic isotretinoin treatment can cause alterations in the tear film and cause dry eye symptoms. (Turk J Ophthalmol 2013; 43: 309-12

  14. Highlights of Astronomy, Vol. 15

    Science.gov (United States)

    Corbett, Ian

    2010-11-01

    Preface; Part I. Gruber Cosmology Prize Lecture; Part II. Invited Discourses; Part III. Joint Discussions: 1. Dark matter in early-type galaxies Léon V. E. Koopmans and Tommaso Treu; 2. Diffuse light in galaxy clusters Magda Arnaboldi and Ortwin Gerhard; 3. Neutron stars - timing in extreme environments Tomaso Belloni, Mariano Méndez and Chengmin Zhang; 4. Progress in understanding the physics of Ap and related stars Margarida Cunha; 5. Modelling the Milky Way in the age of Gaia Annie C. Robin; 6. Time and astronomy Pascale Defraigne; 7. Astrophysical outflows and associated accretion phenomena Elisabete M. de Gouveia Dal Pino and Alex C. Raga; 8. Hot interstellar matter in elliptical galaxies Dong-Woo Kim and Silvia Pellegrini; 9. Are the fundamental constants varying with time? Paolo Molaro and Elisabeth Vangioni; 10. 3D views on cool stellar atmospheres - theory meets observation K. N. Nagendra, P. Bonifacio and H. G. Ludwig; 11. New advances in helio- and astero-seismology; 12. The first galaxies - theoretical predictions and observational clues; 13. Eta Carinae in the context of the most massive stars Theodore R. Gull and Augusto Damineli; 14. The ISM of galaxies in the far-infrared and sub-millimetre; 15. Magnetic fields in diffuse media Elisabete M. de Gouveia Dal Pino and Alex Lazarian; 16. IHY global campaign - whole heliosphere interval; Part IV. Special Sessions: SpS 1. IR and sub-mm spectroscopy - a new tool for studying stellar evolution Glenn Wahlgren, Hans Käufl and Florian Kerber; SpS 2. The international year of astronomy Pedro Russo, Catherine Cesarsky and Lars Lindberg Christensen; SpS 3. Astronomy in Antarctica in 2009 Michael G. Burton; SpS 4. Astronomy education between past and future J. P. De Greve; SpS 5. Accelerating the rate of astronomical discovery Ray P. Norris; SpS 6. Planetary systems as potential sites for life Régis Courtin, Alan Boss and Michel Mayor; SpS 7. Young stars, brown dwarfs, and protoplanetary disks Jane Gregorio

  15. Performance analysis of underlay cognitive multihop regenerative relaying systems with multiple primary receivers

    KAUST Repository

    Hyadi, Amal

    2013-12-01

    Multihop relaying is an efficient strategy to improve the connectivity and extend the coverage area of secondary networks in underlay cognitive systems. In this work, we provide a comprehensive performance study of cognitive multihop regenerative relaying systems in an underlay spectrum sharing scenario with the presence of multiple primary receivers. Both interference power and peak power constraints are taken into account. In our analysis, all the links are subject to independent, non-identically distributed Nakagami-m fading. We derive closed-form expressions for the outage probability, high-order amount of fading, bit error rate, symbol error rate, and ergodic capacity. Different scenarios are presented to illustrate the obtained results and Monte Carlo simulations confirm the accuracy of our analytical derivations. © 2013 IEEE.

  16. Paying for and receiving benefits from health services in South Africa: is the health system equitable?

    Science.gov (United States)

    Ataguba, John E; McIntyre, Di

    2012-03-01

    There is a global challenge for health systems to ensure equity in both the delivery and financing of health care. However, many African countries still do not have equitable health systems. Traditionally, equity in the delivery and the financing of health care are assessed separately, in what may be termed 'partial' analyses. The current debate on countries moving toward universal health systems, however, requires a holistic understanding of equity in both the delivery and the financing of health care. The number of studies combining these aspects to date is limited, especially in Africa. An assessment of overall health system equity involves assessing health care financing in relation to the principles of contributing to financing according to ability to pay and benefiting from health services according to need for care. Currently South Africa is considering major health systems restructuring toward a universal system. This paper examines together, for both the public and the private sectors, equity in the delivery and financing of health care in South Africa. Using nationally representative datasets and standard methodologies for assessing progressivity in health care financing and benefit incidence, this paper reports an overall progressive financing system but a pro-rich distribution of health care benefits. The progressive financing system is driven mainly by progressive private medical schemes that cover a small portion of the population, mainly the rich. The distribution of health care benefits is not only pro-rich, but also not in line with the need for health care; richer groups receive a far greater share of service benefits within both public and private sectors despite having a relatively lower share of the ill-health burden. The importance of the findings for the design of a universal health system is discussed.

  17. Grote Reber, Radio Astronomy Pioneer, Dies

    Science.gov (United States)

    2002-12-01

    something of a minor tourist attraction, he later recalled. Using electronics he designed and built that pushed the technical capabilities of the era, Reber succeeded in detecting "cosmic static" in 1939. In 1941, Reber produced the first radio map of the sky, based on a series of systematic observations. His radio-astronomy work continued over the next several years. Though not a professional scientist, his research results were published in a number of prestigious technical journals, including Nature, the Astrophysical Journal, the Proceedings of the Institute of Radio Engineers and the Journal of Geophysical Research. Reber also received a number of honors normally reserved for scientists professionally trained in astronomy, including the American Astronomical Society's Henry Norris Russell Lectureship and the Astronomical Society of the Pacific's Bruce Medal in 1962, the National Radio Astronomy Observatory's Jansky Lectureship in 1975, and the Royal Astronomical Society's Jackson-Gwilt Medal in 1983. Reber's original dish antenna now is on display at the National Radio Astronomy Observatory's site in Green Bank, West Virginia, where Reber worked in the late 1950s. All of his scientific papers and records as well as his personal and scientific correspondence are held by the NRAO, and will be exhibited in the observatory's planned new library in Charlottesville, Virginia. Reber's amateur-radio callsign, W9GFZ, is held by the NRAO Amateur Radio Club. This callsign was used on the air for the first time since the 1930s on August 25, 2000, to mark the dedication of the Robert C. Byrd Green Bank Telescope. The National Radio Astronomy Observatory is a facility of the National Science Foundation, operated under cooperative agreement by Associated Universities, Inc.

  18. 26 CFR 1.1081-7 - Sale of stock or securities received upon exchange by members of system group.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 11 2010-04-01 2010-04-01 true Sale of stock or securities received upon.... Orders § 1.1081-7 Sale of stock or securities received upon exchange by members of system group. (a... which are members of the same system group consists of stock or securities issued by the corporation...

  19. A Three-Year Program of Micro- and Nano-System Technology Development for X-Ray Astronomy

    Science.gov (United States)

    Canizares, Claude R.

    1997-01-01

    For many years the work at MIT aimed at the development of new concepts and technologies for space experiments in high-energy astrophysics, but not explicitly supported by flight programs, has been supported. This work has yielded new devices and techniques for X-ray astronomy, primarily low-noise, deep-depletion charge-coupled devices (CCDS) for spectrally-resolved X-ray imaging, and high-performance transmission gratings for high-resolution X-ray spectroscopy. Among the most significant recent achievements have been the development by G. Ricker and associates of the X-ray CCD camera flying on ASCA, and currently in development for AXAF and Astro-E, and the development by C. Canizares and associates of thick, 200 nm-period transmission gratings employing the phenomenon of phase shifting for high-resolution X-ray spectroscopy up to energies of 8- 1 0 keV that is essential for the operation of the AXAF High Energy Transmission Grating Spectrometer (HETGS). Through the current SR&T grant, the latter technology is now being extended successfully to the fabrication of 100 nm-period transmission gratings, which have twice the dispersion of the AXAF gratings. We note that, among other outcomes, the modest investments of past SR&T Grants at MIT resulted in the development of the key technologies for fully one-half of the scientific instrumentation on AXAF. In addition, NASA flight programs that have benefited from previous SR&T support at MIT include the SAS 3 X-ray Observatory, which carried the first rotation modulation collimator, the Focal Plane Crystal Spectrometer (FPCS) on the Einstein Observatory, the CCD cameras on ASCA and planned for Astro-E, the High Energy Transient Experiment (HETE), the Solar EUV Monitor on the Solar and Heliospheric Observatory (SOHO), the Medium Energy Neutral Atom imager (MENA) on the Image for Magnetopause-to-aurora Global Exploration (IMAGE) mission, and the recently-approved Two Wide-Angle Imaging Neutral-atom Spectrometers (TWINS

  20. Global Positioning System (GPS) Receiver Autonomous Integrity Monitoring (RAIM) web service to support Area Navigation (RNAV) flight planning

    Science.gov (United States)

    2008-01-28

    The Volpe Center designed, implemented, and deployed a Global Positioning System (GPS) Receiver Autonomous Integrity Monitoring (RAIM) prediction system in the mid 1990s to support both Air Force and Federal Aviation Administration (FAA) use of TSO C...

  1. Using the Teach Astronomy Website to Enrich Introductory Astronomy Classes

    Science.gov (United States)

    Hardegree-Ullman, K. K.; Impey, C. D.; Patikkal, A.; Austin, C. L.

    2013-04-01

    This year we implemented Teach Astronomy as a free online resource to be used as a teaching tool for non-science major astronomy courses and for a general audience interested in the subject. The comprehensive astronomy content of the website includes: an introductory text book, encyclopedia articles, images, two to three minute topical video clips, podcasts, and news articles. Teach Astronomy utilizes a novel technology to cluster, display, and navigate search results, called a Wikimap. We will present an overview of how Teach Astronomy works and how instructors can use it as an effective teaching tool in the classroom. Additionally, we will gather feedback from science instructors on how to improve the features and functionality of the website, as well as develop new assignment ideas using Teach Astronomy.

  2. Low Complexity Precoder and Receiver Design for Massive MIMO Systems: A Large System Analysis using Random Matrix Theory

    KAUST Repository

    Sifaou, Houssem

    2016-05-01

    Massive MIMO systems are shown to be a promising technology for next generations of wireless communication networks. The realization of the attractive merits promised by massive MIMO systems requires advanced linear precoding and receiving techniques in order to mitigate the interference in downlink and uplink transmissions. This work considers the precoder and receiver design in massive MIMO systems. We first consider the design of the linear precoder and receiver that maximize the minimum signal-to-interference-plus-noise ratio (SINR) subject to a given power constraint. The analysis is carried out under the asymptotic regime in which the number of the BS antennas and that of the users grow large with a bounded ratio. This allows us to leverage tools from random matrix theory in order to approximate the parameters of the optimal linear precoder and receiver by their deterministic approximations. Such a result is of valuable practical interest, as it provides a handier way to implement the optimal precoder and receiver. To reduce further the complexity, we propose to apply the truncated polynomial expansion (TPE) concept on a per-user basis to approximate the inverse of large matrices that appear on the expressions of the optimal linear transceivers. Using tools from random matrix theory, we determine deterministic approximations of the SINR and the transmit power in the asymptotic regime. Then, the optimal per-user weight coe cients that solve the max-min SINR problem are derived. The simulation results show that the proposed precoder and receiver provide very close to optimal performance while reducing signi cantly the computational complexity. As a second part of this work, the TPE technique in a per-user basis is applied to the optimal linear precoding that minimizes the transmit power while satisfying a set of target SINR constraints. Due to the emerging research eld of green cellular networks, such a problem is receiving increasing interest nowadays. Closed

  3. X-ray instrumentation in astronomy

    International Nuclear Information System (INIS)

    Cuhlane, J.L.

    1985-01-01

    This book presents the proceedings of a conference devoted to x-ray instrumentation in astronomy. Special sections are: AXAF X-Ray Optical Systems; Specialized X-Ray Systems; X-Ray Optical Systems I; X-Ray Optical Systems II; Gas Filled X-Ray Detectors II; The NASA Advanced X-Ray Astrophysics Facility; X-Ray and EUV Spectrometers; Microchannel Plates; and Solid State Detectors

  4. X-ray astronomy

    International Nuclear Information System (INIS)

    Giacconi, R.; Setti, G.

    1980-01-01

    This book contains the lectures, and the most important seminars held at the NATO meeting on X-Ray astronomy in Erice, July 1979. The meeting was an opportune forum to discuss the results of the first 8-months of operation of the X-ray satellite, HEAO-2 (Einstein Observatory) which was launched at the end of 1978. Besides surveying these results, the meeting covered extragalactic astronomy, including the relevant observations obtained in other portions of the electromagnetic spectrum (ultra-violet, optical, infrared and radio). The discussion on galactic X-ray sources essentially covered classical binaries, globular clusters and bursters and its significance to extragalactic sources and to high energy astrophysics was borne in mind. (orig.)

  5. Astronomy and astrology

    Science.gov (United States)

    Zarka, Philippe

    2011-06-01

    Astrology meets a large success in our societies, from the private to the political sphere as well as in the media, in spite of the demonstrated inaccuracy of its psychological as well as operational predictions. We analyse here the relations between astrology and astronomy, as well as the criticisms opposed by the latter to the former. We show that most of these criticisms are weak. Much stronger ones emerge from the analysis of the astrological practice compared to the scientific method, leading us to conclude to the non-scientificity of astrology. Then we return to the success of astrology, and from its analysis we propose a renewed (and prophylactic) rôle for astronomy in society.

  6. Infrared Astronomy Satellite

    Science.gov (United States)

    Ferrera, G. A.

    1981-09-01

    In 1982, the Infrared Astronomy Satellite (IRAS) will be launched into a 900-km sun-synchronous (twilight) orbit to perform an unbiased, all-sky survey of the far-infrared spectrum from 8 to 120 microns. Observations telemetered to ground stations will be compiled into an IR astronomy catalog. Attention is given the cryogenically cooled, 60-cm Ritchey-Chretien telescope carried by the satellite, whose primary and secondary mirrors are fabricated from beryllium by means of 'Cryo-Null Figuring'. This technique anticipates the mirror distortions that will result from cryogenic cooling of the telescope and introduces dimensional compensations for them during machining and polishing. Consideration is also given to the interferometric characterization of telescope performance and Cryo/Thermal/Vacuum simulated space environment testing.

  7. 3D Virtual Reality for Teaching Astronomy

    Science.gov (United States)

    Speck, Angela; Ruzhitskaya, L.; Laffey, J.; Ding, N.

    2012-01-01

    We are developing 3D virtual learning environments (VLEs) as learning materials for an undergraduate astronomy course, in which will utilize advances both in technologies available and in our understanding of the social nature of learning. These learning materials will be used to test whether such VLEs can indeed augment science learning so that it is more engaging, active, visual and effective. Our project focuses on the challenges and requirements of introductory college astronomy classes. Here we present our virtual world of the Jupiter system and how we plan to implement it to allow students to learn course material - physical laws and concepts in astronomy - while engaging them into exploration of the Jupiter's system, encouraging their imagination, curiosity, and motivation. The VLE can allow students to work individually or collaboratively. The 3D world also provides an opportunity for research in astronomy education to investigate impact of social interaction, gaming features, and use of manipulatives offered by a learning tool on students’ motivation and learning outcomes. Use of this VLE is also a valuable source for exploration of how the learners’ spatial awareness can be enhanced by working in 3D environment. We will present the Jupiter-system environment along with a preliminary study of the efficacy and usability of our Jupiter 3D VLE.

  8. Archaeology and astronomy

    Science.gov (United States)

    2009-10-01

    MEETING REPORT The interaction between archaeology and astronomy has a long, tangled and not entirely creditable history, marred by misunderstandings on both sides. But statistics and cultural awareness are bringing a better picture of how and why lasting monuments such as Stonehenge were built. Sue Bowler reports on a joint meeting of the Royal Astronomical Society and the Prehistoric Society, held at Jodrell Bank on 17 July 2009.

  9. Gravitational Wave Astronomy

    CERN Multimedia

    CERN. Geneva

    2006-01-01

    Gravitational wave astronomy is expected to become an observational field within the next decade. First direct detection of gravitational waves is possible with existing terrestrial-based detectors, and highly probable with proposed upgrades. In this three-part lecture series, we give an overview of the field, including material on gravitional wave sources, detection methods, some details of interferometric detectors, data analysis methods, and current results from observational data-taking runs of the LIGO and GEO projects.

  10. Astronomy on a Landfill

    Science.gov (United States)

    Venner, Laura

    2008-09-01

    Engaging "K-to-Gray” audiences (children, families, and older adults) in astronomical activities is one of the main goals of the NJMC Center for Environmental and Scientific Education and the William D. McDowell Observatory located in Lyndhurst, NJ. Perched atop a closed and reclaimed municipal solid waste landfill, our new LEED - certified building (certification pending) and William D. McDowell observatory will assist in bringing the goals of IYA 2009 to the approximately 25,000 students and 15,000 adults that visit our site from the NY/NJ region each year. Diversifying our traditional environmental science offerings, we have incorporated astronomy into our repertoire with "The Sun Through Time” module, which includes storytelling, cultural astronomy, telescope anatomy, and other activities that are based on the electromagnetic spectrum and our current knowledge of the sun. These lessons have also been modified to bring astronomy to underserved communities, specifically those individuals that have dexterity or cognitive ability differences. The program is conducted in a classroom setting and is designed to meet New Jersey Core Curriculum Content Standards. With the installation of our new 20” telescope, students and amateur astronomers will be given the opportunity to perform rudimentary research. In addition, a program is in development that will allow individuals to measure local sky brightness and understand the effects of light pollution on astronomical viewing. Teaching astronomy in an urban setting presents many challenges. All individuals, regardless of ability level or location, should be given the opportunity to be exposed to the wonders of the universe and the MEC/CESE has been successful in providing those opportunities.

  11. Nonlinear Multiuser Receiver for Optimized Chaos-Based DS-CDMA Systems

    Directory of Open Access Journals (Sweden)

    S. Shaerbaf

    2011-09-01

    Full Text Available Chaos based communications have drawn increasing attention over the past years. Chaotic signals are derived from non-linear dynamic systems. They are aperiodic, broadband and deterministic signals that appear random in the time domain. Because of these properties, chaotic signals have been proposed to generate spreading sequences for wide-band secure communication recently. Like conventional DS-CDMA systems, chaos-based CDMA systems suffer from multi-user interference (MUI due to other users transmitting in the cell. In this paper, we propose a novel method based on radial basis function (RBF for both blind and non-blind multiuser detection in chaos-based DS-CDMA systems. We also propose a new method for optimizing generation of binary chaotic sequences using Genetic Algorithm. Simulation results show that our proposed nonlinear receiver with optimized chaotic sequences outperforms in comparison to other conventional detectors such as a single-user detector, decorrelating detector and minimum mean square error detector, particularly for under-loaded CDMA condition, which the number of active users is less than processing gain.

  12. The New Digital-Receiver-Based System for Antiproton Beam Diagnostics

    CERN Document Server

    Angoletta, Maria Elena; Ludwig, M; Marqversen, O; Pedersen, F

    2001-01-01

    An innovative system to measure antiproton beam intensity, momentum spread and mean momentum in CERN's Antiproton Decelerator (AD) is described. This system is based on a state-of-the-art Digital Receiver (DRX) board, consisting of 8 Digital Down-Converter (DDC) chips and one Digital Signal Processor (DSP). An ultra-low-noise, wide-band AC beam transformer (0.2 MHz - 30 MHz) is used to measure AC beam current modulation. For bunched beams, the intensity is obtained by measuring the amplitude of the fundamental and second RF Fourier components. On the magnetic plateaus the beam is debunched for stochastic or electron cooling and longitudinal beam properties (intensity, momentum spread and mean momentum) are measured by FFT-based spectral analysis of Schottky signals. The system thus provides real time information characterising the machine performance; it has been used for troubleshooting and to fine-tune the AD, thus achieving further improved performances. This system has been operating since May 2000 and ty...

  13. Astronomy in the streets

    Science.gov (United States)

    Kebe, Fatoumata

    2015-08-01

    The Ephemerides Association was founded last year by a PhD student in Astronomy. The association is devoted to the promotion and advancement of knowledge of the universe through research and education.The main activities of the association are scientific meetings, the planning and realization of scientific projects, the support of the scientific activities of its members, and the dissemination of related information among members and other interested persons.The association targets the disadvantaged zones of the Paris suburbs.The main issue was how to bring astronomy in those places. In the suburbs, since most of the youth are poor, most leisure activities like cinema are out of your reach. Thus, mostly of them will play football or basketball outside.We decided to go to meet young people who find themselves together in the evening. We prepare the telescope as well as the fasicules to start the observation of the planets. The discussion finally lead to their career plans and aspirations. Astronomy has become a tool to address societal issues. We present our results after one year of activity.

  14. Receiver design for SPAD-based VLC systems under Poisson-Gaussian mixed noise model.

    Science.gov (United States)

    Mao, Tianqi; Wang, Zhaocheng; Wang, Qi

    2017-01-23

    Single-photon avalanche diode (SPAD) is a promising photosensor because of its high sensitivity to optical signals in weak illuminance environment. Recently, it has drawn much attention from researchers in visible light communications (VLC). However, existing literature only deals with the simplified channel model, which only considers the effects of Poisson noise introduced by SPAD, but neglects other noise sources. Specifically, when an analog SPAD detector is applied, there exists Gaussian thermal noise generated by the transimpedance amplifier (TIA) and the digital-to-analog converter (D/A). Therefore, in this paper, we propose an SPAD-based VLC system with pulse-amplitude-modulation (PAM) under Poisson-Gaussian mixed noise model, where Gaussian-distributed thermal noise at the receiver is also investigated. The closed-form conditional likelihood of received signals is derived using the Laplace transform and the saddle-point approximation method, and the corresponding quasi-maximum-likelihood (quasi-ML) detector is proposed. Furthermore, the Poisson-Gaussian-distributed signals are converted to Gaussian variables with the aid of the generalized Anscombe transform (GAT), leading to an equivalent additive white Gaussian noise (AWGN) channel, and a hard-decision-based detector is invoked. Simulation results demonstrate that, the proposed GAT-based detector can reduce the computational complexity with marginal performance loss compared with the proposed quasi-ML detector, and both detectors are capable of accurately demodulating the SPAD-based PAM signals.

  15. Method of steering the gain of a multiple antenna global positioning system receiver

    Science.gov (United States)

    Evans, Alan G.; Hermann, Bruce R.

    1992-06-01

    A method for steering the gain of a multiple antenna Global Positioning System (GPS) receiver toward a plurality of a GPS satellites simultaneously is provided. The GPS signals of a known wavelength are processed digitally for a particular instant in time. A range difference or propagation delay between each antenna for GPS signals received from each satellite is first resolved. The range difference consists of a fractional wavelength difference and an integer wavelength difference. The fractional wavelength difference is determined by each antenna's tracking loop. The integer wavelength difference is based upon the known wavelength and separation between each antenna with respect to each satellite position. The range difference is then used to digitally delay the GPS signals at each antenna with respect to a reference antenna. The signal at the reference antenna is then summed with the digitally delayed signals to generate a composite antenna gain. The method searches for the correct number of integer wavelengths to maximize the composite gain. The range differences are also used to determine the attitude of the array.

  16. Received Signal Strength Database Interpolation by Kriging for a Wi-Fi Indoor Positioning System.

    Science.gov (United States)

    Jan, Shau-Shiun; Yeh, Shuo-Ju; Liu, Ya-Wen

    2015-08-28

    The main approach for a Wi-Fi indoor positioning system is based on the received signal strength (RSS) measurements, and the fingerprinting method is utilized to determine the user position by matching the RSS values with the pre-surveyed RSS database. To build a RSS fingerprint database is essential for an RSS based indoor positioning system, and building such a RSS fingerprint database requires lots of time and effort. As the range of the indoor environment becomes larger, labor is increased. To provide better indoor positioning services and to reduce the labor required for the establishment of the positioning system at the same time, an indoor positioning system with an appropriate spatial interpolation method is needed. In addition, the advantage of the RSS approach is that the signal strength decays as the transmission distance increases, and this signal propagation characteristic is applied to an interpolated database with the Kriging algorithm in this paper. Using the distribution of reference points (RPs) at measured points, the signal propagation model of the Wi-Fi access point (AP) in the building can be built and expressed as a function. The function, as the spatial structure of the environment, can create the RSS database quickly in different indoor environments. Thus, in this paper, a Wi-Fi indoor positioning system based on the Kriging fingerprinting method is developed. As shown in the experiment results, with a 72.2% probability, the error of the extended RSS database with Kriging is less than 3 dBm compared to the surveyed RSS database. Importantly, the positioning error of the developed Wi-Fi indoor positioning system with Kriging is reduced by 17.9% in average than that without Kriging.

  17. Conceptual design of advanced central receiver power systems sodium-cooled receiver concept. Volume 2, Book 1. Commercial plant conceptual design. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1979-03-01

    The conceptual design of the 100-MW solar tower focus commercial power plant is described in detail. Sodium is pumped up to the top of a tall tower where the receiver is located. The sodium is heated in the receiver and then flows down the tower, through a pressure reducing device, and thence into a large, hot storage tank which is located at ground level and whose size is made to meet a specific thermal energy storage capacity requirement. From this tank, the sodium is pumped by a separate pump, through a system of sodium-to-water steam generators. The steam generator system consists of a separate superheater and reheater operating in parallel and an evaporator unit operating in series with the other two units. The sodium flowing from the evaporator unit is piped to a cold storage tank. From the cold storage tank, sodium is then pumped up to the tip of the tower to complete the cycle. The steam generated in the steam generators is fed to a conventional off-the-shelf, high-efficiency turbine. The steam loop operates in a conventional rankine cycle with the steam generators serving the same purpose as a conventional boiler and water being fed to the evaporator with conventional feedwater pumps. The pressure reducing device (a standard drag valve, for example) serves to mitigate the pressure caused by the static head of sodium and thus allows the large tanks to operate at ambient pressure conditions. (WHK)

  18. Gas spectroscopy system with 245 GHz transmitter and receiver in SiGe BiCMOS

    Science.gov (United States)

    Schmalz, Klaus; Rothbart, Nick; Borngräber, Johannes; Yilmaz, Selahattin Berk; Kissinger, Dietmar; Hübers, Heinz-Wilhelm

    2017-02-01

    The implementation of an integrated mm-wave transmitter (TX) and receiver (RX) in SiGe BiCMOS or CMOS technology offers a path towards a compact and low-cost system for gas spectroscopy. Previously, we have demonstrated TXs and RXs for spectroscopy at 238 -252 GHz and 495 - 497 GHz using external phase-locked loops (PLLs) with signal generators for the reference frequency ramps. Here, we present a more compact system by using two external fractional-N PLLs allowing frequency ramps for the TX and RX, and for TX with superimposed frequency shift keying (FSK) or reference frequency modulation realized by a direct digital synthesizer (DDS) or an arbitrary waveform generator. The 1.9 m folded gas absorption cell, the vacuum pumps, as well as the TX and RX are placed on a portable breadboard with dimensions of 75 cm x 45 cm. The system performance is evaluated by high-resolution absorption spectra of gaseous methanol at 13 Pa for 241 - 242 GHz. The 2f (second harmonic) content of the absorption spectrum of the methanol was obtained by detecting the IF power of RX using a diode power sensor connected to a lock-in amplifier. The reference frequency modulation reveals a higher SNR (signal-noise-ratio) of 98 within 32 s acquisition compared to 66 for FSK. The setup allows for jumping to preselected frequency regions according to the spectral signature thus reducing the acquisition time by up to one order of magnitude.

  19. Rapid stress system drives chemical transfer of fear from sender to receiver.

    Directory of Open Access Journals (Sweden)

    Jasper H B de Groot

    Full Text Available Humans can register another person's fear not only with their eyes and ears, but also with their nose. Previous research has demonstrated that exposure to body odors from fearful individuals elicited implicit fear in others. The odor of fearful individuals appears to have a distinctive signature that can be produced relatively rapidly, driven by a physiological mechanism that has remained unexplored in earlier research. The apocrine sweat glands in the armpit that are responsible for chemosignal production contain receptors for adrenalin. We therefore expected that the release of adrenalin through activation of the rapid stress response system (i.e., the sympathetic-adrenal medullary system is what drives the release of fear sweat, as opposed to activation of the slower stress response system (i.e., hypothalamus-pituitary-adrenal axis. To test this assumption, sweat was sampled while eight participants prepared for a speech. Participants had higher heart rates and produced more armpit sweat in the fast stress condition, compared to baseline and the slow stress condition. Importantly, exposure to sweat from participants in the fast stress condition induced in receivers (N = 31 a simulacrum of the state of the sender, evidenced by the emergence of a fearful facial expression (facial electromyography and vigilant behavior (i.e., faster classification of emotional facial expressions.

  20. Operator decision support system for integrated wastewater management including wastewater treatment plants and receiving water bodies.

    Science.gov (United States)

    Kim, Minsoo; Kim, Yejin; Kim, Hyosoo; Piao, Wenhua; Kim, Changwon

    2016-06-01

    An operator decision support system (ODSS) is proposed to support operators of wastewater treatment plants (WWTPs) in making appropriate decisions. This system accounts for water quality (WQ) variations in WWTP influent and effluent and in the receiving water body (RWB). The proposed system is comprised of two diagnosis modules, three prediction modules, and a scenario-based supporting module (SSM). In the diagnosis modules, the WQs of the influent and effluent WWTP and of the RWB are assessed via multivariate analysis. Three prediction modules based on the k-nearest neighbors (k-NN) method, activated sludge model no. 2d (ASM2d) model, and QUAL2E model are used to forecast WQs for 3 days in advance. To compare various operating alternatives, SSM is applied to test various predetermined operating conditions in terms of overall oxygen transfer coefficient (Kla), waste sludge flow rate (Qw), return sludge flow rate (Qr), and internal recycle flow rate (Qir). In the case of unacceptable total phosphorus (TP), SSM provides appropriate information for the chemical treatment. The constructed ODSS was tested using data collected from Geumho River, which was the RWB, and S WWTP in Daegu City, South Korea. The results demonstrate the capability of the proposed ODSS to provide WWTP operators with more objective qualitative and quantitative assessments of WWTP and RWB WQs. Moreover, the current study shows that ODSS, using data collected from the study area, can be used to identify operational alternatives through SSM at an integrated urban wastewater management level.

  1. Intelligent Security IT System for Detecting Intruders Based on Received Signal Strength Indicators

    Directory of Open Access Journals (Sweden)

    Yunsick Sung

    2016-10-01

    Full Text Available Given that entropy-based IT technology has been applied in homes, office buildings and elsewhere for IT security systems, diverse kinds of intelligent services are currently provided. In particular, IT security systems have become more robust and varied. However, access control systems still depend on tags held by building entrants. Since tags can be obtained by intruders, an approach to counter the disadvantages of tags is required. For example, it is possible to track the movement of tags in intelligent buildings in order to detect intruders. Therefore, each tag owner can be judged by analyzing the movements of their tags. This paper proposes a security approach based on the received signal strength indicators (RSSIs of beacon-based tags to detect intruders. The normal RSSI patterns of moving entrants are obtained and analyzed. Intruders can be detected when abnormal RSSIs are measured in comparison to normal RSSI patterns. In the experiments, one normal and one abnormal scenario are defined for collecting the RSSIs of a Bluetooth-based beacon in order to validate the proposed method. When the RSSIs of both scenarios are compared to pre-collected RSSIs, the RSSIs of the abnormal scenario are about 61% more different compared to the RSSIs of the normal scenario. Therefore, intruders in buildings can be detected by considering RSSI differences.

  2. Mac OS X for Astronomy

    Science.gov (United States)

    Pierfederici, F.; Pirzkal, N.; Hook, R. N.

    Mac OS X is the new Unix based version of the Macintosh operating system. It combines a high performance DisplayPDF user interface with a standard BSD UNIX subsystem and provides users with simultaneous access to a broad range of applications which were not previously available on a single system such as Microsoft Office and Adobe Photoshop, as well as legacy X11-based scientific tools and packages like IRAF, SuperMongo, MIDAS, etc. The combination of a modern GUI layered on top of a familiar UNIX environment paves the way for new, more flexible and powerful astronomical tools to be developed while assuring compatibility with already existing, older programs. In this paper, we outline the strengths of the Mac OS X platform in a scientific environment, astronomy in particular, and point to the numerous astronomical software packages available for this platform; most notably the Scisoft collection which we have compiled.

  3. Episodes from the Early History of Astronomy

    Science.gov (United States)

    Aaboe, Asger

    The author does not attempt to give a general survey of early astronomy; rather, he chooses to present a few "episodes" and treats them in detail. However, first he provides the necessary astronomical background in his descriptive account of what you can see when you look at the sky with the naked eye, unblinkered by received knowledge, but with curiosity and wit. Chapter 1 deals with the arithmetical astronomy of ancient Mesopotamia where astronomy first was made an exact science. Next are treated Greek geometrical models for planetary motion, culminating in Ptolemy's equant models in his Almagest. Ptolemy does not assign them absolute size in this work, but, as is shown here, if we scale the models properly, they will yield good values, not only of the directions to the planets, but of the distances to them, as well. Thus one can immediately find the dimensions of the Copernican System from parameters in the Almagest - we have evidence that Copernicus did just that. Further, Islamic astronomers' modifications of Ptolemy's models by devices using only uniform circular motion are discussed, as are Copernicus's adoption of some of them. finally, it is made precise which bothersome problem was resolved by the heliocentric hypothesis, as it was by the Tychonic arrangement. Next, the Ptolemaic System, the first cosmological scheme to incorporate quantitative models, is described as Ptolemy himself did it in a recenlty recovered passage from his Planetary Hypotheses. Here he does assign absolute size to his models in order to fit them into the snugly nested spherical shells that made up his universe. This much maligned system was, in fact, a harmonious construct that remained the basis for how educated people thought of their world for a millennium and a half. Finally, after a brief review of the geometry of the ellipse, the author gives an elementary derivation of Kepler's equation, and shows how Kepler solved it, and further proves that a planet moves very nearly

  4. Journal of Astrophysics and Astronomy | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    2016-01-27

    Jan 27, 2016 ... The integration of components is being done. The integrated performance of the system on a tracking mount and its control software is being tested. ... and Astronomy has moved to Continuous Article Publishing (CAP) mode.

  5. Transmission of Babylonian Astronomy to Other Cultures

    Science.gov (United States)

    Jones, Alexander

    Babylonian astronomy and astrology were extensively transmitted to other civilizations in the second and first millennia BC. Greek astronomy in particular was largely shaped by knowledge of Babylonian observations and mathematical astronomy.

  6. Determination of global positioning system (GPS) receiver clock errors: impact on positioning accuracy

    International Nuclear Information System (INIS)

    Yeh, Ta-Kang; Hwang, Cheinway; Xu, Guochang; Wang, Chuan-Sheng; Lee, Chien-Chih

    2009-01-01

    Enhancing the positioning precision is the primary pursuit of global positioning system (GPS) users. To achieve this goal, most studies have focused on the relationship between GPS receiver clock errors and GPS positioning precision. This study utilizes undifferentiated phase data to calculate GPS clock errors and to compare with the frequency of cesium clock directly, to verify estimated clock errors by the method used in this paper. The frequency stability calculated from this paper (the indirect method) and measured from the National Standard Time and Frequency Laboratory (NSTFL) of Taiwan (the direct method) match to 1.5 × 10 −12 (the value from this study was smaller than that from NSTFL), suggesting that the proposed technique has reached a certain level of quality. The built-in quartz clocks in the GPS receivers yield relative frequency offsets that are 3–4 orders higher than those of rubidium clocks. The frequency stability of the quartz clocks is on average two orders worse than that of the rubidium clock. Using the rubidium clock instead of the quartz clock, the horizontal and vertical positioning accuracies were improved by 26–78% (0.6–3.6 mm) and 20–34% (1.3–3.0 mm), respectively, for a short baseline. These improvements are 7–25% (0.3–1.7 mm) and 11% (1.7 mm) for a long baseline. Our experiments show that the frequency stability of the clock, rather than relative frequency offset, is the governing factor of positioning accuracy

  7. All-optical OFDM system using a wavelength selective switch based transmitter and a spectral magnification based receiver

    DEFF Research Database (Denmark)

    Guan, Pengyu; Lefrancois, S.; Lillieholm, Mads

    2014-01-01

    We demonstrate an AO-OFDM system with a WSS-based transmitter and time-lens based receiver for spectral magnification, achieving BER~10-9 for a 28×10 Gbit/s DPSK AO-OFDM signal. Furthermore, the receiver performance for DPSK and DQPSK is investigated using Monte Carlo simulations....

  8. Acceptance test report, 241-SY-101 Flexible Receiver System, Phase 1 testing

    International Nuclear Information System (INIS)

    Ritter, G.A.

    1995-01-01

    This document summarizes the results of the Phase 1 acceptance test of the 241-SY-101 Flexible Receiver System (FRS). This acceptance test consisted of a pressure-decay/leak test of the containment bag to verify that the seams along the length of the bag had been adequately sealed. The sealing integrity of the FRS must be verified to ensure that the release of waste and aerosols will be minimized during the removal of the test mixer pump from Tank 241-SY-101. The FRS is one of six major components of the Equipment Removal System, which has been designed to retrieve, transport, and store the mixer pump. This acceptance test was performed at Lancs Industries in Kirkland, Washington on January 17, 1995. The bag temperature-compensated pressure loss of 575 Pa was below the acceptance criteria of 625 Pa and the test results were therefore found to be acceptable. The bag manufacturer estimates that 80--90% of the pressure loss is attributed to leakage around the bag inflation valve where the pressure gage was connected. A leak detector was applied over the entire bag during the pre-tests and no leakage was found. Furthermore, the leak rate corresponding to this pressure loss is very small when compared to the acceptable leak rate of the completely assembled FRS. The sealing integrity of the assembled FRS is verified in Phase 3 testing

  9. New readout and data-acquisition system in an electron-tracking Compton camera for MeV gamma-ray astronomy (SMILE-II)

    Energy Technology Data Exchange (ETDEWEB)

    Mizumoto, T., E-mail: mizumoto@cr.scphys.kyoto-u.ac.jp [Department of Physics, Kyoto University, 606-8502 Kyoto (Japan); Matsuoka, Y. [Department of Physics, Kyoto University, 606-8502 Kyoto (Japan); Mizumura, Y. [Unit of Synergetic Studies for Space, Kyoto University, 606-8502 Kyoto (Japan); Department of Physics, Kyoto University, 606-8502 Kyoto (Japan); Tanimori, T. [Department of Physics, Kyoto University, 606-8502 Kyoto (Japan); Unit of Synergetic Studies for Space, Kyoto University, 606-8502 Kyoto (Japan); Kubo, H.; Takada, A.; Iwaki, S.; Sawano, T.; Nakamura, K.; Komura, S.; Nakamura, S.; Kishimoto, T.; Oda, M.; Miyamoto, S.; Takemura, T.; Parker, J.D.; Tomono, D.; Sonoda, S. [Department of Physics, Kyoto University, 606-8502 Kyoto (Japan); Miuchi, K. [Department of Physics, Kobe University, 658-8501 Kobe (Japan); Kurosawa, S. [Institute for Materials Research, Tohoku University, 980-8577 Sendai (Japan)

    2015-11-11

    For MeV gamma-ray astronomy, we have developed an electron-tracking Compton camera (ETCC) as a MeV gamma-ray telescope capable of rejecting the radiation background and attaining the high sensitivity of near 1 mCrab in space. Our ETCC comprises a gaseous time-projection chamber (TPC) with a micro pattern gas detector for tracking recoil electrons and a position-sensitive scintillation camera for detecting scattered gamma rays. After the success of a first balloon experiment in 2006 with a small ETCC (using a 10×10×15 cm{sup 3} TPC) for measuring diffuse cosmic and atmospheric sub-MeV gamma rays (Sub-MeV gamma-ray Imaging Loaded-on-balloon Experiment I; SMILE-I), a (30 cm){sup 3} medium-sized ETCC was developed to measure MeV gamma-ray spectra from celestial sources, such as the Crab Nebula, with single-day balloon flights (SMILE-II). To achieve this goal, a 100-times-larger detection area compared with that of SMILE-I is required without changing the weight or power consumption of the detector system. In addition, the event rate is also expected to dramatically increase during observation. Here, we describe both the concept and the performance of the new data-acquisition system with this (30 cm){sup 3} ETCC to manage 100 times more data while satisfying the severe restrictions regarding the weight and power consumption imposed by a balloon-borne observation. In particular, to improve the detection efficiency of the fine tracks in the TPC from ~10% to ~100%, we introduce a new data-handling algorithm in the TPC. Therefore, for efficient management of such large amounts of data, we developed a data-acquisition system with parallel data flow.

  10. Astronomy across cultures the history of non-Western astronomy

    CERN Document Server

    Xiaochun, Sun

    2000-01-01

    Astronomy Across Cultures: A History of Non-Western Astronomy consists of essays dealing with the astronomical knowledge and beliefs of cultures outside the United States and Europe. In addition to articles surveying Islamic, Chinese, Native American, Aboriginal Australian, Polynesian, Egyptian and Tibetan astronomy, among others, the book includes essays on Sky Tales and Why We Tell Them and Astronomy and Prehistory, and Astronomy and Astrology. The essays address the connections between science and culture and relate astronomical practices to the cultures which produced them. Each essay is well illustrated and contains an extensive bibliography. Because the geographic range is global, the book fills a gap in both the history of science and in cultural studies. It should find a place on the bookshelves of advanced undergraduate students, graduate students, and scholars, as well as in libraries serving those groups.

  11. Dyslexia and Astronomy

    Science.gov (United States)

    Schneps, Matthew H.; Greenhill, L. J.; Rose, L. T.

    2007-12-01

    Dyslexia is a hereditary neurological disability that impairs reading. It is believed that anywhere from 5% to 20% of all people in the US may have dyslexia to a greater or lesser degree. Though dyslexia is common, it is a "silent disability" in the sense that it is not easy to tell which individuals suffer from dyslexia and which do not. There is a substantial body of evidence to suggest that people with dyslexia tend to do well in science. For example, Baruj Benacerraf, a Nobel laureate in medicine, is among those whose impairments have been documented and studied. Given that dyslexia was not diagnosed in schools prior to the late 1970's, many established science researchers may have dyslexia and be unaware of their impairment. Therefore, it would not be surprising to find that substantial numbers of scientists working in the fields of astronomy and astrophysics have dyslexia, and yet be unaware of the effects this disability has had on their research. A recently proposed theory by the authors suggests that there may be specific neurological reasons why those with dyslexia may be predisposed to science, and predicts that dyslexia may be associated with enhanced abilities for certain types of visual processing, with special implications for image processing. Our study, funded by the NSF, investigates this hypothesis in the context of astronomy and astrophysics. We expect this work will uncover and document challenges faced by scientists with dyslexia, but perhaps more importantly, lead to an understanding of the strengths these scientists bring to research. The program will serve as a clearing-house of information for scientists and students with dyslexia, and begin to provide mentoring for young people with dyslexia interested in astronomy. Scientists who have reason to believe they may have dyslexia are encouraged to contact the authors.

  12. Gravitational-Wave Astronomy

    Science.gov (United States)

    Kelly, Bernard J.

    2010-01-01

    Einstein's General Theory of Relativity is our best classical description of gravity, and informs modern astronomy and astrophysics at all scales: stellar, galactic, and cosmological. Among its surprising predictions is the existence of gravitational waves -- ripples in space-time that carry energy and momentum away from strongly interacting gravitating sources. In my talk, I will give an overview of the properties of this radiation, recent breakthroughs in computational physics allowing us to calculate the waveforms from galactic mergers, and the prospect of direct observation with interferometric detectors such as LIGO and LISA.

  13. Islamic Mathematical Astronomy

    Science.gov (United States)

    Montelle, Clemency

    A short survey on Islamic mathematical astronomy practiced during the period running from the eight century until the fifteenth is presented. Various pertinent themes, such as the translation of foreign scientific works and their impact on the tradition; the introduction, assimilation, and critique of the Ptolemaic model; and the role of observations, will be covered. In addition, the zīj, the dominant format for astronomical works, will be briefly explained as well as the legacy of the Islamic tradition of astral sciences to other cultures.

  14. X-ray astronomy

    International Nuclear Information System (INIS)

    Narayanan, M.S.

    1976-01-01

    The deployment of detectors outside the deleterious effects of the atmosphere by sending them in space vehicles, has been explained. This has thrown open the entire spectrum of the electromagnetic and particle radiation to direct observations, thus enlarging the vistas of the field of astronomy and astrophysics. The discovery of strong emitters of X-rays such as SCO X-1, NorX-2, transient sources such as Cen X-2, Cen X-4, Cen X-1, Supernova remnants Tan X-1, etc., are reported. The background of the X-ray spectrum as measured during two rocket flights over Thumba, India is presented. (K.B.)

  15. Open Astronomy Catalogs API

    Science.gov (United States)

    Guillochon, James; Cowperthwaite, Philip S.

    2018-05-01

    We announce the public release of the application program interface (API) for the Open Astronomy Catalogs (OACs), the OACAPI. The OACs serve near-complete collections of supernova, tidal disruption, kilonova, and fast stars data (including photometry, spectra, radio, and X-ray observations) via a user-friendly web interface that displays the data interactively and offers full data downloads. The OACAPI, by contrast, enables users to specifically download particular pieces of the OAC dataset via a flexible programmatic syntax, either via URL GET requests, or via a module within the astroquery Python package.

  16. Quantitative Activities for Introductory Astronomy

    Science.gov (United States)

    Keohane, Jonathan W.; Bartlett, J. L.; Foy, J. P.

    2010-01-01

    We present a collection of short lecture-tutorial (or homework) activities, designed to be both quantitative and accessible to the introductory astronomy student. Each of these involves interpreting some real data, solving a problem using ratios and proportionalities, and making a conclusion based on the calculation. Selected titles include: "The Mass of Neptune” "The Temperature on Titan” "Rocks in the Early Solar System” "Comets Hitting Planets” "Ages of Meteorites” "How Flat are Saturn's Rings?” "Tides of the Sun and Moon on the Earth” "The Gliese 581 Solar System"; "Buckets in the Rain” "How Hot, Bright and Big is Betelgeuse?” "Bombs and the Sun” "What Forms Stars?” "Lifetimes of Cars and Stars” "The Mass of the Milky” "How Old is the Universe?” "Is The Universe Speeding up or Slowing Down?"

  17. Academic Training: Astronomy from Space

    CERN Multimedia

    Françoise Benz

    2005-01-01

    2004-2005 ACADEMIC TRAINING PROGRAMME LECTURE SERIES 14, 15, 16, 18 March from 11.00 to 12.00 hrs - Main Auditorium, bldg. 500 Astronomy from Space by T. Courvoisier / Observatoire de Genève In the very wide field of High Energy astrophysics we will select a number of topics that range from the source of radiative energy in the deep potential well around Schwarzschild and Kerr black holes and the basics of accretion disks around compact objects to the description and (where possible) the understanding of binary systems including a compact object (neutron star or black hole), of Active Galactic Nuclei and of gamma ray bursts. The approach that is chosen aims at giving an understanding of the most important phenomenologies encountered in high energy astrophysics rather than a detailed knowledge of one specific topic. ENSEIGNEMENT ACADEMIQUE ACADEMIC TRAINING Françoise Benz 73127 academic.training@cern.ch

  18. ACDA Thirty Years of Popularization of Astronomy in Colombia

    Science.gov (United States)

    Ocampo, W.; Higuera-G., Mario A.

    2017-07-01

    The Colombian Association of Astronomical Studies (ACDA) is a Non Profit Organization with thirty years of permanent efforts for the popularization of astronomy and related sciences in Colombia. ACDA put together amateur and profesional astronomers, as well as interested people. We surely had left a footprint on uncountable number of attending people to our activities, members and former members, and have supported the process of building a new society, with more awareness on the importance of science. We devote our efforts to our members and general people, to keep them motivated, support them and follow each member own interests in order to expand and spread their knowledge. In order to achieve our goals we have develop several strategies as: acquire of didactic material and optical instruments, video projections and discussion, astronomical observations, visits to observatories and planetariums, attending conferences and events, and mainly a weekly Saturday morning talk at the Bogotá Planetarium. ACDA has had different study teams on several fields including: Planetary Systems, Astrobiology, Space Exploration, Cosmology, History of Astronomy and Radioastronomy. ACDA has a national brandname on Astronomy due to seriousness and quality of its projects. A good list of members have become profesional astronomers. From our experience we can say: astronomy is a fertile field to teach science, in general there is an absence of astronomy culture in the public, our best communication experience are astronomical observations, explained astronomy movies and colloquiums, our best public are kids and aged people and finally, social networks gave dynamics to our astronomy spreading initiative.

  19. Astronomie spatiale infrarouge, aujourd’hui et demain = Infrared space astronomy, today and tomorrow

    CERN Document Server

    Lequeux, J; David, F

    2000-01-01

    This book brings together the lectures given at the Les Houches summer school "Infrared space astronomy, today and tomorrow". It gives a wide overview of infrared astronomy, a wavelength domain crucial for studies of the solar system, stars at the beginning and end of their lives, interstellar matter and galaxies at all distances. Recent developments in observational techniques have been tremendous. The first contributions give an introduction to the basic physical processes and methods of detection and data processing. They are followed by a series of lectures dealing with the wide variety of astronomical objects that can be seen in the infrared.

  20. Science and Mathematics in Astronomy

    Science.gov (United States)

    Woolack, Edward

    2009-01-01

    A brief historical introduction to the development of observational astronomy will be presented. The close historical relationship between the successful application of mathematical concepts and advances in astronomy will be presented. A variety of simple physical demonstrations, hands-on group activities, and puzzles will be used to understand how the properties of light can be used to understand the contents of our universe.

  1. An Optical Receiver Post Processing System for the Integrated Radio and Optical Communications Software Defined Radio Test Bed

    Science.gov (United States)

    Nappier, Jennifer M.; Tokars, Roger P.; Wroblewski, Adam C.

    2016-01-01

    The Integrated Radio and Optical Communications (iROC) project at the National Aeronautics and Space Administrations (NASA) Glenn Research Center is investigating the feasibility of a hybrid radio frequency (RF) and optical communication system for future deep space missions. As a part of this investigation, a test bed for a radio frequency (RF) and optical software defined radio (SDR) has been built. Receivers and modems for the NASA deep space optical waveform are not commercially available so a custom ground optical receiver system has been built. This paper documents the ground optical receiver, which is used in order to test the RF and optical SDR in a free space optical communications link.

  2. An Optical Receiver Post-Processing System for the Integrated Radio and Optical Communications Software Defined Radio Test Bed

    Science.gov (United States)

    Nappier, Jennifer M.; Tokars, Roger P.; Wroblewski, Adam C.

    2016-01-01

    The Integrated Radio and Optical Communications (iROC) project at the National Aeronautics and Space Administration's (NASA) Glenn Research Center is investigating the feasibility of a hybrid radio frequency (RF) and optical communication system for future deep space missions. As a part of this investigation, a test bed for a radio frequency (RF) and optical software defined radio (SDR) has been built. Receivers and modems for the NASA deep space optical waveform are not commercially available so a custom ground optical receiver system has been built. This paper documents the ground optical receiver, which is used in order to test the RF and optical SDR in a free space optical communications link.

  3. PCI Based Read-out Receiver Card in the ALICE DAQ System

    CERN Document Server

    Carena, W; Dénes, E; Divià, R; Schossmaier, K; Soós, C; Sulyán, J; Vascotto, Alessandro; Van de Vyvre, P

    2001-01-01

    The Detector Data Link (DDL) is the high-speed optical link for the ALICE experiment. This link shall transfer the data coming from the detectors at 100 MB/s rate. The main components of the link have been developed: the destination Interface Unit (DIU), the Source Interface Unit (SIU) and the Read-out Receiver Card (RORC). The first RORC version is based on the VME bus. The performance tests show that the maximum VME bandwidth could be reached. Meanwhile the PCI bus became very popular and is used in many platforms. The development of a PCI-based version has been started. The document describes the prototype version in three sections. An overview explains the main purpose of the card: to provide an interface between the DDL and the PCI bus. Acting as a 32bit/33MHz PCI master the card is able to write or read directly to or from the system memory from or to the DDL, respectively. Beside these functions the card can also be used as an autonomous data generator. The card has been designed to be well adapted to ...

  4. Compressed sensing techniques for receiver based post-compensation of transmitter's nonlinear distortions in OFDM systems

    KAUST Repository

    Owodunni, Damilola S.

    2014-04-01

    In this paper, compressed sensing techniques are proposed to linearize commercial power amplifiers driven by orthogonal frequency division multiplexing signals. The nonlinear distortion is considered as a sparse phenomenon in the time-domain, and three compressed sensing based algorithms are presented to estimate and compensate for these distortions at the receiver using a few and, at times, even no frequency-domain free carriers (i.e. pilot carriers). The first technique is a conventional compressed sensing approach, while the second incorporates a priori information about the distortions to enhance the estimation. Finally, the third technique involves an iterative data-aided algorithm that does not require any pilot carriers and hence allows the system to work at maximum bandwidth efficiency. The performances of all the proposed techniques are evaluated on a commercial power amplifier and compared. The error vector magnitude and symbol error rate results show the ability of compressed sensing to compensate for the amplifier\\'s nonlinear distortions. © 2013 Elsevier B.V.

  5. Physician-received scatter radiation with angiography systems used for interventional radiology: Comparison among many x-ray systems

    International Nuclear Information System (INIS)

    Chida, K.; Morishima, Y.; Inaba, Y.; Taura, M.; Ebata, A.; Takeda, K.; Shimura, H.; Zuguchi, M.

    2012-01-01

    Radiation protection for interventional radiology (IR) physicians is very important. Current IR X-ray systems tend to use flat-panel detectors (FPDs) rather than image intensifiers (IIs). The purpose of this study is to test the hypothesis that there is no difference in physician-received scatter radiation (PRSR) between FPD systems and II systems. This study examined 20 X-ray systems in 15 cardiac catheterisation laboratories (11 used a FPD and 9 used an II). The PRSR with digital cine-angiography and fluoroscopy were compared among the 20 X-ray systems using a phantom and a solid-state-detector electronic pocket dosemeter. The maximum PRSR exceeded the minimum PRSR by ∼12-fold for cine-angiography and ∼9-fold for fluoroscopy. For both fluoroscopy and digital cine-angiography, the PRSR had a statistically significant positive correlation with the entrance surface dose (fluoroscopy, r = 0.87; cine-angiography, r = 0.86). There was no statistically significant difference between the average PRSR of FPDs and IIs during either digital cine-angiography or fluoroscopy. There is a wide range of PRSR among the radiography systems evaluated. The PRSR correlated well with the entrance surface dose of the phantom in 20 X-ray units used for IR. Hence, decreasing the dose to the patient will also decrease the dose to staff. (authors)

  6. Central receiver solar thermal power system, phase 1. Progress report for period ending December 31, 1975

    Energy Technology Data Exchange (ETDEWEB)

    None

    1976-04-01

    The program objective is the preliminary design of a 10 MWe pilot solar power plant supported by major subsystem experiments. Progress is reported on the following task elements: 10 MWe pilot plant; collector subsystem design and analysis; receiver subsystem requirements; receiver subsystem design; thermal storage subsystem; electrical power generation subsystem; and pilot plant architectural engineering and support. (WDM)

  7. Acceptance test report, 241-SY-101 Flexible Receiver System, Phase 2 testing

    International Nuclear Information System (INIS)

    Ritter, G.A.

    1995-01-01

    This document summarizes the results of the Phase 2 acceptance test of the 241-SY-101 Flexible Receiver System (FRS). The FRS is one of six major components of the Equipment Removal System, which has been designed to retrieve, transport, and store the test mixer pump currently installed in Tank 241-SY-101. The purpose of this acceptance test is to verify the strength of the containment bag and bag bottom cinching mechanism. It is postulated that 68 gallons of waste could be trapped inside the pump internals. The bag must be capable of supporting this waste if it shakes loose and drains to the bottom of the bag after the bag bottom has been cinched closed. This acceptance test was performed at the Maintenance and Storage Facility (MASF) Facility in the 400 area on January 23, 1995. The bag assembly supported the weight of 920 kg (2,020 lbs) of water with no leakage or damage to the bag. This value meets the acceptance criteria of 910 kg of water and therefore the results were found to be acceptable. The maximum volume of liquid expected to be held up in the pump internals is 258 L (68 gallons), which corresponds to 410 kg. This test weight gives just over a safety factor of 2. The bag also supported a small shock load while it was filled with water when the crane hoisted the bag assembly up and down. Based on the strength rating of the bag components, the bag assembly should support 2--3 times the test weight of 910 kg

  8. Integrability in Dynamical Systems: Florida Workshop in Nonlinear Astronomy, 3rd, University of Florida, Gainesville, Oct. 1, 2, 1987, Proceedings

    International Nuclear Information System (INIS)

    Buchler, J.R.; Ipser, J.R.; Williams, C.A.

    1988-01-01

    Recent advances in theoretical celestial mechanics are examined in reviews and reports. Topics addressed include resonant integrable models of galaxies, new integrable systems, Painleve expansions for integrable and nonintegrable ordinary differential equations, and particle-simulation solutions of the Vlasov equation in general relativity. Consideration is given to repulsive and attractive double-bubble space-times, the integrability of magnetic-confinement systems, Hannay's angle and Berry's phase in the classical adiabatic motion of charged particles, the integrability of the nonlinear wave equations, normalization in the face of integrability, and simplifications toward the integrability of perturbed Keplerian systems

  9. First Contact: Expectations of Beginning Astronomy Students

    Science.gov (United States)

    Lacey, T. L.; Slater, T. F.

    1999-05-01

    Three hundred seven undergraduate students enrolled in Introductory Astronomy were surveyed at the beginning of class to determine their expectations for course content. The course serves as a survey of astronomy for non-science majors and is a distribution course for general education core requirements. The course has no prerequisites, meets three times each week for 50 minutes, and represents three semester credit hours. The university catalog describes the course with the title "PHYSICS 101 - Mysteries of the Sky" and the official course description is: a survey of the struggle to understand the Universe and our place therein. The structure, growth, methods, and limitations of science will be illustrated using the development of astronomy as a vehicle. Present day views of the Universe are presented. Two questions were asked as open response items: What made you decide to take this course? and What do you expect to learn in this course? The reasons that students cited to take the course, in order of frequency, were: interested in astronomy, interesting or fun sounding course, required general education fulfillment, recommendation by peer. Secondary reasons cited were required for major or minor, general interest in science, and was available in the schedule. Tertiary reasons listed were recommendation by advisor or orientation leader, inflate grade point average, and heard good things about the teacher. The students' expectations about what they would learn in the course were numerous. The most common objects listed, in order of frequency, were: stars, constellations, planets, galaxies, black holes, solar system, comets, galaxies, asteroids, moon, and Sun. More interesting were the aspects not specifically related to astronomy. These were weather, atmosphere, UFOs and the unexplained, generally things in the sky. A mid-course survey suggests that students expected to learn more constellations and that the topics would be less in-depth.

  10. The Astronomy Genealogy Project

    Science.gov (United States)

    Tenn, Joseph S.

    2014-01-01

    The Astronomy Genealogy Project, to be known as AstroGen, will list as many as possible of the world's astronomers with their academic parents (aka thesis advisors) and enable the reader to trace both academic ancestors and descendants. It will be very similar to the highly successful Mathematics Genealogy Project (MGP), available at http://genealogy.math.ndsu.nodak.edu. The MGP, which has been in operation since 1996, now contains the names of about 170,000 "mathematicians." These include many physicists and astronomers, as well as practitioners of related sciences. Mitchel Keller, the director of the MGP, has generously shared the software used in that project, and the American Astronomical Society (AAS) will host AstroGen, a project of the Historical Astronomy Division, on its website. We expect to start seeking entries soon, depending on the availability of computational assistance from the AAS IT department. We are seeking volunteers to help run the project. If you are interested, please contact me at joe.tenn@sonoma.edu.

  11. Astronomy books in Spanish

    Science.gov (United States)

    Fierro, Julieta

    Great cultures have created language. They have discovered its strength among other reasons for education. For a long time the Bible was one of the few books available in western culture, its influence is beyond any doubt. Many developing nations have no science books in their mother tongue. They might carry a few translations but these do not convey the local culture so it is harder for students to grasp the concepts and to build on what they know. Books, even if they are extremely simple, should be written in local languages because that will facilitate the conveying of knowledge and the creation of scientific culture. In the books examples that pertain to every day local life must be given, in particular examples that have to do with women. Women play a central role in developing nations by child bearing; if they become literate they will influence enormously the quality of their children's education, in particular their science comprehension. In Mexico a collection that includes astronomy books has recently been edited by the National Council for Culture and Arts. The books are small and light, which encourages middle-school students to carry them around and read them while traveling in public transportation, such as the subway. Every other page is a new subject, that carries illustrations, abstracts and conclusions. The astronomy books are on search for extraterrestrial life, the stars and the universe. These books are distributed nation-wide and are inexpensive. They have been written by Mexican astronomers.

  12. Making Astronomy Accessible

    Science.gov (United States)

    Grice, Noreen A.

    2011-05-01

    A new semester begins, and your students enter the classroom for the first time. You notice a student sitting in a wheelchair or walking with assistance from a cane. Maybe you see a student with a guide dog or carrying a Braille computer. Another student gestures "hello” but then continues hand motions, and you realize the person is actually signing. You wonder why another student is using an electronic device to speak. Think this can't happen in your class? According to the U.S. Census, one out of every five Americans has a disability. And some disabilities, such as autism, dyslexia and arthritis, are considered "invisible” disabilities. This means you have a high probability that one of your students will have a disability. As an astronomy instructor, you have the opportunity to reach a wide variety of learners by using creative teaching strategies. I will share some suggestions on how to make astronomy and your part of the universe more accessible for everyone.

  13. Classics in radio astronomy

    CERN Document Server

    Sullivan, Woodruff Turner

    1982-01-01

    Radio techniques were the nrst to lead astronomy away from the quiescent and limited Universe revealed by traditional observations at optical wave­ lengths. In the earliest days of radio astronomy, a handful of radio physicists and engineers made one startling discovery after another as they opened up the radio sky. With this collection of classic papers and the extensive intro­ ductory material, the reader can experience these exciting discoveries, as well as understand the developing techniques and follow the motivations which prompted the various lines of inquiry. For instance he or she will follow in detail the several attempts to detect radio waves from the sun at the turn of the century; the unravelling by Jansky of a "steady hiss type static"; the incredible story of Reber who built a 9 meter dish in his backyard in 1937 and then mapped the Milky Way; the vital discoveries by Hey and colleagues of radio bursts from the Sun and of a discrete source in the constellation of Cygnus; the development of re...

  14. Astronomy LITE Demonstrations

    Science.gov (United States)

    Brecher, Kenneth

    2006-12-01

    Project LITE (Light Inquiry Through Experiments) is a materials, software, and curriculum development project. It focuses on light, optics, color and visual perception. According to two recent surveys of college astronomy faculty members, these are among the topics most often included in the large introductory astronomy courses. The project has aimed largely at the design and implementation of hands-on experiences for students. However, it has also included the development of lecture demonstrations that employ novel light sources and materials. In this presentation, we will show some of our new lecture demonstrations concerning geometrical and physical optics, fluorescence, phosphorescence and polarization. We have developed over 200 Flash and Java applets that can be used either by teachers in lecture settings or by students at home. They are all posted on the web at http://lite.bu.edu. For either purpose they can be downloaded directly to the user's computer or run off line. In lecture demonstrations, some of these applets can be used to control the light emitted by video projectors to produce physical effects in materials (e.g. fluorescence). Other applets can be used, for example, to demonstrate that the human percept of color does not have a simple relationship with the physical frequency of the stimulating source of light. Project LITE is supported by Grant #DUE-0125992 from the NSF Division of Undergraduate Education.

  15. Books Received

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education. Books Received. Articles in Resonance – Journal of Science Education. Volume 1 Issue 1 January 1996 pp 118-118 Books Received. Books Received · More Details Fulltext PDF. Volume 1 Issue 2 February 1996 pp 120-120 Books Received. Books Received.

  16. 2011 Astronomy Day at McDonald Observatory

    Science.gov (United States)

    Preston, Sandra; Hemeway, M.; Wetzel, M.

    2012-01-01

    Our philosophy is that everyday is Astronomy Day because the McDonald Observatory's Frank N. Bash Visitors Center is open 362 days a year. So, how did we create a special celebration for the "Astronomy Day” declared by the Astronomical League? During September 26-29 we conducted 20 videoconferences and served 12,559 students with "Astronomy Day” programming. Connect2Texas provides bridging for a network of Texas-based museums and cultural, historical, and scientific organizations that offer educational content to schools throughout the state via videoconferencing. Connect2Texas connected McDonald Observatory to 334 schools; most of these schools were in Texas, but schools in a dozen other states also participated. While most schools had a "view-only" connection, at least 20 of the schools had interactive connections, whereby the students could ask questions of the presenter. Connect2Texas also collects evaluation information from the participating schools that we will use to produce a report for our funders and make modifications to future programs as need be. The videoconferences were offered free of charge. The theme for the 2011 Astronomy Day program was the Year of the Solar System, which aligns with NASA's theme for 2011 and 2012. By aligning with this NASA theme, we could leverage NASA artwork and materials to both advertise and enrich the learning experience. Videoconference materials also included pre- and post-videoconference assessment sheets, an inquiry based activity, and pre- and post-videoconference activities, all of which were made available online. One of the lessons learned from past Astronomy Day videoconferences is that the days the Astronomical League declares as "Astronomy Day” are not always good days for Texas schools to participate. So, we choose an Astronomy Day that meets the needs of Texas schools and our schedule - so any day can be Astronomy Day. 2011 Astronomy Day was made possible by The Meyer-Levy Charitable Trust.

  17. Fatigue life analysis of cracked gas receiver of emergency cut-off system in gas gathering station

    Science.gov (United States)

    Hu, Junzhi; Zhou, Jiyong; Li, Siyuan

    2017-06-01

    Small-scale air compressor and gas receiver are used as the driving gas of the emergency cut-off system in gas gathering station. Operation of block valve is ensured by starting and stopping compressor automatically. The frequent start-stop of compressor and the pressure fluctuation pose a threat to the service life of gas receiver, and then affect normal operation of the emergency cut-off system and security of gas gathering station. In this paper, the fatigue life of a pressure vessel with axial semi-elliptical surface crack in the inner wall is analyzed under the varying pressure by means of the theory of fracture mechanics. The influences of the amplitude of pressure fluctuation and the initial crack size on the residual life of gas receiver are discussed. It provides a basis for setting the working parameters of gas receiver of emergency cut-off system and determining the maintenance cycle.

  18. Analysis of impact of “strong DC and weak AC” on receiving-end power system

    Science.gov (United States)

    Wang, Qiang; Li, Tianran; Yang, Pengcheng

    2018-02-01

    The rapid development of UHVDC transmission project has brought abundant power supply to the receiving-end power system area, but also many security and stability problems. This paper summarizes four elements that affect the strength of AC system, and then simulates the most basic two-terminal single-pole UHV transmission system by MATLAB/Simulink. It analyses the impact of receiving-end AC power system strength on real-time power, frequency and voltage. Finally, in view of operation risk of “strong DC and weak AC”, this paper puts forward three countermeasures.

  19. Performance Analysis of a Six-Port Receiver in a WCDMA Communication System including a Multipath Fading Channel

    Directory of Open Access Journals (Sweden)

    A. O. Olopade

    2014-01-01

    Full Text Available Third generation communication systems require receivers with wide bandwidth of operation to support high transmission rates and are also reconfigurable to support various communication standards with different frequency bands. An ideal software defined radio (SDR will be the absolute answer to this requirement but it is not achievable with the current level of technology. This paper proposes the use of a six-port receiver (SPR front-end (FE in a WCDMA communication system. A WCDMA end-to-end physical layer MATLAB demo which includes a multipath channel distortion block is used to determine the viability of the six-port based receiver. The WCDMA signal after passing through a multipath channel is received using a constructed SPR FE. The baseband signal is then calibrated and corrected in MATLAB. The six-port receiver performance is measured in terms of bit error rate (BER. The signal-to-noise ratio (SNR of the transmitted IQ data is varied and the BER profile of the communication system is plotted. The effect of the multipath fading on the receiver performance and the accuracy of the calibration algorithm are obtained by comparing two different measured BER curves for different calibration techniques to the simulated BER curve of an ideal receiver.

  20. An Efficient Rank Adaptation Algorithm for Cellular MIMO Systems with IRC Receivers

    DEFF Research Database (Denmark)

    Mahmood, Nurul Huda; Berardinelli, Gilberto; Tavares, Fernando Menezes Leitão

    2014-01-01

    Multiple transmit and receive antennas introduce additional degrees of freedom, which can be used to increase the number of spatial channels between a transmitter-receiver pair. Alternately, the additional degrees of freedom can be used to improve the interference resilience property with the help...... algorithm based on an estimate of the mean signal-to-interference-plus-noise ratio (SINR) at an IRC receiver; wherein, we use results from random matrix theory to derive the expression for the mean post-IRC SINR in the presence of interferers with unequal powers. The performance of the proposed algorithm...

  1. Systems and methods for direct thermal receivers using near blackbody configurations

    Energy Technology Data Exchange (ETDEWEB)

    Wagner, Michael; Ma, Zhiwen; Martinek, Janna; Neises, Ty; Turchi, Craig

    2018-04-17

    An aspect of the present disclosure is a receiver for receiving radiation from a heliostat array that includes at least one external panel configured to form an internal cavity and an open face. The open face is positioned substantially perpendicular to a longitudinal axis and forms an entrance to the internal cavity. The receiver also includes at least one internal panel positioned within the cavity and aligned substantially parallel to the longitudinal axis, and the at least one internal panel includes at least one channel configured to distribute a heat transfer medium.

  2. The IAU 2009 System of Astronomical Constants: The Report of the IAU Working Group on Numerical Standards for Fundamental Astronomy

    Science.gov (United States)

    2011-01-01

    instance, this group (1) decided on the two-tiered approach to the astronomical constants that we are currently using (i.e. having both an official system...update (2008AGUFM.G33A0673C). Geocentric gravitation constant, GME The geocentric gravitation constant, GME, is taken from Ries et al. (1992). TCB

  3. Adaptive Jamming Suppression in Coherent FFH System Using Weighted Equal Gain Combining Receiver over Fading Channels with Imperfect CSI

    Directory of Open Access Journals (Sweden)

    Yishan He

    2015-01-01

    Full Text Available Fast frequency hopping (FFH is commonly used as an antijamming communication method. In this paper, we propose efficient adaptive jamming suppression schemes for binary phase shift keying (BPSK based coherent FFH system, namely, weighted equal gain combining (W-EGC with the optimum and suboptimum weighting coefficient. We analyze the bit error ratio (BER of EGC and W-EGC receivers with partial band noise jamming (PBNJ, frequency selective Rayleigh fading, and channel estimation errors. Particularly, closed-form BER expressions are presented with diversity order two. Our analysis is verified by simulations. It is shown that W-EGC receivers significantly outperform EGC. As compared to the maximum likelihood (ML receiver in conventional noncoherent frequency shift keying (FSK based FFH, coherent FFH/BPSK W-EGC receivers also show significant advantages in terms of BER. Moreover, W-EGC receivers greatly reduce the hostile jammers’ jamming efficiency.

  4. Minimum BER Receiver Filters with Block Memory for Uplink DS-CDMA Systems

    Directory of Open Access Journals (Sweden)

    Mérouane Debbah

    2008-05-01

    Full Text Available The problem of synchronous multiuser receiver design in the case of direct-sequence single-antenna code division multiple access (DS-CDMA uplink networks is studied over frequency selective fading channels. An exact expression for the bit error rate (BER is derived in the case of BPSK signaling. Moreover, an algorithm is proposed for finding the finite impulse response (FIR receiver filters with block memory such that the exact BER of the active users is minimized. Several properties of the minimum BER FIR filters with block memory are identified. The algorithm performance is found for scenarios with different channel qualities, spreading code lengths, receiver block memory size, near-far effects, and channel mismatch. For the BPSK constellation, the proposed FIR receiver structure with block memory has significant better BER with respect to Eb/N0 and near-far resistance than the corresponding minimum mean square error (MMSE filters with block memory.

  5. Minimum BER Receiver Filters with Block Memory for Uplink DS-CDMA Systems

    Directory of Open Access Journals (Sweden)

    Debbah Mérouane

    2008-01-01

    Full Text Available Abstract The problem of synchronous multiuser receiver design in the case of direct-sequence single-antenna code division multiple access (DS-CDMA uplink networks is studied over frequency selective fading channels. An exact expression for the bit error rate (BER is derived in the case of BPSK signaling. Moreover, an algorithm is proposed for finding the finite impulse response (FIR receiver filters with block memory such that the exact BER of the active users is minimized. Several properties of the minimum BER FIR filters with block memory are identified. The algorithm performance is found for scenarios with different channel qualities, spreading code lengths, receiver block memory size, near-far effects, and channel mismatch. For the BPSK constellation, the proposed FIR receiver structure with block memory has significant better BER with respect to and near-far resistance than the corresponding minimum mean square error (MMSE filters with block memory.

  6. Distributed processing in receivers based on tensor for cooperative communications systems

    OpenAIRE

    Igor FlÃvio SimÃes de Sousa

    2014-01-01

    In this dissertation, we present a distributed data estimation and detection approach for the uplink of a network that uses CDMA at transmitters (users). The analyzed network can be represented by an undirected and connected graph, where the nodes use a distributed estimation algorithm based on consensus averaging to perform joint channel and symbol estimation using a receiver based on tensor signal processing. The centralized receiver, developed for a central base station, and the distribute...

  7. To See the Unseen: A History of Planetary Radar Astronomy

    Science.gov (United States)

    Butrica, Andrew J.

    1996-01-01

    This book relates the history of planetary radar astronomy from its origins in radar to the present day and secondarily to bring to light that history as a case of 'Big Equipment but not Big Science'. Chapter One sketches the emergence of radar astronomy as an ongoing scientific activity at Jodrell Bank, where radar research revealed that meteors were part of the solar system. The chief Big Science driving early radar astronomy experiments was ionospheric research. Chapter Two links the Cold War and the Space Race to the first radar experiments attempted on planetary targets, while recounting the initial achievements of planetary radar, namely, the refinement of the astronomical unit and the rotational rate and direction of Venus. Chapter Three discusses early attempts to organize radar astronomy and the efforts at MIT's Lincoln Laboratory, in conjunction with Harvard radio astronomers, to acquire antenna time unfettered by military priorities. Here, the chief Big Science influencing the development of planetary radar astronomy was radio astronomy. Chapter Four spotlights the evolution of planetary radar astronomy at the Jet Propulsion Laboratory, a NASA facility, at Cornell University's Arecibo Observatory, and at Jodrell Bank. A congeries of funding from the military, the National Science Foundation, and finally NASA marked that evolution, which culminated in planetary radar astronomy finding a single Big Science patron, NASA. Chapter Five analyzes planetary radar astronomy as a science using the theoretical framework provided by philosopher of science Thomas Kuhn. Chapter Six explores the shift in planetary radar astronomy beginning in the 1970s that resulted from its financial and institutional relationship with NASA Big Science. Chapter Seven addresses the Magellan mission and its relation to the evolution of planetary radar astronomy from a ground-based to a space-based activity. Chapters Eight and Nine discuss the research carried out at ground

  8. Terahertz heterodyne technology for astronomy and planetary science

    NARCIS (Netherlands)

    Wild, Wolfgang

    2007-01-01

    Heterodyne detection techniques play an important role in high-resolution spectroscopy in astronomy and planetary science. In particular, heterodyne technology in the Terahertz range has rapidly evolved in recent years. Cryogenically cooled receivers approaching quantum-limited sensitivity have been

  9. Astronomy Enrollments and Degrees: Results from the 2012 Survey of Astronomy Enrollments and Degrees. Focus On

    Science.gov (United States)

    Mulvey, Patrick; Nicholson, Starr

    2014-01-01

    Interest in astronomy degrees in the U.S. remains strong, with astronomy enrollments at or near all-time highs for the 2012-13 academic year. The total number of students taking an introductory astronomy course at a degree-granting physics or astronomy department is approaching 200,000. Enrollments in introductory astronomy courses have been…

  10. The Network for Astronomy in Education in Southwest New Mexico

    Science.gov (United States)

    Neely, B.

    1998-12-01

    The Network for Astronomy in Education was organized to use astronomy as a motivational tool to teach science methods and principles in the public schools. NFO is a small private research observatory, associated with the local University, Western New Mexico. We started our program in 1996 with an IDEA grant by introducing local teachers to the Internet, funding a portable planetarium (Starlab) for the students, and upgrading our local radio linked computer network. Grant County is a rural mining and ranching county in Southwest New Mexico. It is ethnically diverse and has a large portion of the population below the poverty line. It's dryness and 6000' foot elevation, along with dark skies, suite it to the appreciation of astronomy. We now have 8 local schools involved in astronomy at some level. Our main programs are the Starlab and Project Astro, and we will soon install a Sidewalk Solar System in the center of Silver City.

  11. Social Representations of the Integrated High School Students about Astronomy

    Science.gov (United States)

    Barbosa, Jose Isnaldo de Lima; Voelzke, Marcos Rincon

    2017-07-01

    Astronomy issues are not always adequately handled in the formal education system, as well as, their dissemination in the media is often loaded with sensationalism. However, in this context the students are forming their explanations about it. Therefore, this work has the objective of identifying the possible social representations of students from the Integrated High School on the inductor term Astronomy. It is basically a descriptive research, therefore, a quali-qualitative approach was adopted. The procedures for obtaining the data occurred in the form of a survey, and they involved 653 subjects students from the Integrated High School. The results indicate that the surveyed students have social representations of the object Astronomy, which are based on elements from the formal education space, and also disclosed in the media. In addition, they demonstrate that the students have information about Astronomy, and a value judgment in relation to this science.

  12. Astronomy a visual guide

    CERN Document Server

    Garlick, Mark A

    2004-01-01

    Space has fascinated man and challenged scientists for centuries and astronomy is the oldest and one of the most dynamic of the sciences. Here is a book that will stimulate your curiosity and feed your imagination. Detailed and fascinating text is clearly and richly illustrated with fabulous, vibrant photographs and diagrams. This is a comprehensive guide to understanding and observing the night sky, from distant stars and galaxies to our neighbouring planets; from comets to shooting stars; from eclipses to black holes. With details of the latest space probes, a series of monthly sky maps to provide guidance for the amateur observer and the latest photos from space, this book brings the beauty and wonder of our universe into your living room and will have you reaching for the telescope!

  13. Gravitational wave astronomy

    CERN Multimedia

    CERN. Geneva

    2016-01-01

    In the past year, the LIGO-Virgo Collaboration announced the first secure detection of gravitational waves. This discovery heralds the beginning of gravitational wave astronomy: the use of gravitational waves as a tool for studying the dense and dynamical universe. In this talk, I will describe the full spectrum of gravitational waves, from Hubble-scale modes, through waves with periods of years, hours and milliseconds. I will describe the different techniques one uses to measure the waves in these bands, current and planned facilities for implementing these techniques, and the broad range of sources which produce the radiation. I will discuss what we might expect to learn as more events and sources are measured, and as this field matures into a standard part of the astronomical milieu.

  14. Astronomy in laboratory

    Science.gov (United States)

    Suzuki, B.

    2006-08-01

    It is not easy to practice astronomical observation in a high school. It is difficult to teach authentic astronomy because real-world conditions cannot be reproduced in the classroom. However, the following ideas produce some interesting experiments. 1. The reappearance experiment of the meteor spectrum. We produced emission spectra by using a gas burner and welding. It can be understood that the luminosity of emission lines varies according to temperature. Furthermore, we mixed in liquid chlorides of Na, Ca, Fe, Sg, Si, etc., in different proportions tomimic different meteor spectra. We then observed the time changes of the luminosity using a video camcorder that we attached to a spectroscope. The spectrum in the experiment closely resembled that of a meteor. 2. The verification of the black-drop phenomenon.Long ago, the black-drop phenomenon became important in the case of Venus's passage between the Earth and the Sun, a transit of Venus. We tried to reproduce this phenomenon by using a small ball painted black, solar light, and an artificial illuminant. The profile of the reproduced image was then checked in detail. We found that this phenomenon depended on the influence of the limb darkening of the Sun, the scintillation of the Earth's atmosphere, and the optical performance of the telescope. Furthermore, we imitated Venus's atmosphere as an additional experiment by applying oil on the surface of the small ball. It resulted in an interesting profile but was not a sufficient experiment. Of course, these experiments are in conditions that are very different from the actual physical conditions. However, we think that they provide a very effective method for enhancing students' interest in astronomy. We are planning other experiments with similar themes.

  15. Design and performance of a one square meter proportional counter system for hard X-ray astronomy

    International Nuclear Information System (INIS)

    Bazzano, A.; Boccaccini, L.; La Padula, C.D.; Mastropietro, M.; Patriarca, R.; Polcaro, F.; Ubertini, P.

    1983-01-01

    A versatile balloon borne hard X-ray experiment with a very large area (approx.= 1.1 m 2 ) and high spectral resolution has been developed for the study of the hard X-ray sources in the energy range 20-180 keV. The telescope consists of four multiwire proportional chambers (MWPC) that have a geometrical sensitive area of 2700 cm 2 each. The detector system has a sensitivity of approx.= 10 -5 photons cm -2 s -1 keV -1 during a typical balloon observation. A background rate of approx.= 3 x 10 -4 counts cm -2 s -1 keV -1 was observed in the operative energy range at 2.4 gm/cm 2 ceiling altitude and geographic latitude of 38 0 N. The design details, fabrication and flight performance of the instrument are briefly discussed with reference to the effectiveness of background reduction and other test parameters. (orig.)

  16. Planets in Inuit Astronomy

    Science.gov (United States)

    MacDonald, John

    2018-02-01

    Inuit are an indigenous people traditionally inhabiting the Arctic and sub-Arctic regions of Greenland, Canada, Alaska, and parts of Russia's Chukchi Peninsula. Across this vast region, Inuit society, while not entirely homogeneous either culturally or linguistically, nevertheless shares a fundamental cosmology, in part based on a common understanding of the sky and its contents. Traditionally, Inuit used prominent celestial objects—the sun, moon, and major circumpolar asterisms—as markers for estimating the passage of time, as wayfinding and directional aids, and, importantly, as the basis of several of the foundational myths and legends underpinning their society's social order and mores. Random inquiries on Inuit astronomy made by European visitors after initial contact through the mid-18th and early 20th centuries were characteristically haphazard and usually peripheral to some other line of ethnological enquiry, such as folklore or mythology. In addition, the early accounts of Inuit star lore were often prone to misrepresentation due to several factors, including European cultural bias, translation inadequacies, a deficiency of general astronomical knowledge on the part of most commentators, and, most significantly, a failure—sometimes due to lack of opportunity—to conduct systematic observations of the sky in the presence of Inuit knowledge holders. Early accounts therefore tended to diminish the cultural significance of Inuit astronomy, almost to the point of insignificance. Unfortunately, by the time systematic fieldwork began on the topic, in the mid-1980s, unalloyed information on Inuit astronomical knowledge was already elusive, more and more compromised by European acculturation and substitution and, notably, by light pollution—a consequence of the increasing urbanization of Inuit communities beginning in the late 1950s. For the residents of most Arctic settlements, street lights reflecting off the snow have virtually eliminated the evocative

  17. Astronomy at the frontiers of science

    CERN Document Server

    2011-01-01

    Astronomy is by nature an interdisciplinary activity: it involves mathematics, physics, chemistry and biology. Astronomers use (and often develop) the latest technology, the fastest computers and the most refined software.  In this book twenty-two leading scientists from nine countries talk about how astronomy interacts with these other sciences. They describe modern instruments used in astronomy and the relations between astronomy and technology, industry, politics and philosophy. They also discuss what it means to be an astronomer, the history of astronomy, and the place of astronomy in society today.   The book contains twenty chapters grouped in four parts: ASTRONOMY AND PHYSICS discusses the place of astronomy among various branches of (mostly high-energy) physics. ASTRONOMY IN SOCIETY describes not only the historical context of astronomy, but issues facing astronomers today, including funding, planning, worldwide collaboration and links with industry. THE TOOLS OF OBSERVATION AND THE PROFESSION OF AS...

  18. SWUIS-A: A Versatile, Low-Cost UV/VIS/IR Imaging System for Airborne Astronomy and Aeronomy Research

    Science.gov (United States)

    Durda, Daniel D.; Stern, S. Alan; Tomlinson, William; Slater, David C.; Vilas, Faith

    2001-01-01

    We have developed and successfully flight-tested on 14 different airborne missions the hardware and techniques for routinely conducting valuable astronomical and aeronomical observations from high-performance, two-seater military-type aircraft. The SWUIS-A (Southwest Universal Imaging System - Airborne) system consists of an image-intensified CCD camera with broad band response from the near-UV to the near IR, high-quality foreoptics, a miniaturized video recorder, an aircraft-to-camera power and telemetry interface with associated camera controls, and associated cables, filters, and other minor equipment. SWUIS-A's suite of high-quality foreoptics gives it selectable, variable focal length/variable field-of-view capabilities. The SWUIS-A camera frames at 60 Hz video rates, which is a key requirement for both jitter compensation and high time resolution (useful for occultation, lightning, and auroral studies). Broadband SWUIS-A image coadds can exceed a limiting magnitude of V = 10.5 in <1 sec with dark sky conditions. A valuable attribute of SWUIS-A airborne observations is the fact that the astronomer flies with the instrument, thereby providing Space Shuttle-like "payload specialist" capability to "close-the-loop" in real-time on the research done on each research mission. Key advantages of the small, high-performance aircraft on which we can fly SWUIS-A include significant cost savings over larger, more conventional airborne platforms, worldwide basing obviating the need for expensive, campaign-style movement of specialized large aircraft and their logistics support teams, and ultimately faster reaction times to transient events. Compared to ground-based instruments, airborne research platforms offer superior atmospheric transmission, the mobility to reach remote and often-times otherwise unreachable locations over the Earth, and virtually-guaranteed good weather for observing the sky. Compared to space-based instruments, airborne platforms typically offer

  19. Introducing Astronomy Related Research into Non-Astronomy Courses

    Science.gov (United States)

    Walker, Douglas

    The concern over the insufficient number of students choosing to enter the science and engineering fields has been discussed and documented for years. While historically addressed at the national level, many states are now recognizing that the lack of a highly-skilled technical workforce within their states' borders has a significant effect on their economic health. Astronomy, as a science field, is no exception. Articles appear periodically in the most popular astronomy magazines asking the question, "Where are the young astronomers?" Astronomy courses at the community college level are normally restricted to introductory astronomy I and II level classes that introduce the student to the basics of the night sky and astronomy. The vast majority of these courses is geared toward the non-science major and is considered by many students to be easy and watered down courses in comparison to typical physics and related science courses. A majority of students who enroll in these classes are not considering majors in science or astronomy since they believe that science is "boring and won't produce any type of career for them." Is there any way to attract students? This paper discusses an approach being undertaken at the Estrella Mountain Community College to introduce students in selected mathematics courses to aspects of astronomy related research to demonstrate that science is anything but boring. Basic statistical techniques and understanding of geometry are applied to a large virgin data set containing the magnitudes and phase characteristics of sets of variable stars. The students' work consisted of developing and presenting a project that explored analyzing selected aspects of the variable star data set. The description of the data set, the approach the students took for research projects, and results from a survey conducted at semester's end to determine if student's interest and appreciation of astronomy was affected are presented. Using the data set provided, the

  20. Special Session 4: Astronomy Education between Past and Future

    Science.gov (United States)

    de Greve, Jean-Pierre

    2010-11-01

    The special session aims at discussing an integrated approach of the different efforts to increase and promote the teaching and learning of astronomy in the world, with emphasis on developing countries. To this end, attention will be given to research on education, specifically in the field of physics, to best practices of the use of astronomy in educational systems (specifically in developing countries), and to innovative learning initiatives other than formal education. The Special Session aims also at creating a universal perspective wherein modern (post-Copernican) astronomy will presented as an intellectual cumulus. The objective of the session is to disseminate best practices in teaching and learning activities of astronomy and to give an opportunity to learn about initiatives in different cultural and socio-economic settings. The special session also wants to give food-for-thought and proposals for reflection for an integrative approach, and for optimization processes, to enhance the interest in astronomy and its role as a trigger towards science education in the educational systems, with emphasis on the developing countries. The outcome should be a sensitization of teachers and students alike to the concept of a universal history of astronomy and creation of some reliable source material which can be used as a teaching aid in a culture-specific context. The outcome could be a set of recommendations for future integrated actions, and eventually recommendations on new initiatives, framed into the new decadal policy plan.

  1. Design and performance of a one square meter proportional counter system for hard X-ray astronomy

    Energy Technology Data Exchange (ETDEWEB)

    Bazzano, A.; Boccaccini, L.; La Padula, C.D.; Mastropietro, M.; Patriarca, R.; Polcaro, F.; Ubertini, P. (Consiglio Nazionale delle Ricerche, Frascati (Italy). Lab. di Astrofisica Spaziale); Manchanda, R.K. (Consiglio Nazionale delle Ricerche, Frascati (Italy). Lab. di Astrofisica Spaziale; Tata Inst. of Fundamental Research, Bombay (India))

    1983-09-01

    A versatile balloon borne hard X-ray experiment with a very large area (approx.= 1.1 m/sup 2/) and high spectral resolution has been developed for the study of the hard X-ray sources in the energy range 20-180 keV. The telescope consists of four multiwire proportional chambers (MWPC) that have a geometrical sensitive area of 2700 cm/sup 2/ each. The detector system has a sensitivity of approx.= 10/sup -5/ photons cm/sup -2/ s/sup -1/ keV/sup -1/ during a typical balloon observation. A background rate of approx.= 3 x 10/sup -4/ counts cm/sup -2/ s/sup -1/ keV/sup -1/ was observed in the operative energy range at 2.4 gm/cm/sup 2/ ceiling altitude and geographic latitude of 38/sup 0/N. The design details, fabrication and flight performance of the instrument are briefly discussed with reference to the effectiveness of background reduction and other test parameters.

  2. Preservice elementary teachers learning of astronomy

    Science.gov (United States)

    Fidler, Chuck Gary

    The dissertation presents a new approach for the study of preservice elementary teacher astronomy education. The approach suggests that learning astronomical concepts are facilitated by greater sophistication in scale perception and spatial-aptitude. This dissertation is underscored by the national call for elementary science education reform efforts and suggests certain strategies shown more effective for the development of accurate astronomical comprehension. The present research study describes how preservice elementary teachers conceptualize and communicate ideas about Space. Instead of assuming a universal mental conception of cosmic orientations and relationships, the dissertation claims that the perception of Space related dimensions vary among preservice elementary teachers. Furthermore, the dissertation suggests individual perceptions of the scale sizes and orientations of celestial systems have direct influences on mental models used to organize and communicate astronomical information. The development of inaccurate mental models of the scaled dimensions of Space may perpetuate the teacher-student cycle of misconception and naive-theory generation among children in elementary education settings. The ability to conceptualize the vast cosmos is facilitated by the minds ability to think about vast scales and orientations of celestial objects. The Earth-based perspective of astronomy education compels the learner to think about astronomical principles within imaginary frames of reference and across unfamiliar scaled dimensions. Therefore, mental astronomical model building is underscored by the perception of scale and cosmic spatiality. This study suggests these cognitive skill sets are interconnected and facilitate the learning of accurate astronomy principles; as well as play an important role when designing an astronomy education program for preservice elementary teachers. This research study is comprised of three separate standalone articles designed and

  3. Safety and immunogenicity of yellow fever 17D vaccine in adults receiving systemic corticosteroid therapy: an observational cohort study.

    Science.gov (United States)

    Kernéis, Solen; Launay, Odile; Ancelle, Thierry; Iordache, Laura; Naneix-Laroche, Véronique; Méchaï, Frédéric; Fehr, Thierry; Leroy, Jean-Philippe; Issartel, Bertrand; Dunand, Jean; van der Vliet, Diane; Wyplosz, Benjamin; Consigny, Paul-Henri; Hanslik, Thomas

    2013-09-01

    To assess the safety and immunogenicity of live attenuated yellow fever (YF) 17D vaccine in adults receiving systemic corticosteroid therapy. All adult travelers on systemic corticosteroid therapy who had received the YF17D vaccine in 24 French vaccination centers were prospectively enrolled and matched with healthy controls (1:2) on age and history of YF17D immunization. Safety was assessed in a self-administered standardized questionnaire within 10 days after immunization. YF-specific neutralizing antibody titers were measured 6 months after vaccination in patients receiving corticosteroids. Between July 2008 and February 2011, 102 vaccine recipients completed the safety study (34 receiving corticosteroids and 68 controls). The median age was 54.9 years (interquartile range [IQR] 45.1-60.3 years) and 45 participants had a history of previous YF17D immunization. The median time receiving corticosteroid therapy was 10 months (IQR 1-67 months) and the prednisone or equivalent dosage was 7 mg/day (IQR 5-20). Main indications were autoimmune diseases (n = 14), rheumatoid arthritis (n = 9), and upper respiratory tract infections (n = 8). No serious adverse event was reported; however, patients receiving corticosteroids reported more frequent moderate/severe local reactions than controls (12% and 2%, respectively; relative risk 8.0, 95% confidence interval 1.4-45.9). All subjects receiving corticosteroids who were tested (n = 20) had neutralizing antibody titers >10 after vaccination. After YF17D immunization, moderate/severe local reactions may be more frequent in patients receiving systemic corticosteroid therapy. Immunogenicity seems satisfactory. Large-scale studies are needed to confirm these results. Copyright © 2013 by the American College of Rheumatology.

  4. Metal Mesh Filters for Terahertz Receivers, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — The technical objective of this SBIR program is to develop and demonstrate metal mesh filters for use in NASA's low noise receivers for terahertz astronomy and...

  5. A Combined Time Domain Impedance Probe And Plasma Wave Receiver System For Small Satellite Applications.

    Science.gov (United States)

    Spencer, E. A.; Clark, D. C.; Vadepu, S. K.; Patra, S.

    2017-12-01

    A Time Domain Impedance Probe (TDIP) measures electron density and electron neutral collision frequencies in the ionosphere. This instrument has been tested on a sounding rocket flight and is now being further developed to fly on a NASA Undergraduate Student Instrument Program (USIP) cubesat to be launched out of the ISS in 2019. Here we report on the development of a new combined TDIP and plasma wave instrument that can be used on cubesat platforms to measure local electron parameters, and also to receive or transmit electron scale waves. This combined instrument can be used to study short time and space scale phenomena in the upper ionosphere using only RF signals. The front end analog circuitry is dual-purposed to perform active or passive probing of the ambient plasma. Two dipole antennas are used, one is optimzed for impedance measurements, while the other is optimized for transmitter-receiver performance. We show our circuit realization, and initial results from laboratory measurements using the TDIP prototype modified for receiver function. We also show Finite Difference Time Domain (FDTD) simulations of an electrically long antenna immersed in a magnetized plasma used to optimize the transmitter receiver performance.

  6. Compressed sensing techniques for receiver based post-compensation of transmitter's nonlinear distortions in OFDM systems

    KAUST Repository

    Owodunni, Damilola S.; Ali, Anum Z.; Quadeer, Ahmed Abdul; Al-Safadi, Ebrahim B.; Hammi, Oualid; Al-Naffouri, Tareq Y.

    2014-01-01

    -domain, and three compressed sensing based algorithms are presented to estimate and compensate for these distortions at the receiver using a few and, at times, even no frequency-domain free carriers (i.e. pilot carriers). The first technique is a conventional

  7. Novel Received Signal Strength-Based Indoor Location System: Development and Testing

    Directory of Open Access Journals (Sweden)

    Álvarez Yuri

    2010-01-01

    Full Text Available A received signal strength- (RSS-based indoor location method (ILS for person/assets location in indoor scenarios is presented in this paper. Theoretical bases of the method are the integral equations relating the electromagnetic (EM fields with their sources, establishing a cost function relating the measured field at the receivers and the unknown position of the transmitter. The aim is to improve the EM characterization of the scenario yielding in a more accurate indoor location method. Regarding network infrastructure implementation, a set of receivers are deployed through the coverage area, measuring the RSS value from a transmitter node which is attached to the asset to be located. The location method is evaluated in several indoor scenarios using portable measurement equipment. The next step has been the network hardware implementation using a wireless sensor network: for this purpose, ZigBee nodes have been selected. Finally, RSS measurements variability due to multipath effects and nonline-of-sight between transmitter and receiver nodes is mitigated using calibration and a correction based on the difference between the free space field decay law and the measured RSS.

  8. Demographics in Astronomy and Astrophysics

    Science.gov (United States)

    Ulvestad, James S.

    2011-05-01

    Astronomy has been undergoing a significant demographic shift over the last several decades, as shown by data presented in the 2000 National Research Council (NRC) report "Federal Funding of Astronomical Research," and the 2010 NRC report, "New Worlds, New Horizons in Astronomy and Astrophysics." For example, the number of advertised postdoctoral positions in astronomy has increased much more rapldly than the number of faculty positions, contributing to a holding pattern of early-career astronomers in multiple postdoctoral positions. This talk will summarize some of the current demographic trends in astronomy, including information about gender and ethnic diversity, and describe some of the possible implications for the future. I thank the members of the Astro2010 Demographics Study Group, as well as numerous white-paper contributors to Astro2010, for providing data and analyses.

  9. Essays on medieval computational astronomy

    CERN Document Server

    Bergón, José Chabás

    2014-01-01

    In Essays on Medieval Computational Astronomy the authors provide examples of original and intelligent approaches and solutions given by medieval astronomers to the problems of their discipline, mostly presented in the form of astronomical tables.

  10. History of the modern astronomy

    International Nuclear Information System (INIS)

    Herrmann, D.B.

    1984-01-01

    The book treats the following topics: structure and motion of the sky - classical astronomy, origin of astrophysics, macrocosm - microcosm, and techniques and organization of research. 86 black-and-white and 15 color plates are included

  11. Adaptive Optics, LLLFT Interferometry, Astronomy

    National Research Council Canada - National Science Library

    2002-01-01

    We propose to build a three telescope Michelson optical interferometer equipped with wavefront compensation technology as a demonstration and test bed for high resolution Deep Space Surveillance (DSS) and Astronomy...

  12. Lunar based gamma ray astronomy

    International Nuclear Information System (INIS)

    Haymes, R.C.

    1985-01-01

    Gamma ray astronomy represents the study of the universe on the basis of the electromagnetic radiation with the highest energy. Gamma ray astronomy provides a crucial tool for the understanding of astronomical phenomena, taking into account nucleosynthesis in supernovae, black holes, active galaxies, quasars, the sources of cosmic rays, neutron stars, and matter-antimatter annihilation. Difficulties concerning the conduction of studies by gamma ray astronomy are related to the necessity to perform such studies far from earth because the atmosphere is a source of gamma rays. Studies involving the use of gamma ray instruments in earth orbit have been conducted, and more gamma ray astronomy observations are planned for the future. Imperfections of studies conducted in low earth orbit could be overcome by estalishing an observatory on the moon which represents a satellite orbiting at 60 earth radii. Details concerning such an observatory are discussed. 5 references

  13. Astronomy Week in Madeira, Portugal

    Science.gov (United States)

    Augusto, P.; Sobrinho, J. L.

    2012-05-01

    The outreach programme Semanas da Astronomia (Astronomy Weeks) is held in late spring or summer on the island of Madeira, Portugal. This programme has been attracting enough interest to be mentioned in the regional press/TV/radio every year and is now, without doubt, the astronomical highlight of the year on Madeira. We believe that this programme is a good case study for showing how to attract the general public to astronomy in a small (population 250 000, area 900 km2) and fairly isolated place such as Madeira. Our Astronomy Weeks have been different each year and have so far included exhibitions, courses, talks, a forum, documentaries, observing sessions (some with blackouts), music and an astro party. These efforts may contribute towards putting Madeira on the map with respect to observational astronomy, and have also contributed to the planned installation of two observatories in the island.

  14. From astronomy to data science

    Science.gov (United States)

    Rodriguez Zaurín, Javier

    2018-01-01

    After almost ten years in academia I took one of the best decisions of my life: to leave it. This is my experience transitioning from astronomy to data science in search of a more open, fast-paced working environment.

  15. Critical Issues in the Philosophy of Astronomy and Cosmology

    Science.gov (United States)

    Dick, Steven J.

    2016-01-01

    Although the philosophy of science and of specific sciences such as physics, chemistry, and biology are well-developed fields with their own books and journals, the philosophy of astronomy and cosmology have received little systematic attention. At least six categories of problems may be identified in the astronomical context: 1) the nature of reasoning, including the roles of observation, theory, simulation, and analogy, as well as the limits of reasoning, starkly evident in the anthropic principle, fine-tuning, and multiverse controversies; 2) the often problematic nature of evidence and inference, especially since the objects of astronomical interest are for the most part beyond experiment and experience;3) the influence of metaphysical preconceptions and non-scientific worldviews on astronomy, evidenced, for example in the work of Arthur S. Eddington and many other astronomers; 4) the epistemological status of astronomy and its central concepts, including the process of discovery, the problems of classification, and the pitfalls of definition (as in planets); 5) the role of technology in shaping the discipline of astronomy and our view of the universe; and 6) the mutual interactions of astronomy and cosmology with society over time. Discussion of these issues should draw heavily on the history of astronomy as well as current research, and may reveal an evolution in approaches, techniques, and goals, perhaps with policy relevance. This endeavor should also utilize and synergize approaches and results from philosophy of science and of related sciences such as physics (e.g. discussions on the nature of space and time). Philosophers, historians and scientists should join this new endeavor. A Journal of the Philosophy of Astronomy and Cosmology (JPAC) could help focus attention on their studies.

  16. Historic Radio Astronomy Working Group

    Science.gov (United States)

    2007-06-01

    This special issue of Astronomische Nachrichten contains the proceedings of a session of the Historic Radio Astronomy Working Group of the International Astronomical Union that took place during the 26th General Assembly of the IAU in Prague on 17th August 2006. In addition to the talks presented in Prague some contributions were solicited to give a more complete overview of `The Early History of European Radio Astronomy'.

  17. Radio astronomy on the moon

    International Nuclear Information System (INIS)

    Burns, J.O.; Asbell, J.

    1987-01-01

    The advantages and opportunities for radio astronomy on the moon during the early to mid 21st century are reviewed. In particular, it is argued that the lack of atmosphere, the extremely low seismic activity, the low RF background, and the natural cryogenic environment make the moon (particularly the far side and the poles) a nearly ideal locale for submillimeter/FIR to VLF (below 10 MHz) radio astronomy. 22 references

  18. Bibliometric evaluation of Finnish astronomy

    OpenAIRE

    Isaksson, Eva

    2007-01-01

    Finnish astronomy publishing provides us with an interesting data sample. It is small but not too small: approximately one thousand articles have been published in a decade. There are only four astronomy institutes to be compared. An interesting paradox also emerges in the field: while Finnish science assessments usually value highly the impact of scientific publishing, no serious evaluations using real bibliometric data have been made. To remedy this, a comprehensive ten-year database of ref...

  19. News clippings for introductory astronomy

    Science.gov (United States)

    Bobrowsky, Matthew

    1999-09-01

    Most students entering our introductory astronomy course for nonscience majors arrive not merely lacking scientific facts-they also have misconceptions about the nature of science, and many have a handicapping ``science anxiety'' (in addition to math anxiety). So I have added a ``current science'' requirement to our introductory course. Each student must compile a file of five astronomy news articles taken from readily available sources.

  20. Receiving recommendations and providing feedback : the user-experience of a recommender system

    NARCIS (Netherlands)

    Knijnenburg, B.P.; Willemsen, M.C.; Hirtbach, S.; Buccafurri, F.; Semeraro, G.

    2010-01-01

    This paper systematically evaluates the user experience of a recommender system. Using both behavioral data and subjective measures of user experience, we demonstrate that choice satisfaction and system effectiveness increase when a system provides personalized recommendations (compared to the same

  1. Music and Astronomy Under the Stars - 2009 Update

    Science.gov (United States)

    Lubowich, Donald A.

    2010-01-01

    Bring telescope to where the people are! Music and Astronomy Under the Stars is a three-year NASA-funded outreach program at parks during and after concerts and family events - a Halloween Spooky Garden Walk. While there have been many outreach activities and telescope observations at city sidewalks and parks, this program targets a completely different audience - music lovers who attend summer concerts held in community parks. These music lovers who may never have visited a science museum, planetarium, or star party are exposed to telescope observations and astronomy information with no additional travel costs. Music and Astronomy Under the Stars increased awareness, engagement, and interest in astronomy at classical, pop, rock, and ethnic music concerts. This program includes solar observing before the concerts, telescope observations including a live image projection system, an astronomical video presentation, and astronomy banners/posters. Approximately 500 - 16,000 people attended each event and 25% to 50% of the people at each event participated in the astronomy program. This program also reached underrepresented and underserved groups (women, minorities, older adults). The target audience is 2,900,000 people, which is larger than combined population of Atlanta, Boston, Denver, Minneapolis, and San Francisco. Although eleven events were planned in 2009, two were canceled due to rain and our largest event, the NY Philharmonic in the Park (attended by 67,000 people in 2008), was cancelled for financial reasons. Our largest event in 2009 was the Tanglewood Music Festival, Lenox MA, attended by 16,000 people where 5000 people participated in astronomy activities. The Amateur Observers' Society of NY assisted with the NY concerts and the Springfield STARS club assisted at Tanglewood. 1500 people looked through telescopes at the Halloween program (6000 saw the posters). In 2009 over 15,000 people participated in these astronomy activities which were attended by

  2. Astronomy in Primary and Secondary Education in Slovenia

    Science.gov (United States)

    Gomboc, Andreja

    2015-08-01

    I will present the status of astronomy in educational system in Slovenia. In primary schools astronomy is offered as an optional course in the last 3 grades (12-15 yrs old), while in secondary schools a few astronomical topics are present only as part of other subjects (e.g. physics, geography). I will describe a pilot project of an astronomy course in secondary schools, which was carried out in the school year 2013/14. The main focus of my presentation will be the experience gained with organisation of the Slovenian National Astronomy Competition. It is organised by the Slovenian Society of Mathematicians, Physicists and Astronomers since 2009, building on an extensive network of over 200 primary and secondary school teachers who participated in IYA2009 activities, and who now represent majority of mentors for the competition. In 2013, only 5 years after the start of competition, our pupils attended the International Olympiad on Astronomy and Astrophysics for the first time and with great success. Supporting activities include the Slovenian version of the Portal to the Universe (www.portalvvesolje.si) and translation of Space Scoop astronomy news for children.

  3. Astronomy at the Market

    Science.gov (United States)

    Roten, Robert; Constantin, A.; Christensen, E.; Dick, E.; Lapolla, J.; Nutter, A.; Corcoran, J.; DiDomenico, N.; Eskridge, B.; Saikin, A.

    2014-01-01

    We present here an energetic grass-roots outreach program run entirely by undergraduate physics and astronomy majors at James Madison University. Our "Team Awestronomy" takes Astronomy out to the Market, literally. Once a month, for eight months during the academic year, the group sets up a “scientific corner” at the Harrisonburg Farmers Market, offering people the chance to meet with astrophysicists (in the making) and discuss science. Our group members wear t-shirts with simple messages like “Ask me about the Sun,” “...about Black Holes and Mega-Masers” or “...about Big Bang” that initiate the dialog. We help our audience with observations of solar activity through our department’s Coronado telescope equipped with a safe H-alpha filter, sunspotters, and the incredibly simple yet durable and accurate handheld (Project Star) spectrometers, and invite them to the free Saturday Planetarium shows and the star parties hosted by our department on the JMU campus. The team is also prepared with a suite of fun activities aimed particularly at K-5 kids, e.g., building (and eating, after investigating out-gassing properties of) ”dirty comets,” making craters (in pans with flour or sand) and testing how different types of impactors (pebbles, ping-pong balls or even crumpled aluminum foil) affect crater formation, and demonstrations of shock wave created in supernova explosions. The main goals of this outreach program are: 1) to illustrate to people of all ages that science is a fun, creative, and exciting process; 2) to empower people to be curious and to ask questions; 3) to demonstrate that science is a viable career path chosen by many diverse individuals; and 4) to nurture a sense of wonder and awe for the Universe. While this outreach program is aimed at a very general audience, of an extremely wide range, we expect to produce a significant impact on K-12 students in general and in particular on the home-schooled kids. There is a relatively high

  4. Intelligent Cognitive Radio Models for Enhancing Future Radio Astronomy Observations

    Directory of Open Access Journals (Sweden)

    Ayodele Abiola Periola

    2016-01-01

    Full Text Available Radio astronomy organisations desire to optimise the terrestrial radio astronomy observations by mitigating against interference and enhancing angular resolution. Ground telescopes (GTs experience interference from intersatellite links (ISLs. Astronomy source radio signals received by GTs are analysed at the high performance computing (HPC infrastructure. Furthermore, observation limitation conditions prevent GTs from conducting radio astronomy observations all the time, thereby causing low HPC utilisation. This paper proposes mechanisms that protect GTs from ISL interference without permanent prevention of ISL data transmission and enhance angular resolution. The ISL transmits data by taking advantage of similarities in the sequence of observed astronomy sources to increase ISL connection duration. In addition, the paper proposes a mechanism that enhances angular resolution by using reconfigurable earth stations. Furthermore, the paper presents the opportunistic computing scheme (OCS to enhance HPC utilisation. OCS enables the underutilised HPC to be used to train learning algorithms of a cognitive base station. The performances of the three mechanisms are evaluated. Simulations show that the proposed mechanisms protect GTs from ISL interference, enhance angular resolution, and improve HPC utilisation.

  5. Astronomy Research Seminar

    Science.gov (United States)

    Johson, Jolyon; Genet, Russell; Armstrong, James; Boyce, Grady; Boyce, Pat; Brewer, Mark; Buchheim, Robert; Carro, Joseph; Estrada, Reed; Estrada, Chris; Freed, Rachel; Gillette, Sean; Harshaw, Richard; Hollis, Thomas; Kenney, John; McGaughey, Seven; McNab, Christine; Mohanan, Kakkala; Sepulveda, Babs; Wallace, Dan; Wallen, Vera

    2015-05-01

    Traditional science lectures and labs are often enhanced through project- and team-based learning. Some students go beyond these classroom studies by conducting research, often under the guidance of university professors. A one-semester astronomy research seminar was initiated in 2006 in collaboration with the community of professional and amateur double star astronomers. The result was dozens of jointly-authored papers published in the Journal of Double Star Observations and the Annual Proceedings of the Society of Astronomical Sciences. This seminar, and its affiliated community, launched a series of conferences and books, providing students with additional forums to share their double star research. The original seminar, and its derivatives, enhanced educational careers through college admissions and scholarships. To expand the seminar's reach, it was restructured from a few teams at one school, to many teams, each from a different school. A volunteer from each school became an assistant instructor. Most of them were seminar veterans, experienced astronomers, or science teachers. The assistant instructors, in turn, recruited enthusiastic students for their teams. To avoid student and instructor overload, the seminar focused on its three deliverables: a formal proposal, published paper, and public PowerPoint presentation. Future seminars may offer other astronomical research options such as exoplanet transit or eclipsing binary photometry.

  6. Stellar extreme ultraviolet astronomy

    International Nuclear Information System (INIS)

    Cash, W.C. Jr.

    1978-01-01

    The design, calibration, and launch of a rocket-borne imaging telescope for extreme ultraviolet astronomy are described. The telescope, which employed diamond-turned grazing incidence optics and a ranicon detector, was launched November 19, 1976, from the White Sands Missile Range. The telescope performed well and returned data on several potential stellar sources of extreme ultraviolet radiation. Upper limits ten to twenty times more sensitive than previously available were obtained for the extreme ultraviolet flux from the white dwarf Sirius B. These limits fall a factor of seven below the flux predicted for the star and demonstrate that the temperature of Sirius B is not 32,000 K as previously measured, but is below 30,000 K. The new upper limits also rule out the photosphere of the white dwarf as the source of the recently reported soft x-rays from Sirius. Two other white dwarf stars, Feige 24 and G191-B2B, were observed. Upper limits on the flux at 300 A were interpreted as lower limits on the interstellar hydrogen column densities to these stars. The lower limits indicate interstellar hydrogen densitites of greater than .02 cm -3 . Four nearby stars (Sirius, Procyon, Capella, and Mirzam) were observed in a search for intense low temperature coronae or extended chromospheres. No extreme ultraviolet radiation from these stars was detected, and upper limits to their coronal emisson measures are derived

  7. Astronomy and Atmospheric Optics

    Science.gov (United States)

    Cowley, Les; Gaina, Alex

    2011-12-01

    The authors discusse the insuccess of the observation of the Total Eclipse of the Moon from 10 december 2011 in Romania and relate them with meteoconditions. Only a very short part of the last penumbral phase was observed, while the inital part and the totality was not observed due to very dense clouds. The change in color and brightness during this phase was signaled. Meanwhile, there is an area of science where clouds are of great use and interest. This area is Atmospheric optics, while the science which study clouds is meteorology. Clouds in combination with Solar and Moon light could give rise to a variety of strange, rare and unobvious phenomena in the atmosphere (sky), sometimes confused with Unidentified Flying Objects (UFO). The importance of meteorology for astronomy and atmospheric optics is underlined and an invitation to astronomers to use unfavourable days for athmospheric observations was sent. The web address of the site by Les Cowley, designed for atmospheric optics phenomena is contained in the text of the entry.

  8. Grab 'n' go astronomy

    CERN Document Server

    English, Neil

    2014-01-01

      Like everyone else, most amateur astronomers live busy lives. After a long day, the last thing you want as an observer is to have to lug out a large telescope and spend an hour getting it ready before it can be used. Maybe you are going somewhere sure to have dark skies, but you don’t necessarily want astronomy to dominate the trip. Or you are not quite committed to owning a large telescope, but curious enough to see what a smaller, portable setup can accomplish. These are times when a small “grab ’n’ go” telescope, or even a pair of binoculars, is the ideal in­strument. And this book can guide you in choosing and best utilizing that equipment.   What makes a telescope fall into the “grab ’n’ go” category? That’s easy – speed of setting up, ease of use, and above all, portability. This ambitious text is dedicated to those who love to or – because of their limited time – must observe the sky at a moment’s notice. Whether observing from the comfort of a backyard or while on busi...

  9. System performance of a 4-channel PHASAR WDM receiver operating at 1.2 Gbit/s

    NARCIS (Netherlands)

    Steenbergen, C.A.M.; van Deventer, M.O.; Vreede, de L.C.N.; Dam, van C.; Smit, M.K.; Verbeek, B.H.

    1996-01-01

    Phased arrays are important key components in wavelength-division multiplexing (WDM) systems. We have realized a 4-channel WDM receiver combining a phased array with photodetectors on InP with a Si bipolar transimpedance amplifier. The channels are spaced at 2.0 nm with a 1.0-nm flat passband. On

  10. Long-range high-speed visible light communication system over 100-m outdoor transmission utilizing receiver diversity technology

    Science.gov (United States)

    Wang, Yiguang; Huang, Xingxing; Shi, Jianyang; Wang, Yuan-quan; Chi, Nan

    2016-05-01

    Visible light communication (VLC) has no doubt become a promising candidate for future wireless communications due to the increasing trends in the usage of light-emitting diodes (LEDs). In addition to indoor high-speed wireless access and positioning applications, VLC usage in outdoor scenarios, such as vehicle networks and intelligent transportation systems, are also attracting significant interest. However, the complex outdoor environment and ambient noise are the key challenges for long-range high-speed VLC outdoor applications. To improve system performance and transmission distance, we propose to use receiver diversity technology in an outdoor VLC system. Maximal ratio combining-based receiver diversity technology is utilized in two receivers to achieve the maximal signal-to-noise ratio. A 400-Mb/s VLC transmission using a phosphor-based white LED and a 1-Gb/s wavelength division multiplexing VLC transmission using a red-green-blue LED are both successfully achieved over a 100-m outdoor distance with the bit error rate below the 7% forward error correction limit of 3.8×10-3. To the best of our knowledge, this is the highest data rate at 100-m outdoor VLC transmission ever achieved. The experimental results clearly prove the benefit and feasibility of receiver diversity technology for long-range high-speed outdoor VLC systems.

  11. Effects of prasterone on bone mineral density in women with active systemic lupus erythematosus receiving chronic glucocorticoid therapy.

    Science.gov (United States)

    Sánchez-Guerrero, Jorge; Fragoso-Loyo, Hilda E; Neuwelt, C Michael; Wallace, Daniel J; Ginzler, Ellen M; Sherrer, Yvonne R S; McIlwain, Harris H; Freeman, Pamela G; Aranow, Cynthia; Petri, Michelle A; Deodhar, Atul A; Blanton, Ellen; Manzi, Susan; Kavanaugh, Arthur; Lisse, Jeffrey R; Ramsey-Goldman, Rosalind; McKay, James D; Kivitz, Alan J; Mease, Philip J; Winkler, Anne E; Kahl, Leslie E; Lee, Albert H; Furie, Richard A; Strand, C Vibeke; Lou, Lillian; Ahmed, Mumtaz; Quarles, Betty; Schwartz, Kenneth E

    2008-08-01

    To assess prevention of bone mineral density (BMD) loss and durability of the response during treatment with prasterone in women with systemic lupus erythematosus (SLE) receiving chronic glucocorticoids. 155 patients with SLE received 200 mg/day prasterone or placebo for 6 months in a double-blind phase. Subsequently, 114 patients were re-randomized to receive 200 or 100 mg/day prasterone for 12 months in an open-label phase. Primary efficacy endpoints were changes in BMD at the lumbar spine (L-spine) from baseline to Month 6 and maintenance of BMD from Month 6 to 18 for patients who received prasterone during the double-blind phase. In the double-blind phase, there was a trend for a small gain in BMD at the L-spine for patients who received 200 mg/day prasterone for 6 months versus a loss in the placebo group (mean +/- SD, 0.003 +/- 0.035 vs -0.005 +/- 0.053 g/cm(2), respectively; p = 0.293 between groups). In the open-label phase, there was dose-dependent increase in BMD at the L-spine at Month 18 between patients who received 200 versus 100 mg/day prasterone (p = 0.021). For patients who received 200 mg/day prasterone for 18 months, the L-spine BMD gain was 1.083 +/- 0.512% (p = 0.042). There was no overall change in BMD at the total hip over 18 months with 200 mg/day prasterone treatment. The safety profile reflected the weak androgenic properties of prasterone. This study suggests prasterone 200 mg/day may offer mild protection against bone loss in women with SLE receiving glucocorticoids. (ClinicalTrials.gov Identifiers NCT00053560 and NCT00082511).

  12. Consumers’ intention to use health recommendation systems to receive personalized nutrition advice

    NARCIS (Netherlands)

    S. Wendel (Sonja); B.G.C. Dellaert (Benedict); A. Ronteltap (Amber); H.C.M. van Trijp (Hans)

    2013-01-01

    markdownabstract__Abstract__ __Background:__ Sophisticated recommendation systems are used more and more in the health sector to assist consumers in healthy decision making. In this study we investigate consumers' evaluation of hypothetical health recommendation systems that provide

  13. Consumers’ intention to use health recommendation systems to receive personalized nutrition advice

    NARCIS (Netherlands)

    Wendel, S.; Dellaert, B.G.C.; Ronteltap, A.; Trijp, van J.C.M.

    2013-01-01

    Background: Sophisticated recommendation systems are used more and more in the health sector to assist consumers in healthy decision making. In this study we investigate consumers' evaluation of hypothetical health recommendation systems that provide personalized nutrition advice. We examine

  14. Consumers' intention to use health recommendation systems to receive personalized nutrition advice

    NARCIS (Netherlands)

    S. Wendel (Sonja); B.G.C. Dellaert (Benedict); A. Ronteltap (Amber); H.C.M. van Trijp (Hans)

    2013-01-01

    textabstractBackground: Sophisticated recommendation systems are used more and more in the health sector to assist consumers in healthy decision making. In this study we investigate consumers' evaluation of hypothetical health recommendation systems that provide personalized nutrition advice. We

  15. Brian M. Kleiner receives Ralph H. Bogle Professor Fellowship in Industrial and Systems Engineering

    OpenAIRE

    Owczarski, Mark

    2010-01-01

    Brian M. Kleiner, professor of industrial and systems engineering in the College of Engineering at Virginia Tech, has been named the Ralph H. Bogle Professor Fellow in Industrial and Systems Engineering by the Virginia Tech Board of Visitors.

  16. Real-time validation of receiver state information in optical space-time block code systems.

    Science.gov (United States)

    Alamia, John; Kurzweg, Timothy

    2014-06-15

    Free space optical interconnect (FSOI) systems are a promising solution to interconnect bottlenecks in high-speed systems. To overcome some sources of diminished FSOI performance caused by close proximity of multiple optical channels, multiple-input multiple-output (MIMO) systems implementing encoding schemes such as space-time block coding (STBC) have been developed. These schemes utilize information pertaining to the optical channel to reconstruct transmitted data. The STBC system is dependent on accurate channel state information (CSI) for optimal system performance. As a result of dynamic changes in optical channels, a system in operation will need to have updated CSI. Therefore, validation of the CSI during operation is a necessary tool to ensure FSOI systems operate efficiently. In this Letter, we demonstrate a method of validating CSI, in real time, through the use of moving averages of the maximum likelihood decoder data, and its capacity to predict the bit error rate (BER) of the system.

  17. Inverse spiking filter based acquisition enhancement in software based global positioning system receiver

    Directory of Open Access Journals (Sweden)

    G. Arul Elango

    2015-01-01

    Full Text Available The lower visibility of the satellite in the acquisition stage of a GPS receiver under worst noisy situation leads to reacquisition of the data and thereby takes a longer time to obtain the first position fix. If the impulse noise affects the GPS signal, the conventional ways of acquiring the satellites do not guarantee to meet the minimum requirement of four satellites to find the user position. The performance of GPS receiver acquisition can be improved in the low SNR level using inverse spiking filtering technique. In the proposed method, the estimate of the desired GPS L1 signal corrupted by impulse noise (gn is obtained by the prediction error filter (hopt, which is the optimum inverse filter that reshapes the noisy signal (yn into a desired GPS signal (xn. In the proposed method, to detect the visible satellites under weak signal conditions the traditional differential coherent approach is combined with the inverse spiking filter method to increase the number of visible satellites and to avoid the reacquisition process. Montecarlo simulation is carried out to assess the performance of the proposed method for C/N0 of 20 dB-Hz and results indicate that the modified differential coherent method effectively excises the noise with 90% probability of detection. Subsequently tracking operation is also tested to confirm the acquisition performance by demodulating the navigation data successfully.

  18. A Novel Mirror-Aided Non-imaging Receiver for Indoor 2x2 MIMO Visible Light Communication Systems

    KAUST Repository

    Park, Kihong

    2017-06-07

    Indoor visible light communication (VLC) systems are now possible because of advances in light emitting diode and laser diode technologies. These lighting technologies provide the foundation for multiple-input multiple-output (MIMO) data transmission through visible light. However, the channel matrix can be strongly correlated in indoor MIMO-VLC systems, preventing parallel data streams from being decoded. Here, in $2\\\\times 2$ MIMO-VLC systems, we describe a mirror diversity receiver (MDR) design that reduces the channel correlation by both blocking the reception of light from one specific direction and improving the channel gain from light from another direction by utilizing a double-sided mirror deployed between the receiver\\'s photodetectors. We report on the channel capacity of the MDR system and the optimal height of its mirrors in terms of maximum channel capacity. We also derived analytic results on the effect of rotation on MDR\\'s performance. Based on numerical and experimental results, we show that the double-sided mirror has both constructive and destructive effects on the channel matrix. Our design can be used with previously described non-imaging systems to improve the performance of indoor VLC systems.

  19. Astronomy Village Reaches for New Heights

    Science.gov (United States)

    Croft, S. K.; Pompea, S. M.

    2007-12-01

    We are developing a set of complex, multimedia-based instructional modules emphasizing technical and scientific issues related to Giant Segmented Mirror Telescope project. The modules" pedagogy will be open-ended and problem-based to promote development of problem-solving skills. Problem- based-learning modules that emphasize work on open-ended complex real world problems are particularly valuable in illustrating and promoting a perspective on the process of science and engineering. Research in this area shows that these kinds of learning experiences are superior to more conventional student training in terms of gains in student learning. The format for the modules will be based on the award-winning multi-media educational Astronomy Village products that present students with a simulated environment: a mountaintop community surrounded by a cluster of telescopes, satellite receivers, and telecommunication towers. A number of "buildings" are found in the Village, such as a library, a laboratory, and an auditorium. Each building contains an array of information sources and computer simulations. Students navigate through their research with a mentor via imbedded video. The first module will be "Observatory Site Selection." Students will use astronomical data, basic weather information, and sky brightness data to select the best site for an observatory. Students will investigate the six GSMT sites considered by the professional site selection teams. Students will explore weather and basic site issues (e.g., roads and topography) using remote sensing images, computational fluid dynamics results, turbulence profiles, and scintillation of the different sites. Comparison of student problem solving with expert problem solving will also be done as part of the module. As part of a site selection team they will have to construct a case and present it on why they chose a particular site. The second module will address aspects of system engineering and optimization for a GSMT

  20. A Grand Vision for European Astronomy

    Science.gov (United States)

    2007-09-01

    Today, and for the first time, astronomers share their global Science Vision for European Astronomy in the next two decades. This two-year long effort by the ASTRONET network of funding agencies, sponsored by the European Commission and coordinated by INSU-CNRS, underscores Europe's ascension to world leadership in astronomy and its will to maintain that position. It will be followed in just over a year by a prioritised roadmap for the observational facilities needed to implement the Vision. Implementation of these plans will ensure that Europe fully contributes to Mankind's ever deeper understanding of the wonders of our Universe. astronet logo "This is a great opportunity to help create a vibrant long-term future for astronomy and science" says Tim de Zeeuw (Leiden Observatory, The Netherlands) who led this community-wide effort. The ASTRONET Science Vision provides a comprehensive overview of the most important scientific questions that European astronomy should address in the next twenty years. The four key questions are the extremes of the Universe, from the nature of the dark matter and dark energy that comprise over 95% of the Universe to the physics of extreme objects such as black holes, neutron stars, and gamma-ray bursts; the formation of galaxies from the first seeds to our Milky Way; the formation of stars and planets and the origin of life; and the crucial question of how do we (and our Solar System) fit in the global picture. These themes reach well beyond the realm of traditional astronomy into the frontiers of physics and biology. The Vision identifies the major new facilities that will be needed to achieve these goals, but also stresses the need for parallel developments in theory and numerical simulations, high-performance computing resources, efficient astronomical data archiving and the European Virtual Observatory, as well as in laboratory astrophysics. "This report is a key input for the even more challenging task of developing a prioritised

  1. Optical timing receiver for the NASA Spaceborne Ranging System. Part II: high precision event-timing digitizer

    Energy Technology Data Exchange (ETDEWEB)

    Leskovar, Branko; Turko, Bojan

    1978-08-01

    Position-resolution capabilities of the NASA Spaceborne Laser Ranging System are essentially determined by the timeresolution capabilities of its optical timing receiver. The optical timing receiver consists of a fast photoelectric device; (e.g., photomultiplier or an avalanche photodiode detector), a timing discriminator, a high-precision event-timing digitizer, and a signal-processing system. The time-resolution capabilities of the receiver are determined by the photoelectron time spread of the photoelectric device, the time walk and resolution characteristics of the timing discriminator, and the resolution of the event-timing digitizer. It is thus necessary to evaluate available fast photoelectronic devices with respect to the time-resolution capabilities, and to develop a very low time walk timing discriminator and a high-resolution event-timing digitizer to be used in the high-resolution spaceborne laser ranging system receiver. This part of the report describes the development of a high precision event-timing digitizer. The event-timing digitizer is basically a combination of a very accurate high resolution real time digital clock and an interval timer. The timing digitizer is a high resolution multiple stop clock, counting the time up to 131 days in 19.5 ps increments.

  2. Consumers’ intention to use health recommendation systems to receive personalized nutrition advice

    Science.gov (United States)

    2013-01-01

    Background Sophisticated recommendation systems are used more and more in the health sector to assist consumers in healthy decision making. In this study we investigate consumers' evaluation of hypothetical health recommendation systems that provide personalized nutrition advice. We examine consumers' intention to use such a health recommendation system as a function of options related to the underlying system (e.g. the type of company that generates the advice) as well as intermediaries (e.g. general practitioner) that might assist in using the system. We further explore if the effect of both the system and intermediaries on intention to use a health recommendation system are mediated by consumers' perceived effort, privacy risk, usefulness and enjoyment. Methods 204 respondents from a consumer panel in the Netherlands participated. The data were collected by means of a questionnaire. Each respondent evaluated three hypothetical health recommendation systems on validated multi-scale measures of effort, privacy risk, usefulness, enjoyment and intention to use the system. To test the hypothesized relationships we used regression analyses. Results We find evidence that the options related to the underlying system as well as the intermediaries involved influence consumers' intention to use such a health recommendation system and that these effects are mediated by perceptions of effort, privacy risk, usefulness and enjoyment. Also, we find that consumers value usefulness of a system more and enjoyment less when a general practitioner advices them to use a health recommendation system than if they use it out of their own curiosity. Conclusions We developed and tested a model of consumers' intention to use a health recommendation system. We found that intermediaries play an important role in how consumers evaluate such a system over and above options of the underlying system that is used to generate the recommendation. Also, health-related information services seem to

  3. Consumers' intention to use health recommendation systems to receive personalized nutrition advice.

    Science.gov (United States)

    Wendel, Sonja; Dellaert, Benedict G C; Ronteltap, Amber; van Trijp, Hans C M

    2013-04-04

    Sophisticated recommendation systems are used more and more in the health sector to assist consumers in healthy decision making. In this study we investigate consumers' evaluation of hypothetical health recommendation systems that provide personalized nutrition advice. We examine consumers' intention to use such a health recommendation system as a function of options related to the underlying system (e.g. the type of company that generates the advice) as well as intermediaries (e.g. general practitioner) that might assist in using the system. We further explore if the effect of both the system and intermediaries on intention to use a health recommendation system are mediated by consumers' perceived effort, privacy risk, usefulness and enjoyment. 204 respondents from a consumer panel in the Netherlands participated. The data were collected by means of a questionnaire. Each respondent evaluated three hypothetical health recommendation systems on validated multi-scale measures of effort, privacy risk, usefulness, enjoyment and intention to use the system. To test the hypothesized relationships we used regression analyses. We find evidence that the options related to the underlying system as well as the intermediaries involved influence consumers' intention to use such a health recommendation system and that these effects are mediated by perceptions of effort, privacy risk, usefulness and enjoyment. Also, we find that consumers value usefulness of a system more and enjoyment less when a general practitioner advices them to use a health recommendation system than if they use it out of their own curiosity. We developed and tested a model of consumers' intention to use a health recommendation system. We found that intermediaries play an important role in how consumers evaluate such a system over and above options of the underlying system that is used to generate the recommendation. Also, health-related information services seem to rely on endorsement by the medical sector

  4. A high temperature superconductor tape RF receiver coil for a low field magnetic resonance imaging system

    International Nuclear Information System (INIS)

    Cheng, M C; Yan, B P; Lee, K H; Ma, Q Y; Yang, E S

    2005-01-01

    High temperature superconductor (HTS) thin films have been applied in making a low loss RF receiver coil for improving magnetic resonance imaging image quality. However, the application of these coils is severely limited by their limited field of view (FOV). Stringent fabrication environment requirements and high cost are further limitations. In this paper, we propose a simpler method for designing and fabricating HTS coils. Using industrial silver alloy sheathed Bi (2-x) Pb x Sr 2 Ca 2 Cu 3 O 10 (Bi-2223) HTS tapes, a five-inch single-turn HTS solenoid coil has been developed, and human wrist images have been acquired with this coil. The HTS tape coil has demonstrated an enhanced FOV over a six-inch YBCO thin film surface coil at 77 K with comparable signal-to-noise ratio

  5. Adaptive Nonlinear RF Cancellation for Improved Isolation in Simultaneous Transmit–Receive Systems

    Science.gov (United States)

    Kiayani, Adnan; Waheed, Muhammad Zeeshan; Anttila, Lauri; Abdelaziz, Mahmoud; Korpi, Dani; Syrjala, Ville; Kosunen, Marko; Stadius, Kari; Ryynanen, Jussi; Valkama, Mikko

    2018-05-01

    This paper proposes an active radio frequency (RF) cancellation solution to suppress the transmitter (TX) passband leakage signal in radio transceivers supporting simultaneous transmission and reception. The proposed technique is based on creating an opposite-phase baseband equivalent replica of the TX leakage signal in the transceiver digital front-end through adaptive nonlinear filtering of the known transmit data, to facilitate highly accurate cancellation under a nonlinear TX power amplifier (PA). The active RF cancellation is then accomplished by employing an auxiliary transmitter chain, to generate the actual RF cancellation signal, and combining it with the received signal at the receiver (RX) low noise amplifier (LNA) input. A closed-loop parameter learning approach, based on the decorrelation principle, is also developed to efficiently estimate the coefficients of the nonlinear cancellation filter in the presence of a nonlinear TX PA with memory, finite passive isolation, and a nonlinear RX LNA. The performance of the proposed cancellation technique is evaluated through comprehensive RF measurements adopting commercial LTE-Advanced transceiver hardware components. The results show that the proposed technique can provide an additional suppression of up to 54 dB for the TX passband leakage signal at the RX LNA input, even at considerably high transmit power levels and with wide transmission bandwidths. Such novel cancellation solution can therefore substantially improve the TX-RX isolation, hence reducing the requirements on passive isolation and RF component linearity, as well as increasing the efficiency and flexibility of the RF spectrum use in the emerging 5G radio networks.

  6. Combined cycle solar central receiver hybrid power system study. Volume III. Appendices. Final technical report

    Energy Technology Data Exchange (ETDEWEB)

    None

    1979-11-01

    A design study for a 100 MW gas turbine/steam turbine combined cycle solar/fossil-fuel hybrid power plant is presented. This volume contains the appendices: (a) preconceptual design data; (b) market potential analysis methodology; (c) parametric analysis methodology; (d) EPGS systems description; (e) commercial-scale solar hybrid power system assessment; and (f) conceptual design data lists. (WHK)

  7. Abundance and fate of antibiotics and hormones in a vegetative treatment system receiving cattle feedlot runoff

    Science.gov (United States)

    Vegetative treatment systems (VTS) have been developed and built as an alternative to conventional holding pond systems for managing run-off from animal feeding operations. Initially developed to manage runoff nutrients via uptake by grasses, their effectiveness at removing other runoff contaminant...

  8. Diversity receiver

    NARCIS (Netherlands)

    2005-01-01

    The invention is directed to the reception of high rate radio signals (for example DVB-T signals) while the receiver is moving at a high speed (for example in or with a car). Two or more antennas (12, 16) are closely spaced and arranged behind each other in the direction of motion (v) for receiving

  9. Central Receiver Solar Thermal Power System, Phase 1. CDRL Item 2. Pilot Plant preliminary design report. Volume III, Book 1. Collector subsystem

    Energy Technology Data Exchange (ETDEWEB)

    Hallet, Jr., R. W.; Gervais, R. L.

    1977-10-01

    The central receiver system consists of a field of heliostats, a central receiver, a thermal storage unit, an electrical power generation system, and balance of plant. This volume discusses the collector field geometry, requirements and configuration. The development of the collector system and subsystems are discussed and the selection rationale outlined. System safety and availability are covered. Finally, the plans for collector portion of the central receiver system are reviewed.

  10. A Community - Centered Astronomy Research Program

    Science.gov (United States)

    Boyce, Pat; Boyce, Grady

    2017-06-01

    The Boyce Research Initiatives and Education Foundation (BRIEF) is providing semester-long, hands-on, astronomy research experiences for students of all ages that results in their publishing peer-reviewed papers. The course in astronomy and double star research has evolved from a face-to-face learning experience with two instructors to an online - hybrid course that simultaneously supports classroom instruction at a variety of schools in the San Diego area. Currently, there are over 65 students enrolled in three community colleges, seven high schools, and one university as well as individual adult learners. Instructional experience, courseware, and supporting systems were developed and refined through experience gained in classroom settings from 2014 through 2016. Topics of instruction include Kepler's Laws, basic astrometry, properties of light, CCD imaging, use of filters for varying stellar spectral types, and how to perform research, scientific writing, and proposal preparation. Volunteer instructors were trained by taking the course and producing their own research papers. An expanded program was launched in the fall semester of 2016. Twelve papers from seven schools were produced; eight have been accepted for publication by the Journal of Double Observations (JDSO) and the remainder are in peer review. Three additional papers have been accepted by the JDSO and two more are in process papers. Three college professors and five advanced amateur astronomers are now qualified volunteer instructors. Supporting tools are provided by a BRIEF server and other online services. The server-based tools range from Microsoft Office and planetarium software to top-notch imaging programs and computational software for data reduction for each student team. Observations are performed by robotic telescopes worldwide supported by BRIEF. With this success, student demand has increased significantly. Many of the graduates of the first semester course wanted to expand their

  11. Performance analysis of underlay cognitive multihop regenerative relaying systems with multiple primary receivers

    KAUST Repository

    Hyadi, Amal; Benjillali, Mustapha; Alouini, Mohamed-Slim; Da Costa, Daniel Benevides Da

    2013-01-01

    Multihop relaying is an efficient strategy to improve the connectivity and extend the coverage area of secondary networks in underlay cognitive systems. In this work, we provide a comprehensive performance study of cognitive multihop regenerative

  12. W-026, Waste Receiving and Processing Facility data management system validation and verification report

    International Nuclear Information System (INIS)

    Palmer, M.E.

    1997-01-01

    This V and V Report includes analysis of two revisions of the DMS [data management system] System Requirements Specification (SRS) and the Preliminary System Design Document (PSDD); the source code for the DMS Communication Module (DMSCOM) messages; the source code for selected DMS Screens, and the code for the BWAS Simulator. BDM Federal analysts used a series of matrices to: compare the requirements in the System Requirements Specification (SRS) to the specifications found in the System Design Document (SDD), to ensure the design supports the business functions, compare the discreet parts of the SDD with each other, to ensure that the design is consistent and cohesive, compare the source code of the DMS Communication Module with the specifications, to ensure that the resultant messages will support the design, compare the source code of selected screens to the specifications to ensure that resultant system screens will support the design, compare the source code of the BWAS simulator with the requirements to interface with DMS messages and data transfers relating to the BWAS operations

  13. W-026, Waste Receiving and Processing Facility data management system validation and verification report

    Energy Technology Data Exchange (ETDEWEB)

    Palmer, M.E.

    1997-12-05

    This V and V Report includes analysis of two revisions of the DMS [data management system] System Requirements Specification (SRS) and the Preliminary System Design Document (PSDD); the source code for the DMS Communication Module (DMSCOM) messages; the source code for selected DMS Screens, and the code for the BWAS Simulator. BDM Federal analysts used a series of matrices to: compare the requirements in the System Requirements Specification (SRS) to the specifications found in the System Design Document (SDD), to ensure the design supports the business functions, compare the discreet parts of the SDD with each other, to ensure that the design is consistent and cohesive, compare the source code of the DMS Communication Module with the specifications, to ensure that the resultant messages will support the design, compare the source code of selected screens to the specifications to ensure that resultant system screens will support the design, compare the source code of the BWAS simulator with the requirements to interface with DMS messages and data transfers relating to the BWAS operations.

  14. Nitrogen removal and nitrate leaching for two perennial, sod-based forage systems receiving dairy effluent.

    Science.gov (United States)

    Woodard, Kenneth R; French, Edwin C; Sweat, Lewin A; Graetz, Donald A; Sollenberger, Lynn E; Macoon, Bisoondat; Portier, Kenneth M; Rymph, Stuart J; Wade, Brett L; Prine, Gordon M; Van Horn, Harold H

    2003-01-01

    In northern Florida, year-round forage systems are used in dairy effluent sprayfields to reduce nitrate leaching. Our purpose was to quantify forage N removal and monitor nitrate N (NO3(-)-N) concentration below the rooting zone for two perennial, sod-based, triple-cropping systems over four 12-mo cycles (1996-2000). The soil is an excessively drained Kershaw sand (thermic, uncoated Typic Quartzip-samment). Effluent N rates were 500, 690, and 910 kg ha(-1) per cycle. Differences in N removal between a corn (Zea mays L.)-bermudagrass (Cynodon spp.)-rye (Secale cereale L.) system (CBR) and corn-perennial peanut (Arachis glabrata Benth.)-rye system (CPR) were primarily related to the performance of the perennial forages. Nitrogen removal of corn (125-170 kg ha(-1)) and rye (62-90 kg ha(-1)) was relatively stable between systems and among cycles. The greatest N removal was measured for CBR in the first cycle (408 kg ha(-1)), with the bermudagrass removing an average of 191 kg N ha(-1). In later cycles, N removal for bermudagrass declined because dry matter (DM) yield declined. Yield and N removal of perennial peanut increased over the four cycles. Nitrate N concentrations below the rooting zone were lower for CBR than CPR in the first two cycles, but differences were inconsistent in the latter two. The CBR system maintained low NO3(-)-N leaching in the first cycle when the bermudagrass was the most productive; however, it was not a sustainable system for long-term prevention of NO3(-)-N leaching due to declining bermudagrass yield in subsequent cycles. For CPR, effluent N rates > or = 500 kg ha(-1) yr(-1) have the potential to negatively affect ground water quality.

  15. The National Astronomy Consortium (NAC)

    Science.gov (United States)

    Von Schill, Lyndele; Ivory, Joyce

    2017-01-01

    The National Astronomy Consortium (NAC) program is designed to increase the number of underrepresented minority students into STEM and STEM careers by providing unique summer research experiences followed by long-term mentoring and cohort support. Hallmarks of the NAC program include: research or internship opportunities at one of the NAC partner sites, a framework to continue research over the academic year, peer and faculty mentoring, monthly virtual hangouts, and much more. NAC students also participate in two professional travel opportunities each year: the annual NAC conference at Howard University and poster presentation at the annual AAS winter meeting following their summer internship.The National Astronomy Consortium (NAC) is a program led by the National Radio Astronomy Consortium (NRAO) and Associated Universities, Inc. (AUI), in partnership with the National Society of Black Physicist (NSBP), along with a number of minority and majority universities.

  16. Astronomy education through interactive materials

    Science.gov (United States)

    Voelzke, Marcos Rincon; Antunes de Macêdo, Josué

    2015-08-01

    This study presents results of a survey conducted at the Federal Institution of Education, Science and Technology in the North of Minas Gerais (IFNMG), and aimed to investigate the potentialities of the use of interactive materials in the teaching of astronomy. An advanced training course with involved learning activities about basic concepts of astronomy was offered to thirty-two Licenciate students in Physics, Mathematics and Biological Sciences, using the mixed methodology, combined with the three pedagogical moments. Among other aspects, the viability of the use of resources was noticed, involving digital technologies and interactive materials on teaching of astronomy, which may contribute to the broadening of methodological options for future teachers and meet their training needs.

  17. International Olympiad on Astronomy and Astrophysics

    Science.gov (United States)

    Soonthornthum, B.; Kunjaya, C.

    2011-01-01

    The International Olympiad on Astronomy and Astrophysics, an annual astronomy and astrophysics competition for high school students, is described. Examples of problems and solutions from the competition are also given. (Contains 3 figures.)

  18. Nitrogen removal and nitrate leaching for forage systems receiving dairy effluent.

    Science.gov (United States)

    Woodard, Kenneth R; French, Edwin C; Sweat, Lewin A; Graetz, Donald A; Sollenberger, Lynn E; Macoon, Bisoondat; Portier, Kenneth M; Wade, Brett L; Rymph, Stuart J; Prine, Gordon M; Van Horn, Harold H

    2002-01-01

    Florida dairies need year-round forage systems that prevent loss of N to ground water from waste effluent sprayfields. Our purpose was to quantify forage N removal and monitor nitrate N (NO3(-)-N) concentrations in soil water below the rooting zone for two forage systems during four 12-mo cycles (1996-2000). Soil in the sprayfield is an excessively drained Kershaw sand (thermic, uncoated Typic Quartzipsamment). Over four cycles, average loading rates of effluent N were 500, 690, and 910 kg ha(-1) per cycle. Nitrogen removed by the bermudagrass (Cynodon spp.)-rye (Secale cereale L.) system (BR) during the first three cycles was 465 kg ha(-1) per cycle for the low loading rate, 528 kg ha(-1) for the medium rate, and 585 kg ha(-1) for the high. For the corn (Zea mays L.)-forage sorghum [Sorghum bicolor (L.) Moench]-rye system (CSR), N removals were 320 kg ha(-1) per cycle for the low rate, 327 kg ha(-1) for the medium, and 378 kg ha(-1) for the high. The higher N removals for BR were attributed to higher N concentration in bermudagrass (18.1-24.2 g kg(-1)) than in corn and forage sorghum (10.3-14.7 g kg(-1)). Dry matter yield declined in the fourth cycle for bermudagrass but N removal continued to be higher for BR than CSR. The BR system was much more effective at preventing NO3(-)-N leaching. For CSR, NO3(-)-N levels in soil water (1.5 m below surface) increased steeply during the period between the harvest of one forage and canopy dosure of the next. Overall, the BR system was better than CSR at removing N from the soil and maintaining low NO3(-)-N concentrations below the rooting zone.

  19. The Spectrum Landscape: Prospects for Terrestrial Radio Astronomy

    Science.gov (United States)

    Liszt, Harvey Steven

    2018-01-01

    Radio astronomers work within broad constraints imposed by commercial and other non-astronomical uses of the radio spectrum, somewhat modified to accommodate astronomy’s particular needs through the provision of radio quiet zones, radio frequency allocations, coordination agreements and other devices of spectrum management. As radio astronomers increase the instantaneous bandwidth, frequency coverage and sensitivity of their instruments, these external constraints, and not the limitations of their own instruments, will increasingly be the greatest obstacles to radio astronomy’s ability to observe the cosmos from the surface of the Earth. Therefore, prospects for future radio astronomy operations are contingent on situational awareness and planning for the impact of non-astronomical uses of the radio frequency spectrum. New radio astronomy instruments will have to incorporate adaptive reactions to external developments, and radio astronomers should be encouraged to think in untraditional ways. Increased attention to spectrum management is one of these. In this talk I’ll recap some recent developments such as the proliferation of 76 – 81 GHz car radar and orbiting earth-mapping radars, either of which can burn out a radio astronomy receiver. I’ll summarize present trends for non-astronomical radio spectrum use that will be coming to fruition in the next decade or so, categorized into terrestrial fixed and mobile, airborne and space-borne uses, sub-divided by waveband from the cm to the sub-mm. I’ll discuss how they will impact terrestrial radio astronomy and the various ways in which radio astronomy should be prepared to react. Protective developments must occur both within radio astronomy’s own domain – designing, siting and constructing its instruments and mitigating unavoidable RFI – and facing outward toward the community of other spectrum users. Engagement with spectrum management is no panacea but it is an important means, and perhaps the only

  20. Learning from the Starry Message: Using Galileo's "Sidereus Nuncius" in Introductory Astronomy Classes

    Science.gov (United States)

    Wiesner, Matthew P.

    2015-01-01

    Every introductory astronomy class encounters Galileo during the course as the first man to systematically study the sky with a telescope. Every Astronomy 101 student meets Galileo as one of the major catalysts behind the shift from the Ptolemaic to the Copernican system and as one of the great minds behind the scientific method. But most of the…

  1. Scalable Multifunction RF Systems: Combined vs. Separate Transmit and Receive Arrays

    NARCIS (Netherlands)

    Huizing, A.G.

    2008-01-01

    A scalable multifunction RF (SMRF) system allows the RF functionality (radar, electronic warfare and communications) to be easily extended and the RF performance to be scaled to the requirements of different missions and platforms. This paper presents the results of a trade-off study with respect to

  2. Nutrient cycling in an agroforestry alley cropping system receiving poultry litter or nitrogen fertilizer

    Science.gov (United States)

    Optimal utilization of animal manures as a plant nutrient source should also prevent adverse impacts on water quality. The objective of this study was to evaluate long-term poultry litter and N fertilizer application on nutrient cycling following establishment of an alley cropping system with easter...

  3. A new system for continuous and remote monitoring of patients receiving home mechanical ventilation.

    Science.gov (United States)

    Battista, L

    2016-09-01

    Home mechanical ventilation is the treatment of patients with respiratory failure or insufficiency by means of a mechanical ventilator at a patient's home. In order to allow remote patient monitoring, several tele-monitoring systems have been introduced in the last few years. However, most of them usually do not allow real-time services, as they have their own proprietary communication protocol implemented and some ventilation parameters are not always measured. Moreover, they monitor only some breaths during the whole day, despite the fact that a patient's respiratory state may change continuously during the day. In order to reduce the above drawbacks, this work reports the development of a novel remote monitoring system for long-term, home-based ventilation therapy; the proposed system allows for continuous monitoring of the main physical quantities involved during home-care ventilation (e.g., differential pressure, volume, and air flow rate) and is developed in order to allow observations of different remote therapy units located in different places of a city, region, or country. The developed remote patient monitoring system is able to detect various clinical events (e.g., events of tube disconnection and sleep apnea events) and has been successfully tested by means of experimental tests carried out with pulmonary ventilators typically used to support sick patients.

  4. Research of descriptions of collinear aerial receiving system ADS-B by numeral methods

    Directory of Open Access Journals (Sweden)

    В. П. Харченко

    2013-07-01

    Full Text Available Calculations of electric field intensity and directional diagrammes for colinear antennas using a method of moments in the framework of two program complexes are carried out. Comparison has shown high level of results coincidence. The sample of the antenna which is used in operating system for reception of ADS-B signals from airborne transponders is constructed

  5. New approach for receiving water objectives for overflows from sewer systems

    DEFF Research Database (Denmark)

    Larsen, Torben

    1999-01-01

    The paper describes the results of the work for the establishment of consistent objectives for storm overflows from sewer systems in respect to the physical conditions in streams and rivers in Denmark. First the result of a questionnaire is mentioned. Next some principles of the methods for formu...

  6. Project W-151 flexible receiver radiation detector system acceptance test plan. Revision 1

    International Nuclear Information System (INIS)

    Troyer, G.L.

    1994-01-01

    The attached document is the Acceptance Test Plan for the portion of Project W-151 dealing with acceptance of gamma-ray detectors and associated electronics manufactured at the Idaho National Engineering Laboratory (INEL). The document provides a written basis for testing the detector system, which will take place in the 305 building (300 Area)

  7. System analysis and energy model of 60GHz radio-triggered wireless sensor receiver

    NARCIS (Netherlands)

    Gao, H.; Wu, Y.; Matters - Kammerer, M.; Milosevic, D.; Linnartz, J.P.M.G.; Baltus, P.

    2013-01-01

    The optimization of a wireless system towards low power performance is not straightforward, it is the combination and trade-offs among different communication layers. In the physical layer, the frequency and the data rate are the fundamental parameters for optimizing power consumption in the

  8. Astronomy and Shakespeare's Hamlet.

    Science.gov (United States)

    Usher, P. D.

    1996-05-01

    Payne-Gaposchkin and others have suggested that Hamlet shows evidence of the Bard's awareness of the astronomical revolutions of the sixteenth century. I summarize major arguments and note that the play's themes recur in modern astronomy teaching and research: (1) The play amounts to a redefinition of universal order and humankind's position in it. (2) There is interplay between appearance and reality. Such a contrast is commonplace wherever superficial celestial appearances obscure underlying physical realities, the nature of which emerge as the tale unfolds. (3) The outermost sphere of the Ptolemaic and Copernican models seems to encase humanity, who are liberated by the reality of Digges' model and the implications advanced by Bruno. Similarly the oppressiveness of the castle interior is relieved by the observing platform which enables the heavens to be viewed in their true light. (4) Hamlet could be bounded in a nut-shell and count himself a king of infinite space, were it not that he has bad dreams. These concern the subversiveness of the new doctrine, for Hamlet refers to the infinite universe only hypothetically and in the presence of Rosencrantz and Guildenstern, who are named for relatives of the Danish astronomer Brahe. (5) Hamlet, and Brahe and Bruno, have connections to the university at Wittenberg, as does the Copernican champion Rheticus. (6) Ways are needed to reveal both the truths of nature, and the true nature of Danish royalty. Those unaccustomed to science think that there is madness in Hamlet's method. In particular, `doubt' is advanced as a methodological principle of inquiry. (7) The impression of normalcy and propriety in the upper reaches of society is like the false impression of an encapsulating universe. In Hamlet this duality is dramatized tragically, whereas in King John (cf. BAAS 27, 1325, 1995) it is not; for by 1601 when the writing of Hamlet was probably completed, Shakespeare would have known of the martyrdom of Bruno the previous

  9. Advances in astronomy and astrophysics

    CERN Document Server

    Kopal, Zdenek

    1963-01-01

    Advances in Astronomy and Astrophysics, Volume 2 brings together numerous research works on different aspects of astronomy and astrophysics. This volume is composed of six chapters and begins with a summary of observational record on twilight extensions of the Venus cusps. The next chapter deals with the common and related properties of binary stars, with emphasis on the evaluation of their cataclysmic variables. Cataclysmic variables refer to an object in one of three classes: dwarf nova, nova, or supernova. These topics are followed by discussions on the eclipse phenomena and the eclipses i

  10. Multiverso: Rock'n'Astronomy

    Science.gov (United States)

    Caballero, J. A.

    2012-05-01

    In the last few years, there have been several projects involving astronomy and classical music. But have a rock band ever appeared at a science conference or an astronomer at a rock concert? We present a project, Multiverso, in which we mix rock and astronomy, together with poetry and video art (Caballero, 2010). The project started in late 2009 and has already reached tens of thousands people in Spain through the release of an album, several concert-talks, television, radio, newspapers and the internet.

  11. Advances in astronomy and astrophysics

    CERN Document Server

    Kopal, Zdenek

    1966-01-01

    Advances in Astronomy and Astrophysics, Volume 4 brings together numerous research works on different aspects of astronomy and astrophysics. This volume is composed of five chapters, and starts with a description of objective prism and its application in space observations. The next chapter deals with the possibilities of deriving reliable models of the figure, density distribution, and gravity field of the Moon based on data obtained through Earth-bound telescopes. These topics are followed by a discussion on the ideal partially relativistic, partially degenerate gas in an exact manner. A ch

  12. Synthesis imaging in radio astronomy

    International Nuclear Information System (INIS)

    Perley, R.A.; Schwab, F.R.; Bridle, A.H.

    1989-01-01

    Recent advances in techniques and instrumentation for radio synthesis imaging in astronomy are discussed in a collection of review essays. Topics addressed include coherence in radio astronomy, the interferometer in practice, primary antenna elements, cross correlators, calibration and editing, sensitivity, deconvolution, self-calibration, error recognition, and image analysis. Consideration is given to wide-field imaging (bandwidth and time-average smearing, noncoplanar arrays, and mosaicking), high-dynamic-range imaging, spectral-line imaging, VLBI, solar imaging with a synthesis telescope, synthesis imaging of spatially coherent objects, noise in images of very bright sources, synthesis observing strategies, and the design of aperture-synthesis arrays

  13. Informal Education: Slacker Astronomy Podcasts

    Science.gov (United States)

    Price, A.

    2005-12-01

    Slacker Astronomy is a weekly podcast about astronomy begun in February, 2005. Each week we cover a recent astronomical news event. We present it with humor and silliness, yet we respect the intelligence of the audience and do not ``dumb it down." Since we are professional astronomers we often cover items ignored by traditional press. We currently have around 10,000 loyal weekly listeners. All our shows are rated for content and available to the public under the Creative Commons license. Both scripts and audio are also used as source material by parents, teachers and planetarium directors.

  14. Astronomy 3.0 Style

    Science.gov (United States)

    Accomazzi, A.

    2010-10-01

    Over the next decade, we will witness the development of a new infrastructure in support of data-intensive scientific research, which includes Astronomy. This new networked environment will offer both challenges and opportunities to our community and has the potential to transform the way data are described, curated and preserved. Based on the lessons learned during the development and management of the ADS, a case is made for adopting the emerging technologies and practices of the Semantic Web to support the way Astronomy research will be conducted. Examples of how small, incremental steps can, in the aggregate, make a significant difference in the provision and repurposing of astronomical data are provided.

  15. Indian Astronomy: The Missing Link in Eurocentric History of Astronomy

    Science.gov (United States)

    Haque, Shirin; Sharma, Deva

    2016-01-01

    A comprehensive history of Astronomy should show in reasonable chronological order, the contributions from wherever they arise in the world, once they are reliably documented. However, the authors note that consistently, the extremely rich contributions from Ancient Indian scholars like Aryabatha and Bhramagupta are omitted in Eurocentric…

  16. Blazing the Trail for Astronomy Education Research

    Science.gov (United States)

    Bailey, Janelle M.; Lombardi, Doug

    2015-01-01

    Education research has long considered student learning of topics in astronomy and the space sciences, but astronomy education research as a sub-field of discipline-based education research is relatively new. Driven by a growing interest among higher education astronomy educators in improving the general education, introductory science survey…

  17. The Explorer program for astronomy and astrophysics

    International Nuclear Information System (INIS)

    Savage, B.D.; Becklin, E.E.; Cassinelli, J.P.; Dupree, A.K.; Elliot, J.L.; Hoffmann, W.F.; Hudson, H.S.; Jura, M.; Kurfess, J.; Murray, S.S.

    1986-01-01

    This report was prepared to provide NASA with a strategy for proceeding with Explorer-class programs for research in space astronomy and astrophysics. The role of Explorers in astronomy and astrophysics and their past accomplishments are discussed, as are current and future astronomy and astrophysics Explorers. Specific cost needs for an effective Explorer program are considered

  18. Division B Commission 40: Radio Astronomy

    NARCIS (Netherlands)

    Chapman, Jessica M.; Giovaninni, Gabriele; Taylor, Russell; Carilli, Christopher; Hills, Richard; Hirabayashi, Hisashi; Jonas, Justin L.; Lazio, Joseph; Morganti, Raffaella; Nan, Rendong; Rubio, Monica; Shastri, Prjaval; Kellermann, Ken; Ekers, Ronald; Ohishi, Masatoshi

    2016-01-01

    IAU Commission 40 for Radio Astronomy (hereafter C40) brought together scientists and engineers who carry out observational and theoretical research in radio astronomy and who develop and operate the ground and space-based radio astronomy facilities and instrumentation. As of June 2015, the

  19. PMU Placement Methods in Power Systems based on Evolutionary Algorithms and GPS Receiver

    Directory of Open Access Journals (Sweden)

    M. R. Mosavi

    2013-06-01

    Full Text Available In this paper, optimal placement of Phasor Measurement Unit (PMU using Global Positioning System (GPS is discussed. Ant Colony Optimization (ACO, Simulated Annealing (SA, Particle Swarm Optimization (PSO and Genetic Algorithm (GA are used for this problem. Pheromone evaporation coefficient and the probability of moving from state x to state y by ant are introduced into the ACO. The modified algorithm overcomes the ACO in obtaining global optimal solution and convergence speed, when applied to optimizing the PMU placement problem. We also compare this simulink with SA, PSO and GA that to find capability of ACO in the search of optimal solution. The fitness function includes observability, redundancy and number of PMU. Logarithmic Least Square Method (LLSM is used to calculate the weights of fitness function. The suggested optimization method is applied in 30-bus IEEE system and the simulation results show modified ACO find results better than PSO and SA, but same result with GA.

  20. An EM System With Dramatic Multi-Axis Transmitter and Tensor Gradiometer Receiver

    Science.gov (United States)

    2011-06-01

    Thus, the main difference between the spatial behavior of target anomalies measured with a magnetometer and those we measured with an EM system is in...current efforts include the development of tensor magnetic gradiometers based on triaxial fluxgate technology by the USGS (Snyder & Bracken, Development...Superconducting gradiometer/ Magnetometer Arrays and a Novel Signal Processing Technique. IEEE Trans. on Magnetics, MAG-11(2), 701-707. EM Tensor Gradiometer

  1. An EM System with Dynamic Multi-Axis Transmitter and Tensor Gradiometer Receiver

    Science.gov (United States)

    2011-06-01

    main difference between the spatial behavior of target anomalies measured with a magnetometer and those we measured with an EM system is in the nature...environmental and UXO applications, current efforts include the development of tensor magnetic gradiometers based on triaxial fluxgate technology by the USGS...Superconducting gradiometer/ Magnetometer Arrays and a Novel Signal Processing Technique. IEEE Trans. on Magnetics, MAG-11(2), 701-707. EM Tensor

  2. Comparison of intelligence quotient in children surviving leukemia who received different prophylactic central nervous system treatments

    OpenAIRE

    Nahid, Reisi; Leila, Khalilian

    2012-01-01

    Background: Neurocognitive deficits and decrease in intelligence quotient (IQ) is one of the complication of prophylactic central nervous system (CNS) treatment in acute lymphoblastic leukemia (ALL) patients. In this study, we compare the IQ in survivors of ALL that were treated with different prophylactic CNS treatments. Materials and Methods : We compared 43 long-term survivors of ALL: 21 survivors with intrathecal methotrexate (IT MTX) as CNS prophylaxis, 22 with IT MTX+1800-2400 rads c...

  3. A Low-Power High-Dynamic-Range Receiver System for In-Probe 3-D Ultrasonic Imaging.

    Science.gov (United States)

    Attarzadeh, Hourieh; Xu, Ye; Ytterdal, Trond

    2017-10-01

    In this paper, a dual-mode low-power, high dynamic-range receiver circuit is designed for the interface with a capacitive micromachined ultrasonic transducer. The proposed ultrasound receiver chip enables the development of an in-probe digital beamforming imaging system. The flexibility of having two operation modes offers a high dynamic range with minimum power sacrifice. A prototype of the chip containing one receive channel, with one variable transimpedance amplifier (TIA) and one analog to digital converter (ADC) circuit is implemented. Combining variable gain TIA functionality with ADC gain settings achieves an enhanced overall high dynamic range, while low power dissipation is maintained. The chip is designed and fabricated in a 65 nm standard CMOS process technology. The test chip occupies an area of 76[Formula: see text] 170 [Formula: see text]. A total average power range of 60-240 [Formula: see text] for a sampling frequency of 30 MHz, and a center frequency of 5 MHz is measured. An instantaneous dynamic range of 50.5 dB with an overall dynamic range of 72 dB is obtained from the receiver circuit.

  4. Physics and astronomy of the Moon

    CERN Document Server

    Kopal, Zdenek

    2013-01-01

    Physics and Astronomy of the Moon focuses on the application of principles of physics in the study of the moon, including perturbations, equations, light scattering, and photometry. The selection first offers information on the motion of the moon in space and libration of the moon. Topics include Hill's equations of motion, non-solar perturbations, improved lunar ephemeris, optical and physical libration of the moon, and adjustment of heliometric observations of the moon's libration. The text then elaborates on the dynamics of the earth-moon system, photometry of the moon, and polarization of

  5. From "Frontiers of Astronomy" to Astrobiology

    Science.gov (United States)

    Kwok, Sun

    2011-10-01

    In his book Frontiers of Astronomy, Fred Hoyle outlined a number of ideas on the stellar synthesis of solid-state materials and their ejection into the interstellar medium. He also considered the possibility of interstellar organics being integrated into the early Earth during the accretion phase of planetary formation. These organics may have played a role in the origin of life and the creation of fossil fuels. In this paper, we assess these ideas with modern observational evidence, in particular on the evidence of stellar synthesis of complex organics and their delivery to the early Solar System.

  6. Music of the heavens Kepler's harmonic astronomy

    CERN Document Server

    Stephenson, Bruce

    2014-01-01

    Valued today for its development of the third law of planetary motion, Harmonice mundi (1619) was intended by Kepler to expand on ancient efforts to discern a Creator's plan for the planetary system--an arrangement thought to be based on harmonic relationships. Challenging critics who characterize Kepler's theories of harmonic astronomy as ""mystical,"" Bruce Stephenson offers the first thorough technical analysis of the music the astronomer thought the heavens made, and the logic that led him to find musical patterns in his data. In so doing, Stephenson illuminates crucial aspects of Kepler'

  7. Tumor blood flow and systemic shunting in patients receiving intraarterial chemotherapy for head and neck cancer

    International Nuclear Information System (INIS)

    Wheeler, R.H.; Ziessman, H.A.; Medvec, B.R.; Juni, J.E.; Thrall, J.H.; Keyes, J.W.; Pitt, S.R.; Baker, S.R.

    1986-01-01

    Radionuclide techniques have been used to estimate the systemic shunt and to quantitate blood flow to the tumor and a reference normal tissue in nine patients undergoing intraarterial chemotherapy for head and neck cancer. The systemic shunt was calculated as the percentage of pulmonary trapping of intraarterially injected /sup 99m/Tc-labeled macroaggregated albumin. The mean systemic shunt in the 12 separate arteries studied was 23 +/- 13% (SE) (range 8-43%). Quantitative blood flow was determined from the slope of the washout curve of intraarterially injected 133 Xe. The mean tumor blood flow was 13.6 +/- 6.7 ml/100 g/min, while the mean blood flow to the scalp was 4.2 +/- 2.1 ml/100 g/min providing a mean tumor/normal tissue ratio of 3.9 +/- 2.7. An estimate of blood flow distribution was obtained by calculating the ratio of counts/pixel in the tumor mass versus the remainder of the head as determined by single photon emission computed tomography following an intraarterial injection of /sup 99m/Tc-labeled macroaggregated albumin. The mean ratio of tumor to normal tissue perfusion by this technique was 5.6 +/- 3.7. These techniques have allowed noninvasive determination of the blood flow parameters associated with intraarterial chemotherapy. At least part of the therapeutic advantage of regional chemotherapy in patients with head and neck cancer is due to a tumor/normal tissue blood flow ratio that favors drug delivery to the tumor contained within the infused volume

  8. Optical timing receiver for the NASA Spaceborne Ranging System. Part I. Dual peak-sensing timing discriminator

    International Nuclear Information System (INIS)

    Leskovar, B.; Lo, C.C.; Zizka, G.

    1978-01-01

    Position-resolution capabilities of the NASA Spaceborne Laser Ranging System are essentially determined by the time-resolution capabilities of its optical timing receiver. The optical timing receiver consists of a fast photoelectric device; (e.g., photomultiplier or an avalanche photodiode detector), a timing discriminator, a high-precision event-timing digitizer, and a signal-processing system. The time-resolution capabilities of the receiver are determined by the photoelectron time spread of the photoelectric device, the time walk and resolution characteristics of the timing discriminator, and the resolution of the event-timing digitizer. It is thus necessary to evaluate available fast photoelectronic devices with respect to their time-resolution capabilities, to design a very low time walk timing discriminator and to develop a high-resolution event-timing digitizer which will be used in the high-resolution spaceborne laser ranging system receiver. The development of a new dual-peak sensing timing discriminator is described. The amplitude dependent time walk is less than +-150 psec for a 100:1 dynamic range of Gaussian-shaped input signals having pulse widths between 11 and 17 nsec. The unit produces 800 mV negative output pulses, each 10 nsec wide, and 3V positive pulses with widths of 15 nsec. The time delay through the discriminator is approximately 37 nsec. In this discriminator the input signal is processed by a peak-crossing circuit which produces a bipolar pulse having its zero-crossing point at the peak of the input signal. All essential functions in the discriminator are performed by means of tunnel diodes with backward diodes as nonlinear loads. The discriminator is designed to be CAMAC compatible to a conventional time-interval unit or a high-precision event timing digitizer. The adjustment procedure for obtaining minimum time walk is also given

  9. Discretionary decisions and disparities in receiving drug-eluting stents under a universal healthcare system: A population-based study.

    Directory of Open Access Journals (Sweden)

    Raymond N Kuo

    Full Text Available One of the main objectives behind the expansion of insurance coverage is to eliminate disparities in health and healthcare. However, researchers have not yet fully elucidated the reasons for disparities in the use of high-cost treatments among patients of different occupations. Furthermore, it remains unknown whether discretionary decisions made at the hospital level have an impact on the administration of high-cost interventions in a universal healthcare system. This study investigated the adoption of drug-eluting stents (DES versus bare metal-stents (BMS among patients in different occupations and income levels, with the aim of gauging the degree to which the inclination of health providers toward treatment options could affect treatment choices at the patient-level within a universal healthcare system.We adopted a cross-sectional observational study design using hierarchical modeling in conjunction with the population-based National Health Insurance database of Taiwan. Patients who received either a BMS or a DES between 2007 and 2010 were included in the study.During the period of study, 42,124 patients received a BMS (65.3% and 22,376 received DES (34.7%. Patients who were physicians or the family members of physicians were far more likely to receive DES (OR: 3.18, CI: 2.38-4.23 than were patients who were neither physicians nor in other high-status jobs (employers, other medical professions, or public service. Similarly, patients in the top 5% income bracket had a higher probability of receiving a DES (OR: 2.23, CI: 2.06-2.47, p 50% or between 25% and 50% was shown to be strongly associated with the selection of DESs (OR: 3.64 CI: 3.24-4.09 and OR: 2.16, CI: 2.01-2.33, respectively.Even under the universal healthcare system in Taiwan, socioeconomic disparities in the use of high-cost services remain widespread. Differences in the care received by patients of lower socioeconomic status may be due to the discretionary decisions of healthcare

  10. Frequent hemodialysis with NxStage system in pediatric patients receiving maintenance hemodialysis.

    Science.gov (United States)

    Goldstein, Stuart L; Silverstein, Douglas M; Leung, Jocelyn C; Feig, Daniel I; Soletsky, Beth; Knight, Cathy; Warady, Bradley A

    2008-01-01

    Recent evidence from adult hemodialysis (HD) patient studies reveal improved biochemical control and reported health-related quality of life after transition from conventional thrice weekly to daily home maintenance HD treatment. Published pediatric frequent dialysis experiences demonstrate similar improvement but all used conventional HD machines, which employ a treated municipal water supply, thereby frequently exposing patients to proinflammatory components. We report our pediatric experience with six-times-weekly HD using the NxStage system, which uses sterile dialysis fluid to provide dialysis in the home or center setting. Four patients (weight range 38-61.4 kg) completed the 16-week study. Patients exhibited progressive reductions in casual pretreatment systolic and diastolic blood pressures, discontinuation of antihypertensive medications, and decreased blood pressure load by ambulatory blood pressure monitoring. Mean serum phosphorus improved without change in phosphorus binder medication, and all three patients with a normalized protein catabolic rate 1.1 g/kg per day. Patients reported no adverse effects. Variable changes in proinflammatory cytokine levels were observed. We suggest that frequent HD with the NxStage system be considered for children who would benefit from home-based maintenance dialysis.

  11. A Novel WPT System Based on Dual Transmitters and Dual Receivers for High Power Applications: Analysis, Design and Implementation

    Directory of Open Access Journals (Sweden)

    Yong Li

    2017-02-01

    Full Text Available Traditional Wireless Power Transfer (WPT systems only have one energy transmission path, which can hardly meet the power demand for high power applications, e.g., railway applications (electric trains and trams, etc. due to the capacity constraints of power electronic devices. A novel WPT system based on dual transmitters and dual receivers is proposed in this paper to upgrade the power capacity of the WPT system. The reliability and availability of the proposed WPT system can be dramatically improved due to the four energy transmission paths. A three-dimensional finite element analysis (FEA tool ANSYS MAXWELL (ANSYS, Canonsburg, PA, USA is adopted to investigate the proposed magnetic coupling structure. Besides, the effects of the crossing coupling mutual inductances among the transmitters and receivers are analyzed. It shows that the same-side cross couplings will decrease the efficiency and transmitted power. Decoupling transformers are employed to mitigate the effects of the same-side cross couplings. Meanwhile, the output voltage in the secondary side can be regulated at its designed value with a fast response performance, and the system can continue work even with a faulty inverter. Finally, a scale-down experimental setup is provided to verify the proposed approach. The experimental results indicate that the proposed method could improve the transmitted power capacity, overall efficiency and reliability, simultaneously. The proposed WPT structure is a potential alternative for high power applications.

  12. Study of the Calibration Channel Width for a Digital Sideband Separating System for SIS 2SB Receiver

    Science.gov (United States)

    Khudchenko, Andrey; Finger, R.; Baryshev, A. M.; Mena, F. P.; Rodriguez, R.; Hesper, R.; Fuentes, R.; Bronfman, L.

    2018-01-01

    A Digital Sideband Separating (DSS) system has been recently applied to a full 2SB receiver, i.e., one with the analog IF hybrid still in place. This concept allows reaching IRR level around 45 dB and it presents additional advantages in calibration stability compared to the case when no IF hybrid is present. If implemented in multipixel cameras, the DSS system relaxes the requirements for the IRR level of the analog receiver substantially enabling to reach at least an IRR of 30 dB with relatively simple hardware. It would be ideal for spectral line surveys since it practically eliminates the line confusion in addition to rejecting the atmospheric noise in the image band. Therefore, the DSS system is a potential option for a future ALMA upgrade. Here we present our study on an important practical question: how wide should the calibration-channel width in order to reach a desired IRR level? This parameter determines, for a large part, the calibration speed of the DSS system and influences the back-end architecture. We estimate that for currently installed ALMA bands (B3-B8), the channel width of the DSS system can be at least 45 MHz to reach a 30db IRR level in entire band.

  13. Christoph Rothmann's compendium of astronomy of 1589. (German Title: Christoph Rothmanns Handbuch der Astronomie von 1589)

    Science.gov (United States)

    Granada, Miguel A.; Hamel, Jürgen; von Mackensen, Ludolf

    Around 1560, landgrave William IV. founded on his Cassel castle the first permanent observatory of modern times in Europe, and started to occupy himself with systematic sky observations. From the beginning, the main interest was focussed on the fixed stars, since William had recognized that exact position determinations were a prerequisite for further progress in astronomy. The observatory personnel was enlarged, in 1579, by the mathematician, clock-maker and instrument-maker Jost Bürgi, and in 1584 by the practical astronomer Christoph Rothmann. Since that time, intense work was carried out by creating a catalogue of fixed stars, based on own observations, which was completed in 1589. The accuracy of its stellar positions had not been reached in the past, and even superseded that of the almost contemporary catalogue by Tycho Brahe. Research in theoretical astronomy and cosmology at the landgrave's court in Cassel was also revolutionary: the acceptance of the heliocentric world system, investigations on refraction, the dismissal of the concept of solid planetary spheres and even that of a world ether, the nature of cometary tails, etc. Christoph Rothmann's work, edited here for the first time on the basis of the original manuscript, had been drafted as a commentary or introduction to his catalogue of fixed stars. He describes the construction and use of astronomical instruments, he unfolds his concepts of the system of the world on a heliocentric basis without solid planetary spheres to which he was lead by his research on refraction, he discusses the relation between astronomy and theology, and describes his revolutionary work on the Cassel star catalogue. This work constitutes a compendium of theoretical and practical astronomy of the late 16th century whose major scientific importance lies in the fact that it achieves scientific excellence in its time both because of the multitude of topics and because of the high level of discussion.

  14. Antibiotic resistance genes in municipal wastewater treatment systems and receiving waters in Arctic Canada

    DEFF Research Database (Denmark)

    Neudorf, Kara D.; Huang, Yan Nan; Ragush, Colin M.

    2017-01-01

    Domestic wastewater discharges may adversely impact arctic ecosystems and local indigenous people, who rely on being able to hunt and harvest food from their local environment. Therefore, there is a need to develop efficient wastewater treatment plants (WWTPs), which can be operated in remote...... communities under extreme climatic conditions. WWTPs have been identified as reservoirs of antibiotic resistance genes (ARGs). The objective of this work was to quantify the presence of nine different ARG markers (int1, sul1, sul2, tet(O), erm(B), mecA, blaCTX-M, blaTEM, and qnr(S)) in two passive systems...... (waste stabilization ponds [WSPs]) and one mechanical filtration plant operating in two smaller and one large community, respectively, in Nunavut, Canada. Measurement of water quality parameters (carbonaceous oxygen demand, ammonia, total suspended solids, Escherichia coli and total coliforms) showed...

  15. An artificial vision-based control system for automatic heliostat positioning offset correction in a central receiver solar power plant

    Energy Technology Data Exchange (ETDEWEB)

    Berenguel, M. [Universidad de Almeria, Dept. de Lenguajes y Computacion, La Canada Almeria (Spain); Rubio, F.R.; Lara, P.J.; Arahal, M.R.; Camacho, E.F.; Lopez, M. [Universidad de Sevilla, Dept. de Ingenieria de Sistemas y Automatica, Sevilla (Spain); Valverde, A. [Plataforma Solar de Almeria (PSA-CIEMAT), Tabernas (Almeria) (Spain)

    2004-07-01

    This paper presents the development of a simplified and automatic heliostat positioning offset correction control system using artificial vision techniques and common CCD devices. The heliostats of a solar power plant reflect solar radiation onto a receiver (in this case, a volumetric receiver) placed at the top of a tower in order to provide a desired energy flux distribution correlated with the coolant flow (in this case air mass flow) through the receiver, usually in an open loop control configuration. There exist error sources that increase the complexity of the control system, some of which are systematic ones, mainly due to tolerances, wrong mirror facets alignment (optical errors), errors due to the approximations made when calculating the solar position, etc., that produce errors (offsets) in the heliostat orientation (aiming point). The approximation adopted in this paper is based on the use of a B/W CCD camera to correct these deviations in an automatic way imitating the same procedure followed by the operators. The obtained images are used to estimate the distance between the sunbeam centroid projected by the heliostats and a target placed on the tower, this distance thus is used for low accuracy offset correction purposes. Basic threshold-based image processing techniques are used for automatic correction. (Author)

  16. Recent advances in infrared astronomy

    International Nuclear Information System (INIS)

    Robson, E.I.

    1980-01-01

    A background survey is given of developments in infrared astronomy during the last decade. Advantages obtained in using infrared wavelengths to penetrate the Earth's atmosphere and the detectors used for this work are considered. Infrared studies of, among other subjects, the stars, dust clouds, the centre of our galaxy and the 3k cosmic background radiation, are discussed. (UK)

  17. Utrecht and Galactic Radio Astronomy

    NARCIS (Netherlands)

    van Woerden, H.

    Important roles in early Dutch Galactic radio astronomy were played by several Utrecht astronomers: Van de Hulst, Minnaert and Houtgast. The poster announcing the conference contained a number of pictures referring to scientific achievements of the Astronomical Institute Utrecht. One of these

  18. Service Learning in Introductory Astronomy

    Science.gov (United States)

    Orleski, Michael

    2013-01-01

    Service learning is a method of instruction where the students in a course use the course's content in a service project. The service is included as a portion of the students' course grades. During the fall semester 2010, service learning was incorporated into the Introduction to Astronomy course at Misericordia University. The class had eight…

  19. Network for Astronomy School Education

    Science.gov (United States)

    Deustua, Susana E.; Ros, R. M.; Garcia, B.

    2014-01-01

    The Network for Astronomy School Education Project (NASE) was developed in response to the IAU's most recent 10 Years Strategic Plan to increase the efforts of the IAU in schools. NASE's mission is to stimulate teaching astronomy in schools, through professional development of primary and secondary school science teachers in developing and emerging countries. NASE's organizational principle is to build capacity by providing courses for three years in cooperation with a Local Organizing Committee (Local NASE Group). The Local NASE Group consists of 6-8 local university professors and education professional who will promote astronomy activities and organize future courses in subsequent years in their region of their country. NASE philosophy is to introduce low-tech astronomy, and has thus developed an a suite of activities that can be carried out with inexpensive, quotidian materials. Supporting these activities is a text for teachers, plus a complete set of instructional materials for each topic. These materials are available in English and Spanish, with future editions available in Chinese and Portuguese. We describe and discuss NASE activities in Central and South America from 2009 to the present.

  20. Thirty years of the new astronomy

    International Nuclear Information System (INIS)

    Rowan-Robinson, M.

    1990-01-01

    In an overview of advances in astrophysics over the last thirty years, the author expounds some of the important discoveries and how they have contributed to our understanding of star formation and evolution. The starting point for these new ideas has been exploring the non-visible radiations of the universe. Telescopes and observatories have been tuned to receive infrared, ultraviolet, x-ray, gamma ray and radiowave emissions. Radio astronomy revealed the existence of interstellar molecular clouds where stars are born. The discovery of the uniform microwave background radiation has suggested that the Universe started as a hot big bang. The inflationary model of cosmology provides answers to some problems of the big bang theory and predicts the existence of dark, nonluminous, matter which some infrared observations have confirmed. The author ends by providing a modern, astrophysical, description of the constellations so familiar to mediaeval astrologers. (UK)

  1. Design of high–order HTS dual–band bandpass filters with receiver subsystem for future mobile communication systems

    Energy Technology Data Exchange (ETDEWEB)

    Sekiya, N., E-mail: nsekiya@yamanashi.ac.jp

    2016-08-15

    Highlights: • We have developed two high-order HTS dual-band BPFs with a receiver subsystem for future mobile communication systems. • We developed a method for flexibly adjusting the coupling coefficient for the two passbands. • We demonstrated an HTS dual-band BPF receiver subsystem that uses a pulse tube cryocooler and a wideband LNA. • The proposed BPF is evaluated by simulation and measurement with good agreement. - Abstract: We have developed two high-order high-temperature superconducting (HTS) dual-band bandpass filters (BPFs) with a receiver subsystem for future mobile communication systems. They feature stub-loaded hair-pin resonators with two types of microstrip lines between them. One has a six-pole design, and the other has an eight-pole design. Both were designed to operate at 2.15 GHz with a 43-MHz (2%) bandwidth for the lower passband and at 3.50 GHz with a 70-MHz (2%) bandwidth for the upper one. They were fabricated using YBa{sub 2}Cu{sub 3}O{sub y} thin film on a CeO{sub 2}-bufferd r-Al{sub 2}O{sub 3} substrate. The measured results for both filters agree well with the simulated ones. The HTS dual-band BPF receiver subsystem uses a pulse tube cryocooler and a wideband low noise amplifier (LNA). We measured the frequency response of the six-pole dual-band BPF with and without a wideband LNA with a gain of 10 dB. The measured return losses were close.

  2. Interactions between physical, chemical and biological processes in aquatic systems - impacts on receiving waters with different contents of treated wastewater

    International Nuclear Information System (INIS)

    Kreuzinger, N.

    2000-08-01

    Two scenarios have be chosen within this PhD Thesis to describe the integrative key-significance of interactions between most relevant physical, chemical and biological processes in aquatic systems. These two case studies are used to illustrate and describe the importance of a detailed synthesis of biological, physical and chemical interactions in aquatic systems in order to provide relevant protection of water resources and to perform a sound water management. Methods are described to allow a detailed assessment of particular aspects within the complexity of the overall integration and therefore serve as a basis to determine the eventual necessity of proposed water management measures. Regarding the anthropogenic influence of treated wastewater on aquatic systems, one case study focuses on the interactions between emitted waters from a wastewater treatment plant and the resulting immission situation of its receiving water (The receiving water is quantitatively influenced by the treated wastewater by 95 %). This thesis proves that the effluent of wastewater treatment plants operated by best available technology meets the quality standards of running waters for the nutrients nitrogen and phosphorus, carbon-parameters, oxygen-regime and ecotoxicology. Within the second case study the focus is put on interactions between immissions and water usage. The general importance of biological phosphorus precipitation on the trophic situation of aquatic systems is described. Nevertheless, this generally known but within the field of applied limnology so far unrespected process of immobilization of phosphorus could be shown to represent a significant and major impact on phytoplannctotic development and eutrification. (author)

  3. Reconciling drainage and receiving basin signatures of the Godavari River system

    Science.gov (United States)

    Ojoshogu Usman, Muhammed; Kirkels, Frédérique Marie Sophie Anne; Zwart, Huub Michel; Basu, Sayak; Ponton, Camilo; Blattmann, Thomas Michael; Ploetze, Michael; Haghipour, Negar; McIntyre, Cameron; Peterse, Francien; Lupker, Maarten; Giosan, Liviu; Eglinton, Timothy Ian

    2018-06-01

    The modern-day Godavari River transports large amounts of sediment (170 Tg per year) and terrestrial organic carbon (OCterr; 1.5 Tg per year) from peninsular India to the Bay of Bengal. The flux and nature of OCterr is considered to have varied in response to past climate and human forcing. In order to delineate the provenance and nature of organic matter (OM) exported by the fluvial system and establish links to sedimentary records accumulating on its adjacent continental margin, the stable and radiogenic isotopic composition of bulk OC, abundance and distribution of long-chain fatty acids (LCFAs), sedimentological properties (e.g. grain size, mineral surface area, etc.) of fluvial (riverbed and riverbank) sediments and soils from the Godavari basin were analysed and these characteristics were compared to those of a sediment core retrieved from the continental slope depocenter. Results show that river sediments from the upper catchment exhibit higher total organic carbon (TOC) contents than those from the lower part of the basin. The general relationship between TOC and sedimentological parameters (i.e. mineral surface area and grain size) of the sediments suggests that sediment mineralogy, largely driven by provenance, plays an important role in the stabilization of OM during transport along the river axis, and in the preservation of OM exported by the Godavari to the Bay of Bengal. The stable carbon isotopic (δ13C) characteristics of river sediments and soils indicate that the upper mainstream and its tributaries drain catchments exhibiting more 13C enriched carbon than the lower stream, resulting from the regional vegetation gradient and/or net balance between the upper (C4-dominated plants) and lower (C3-dominated plants) catchments. The radiocarbon contents of organic carbon (Δ14COC) in deep soils and eroding riverbanks suggests these are likely sources of old or pre-aged carbon to the Godavari River that increasingly dominates the late Holocene portion of

  4. Research on teaching astronomy in the planetarium

    CERN Document Server

    Slater, Timothy F

    2017-01-01

    From a noted specialist in astronomy education and outreach, this Brief provides an overview of the most influential discipline-based science education research literature now guiding contemporary astronomy teaching. In recent years, systematic studies of effective and efficient teaching strategies have provided a solid foundation for enhancing college-level students’ learning in astronomy. Teaching astronomy and planetary science at the college-level was once best characterized as professor-centered, information-download lectures. Today, astronomy faculty are striving to drastically improve the learning environment by using innovative teaching approaches.  Uniquely, the authors have organized this book around strands of commonly employed astronomy teaching strategies to help readers, professors, and scholars quickly access the most relevant work while, simultaneously, avoiding the highly specialized, technical vocabulary of constructivist educational pedagogies unfamiliar to most astronomy professors. F...

  5. Modeling of coupling mechanism of wireless power transfer system and vibration phenomenon of receiver-coil in three-coil system

    Directory of Open Access Journals (Sweden)

    Suqi Liu

    2017-11-01

    Full Text Available Wireless power transfer (WPT via coupled magnetic resonances has become a focus recently, but the mechanisms responsible for such work are uncertain. We found that WPT system is a self-organization system by utilizing self-organization theory to judge. Firstly, the circuit model was established and transfer characteristic of a system was researched by utilizing circuit theories. Thus, with the introduction of entropy variable S, the energy equation of state can be established from the energy of the transmitter side and the energy of the receiver side. According to the energy equation of state, this paper obtains two equations when the reactance of the transmitter side and the receiver side equate to zero respectively. The vibration phenomenon of the receiver-coil in a three-coil WPT system was predicted and explained. Our findings illuminate the unusual self-organization in the WPT system and explain the vibration phenomenon of the receiver-coil in a three-coil WPT system.

  6. Modeling of coupling mechanism of wireless power transfer system and vibration phenomenon of receiver-coil in three-coil system

    Science.gov (United States)

    Liu, Suqi; Tan, Jianping; Wen, Xue

    2017-11-01

    Wireless power transfer (WPT) via coupled magnetic resonances has become a focus recently, but the mechanisms responsible for such work are uncertain. We found that WPT system is a self-organization system by utilizing self-organization theory to judge. Firstly, the circuit model was established and transfer characteristic of a system was researched by utilizing circuit theories. Thus, with the introduction of entropy variable S, the energy equation of state can be established from the energy of the transmitter side and the energy of the receiver side. According to the energy equation of state, this paper obtains two equations when the reactance of the transmitter side and the receiver side equate to zero respectively. The vibration phenomenon of the receiver-coil in a three-coil WPT system was predicted and explained. Our findings illuminate the unusual self-organization in the WPT system and explain the vibration phenomenon of the receiver-coil in a three-coil WPT system.

  7. Astronomy Student Activities Using Stellarium Software

    Science.gov (United States)

    Benge, Raymond D.; Tuttle, S. R.

    2012-01-01

    Planetarium programs can be used to provide a valuable learning experience for introductory astronomy students. Educational activities can be designed to utilize the capabilities of the software to display the sky, coordinates, motions in the sky, etc., in order to learn basic astronomical concepts. Most of the major textbook publishers have an option of bundling planetarium software and even laboratory activities using such software with textbooks. However, commercial planetarium software often is updated on a different schedule from the textbook revision and new edition schedule. The software updates also sometimes occur out of sync with college textbook adoption deadlines. Changes in software and activity curriculum often translate into increases costs for students and the college. To provide stability to the process, faculty at Tarrant County College have developed a set of laboratory exercises, entitled Distant Nature, using free open source Stellarium software. Stellarium is a simple, yet powerful, program that is available in formats that run on a variety of operating systems (Windows, Apple, linux). A web site was developed for the Distant Nature activities having a set version of Stellarium that students can download and install on their own computers. Also on the web site, students can access the instructions and worksheets associated with the various Stellarium based activities. A variety of activities are available to support two semesters of introductory astronomy. The Distant Nature web site has been used for one year with Tarrant County College astronomy students and is now available for use by other institutions. The Distant Nature web site is http://www.stuttle1.com/DN_Astro/index.html .

  8. DSP-Enabled Radio Astronomy: Towards IIIZW35 Reconquest

    Directory of Open Access Journals (Sweden)

    Alain Lecacheux

    2005-09-01

    Full Text Available In radio astronomy, the radio spectrum is used to detect weak emission from celestial sources. By spectral averaging, observation noise is reduced and weak sources can be detected. However, more and more observations are polluted by man-made radio frequency interferences (RFI. The impact of these RFIs on power spectral measurement ranges from total saturation to subtle distortions of the data. To some extent, elimination of artefacts can be achieved by blanking polluted channels in real time. With this aim in view, a complete real-time digital system has been implemented on a set of FPGA and DSP. The current functionalities of the digital system have high dynamic range of 70 dB, bandwidth selection facilities ranging from 875 kHz to 14 MHz, high spectral resolution through a polyphase filter bank with up to 8192 channels with 49 152 coefficients and real-time time-frequency blanking with a robust threshold detector. This receiver has been used to reobserve the IIIWZ35 astronomical source which has been scrambled by a strong satellite RFI for several years.

  9. Solar central receiver hybrid power system, Phase I. Volume 2. Conceptual design. Final technical report, October 1978-August 1979

    Energy Technology Data Exchange (ETDEWEB)

    None

    1979-09-01

    The objectives of this study were to develop a hybrid power system design that (1) produces minimum cost electric power, (2) minimizes the capital investment and operating cost, (3) permits capacity displacement, (4) and achieves utility acceptance for market penetration. We have met the first three of these objectives and therefore believe that the fourth, utility acceptance, will become a reality. These objectives have been met by utilizing the Martin Marietta concept that combines the alternate central receiver power system design and a high-temperature salt primary heat transfer fluid and thermal storage media system with a fossil-fired nonsolar energy source. Task 1 reviewed the requirements definition document and comments and recommendations were provided to DOE/San Francisco. Task 2 consisted of a market analysis to evaluate the potential market of solar hybrid power plants. Twenty-two utilities were selected within nine regions of the country. Both written and verbal correspondence was used to assess solar hybrid power plants with respect to the utilities' future requirements and plans. The parametric analysis of Task 3 evaluated a wide range of subsystem configurations and sizes. These analyses included subsystems from the solar standalone alternate central receiver power system using high-temperature molten salt and from fossil fuel nonsolar subsystems. Task 4, selection of the preferred commerical system configuration, utilized the parametric analyses developed in Task 3 to select system and subsystem configurations for the commercial plant design. Task 5 developed a conceptual design of the selected commercial plant configuration and assessed the related cost and performance. Task 6 assessed the economics and performance of the selected configuration as well as future potential improvements or limitations of the hybrid power plants.

  10. Purchased Behavioral Health Care Received by Military Health System Beneficiaries in Civilian Medical Facilities, 2000-2014.

    Science.gov (United States)

    Wooten, Nikki R; Brittingham, Jordan A; Pitner, Ronald O; Tavakoli, Abbas S; Jeffery, Diana D; Haddock, K Sue

    2018-02-06

    Behavioral health conditions are a significant concern for the U.S. military and the Military Health System (MHS) because of decreased military readiness and increased health care utilization. Although MHS beneficiaries receive direct care in military treatment facilities, a disproportionate majority of behavioral health treatment is purchased care received in civilian facilities. Yet, limited evidence exists about purchased behavioral health care received by MHS beneficiaries. This longitudinal study (1) estimated the prevalence of purchased behavioral health care and (2) identified patient and visit characteristics predicting receipt of purchased behavioral health care in acute care facilities from 2000 to 2014. Medical claims with Major Diagnostic Code 19 (mental disorders/diseases) or 20 (alcohol/drug disorders) as primary diagnoses and TRICARE as the primary/secondary payer were analyzed for MHS beneficiaries (n = 17,943) receiving behavioral health care in civilian acute care facilities from January 1, 2000, to December 31, 2014. The primary dependent variable, receipt of purchased behavioral health care, was modeled for select mental health and substance use disorders from 2000 to 2014 using generalized estimating equations. Patient characteristics included time, age, sex, and race/ethnicity. Visit types included inpatient hospitalization and emergency department (ED). Time was measured in days and visits were assumed to be correlated over time. Behavioral health care was described by both frequency of patients and visit type. The University of South Carolina Institutional Review Board approved this study. From 2000 to 2014, purchased care visits increased significantly for post-traumatic stress disorder, adjustment, anxiety, mood, bipolar, tobacco use, opioid/combination opioid dependence, nondependent cocaine abuse, psychosocial problems, and suicidal ideation among MHS beneficiaries. The majority of care was received for mental health disorders (78

  11. Journal of Astrophysics and Astronomy | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    2016-01-27

    Jan 27, 2016 ... Home; Journals; Journal of Astrophysics and Astronomy; Volume 30; Issue 3-4. Issue front cover thumbnail. Volume 30, Issue 3-4. September-December 2009, pages 133-210. pp 133-143. Close Separation Triple System QSO 1009-0252 with Discordant Redshifts: Is the Spectrum of One Component ...

  12. Student Understanding of Gravity in Introductory College Astronomy

    Science.gov (United States)

    Williamson, Kathryn E.; Willoughby, Shannon

    2012-01-01

    Twenty-four free-response questions were developed to explore introductory college astronomy students' understanding of gravity in a variety of contexts, including in and around Earth, throughout the solar system, and in hypothetical situations. Questions were separated into three questionnaires, each of which was given to a section of…

  13. Journal of Astrophysics and Astronomy | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    2016-01-27

    Jan 27, 2016 ... Home; Journals; Journal of Astrophysics and Astronomy; Volume 33; Issue 2. Issue front cover thumbnail. Volume 33, Issue 2. June 2012, pages 201-278. pp 201-211. Effect of Inhomogeneity of the Universe on a Gravitationally Bound Local System: A No-Go Result for Explaining the Secular Increase in the ...

  14. Autonomous Acoustic Receiver System

    Data.gov (United States)

    Federal Laboratory Consortium — FUNCTION: Collects underwater acoustic data and oceanographic data. Data are recorded onboard an ocean buoy and can be telemetered to a remote ship or shore station...

  15. On Fast Post-Processing of Global Positioning System Simulator Truth Data and Receiver Measurements and Solutions Data

    Science.gov (United States)

    Kizhner, Semion; Day, John H. (Technical Monitor)

    2000-01-01

    Post-Processing of data related to a Global Positioning System (GPS) simulation is an important activity in qualification of a GPS receiver for space flight. Because a GPS simulator is a critical resource it is desirable to move off the pertinent simulation data from the simulator as soon as a test is completed. The simulator data files are usually moved to a Personal Computer (PC), where the post-processing of the receiver logged measurements and solutions data and simulated data is performed. Typically post-processing is accomplished using PC-based commercial software languages and tools. Because of commercial software systems generality their general-purpose functions are notoriously slow and more than often are the bottleneck problem even for short duration experiments. For example, it may take 8 hours to post-process data from a 6-hour simulation. There is a need to do post-processing faster, especially in order to use the previous test results as feedback for a next simulation setup. This paper demonstrates that a fast software linear interpolation algorithm is applicable to a large class of engineering problems, like GPS simulation data post-processing, where computational time is a critical resource and is one of the most important considerations. An approach is developed that allows to speed-up post-processing by an order of magnitude. It is based on improving the post-processing bottleneck interpolation algorithm using apriori information that is specific to the GPS simulation application. The presented post-processing scheme was used in support of a few successful space flight missions carrying GPS receivers. A future approach to solving the post-processing performance problem using Field Programmable Gate Array (FPGA) technology is described.

  16. Receiver system for radio observation of high-energy cosmic ray air showers and its behaviour in self trigger mode

    International Nuclear Information System (INIS)

    Kroemer, Oliver

    2008-04-01

    The observation of high-energy cosmic rays is carried out by indirect measurements. Thereby the primary cosmic particle enters into the earth's atmosphere and generates a cosmic ray air shower by interactions with the air molecules. The secondary particles arriving at ground level are detected with particle detector arrays. The fluorescence light from the exited nitrogen molecules along the shower axis is observed with reflector telescopes in the near-ultraviolet range. In addition to these well-established detection methods, the radio observation of the geosynchrotron emission from cosmic ray air showers is investigated at present as a new observation method. Geosynchrotron emission is generated by the acceleration of the relativistic electron-positron-pairs contained in the air shower by Lorentz forces in the earth's magnetic field. At ground level this causes a single pulse of the electric field strength with a continuous frequency spectrum ranging from a few MHz to above 100 MHz. In this work, a suitable receiver concept is developed based on the signal properties of the geosynchrotron emission and the analysis of the superposed noise and radio frequency interferences. As the required receiver system was not commercially available, it was designed in the framework of this work and realised as system including the antenna, the receiver electronics and suitable data acquisition equipment. In this concept considerations for a large scale radio detector array have already been taken into account, like low power consumption to enable solar power supply and cost effectiveness. The result is a calibrated, multi-channel, digital wideband receiver for the complete range from 40 MHz to 80 MHz. Its inherent noise and RFI suppression essentially results from the antenna directional characteristic and frequency selectivity and allows effective radio observation of cosmic ray air showers also in populated environment. Several units of this receiver station have been deployed

  17. GLORI (GLObal navigation satellite system Reflectometry Instrument): A New Airborne GNSS-R receiver for land surface applications

    Science.gov (United States)

    Motte, Erwan; Zribi, Mehrez; Fanise, Pascal

    2015-04-01

    GLORI (GLObal navigation satellite system Reflectometry Instrument) is a new receiver dedicated to the airborne measurement of surface parameters such as soil moisture and biomass above ground and sea state (wave height and direction) above oceans. The instrument is based on the PARIS concept [Martin-Neira, 1993] using both the direct and surface-reflected L-band signals from the GPS constellation as a multistatic radar source. The receiver is based on one up-looking and one down-looking dual polarization hemispherical active antennas feeding a low-cost 4-channel SDR direct down-conversion receiver tuned to the GPS L1 frequency. The raw measurements are sampled at 16.368MHz and stored as 2-bit, IQ binary files. In post-processing, GPS acquisition and tracking are performed on the direct up-looking signal while the down-looking signal is processed blindly using tracking parameters from the direct signal. The obtained direct and reflected code-correlation waveforms are the basic observables for geophysical parameters inversion. The instrument was designed to be installed aboard the ATR42 experimental aircraft from the French SAFIRE fleet as a permanent payload. The long term goal of the project is to provide real-time continuous surface information for every flight performed. The aircraft records attitude information through its Inertial Measurement Unit and a commercial GPS receiver records additional information such as estimated doppler and code phase, receiver location, satellites azimuth and elevation. A series of test flights were performed over both the Toulouse and Gulf of Lion (Mediterranean Sea) regions during the period 17-21 Nov 2014 together with the KuROS radar [Hauser et al., 2014]. Using processing methods from the literature [Egido et al., 2014], preliminary results demonstrate the instrument sensitivity to both ground and ocean surface parameters estimation. A dedicated scientific flight campaign is planned at the end of second quarter 2015 with

  18. Fatal Candida septic shock during systemic chemotherapy in lung cancer patient receiving corticosteroid replacement therapy for hypopituitarism. A case report

    International Nuclear Information System (INIS)

    Morichika, Daisuke; Sato-Hisamoto, Akiko; Hotta, Katsuyuki

    2014-01-01

    Invasive candidiasis has increased as nosocomial infection recently in cancer patients who receive systemic chemotherapy, and the timely risk assessment for developing such specific infection is crucial. Especially in those concomitantly with hypopituitarism, febrile neutropenia with candidiasis can cause severe stress and lead potentially to sudden fatal outcome when the temporal steroid coverage for the adrenal insufficiency is not fully administered. We report a 72-year-old male case diagnosed as non-small-cell lung cancer, Stage 3A. He had received a steroid replacement therapy for the prior history of hypophysectomy due to pituitary adenoma with hydrocortisone of 3.3 mg/day, equivalent to prednisolone of 0.8 mg/day. This very small dosage of steroid was hardly supposed to weaken his immune system, but rather potentially led to an inappropriate supplementation of his adrenal function, assuming that the serum sodium and chlorine levels decreased. On Day 6 of second cycle of chemotherapy with carboplatin and paclitaxel, he developed sudden febrile neutropenia, septic shock and ileus, leading to death. After his death, the venous blood culture on Day 7 detected Candida albicans. Autopsy findings showed a massive necrotizing enterocolitis with extensive Candida invasion into submucous tissue. In conclusion, this case may suggest that (1) immediate initiation of antifungal therapy soon after the careful risk assessment of Candida infection and (2) adequate administration of both basal steroid replacement therapy and temporal steroid coverage for febrile neutropenia might have improved his fatal outcome. (author)

  19. An Analytical Approach for Performance Enhancement of FSO Communication System Using Array of Receivers in Adverse Weather Conditions

    Science.gov (United States)

    Nagpal, Shaina; Gupta, Amit

    2017-08-01

    Free Space Optics (FSO) link exploits the tremendous network capacity and is capable of offering wireless communications similar to communications through optical fibres. However, FSO link is extremely weather dependent and the major effect on FSO links is due to adverse weather conditions like fog and snow. In this paper, an FSO link is designed using an array of receivers. The disparity of the link for very high attenuation conditions due to fog and snow is analysed using aperture averaging technique. Further effect of aperture averaging technique is investigated by comparing the systems using aperture averaging technique with systems not using aperture averaging technique. The performance of proposed model of FSO link has been evaluated in terms of Q factor, bit error rate (BER) and eye diagram.

  20. Multimedia Astronomy Communication: Effectively Communicate Astronomy to the Desired Audience

    Science.gov (United States)

    Star Cartier, Kimberly Michelle; Wright, Jason

    2017-01-01

    A fundamental aspect of our jobs as scientists is communicating our work to others. In this, the field of astronomy holds the double-edged sword of ubiquitous fascination: the topic has been of interest to nearly the entire global population at some point in their lives, yet the learning curve is steep within any subfield and rife with difficult-to-synthesize details. Compounding this issue is the ever-expanding array of methods to reach people in today's Communications Era. Each communication medium has its own strengths and weaknesses, is appropriate in different situations, and requires its own specific skillset in order to maximize its functionality. Despite this, little attention is given to training astronomers in effective communication techniques, often relying on newcomers to simply pick up the ability by mimicking others and assuming that a firm grasp on the subject matter will make up for deficiencies in communication theory. This can restrict astronomers to a narrow set of communication methods, harming both the communicators and the audience who may struggle to access the information through those media.Whether writing a research paper to academic peers or giving an astronomy talk to a pubic audience, successfully communicating a scientific message requires more than just an expert grasp on the topic. A communicator must understand the makeup and prior knowledge of the desired audience, be able to break down the salient points of the topic into pieces that audience can digest, select and maximize upon a medium to deliver the message, and frame the message in a way that hooks the audience and compels further interest. In this work we synthesize the requirements of effective astronomy communication into a few key questions that every communicator needs to answer. We then discuss some of the most common media currently used to communicate astronomy, give both effective and poor examples of utilizing these media to communicate astronomy, and provide key

  1. Waste Receiving and Processing Facility PMS Test Report/DMS-Y2K/System Security DMS (Data Management System)

    International Nuclear Information System (INIS)

    PALMER, M.E.

    1999-01-01

    Test Plan HNF-4351 defines testing requirements for installation of a new server in the WRAP Facility. This documents shows the results of the test reports on the DMS-Y2K and DMS-F81 (Security) systems

  2. Imaging X-ray astronomy

    International Nuclear Information System (INIS)

    Elvis, M.

    1990-01-01

    The launch of the High Energy Astrophysical Observatory, more appealingly called the Einstein Observatory, marked one of the most revolutionary steps taken in astrophysics this century. Its greater sensitivity compared with earlier satellites and its ability to make high spacial and spectral resolution observations transformed X-ray astronomy. This book is based on a Symposium held in Cambridge, Massachusetts, to celebrate a decade of Einstein Observatory's achievements. It discusses the contributions that this satellite has made to each area of modern astrophysics and the diversity of the ongoing work based on Einstein data. There is a guide to each of the main data bases now coming on-line to increase the availability and to preserve this valuable archive for the future. A review of NASA's next big X-ray mission, AXAF, and a visionary program for novel X-ray astronomy satellites by Riccardo Giacconi conclude this wide-ranging volume. (author)

  3. Academic Training: Gravitational Waves Astronomy

    CERN Multimedia

    2006-01-01

    2006-2007 ACADEMIC TRAINING PROGRAMME LECTURE SERIES 16, 17, 18 October from 11:00 to 12:00 - Main Auditorium, bldg. 500 Gravitational Waves Astronomy M. LANDRY, LIGO Hanford Observatory, Richland, USA Gravitational wave astronomy is expected to become an observational field within the next decade. First direct detection of gravitational waves is possible with existing terrestrial-based detectors, and highly probable with proposed upgrades. In this three-part lecture series, we give an overview of the field, including material on gravitional wave sources, detection methods, some details of interferometric detectors, data analysis methods, and current results from observational data-taking runs of the LIGO and GEO projects. ENSEIGNEMENT ACADEMIQUE ACADEMIC TRAINING Françoise Benz 73127 academic.training@cern.ch If you wish to participate in one of the following courses, please tell to your supervisor and apply electronically from the course description pages that can be found on the Web at: http://www...

  4. Tangible Things of American Astronomy

    Science.gov (United States)

    Schechner, Sara Jane

    2018-01-01

    As a science that studies celestial objects situated at vast distances from us, astronomy deals with few things that can be touched directly. And yet, astronomy has many tangible things—scientific instruments, observatories, and log books, for example—which link the past to the present. There is little question about maintaining things still valuable for scientific research purposes, but why should we care about documenting and preserving the old and obsolete? One answer is that material things, when closely examined, enhance our knowledge of astronomy’s history in ways that written texts alone cannot do. A second answer is that learning about the past helps us live critically in the present. In brief case studies, this talk will find meaning in objects that are extraordinary or commonplace. These will include a sundial, an almanac, telescopes, clocks, a rotating desk, photographic plates, and fly spankers.

  5. LGBT Workplace Climate in Astronomy

    Science.gov (United States)

    Gaudi, B. S.; Danner, R.; Dixon, W. V.; Henderson, C. B.; Kay, L. E.

    2013-01-01

    The AAS Working Group on LGBTIQ Equality (WGLE) held a town hall meeting at the 220th AAS meeting in Anchorage to explore the workplace climate for LGBTIQ individuals working in Astronomy and related fields. Topics of discussion included anti-discrimination practices, general workplace climate, and pay and benefit policies. Four employment sectors were represented: industry, the federal government, private colleges, and public universities. We will summarize and expand on the town hall discussions and findings of the panel members.

  6. Dictionary of astronomy, space, and atmospheric phenomena

    International Nuclear Information System (INIS)

    Tver, D.F.; Motz, L.; Hartmann, W.K.

    1979-01-01

    This concise and up-to-date compendium features descriptions and definitions of terms, techniques and equipment relating to celestial phenomena. It explains the latest concepts in space exploration, planetary research, stellar astronomy, and meteorological science. The authors explore the general configurations of star groups, galaxy types, stars, and other small bodies in the solar system, including such important facts as magnitude of each and distance from Earth. They describe the brightest stars one by one. Vital data provided by the Viking, Mariner, and Pioneer space probes, the Voyager flights past Jupiter and its moons, and the Apollo landings are clearly presented and explained. New concepts in stellar astronomy such as quasars, neutron stars (pulsars), and black holes are precisely defined. Also included are discussions of meteor showers and the important rock types found on each planet; definitions of meteorological terms, ad astronomical equipment including telescopes, eyepieces and their accessories, the Golay cell, canopus sensor, filar micrometer, and more. Charts aid in identifying and locating stars and planets, and helpful reference tables list the location of the major celestial bodies - asteroids, constellations, the nearest stars, the brightest stars, interesting double and variable stars and cluters. Also included is the Meisser catalog of the coordinates and magnitudes for more than 100 celestial objects

  7. The X-ray Astronomy Recovery Mission

    Science.gov (United States)

    Tashiro, M.; Kelley, R.

    2017-10-01

    On 25 March 2016, the Japanese 6th X-ray astronomical satellite ASTRO-H (Hitomi), launched on February 17, lost communication after a series of mishap in its attitude control system. In response to the mishap the X-ray astronomy community and JAXA analyzed the direct and root cause of the mishap and investigated possibility of a recovery mission with the international collaborator NASA and ESA. Thanks to great effort of scientists, agencies, and governments, the X-ray Astronomy Recovery Mission (XARM) are proposed. The recovery mission is planned to resume high resolution X-ray spectroscopy with imaging realized by Hitomi under the international collaboration in the shortest time possible, simply by focusing one of the main science goals of Hitomi Resolving astrophysical problems by precise high-resolution X-ray spectroscopy'. XARM will carry a 6 x 6 pixelized X-ray micro-calorimeter on the focal plane of an X-ray mirror assembly, and an aligned X-ray CCD camera covering the same energy band and wider field of view, but no hard X-ray or soft gamma-ray instruments are onboard. In this paper, we introduce the science objectives, mission concept, and schedule of XARM.

  8. Astronomy in Brazilian music and poetry

    Science.gov (United States)

    de Freitas Mourão, Ronaldo Rogério

    2011-06-01

    The rôle of astronomy in the Brazilian cultural diversity -though little known world- has been enormous. Thus, the different forms of popular music and erudite, find musical compositions and lyrics inspired by the stars, the eclipses in rare phenomena such as the transit of Venus in front of the sun in 1882, the appearance of Halley's Comet in 1910, in the Big Bang theory. Even in the carnival parades of the blocks at the beginning of the century astronomy was present. More recently, the parade of 1997, the samba school Unidos do Viradouro, under the direction of Joãozinho Trinta, offered a new picture of the first moments of the creation of the universe to join in the white and dark in the components of their school, the idea of matter and anti-matter that reigned in the early moments of the creation of the universe in an explosion of joy. Examples in classical music include Dawn of Carlos Gomes and Carta Celeste by Almeida Prado. Unlike The Planets by Gustav Holst -who between 1914 and 1916 composed a symphonical tribute to the solar system based on astrology- Almeida Prado composed a symphony that is not limited to the world of planets, penetrating the deep cosmos of galaxies. Using various resources of the technique for the piano on the clusters and static movements, violent conflicts between the records of super acute and serious instrument, harpejos cross, etc . . .

  9. Astronomy Outreach for Large, Unique, and Unusual Audiences

    Science.gov (United States)

    Lubowich, Donald

    2015-08-01

    My successful outreach program venues include: outdoor concerts and festivals; the US National Mall; churches, synagogues, seminaries, or clergy conferences; the Ronald McDonald Houses of Long Island and Chicago; the Winthrop U. Hospital Children’s Medical Center the Fresh Air Fund summer camps (low-income and special needs); a Halloween star party (costumed kids look through telescopes); a Super Bowl Star Party (targeting women); Science Festivals (World, NYC; Princeton U.; the USA Science and Engineering Festival); and the NYC Columbus Day Parade. Information was also provided about local science museums, citizen science projects, astronomy educational sites, and astronomy clubs to encourage lifelong learning. In 2010 I created Astronomy Festival on the National Mall (co-sponsored by the White House Office of Science and Technology Policy) with the participation of astronomy clubs, scientific institutions and with Tyco Brahe, Johannes Kepler, and Caroline Herschel making guest appearances. My programs include solar, optical, and radio telescope observations, hands-on activities, a live image projection system; large outdoor posters and banners; videos; hands-on activities, and edible astronomy demonstrations.My NASA-funded Music and Astronomy Under the Stars (MAUS) program (60 events 2009 - 2013) reached 50,000 music lovers at local parks and the Central Park Jazz, Newport Folk, Ravinia, or Tanglewood Music Festivals with classical, folk, pop/rock, opera, Caribbean, or county-western concerts assisted by astronomy clubs. Yo-Yo-Ma, the Chicago and Boston Symphony Orchestras, Ravi Coltrane, Esperanza Spalding, Phish, Blood Sweat and Tears, Deep Purple, Tony Orlando, and Wilco performed at these events. MAUS reached underserved groups and attracted large crowds. Young kids participated in this family learning experience - often the first time they looked through a telescope. While < 50% of the participants took part in a science activity in the past year, they

  10. The 10 MWe Solar Thermal Central Receiver Pilot Plant: Solar facilities design integration. Pilot-plant station manual (RADL Item 2-1). Volume 1: System description

    Science.gov (United States)

    1982-09-01

    The complete Barstow Solar Pilot Plant is described. The plant requirements and general description are presented, the mechanical, electric power, and control and instrumentation systems as well as civil engineering and structural aspects and the station buildings are described. Included in the mechanical systems are the heliostats, receiver, thermal storage system, beam characterization system, steam, water, nitrogen, and compressed air systems, chemical feed system, fire protection system, drains, sumps and the waste disposal systems, and heating, ventilating, and air conditioning systems.

  11. Development of a high temperature solar receiver for high-efficient thermionic conversion systems; Fukugo netsuden henkan system yo chokoon taiyo junetsuki no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Umeoka, T; Naito, H; Yugami, H; Arashi, H [Tohoku University, Sendai (Japan). Faculty of Engineering

    1996-10-27

    For thermionic conversion systems (TIC) using concentrated sunlight as heat source, the newly developed solar receiver was tested. Concentrated sunlight aims at the inner surface of the cavity type solar receiver. The emitter of TIC installed in the rear of the solar receiver is uniformly heated over 1700K by thermal radiation from the rear of the solar receiver, emitting thermion. Electric power is generated by collecting the thermion by collector. Mo is used as emitter material, however, because of poor heat absorption of Mo, high-absorptive TiC is used for heat absorption surface to heat Mo by thermal conduction from high-temperature TiC. Functionally gradient material (FGM) with an intermediate layer of gradient TiC/Mo ratios between TiC and Mo is used as emitter material. The emitter is thus uniformly heated at high temperatures of 1723{plus_minus}12K. As a result, the developed solar receiver is applicable to heat the emitter of TIC. Heat flux measurement at the graphite cavity clarified that cavity temperature of as high as 1780K and heat flow of 50W/cm{sup 2} are obtained at 4.7kW in input. 6 figs.

  12. Cultural Astronomy in the Armenian Highland

    Science.gov (United States)

    Farmanyan, S. V.; Suvaryan, Yu. M.; Mickaelian, A. M. (Eds.)

    2016-12-01

    The book contains 29 articles of the Proceedings of the Young Scientists Conference "Cultural Astronomy in the Armenian Highland" held at the Armenian National Academy of Sciences on 20-23 June 2016. It consists of 4 main sections: "Introductory", "Cultural Astronomy", "Archaeoastronomy", "Scientific Tourism and Journalism, Astronomical Education and Amateur Astronomy". The book may be interesting to astronomers, culturologists, philologists, linguists, historians, archaeologists, art historians, ethnographers and to other specialists, as well as to students.

  13. Women in Early British and Irish Astronomy Stars and Satellites

    CERN Document Server

    Brück, Mary

    2009-01-01

    Careers in astronomy for women (as in other sciences) were a rarity in Britain and Ireland until well into the twentieth century. The book investigates the place of women in astronomy before that era, recounted in the form of biographies of about 25 women born between 1650 and 1900 who in varying capacities contributed to its progress during the eighteenth, nineteenth and early twentieth centuries. There are some famous names among them whose biographies have been written before now, there are others who have received less than their due recognition while many more occupied inconspicuous and sometimes thankless places as assistants to male family members. All deserve to be remembered as interesting individuals in an earlier opportunity-poor age. Placed in roughly chronological order, their lives constitute a sample thread in the story of female entry into the male world of science. The book is aimed at astronomers, amateur astronomers, historians of science, and promoters of women in science, but being writte...

  14. Cost Analysis of an Air Brayton Receiver for a Solar Thermal Electric Power System in Selected Annual Production Volumes

    Science.gov (United States)

    1981-01-01

    Pioneer Engineering and Manufacturing Company estimated the cost of manufacturing and Air Brayton Receiver for a Solar Thermal Electric Power System as designed by the AiResearch Division of the Garrett Corporation. Production costs were estimated at annual volumes of 100; 1,000; 5,000; 10,000; 50,000; 100,000 and 1,000,000 units. These costs included direct labor, direct material and manufacturing burden. A make or buy analysis was made of each part of each volume. At high volumes special fabrication concepts were used to reduce operation cycle times. All costs were estimated at an assumed 100% plant capacity. Economic feasibility determined the level of production at which special concepts were to be introduced. Estimated costs were based on the economics of the last half of 1980. Tooling and capital equipment costs were estimated for ach volume. Infrastructure and personnel requirements were also estimated.

  15. Improving Astronomy Achievement and Attitude through Astronomy Summer Project: A Design, Implementation and Assessment

    Science.gov (United States)

    Türk, Cumhur; Kalkan, Hüseyin; Iskeleli', Nazan Ocak; Kiroglu, Kasim

    2016-01-01

    The purpose of this study is to examine the effects of an astronomy summer project implemented in different learning activities on elementary school students, pre-service elementary teachers and in-service teachers' astronomy achievement and their attitudes to astronomy field. This study is the result of a five-day, three-stage, science school,…

  16. The Relationship between Preservice Science Teachers' Attitude toward Astronomy and Their Understanding of Basic Astronomy Concepts

    Science.gov (United States)

    Bektasli, Behzat

    2016-01-01

    Turkish preservice science teachers have been taking a two-credit astronomy class during the last semester of their undergraduate program since 2010. The current study aims to investigate the relationship between preservice science teachers' astronomy misconceptions and their attitudes toward astronomy. Preservice science teachers were given an…

  17. Systemic and localized infection by Candida species in patients with rheumatic diseases receiving anti-TNF therapy

    Directory of Open Access Journals (Sweden)

    Nadia E. Aikawa

    Full Text Available ABSTRACT Objective: To evaluate the prevalence of systemic and localized infection by Candida species and its possible association with demographic, clinical and laboratory manifestations and therapy in patients with rheumatic diseases taking TNF blockers. Methods: Consecutive patients with rheumatic diseases receiving anti-TNF agents were included. The following risk factors up to four weeks prior to the study were analyzed: use of antibiotics, immunosuppressant drugs, hospitalization and invasive procedures. All subjects were evaluated for clinical complaints; specific blood cultures were obtained for fungi and blood samples were collected for Candida spp. detection by polymerase chain reaction. Results: 194 patients [67 with rheumatoid arthritis (RA, 47 with ankylosing spondylitis (AS, 36 with juvenile idiopathic arthritis (JIA, 28 with psoriatic arthritis and 16 with other conditions] were included. The average age of patients was 42 ± 16 years, with 68 (35% male and mean disease duration of 15 ± 10 years. Sixty-four (33% patients were receiving adalimumab, 59 (30% etanercept and 71 (36% infliximab. Eighty-one percent of patients were concomitantly taking immunosuppressant drugs. At the time of the study, only one (0.5% patient had localized fungal infection (vaginal candidiasis. None of the patients included had systemic candidiasis with positive blood cultures for fungi or PCR positive for Candida spp. in peripheral blood sample. Conclusions: This was the first study to assess the prevalence of invasive and localized fungal disease by Candida in a significant number of patients with rheumatic diseases on anti-TNF therapy, and demonstrated low risk of candidiasis, despite the high prevalence of immunosuppressive drug use.

  18. Response of Global Navigation Satellite System receivers to known shaking between 0.2 and 20 Hertz

    Science.gov (United States)

    Langbein, John; Evans, John R.; Blume, Fredrick; Johanson, Ingrid

    2014-01-01

    Over the past decade, several technological advances have allowed Global Navigation Satellite Systems (GNSS) receivers to have the capability to record displacements at high frequencies, with sampling rates approaching 100 samples per second (sps). In addition, communication and computer hardware and software have allowed various institutions, including the U.S. Geological Survey (USGS), to retrieve, process, and display position changes recorded by a network of GNSS sites with small, less than 1-s delays between the time that the GNSS receiver records signals from a constellation of satellites and the time that the position is estimated (a method known as “real-time”). These improvements in hardware and software have allowed the USGS to process GNSS (or a subset of the GNSS, the Global Positioning System, GPS) data in real-time at 1 sps with the goal of determining displacements from earthquakes and volcanoes in real-time. However, the current set of GNSS equipment can record at rates of 100 sps, which allows the possibility of using this equipment to record earthquake displacements over the full range of frequencies that typically are recorded by acceleration and velocity transducers. The advantage of using GNSS to record earthquakes is that the displacement, rather than acceleration or velocity, is recorded, and for large earthquakes, the GNSS sensor stays on scale and will not distort the observations due to clipping of the signal at its highest amplitude. The direct observation of displacement is advantageous in estimating the size and spatial extent of the earthquake rupture. Otherwise, when using velocity or acceleration sensors, the displacements are determined by numerical integration of the observations, which can introduce significant uncertainty in the estimated displacements. However, GNSS technology can, at best, resolve displacements of a few millimeters, and for most earthquakes, their displacements are less than 1 mm. Consequently, to be useful

  19. Current Status of the IAU Working Group for Numerical Standards of Fundamental Astronomy

    National Research Council Canada - National Science Library

    Luzum, B; Capitaine, N; Fienga, A; Folkner, W; Fukushima, T; Hilton, J; Hohenkerk, C; Krasinsky, G; Petit, G; Pitjeva, E; Soffel, M; Wallace, P

    2007-01-01

    ...) for Numerical Standards of Fundamental Astronomy. The goal of the WG are to update "IAU Current Best Estimates" conforming with IAU Resolutions, the International Earth Rotation and Reference System Service (IERS...

  20. Low-level software for the pentek 6510 digital receiver board applied to the new AD beam measurement system

    CERN Document Server

    Angoletta, Maria Elena

    2002-01-01

    The new beam measurement system for the CERN Antiproton Decelerator heavily relies on a Pentek 6510 Digital Receiver (DRX) board. The new system goal is to extract beam parameters from pickup signals. Its digital implementation allows for higher precision, easier management of the hardware as well as modification and improvement with no hardware change. In this scheme, this innovative VME DRX board is responsible for parallel data acquisition, independent digital down conversion and processing of up to 4 digitised inputs. The in-house- developed low-level code (LLC), running on the board, takes care of several tasks, such as interfacing with the Real Time Task (RTT), data processing and board managing. The RTT runs on a PowerPC VME board and controls the DRX board as a master. The LLC is a state machine developed in C and Assembler, which services several interrupts and performs the FFT of complex input data. The DRX low-level system developed is highly modular and easily adaptable to other processing scenari...