WorldWideScience

Sample records for citizen band radio

  1. 47 CFR 95.401 - (CB Rule 1) What are the Citizens Band Radio Services?

    Science.gov (United States)

    2010-10-01

    ... for personal or business activities of the general public. The CB Radio Service may also be used for... service providing auditory assistance to persons with disabilities, persons who require language... functions involving implanted and body-worn medical devices. The rules for this service are contained...

  2. Local radio, public opinion and citizen participation

    OpenAIRE

    BUENDÍA ASTUDILLO, ALEXANDER; Doctor Educación Univ. Del Cauca; Pino Correa, Juan Carlos; Universidad del Cauca, Popayán - Cauca

    2008-01-01

    This paper shows how local radio stations that foster citizen participation and public opinion can develop into agents of social mobilization, as long they hold a broad notion of democracy. The article gives an account of the involvement that the ECCO research group (Universidad del Cauca, Colombia) has had in the project “Citizen radio: Room for democracy”, where researchers have given support to local radio stations and have sought to understand how these media conceive, assume and work tow...

  3. The Radio Meteor Zoo: a citizen science project

    Science.gov (United States)

    Calders, S.; Verbeeck, C.; Lamy, H.; Martínez Picar, A.

    2016-01-01

    Scientists from the BRAMS radio meteor network have started a citizen science project called Radio Meteor Zoo in collaboration with Zooniverse in order to identify meteor reflections in BRAMS spectrograms. First, a small-scale version of the Radio Meteor Zoo was carried out with a sample of meteor identifications in 12 spectrograms by 35 volunteers. Results are presented here and allowed us to define a method that reliably detects meteor reflections based on the identifications by the volunteers. It turns out that, if each spectrogram is inspected by 10 volunteers, hit and false detection percentages of 95% respectively 6% are expected. The Radio Meteor Zoo is online at https://www.zooniverse.org/projects/zooniverse/radio-meteor-zoo. Citizen scientists are kindly invited to inspect spectrograms.

  4. Radio Band Observations of Blazar Variability

    CERN Document Server

    Aller, Margo F; Hughes, Philip A

    2010-01-01

    The properties of blazar variability in the radio band are studied using the unique combination of temporal resolution from single dish monitoring and spatial resolution from VLBA imaging; such measurements, now available in all four Stokes parameters, together with theoretical simulations, identify the origin of radio band variability and probe the characteristics of the radio jet where the broadband blazar emission originates. Outbursts in total flux density and linear polarization in the optical-to-radio bands are attributed to shocks propagating within the jet spine, in part based on limited modeling invoking transverse shocks; new radiative transfer simulations allowing for shocks at arbitrary angle to the flow direction confirm this picture by reproducing the observed centimeter-band variations observed more generally, and are of current interest since these shocks may play a role in the gamma-ray flaring detected by Fermi. Recent UMRAO multifrequency Stokes V studies of bright blazars identify the spec...

  5. Link adaptation in unlicensed radio bands

    NARCIS (Netherlands)

    Haartsen, Jaap C.; Schutter, George B.W.

    2005-01-01

    This paper presents a new collaborative mechanism for efficient coordination of radio communication devices, in particular addressing the unlicensed ISM band at 2.4 GHz. As the traffic in the ISM band is increasing tremendously, the potential for interference between uncoordinated devices is becomin

  6. Radio Band Observations of Blazar Variability

    Indian Academy of Sciences (India)

    Margo F. Aller; Hugh D. Aller; Philip A. Hughes

    2011-03-01

    The properties of blazar variability in the radio band are studied using the unique combination of temporal resolution from single dish monitoring and spatial resolution from VLBA imaging. Such measurements now available in all four Stokes parameters, together with theoretical simulations, identify the origin of radio band variability and probe the characteristics of the radio jet where the broadband blazar emission originates. Outbursts in total flux density and linear polarization in the optical-to-radio bands are attributed to shocks propagating within the jet spine, in part, based on limited modelling invoking transverse shocks; new radiative transfer simulations allowing for shocks at arbitrary angle to the flow direction confirm this picture by reproducing the observed centimeter-band variations observed more generally, and are of current interest since these shocks may play a role in the -ray flaring detected by Fermi. Recent UMRAO multifrequency Stokes V studies of bright blazars identify the spectral variability properties of circular polarization for the first time and demonstrate that polarity flips are relatively common. All-Stokes data are consistent with the production of circular polarization by linear-to-circular mode conversion in a region that is at least partially selfabsorbed. Detailed analysis of single-epoch, multifrequency, all-Stokes VLBA observations of 3C 279 support this physical picture and are best explained by emission from an electron-proton plasma.

  7. The Red Radio Ring: a gravitationally lensed hyperluminous infrared radio galaxy at z=2.553 discovered through citizen science

    CERN Document Server

    Geach, J E; Verma, A; Marshall, P J; Jackson, N; Belles, P -E; Beswick, R; Baeten, E; Chavez, M; Cornen, C; Cox, B E; Erben, T; Erickson, N J; Garrington, S; Harrison, P A; Harrington, K; Hughes, D H; Ivison, R J; Jordan, C; Lin, Y -T; Leauthaud, A; Lintott, C; Lynn, S; Kapadia, A; Kneib, J -P; Macmillan, C; Makler, M; Miller, G; Montana, A; Mujica, R; Muxlow, T; Narayanan, G; Briain, D O; O'Brien, T; Oguri, M; Paget, E; Parrish, M; Ross, N P; Rozo, E; Rusu, E; Rykoff, E S; Sanchez-Arguelles, D; Simpson, R; Snyder, C; Schloerb, F P; Tecza, M; Van Waerbeke, L; Wilcox, J; Viero, M; Wilson, G W; Yun, M S; Zeballos, M

    2015-01-01

    We report the discovery of a gravitationally lensed hyperluminous infrared galaxy (L_IR~10^13 L_sun) with strong radio emission (L_1.4GHz~10^25 W/Hz) at z=2.553. The source was identified in the citizen science project SpaceWarps through the visual inspection of tens of thousands of iJKs colour composite images of Luminous Red Galaxies (LRGs), groups and clusters of galaxies and quasars. Appearing as a partial Einstein ring (r_e~3") around an LRG at z=0.2, the galaxy is extremely bright in the sub-millimetre for a cosmological source, with the thermal dust emission approaching 1 Jy at peak. The redshift of the lensed galaxy is determined through the detection of the CO(3-2) molecular emission line with the Large Millimetre Telescope's Redshift Search Receiver and through [OIII] and H-alpha line detections in the near-infrared from Subaru/IRCS. We have resolved the radio emission with high resolution (300-400 mas) eMERLIN L-band and JVLA C-band imaging. These observations are used in combination with the near-...

  8. Experimental radio frequency link for Ka-band communications applications

    Science.gov (United States)

    Fujikawa, Gene; Conray, Martin J.; Saunders, Alan L.; Pope, Dale E.

    1988-01-01

    An experimental radio frequency link has been demonstrated to provide two-way communication between a remote user ground terminal and a ground-based Ka-band transponder. Bit-error-rate performance and radio frequency characteristics of the communication link were investigated.

  9. The Red Radio Ring: a gravitationally lensed hyperluminous infrared radio galaxy at z = 2.553 discovered through the citizen science project SPACE WARPS

    Science.gov (United States)

    Geach, J. E.; More, A.; Verma, A.; Marshall, P. J.; Jackson, N.; Belles, P.-E.; Beswick, R.; Baeten, E.; Chavez, M.; Cornen, C.; Cox, B. E.; Erben, T.; Erickson, N. J.; Garrington, S.; Harrison, P. A.; Harrington, K.; Hughes, D. H.; Ivison, R. J.; Jordan, C.; Lin, Y.-T.; Leauthaud, A.; Lintott, C.; Lynn, S.; Kapadia, A.; Kneib, J.-P.; Macmillan, C.; Makler, M.; Miller, G.; Montaña, A.; Mujica, R.; Muxlow, T.; Narayanan, G.; O'Briain, D.; O'Brien, T.; Oguri, M.; Paget, E.; Parrish, M.; Ross, N. P.; Rozo, E.; Rusu, Cristian E.; Rykoff, E. S.; Sanchez-Argüelles, D.; Simpson, R.; Snyder, C.; Schloerb, F. P.; Tecza, M.; Wang, W.-H.; Van Waerbeke, L.; Wilcox, J.; Viero, M.; Wilson, G. W.; Yun, M. S.; Zeballos, M.

    2015-09-01

    We report the discovery of a gravitationally lensed hyperluminous infrared galaxy (intrinsic LIR ≈ 1013 L⊙) with strong radio emission (intrinsic L1.4 GHz ≈ 1025 W Hz-1) at z = 2.553. The source was identified in the citizen science project SPACE WARPS through the visual inspection of tens of thousands of iJKs colour composite images of luminous red galaxies (LRGs), groups and clusters of galaxies and quasars. Appearing as a partial Einstein ring (re ≈ 3 arcsec) around an LRG at z = 0.2, the galaxy is extremely bright in the sub-millimetre for a cosmological source, with the thermal dust emission approaching 1 Jy at peak. The redshift of the lensed galaxy is determined through the detection of the CO(3→2) molecular emission line with the Large Millimetre Telescope's Redshift Search Receiver and through [O III] and Hα line detections in the near-infrared from Subaru/Infrared Camera and Spectrograph. We have resolved the radio emission with high-resolution (300-400 mas) eMERLIN L-band and Very Large Array C-band imaging. These observations are used in combination with the near-infrared imaging to construct a lens model, which indicates a lensing magnification of μ ≈ 10. The source reconstruction appears to support a radio morphology comprised of a compact (<250 pc) core and more extended component, perhaps indicative of an active nucleus and jet or lobe.

  10. Tracking Galaxy Evolution Through Low-Frequency Radio Continuum Observations using SKA and Citizen-Science Research using Multi-Wavelength Data

    Science.gov (United States)

    Hota, Ananda; Konar, C.; Stalin, C. S.; Vaddi, Sravani; Mohanty, Pradeepta K.; Dabhade, Pratik; Dharmik Bhoga, Sai Arun; Rajoria, Megha; Sethi, Sagar

    2016-12-01

    We present a brief review of progress in the understanding of general spiral and elliptical galaxies, through merger, star formation and AGN activities. With reference to case studies performed with the GMRT, we highlight the unique aspects of studying galaxies in the radio wavelengths where powerful quasars and bright radio galaxies are traditionally the dominating subjects. Though AGN or quasar activity is extremely energetic, it is extremely short-lived. This justify focussing on transitional galaxies to find relic-evidences of the immediate past AGN-feedback which decide the future course of evolution of a galaxy. Relic radio lobes can be best detected in low frequency observations with the GMRT, LOFAR and in future SKA. The age of these relic radio plasma can be as old as a few hundred Myr. There is a huge gap between this and what is found in optical bands. The very first relic-evidences of a past quasar activity (Hanny's Voorwerp) was discovered in 2007 by a Galaxy Zoo citizen-scientist, a school teacher, in the optical bands. This relic is around a few tens of thousand years old. More discoveries needed to match these time-scales with star formation time-scales in AGN host galaxies to better understand black hole galaxy co-evolution process via feedback-driven quenching of star formation. It is now well-accepted that discovery and characterization of such faint fuzzy relic features can be more efficiently done by human eye than a machine. Radio interferometry images are more complicated than optical and need the citizen-scientists to be trained. RAD@home, the only Indian citizen-science research project in astronomy, analysing TIFR GMRT Sky Survey (TGSS) 150 MHz data and observing from the Giant Meterwave Radio Telescope (GMRT), was launched in April 2013. Unique, zero-infrastructure zero-funded design of RAD@home as a collaboratory of 69 trained e-astronomers is briefly described. Some of the new-found objects like episodic radio galaxies, radio-jet and

  11. Tracking Galaxy Evolution Through Low-Frequency Radio Continuum Observations using SKA and Citizen-Science Research using Multi-Wavelength Data

    Indian Academy of Sciences (India)

    Ananda Hota; C. Konar; C. S. Stalin; Sravani Vaddi; Pradeepta K. Mohanty; Pratik Dabhade; Sai Arun Dharmik Bhoga; Megha Rajoria; Sagar Sethi

    2016-12-01

    We present a brief review of progress in the understanding of general spiral and elliptical galaxies, through merger, star formation and AGN activities. With reference to case studies performed with the GMRT, we highlight the unique aspects of studying galaxies in the radio wavelengths where powerful quasars and bright radio galaxies are traditionally the dominating subjects. Though AGN or quasar activity is extremely energetic, it is extremely short-lived. This justify focussing on transitional galaxies to find relic-evidences of the immediate past AGN-feedback which decide the future course of evolution of a galaxy. Relic radio lobes can be best detected in low frequency observations with the GMRT, LOFAR and in future SKA. The age of these relic radio plasma can be as old as a few hundred Myr. There is a huge gap between this and what is found in optical bands. The very first relic-evidences of a past quasar activity (Hanny’s Voorwerp) was discovered in 2007 by a Galaxy Zoo citizen-scientist, a school teacher, in the optical bands. This relic is around a few tens of thousand years old. More discoveries needed to match these time-scales with star formation time-scales in AGN host galaxies to better understand black hole galaxy co-evolution process via feedback-driven quenching of star formation. It is now well-accepted that discovery and characterization of such faint fuzzy relic features can be more efficiently done by human eye than a machine. Radio interferometry images are more complicated than optical and need the citizen-scientists to be trained. RAD@home, the only Indian citizen-science research project in astronomy, analysing TIFR GMRT Sky Survey (TGSS) 150 MHz data and observing from the Giant Meterwave Radio Telescope (GMRT), was launched in April 2013. Unique, zero-infrastructure zero-funded design of RAD@home as a collaboratory of 69 trained e-astronomers is briefly described. Some of the new-found objects like episodic radio galaxies, radio-jet and

  12. Citizens’ Radio in North Africa and the Middle East: Meaningful Change through Citizen Empowerment? – An Experience from Tunis

    Directory of Open Access Journals (Sweden)

    Stefanie Groth

    2013-12-01

    Full Text Available Fostering a participatory political culture is a crucial part of the on-going transformation processes which we witness across North African and Middle Eastern countries since 2011. This paper considers which role participatory communication plays in these processes, by examining the potential of citizens’ radios to accompany Tunisia’s transition at a grassroots level. Analysing the case of Radio 6 Tunis – a local, non-commercial Internet-radio founded by Tunisian journalists under the rule of Ben Ali in 2007 – citizens’ radios are discussed as sites of political contestation and cultivation of critical consciousness. While they empower citizens to reclaim both their voice and public space, their influence is however limited. The manifold challenges which citizens' radios face in the transitional context of post-autocratic Tunisia, may well impede nascent democratisation dynamics.

  13. Citizen Science Air Sensor Project with Clean Air Carolina and the Eastern Band of Cherokee Indians Fact Sheet

    Science.gov (United States)

    EPA scientists are partnering with Clean Air Carolina (CAC) in Charlotte, N.C., and the Eastern Band of Cherokee Indians (EBCI) in Cherokee, N.C., to conduct a citizen science air quality project in these regions.

  14. RFID Transponders' Radio Frequency Emissions in Aircraft Communication and Navigation Radio Bands

    Science.gov (United States)

    Nguyen, Truong X.; Ely, Jay J.; Williams, Reuben A.; Koppen, Sandra V.; Salud, Maria Theresa P.

    2006-01-01

    Radiated emissions in aircraft communication and navigation bands are measured from several active radio frequency identification (RFID) tags. The individual tags are different in design and operations. They may also operate in different frequency bands. The process for measuring the emissions is discussed, and includes tag interrogation, reverberation chamber testing, and instrument settings selection. The measurement results are described and compared against aircraft emission limits. In addition, interference path loss for the cargo bays of passenger aircraft is measured. Cargo bay path loss is more appropriate for RFID tags than passenger cabin path loss. The path loss data are reported for several aircraft radio systems on a Boeing 747 and an Airbus A320.

  15. A Quasi-Periodic Solar Radio Fluctuation at Microwave Band

    Institute of Scientific and Technical Information of China (English)

    XU Fu-Ying; HUANG Guang-Li; WU Hong-Ao

    2005-01-01

    @@ A rare but interesting solar radio fine structure, quasi-periodic fluctuations, on 25 August 1999 was observed at microwave band for the first time. They fluctuated initially at a nearly stable frequency level then at a reverse drift component up to 5.49 GHz. The individual fluctuation consists of a bi-directional drift component. The features are characterized by narrow bandwidth of △ f / f ≤ 3%, quasi-periodicity of~ 100 ms as well as a slowly reverse and a rapidly normal drift rates on the bi-directional drift component. The associated data of the Yohkoh soft and hard x-ray telescope and Nobeyama radio heliograph at 17 GHz showed that there are several bright spots (i.e. inhomogeneities) along the soft x-ray loop, and the locations of both radio and soft x-ray sources are closely consistent. Therefore, the fluctuations are most likely caused by the inhomogeneities within a flare loop.Based on the two-component atmospheric model, we suggest a three-component atmospheric model with large sc ale length λ and small scale lengths λ1 and λ2 to describe equilibrium atmosphere and inhomogeneity. With the beam model, the characters of fluctuations may be interpreted reasonably by the quasi-equidistant inhomogeneity along a flare loop.

  16. Ka-Band Transponder for Deep-Space Radio Science

    Science.gov (United States)

    Dennis, Matthew S.; Mysoor, Narayan R.; Folkner, William M.; Mendoza, Ricardo; Venkatesan, Jaikrishna

    2008-01-01

    A one-page document describes a Ka-band transponder being developed for use in deep-space radio science. The transponder receives in the Deep Space Network (DSN) uplink frequency band of 34.2 to 34.7 GHz, transmits in the 31.8- to 32.3 GHz DSN downlink band, and performs regenerative ranging on a DSN standard 4-MHz ranging tone subcarrier phase-modulated onto the uplink carrier signal. A primary consideration in this development is reduction in size, relative to other such transponders. The transponder design is all-analog, chosen to minimize not only the size but also the number of parts and the design time and, thus, the cost. The receiver features two stages of frequency down-conversion. The receiver locks onto the uplink carrier signal. The exciter signal for the transmitter is derived from the same source as that used to generate the first-stage local-oscillator signal. The ranging-tone subcarrier is down-converted along with the carrier to the second intermediate frequency, where the 4-MHz tone is demodulated from the composite signal and fed into a ranging-tone-tracking loop, which regenerates the tone. The regenerated tone is linearly phase-modulated onto the downlink carrier.

  17. New radio observations of the Moon at L band

    Institute of Scientific and Technical Information of China (English)

    Xi-Zhen Zhang; Andrew Gray; Yan Su; Jun-Duo Li; Tom Landecker; Hong-Bo Zhang; Chun-Lai Li

    2012-01-01

    We present results of new radio observations of the Moon at L band with the synthesis telescope of the Dominion Radio Astrophysical Observatory Synthesis Telescope.The resolution and temperature sensitivity of the observations are 159″ ×87″ and 1.7 K,respectively.The main results are:(1) the lunar brightness temperature averaged over the whole disk is about 233 K while the average brightness temperature for the four quadrants are 228.1 K (NE),239.7 K (NW),233.9 K (SW) and 228.8 K (SE).The observations reveal large temperature and spatial variations on the Moon for the first time.The highest brightness temperature is about 257 K and it is located along the lunar equator,to the west.The total uncertainty is about 5% due to the absolute accuracy of the fluxes of the primary calibrators; (2) the total degree of polarization is about 6%.Both polarization intensity and degree of polarization increase from the disk's center to the limb,and the distribution of the degree of polarization along the limb is not uniform; (3) the new data are used to study the properties of regolith,such as dielectric constant and thickness distribution.The results show that the lunar regolith's thickness increases from the NW (mare area) to the SE (highland area) regions on the lunar surface.

  18. Radio frequency electromagnetic field compliance assessment of multi-band and MIMO equipped radio base stations.

    Science.gov (United States)

    Thors, Björn; Thielens, Arno; Fridén, Jonas; Colombi, Davide; Törnevik, Christer; Vermeeren, Günter; Martens, Luc; Joseph, Wout

    2014-05-01

    In this paper, different methods for practical numerical radio frequency exposure compliance assessments of radio base station products were investigated. Both multi-band base station antennas and antennas designed for multiple input multiple output (MIMO) transmission schemes were considered. For the multi-band case, various standardized assessment methods were evaluated in terms of resulting compliance distance with respect to the reference levels and basic restrictions of the International Commission on Non-Ionizing Radiation Protection. Both single frequency and multiple frequency (cumulative) compliance distances were determined using numerical simulations for a mobile communication base station antenna transmitting in four frequency bands between 800 and 2600 MHz. The assessments were conducted in terms of root-mean-squared electromagnetic fields, whole-body averaged specific absorption rate (SAR) and peak 10 g averaged SAR. In general, assessments based on peak field strengths were found to be less computationally intensive, but lead to larger compliance distances than spatial averaging of electromagnetic fields used in combination with localized SAR assessments. For adult exposure, the results indicated that even shorter compliance distances were obtained by using assessments based on localized and whole-body SAR. Numerical simulations, using base station products employing MIMO transmission schemes, were performed as well and were in agreement with reference measurements. The applicability of various field combination methods for correlated exposure was investigated, and best estimate methods were proposed. Our results showed that field combining methods generally considered as conservative could be used to efficiently assess compliance boundary dimensions of single- and dual-polarized multicolumn base station antennas with only minor increases in compliance distances.

  19. Correlation between -Ray and Radio Bands for -Ray Loud Blazars

    Indian Academy of Sciences (India)

    D. X. Wu; J. H. Fan; S. H. Li

    2014-09-01

    The most identified sources observed by Fermi are blazars (Flat Spectrum Radio Quasars (FSRQs) and BL Lacertae objects (BLs). In this paper, we obtained 124 -ray loud blazars with available -ray and radio (core and total) data. It is interesting that the -ray luminosity have a good correlation with the radio luminosity. This phenomenon exists in the core radio luminosity (c) and total radio luminosity (t). The correlation between the -ray and the radio luminosities is still stronger even after we eliminated the redshift effect, which suggests that the -ray radiations in the -ray loud blazars are strongly beamed.

  20. L-band orthomode transducer for the Sardinia Radio Telescope

    Science.gov (United States)

    Navarrini, Alessandro; Pisanu, Tonino

    2008-07-01

    We describe the design, construction, and characterization results of a compact L-band (1.3-1.8 GHz) Orthomode Transducer (OMT) for the Sardinia Radio Telescope (SRT), a 64 m diameter telescope which is being built in the Sardinia island, Italy. The OMT consists of three distinct mechanical parts connected through ultra low loss coaxial cables: a turnstile junction and two identical 180° hybrid power combiners. The turnstile junction is based on a circular waveguide input (diameter of 190 mm,) and on four WR650 rectangular waveguide cavities from which the RF signals are extracted using coaxial probes. The OMT was optimized using a commercial 3D electromagnetic simulator. The main mechanical part of the turnstile junction was machined out of an Aluminum block whose final external shape is a cylinder with diameter 450 mm and height 98 mm. From 1.3 to 1.8 GHz the measured reflection coefficient was less than -22 dB, the isolation between the outputs was less than -45 dB, and the cross polarization was less than -50 dB for both polarization channels.

  1. Diagnostics of the ionospheric turbulence by wide band radio signals

    Science.gov (United States)

    Sergeev, Evgeny; Shindin, Alexey; Grach, Savely

    Results of the investigations of the time-space structure of the HF-pumped ionospheric volume above the SURA heating facility are presented. The method of investigations is based on mea-surements of the amplitude and phase of pulsed (pulse duration diagnostics, technical capabilities of SURA transmitter-receiver system, specially elaborated time-frequency modes of transmitter operation, space diversity three point reception, wide band signal recording, digital filtering, spectral and correlation analysis of the short radio pulses reflected from ionosphere were used. As a result of numerically solved in-verse problem of vertical sounding of the HF-perturbed ionosphere, dynamic behavior of the electron plasma density variations was obtained in the regions close to plasma resonance and upper hybrid resonance of the pump wave. In our experiments the pumping usually leaded to plasma expulsion from the resonance regions. A magnitude of artificial plasma density pertur-bations achieved 0.8% from the background density for pump power about P 60 MW ERP. The methods of a similarity and full correlation analysis were used for pulse signal amplitude processing, which were obtained by diversity three point reception with the receiving aerial separation of 84 m. As a result, novel data on fine structure of the space field of the vertical and horizontal velocities of plasma in the perturbed ionosphere volume with high time (up to 20 ms) and frequency (˜ 1 kHz) resolution are obtained. This frequency resolution can be translated into altitude resolution (˜ 50-100 m) in the ionosphere. The work was supported by RFBR grants 10-02-00642, 09-02-01150 and Federal Special-purpose Program "Scientific and pedagogical personnel of innovative Russia".

  2. Discovery of Correlated Behavior Between the HXR and the Radio Bands in Cygnus X-3

    CERN Document Server

    McCollough, M L; Zhang, S N; Harmon, B A; Hjellming, R M; Waltman, E B; Foster, R S; Ghigo, F D; Briggs, M S; Pendleton, G N; Johnston, K J

    1999-01-01

    Using CGRO/BATSE hard X-ray (HXR) data and GHz radio monitoring data from the Green Bank Interferometer (GBI), we have performed a long term study ($\\sim$ 1800 days) of the unusual X-ray binary Cyg X-3 resulting in the discovery of a remarkable relationship between these two wavelength bands. We find that, during quiescent radio states, the radio flux is strongly anticorrelated with the intensity of the HXR emission. The relationship switches to a correlation with the onset of major radio flaring activity. During major radio flaring activity the HXR drops to a very low intensity during quenching in the radio and recovers during the radio flare. Injection of plasma into the radio jets of Cyg X-3 occurs during changes in the HXR emission and suggests that disk-related and jet-related components are responsible for the high energy emission.

  3. Non-thermal emission from extragalactic radio sources a high resolution broad band (radio to X-rays) approach

    CERN Document Server

    Brunetti, G

    2002-01-01

    In the framework of the study of extragalactic radio sources, we will focus on the importance of the spatial resolution at different wavelengths, and of the combination of observations at different frequency bands. In particular, a substantial step forward in this field is now provided by the new generation X-ray telescopes which are able to image radio sources in between 0.1--10 keV with a spatial resolution comparable with that of the radio telescopes (VLA) and of the optical telescopes. After a brief description of some basic aspects of acceleration mechanisms and of the radiative processes at work in the extragalactic radio sources, we will focus on a number of recent radio, optical and X-ray observations with arcsec resolution, and discuss the deriving constraints on the physics of these sources.

  4. High Performance Ka Band Power Amplifiers for Future EVA Radio Applications Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In this proposal, AlphaSense, Inc. and the University of Washington detail the development of a novel, high performance Ka band power amplifier for EVA radio...

  5. Design and Validation of High Date Rate Ka-Band Software Defined Radio for Small Satellite

    Science.gov (United States)

    Xia, Tian

    2016-01-01

    The Design and Validation of High Date Rate Ka- Band Software Defined Radio for Small Satellite project will develop a novel Ka-band software defined radio (SDR) that is capable of establishing high data rate inter-satellite links with a throughput of 500 megabits per second (Mb/s) and providing millimeter ranging precision. The system will be designed to operate with high performance and reliability that is robust against various interference effects and network anomalies. The Ka-band radio resulting from this work will improve upon state of the art Ka-band radios in terms of dimensional size, mass and power dissipation, which limit their use in small satellites.

  6. 225m Outdoor W-Band Radio-over-Fiber Link Using an Optical SFP+ Module

    DEFF Research Database (Denmark)

    Rommel, Simon; Rodríguez Páez, Juan Sebastián; Chorchos, Łukasz

    2016-01-01

    A W-band radio-over-fiber link based on a commercial SFP+ module is demonstrated, allowing easy integration into existing PON solutions. Without active laser control good RF frequency stability and 225m wireless distance are achieved......A W-band radio-over-fiber link based on a commercial SFP+ module is demonstrated, allowing easy integration into existing PON solutions. Without active laser control good RF frequency stability and 225m wireless distance are achieved...

  7. Potential radio frequency interference with the GPS L5 band for radio occultation measurements

    Directory of Open Access Journals (Sweden)

    A. M. Wolff

    2014-05-01

    Full Text Available New Radio Occultation (RO receivers are planned to utilize the newly implemented Global Positioning System (GPS L5 signal centered at 1176.45 MHz. Since there are currently no operational GPS L5 receivers used for space-based RO applications, the interference environment is unclear. Distance Measuring Equipment (DME and Tactical Air Navigation (TACAN stations share the same frequency band as the GPS L5 signal. DME/TACAN signals have been identified to be a means of interference for any GPS L5 receiver. This study focuses on implementing a Systems Tools Kit (STK simulation to gain insight into the power received by a RO satellite in Low Earth Orbit (LEO from a DME/TACAN transmission. In order to confirm the validity of utilizing STK for communication purposes, a theoretical scenario was recreated as a simulation and the results were confirmed. Once the method was validated, STK was used to output a received power level aboard a RO satellite from a DME/TACAN station as well as a tool to predict the number of interfering DME/TACAN stations at any point in time. Taking a conservative approach, the signal power received was much greater than the typical power level received by a RO satellite from a GPS satellite transmission. This relatively high received power along with a high number of interfering DME/TACAN stations as an RO satellite passes over North America or Western Europe indicate that DME/TACAN interference may conflict with RO receivers.

  8. Shared broadcast channel for radio systems in the 2.4 GHz band

    NARCIS (Netherlands)

    Bekkaoui, Abdel; Haartsen, Jaap C.

    2005-01-01

    This paper presents a new collaborative mechanism for efficient coordination of radio communication devices, in particular addressing the unlicensed ISM band at 2.4 GHz. As the traffic in the ISM band is increasing tremendously, the potential for interference between uncoordinated devices is becomin

  9. Digitally-Enhanced Software-Defined Radio Receiver Robust to Out-of-Band Interference

    NARCIS (Netherlands)

    Ru, Zhiyu; Moseley, Niels A.; Klumperink, Eric A.M.; Nauta, Bram

    2009-01-01

    A software-defined radio (SDR) receiver with improved robustness to out-of-band interference (OBI) is presented. Two main challenges are identified for an OBI-robust SDR receiver: out-of-band nonlinearity and harmonic mixing. Voltage gain at RF is avoided, and instead realized at baseband in combina

  10. 15Gbit/s Duobinary Transmission Over a W-Band Radio-over-Fiber Link

    DEFF Research Database (Denmark)

    Rommel, Simon; Vegas Olmos, Juan José; Tafur Monroy, Idelfonso

    2016-01-01

    In this paper the transmission of a 15Gbit/s duobinary signal over a W-band hybrid photonic wireless link is demonstrated experimentally. The radio-over-fiber link consists of 10km SMF and a wireless distance of 50m, utilizing RF carriers at 83–87GHz. Transmission of a 15Gbit/s duobinary signal...

  11. A GPU-Based Wide-Band Radio Spectrometer

    CERN Document Server

    Chennamangalam, Jayanth; Jones, Glenn; Chen, Hong; Ford, John; Kepley, Amanda; Lorimer, D R; Nie, Jun; Prestage, Richard; Roshi, D Anish; Wagner, Mark; Werthimer, Dan

    2014-01-01

    The Graphics Processing Unit (GPU) has become an integral part of astronomical instrumentation, enabling high-performance online data reduction and accelerated online signal processing. In this paper, we describe a wide-band reconfigurable spectrometer built using an off-the-shelf GPU card. This spectrometer, when configured as a polyphase filter bank (PFB), supports a dual-polarization bandwidth of up to 1.1 GHz (or a single-polarization bandwidth of up to 2.2 GHz) on the latest generation of GPUs. On the other hand, when configured as a direct FFT, the spectrometer supports a dual-polarization bandwidth of up to 1.4 GHz (or a single-polarization bandwidth of up to 2.8 GHz).

  12. Mars Reconnaissance Orbiter: Ka Band Radio Science Experiments and the Effect of the Troposphere

    Science.gov (United States)

    Asmar, Sami W.; Morabito, David

    2006-01-01

    This viewgraph presentation reviews the possibilities of utilizing the telecommunication links between spacecraft and Earth to examine changes in the phase/frequency, amplitude, and polarization of radio signals to investigate, specifically for the Mars Reconnaissance Orbiter (MRO)mission utilizes X-band coherent (uplink and downlink) carrier Doppler and range for its gravity investigation Gravity team will also take advantage of Ka-band downlink signal Tropospheric calibration data from Advanced Water Vapor Radiometer (AWVR) will be used. The calibration of the received Ka band signal for the effect of the troposphere is discussed.

  13. Integrated Common Radio Resource Management with Spectrum Aggregation over Non-Contiguous Frequency Bands

    DEFF Research Database (Denmark)

    Cabral, Orlando; Meucci, Filippo; Mihovska, Albena D.;

    2011-01-01

    This paper proposes an integrated Common Radio Resource Management (iCRRM). The iCRRM performs classic CRRM functionalities jointly with Spectrum Aggregation (SA), being able to switch users between non-contiguous frequency bands. The SA scheduling is obtained with an optimised General Multi......-Band Scheduling (GMBS) algorithm with the aim of cell throughput maximisation. In particular, we investigate the dependence of the throughput on the cell coverage distance for the allocation of users over the 2 and 5 GHz bands for a single operator scenario under a constant average Signal to Interference...

  14. Constraining the Solar Coronal Magnetic Field Strength using Split-band Type II Radio Burst Observations

    Science.gov (United States)

    Kishore, P.; Ramesh, R.; Hariharan, K.; Kathiravan, C.; Gopalswamy, N.

    2016-11-01

    We report on low-frequency radio (85-35 MHz) spectral observations of four different type II radio bursts, which exhibited fundamental-harmonic emission and split-band structure. Each of the bursts was found to be closely associated with a whitelight coronal mass ejection (CME) close to the Sun. We estimated the coronal magnetic field strength from the split-band characteristics of the bursts, by assuming a model for the coronal electron density distribution. The choice of the model was constrained, based on the following criteria: (1) when the radio burst is observed simultaneously in the upper and lower bands of the fundamental component, the location of the plasma level corresponding to the frequency of the burst in the lower band should be consistent with the deprojected location of the leading edge (LE) of the associated CME; (2) the drift speed of the type II bursts derived from such a model should agree closely with the deprojected speed of the LE of the corresponding CMEs. With the above conditions, we find that: (1) the estimated field strengths are unique to each type II burst, and (2) the radial variation of the field strength in the different events indicate a pattern. It is steepest for the case where the heliocentric distance range over which the associated burst is observed is closest to the Sun, and vice versa.

  15. RFID Transponders' RF Emissions in Aircraft Communication and Navigation Radio Bands

    Science.gov (United States)

    Nguyen, Truong X.; Ely, Jay J.; Koppen Sandra V.; Fersch, Mariatheresa S.

    2008-01-01

    Radiated emission data in aircraft communication and navigation bands are presented for several active radio frequency identification (RFID) tags. The individual tags are different in design, operation and transmitting frequencies. The process for measuring the tags emissions in a reverberation chamber is discussed. Measurement issues dealing with tag interrogation, low level measurement in the presence of strong transmissions, and tags low duty factors are discussed. The results show strong emissions, far exceeding aircraft emission limits and can be of potential interference risks.

  16. The broad-band radio spectrum of LSI+61303 in outburst

    CERN Document Server

    Zimmermann, L; Massi, M

    2015-01-01

    Aims: Our aim is to explore the broad-band radio continuum spectrum of LSI+61303 during its outbursts by employing the available set of secondary focus receivers of the Effelsberg 100 m telescope. Methods: The clear periodicity of the system LSI+61303 allowed observations to be scheduled covering the large radio outburst in March-April 2012. We observed LSI+61303 on 14 consecutive days at 2.6, 4.85, 8.35, 10.45, 14.3, 23, and 32 GHz with a cadence of about 12 hours followed by two additional observations several days later. Based on these observations we obtained a total of 24 quasi-simultaneous broad-band radio spectra. Results: During onset, the main flare shows an almost flat broad-band spectrum, most prominently seen on March 27, 2012, where - for the first time - a flat spectrum (alpha=0.00+/-0.07, S nu^alpha) is observed up to 32 GHz (9 mm wavelength). The flare decay phase shows superimposed 'sub-flares' with the spectral index oscillating between -0.4 and -0.1 in a quasi-regular fashion. Finally, the ...

  17. Spectrum Band Selection in Delay-QoS Constrained Cognitive Radio Networks

    KAUST Repository

    Yang, Yuli

    2014-01-01

    In this paper, a cognitive radio (CR) network with multiple spectrum bands available for secondary users (SUs) is considered. For the SU\\'s active spectrum-band selection, two criteria are developed. One is to select the band with the highest secondary channel power gain, and the other is to select the band with the lowest interference channel power gain to primary users (PUs). With the quality-of-service (QoS) requirement concerning delay, the effective capacity (EC) behaviors over secondary links are investigated for both criteria under two spectrum-sharing constraints. To begin by presenting full benefits in these criteria, the constraint imposed on the secondary transmitter (ST) is the average interference limitation to PUs only. Furthermore, taking into account the ST\\'s battery/energy budget, the ST is imposed by joint constraints on its average interference to PUs, as well as on its own average transmit power. For either constraint, we formulate the ST\\'s optimal transmit power allocation to maximize the SU\\'s EC with both band-selection criteria and, correspondingly, obtain the secondary\\'s power allocation and maximum EC in closed forms. Numerical results demonstrated subsequently substantiate the validity of our derivations and provide a powerful tool for the spectrum-band selection in CR networks with multiple bands available. © 1967-2012 IEEE.

  18. An Eight Element S-Band Antenna Array for Evaluating Directional Mesh Networking Using Software Definded Radios

    Science.gov (United States)

    2014-12-01

    AN EIGHT ELEMENT S-BAND ANTENNA ARRAY FOR EVALUATING DIRECTIONAL MESH NETWORKING USING SOFTWARE DEFINED RADIOS DECEMBER 2014 TECHNICAL REPORT...EVALUATING DIRECTIONAL MESH NETWORKING USING SOFTWARE DEFINED RADIOS 5a. CONTRACT NUMBER IN-HOUSE 5b. GRANT NUMBER N/A 5c. PROGRAM ELEMENT NUMBER...band linear array antenna intended for use in investigation directional mesh networks is presented. Results of the development activities are presented

  19. Wide-Band, Low-Frequency Pulse Profiles of 100 Radio Pulsars with LOFAR

    CERN Document Server

    Pilia, M; Stappers, B W; Kondratiev, V I; Kramer, M; van Leeuwen, J; Weltevrede, P; Lyne, A G; Zagkouris, K; Hassall, T E; Bilous, A V; Breton, R P; Falcke, H; Grießmeier, J -M; Keane, E; Karastergiou, A; Kuniyoshi, M; Noutsos, A; Osłowski, S; Serylak, M; Sobey, C; ter Veen, S; Alexov, A; Anderson, J; Asgekar, A; Avruch, I M; Bell, M E; Bentum, M J; Bernardi, G; Bîrzan, L; Bonafede, A; Breitling, F; Broderick, J W; Brüggen, M; Ciardi, B; Corbel, S; de Geus, E; de Jong, A; Deller, A; Duscha, S; Eislöffel, J; Fallows, R A; Fender, R; Ferrari, C; Frieswijk, W; Garrett, M A; Gunst, A W; Hamaker, J P; Heald, G; Horneffer, A; Jonker, P; Juette, E; Kuper, G; Maat, P; Mann, G; Markoff, S; McFadden, R; McKay-Bukowski, D; Miller-Jones, J C A; Nelles, A; Paas, H; Pandey-Pommier, M; Pietka, M; Pizzo, R; Polatidis, A G; Reich, W; Röttgering, H; Rowlinson, A; Schwarz, D; Smirnov, O; Steinmetz, M; Stewart, A; Swinbank, J D; Tagger, M; Tang, Y; Tasse, C; Thoudam, S; Toribio, M C; van der Horst, A J; Vermeulen, R; Vocks, C; van Weeren, R J; Wijers, R A M J; Wijnands, R; Wijnholds, S J; Wucknitz, O; Zarka, P

    2015-01-01

    LOFAR offers the unique capability of observing pulsars across the 10-240 MHz frequency range with a fractional bandwidth of roughly 50%. This spectral range is well-suited for studying the frequency evolution of pulse profile morphology caused by both intrinsic and extrinsic effects: such as changing emission altitude in the pulsar magnetosphere or scatter broadening by the interstellar medium, respectively. The magnitude of most of these effects increases rapidly towards low frequencies. LOFAR can thus address a number of open questions about the nature of radio pulsar emission and its propagation through the interstellar medium. We present the average pulse profiles of 100 pulsars observed in the two LOFAR frequency bands: High Band (120-167 MHz, 100 profiles) and Low Band (15-62 MHz, 26 profiles). We compare them with Westerbork Synthesis Radio Telescope (WSRT) and Lovell Telescope observations at higher frequencies (350 and1400 MHz) in order to study the profile evolution. The profiles are aligned in abs...

  20. The control system of the 3 mm band SIS receiver for the Sardinia Radio Telescope

    Science.gov (United States)

    Ladu, A.; Ortu, P.; Saba, A.; Pili, M.; Guadiomonte, F.; Navarrini, A.; Urru, E.; Pisanu, T.; Valente, G.; Marongiu, P.; Mazzarella, G.

    2016-07-01

    We present the control system of the 84-116 GHz (3 mm band) Superconductor-Insulator-Superconductor (SIS) heterodyne receiver to be installed at the Gregorian focus of the Sardinia Radio Telescope (SRT). The control system is based on a single-board computer from Raspberry, on microcontrollers from Arduino, and on a Python program for communication between the receiver and the SRT antenna control software, which remotely controls the backshorttuned SIS mixer, the receiver calibration system and the Local Oscillator (LO) system.

  1. Finding a faint polarized signal in wide-band radio data

    CERN Document Server

    Schnitzeler, D H F M

    2016-01-01

    We develop two algorithms, based on maximum likelihood (ML) inference, for estimating the parameters of polarized radio sources which emit at a single rotation measure (RM), e.g., pulsars. These algorithms incorporate the flux density spectrum of the source, either a power law or a scaled version of the Stokes I spectrum, and a variation in sensitivity across the observing band. We quantify the detection significance and measurement uncertainties in the fitted parameters, and we derive weighted versions of the RM synthesis algorithm which, under certain conditions, maximize the likelihood. We use Monte Carlo simulations to compare injected and recovered source parameters for a range of signal-to-noise ratios, investigate the quality of standard methods for estimating measurement uncertainties, and search for statistical biases. These simulations consider one frequency band each for the Australia Telescope Compact Array (ATCA), the Square Kilometre Array (SKA), and the Low Frequency Array (LOFAR). We find that...

  2. Finding a faint polarized signal in wide-band radio data

    Science.gov (United States)

    Schnitzeler, D. H. F. M.; Lee, K. J.

    2017-04-01

    We develop two algorithms, based on maximum likelihood inference, for estimating the parameters of polarized radio sources which emit at a single rotation measure (RM), e.g. pulsars. These algorithms incorporate the flux density spectrum of the source, either a power law or a scaled version of the Stokes I spectrum, and a variation in sensitivity across the observing band. We quantify the detection significance and measurement uncertainties in the fitted parameters, and we derive weighted versions of the RM synthesis algorithm which, under certain conditions, maximize the likelihood. We use Monte Carlo simulations to compare injected and recovered source parameters for a range of signal-to-noise ratios, investigate the quality of standard methods for estimating measurement uncertainties and search for statistical biases. These simulations consider one frequency band each for the Australia Telescope Compact Array, the Square Kilometre Array (SKA) and the Low Frequency Array. We find that results obtained for one frequency band cannot be easily generalized, and that methods that were developed in the past for correcting bias in individual frequency channels do not apply to wide-band data sets. The standard method for estimating the measurement uncertainty in RM is not accurate for sources with non-zero spectral indices. Furthermore, dividing Stokes Q and U by Stokes I to correct for spectral index effects, in combination with RM synthesis, does not maximize the likelihood.

  3. Multi-Band (K- Q- and E-Band) Multi-Tone Millimeter-Wave Frequency Synthesizer for Radio Wave Propagation Studies

    Science.gov (United States)

    Simons, Rainee N.; Wintucky, Edwin G.

    2014-01-01

    This paper presents the design and test results of a multi-band multi-tone millimeter-wave frequency synthesizer, based on a solid-state frequency comb generator. The intended application of the synthesizer is in a space-borne transmitter for radio wave atmospheric studies at K-band (18 to 26.5 GHz), Q-band (37 to 42 GHz), and E-band (71 to 76 GHz). These studies would enable the design of robust multi-Gbps data rate space-to-ground satellite communication links. Lastly, the architecture for a compact multi-tone beacon transmitter, which includes a high frequency synthesizer, a polarizer, and a conical horn antenna, has been investigated for a notional CubeSat based space-to-ground radio wave propagation experiment.

  4. Search for molecular bremsstrahlung radiation signals in Ku band with coincidental operations of radio telescopes with air shower detectors

    Directory of Open Access Journals (Sweden)

    Fukushima Masaki

    2013-06-01

    Full Text Available Microwave radiation from extensive air showers is expected to provide a new technique to observe UHECR. We insatlled and operate radio telescopes in Osaka and at Telescope Array site in Utah, USA. In Osaka, we are coincidentally operating two Ku band radio telescopes with an air shower array which consists of nine plastic scintillators with about 10 m separation. In Utah, we installed two telescopes just beside the Black Rock Mesa fluorescence detector (FD station of the Telescope Array experiment, and we operated the radio telescopes coincidentally with FD event triggers. We report the experimental setups and the results of these measurements.

  5. Design of Novel S-Shaped Quad-Band Antenna for MedRadio/WMTS/ISM Implantable Biotelemetry Applications

    OpenAIRE

    2012-01-01

    A novel S-shaped quad-band planar inverted-F antenna (PIFA) is proposed for implantable biotelemetry in the Medical Device Radiocommunications Service (MedRadio) band (401–406 MHz), Wireless Medical Telemetry Service (WMTS) band (1427–1432 MHz), and industrial, scientific, and medical (ISM) bands (433-434 MHz and 2.4–2.4835 GHz). The proposed antenna reveals compact dimension of 254 mm3 (10×10×2.45 mm3) and is composed of three substrates and a superstrate, which are constructed from an S-sha...

  6. Large Scale Assessment of Radio Frequency Interference Signatures in L-band SAR Data

    Science.gov (United States)

    Meyer, F. J.; Nicoll, J.

    2011-12-01

    Imagery of L-band Synthetic Aperture Radar (SAR) systems such as the PALSAR sensor on board the Advanced Land Observing Satellite (ALOS) has proven to be a valuable tool for observing environmental changes around the globe. Besides offering 24/7 operability, the L-band frequency provides improved interferometric coherence, and L-band polarimetric data has shown great potential for vegetation monitoring, sea ice classification, and the observation of glaciers and ice sheets. To maximize the benefit of missions such as ALOS PALSAR for environmental monitoring, data consistency and calibration are vital. Unfortunately, radio frequency interference (RFI) signatures from ground-based radar systems regularly impair L-band SAR data quality and consistency. With this study we present a large-scale analysis of typical RFI signatures that are regularly observed in L-band SAR data over the Americas. Through a study of the vast archive of L-band SAR data in the US Government Research Consortium (USGRC) data pool at the Alaska Satellite Facility (ASF) we were able to address the following research goals: 1. Assessment of RFI Signatures in L-band SAR data and their Effects on SAR Data Quality: An analysis of time-frequency properties of RFI signatures in L-band SAR data of the USGRC data pool is presented. It is shown that RFI-filtering algorithms implemented in the operational ALOS PALSAR processor are not sufficient to remove all RFI-related artifacts. In examples, the deleterious effects of RFI on SAR image quality, polarimetric signature, SAR phase, and interferometric coherence are presented. 2. Large-Scale Assessment of Severity, Spatial Distribution, and Temporal Variation of RFI Signatures in L-band SAR data: L-band SAR data in the USGRC data pool were screened for RFI using a custom algorithm. Per SAR frame, the algorithm creates geocoded frame bounding boxes that are color-coded according to RFI intensity and converted to KML files for analysis in Google Earth. From

  7. Simulation Platform for Wireless Sensor Networks Based on Impulse Radio Ultra Wide Band

    CERN Document Server

    Berthe, Abdoulaye; Dragomirescu, Daniela; Plana, Robert

    2010-01-01

    Impulse Radio Ultra Wide Band (IR-UWB) is a promising technology to address Wireless Sensor Network (WSN) constraints. However, existing network simulation tools do not provide a complete WSN simulation architecture, with the IR-UWB specificities at the PHYsical (PHY) and the Medium Access Control (MAC) layers. In this paper, we propose a WSN simulation architecture based on the IR-UWB technique. At the PHY layer, we take into account the pulse collision by dealing with the pulse propagation delay. We also modelled MAC protocols specific to IRUWB, for WSN applications. To completely fit the WSN simulation requirements, we propose a generic and reusable sensor and sensing channel model. Most of the WSN application performances can be evaluated thanks to the proposed simulation architecture. The proposed models are implemented on a scalable and well known network simulator: Global Mobile Information System Simulator (GloMoSim). However, they can be reused for all other packet based simulation platforms.

  8. Comparing On-Orbit and Ground Performance for an S-Band Software-Defined Radio

    Science.gov (United States)

    Chelmins, David T.; Welch, Bryan W.

    2014-01-01

    NASA's Space Communications and Navigation Testbed was installed on an external truss of the International Space Station in 2012. The testbed contains several software-defined radios (SDRs), including the Jet Propulsion Laboratory (JPL) SDR, which underwent performance testing throughout 2013 with NASAs Tracking and Data Relay Satellite System (TDRSS). On-orbit testing of the JPL SDR was conducted at S-band with the Glenn Goddard TDRSS waveform and compared against an extensive dataset collected on the ground prior to launch. This paper will focus on the development of a waveform power estimator on the ground post-launch and discuss the performance challenges associated with operating the power estimator in space.

  9. DVB-RCS return link radio resource management for broadband satellite systems using fade mitigation techniques at ka band

    OpenAIRE

    2008-01-01

    Current Broadband Satellite systems supporting DVB-RCS at Ku band have static physical layer in order not to complicate their implementation. However at Ka band frequencies and above an adaptive physical layer wherein the physical layer parameters are dynamically modified on a per user basis is necessary to counteract atmospheric attenuation. Satellite Radio Resource Management (RRM) at the Medium Access Control (MAC) layer has become an important issue given the emphasis placed on Quality...

  10. IEEE 802.15.4 transceiver for the 868/915 MHz band using Software Defined Radio

    OpenAIRE

    Zitouni, Rafik; Ataman, Stefan; Mathian, Marie; George, Laurent

    2013-01-01

    This paper reports an implementation of the PHY specifications of the IEEE 802.15.4 standard for the frequency band 868 915 MHz on a Software Defined Radio (SDR) platform. This standard is defined for low power, low data rate and low cost wireless networks. These specifications are used by the Zigbee technology for various applications such as home automation, industry monitoring or medical surveillance. Several hardware PHY 868/915 MHz band IEEE 802.15.4 transceiver implementations have been...

  11. A Reconfigurable Triple-Notch-Band Antenna Integrated with Defected Microstrip Structure Band-Stop Filter for Ultra-Wideband Cognitive Radio Applications

    Directory of Open Access Journals (Sweden)

    Yingsong Li

    2013-01-01

    Full Text Available A printed reconfigurable ultra-wideband (UWB monopole antenna with triple narrow band-notched characteristics is proposed for cognitive radio applications in this paper. The triple narrow band-notched frequencies are obtained using a defected microstrip structure (DMS band stop filter (BSF embedded in the microstrip feed line and an inverted π-shaped slot etched in the rectangular radiation patch, respectively. Reconfigurable characteristics of the proposed cognitive radio antenna (CRA are achieved by means of four ideal switches integrated on the DMS-BSF and the inverted π-shaped slot. The proposed UWB CRA can work at eight modes by controlling switches ON and OFF. Moreover, impedance bandwidth, design procedures, and radiation patterns are presented for analysis and explanation of this antenna. The designed antenna operates over the frequency band between 3.1 GHz and 14 GHz (bandwidth of 127.5%, with three notched bands from 4.2 GHz to 6.2 GHz (38.5%, 6.6 GHz to 7.0 GHz (6%, and 12.2 GHz to 14 GHz (13.7%. The antenna is successfully simulated, fabricated, and measured. The results show that it has wide impedance bandwidth, multimodes characteristics, stable gain, and omnidirectional radiation patterns.

  12. Real-time dual-band wireless videos in millimeter-wave radio-over-fiber system

    Science.gov (United States)

    Cheng, Lin; Liu, Cheng; Dong, Ze; Wang, Jing; Zhu, Ming; Chang, Gee-Kung

    2013-12-01

    A dual-band converged radio-over-fiber (RoF) access system at 60-GHz and 100-GHz millimeter-wave (mm-wave) is proposed. Real-time end-to-end delivery of two channels of independent high-definition (HD) video services simultaneously carried on 60-GHz and 100-GHz radios is demonstrated for the first time. PRBS data transmission with equivalent data rate and format is also tested to characterize the system performance. The analysis of the spectrum from the beating signal indicates the entire 60-GHz band and the W-band can be retrieved without interference. The real-time HD video display and error-free (BER < 10-9) data transmission demonstrate the feasibility of the proposed wireless access system using converged fiber-optic and mm-wave RoF techniques.

  13. Stochastic relation between anomalous propagation in the line-of-sight VHF radio band and occurrences of earthquakes

    Directory of Open Access Journals (Sweden)

    K. Motojima

    2013-11-01

    Full Text Available This paper was intended to find out any relation between anomalous line-of-sight propagation on the VHF band and occurrences of earthquakes near the VHF propagation paths. The television and FM radio broadcasting waves on the VHF band were monitored continuously over the long term. For that purpose, a multidirectional VHF band monitoring system was established and utilized. Anomalous line-of-sight propagation on the VHF band was distinguished from the monitored wave by using a statistical analysis. After the stochastic consideration, it was found out that earthquakes associated with anomalous propagation were characterized by magnitude of earthquakes M ≥ 4.5, and distances from epicenters L ≤ 75 km. The anomalous propagation was monitored on the VHF band a few days earlier the associated earthquakes occurred. Moreover, the anomaly appeared on multidirectional propagation paths simultaneously. The anomaly on the line-of-sight propagation indicates possibility of narrow focusing the area of epicenter of earthquake.

  14. Wide-Band Spectra of Giant Radio Pulses from the Crab Pulsar

    CERN Document Server

    Mikami, Ryo; Tanaka, Shuta J; Kisaka, Shota; Sekido, Mamoru; Takefuji, Kazuhiro; Takeuchi, Hiroshi; Misawa, Hiroaki; Tsuchiya, Fuminori; Kita, Hajime; Yonekura, Yoshinori; Terasawa, Toshio

    2016-01-01

    We present the results of the simultaneous observation of the Giant Radio Pulses (GRPs) from the Crab pulsar at 0.3, 1.6, 2.2, 6.7 and 8.4 GHz with four telescopes in Japan. We obtain 3194 and 272 GRPs occurring at the main pulse and the interpulse phases, respectively. A few GRPs detected at both 0.3 and 8.4 GHz are the most wide-band samples ever reported. In the frequency range from 0.3 to 2.2 GHz, we find that about 70\\% or more of the GRP spectra are consistent with single power-laws and the spectral indices of them are distributed from $-4$ to $-1$. We also find that a significant number of GRPs have so hard spectral index $\\sim -1$) that the fluence at 0.3 GHz is below the detection limit (``dim-hard' GRPs). Stacking light curves of such dim-hard GRPs at 0.3 GHz, we detect consistent enhancement compared to the off-GRP light curve. Our samples show apparent correlations between the fluences and the spectral hardness, which indicates that more energetic GRPs tend to show softer spectra. Our comprehensiv...

  15. IMPULSE RADIO ULTRA WIDE BAND BASED MOBILE ADHOC NETWORK ROUTING PERFORMANCE ANALYSIS

    Directory of Open Access Journals (Sweden)

    M. Sreedhar

    2013-01-01

    Full Text Available This study presents with the routing overhead analysis of impulse radio - Ultra Wide Band based wireless networks which Employs Dynamic Nature Routing (EDNR method for determining and selecting the stable route in Mobile Adhoc Network (MANET. This method requires only two sample packets and uses piggyback information on Route-Request (RREQ and Route-Reply (RREP packets during a route-discovery procedure. Conventional ENDR results in better routing overhead and packet delivery ratio characteristics with higher energy consumption. The proposed method explores the characteristics of UWB nature of routing based on Node lifetime and Link lifetime prediction for reducing the required bandwidth while maintaining higher packet delivery and lower routing overhead. Simulation results illustrate the improvement of packet delivery ratio by 5% and reduction of routing overhead by 4.8% of the proposed UWB EDNR method over the conventional EDNR method. For higher packet delivery ratio and reduced routing overhead with efficient bandwidth utilization can be achieved by applying UWB based EDNR routing that is desired for real time data communications.

  16. Complexity-reduced digital predistortion for subcarrier multiplexed radio over fiber systems transmitting sparse multi-band RF signals.

    Science.gov (United States)

    Pei, Yinqing; Xu, Kun; Li, Jianqiang; Zhang, Anxu; Dai, Yitang; Ji, Yuefeng; Lin, Jintong

    2013-02-11

    A novel multi-band digital predistortion (DPD) technique is proposed to linearize the subcarrier multiplexed radio-over-fiber (SCM-RoF) system transmitting sparse multi-band RF signal with large blank spectra between the constituent RF bands. DPD performs on the baseband signal of each individual RF band before up-conversion and RF combination. By disregarding the blank spectra, the processing bandwidth of the proposed DPD technique is greatly reduced, which is only determined by the baseband signal bandwidth of each individual RF band, rather than the entire bandwidth of the combined multi-band RF signal. Experimental demonstration is performed in a directly modulated SCM-RoF system transmitting two 64QAM modulated OFDM signals on 2.4GHz band and 3.6GHz band. Results show that the adjacent channel power (ACP) is suppressed by 15dB leading to significant improvement of the EVM performances of the signals on both of the two bands.

  17. A theory for narrow-banded radio bursts at Uranus - MHD surface waves as an energy driver

    Science.gov (United States)

    Farrell, W. M.; Curtis, S. A.; Desch, M. D.; Lepping, R. P.

    1992-01-01

    A possible scenario for the generation of the narrow-banded radio bursts detected at Uranus by the Voyager 2 planetary radio astronomy experiment is described. In order to account for the emission burstiness which occurs on time scales of hundreds of milliseconds, it is proposed that ULF magnetic surface turbulence generated at the frontside magnetopause propagates down the open/closed field line boundary and mode-converts to kinetic Alfven waves (KAW) deep within the polar cusp. The oscillating KAW potentials then drive a transient electron stream that creates the bursty radio emission. To substantiate these ideas, Voyager 2 magnetometer measurements of enhanced ULF magnetic activity at the frontside magnetopause are shown. It is demonstrated analytically that such magnetic turbulence should mode-convert deep in the cusp at a radial distance of 3 RU.

  18. Experimental investigation on multi-dimensional digital predistortion for multi-band radio-over-fiber systems.

    Science.gov (United States)

    Chen, Hao; Li, Jianqiang; Xu, Kun; Pei, Yinqing; Dai, Yitang; Yin, Feifei; Lin, Jintong

    2014-02-24

    The recently-proposed multi-dimensional digital predistortion (DPD) technique is experimentally investigated in terms of nonlinearity order, memory length, oversampling rate, digital-to-analog conversion resolution, carrier frequency dependence and RF input power tolerance, in both directly-modulated and externally-modulated multi-band radio-over-fiber (RoF) systems. Similar characteristics of the multi-dimensional digital predistorter are identified in directly-modulated and externally-modulated RoF systems. The experimental results suggest implementing a memory-free multi-dimensional digital predistorter involving nonlinearity orders up to 5 at 2 × oversampling rate for practical multi-band RoF systems. Using the suggested parameters, the multi-dimensional DPD is able to improve the RF input power tolerance by greater than 3dB for each band in a two-band RoF system, indicating an enhancement of RF power transmitting efficiency.

  19. Radio Search for H2CCC toward HD 183143 as a Candidate for a Diffuse Interstellar Band Carrier

    CERN Document Server

    Araki, Mitsunori; Yamabe, Hiromichi; Tsukiyama, Koichi; Kuze, Nobuhiko

    2012-01-01

    To clarify the authenticity of a recently proposed identification of H2CCC (linear-C3H2) as a diffuse interstellar band carrier, we searched for the rotational transition of H2CCC at a frequency of 103 GHz toward HD 183143 using a 45-m telescope at the Nobeyama Radio Observatory. Although rms noise levels of 32 mK in the antenna temperature were achieved, detection of H2CCC was unsuccessful, producing a 3 sigma upper limit corresponding to a column density of 2.0 \\times 1013 cm-2. The upper limit indicates that the contribution of H2CCC to the diffuse interstellar band at 5450 {\\AA} is less than 1/25; thus, it is unlikely that the laboratory bands of the B1B1-X1A1 transition of H2CCC and the diffuse interstellar bands at 5450 {\\AA} (and also 4881 {\\AA}) toward HD 183143 are related.

  20. Reconfigurable radio access unit to dynamically distribute W-band signals in 5G wireless access networks

    DEFF Research Database (Denmark)

    Rodríguez Páez, Juan Sebastián; Rommel, Simon; Vegas Olmos, Juan José

    2017-01-01

    In this paper a new type of radio access unit is proposed and demonstrated. This unit is composed only of the reduced amount of components (compared to conventional unit designs) to optically generate wireless signals on the W-band (75–110 GHz) in combination with a switching system. The proposed...... system not only achieves BER values below the FEC limit, but gives an extra level of flexibility to the network by easing the redirection of the signal to different antennas....

  1. Temperature Effect on the Tropospheric Radio Signal Strength for UHF Band at Terengganu, Malaysia

    Directory of Open Access Journals (Sweden)

    Roshidah Mat

    2016-10-01

    Full Text Available In tropospheric layer, radio waves can propagate in a number of different physical mechanisms such as free-space propagation or line-of-sight propagation, reflection, transmission, diffraction, scattering and wave guiding. The constituents in weather such as the wind, air temperature and atmospheric water content may combine in many ways. Certain combinations can cause radio signals to be heard hundreds of miles beyond the ordinary range of radio communications. This study investigates the effect of weather (temperature on radio wave propagation up to 9GHz. Continuous-wave (CW envelope fading waveforms were recorded over a period of the one-hour using patch antenna. The observations were conducted at KUSZA Observatory, East Coast Environmental Research Institute (ESERI, UniSZA which is situated in Merang, Terengganu. Spectrum Analyser was used for RFI measurement and weather station for weather effect. The graphs of radio signal attenuation for weather parameter (temperature against time were plotted. The findings indicate that there is a relationship between radio signals with the change of temperature. The correlation between RFI frequencies and temperature give negative effect for frequency 945 MHz, was r = -0.085, while for 383 MHz (r = 0.249, 1800 MHz (r = 0.268 and 2160 MHz (r = 0.134. These findings will benefit radio wave propagation research field which includes radio astronomy observations, space science, wireless communication, satellite, antenna and mobile communication and also electromagnetic radiation (EMR research for health.

  2. Reconfigurable remote access unit for W-band Radio-over-Fiber transmission

    DEFF Research Database (Denmark)

    Chorchos, Łukasz; Rommel, Simon; Turkiewicz, Jarosław P.;

    2016-01-01

    There is a growing demand for cost-effective radio over fibre transmission techniques. In this paper, we propose and realize the reconfigurable remote access unit for radio-over-fiber transmission. The reconfigurable unit is build from the tunable filter and laser as well as remote controller. Su...

  3. 0.8-5.2GHz Broad-Band SiGe-MMIC Quadrature Mixer for Software Defined Radio Receiver

    Science.gov (United States)

    Murakami, Keishi; Suematsu, Noriharu; Tsutsumi, Koji; Kanazawa, Gakushi; Sekine, Tomotsugu; Kubo, Hiroshi; Isota, Yoji

    For the next generation wireless terminals used in the software defined radio (SDR), multi-band / multi-mode transceivers and their MMIC are required which cover the wide RF frequency range from several hundreds MHz up to several GHz. In this paper, 0.8-5.2GHz broad-band SiGe-MMIC quadrature mixer (Q-MIX) for multi-band / multi-mode direct conversion receiver has been developed. By using a static type frequency divider as a 90 degrees local (LO) power divider, measured error vector magnitude (EVM) of less than 3.1% can be achieved in the cases of 0.8/2.1GHz W-CDMA and 5.2GHz wireless Local Area Network (LAN) (IEEE 802.11a) reception. This Q-MIX also shows broad-band characteristic for base-band signal and is applicable for 4G cellular. By using fabricated Q-MIX, a multi-band / multi-mode (1.9GHz (3rd generation cellular (W-CDMA)) / 5.2GHz (4th generation cellular (Multi-Carrier (MC)-CDMA))) receiver has been developed and it has firstly demonstrated the successful reception of motion picture via W-CDMA and MC-CDMA.

  4. Detection of significant cm to sub-mm band radio and gamma-ray correlated variability in Fermi bright blazars

    CERN Document Server

    Fuhrmann, L; Chiang, J; Angelakis, E; Zensus, J A; Nestoras, I; Krichbaum, T P; Ungerechts, H; Sievers, A; Pavlidou, V; Readhead, A C S; Max-Moerbeck, W; Pearson, T J

    2014-01-01

    The exact location of the gamma-ray emitting region in blazars is still controversial. In order to attack this problem we present first results of a cross-correlation analysis between radio (11 cm to 0.8 mm wavelength, F-GAMMA program) and gamma-ray (0.1-300 GeV) ~ 3.5 year light curves of 54 Fermi-bright blazars. We perform a source stacking analysis and estimate significances and chance correlations using mixed source correlations. Our results reveal: (i) the first highly significant multi-band radio and gamma-ray correlations (radio lagging gamma rays) when averaging over the whole sample, (ii) average time delays (source frame: 76+/-23 to 7+/-9 days), systematically decreasing from cm to mm/sub-mm bands with a frequency dependence tau_r,gamma (nu) ~ nu^-1, in good agreement with jet opacity dominated by synchrotron self-absorption, (iii) a bulk gamma-ray production region typically located within/upstream of the 3 mm core region (tau_3mm,gamma=12+/-8 days), (iv) mean distances between the region of gamma-...

  5. An L-Band Radio Frequency Interference (RFI) Detection and Mitigation Testbed Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Radio Frequency Interference (RFI) can render microwave radiometer measurements useless. We have proposed a method and an architecture that can be used to identify...

  6. A C-Band Radio Frequency Interference (RFI) Detection and Mitigation Testbed Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Radio Frequency Interference (RFI) can render microwave radiometer measurements useless. We propose a method and an architecture that can be used to identify sources...

  7. A Multi-Feed Receiver in the 18 to 26.5 GHz Band for Radio Astronomy

    Science.gov (United States)

    Orfei, A.; Carbonaro, L.; Cattani, A.; Cremonini, A.; Cresci, L.; Fiocchi, F.; Maccaferri, A.; Maccaferri, G.; Mariotti, S.; Monari, J.; Morsiani, M.; Natale, V.; Nesti, R.; Panella, D.; Poloni, M.; Roda, J.; Scalambra, A.; Tofani, G.

    2010-08-01

    A large-bandwidth, state-of-the-art multi-feed receiver has been constructed to be used on the new 64 m Sardinia Radio Telescope (SRT) (http://www.srt.inaf.itl), an antenna aiming to work from 300 MHz to 100 GHz with an almost continuous frequency coverage. The goal of this new receiver is to speed up the survey of the sky with high sensitivity in a frequency band that is very interesting to radio astronomers. In the meantime, the antenna erection has been finalized, and the receiver has been mounted on the Medicina 32 m antenna to be tested (http://www.med.ira.inaf.itl). We present a complete description of the system, including a dedicated backend, and the results of the tests.

  8. A Compact Novel Three-Port Integrated Wide and Narrow Band Antennas System for Cognitive Radio Applications

    Directory of Open Access Journals (Sweden)

    N. Anvesh Kumar

    2016-01-01

    Full Text Available The design of a three-port radiating structure, integrating wide and narrow band antennas for cognitive radio applications, is presented. It consists of a UWB antenna for spectrum sensing and two narrow band antennas for wireless communication integrated on the same substrate. The UWB antenna covers the complete UWB spectrum (3.1 GHz to 10.6 GHz approved by FCC. In the two narrow band antennas, each antenna presents dual bands. In particular, the first narrowband antenna resonates at 6.5 GHz, covering the frequency band between 6.36 GHz and 6.63 GHz, and at 9 GHz, covering the frequency band between 8.78 GHz and 9.23 GHz, presenting minimum return loss values of 28.3 dB at 6.5 GHz and 20.5 dB at 9 GHz, respectively. Similarly, the second one resonates at 7.5 GHz, covering the frequency band between 7.33 GHz and 7.7 GHz, and at 9.5 GHz, covering the frequency band between 9.23 GHz and 9.82 GHz, presenting minimum return loss values of 19.6 dB at 7.5 GHz and 28.8 dB at 9.5 GHz, respectively. Isolation among the three antennas is less than −20 dB over the UWB frequency spectrum. These antennas are realized on a FR4 substrate of dimensions 30 mm × 30 mm × 1.6 mm. Experimental results show a good agreement between the simulated and measured results.

  9. Impulse radio ultra wide-band over multi-mode fiber for in-home signal distribution

    DEFF Research Database (Denmark)

    Caballero Jambrina, Antonio; Rodes, Roberto; Jensen, Jesper Bevensee;

    2009-01-01

    We propose and experimentally demonstrate a high speed impulse radio ultra wide-band (IR-UWB) wireless link for in-home network signal distribution. The IR-UWB pulse is distributed over a multimode fiber to the transmitter antenna. Wireless transmitted bit-rates of 1 Gbps at 2 m and 2 Gbps at 1.5 m...... have successfully been demonstrated, with a simple envelope detection scheme. This system is remarkably simple and robust; this makes it very attractive for low-cost applications in short range high-speed wireless links with low radiated power....

  10. Radio Search for H2CCC toward HD 183143 as a Candidate for a Diffuse Interstellar Band Carrier

    Science.gov (United States)

    Araki, Mitsunori; Takano, Shuro; Yamabe, Hiromichi; Tsukiyama, Koichi; Kuze, Nobuhiko

    2012-07-01

    To clarify the authenticity of a recently proposed identification of H2CCC (linear-C3H2) as a diffuse interstellar band (DIB) carrier, we searched for the rotational transition of H2CCC at a frequency of 103 GHz toward HD 183143 using the 45 m telescope at the Nobeyama Radio Observatory. Although rms noise levels of 32 mK in the antenna temperature were achieved, detection of H2CCC was unsuccessful, producing a 3σ upper limit corresponding to a column density of 2.0 × 1013 cm-2. The upper limit indicates that the contribution of H2CCC to the DIB at 5450 Å is less than 1/25; thus, it is unlikely that the laboratory bands of the B 1 B 1-X 1 A 1 transition of H2CCC and the DIBs at 5450 Å (and also 4881 Å) toward HD 183143 are related.

  11. PuMa-II: A wide band pulsar machine for the Westerbork Synthesis Radio Telescope

    NARCIS (Netherlands)

    Karuppusamy, R.; Stappers, B.; van Straten, W.

    2008-01-01

    The Pulsar Machine II (PuMa-II) is the new flexible pulsar processing back-end system at the Westerbork Synthesis Radio Telescope (WSRT), specifically designed to take advantage of the upgraded WSRT. The instrument is based on a computer cluster running the Linux operating system, with minimal custo

  12. The wideband backend at the MDSCC in Robledo. A new facility for radio astronomy at Q- and K- bands

    CERN Document Server

    Rizzo, J R; Gutiérrez, M; Sotuela, I; Larrañaga, J R; Ojalvo, L; Franco, M; Cernicharo, J; Miró, C García; Cerón, J M Castro; Kuiper, T B H; Vázquez, M; Calvo, J; Baquero, A

    2012-01-01

    The antennas of NASA's Madrid Deep Space Communications Complex (MDSCC) in Robledo de Chavela are available as single-dish radio astronomical facilities during a significant percentage of their operational time. Current instrumentation includes two antennas of 70 and 34 m in diameter, equipped with dual-polarization receivers in K (18 - 26 GHz) and Q (38 - 50 GHz) bands, respectively. We have developed and built a new wideband backend for the Robledo antennas, with the objectives (1) to optimize the available time and enhance the efficiency of radio astronomy in MDSCC; and (2) to tackle new scientific cases impossible to that were investigated with the old, narrow-band autocorrelator. The backend consists of an IF processor, a FFT spectrometer (FFTS), and the software that interfaces and manages the events among the observing program, antenna control, the IF processor, the FFTS operation, and data recording. The whole system was end-to-end assembled in August 2011, at the start of commissioning activities, an...

  13. On-glass automotive diversity antenna and LNA design for S-band satellite digital radio

    Science.gov (United States)

    Yeğin, Korkut

    2015-11-01

    Selection combining diversity system with antennas mounted on windshield and backlite of a vehicle is proposed for satellite digital audio radio applications. Standalone exterior mount antennas on metallic vehicles perform well for satellite digital audio radio applications, but for composite body vehicles or interior mount antennas, antenna performance becomes a real issue. Proposed on-glass two-antenna diversity is one solution for such applications. The antenna correlation is calculated using the S-parameters of the antennas and found to be very low due to many wavelengths separation between the antennas. Design of low noise amplifier, which has sub 1 dB noise figure and good P1dB due to strong cellular signals, is also detailed. A diversity receiver is described and ride tests are performed to assess the performance of the diversity system in real-time, under weak satellite signal environment which is regarded as the most challenging reception condition.

  14. Ka-Band Monopulse Antenna Pointing Calibration Using Wideband Radio Sources

    Science.gov (United States)

    Buu, C.; Calvo, J.; Cheng, T.-H.; Vazquez, M.

    2010-08-01

    A new method of performing a system end-to-end monopulse antenna calibration using widely available wideband astronomical radio sources is presented as an alternative to the current method of using a spacecraft signal. Current monopulse calibration requires a spacecraft carrier signal to measure amplitude and phase differences in the monopulse feed and low-noise amplifiers (LNAs). The alternative method presented here will allow the ground station to perform monopulse calibrations during maintenance periods instead of spacecraft track time, and provide an end-to-end system check-out capability without requiring a spacecraft signal. In this article, we give an overview of the current calibration approach, describe a new method for calibrating with radio sources, and present results from field testing of this new method.

  15. First results from the FPGA/NIOS Adaptive FIR Filter Using Linear Prediction Implemented in the AERA Radio Stations to Reduce Narrow Band RFI for Radio Detection of Cosmic Rays

    CERN Document Server

    Szadkowski, Zbigniew; Timmermans, C

    2014-01-01

    The FPGA/NIOS FIR filter based on linear prediction (LP) to suppress radio frequency interference (RFI) has been installed in several radio stations in the Auger Engineering Radio Array (AERA) experiment. AERA observes coherent radio emission from extensive air showers induced by ultra-high-energy cosmic rays to make a detailed study of the development of the electromagnetic part of air showers. Radio signals provide complementary information to that obtained from Auger surface detectors, which are predominantly sensitive to the particle content of an air shower at the surface. The radio signals from air showers are caused by the coherent emission due to geomagnetic and charge-excess processes. These emissions can be observed in the frequency band between 10 - 100 MHz. However, this frequency range is significantly contaminated by narrow-band RFI and other human-made distortions. A FIR filter implemented in the FPGA logic segment of the front-end electronics of a radio sensor significantly improves the signal...

  16. Spectrum Measurement and Analysis of TV Band in Support of Cognitive Radio Operation in India

    DEFF Research Database (Denmark)

    Patil, Kishor P.; Skouby, Knud Erik; Prasad, Ramjee

    2013-01-01

    TV White Spaces constitutes the major portion of the VHF and UHF TV band which is geographically unused after digital switchover. The most important regulatory trend in the context of Dynamic Spectrum Access (DSA) is the Cognitive access of TV white Spaces. Through spectrum measurement campaign we...

  17. Reconfigurable Radio Access Unit for DWDM to W-Band Wireless Conversion

    DEFF Research Database (Denmark)

    Chorchos, Łukasz; Rommel, Simon; Turkiewicz, Jarosław P.;

    2017-01-01

    In this letter a reconfigurable Remote Access Unit (RAU) is proposed and demonstrated, interfacing dense wavelength division multiplexed (DWDM) optical and W-band wireless links. The RAU is composed of a tunable local oscillator, a narrow optical filter and a control unit, making it reconfigurable...

  18. On the capacity of radio-over-fiber links at the W-band

    DEFF Research Database (Denmark)

    Cavalcante, Lucas Costa Pereira; Rommel, Simon; Rodríguez Páez, Juan Sebastián

    2016-01-01

    provide a set of trade-off maps in terms of crucial resources on the design of W-band RoF links. The proposed framework offers a unified view for answering how fundamental spectrum resources can be optimally utilized, and how far we are from overcoming the challenge of offering seamless convergence...

  19. Instant Radio Spectra of Giant Pulses from the Crab Pulsar Over Decimeter to Decameter Wave Band

    Science.gov (United States)

    Popov, M. V.; Kuzmin, A. D.; Ulyanov, O. M.; Deshpande, A. A.; Ershov, A. A.; Kondratiev, V. I.; Kostyuk, S. V.; Losovsky, B. Ya.; Soglasnov, V. A.; Zakharenko, V. V.

    2006-08-01

    We present results of simultaneous multi-frequency observations of giant radio pulses (GPs) from the Crab pulsar PSR B0531+21 at frequencies of 23, 111 and 600 MHz. For the first time GPs were detected at such low frequency as 23 MHz. Among 45 GPs detected in the overall observations time with 600 MHz, 12 GPs were identified as simultaneous ones at 600 and 23 MHz. At 111 MHz among 128 GPs detected in the overall observations time with 600 MHz, 21 GPs were identified as simultaneous ones at 600 and 111 MHz. Spectral indexes for the power-law frequency dependence of GPs energy were enclosed between -3.1 and -1.6. Mean spectral index equals to -2.7 ± 0.1 and is the same for both frequency combinations 600-111 MHz and 600-23 MHz. A big scatter in values of the individual spectral indexes and a large number of unidentified giant pulses, indicate that a real form of spectra of individual giant pulses does not follow a simple power law. The shape of giant pulses at all three frequencies is governed by the scattering of radio waves on the inhomogeneities of the interstellar plasma. The pulse scatter broadening and their frequency dependence was measured as τ[SC]=20(ν/100)^-3.5^±^0.1 ms, where frequency ν is in MHz. The main results of these observations are present on the figure bellow.

  20. Confirmation of a conspiracy - Dual-band VLBI maps of the flat-spectrum radio source 2021 + 614

    Science.gov (United States)

    Wittels, J. J.; Shapiro, I. I.; Cotton, W. D.

    1982-01-01

    VLBI observations at 3.6 and 13 cm wavelengths of the flat-spectrum radio source 2021 + 614 reveal two components, separated by about 6.5 + or - 0.6 milli-arcseconds along a position angle of 36 deg + or - 6 deg. The dual-band observations show that the two components have spectral indices of opposite signs, indicating that, as for 0735 + 178 (Cotton et al. 1980), the flat spectrum of 2021 + 614 is a result of the superposition of spectra from individual components, each having a peaked spectrum, presumably due to incoherent electron synchrotron radiation. If this situation is typical, then there is too large a percentage of flat-spectrum sources for the individual components in each to have independent characteristics.

  1. Note: radio frequency inductance-capacitance band-stop filter circuit to perform contactless conductivity measurements in pulsed magnetic fields.

    Science.gov (United States)

    Altarawneh, M M

    2012-09-01

    We present a new technique to perform radio frequency (rf) contactless conductivity measurements in pulsed magnetic fields to probe different ground states in condensed matter physics. The new method utilizes a simple analog band-stop filter circuit implemented in a radio frequency transmission setup to perform contactless conductivity measurements. The new method is more sensitive than the other methods (e.g., the tunnel diode oscillator and the proximity detector oscillator) due to more sensitive dependence of the circuit resonance frequency on the tank circuit inductance (not the transmission line). More important, the new method is more robust than other methods when used to perform measurements in very high magnetic fields, works for a wide range of temperatures (i.e., 300 K-1.4 K) and is less sensitive to noise and mechanical vibrations during pulse magnet operation. The new technique was successfully applied to measure the Shubnikov-de Haas effect in Bi(2)Se(3) in pulsed magnetic fields of up to 60 T.

  2. Dynamic control approaches of spectrum sensing in multi-band cognitive radio networks

    Institute of Scientific and Technical Information of China (English)

    AN Chun-yan; JI Hong; SI Peng-bo; MAO Xu

    2010-01-01

    In this paper,the dynamic control approaches for spectrum sensing are proposed,based on the theory that prediction is synonymous with data compression in computational learning. Firstly,a spectrum sensing sequence prediction scheme is proposed to reduce the spectrum sensing time and improve the throughput of secondary users. We use Ziv-Lempel data compression algorithm to design the prediction scheme,where spectrum band usage history is utilized. In addition,an iterative algorithm to find out the optimal number of spectrum bands allowed to sense is proposed,with the aim of maximizing the expected net reward of each secondary user in each time slot. Finally,extensive simulation results are shown to demonstrate the effectiveness of the proposed dynamic control approaches of spectrum sensing.

  3. Radio frequency fields generated by the S-band communication link on OV102

    Science.gov (United States)

    Murphy, G. B.; Shawhan, S. D.

    1984-01-01

    The Space Shuttle STS-3 mission carried a Plasma Diagnostics Package (PDP) whose instrumentation included an S-band antenna and detector. The PDP was maneuvered by the Remote Manipulator System arm through a computer controlled sequence in the Orbiter's X-Z plane, above the quad and hemi S-band communications antennas. Antenna field strength measurements were conducted during transmitter high power modes, and the results were compared to ground full scale measurements and predictions. A field strength 4.8 + or - 3 dB higher than predicted is noted. This RF field is primarily due to the quad PM transmitter, whose power output of 115 W compares with 15 W for the hemi.

  4. C and L band transionospheric scintillation experiment - Some results for applications to satellite radio systems

    Science.gov (United States)

    Banerjee, P. K.; Dabas, R. S.; Reddy, B. M.

    1992-12-01

    The signal statistics of some scintillation events at the C/L bands are estimated for the high solar activity period of solar cycle 22 at a low-latitude station in the Indian zone. In addition to the morphology at 4 Ghz, data on signal statistics such as the cumulative amplitude distribution function, fade rate distribution, and signal reliability for different message lengths for some events of scintillations, both at C and L band, are presented. The theoretical Nakagami m distribution is found to be the best for describing various levels of fade. Autocorrelation and power-spectrum analysis are used to estimate average fade rates and ground correlation distances. Performance evaluation of satellite earth terminals using small antennas is carried out to show the vulnerability of the system in the hostile ionospheric environment, notwithstanding the advanced modulation systems being employed.

  5. Gamma-ray bursts from massive Population III stars: clues from the radio band

    CERN Document Server

    Burlon, D; Ghirlanda, G; Hancock, P J; Parry, R; Salvaterra, R

    2016-01-01

    Current models suggest gamma-ray bursts could be used as a way of probing Population III stars - the first stars in the early Universe. In this paper we use numerical simulations to demonstrate that late time radio observations of gamma-ray burst afterglows could provide a means of identifying bursts that originate from Population III stars, if these were highly massive, independently from their redshift. We then present the results from a pilot study using the Australia Telescope Compact Array at 17 GHz, designed to test the hypothesis that there may be Population III gamma-ray bursts amongst the current sample of known events. We observed three candidates plus a control gamma-ray burst, and make no detections with upper limits of 20-40 uJy at 500-1300 days post explosion.

  6. Gamma-ray bursts from massive Population-III stars: clues from the radio band

    Science.gov (United States)

    Burlon, D.; Murphy, T.; Ghirlanda, G.; Hancock, P. J.; Parry, R.; Salvaterra, R.

    2016-07-01

    Current models suggest gamma-ray bursts could be used as a way of probing Population-III stars - the first stars in the early Universe. In this paper, we use numerical simulations to demonstrate that late-time radio observations of gamma-ray burst afterglows could provide a means of identifying bursts that originate from Population-III stars, if these were highly massive, independently from their redshift. We then present the results from a pilot study using the Australia Telescope Compact Array at 17 GHz, designed to test the hypothesis that there may be Population-III gamma-ray bursts amongst the current sample of known events. We observed three candidates plus a control gamma-ray burst, and make no detections with upper limits of 20-40 μJy at 500-1300 d post-explosion.

  7. An electrodeless system for measurement of liquid sample dielectric properties in radio frequency band.

    Science.gov (United States)

    Hartwig, V; Giovannetti, G; Vanello, N; Costantino, M; Landini, L; Benassi, A

    2006-01-01

    An electrodeless measurement system based on a resonant circuit is proposed for the measurement of dielectric properties of liquid samples at RF (radio frequency). Generally, properties as dielectric constant, loss factor and conductivity are measured by parallel plate capacitor cells: this method has several limitations in the case of particular liquid samples and in the range of radiofrequencies. Our method is based on the measurements of resonance frequency and quality factor of a LC resonant circuit in different measuring conditions, without and with the liquid sample placed inside a test tube around which the home made coil is wrapped. The measurement is performed using a network analyzer and a dual loop probe, inductively coupled with the resonant circuit. One of the advantages of this method is the contactless between the liquid sample and the measurement electrodes. In this paper the measurement system is described and test measurements of conventional liquids dielectric properties are reported.

  8. Citizen's Report

    Data.gov (United States)

    Office of Personnel Management — The fiscal year (FY) 2008 Citizen's Report is a summary of performance and financial results for the U.S. Office of Personnel Management (OPM). OPM chose to produce...

  9. Five years of Project META - An all-sky narrow-band radio search for extraterrestrial signals

    Science.gov (United States)

    Horowitz, Paul; Sagan, Carl

    1993-01-01

    We have conducted a five-year search of the northern sky (delta between 30 and 60 deg) for narrow-band radio signals near the 1420 MHz line of neutral hydrogen, and its second harmonic, using an 8.4 x 10 exp 6 channel Fourier spectrometer of 0.05 Hz resolution and 400 kHz instantaneous bandwidth. The observing frequency was corrected both for motions with respect to three astronomical inertial frames, and for the effect of Earth's rotation, which provides a characteristic changing Doppler signature for narrow-band signals of extraterrestrial origin. Among the 6 x 10 exp 13 spectral channels searched, we have found 37 candidate events exceeding the average detection threshold of 1.7 x 10 exp -23 W/sq m, none of which was detected upon reobservation. The strongest of these appear to be dominated by rare processor errors. However, the strongest signals that survive culling for terrestrial interference lie in or near the Galactic plane. We describe the search and candidate events, and set limits on the prevalence of supercivilizations transmitting Doppler-precompensated beacons at H I or its second harmonic. We conclude with recommendations for future searches, based upon these findings, and a description of our next-generation search system.

  10. New 60-cm Radio Survey Telescope with the Sideband-Separating SIS Receiver for the 200 GHz Band

    CERN Document Server

    Nakajima, Taku; Korogi, Jun; Kimura, Kimihiro; Yonekura, Yoshinori; Ogawa, Hideo; Nishiura, Shingo; Dobashi, Kazuhito; Handa, Toshihiro; Kohno, Kotaro; Morino, Jun-Ichi; Asayama, Shin'ichiro; Noguchi, Takashi

    2007-01-01

    We have upgraded the 60-cm radio survey telescope located in Nobeyama, Japan. We developed a new waveguide-type sideband-separating SIS mixer for the telescope, which enables the simultaneous detection of distinct molecular emission lines both in the upper and lower sidebands. Over the RF frequency range of 205-240 GHz, the single-sideband receiver noise temperatures of the new mixer are 40-100 K for the 4.0-8.0 GHz IF frequency band. The image rejection ratios are greater than 10 dB over the same range. For the dual IF signals obtained by the receiver, we have developed two sets of acousto-optical spectrometers and a telescope control system. Using the new telescope system, we successfully detected the 12CO (J=2-1) and 13CO (J=2-1) emission lines simultaneously toward Orion KL in 2005 March. Using the waveguide-type sideband-separating SIS mixer for the 200 GHz band, we have initiated the first simultaneous 12CO (J=2-1) and 13CO (J=2-1) survey of the galactic plane as well as large-scale mapping observations...

  11. Ka-Band Link Study and Analysis for a Mars Hybrid RF/Optical Software Defined Radio

    Science.gov (United States)

    Zeleznikar, Daniel J.; Nappier, Jennifer M.; Downey, Joseph A.

    2014-01-01

    The integrated radio and optical communications (iROC) project at the NASA Glenn Research Center (GRC) is investigating the feasibility of a hybrid RF and optical communication subsystem for future deep space missions. The hybrid communications subsystem enables the advancement of optical communications while simultaneously mitigating the risk of infusion by combining an experimental optical transmitter and telescope with a reliable Ka-band RF transmitter and antenna. The iROC communications subsystem seeks to maximize the total data return over the course of a potential 2-year mission in Mars orbit beginning in 2021. Although optical communication by itself offers potential for greater data return over RF, the reliable Ka-band link is also being designed for high data return capability in this hybrid system. A daily analysis of the RF link budget over the 2-year span is performed to optimize and provide detailed estimates of the RF data return. In particular, the bandwidth dependence of these data return estimates is analyzed for candidate waveforms. In this effort, a data return modeling tool was created to analyze candidate RF modulation and coding schemes with respect to their spectral efficiency, amplifier output power back-off, required digital to analog conversion (DAC) sampling rates, and support by ground receivers. A set of RF waveforms is recommended for use on the iROC platform.

  12. Performance Evaluation of Impluse Radio Ultra Wide Band Wireless Sensor Networks

    CERN Document Server

    Lecointre, Aubin; Dragomirescu, Daniela; Plana, Robert

    2010-01-01

    This paper presents a performance evaluation of Wireless Sensor Networks (WSN) based on Impulse Radio Ultra Wideband (IR-UWB) over a new simulation platform developed for this purpose. The simulation platform is built on an existing network simulator: Global Mobile Information System Simulator (GloMoSim). It mainly focuses on the accurately modeling of IR-UWB PHYsical (PHY) and Medium Access Control (MAC) layer. Pulse collision is modeled according to the used time hopping sequence (THS) and the pulse propagation delay in order to increase the simulation fidelity. It also includes a detection and identification application based on a new sensing channel and new sensor device models. The proposed architecture is generic so it can be reused for any simulation platform. The performance evaluation is based on one of the typical WSN applications: local area protection, where sensor nodes are densely scattered in an access regulated area in order to detect, identify and report non authorized accesses to a base stat...

  13. Impact of tropospheric scintillation in the Ku/K bands on the communications between two LEO satellites in a radio occultation geometry

    DEFF Research Database (Denmark)

    Martini, Enrica; Freni, A.; Facheris, L.

    2006-01-01

    A theoretical analysis of the impact of clear-air tropospheric scintillation on a radio occultation link between two low Earth orbit satellites in K- and Ku-bands is presented, with particular reference to differential approaches for the measure of the total content of water vapor. The troposphere...

  14. STUDY OF RADIO DEVICES ON 2.4GHZ ISM BAND IN PHYSICAL PHASE

    Institute of Scientific and Technical Information of China (English)

    Li Li

    2008-01-01

    In the unlicensed 2.4GHz ISM band,there is not only IEEE 802.11 wireless systems being used,but also some other devices,such as residential microwave oven,Bluetooth devices,and cordless phone.All these devices that are not used for the data communications cause unintentional interference that will degrade the WI-FI system.In this paper,the transmission powers for common RF devices are measured and the SIR (signal-to-interference ratio) of different interferers to Wi-Fi is also studied.With this information,the effect of different interference on WI-FI signal can hence be quantified.Furthermore,the ability of the interference avoidance protocols,which is built into the AEto address interference problems caused by that device is determined.

  15. First Beam Measurements of the S-Band photocathode Radio-Frequency Gun at Tsinghua University

    Institute of Scientific and Technical Information of China (English)

    DU Ying-Chao; YAN Li-Xin; DU Qiang; HE Xiao-Zhong; XIANG Dao; TANG Chuan-Xiang; HUANG Wen-Hui; LIN Yu-Zheng

    2007-01-01

    During the last decades, photocathode rfgun has been proven to be successful in generating the high brightness electron beam (~1nC,~1πmmmrad,~1 ps) which is required by the ILC, XFEL, Thomson scattering x-ray source,etc. A photocathode rf gun system is built to develop electron source for the Thomson scattering x-ray source at Accelerator Laboratory of Tsinghua University. The system consists of a BNL/ATF-type 1.6 cell S-band rf cavity, a solenoid for emittance compensation, a laser system and some simple equipments for beam diagnosis.The first beam measurements of the photocathode rf gun, including the dark current, transverse beam profile,charge and quantum efficiency, are reported.

  16. A 3mm band dual polarization MMIC receiver for the 30-m Pico Veleta Radio Telescope

    Science.gov (United States)

    Serres, Patrice; Garnier, Olivier; Bortolotti, Yves; Navarro, Santiago; John, Dave; Pissard, Bruno; Navarrini, Alessandro; Schuster, Karl F.

    2012-09-01

    We present the design, construction and test results of a prototype MMIC receiver for the 3 mm band (84-116 GHz). The receiver cryogenic module consists of a single corrugated feed horn cascaded with an Ortho Mode Traducer (OMT) that splits the two incoming linear polarized signals in two independent single-mode rectangular waveguides. Low noise MMIC HEMT amplification modules, attached to the OMT WR10 waveguide outputs, amplify the signal of each polarization channel. Outside the dewar, each signal is filtered, down-converted, and further amplified to provide a final 8 GHz IF bandwidth across 4-12 GHz. The receiver was installed on the Pico Veleta 30 m telescope in August 2010 where it was used to perform spectral line surveys of astronomical sources. The measured receiver noise temperature was below 75 K with an average value of ~55 K for both polarization channels across 84-116 GHz.

  17. STUDY OF RADIO DEVICES ON 2.4GHZ ISM BAND IN PHYSICAL PHASE

    Institute of Scientific and Technical Information of China (English)

    Li Li

    2008-01-01

    In the unlicensed 2.4GHz ISM band,there is not only IEEE 802.11 wireless systems being used,but also some other devices,such as residential microwave oven,Bluetooth devices,and cordless phone.All these devices that are not used for the data communications cause unintentional interference that will degrade the WI-FI system.In this paper,the transmission powers for common RF devices are measured and the SIR(signal-to-interference ratio)of different interferers to Wi-Fi is also studied.With this information,the effect of different interlerence on WI-FI signal can hence be quantified.Furthermore,the ability of the interference avoidance protocols,which is built into the AP,to address interference problems caused by that device is determined.

  18. Studying integrated silicon-lens antennas for radio communication systems operated in the 60 GHz frequency band

    Science.gov (United States)

    Artemenko, A. A.; Mal'tsev, A. A.; Maslennikov, R. O.; Sevastyanov, A. G.; Ssorin, V. N.

    2013-01-01

    We consider the development of an integrated lens antenna for LAN radio communication systems operated in the 60 GHz frequency band. The antenna is an extended hemispherical silicon lens. On its flat surface, a microstrip antenna element is located. The use of silicon, which has a dielectric permittivity ɛ = 11.7, as the lens material ensures the maximum range of scanning angles for the minimum axial size of the lens. The approximate analytical formulas, which are used for initial calculations of the lens parameters, allow one to evaluate the basic parameters of the lens antenna integrated with the microstrip antenna element. For further optimizing the parameters of the lens and the antenna element, 3D simulation of the electromagnetic-field distribution was performed. Based on its results, we have developed and manufactured extended hemispherical silicon lenses, which had radii of 6 and 12 mm. The planar microstrip antenna element was manufactured by the low temperature co-fired ceramics (LTCC) technology. The results of simulation and experimental studies of the manufactured prototypes demonstrate that the developed lens antennas has directivities of 17.6 and 23.1 dBi for lenses with radii of 6 and 12 mm, respectively. In this case, the maximum beam deflection angle is achieved, which is equal to 55°, while the permissible decrease in the directivity is no more than 6 dBi compared with the case of a non-deflected beam. The obtained results show that the developed integrated lens antennas can find applications in high-speed radio communication systems operated in the millimeter-wave range.

  19. Practical Limits in the Sensitivity-Linearity Trade-off for Radio Telescope Front Ends in the HF and VHF-low Bands

    CERN Document Server

    Tillman, R H; Brendler, J

    2016-01-01

    Radio telescope front ends must have simultaneously low noise and sufficiently-high linearity to accommodate interfering signals. Typically these are opposing design goals. For modern radio telescopes operating in the HF (3-30 MHz) and VHF-low (30-88 MHz) bands, the problem is more nuanced in that front end noise temperature may be a relatively small component of the system temperature, and increased linearity may be required due to the particular interference problems associated with this spectrum. In this paper we present an analysis of the sensitivity-linearity trade off at these frequencies, applicable to existing commercially-available monolithic microwave integrated circuit (MMIC) amplifiers in single-ended, differential, and parallelized configurations. This analysis and associated findings should be useful in the design and upgrade of front ends for low frequency radio telescopes. The analysis is demonstrated explicitly for one of the better-performing amplifiers encountered in this study, the Mini-Ci...

  20. Low-cost approach for a software-defined radio based ground station receiver for CCSDS standard compliant S-band satellite communications

    Science.gov (United States)

    Boettcher, M. A.; Butt, B. M.; Klinkner, S.

    2016-10-01

    A major concern of a university satellite mission is to download the payload and the telemetry data from a satellite. While the ground station antennas are in general easy and with limited afford to procure, the receiving unit is most certainly not. The flexible and low-cost software-defined radio (SDR) transceiver "BladeRF" is used to receive the QPSK modulated and CCSDS compliant coded data of a satellite in the HAM radio S-band. The control software is based on the Open Source program GNU Radio, which also is used to perform CCSDS post processing of the binary bit stream. The test results show a good performance of the receiving system.

  1. Tracking galaxy evolution through low frequency radio continuum observations using SKA and Citizen-science Research using Multi-wavelength data

    CERN Document Server

    Hota, Ananda; Stalin, C S; Vaddi, Sravani; Mohanty, Pradeepta K; Dabhade, Pratik; Bhoga, Sai Arun Dharmik; Rajoria, Megha; Sethi, Sagar

    2016-01-01

    We present a review on galaxy black hole co-evolution through merger, star formation and AGN-jet feedback. We highlight results on transitional galaxies (e.g. NGC1482, NGC6764, NGC3801, Speca, RAD-18 etc.) which has data from Giant Meterwave Radio Telescope (GMRT) and other sub-mm, IR, optical, UV and X-ray telescopes. The `smoking gun' relic-evidences of past AGN-jet feedback which is believed to have quenched star formation in transitional galaxies are still missing. Relic radio lobes, as old as a few hundred Myr, can be best detected at low radio frequencies with the GMRT, LOFAR and in future SKA. However, similar relic evidences of quasar activities, known as `Hanny's Voorwerp' discovered by Galaxy Zoo in optical data, are only around a few tens of thousand years old. More discoveries are needed to match these time-scales with time since the decline of star formation in transitional galaxies. Such faint fuzzy relic emissions in optical and angular-scale sensitive radio interferometric images can be discov...

  2. Citizen Security

    OpenAIRE

    Beatriz Abizanda

    2011-01-01

    This is a presentation for the Caribbean Regional ConSoc Retreat held on June 16, 2011 in Kingston, Jamaica. This document outlines crime and violence as major roadblocks to development in the Caribbean; citing statistics and providing examples of the economic costs to the region. This presentation then goes on to describe the IDB's strategy with regard to citizen security and highlights IDB Funded security programs in the region. The presentation also identifies Civil Society as a potentiall...

  3. Broad-band radio circular polarization spectrum of the relativistic jet in PKS B2126-158

    Science.gov (United States)

    O'Sullivan, S. P.; McClure-Griffiths, N. M.; Feain, I. J.; Gaensler, B. M.; Sault, R. J.

    2013-10-01

    We present full Stokes radio polarization observations of the quasar PKS B2126-158 (z = 3.268) from 1 to 10 GHz using the Australia Telescope Compact Array. The source has large fractional circular polarization (CP), mc ≡ |V|/I, detected at high significance across the entire band (from 15 to 90σ per 128 MHz subband). This allows us to construct the most robust CP spectrum of an active galactic nucleus (AGN) jet to date. We find mc ∝ ν+0.60 ± 0.03 from 1.5 to 6.5 GHz, with a peak of mc ˜ 1 per cent before the spectrum turns over somewhere between 6.5 and 8 GHz, above which mc ∝ ν-3.0 ± 0.4. The fractional linear polarization (LP; p) varies from ≲0.2 to ˜1 per cent across our frequency range and is strongly anticorrelated with the fractional CP, with a best-fitting power law giving mc ∝ p-0.24 ± 0.03. This is the first clear relation between the observed LP and CP of an AGN jet, revealing the action of Faraday conversion of LP to CP within the jet. More detailed modelling in conjunction with high spatial resolution observations are required to determine the true driving force behind the conversion (i.e. magnetic twist or internal Faraday rotation). In particular determining whether the observed Faraday rotation is internal or entirely external to the jet is key to this goal. The simplest interpretation of our observations favours some internal Faraday rotation, implying that Faraday rotation-driven conversion of LP to CP is the dominant CP generation mechanism. In this case, a small amount of vector-ordered magnetic field along the jet axis is required, along with internal Faraday rotation from the low-energy end of the relativistic electron energy spectrum in an electron-proton-dominated jet.

  4. A New Approach to Suppress the Effect of Machining Error for Waveguide Septum Circular Polarizer at 230 GHz Band in Radio Astronomy

    Science.gov (United States)

    Hasegawa, Yutaka; Harada, Ryohei; Tokuda, Kazuki; Kimura, Kimihiro; Ogawa, Hideo; Onishi, Toshikazu; Nishimura, Atsushi; Han, Johnson; Inoue, Makoto

    2017-02-01

    A new stepped septum-type waveguide circular polarizer (SST-CP) was developed to operate in the 230 GHz band for radio astronomy, especially submillimeter-band VLBI observations. For previously reported SST-CP models, the 230 GHz band is too high to achieve the design characteristics in manufactured devices because of unexpected machining errors. To realize a functional SST-CP that can operate in the submillimeter band, a new method was developed, in which the division surface is shifted from the top step of the septum to the second step from the top, and we simulated the expected machining error. The SST-CP using this method can compensate for specified machining errors and suppress serious deterioration. To verify the proposed method, several test pieces were manufactured, and their characteristics were measured using a VNA. These results indicated that the insertion losses were approximately 0.75 dB, and the input return losses and the crosstalk of the left- and right-hand circular polarization were greater than 20 dB at 220-245 GHz on 300 K. Moreover, a 230 GHz SST-CP was developed by the proposed method and installed in a 1.85-m radio telescope receiver systems, and then had used for scientific observations during one observation season without any problems. These achievements demonstrate the successful development of a 230 GHz SST-CP for radio astronomical observations. Furthermore, the proposed method can be applicable for observations in higher frequency bands, such as 345 GHz.

  5. Deconvolution of images in centimeter-band radio astronomy for the exploitation of new radio interferometers: characterization of non thermal components in galaxy clusters

    Science.gov (United States)

    Dabbech, A.

    2015-04-01

    Within the framework of the preparation for the Square Kilometre Array (SKA), that is the world largest radio telescope, new imaging challenges has to be conquered. The data acquired by SKA will have to be processed on real time because of their huge rate. In addition, thanks to its unprecedented resolution and sensitivity, SKA images will have very high dynamic range over wide fields of view. Hence, there is an urgent need for the design of new imaging techniques that are robust and efficient and fully automated. The goal of this thesis is to develop a new technique aiming to reconstruct a model image of the radio sky from the radio observations. The method have been designed to estimate images with high dynamic range with a particular attention to recover faint extended emission usually completely buried in the PSF sidelobes of the brighter sources and the noise. We propose a new approach, based on sparse representations, called MORESANE. The radio sky is assumed to be a summation of sources, considered as atoms of an unknown synthesis dictionary. These atoms are learned using analysis priors from the observed image. Results obtained on realistic simulations show that MORESANE is very promising in the restoration of radio images; it is outperforming the standard tools and very competitive with the newly proposed methods in the literature. MORESANE is also applied on simulations of observations using the SKA1 with the aim to investigate the detectability of the intracluster non thermal component. Our results indicate that these diffuse sources, characterized by very low surface brightness will be investigated up to the epoch of massive cluster formation with the SKA.

  6. Coding for stable transmission of W-band radio-over-fiber system using direct-beating of two independent lasers.

    Science.gov (United States)

    Yang, L G; Sung, J Y; Chow, C W; Yeh, C H; Cheng, K T; Shi, J W; Pan, C L

    2014-10-20

    We demonstrate experimentally Manchester (MC) coding based W-band (75 - 110 GHz) radio-over-fiber (ROF) system to reduce the low-frequency-components (LFCs) signal distortion generated by two independent low-cost lasers using spectral shaping. Hence, a low-cost and higher performance W-band ROF system is achieved. In this system, direct-beating of two independent low-cost CW lasers without frequency tracking circuit (FTC) is used to generate the millimeter-wave. Approaches, such as delayed self-heterodyne interferometer and heterodyne beating are performed to characterize the optical-beating-interference sub-terahertz signal (OBIS). Furthermore, W-band ROF systems using MC coding and NRZ-OOK are compared and discussed.

  7. A New 100-GHz Band Two-Beam Sideband-Separating SIS Receiver for Z-Machine on the NRO 45-m Radio Telescope

    CERN Document Server

    Nakajima, Taku; Nishimura, Atsushi; Iwashita, Hiroyuki; Miyazawa, Chieko; Sakai, Takeshi; Iono, Daisuke; Kohno, Kotaro; Kawabe, Ryohei; Kuno, Nario; Ogawa, Hideo; Asayama, Shin'ichiro; Tamura, Tomonori; Noguchi, Takashi

    2013-01-01

    We have developed a two-beam waveguide-type dual-polarization sideband-separating SIS receiver system in the 100-GHz band for {\\it z}-machine on the 45-m radio telescope at the Nobeyama Radio Observatory. The receiver is intended for astronomical use in searching for highly redshifted spectral lines from galaxies of unknown redshift. This receiver has two beams, which have 45$^{\\prime\\prime}$ of beam separation and allow for observation with the switch in the on-on position. The receiver of each beam is composed of an ortho-mode transducer and two sideband-separating SIS mixers, which are both based on a waveguide technique, and the receiver has four intermediate frequency bands of 4.0--8.0 GHz. Over the radio frequency range of 80--116 GHz, the single-sideband receiver noise temperature is lower than about 50 K, and the image rejection ratios are greater than 10 dB in most of the same frequency range. The new receiver system has been installed in the telescope, and we successfully observed a $^{12}$CO ({\\it ...

  8. Miniaturized UHF, S-, and Ka-band RF MEMS Filters for Small Form Factor, High Performance EVA Radio Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In Phase II of this SBIR, Harmonic Devices (HDI) proposes to develop miniaturized MEMS filters at UHF, S-band and Ka-band to address the requirements of NASA's...

  9. On the origin of the ionosphere at Moon : a study using results from Chandrayaan-I S-band radio occultation experiment and a photochemical model

    Science.gov (United States)

    Kailasam Madathil, Ambili; Bhardwaj, Anil; Choudhary, Raj Kumar

    2016-07-01

    Using Chandrayaan-1 communication link between orbiter and ground (S-band frequency), the presence of ionosphere at Moon has been explored using Radio Occultation technique. Results obtained from the observations conducted between July 30 and August 14, 2009 show evidence for a possible existence of the Ionosphere at Moon. A few seconds before the occultation of Chandrayaan-1 radio signals, extra fluctuation in the rate of change of difference between the theoretically estimated Doppler and observed Doppler was observed. The fluctuation was more pronounced when the probing radio waves were crossing through the day-night terminator. Using standard onion-peeling technique to invert the phase changes in radio signals to the refractivity of the medium, we estimated the bending angle and hence the electron density profiles for the Lunar medium. The estimated electron density near the Lunar surface was of the order of 400 - 1000 cm ^{-3} which decreased monotonically with increasing altitude till about 40 km above the surface where it became negligible. The observed electron density was compared with the results from a model which was developed based on CHACE measurements abroad Moon Impact Probe of Chandrayaan-I. The model included the photo chemical reactions and solar wind interactions of the lunar plasma. We propose that the ionosphere over Moon could have molecular origin with H _{2}O ^{+},CO_{2} ^{+} and H_{3}O ^{+} as dominant ions.

  10. Extremely high cm-band radio flux level of the gamma-ray flaring FSRQ PKS 1510-089

    Science.gov (United States)

    Orienti, M.; D'Ammando, F.; Giroletti, M.; Orlati, A.

    2011-11-01

    The 32-m single dish antenna located at Medicina has been observing the flat spectrum radio quasar PKS 1510-089 starting from July 2011 with monthly frequency. The observations were organised as a follow-up of the gamma-ray flaring event reported in July 2011 by AGILE (ATel #3470) and Fermi (ATel #3473). Recently, radio observations were performed at 4.9 GHz and 8.0 GHz on 2011 November 16.

  11. The Extreme Gamma-Ray Blazar S5 0716+714: Jet Conditions from Radio-Band Variability and Radiative Transfer Modeling

    CERN Document Server

    Aller, M F; Aller, H D; Jorstad, S G; Marscher, A P; Bala, V; Hovatta, T

    2015-01-01

    As part of a program to identify the physical conditions in the jets of gamma-ray-flaring blazars detected by Fermi, including the role of shocks in the production of high-energy flaring, we obtained 4 years of 3-frequency, centimeter-band total flux density and linear polarization monitoring observations of the radio-bright blazar S5 0716+714 with the University of Michigan 26-m paraboloid. Light curves constructed from these data exhibit a series of rapid, high-amplitude, centimeter-band total flux density outbursts, and changes in the linear polarization consistent with the passage of shocks during the gamma-ray flaring. The observed spectral evolution of the radio-band flares, in combination with radiative transfer simulations incorporating propagating shocks, was used to constrain the shock and jet flow conditions in the parsec-scale regions of the jet. Eight forward-moving, transverse shocks with unusually-strong shock compression factors, a very fast Lorentz factor of the shocks of 77, a bulk Lorentz f...

  12. 40 Gb/s W-band (75-110 GHz) 16-QAM radio-over-fiber signal generation and its wireless transmission.

    Science.gov (United States)

    Kanno, Atsushi; Inagaki, Keizo; Morohashi, Isao; Sakamoto, Takahide; Kuri, Toshiaki; Hosako, Iwao; Kawanishi, Tetsuya; Yoshida, Yuki; Kitayama, Ken-ichi

    2011-12-12

    The generation of a 40-Gb/s 16-QAM radio-over-fiber (RoF) signal and its demodulation of the wireless signal transmitted over free space of 30 mm in W-band (75-110 GHz) is demonstrated. The 16-QAM signal is generated by a coherent polarization synthesis method using a dual-polarization QPSK modulator. A combination of the simple RoF generation and the versatile digital receiver technique is suitable for the proposed coherent optical/wireless seamless network.

  13. Evaluation of quadrature-phase-shift-keying signal characteristics in W-band radio-over-fiber transmission using direct in-phase/quadrature-phase conversion technique

    Science.gov (United States)

    Suzuki, Meisaku; Kanno, Atsushi; Yamamoto, Naokatsu; Sotobayashi, Hideyuki

    2016-02-01

    The effects of in-phase/quadrature-phase (IQ) imbalances are evaluated with a direct IQ down-converter in the W-band (75-110 GHz). The IQ imbalance of the converter is measured within a range of +/-10 degrees in an intermediate frequency of DC-26.5 GHz. 1-8-G-baud quadrature phase-shift keying (QPSK) signals are transmitted successfully with observed bit error rates within a forward error correction limit of 2×10-3 using radio over fiber (RoF) techniques. The direct down-conversion technique is applicable to next-generation high-speed wireless access communication systems in the millimeter-wave band.

  14. Radio Channel Sounding Using a Circular Horn Antenna Array in the Horizontal Plane in the 2.3 GHz Band

    DEFF Research Database (Denmark)

    Yamamoto, Atsushi; Sakata, Tsutomu; Ogawa, Koichi

    2012-01-01

    This paper presents results from an outdoor radio propagation experiment at 2.35 GHz using a channel sounder and a spherical horn antenna array. The propagation test was performed in Aalborg city in Denmark. Comparing the ray-tracing results and the results obtained with the proposed method...

  15. Multi-band radio over fiber system with all-optical halfwave rectification, transmission and frequency down-conversion

    DEFF Research Database (Denmark)

    Prince, Kamau; Tafur Monroy, Idelfonso

    2011-01-01

    We introduce a novel application of all-optical half-wave rectification in the transportation and delivery of multi-frequency radio-over fiber signals. System evaluation was performed of transmission over various optical fiber types and all-optical envelope detection was implemented to achieve...

  16. Wide-field broad-band radio imaging with phased array feeds: a pilot multi-epoch continuum survey with ASKAP-BETA

    Science.gov (United States)

    Heywood, I.; Bannister, K. W.; Marvil, J.; Allison, J. R.; Ball, L.; Bell, M. E.; Bock, D. C.-J.; Brothers, M.; Bunton, J. D.; Chippendale, A. P.; Cooray, F.; Cornwell, T. J.; De Boer, D.; Edwards, P.; Gough, R.; Gupta, N.; Harvey-Smith, L.; Hay, S.; Hotan, A. W.; Indermuehle, B.; Jacka, C.; Jackson, C. A.; Johnston, S.; Kimball, A. E.; Koribalski, B. S.; Lenc, E.; Macleod, A.; McClure-Griffiths, N.; McConnell, D.; Mirtschin, P.; Murphy, T.; Neuhold, S.; Norris, R. P.; Pearce, S.; Popping, A.; Qiao, R. Y.; Reynolds, J. E.; Sadler, E. M.; Sault, R. J.; Schinckel, A. E. T.; Serra, P.; Shimwell, T. W.; Stevens, J.; Tuthill, J.; Tzioumis, A.; Voronkov, M. A.; Westmeier, T.; Whiting, M. T.

    2016-04-01

    The Boolardy Engineering Test Array is a 6 × 12 m dish interferometer and the prototype of the Australian Square Kilometre Array Pathfinder (ASKAP), equipped with the first generation of ASKAP's phased array feed (PAF) receivers. These facilitate rapid wide-area imaging via the deployment of simultaneous multiple beams within an ˜30 deg2 field of view. By cycling the array through 12 interleaved pointing positions and using nine digitally formed beams, we effectively mimic a traditional 1 h × 108 pointing survey, covering ˜150 deg2 over 711-1015 MHz in 12 h of observing time. Three such observations were executed over the course of a week. We verify the full bandwidth continuum imaging performance and stability of the system via self-consistency checks and comparisons to existing radio data. The combined three epoch image has arcminute resolution and a 1σ thermal noise level of 375 μJy beam-1, although the effective noise is a factor of ˜3 higher due to residual sidelobe confusion. From this we derive a catalogue of 3722 discrete radio components, using the 35 per cent fractional bandwidth to measure in-band spectral indices for 1037 of them. A search for transient events reveals one significantly variable source within the survey area. The survey covers approximately two-thirds of the Spitzer South Pole Telescope Deep Field. This pilot project demonstrates the viability and potential of using PAFs to rapidly and accurately survey the sky at radio wavelengths.

  17. High Efficiency Traveling-Wave Tube Power Amplifier for Ka-Band Software Defined Radio on International Space Station-A Platform for Communications Technology Development

    Science.gov (United States)

    Simons, Rainee N.; Force, Dale A.; Kacpura, Thomas J.

    2013-01-01

    The design, fabrication and RF performance of the output traveling-wave tube amplifier (TWTA) for a space based Ka-band software defined radio (SDR) is presented. The TWTA, the SDR and the supporting avionics are integrated to forms a testbed, which is currently located on an exterior truss of the International Space Station (ISS). The SDR in the testbed communicates at Ka-band frequencies through a high-gain antenna directed to NASA s Tracking and Data Relay Satellite System (TDRSS), which communicates to the ground station located at White Sands Complex. The application of the testbed is for demonstrating new waveforms and software designed to enhance data delivery from scientific spacecraft and, the waveforms and software can be upgraded and reconfigured from the ground. The construction and the salient features of the Ka-band SDR are discussed. The testbed is currently undergoing on-orbit checkout and commissioning and is expected to operate for 3 to 5 years in space.

  18. Adaptive linear predictor FIR filter based on the Cyclone V FPGA with HPS to reduce narrow band RFI in AERA radio detection of cosmic rays

    Energy Technology Data Exchange (ETDEWEB)

    Szadkowski, Zbigniew [University of Lodz, Department of Physics and Applied Informatics, 90-236 Lodz, (Poland)

    2015-07-01

    We present the new approach to a filtering of radio frequency interferences (RFI) in the Auger Engineering Radio Array (AERA) which study the electromagnetic part of the Extensive Air Showers. The radio stations can observe radio signals caused by coherent emissions due to geomagnetic radiation and charge excess processes. AERA observes frequency band from 30 to 80 MHz. This range is highly contaminated by human-made RFI. In order to improve the signal to noise ratio RFI filters are used in AERA to suppress this contamination. The first kind of filter used by AERA was the Median one, based on the Fast Fourier Transform (FFT) technique. The second one, which is currently in use, is the infinite impulse response (IIR) notch filter. The proposed new filter is a finite impulse response (FIR) filter based on a linear prediction (LP). A periodic contamination hidden in a registered signal (digitized in the ADC) can be extracted and next subtracted to make signal cleaner. The FIR filter requires a calculation of n=32, 64 or even 128 coefficients (dependent on a required speed or accuracy) by solving of n linear equations with coefficients built from the covariance Toeplitz matrix. This matrix can be solved by the Levinson recursion, which is much faster than the Gauss procedure. The filter has been already tested in the real AERA radio stations on Argentinean pampas with a very successful results. The linear equations were solved either in the virtual soft-core NIOSR processor (implemented in the FPGA chip as a net of logic elements) or in the external Voipac PXA270M ARM processor. The NIOS processor is relatively slow (50 MHz internal clock), calculations performed in an external processor consume a significant amount of time for data exchange between the FPGA and the processor. Test showed a very good efficiency of the RFI suppression for stationary (long-term) contaminations. However, we observed a short-time contaminations, which could not be suppressed either by the

  19. Relation between the "Double-Hump" Behavior in the Radio Band and the Broad-Line Luminosity for Blazars

    Institute of Scientific and Technical Information of China (English)

    Zhao-Hua Xie; Hong Dai; Jian-Ming Hao; Lei-Ming Du; Xiong Zhang

    2007-01-01

    The physics behind the spectral energy distribution (SED) of blazars remains open.We assembled 36 blazars to tackle the factors that control their SED. Now, many blazar spectra have the "double hump" feature in the radio and far-IR frequencies. For these a parameter,△, is created to characterize the behavior of the SED. We found a significant correlation between the broad-line luminosity (LBLR) and △. Because LBLR is an indicator of the accreting power of the source in blazars, we derived a linear correlation,△∝ (M)1/3. 18, which suggests that the SED of blazars may depend on the accretion rate, like that of BL Lac objects. We also found a significant correlation between (m) and△ for a sample of 11 blazars (out of one of 36)with available black hole masses. This implies the Eddington accretion ratio may influence the shape of the SED of blazars.

  20. W-band OFDM Radio-over-Fiber system with power detector for vector signal down-conversion.

    Science.gov (United States)

    Lin, Chun-Ting; Wu, Meng-Fan; Ho, Chun-Hung; Li, Che-Hao; Lin, Chi-Hsiang; Huang, Hou-Tzu

    2015-06-01

    This Letter proposes a W-band OFDM RoF system at 103.5 GHz employing power detector to support vector signal down-conversion. Additional RF tone is generated and transmitted from central office to replace the local oscillator at a wireless receiver. With a proper frequency gap and power ratio between the RF tone and the OFDM-modulated signal, the impact from signal-to-signal beating interference can be minimized. The data rate can achieve a 40 Gbps 16 QAM OFDM signal over 25 km fiber and 2 m wireless transmission.

  1. Rapid and correlated variability of blazar S5 0716+71 from radio- to sub-mm bands

    CERN Document Server

    Fuhrmann, L; Witzel, A; Agudo, I; Britzen, S; Bernhart, S; Impellizzeri, V; Kraus, A L; Angelakis, E; Bach, U; Gabanyi, K E; Zensus, J A

    2006-01-01

    The BL Lac object S5 0716+71 was target of a coordinated and global multi-frequency campaign to search for rapid and correlated variability and signatures of the inverse-Compton catastrophe. Here we present first results obtained from a combined analysis of the cm- to sub-mm observations over a period of seven days aiming at a detailed study of the intra- to inter-day variability characteristics and to obtain constraints on the variability brightness temperatures and Doppler factors comparing the radio data with the high energy emission recorded by INTEGRAL. A more detailed description of the whole cm- to sub-mm observations and our analysis/results will be presented in a forthcoming paper. Our analysis reveals the source to be in a particular short-term variability phase when compared to the past with a correlated >~4 day time scale amplitude increase of up to 35%, which is systematically more pronounced towards higher frequencies. The obtained frequency dependent variability amplitudes and time lags contrad...

  2. Two-layer radio frequency MEMS fractal capacitors in PolyMUMPS for S-band applications

    KAUST Repository

    Elshurafa, Amro M.

    2012-07-23

    In this Letter, the authors fabricate for the first time MEMS fractal capacitors possessing two layers and compare their performance characteristics with the conventional parallel-plate capacitor and previously reported state-of-the-art single-layer MEMS fractal capacitors. Explicitly, a capacitor with a woven structure and another with an interleaved configuration were fabricated in the standard PolyMUMPS surface micromachining process and tested at S-band frequencies. The self-resonant frequencies of the fabricated capacitors were close to 10GHz, which is better than that of the parallel-plate capacitor, which measured only 5.5GHz. Further, the presented capacitors provided a higher capacitance when compared with the state-of-the-art-reported MEMS fractal capacitors created using a single layer at the expense of a lower quality factor. © 2012 The Institution of Engineering and Technology.

  3. Effects of electron beam parameters and velocity spread on radio frequency output of a photonic band gap cavity gyrotron oscillator

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Ashutosh, E-mail: asingh.rs.ece@iitbhu.ac.in [Faculty of Physical Sciences, Institute of Natural Sciences and Humanities, Shri Ramswaroop Memorial University, Lucknow-Deva Road, Uttar Pradesh 225003 (India); Center of Research in Microwave Tubes, Department of Electronics Engineering, Indian Institute of Technology (Banaras Hindu University), Varanasi 221005 (India); Jain, P. K. [Center of Research in Microwave Tubes, Department of Electronics Engineering, Indian Institute of Technology (Banaras Hindu University), Varanasi 221005 (India)

    2015-09-15

    In this paper, the effects of electron beam parameters and velocity spread on the RF behavior of a metallic photonic band gap (PBG) cavity gyrotron operating at 35 GHz with TE{sub 041}–like mode have been theoretically demonstrated. PBG cavity is used here to achieve a single mode operation of the overmoded cavity. The nonlinear time-dependent multimode analysis has been used to observe the beam-wave interaction behavior of the PBG cavity gyrotron, and a commercially available PIC code “CST Particle Studio” has been reconfigured to obtain 3D simulation results in order to validate the analytical values. The output power for this typical PBG gyrotron has been obtained ∼108 kW with ∼15.5% efficiency in a well confined TE{sub 041}–like mode, while all other competing modes have significantly low values of power output. The output power and efficiency of a gyrotron depend highly on the electron beam parameters and velocity spread. The influence of several electron beam parameters, e.g., beam voltage, beam current, beam velocity pitch factor, and DC magnetic field, on the PBG gyrotron operations has been investigated. This study would be helpful in optimising the electron beam parameters and estimating accurate RF output power of the high frequency PBG cavity based gyrotron oscillators.

  4. Studies on charge production from Cs2Te photocathodes in the PITZ L-band normal conducting radio frequency photo injector

    CERN Document Server

    Hernandez-Garcia, C; Asova, G; Bakr, M; Boonpornprasert, P; Good, J; Gross, M; Huck, H; Isaev, I; Kalantaryan, D; Khojoyan, M; Kourkafas, G; Lishilin, O; Malyutin, D; Melkumyan, D; Oppelt, A; Otevrel, M; Pathak, G; Renier, Y; Rublack, T; Stephan, F; Vashchenko, G; Zhao, Q

    2016-01-01

    This paper discusses the behavior of electron bunch charge produced in an L-band normal conducting radio frequency cavity (RF gun) from Cs2Te photocathodes illuminated with ps-long UV laser pulses when the laser transverse distribution consists of a flat-top core with Gaussian-like decaying halo. The produced charge shows a linear dependence at low laser pulse energies as expected in the quantum efficiency limited emission regime, while its dependence on laser pulse energy is observed to be much weaker for higher values, due to space charge limited emission. However, direct plug-in of experimental parameters into the space charge tracking code ASTRA yields lower output charge in the space charge limited regime compared to measured values. The rate of increase of the produced charge at high laser pulse energies close to the space charge limited emission regime seems to be proportional to the amount of halo present in the radial laser profile since the charge from the core has saturated already. By utilizing co...

  5. Topology optimization of patch-typed left-handed metamaterial configurations for transmission performance within the radio frequency band based on the genetic algorithm

    Science.gov (United States)

    Dong, Yanzhang; Liu, Shutian

    2012-10-01

    For the requirement of broadband transmission with low attenuation within the radio frequency band, a topology optimization model of microstructure configuration design of patch-typed left-handed metamaterials is established, with the objective function defined by the ratio of the mean attenuation to the absolute left-handed bandwidth; then a genetic algorithm based solution method and flow chart of the topology optimization are presented. An improved electromagnetic simulation analysis method is used to obtain accurate equivalent electromagnetic parameters from the S-parameter retrieval process. Three patch-typed microstructure configurations are given according to the results of topology optimization designs for different lattice sizes, and the transmission performance indicators of these creative configurations are computed and analyzed by numerical simulation. The contrast of the design results shows that a U-shaped-like structure of half a unit cell height exists among all these optimum configurations. It is found through a further analysis that the distribution of conduction currents of U-shaped-like structures is the key to broadband transmission with low attenuation. Finally, a new topology optimization design with the perimeter constraint is proposed to solve the problem in the manufacturing process for checkerboard-typed lattices from these configurations.

  6. Radiative Transfer Modeling of Radio-band Linear Polarization Observations as a Probe of the Physical Conditions in the Jets of Gamma-ray Flaring Blazars

    CERN Document Server

    Aller, Margo F; Aller, Hugh D; Hovatta, Talvikki; Ramakrishnan, Venkatessh

    2016-01-01

    Since the mid-1980s the shock-in-jet model has been the preferred paradigm to explain radio-band flaring in blazar jets. We describe our radiative transfer model incorporating relativistically-propagating shocks, and illustrate how the 4.8, 8, and 14.5 GHz linear polarization and total flux density data from the University of Michigan monitoring program, in combination with the model, constrain jet flow conditions and shock attributes. Results from strong Fermi-era flares in 4 blazars with widely-ranging properties are presented. Additionally, to investigate jet evolution on decadal time scales we analyze 3 outbursts in OT 081 spanning nearly 3 decades and find intrinsic changes attributable to flow changes at a common spatial location, or, alternatively, to a change in the jet segment viewed. The model's success in reproducing these data supports a scenario in which relativistic shocks compress a plasma with an embedded passive, initially-turbulent magnetic field, with additional ordered magnetic field compo...

  7. Aplikasi Citizen Journalism di Era Konvergensi Media

    Directory of Open Access Journals (Sweden)

    Rahmat Edi Irawan

    2014-10-01

    Full Text Available Citizen journalist has now become one of the concepts most developed television programs. If initially the concept is more widely used in radio and online media, this time with technology coverage and delivery of images that are easier and cheaper, it is a concept that provides a place for people to become amateur journalists also can be applied with ease in the medium of television. Application of citizen journalism in the television media is also increasingly facilitated by the start of the television is now the era of media convergence, different recent media, such as television media with print media , radio and internet media . The era of media convergence, making the concept of citizen journalism can be more developed , because of the platform or distribution media is also increasingly diverse television for the amateur journalists . However, the system equipment must be provided, human resources must be owned , as well as huge capital to be owned, make not many television stations that opened a lot of platforms to provide space for amateur journalists in citizen journalism

  8. Citizens Advisory Committees.

    Science.gov (United States)

    Stemnock, Suzanne K.

    1968-01-01

    This document contains the results of a national survey designed to determine the composition and location of permanent citizens advisory committees operating within the nation's school districts. The 52 district-wide, continuing citizens advisory bodies identified by 290 responding school systems are listed alphabetically by State. The following…

  9. Development of a Smooth Taper Double-Ridge Waveguide Orthomode Transducer for a New 100 GHz Band Z-Machine Receiver for the NRO 45-m Radio Telescope

    Science.gov (United States)

    Asayama, Shin’ichiro; Nakajima, Taku

    2013-02-01

    A smooth taper double-ridge waveguide orthomode transducer (OMT) has been designed for the new 100 GHz band receiver system on the Nobeyama Radio Observatory (NRO) 45-m radio telescope. The OMT consists of a smooth taper double-ridge waveguide followed by a Bøifot type junction with a main arm and two side arms. The main arm output is a smoothed tapered transformer followed by an E-plane bend and an oval waveguide. This design facilitates the fabrication of the OMT using split blocks machined on a CNC (computer numerical control) machine. The OMT shows a return loss of better than 18 dB, a polarization isolation of better than 28 dB, and an insertion loss of less than 0.5 dB across the 74–116 GHz, and also demonstrated the excellent performance on the NRO 45-m radio telescope.

  10. Civic learning and action among older citizens

    Science.gov (United States)

    Boggs, David L.

    1992-07-01

    The purposes of this article are first, to consider the role of senior citizens as advocates, both in matters of specific concern to their fellow age cohorts and in issues of general interest to the community; and, second, to examine the relationship of self-education and learning to advocacy in civic affairs. Literature on sociological and political theory as well as adult civic education provides a conceptual base from which to explain the involvement of persons in their later years in advocacy efforts and in learning activities designed to enhance civic involvement. Citizens have banded together to advocate their vision of a desired future throughout history. Citizen participation in political and civic affairs is generally age-integrated and intergenerational, thus affording opportunities to dispel negative age stereotypes. Participation in civic affairs invokes ageless values, creates meaning in life, and allows elderly participants to transcend themselves and their limitations.

  11. FPGA/NIOS Implementation of an Adaptive FIR Filter Using Linear Prediction to Reduce Narrow-Band RFI for Radio Detection of Cosmic Rays

    NARCIS (Netherlands)

    Szadkowski, Zbigniew; Fraenkel, E. D.; van den Berg, Ad M.

    2013-01-01

    We present the FPGA/NIOS implementation of an adaptive finite impulse response (FIR) filter based on linear prediction to suppress radio frequency interference (RFI). This technique will be used for experiments that observe coherent radio emission from extensive air showers induced by ultra-high-ene

  12. The coexistence of cognitive radio and radio astronomy

    NARCIS (Netherlands)

    Bentum, M.J.; Boonstra, A.J.; Baan, W.A.

    2009-01-01

    An increase of the efficiency of spectrum usage requires the development of new communication techniques. Cognitive radio may be one of those new technique, which uses unoccupied frequency bands for communications. This will lead to more power in the bands and therefore an increasing level of Radio

  13. Dust tori in radio galaxies

    NARCIS (Netherlands)

    van der Wolk, G.; Barthel, P. D.; Peletier, R. F.; Pel, J. W.

    2010-01-01

    Aims: We investigate the quasar - radio galaxy unification scenario and detect dust tori within radio galaxies of various types. Methods: Using VISIR on the VLT, we acquired sub-arcsecond (~0.40 arcsec) resolution N-band images, at a wavelength of 11.85 μm, of the nuclei of a sample of 27 radio gala

  14. A New 100-GHz Band Front-End System with a Waveguide-Type Dual-Polarization Sideband-Separating SIS Receiver for the NRO 45-m Radio Telescope

    CERN Document Server

    Nakajima, Taku; Kimura, Kimihiro; Yonekura, Yoshinori; Ogawa, Hideo; Sakai, Takeshi; Kuno, Nario; Tsuboi, Masato; Asayama, Shin'ichiro; Noguchi, Takashi; Kawabe, Ryohei

    2008-01-01

    We developed a waveguide-type dual-polarization sideband-separating SIS receiver system of the 100-GHz band for the 45-m radio telescope at the Nobeyama Radio Observatory, Japan. This receiver is composed of an ortho-mode transducer and two sideband-separating SIS mixers, which are both based on the waveguide technique. The receiver has four intermediate frequency bands of 4.0--8.0 GHz. Over the radio frequency range of 80--120 GHz, the single-sideband receiver noise temperatures are 50--100 K and the image rejection ratios are greater than 10 dB. We developed new matching optics for the telescope beam as well as new IF chains for the four IF signals. The new receiver system was installed in the telescope, and we successfully observed the 12CO, 13CO and C18O emission lines simultaneously toward the Sagittarius B2 region to confirm the performance of the receiver system. The SSB noise temperature of the system, including the atmosphere, became approximately half of that of the previous receiver system. The Ima...

  15. Who are the active citizens?

    DEFF Research Database (Denmark)

    Agger, Annika

    This article presents the variety of different active citizens and participants involved in a collaborative and participatory planning process within an urban regeneration project in Denmark. In much of the literature on planning and citizen participation citizens are often regarded as a homogenous...... group. This article argues that there are no `ordinary´ citizens, and claims that citizens are very different and participate in various ways. A criticism raised in relation to participatory processes is that these often tend to favour certain modes of communication based on an implicit ideal...... of the citizen as being resourceful, mastering political skills and know-how and time. However, many citizens do not `fit´ this stereotype, and thus there is a risk that many citizens are biased by the way the institutional settings for participation are designed. A characterization of active citizens...

  16. Perencanaan dan analisis kehandalan sistem komunikasi radio microwave tampak pandang pada pita frekuensi 12750-13250 MHz [Planning and analysis of the reliability of line of sight microwave radio communication system on 12750-13250 MHz band

    Directory of Open Access Journals (Sweden)

    Ahmad Hasyim

    2016-12-01

    Full Text Available Propagasi gelombang radio dapat diartikan sebagai proses perambatan gelombang radio dari pemancar ke penerima. Gelombang ini akan merambat melalui udara bebas menuju antena penerima dan mengalami redaman di sepanjang lintansannya,  redaman perangkat dan saluran transmisi, sehingga ketika sampai di antena penerima, energi sinyal sudah sangat lemah. Line of sight    (LOS merupakan salah satu jenis propagasi di mana diantara stasiun pengirim dan stasiun penerima  tidak terdapat penghalang. Kendala geografis dan kelengkungan bumi menyebabkan adanya keterbatasan untuk transmisi line of sight, namun masalah ini secara umum dapat dikurangi melalui perencanaan, perhitungan dan penggunaan teknologi tambahan. Dalam perencanaan sistem komunikasi radio, kinerja LOS perlu direncanakan cadangan daya akibat fluktuasi sinyal serta analisis kehandalannya. Sistem radio gelombang mikro digital antar titik yang menggunakan  frekuensi 13 GHz dengan modulasi 16 QAM, bit rate 140 MBps,dan  noise figure 0,7 dB memerlukan daya pancar -4,488 dBm, fading margin sebesar 85,51 dB dan kehandalannya sebesar 99,9999999%.*****Radio wave propagation can be defined as the process of propagation of radio waves from the transmitter to the receiver. These waves will propagate through free air towards the receiver antena with experienced curbs along the tracks, so when it arrive at the receiver antena, the signal energy is very slow. Line of sight (LOS is one kind of propagation where no obstacles found between the transmitter and the receiver station. Geographical constraints and the curvature of the earth bring limitations to the line of sight transmission, but this problem can generally be reduced through planning, calculation and use of additional technologies. In a radio communication system planning, LOS performance needs to be planned caused by signal fluctuations and reliability. Digital microwave point to point radio systems using 13 GHz of spectrum, 16 QAM of

  17. Effectiveness of citizen involvement

    Energy Technology Data Exchange (ETDEWEB)

    Robinson, L. [Prince William Sound Regional Citizen' s Advisory Council, Anchorage, AK (United States)

    2006-07-01

    This paper reviewed the rise of citizen involvement in industry that affects their community. Following the Exxon Valdez oil spill (EVOS) in 1989, the Oil Pollution Act of 1990 provided funding by industry for a citizens group to provide oversite of the Alyeska Pipeline Service Agency terminal and associated tankers. That role is currently filled by the Prince William Sound Regional Citizen's Advisory Council, a volunteer organization that represents communities that were affected by the EVOS. The history of the Prince William Sound Regional Citizen's Advisory Council was discussed along with its structure, funding and overview of projects and research into safer transportation of oil, better oil spill response capabilities and improved environmental protection practices. Some of the successes involving citizen input include the requirement that all tankers going into Prince William Sound be double hull by 2015; a world-class system of tugs escorting tankers in Prince William Sound; installation of an ice-detection radar on a small island near the site of the EVOS; a guidebook for communities affected by man-made disasters; identification of nearshore locations that should be the first to be protected in the case of another spill; and, the installation of a system to capture crude oil vapors when tankers take on cargo. Other projects underway include the study of invasive species that can be transported in the ballast water of tankers, efficacy of dispersants, soil contamination at the tanker loading site, emissions of hazardous air pollutants from ballast water treatment processes, and continual review of emergency response plans. In the 17 years since the formation of the Prince William Sound Regional Citizen's Advisory Council, it has been shown that communication and transparency are the keys to solving complacency, which is believed to have been a contributing factor to the EVOS. 3 refs.

  18. Citizens4Citizens: mapping participatory practices on the internet

    NARCIS (Netherlands)

    Meijer, Albert; Burger, Nils; Ebbers, Wolfgang

    2009-01-01

    Many important forms of public participation take place in interactions between citizens. Studying these interactions is crucial for understanding e‑governance, defined as steering in the public domain. The new forms of public participations can be labeled Citizens2Citizens interactions (C2C). Citiz

  19. Bidirectional 3.125 Gbps downstream / 2 Gbps upstream impulse radio ultrawide-band (UWB) over combined fiber and wireless link

    DEFF Research Database (Denmark)

    Jensen, Jesper Bevensee; Gibbon, Timothy Braidwood; Yu, Xianbin;

    2010-01-01

    We demonstrate bidirectional fiber and wireless transmission of impulse radio ultra-wideband at 3.125 Gbps downstream and 2 Gbps upstream. After transmission over 50 km fiber and 1.85 m wireless link both signals are recovered without errors.......We demonstrate bidirectional fiber and wireless transmission of impulse radio ultra-wideband at 3.125 Gbps downstream and 2 Gbps upstream. After transmission over 50 km fiber and 1.85 m wireless link both signals are recovered without errors....

  20. Masked or Informed Citizens?

    DEFF Research Database (Denmark)

    Andersen, Kim Normann; Medaglia, Rony

    2012-01-01

    The diffusion of social media is having profound impacts on the relationship between government and citizens in many areas of government service provision. In the area of healthcare the emergence of new venues of interaction between patients and between patients and doctors is challenging....... In the conclusion, we suggest venues of future research on this emerging trend....

  1. Citizens in fear?

    NARCIS (Netherlands)

    Janneke Oppelaar; Karin Wittebrood

    2006-01-01

    Original title: Angstige burgers How afraid are citizens of crime, and has that fear increased or decreased in recent years? Which factors make people feel unsafe and how susceptible are they to influence? This publication looks extensively at these questions. As well as an overview of the scientif

  2. Educating Digital Citizens

    Science.gov (United States)

    Tan, Thomas

    2011-01-01

    Digital citizenship is how educators, citizens, and parents can teach where the lines of cyber safety and ethics are in the interconnected online world their students will inhabit. Aside from keeping technology users safe, digital citizenship also prepares students to survive and thrive in an environment embedded with information, communication,…

  3. Broad-band modelling of short gamma-ray bursts with energy injection from magnetar spin-down and its implications for radio detectability

    NARCIS (Netherlands)

    B.P. Gompertz; A.J. van der Horst; P.T. O'Brien; G.A. Wynn; K. Wiersema

    2015-01-01

    The magnetar model has been proposed to explain the apparent energy injection in the X-ray light curves of short gamma-ray bursts (SGRBs), but its implications across the full broad-band spectrum are not well explored. We investigate the broad-band modelling of four SGRBs with evidence for energy in

  4. Citizen participation in public accountability

    DEFF Research Database (Denmark)

    Damgaard, Bodil; Lewis, Jenny

    2014-01-01

    In this chapter we offer an analytical framework sensitive to the quality of citizen participation, which is measured in terms of transferred power from the governors to the citizens, and in terms of the degree to which citizens have access to accountability measures. We do this by combining...... Arnstein’s (1969) classic ladder of participation with a focus on citizen participation in regard to bureaucratic accountability, centered on efficiency and learning (cf. Bovens et al. 2008)....

  5. Citizen Involvement in Public Television.

    Science.gov (United States)

    Wenner, Lawrence A.

    The purpose of this study was to evaluate the amount and quality of citizen involvement in public television. From the perspective of the "average citizen," the concept of involvement is considered with regard to the Carnegie Commission, the Corporation for Public Broadcasting (CPB) borad of directors, the National Citizens Committee for…

  6. Colleges and Universities as Citizens.

    Science.gov (United States)

    Bringle, Robert G., Ed.; Games, Richard, Ed.; Malloy, Edward A., Ed.

    This collection of 10 essays focuses on the role of colleges and universities as engaged citizens seeking to better their communities. The essays include: (1) "Colleges and Universities as Citizens: Issues and Perspectives" (Robert G. Bringle, Richard Games, and Edward A. Malloy); (2) "Ernest L. Boyer: Colleges and Universities as Citizens"…

  7. Testing the inverse-Compton catastrophe scenario in the intra-day variable blazar S5 0716+71, III. Rapid and correlated flux density variability from radio to sub-mm bands

    CERN Document Server

    Fuhrmann, L; Witzel, A; Kraus, A; Britzen, S; Bernhart, S; Impellizzeri, C M V; Agudo, I; Klare, J; Sohn, B W; Angelakis, E; Bach, U; Gab'anyi, K 'E; K"ording, E; Pagels, A; Zensus, J A; Wagner, S J; Ostorero, L; Ungerechts, H; Grewing, M; Tornikoski, M; Apponi, A J; Vila-Vilar'o, B; Ziurys, L M; Strom, R G

    2008-01-01

    The BL Lac object S5 0716+71 was observed in a global multi-frequency campaign to search for rapid and correlated flux density variability and signatures of an inverse-Compton (IC) catastrophe during the states of extreme apparent brightness temperatures. The observing campaign involved simultaneous monitoring at radio to IR/optical wavelengths centered around a 500-ks INTEGRAL pointing (November 10-17, 2003). We present the combined analysis and results of the cm- to sub-mm observations including a detailed study of the inter- to intra-day variability and spectral characteristics of 0716+714. We further constrain the variability brightness temperatures (T_B) and Doppler factors (delta) comparing the radio-bands with the hard X-ray emission (3-200 keV). 0716+714 was in an exceptionally high state (outburst) and different (slower) phase of short-term variability. The flux density variability in the cm- to mm-bands is dominated by a correlated, ~4 day time scale amplitude increase of up to ~35% systematically m...

  8. Citizen Goals Online

    Directory of Open Access Journals (Sweden)

    Catalin Vrabie

    2012-07-01

    Full Text Available The purpose of this paper is to give to public institution Web designers a better understanding of the citizens’ objectives when accessing a Web page. Understanding citizen online goals is critical because it gets to the heart of what the public institution website should or could “do.”Approach: The challenge for e-marketers is that for most agencies/institutions, there are likely to be multiple goals that represent the “reason why” citizens could come to the website. For example, a national theatre website might be very effective for people who have already been there, they know effectively what place is the best, who are the actors, etc.Research limitations: The nature of a public institution activity almost dictates the different types of goals that consumers have when visiting the site. It is clear that a citizen has a different goal when accessing a theatre Web page or when he’s accessing a municipality Web page. This is the biggest impediment for drawing a good conceptual model for a public institution Web page.Practical implications: there are likely to be many other goals that could lead people to visit the site, like receiving customer service or leaving a remark.Value: Since citizen online goals represent the starting point for Web design efforts (for public institutions, this article has attempted to highlight the nature and types of goals that e-marketers might consider when planning what their website should do in order to create.Findings: The goal a site visitor has when arriving at a website tends to be very action oriented. If the visitor has never visited the site before, the goal may simply be to evaluate the website and figure out what the site is and if it will help him. On the other hand, if the visitor has reached the site as the result of a directed search or is a repeat visitor, the user goal is likely to be specific and functional. If important citizen goals are not supported by the website, the public

  9. Citizen Goals Online

    Directory of Open Access Journals (Sweden)

    Catalin Vrabie

    2013-01-01

    Full Text Available The purpose of this paper is to give to public institution Web designers a better understanding of the citizens’ objectives when accessing a Web page. Understanding citizen online goals is critical because it gets to the heart of what the public institution website should or could “do.” Approach: The challenge for e-marketers is that for most agencies/institutions, there are likely to be multiple goals that represent the “reason why” citizens could come to the website. For example, a national theatre website might be very effective for people who have already been there, they know effectively what place is the best, who are the actors, etc. Research limitations: The nature of a public institution activity almost dictates the different types of goals that consumers have when visiting the site. It is clear that a citizen has a different goal when accessing a theatre Web page or when he’s accessing a municipality Web page. This is the biggest impediment for drawing a good conceptual model for a public institution Web page. Practical implications: there are likely to be many other goals that could lead people to visit the site, like receiving customer service or leaving a remark. Value: Since citizen online goals represent the starting point for Web design efforts (for public institutions, this article has attempted to highlight the nature and types of goals that e-marketers might consider when planning what their website should do in order to create. Findings: The goal a site visitor has when arriving at a website tends to be very action oriented. If the visitor has never visited the site before, the goal may simply be to evaluate the website and figure out what the site is and if it will help him. On the other hand, if the visitor has reached the site as the result of a directed search or is a repeat visitor, the user goal is likely to be specific and functional. If important citizen goals are not supported by the website, the public

  10. Synergy Between Radio and Optical Telescopes: Optical Followup of Extragalactic Radio Sources

    Indian Academy of Sciences (India)

    C. H. Ishwara-Chandra

    2013-06-01

    Distance measurement is a must to characterize any source in the sky. In the radio band, it is rarely possible to get distance or redshift measurements. The optical band is the most used band to get distance estimate of sources, even for those originally discovered in other bands of the electromagnetic spectrum. However, the spectroscopic redshift measurements even for fairly bright radio sample is grossly incomplete, implying un-explored discovery space. Here we discuss the scope of optical follow up of radio sources, in particular the radio loud AGNs, from the present generation radio telescopes.

  11. Citizen(s') Science. A Response to "The Future of Citizen Science"

    Science.gov (United States)

    Calabrese Barton, Angela M.

    2012-01-01

    Citizen science is fundamentally about participation within and for communities. Attempts to merge citizen science with schooling must call not only for a democratization of schooling and science but also for the democratization of the ways in which science is taken up by, with, and for citizen participants. Using this stance, along with critical…

  12. Citizens in sustainable transitions

    DEFF Research Database (Denmark)

    Hoffmann, Birgitte; Agger, Annika

    2013-01-01

    The paper explores how local public authorities can support and facilitate citizens’ participa-tion and learning in sustainable transition in urban neighbourhoods, by supporting local in-termediaries. The role of intermediaries can be performed by a variety of actors such as public housing...... associations; NGO´s, or semi public institutions. Our claim is that intermediary actors have the potential to facilitate new platforms for citizens’ participation in urban sustainable transition due to their particular role in between public authorities and civil society. The key question of the paper is how...... the intermediary actors facilitate citizens' participatory processes in sustainable urban transitions, and the paper explores the concept of institutional capacity building as a way to develop learning processes and new practises? The aim is to analyse approaches of creating platforms for involving citizens...

  13. Governability and Citizen Participation

    Directory of Open Access Journals (Sweden)

    Giancarla de Quiroga

    1999-10-01

    Full Text Available bjective conditions that allow for a harmonic relationship between the governors and the governed. We are speaking about a set of conditions for governing by consensus and in harmony. By “citizen participation” we refer to the fact that citizens share in the powerof decision over something that concerns them. In Bolivia, as well in other Latin American countries, citizenship participation in municipal management is a recent phenomena. This article describes the experience of citizenry participation in the municipality ofCochabamba (Bolivia in relation to quality of life and living conditions in a neighborhood. The municipality of Cochabamba has embarked upon a mission of rescue and evaluation of the neighborhood organizations, not only incorporating the population into the processes of participation, but also acting in favor of social integration because this stresses the commitment of the neighborhood citizens in the design of the plans. In conclusion, the unfolding experience in the municipality of Cochabamba makes the fact clear that beyond the concept of governability, the search for a co-government-type relation prevails, one that is more horizontal and equitable and where the population takes on a leading role for bringing about the social cohesion and the sense of belonging needed to face the serious problems that afflict Latin American cities.

  14. Citizen Science for public health.

    Science.gov (United States)

    Den Broeder, Lea; Devilee, Jeroen; Van Oers, Hans; Schuit, A Jantine; Wagemakers, Annemarie

    2016-12-23

    Community engagement in public health policy is easier said than done. One reason is that public health policy is produced in a complex process resulting in policies that may appear not to link up to citizen perspectives. We therefore address the central question as to whether citizen engagement in knowledge production could enable inclusive health policy making. Building on non-health work fields, we describe different types of citizen engagement in scientific research, or 'Citizen Science'. We describe the challenges that Citizen Science poses for public health, and how these could be addressed. Despite these challenges, we expect that Citizen Science or similar approaches such as participatory action research and 'popular epidemiology' may yield better knowledge, empowered communities, and improved community health. We provide a draft framework to enable evaluation of Citizen Science in practice, consisting of a descriptive typology of different kinds of Citizen Science and a causal framework that shows how Citizen Science in public health might benefit both the knowledge produced as well as the 'Citizen Scientists' as active participants.

  15. Reconfigurable, Digital EVA Radio Project

    Data.gov (United States)

    National Aeronautics and Space Administration — AeroAstro proposes to develop a low-power, low-volume and lightweight, state-of-the-art digital radio capable of operating in a wide variety of bands, from VHF...

  16. Perception of Citizen Insecurity

    OpenAIRE

    Pillhuamán Caña, Nelly; Universidad Nacional Mayor de San Marcos. Lima - Perú.; Ramos Ramírez, Julio; Universidad Nacional Mayor de San Marcos. Lima - Perú.; Vallenas Ochoa, Guillermo; Universidad Nacional Mayor de San Marcos. Lima - Perú.

    2014-01-01

    This study was carried out in the district of San Juan de Miraflores having as main purpose to obtain reliable information about «perceptions of insecurity and victimization of citizens. The study is a quantitative, descriptive and transversal. The sample design is probabilistic, three-stage, where the final stage unit is the individual whose age is between 16 and 65. The results indicate that in the past six months, 35% of people have been victims of any unlawful act, being theft crime the m...

  17. Radio Journalism.

    Science.gov (United States)

    Bittner, John R.; Bittner, Denise A.

    This book, a how-to-do-it guide for the novice and the professional alike, deals with several aspects of radio journalism: producing documentaries, preparing and announcing radio news, ethics and responsibility, regulation of radio journalism, and careers. It traces the history and growth of radio news, shows its impact on the public, and…

  18. Research and Implementation of Narrow-band Satellite Transceiver Based on GNU Radio%基于GNU Radio的窄带卫星收发信机研究与实现

    Institute of Scientific and Technical Information of China (English)

    林广荣; 林新荣; 高时汉; 褚庆昕

    2016-01-01

    Software defined radio based on general-purpose processor adopts advanced programming language for signal processing, which could help reuse the hardware in different products and improve development efifciency. This paper presented an engineering scheme of narrow-band satellite transceiver on open source GNU Radio platform, and further validated its feasibility by communication testing over actual GEO satellite. The practice provided a new solution for testing terminal equipment, which would aid in the development of satellite communication product.%基于通用处理器的软件无线电技术,使用高级程序语言实现无线电通信中的信号处理功能,这能够更好地复用硬件平台和提升开发效率。文章基于开源的软件无线电平台GNU Radio,给出了一种软件无线电架构的窄带卫星收发信机的工程实现方案,并通过实际上星测试验证了方案的可行性,可为卫星通信产品的研发提供测试和验证的途径。

  19. Perspectives in Marine Citizen Science

    Directory of Open Access Journals (Sweden)

    Michael Bear

    2015-11-01

    Full Text Available Citizen science can be defined as the process by which any non-scientist collects data or uses the scientific method under the guidance or mentorship of a scientist. This article presents an overview of several marine citizen-science projects as practiced by three non-profit organizations.

  20. Perspectives in Marine Citizen Science

    OpenAIRE

    2016-01-01

    Citizen science can be defined as the process by which any non-scientist collects data or uses the scientific method under the guidance or mentorship of a scientist. This article presents an overview of several marine citizen-science projects as practiced by three non-profit organizations.

  1. Amateur Community and ``Citizen Science''

    Science.gov (United States)

    Henden, Arne A.

    2012-04-01

    Citizen Science is the act of collecting or analyzing data by enlisting the help of volunteers who may have no specific scientific training. The workshop discussed how ``Citizen Science'' fits into time-domain astronomy, what the roles of such volunteers might be, and how amateur astronomers can help in the new era of surveys.

  2. Citizen Science Across the Disciplines

    Science.gov (United States)

    Fienberg, R. T.; Gay, P. L.; Lewis, G.; Gold, M.

    2011-09-01

    Astronomers, geologists, ornithologists, and many others across the scientific spectrum have discovered a powerful new tool for conducting research: an army of willing and enthusiastic citizen scientists. Tens of thousands of nonscientists routinely help researchers collect data, analyze it, and even interpret it, enabling scientific investigations that might otherwise be impossible. Many citizen-science projects are developed and conducted at least in part for the purposes of education and outreach, so it is appropriate to ask not only whether they are having a significant scientific impact, but also whether they are having a significant educational one. In this discussion we address issues such as the factors that determine whether a citizen-science project is successful, whether scientists and citizens benefit equally or unequally, and whether citizen science attracts a wide cross section of the public or only people who are already science literate, thereby limiting its effectiveness for EPO.

  3. Citizen centered design

    Directory of Open Access Journals (Sweden)

    Ingrid Mulder

    2015-11-01

    Full Text Available Today architecture has to design for rapidly changing futures, in a citizen-centered way. That is, architecture needs to embrace meaningful design. Societal challenges ask for a new paradigm in city-making, which combines top-down public management with bottom-up social innovation to reach meaningful design. The biggest challenge is indeed to embrace a new collaborative attitude, a participatory approach, and to have the proper infrastructure that supports this social fabric. Participatory design and transition management are future-oriented, address people and institutions. Only through understanding people in context and the corresponding dynamics, one is able to design for liveable and sustainable urban environments, embracing the human scale.

  4. Monitoring System for Atmospheric Water Vapor with a Ground-Based Multi-Band Radiometer: Meteorological Application of Radio Astronomy Technologies

    Science.gov (United States)

    Nagasaki, T.; Araki, K.; Ishimoto, H.; Kominami, K.; Tajima, O.

    2016-08-01

    High-resolution estimation of thermodynamic properties in the atmosphere can help to predict and mitigate meteorological disasters, such as local heavy rainfall and tornadic storms. For the purposes of short-term forecasting and nowcasting of severe storms, we propose a novel ground-based measurement system, which observes the intensity of atmospheric radiation in the microwave range. Our multi-band receiver system is designed to identify a rapid increase in water vapor before clouds are generated. At frequencies between 20 and 30 GHz, our system simultaneously measures water vapor as a broad absorption peak at 22 GHz as well as cloud liquid water. Another band at 50-60 GHz provides supplementary information from oxygen radiation to give vertical profiles of physical temperature. For the construction of this cold receiver system, novel technologies originally developed for observations of cosmic microwave background radiation were applied. The input atmospheric signal is amplified by a cold low-noise amplifier maintained below 10 K, while the spectrum of this amplified signal is measured using a signal analyzer under ambient conditions. The cryostat also contains a cold black body at 40 K to act as a calibration signal. This calibration signal is transported to each of the receivers via a wire grid. We can select either the atmospheric signal or the calibration signal by changing the orientation of this wire. Each receiver can be calibrated using this setup. Our system is designed to be compact (<1 m3), with low power consumption (˜ 1.5 kW). Therefore, it is easy to deploy on top of high buildings, mountains, and ship decks.

  5. Radio emision from supernova remnants

    Science.gov (United States)

    Dubner, G.

    2016-06-01

    The vast majority of supernova remnants (SNRs) in our Galaxy and nearby galaxies have been discovered through radio observations, and only a very small number of the SNRs catalogued in the Milky Way have not been detected in the radio band, or are poorly defined by current radio observations. The study of the radio emission from SNRs is an excellent tool to investigate morphological characteristics, marking the location of shock fronts and contact discontinuities; the presence, orientation and intensity of the magnetic field; the energy spectrum of the emitting particles; and the dynamical consequences of the interaction with the circumstellar and interstellar medium. I will review the present knowledge of different important aspects of radio remnants and their impact on the interstellar gas. Also, new radio studies of the Crab Nebula carried out with the Karl Jansky Very Large Array (JVLA) at 3 GHz and with ALMA at 100 GHz, will be presented.

  6. The faint radio sky: radio astronomy becomes mainstream

    Science.gov (United States)

    Padovani, Paolo

    2016-09-01

    Radio astronomy has changed. For years it studied relatively rare sources, which emit mostly non-thermal radiation across the entire electromagnetic spectrum, i.e. radio quasars and radio galaxies. Now, it is reaching such faint flux densities that it detects mainly star-forming galaxies and the more common radio-quiet active galactic nuclei. These sources make up the bulk of the extragalactic sky, which has been studied for decades in the infrared, optical, and X-ray bands. I follow the transformation of radio astronomy by reviewing the main components of the radio sky at the bright and faint ends, the issue of their proper classification, their number counts, luminosity functions, and evolution. The overall "big picture" astrophysical implications of these results, and their relevance for a number of hot topics in extragalactic astronomy, are also discussed. The future prospects of the faint radio sky are very bright, as we will soon be flooded with survey data. This review should be useful to all extragalactic astronomers, irrespective of their favourite electromagnetic band(s), and even stellar astronomers might find it somewhat gratifying.

  7. Advertising Citizen Science: A Trailer for the Citizen Sky Project

    Science.gov (United States)

    Wyatt, Ryan; Price, A.

    2012-01-01

    Citizen Sky is a multi-year, NSF funded citizen science project involving the bright and mysterious variable star epsilon Aurigae. The project was conceived by the IYA 2009 working group on Research Experiences for Students, Teachers, and Citizen-Scientists. Citizen Sky goes beyond simple observing to include a major data analysis component, introducing participants to the full scientific process from background research to paper writing for a peer-reviewed journal. As a means of generating interest in the project, the California Academy of Sciences produced a six-minute "trailer” formatted for both traditional and fulldome planetariums as well as HD and web applications. This talk will review the production process for the trailer as well as the methods of distribution via planetariums, social media, and other venues_along with an update on the Citizen Sky Project as a whole. We will show how to use a small, professionally-produced planetarium trailer to help spread word on a citizen science project. We will also show preliminary results on a study about how participation level/type in the project affects science learning.

  8. Citizens meetings in democratic system

    Directory of Open Access Journals (Sweden)

    Natalya V. Lebedeva

    2011-01-01

    Full Text Available Citizens meeting is one of the forms of practically applied local self-administration realization by the population. However, it is necessary to carry out further work, concerning perfection of the given institution regulation.

  9. Fiscal State-citizen Alignment

    DEFF Research Database (Denmark)

    Celik, Tim Holst

    2016-01-01

    The 2008 crisis ended the growth bubble of the 2000s, which Organisation for Economic Co-operation and Development (OECD) governments facilitated through the normative/political-regulatory promotion of household indebtedness. Historically contextualizing this state-citizen relationship, this arti......The 2008 crisis ended the growth bubble of the 2000s, which Organisation for Economic Co-operation and Development (OECD) governments facilitated through the normative/political-regulatory promotion of household indebtedness. Historically contextualizing this state-citizen relationship...

  10. The Management of the Citizen Oriented Applications

    OpenAIRE

    Ion IVAN; Bogdan VINTILĂ

    2010-01-01

    The context of the knowledge based society is presented. The new user requirements in the context of the new society are analyzed. Basic concepts regarding the citizen oriented applications are presented. Issues specific to the citizen oriented applications are presented. The development cycle of the citizen oriented applications is analyzed. The particular elements for developing citizen oriented applications are described. The quality concept for the citizen oriented applications is defined...

  11. The LOFAR radio environment

    CERN Document Server

    Offringa, A R; Zaroubi, S; van Diepen, G; Martinez-Ruby, O; Labropoulos, P; Brentjens, M A; Ciardi, B; Daiboo, S; Harker, G; Jelic, V; Kazemi, S; Koopmans, L V E; Mellema, G; Pandey, V N; Pizzo, R F; Schaye, J; Vedantham, H; Veligatla, V; Wijnholds, S J; Yatawatta, S; Zarka, P; Alexov, A; Anderson, J; Asgekar, A; Avruch, M; Beck, R; Bell, M; Bell, M R; Bentum, M; Bernardi, G; Best, P; Birzan, L; Bonafede, A; Breitling, F; Broderick, J W; Bruggen, M; Butcher, H; Conway, J; de Vos, M; Dettmar, R J; Eisloeffel, J; Falcke, H; Fender, R; Frieswijk, W; Gerbers, M; Griessmeier, J M; Gunst, A W; Hassall, T E; Heald, G; Hessels, J; Hoeft, M; Horneffer, A; Karastergiou, A; Kondratiev, V; Koopman, Y; Kuniyoshi, M; Kuper, G; Maat, P; Mann, G; McKean, J; Meulman, H; Mevius, M; Mol, J D; Nijboer, R; Noordam, J; Norden, M; Paas, H; Pandey, M; Pizzo, R; Polatidis, A; Rafferty, D; Rawlings, S; Reich, W; Rottgering, H J A; Schoenmakers, A P; Sluman, J; Smirnov, O; Sobey, C; Stappers, B; Steinmetz, M; Swinbank, J; Tagger, M; Tang, Y; Tasse, C; van Ardenne, A; van Cappellen, W; van Duin, A P; van Haarlem, M; van Leeuwen, J; van Weeren, R J; Vermeulen, R; Vocks, C; Wijers, R A M J; Wise, M; Wucknitz, O

    2012-01-01

    Aims: This paper discusses the spectral occupancy for performing radio astronomy with the Low-Frequency Array (LOFAR), with a focus on imaging observations. Methods: We have analysed the radio-frequency interference (RFI) situation in two 24-h surveys with Dutch LOFAR stations, covering 30-78 MHz with low-band antennas and 115-163 MHz with high-band antennas. This is a subset of the full frequency range of LOFAR. The surveys have been observed with a 0.76 kHz / 1 s resolution. Results: We measured the RFI occupancy in the low and high frequency sets to be 1.8% and 3.2% respectively. These values are found to be representative values for the LOFAR radio environment. Between day and night, there is no significant difference in the radio environment. We find that lowering the current observational time and frequency resolutions of LOFAR results in a slight loss of flagging accuracy. At LOFAR's nominal resolution of 0.76 kHz and 1 s, the false-positives rate is about 0.5%. This rate increases approximately linear...

  12. Radio archive

    OpenAIRE

    Street, Sean

    2008-01-01

    The Centre for Broadcasting History Research, in association with the\\ud British Universities Film and Video Council, is developing an online\\ud audio archive of UK commercial radio, from 1973 to 1992. Work produced\\ud before the Broadcasting Act 1990 represents a different ethos to the role\\ud commercial radio played, and subsequently,continues to play, in the UK.\\ud The change in commercial radio since this period is extraordinary. It is\\ud impossible for the young student of radio, born si...

  13. The Citizen as Issue Specialists in a Changing Media Environment

    Directory of Open Access Journals (Sweden)

    Yong Jin Park

    2013-11-01

    Full Text Available Although recent research suggests that the selective nature of new media helps foster issue specialists, little empirical evidence has been documented, mostly due to theoretical and methodological limitations. Extending the concept of issue publics, the present study proposes a method to estimate the degree to which an individual is a specialist- or a generalist-type citizen. Applying the method to the 2008 American National Election Studies data, the study reveals various characteristics of specialists and generalists. The results indicate that specialist-type citizens are positively associated with online news use, but negatively associated with conventional news media, such as television, newspaper, and radio. The implications of the growth of specialists as well as the validity of the proposed method are discussed.

  14. Dust tori in radio galaxies

    CERN Document Server

    van der Wolk, G; Peletier, R F; Pel, J W

    2009-01-01

    We investigate the validity of the quasar - radio galaxy unification scenario and determine the presence of dust tori among radio galaxies of various types. Actively accreting supermassive black holes in the centres of radio galaxies may be uncovered through their dust tori reradiating the optical and ultraviolet continuum in mid-infrared bands. Using VISIR on the VLT, we have obtained sub-arcsecond (~0.40") resolution N-band images, at a wavelength of 11.85 micron, of the nuclei of a sample of 27 radio galaxies of four types in the redshift range z=0.006-0.156. The sample consists of 8 edge-darkened, low-power Fanaroff-Riley class I (FR-I) radio galaxies, 6 edge-brightened, class II (FR-II) radio galaxies displaying low-excitation optical emission, 7 FR-IIs displaying high-excitation optical emission, and 6 FR-II broad emission line radio galaxies. Out of the sample of 27 objects, 10 nuclei are detected and several have constraining non-detections at 10 sigma sensitivities of 7 mJy. On the basis of the core ...

  15. Microwave radio transmission design guide

    CERN Document Server

    Manning, Trevor

    2009-01-01

    This newly revised second edition provides a current, comprehensive treatment of the subject with a focus on applying practical knowledge to real-world networks. It includes a wealth of important updates, including discussions on backhaul capacity limitations, ethernet over radio, details on the latest cellular radio standards (2.5G, 3G, and 4G). You also learn about recent changes in spectrum management, including the availability of unlicensed bands and new mm band frequencies between 70 and 90 GHz. Additionally, you find more details on the fundamentals of antennas, especially at VHF/UHF le

  16. Risk Communication and Citizen Engagement

    DEFF Research Database (Denmark)

    Merkelsen, Henrik

    2011-01-01

    Despite the last few decades’ devotion to deliberative methods in risk communication, many studies point to how important challenges arise when citizens are engaged in public dialogue. Since the era of enlightenment public dialogue has occupied a position as a normative ideal for political......, their different presumptions about the role of communication symmetry are likely to appear. This points to how the models hold very different expectations as to the dialogical outcome, thus imposing some fundamental conflicts regarding the political efficacy of citizen engagement as a strategy for bridging...

  17. Radio Eska Lodz, Commercial Radio As a Local Radio

    OpenAIRE

    Szews, Przemysław

    2015-01-01

    The article discusses aspects of network-based local radio using the example of Radio Eska Lodz. The author responds to questions about whether a commercial network radio station can fulfill the functions of local radio and on what this locality is actually based. In this respect, Radio Eska Lodz is characterized as part of the most popular commercial radio network in Poland. The introduction focuses on the process of transformation that local radio stations are undergoing, along with its gen...

  18. Ideas for Citizen Science in Astronomy

    Science.gov (United States)

    Marshall, Philip J.; Lintott, Chris J.; Fletcher, Leigh N.

    2015-08-01

    We review the expanding, internet-enabled, and rapidly evolving field of citizen astronomy, focusing on research projects in stellar, extragalactic, and planetary science that have benefited from the participation of members of the public. These volunteers contribute in various ways: making and analyzing new observations, visually classifying features in images and light curves, exploring models constrained by astronomical data sets, and initiating new scientific enquiries. The most productive citizen astronomy projects involve close collaboration between the professionals and amateurs involved and occupy scientific niches not easily filled by great observatories or machine learning methods: Citizen astronomers are motivated by being of service to science, as well as by their interest in the subject. We expect participation and productivity in citizen astronomy to increase, as data sets get larger and citizen science platforms become more efficient. Opportunities include engaging citizens in ever-more advanced analyses and facilitating citizen-led enquiry through professional tools designed with citizens in mind.

  19. National Committee Generates Citizen Participation

    Science.gov (United States)

    Journal of Educational Communication, 1975

    1975-01-01

    This interview with a senior associate of the National Committee for Citizens in Education touches on this organization's accomplishments (such as its work on student records) and on its goals (such as training parent organizations to conduct inquiries into local educational issues). (DS)

  20. Strategies for Training Citizen Advocates.

    Science.gov (United States)

    Nader, Ralph

    1990-01-01

    Training of citizen advocates should include legal rights and remedies; how to get information from corporations and governments; freedom of information laws; use of media; and how to write letters to editors and public officials. Adult educators can help create networks for sharing experience in dealing with community problems. (SK)

  1. Software Defined Multiband EVA Radio Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The objective of this research is to propose a reliable, lightweight, programmable, multi-band, multi-mode, miniaturized frequency-agile EVA software defined radio...

  2. Citizen Involvement in Local Security Networks

    NARCIS (Netherlands)

    Terpstra, J.B.

    2009-01-01

    This paper deals with the involvement of citizens (and local businesspersons) in the prevention and control of crime and disorder. Four models of citizen involvement in local security networks are distinguished. In each of these models the role of citizens concentrates on different functions: (1) p

  3. Developing Citizen Committees for Education Associations.

    Science.gov (United States)

    National Education Association, Washington, DC.

    This booklet is designed for education association leaders for use (a) in providing sole leadership in forming citizen committees when school boards or administrators refuse to permit or encourage citizen participation, or (b) in offering guidelines to the school board or administrators in establishing effective citizen committees. The booklet is…

  4. Educating Citizens in Late Modern Societies

    DEFF Research Database (Denmark)

    Christensen, Torben Spanget

    2011-01-01

    . The model is based on the fundamental belief that the overall aim of civic education in democratic, late modern and global societies is empowerment of the citizen in order to establish a self governing citizen who simultaneous is capable of managing and keeping together partly contradictory citizens tasks...

  5. Developing Citizen Leaders through Action Learning

    Science.gov (United States)

    Foley, Dolores

    2006-01-01

    This is an account of a programmer utilizing the application of action learning to the development of capacities of citizens. The Citizen Leadership for Democratic Governance is designed to equip citizens with the skills to get involved and handle the difficult tasks of governance in their communities in South Africa. After a history of apartheid…

  6. 24 CFR 570.431 - Citizen participation.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 3 2010-04-01 2010-04-01 false Citizen participation. 570.431... CDBG Grants in Hawaii and Insular Areas Programs § 570.431 Citizen participation. (a) General. An... comply with the citizen participation requirements described in this section, including requirements...

  7. 24 CFR 1003.604 - Citizen participation.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 4 2010-04-01 2010-04-01 false Citizen participation. 1003.604... Requirements § 1003.604 Citizen participation. (a) In order to permit residents of Indian tribes and Alaska.... Accordingly, the citizen participation requirements of this section do not include concurrence by any...

  8. Solar Radio

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Scientists monitor the structure of the solar corona, the outer most regions of the Sun's atmosphere, using radio waves (100?s of MHz to 10?s of GHz). Variations in...

  9. Climate change discourses and citizen participation

    DEFF Research Database (Denmark)

    Lassen, Inger; Horsbøl, Anders; Bonnen, Kersten

    2011-01-01

    Citizen participation is a recurrent and democratically important issue in the ongoing debate about climate change. However, different meanings are ascribed to citizen participation in different contexts and discourses, ranging from top-down involvement to bottom-up engagement. This article...... investigates citizen participation as it emerges in two discussion fora, viz. a global forum represented by the international conference Beyond Kyoto, including a vast selection of international actors, and a local forum represented by the municipal project Energy Town Frederikshavn in the northern periphery...... within different research fields, assessing how citizen participation is articulated within these discourses. Finally, we address some needs for increased citizen participation in the climate change debate....

  10. The faint radio sky: radio astronomy becomes mainstream

    CERN Document Server

    Padovani, Paolo

    2016-01-01

    Radio astronomy has changed. For years it studied relatively rare sources, which emit mostly non-thermal radiation across the entire electromagnetic spectrum, i.e. radio quasars and radio galaxies. Now it is reaching such faint flux densities that it detects mainly star-forming galaxies and the more common radio-quiet active galactic nuclei. These sources make up the bulk of the extragalactic sky, which has been studied for decades in the infrared, optical, and X-ray bands. I follow the transformation of radio astronomy by reviewing the main components of the radio sky at the bright and faint ends, the issue of their proper classification, their number counts, luminosity functions, and evolution. The overall "big picture" astrophysical implications of these results, and their relevance for a number of hot topics in extragalactic astronomy, are also discussed. The future prospects of the faint radio sky are very bright, as we will soon be flooded with survey data. This review should be useful to all extragalac...

  11. Miniature EVA Software Defined Radio

    Science.gov (United States)

    Pozhidaev, Aleksey

    2012-01-01

    As NASA embarks upon developing the Next-Generation Extra Vehicular Activity (EVA) Radio for deep space exploration, the demands on EVA battery life will substantially increase. The number of modes and frequency bands required will continue to grow in order to enable efficient and complex multi-mode operations including communications, navigation, and tracking applications. Whether conducting astronaut excursions, communicating to soldiers, or first responders responding to emergency hazards, NASA has developed an innovative, affordable, miniaturized, power-efficient software defined radio that offers unprecedented power-efficient flexibility. This lightweight, programmable, S-band, multi-service, frequency- agile EVA software defined radio (SDR) supports data, telemetry, voice, and both standard and high-definition video. Features include a modular design, an easily scalable architecture, and the EVA SDR allows for both stationary and mobile battery powered handheld operations. Currently, the radio is equipped with an S-band RF section. However, its scalable architecture can accommodate multiple RF sections simultaneously to cover multiple frequency bands. The EVA SDR also supports multiple network protocols. It currently implements a Hybrid Mesh Network based on the 802.11s open standard protocol. The radio targets RF channel data rates up to 20 Mbps and can be equipped with a real-time operating system (RTOS) that can be switched off for power-aware applications. The EVA SDR's modular design permits implementation of the same hardware at all Network Nodes concept. This approach assures the portability of the same software into any radio in the system. It also brings several benefits to the entire system including reducing system maintenance, system complexity, and development cost.

  12. Optical and Radio Variability of BL Lacertae

    CERN Document Server

    Gaur, Haritma; Bachev, R; Strigachev, A; Semkov, E; Wiita, Paul J; Volvach, A E; Gu, Minfeng; Agarwal, A; Agudo, I; Aller, M F; Aller, H D; Kurtanidze, O M; Kurtanidze, S O; Lahteenmaki, A; Peneva, S; Nikolashvili, M G; Sigua, L A; Tornikoski, M; Volvach, L N

    2015-01-01

    We observed the prototype blazar, BL Lacertae, extensively in optical and radio bands during an active phase in the period 2010--2013 when the source showed several prominent outbursts. We searched for possible correlations and time lags between the optical and radio band flux variations using multifrequency data to learn about the mechanisms producing variability. During an active phase of BL Lacertae, we searched for possible correlations and time lags between multifrequency light curves of several optical and radio bands. We tried to estimate any possible variability timescales and inter-band lags in these bands. We performed optical observations in B, V, R and I bands from seven telescopes in Bulgaria, Georgia, Greece and India and obtained radio data at 36.8, 22.2, 14.5, 8 and 4.8 GHz frequencies from three telescopes in Ukraine, Finland and USA. Significant cross-correlations between optical and radio bands are found in our observations with a delay of cm-fluxes with respect to optical ones of ~250 days...

  13. Visual truths of citizen reportage

    DEFF Research Database (Denmark)

    Allan, Stuart; Peters, Chris

    2015-01-01

    In striving to better understand issues associated with citizen contributions to newsmaking in crisis situations, this article identifies and elaborates four specific research problematics – bearing witness, technologies of truth-telling, mediating visualities and affectivities of othering....... Rather than centring analysis on how crisis events highlight change, it discerns the basis for a critical tracing of the material configurations and contingencies shaping journalistic imperatives towards generating visually truthful reportage. In seeking to move debates about how best to enliven digital...

  14. The making of citizen science

    DEFF Research Database (Denmark)

    Brodersen, Søsser

    This dissertation is the result of a PhD project entitled The Making of Citizen Science – Network Alliances between Science Shops and CSOs Engaging in Science and Air Pollution. The PhD project was carried out at Department of Management Engineering, Section for Innovation and Sustainability...... (Training and Mentoring of Science Shops) and in the coming EU-financed project PERARES (Public Engagement with Research and Research Engagement with Society)....

  15. 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

  16. Robust Detection of Incumbents in Cognitive Radio Networks Using Groups

    OpenAIRE

    Rifà Pous, Helena; Jimenez Blasco, Mercedes; Mut Rojas, Jose Carlos

    2011-01-01

    Cognitive radio is a wireless technology aimed at improving the efficiency use of the radio-electric spectrum, thus facilitating a reduction in the load on the free frequency bands. Cognitive radio networks can scan the spectrum and adapt their parameters to operate in the unoccupied bands. To avoid interfering with licensed users operating on a given channel, the networks need to be highly sensitive, which is achieved by using cooperative sensing methods. Current cooperativ...

  17. The Management of the Citizen Oriented Applications

    Directory of Open Access Journals (Sweden)

    Ion IVAN

    2010-04-01

    Full Text Available The context of the knowledge based society is presented. The new user requirements in the context of the new society are analyzed. Basic concepts regarding the citizen oriented applications are presented. Issues specific to the citizen oriented applications are presented. The development cycle of the citizen oriented applications is analyzed. The particular elements for developing citizen oriented applications are described. The quality concept for the citizen oriented applications is defined. Quality characteristics and the costs of quality are defined and analyzed. A system of indicators for the quantification of the quality of the citizen oriented applications is developed. Ways of increasing the quality of the applications are analyzed. Issues as improving the users’ training level, implementing new development techniques, advanced testing techniques and the requirement of audit are approached. The concept of optimization is defined. Optimum criteria are defined and analyzed. Ways of optimizing applications are described. Security requirements are enumerated and described. The particularities of the security requirements for the citizen oriented applications are analyzed. Measures for ensuring the security of the citizen oriented applications are described. A citizen oriented application for the analysis of the structured entities is developed. The application collects data regarding the behavior of the users. The collected data are used for verifying the hypotheses regarding the quality characteristics if the citizen oriented informatics applications.

  18. Metsahovi Radio Observatory - IVS Network Station

    Science.gov (United States)

    Uunila, Minttu; Zubko, Nataliya; Poutanen, Markku; Kallunki, Juha; Kallio, Ulla

    2013-01-01

    In 2012, Metsahovi Radio Observatory together with Finnish Geodetic Institute officially became an IVS Network Station. Eight IVS sessions were observed during the year. Two spacecraft tracking and one EVN X-band experiment were also performed. In 2012, the Metsahovi VLBI equipment was upgraded with a Digital Base Band Converter, a Mark 5B+, a FILA10G, and a FlexBuff.

  19. Kajian implementasi radio siaran digital di Indonesia [Study of digital radio broadcasting implementation in Indonesia

    Directory of Open Access Journals (Sweden)

    Amry Daulat Gultom

    2015-12-01

    Full Text Available Peraturan Menteri Komunikasi dan Informatika RI nomor 21 tahun 2009 tentang  Standar Penyiaran Digital Untuk Penyiaran Radio pada Pita VHF di Indonesia menyatakan bahwa dalam rangka mengatasi permasalahan penggunaan frekuensi VHF Band II untuk penyiaran radio FM yang tidak sesuai dengan rencana induk, serta tidak terpenuhinya permohonan untuk penggunaan kanal frekuensi dari masyarakat, maka perlu dicarikan saluran siaran alternatif dengan menggunakan sistem penyiaran radio digital standard DAB Family. Hingga saat ini belum ada perkembangan berarti terkait implementasinya, sehingga perlu dilakukan penelitian untuk mengetahui potensi radio siaran digital, kesiapan dari sisi pemerintah, operator, dan masyarakat, dan kendala yang dihadapi serta merumuskan strategi yang akan digunakan mengatasinya. Metode analisis yang digunakan adalah SWOT dan TOWS kualitatif dari data wawancara dan studi literatur. Hasil penelitian menunjukkan bahwa pihak stasiun radio sudah siap terhadap digitalisasi radio siaran, pihak pemerintah belum begitu siap karena belum adanya regulasi pendukung Permen Kominfo tentang standard radio digital, dan masyarakat juga belum siap karena kurangnya sosialisasi dan masih susah didapatkannya perangkat penerima siaran radio digital. Pengintegrasian penerima siaran radio digital pada kendaraan bermotor roda empat dan telepon genggam yang baru dapat meningkatkan keberadaan perangkat penerima siaran radio digital.*****The Minister of Communication and Information Regulation number 21 of 2009 on Digital Broadcasting Standards for VHF Band Radio Broadcasting in Indonesia stated that in order to overcome the problems of VHF Band II frequency utilization for FM radio broadcasting that is not in accordance with the master plan, as well as non-fulfillment of the request for frequency channels utilization of the society, neeed to find alternative broadcast channel by DAB Family digital radio broadcasting system. Until now there has no

  20. The Multiwavelength Study of Two Unique Radio Galaxies

    Indian Academy of Sciences (India)

    Nectaria A. B. Gizani; M. A. Garrett; J. P. Leahy

    2002-03-01

    We present the usage of multi-frequency and multi-band radio, VLA, observations as well as X-ray observations in order to study the environment around two powerful radio galaxies, namely Hercules A and 3 C310. We study their environment both in pc- and kpc-scales. We have chosen these two radio galaxies as they present similar and unique characteristics, compared to the ones from our general knowledge about double radio galaxies associated with active galactic nuclei.

  1. Digitale radio

    NARCIS (Netherlands)

    Schiphorst, Roel; Zondervan, L.

    2007-01-01

    Als eerste in Europa heeft Nederland begin december 2006 de omschakeling van analoge naar digitale ethertelevisie gemaakt. Voor de analoge FM-radio is er ook een digitale variant, T-DAB. T-DAB staat voor 'Terrestrial Digital Audio Broadcasting'. Dit artikel gaat verder in op deze techniek en de veld

  2. 47 CFR 15.714 - TV bands database administration fees.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false TV bands database administration fees. 15.714 Section 15.714 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Television Band Devices § 15.714 TV bands database administration fees. (a) A TV bands database...

  3. Galaxy Zoo: Motivations of Citizen Scientists

    CERN Document Server

    Raddick, M Jordan; Gay, Pamela L; Lintott, Chris J; Cardamone, Carie; Murray, Phil; Schawinski, Kevin; Szalay, Alexander S; Vandenberg, Jan

    2013-01-01

    Citizen science, in which volunteers work with professional scientists to conduct research, is expanding due to large online datasets. To plan projects, it is important to understand volunteers' motivations for participating. This paper analyzes results from an online survey of nearly 11,000 volunteers in Galaxy Zoo, an astronomy citizen science project. Results show that volunteers' primary motivation is a desire to contribute to scientific research. We encourage other citizen science projects to study the motivations of their volunteers, to see whether and how these results may be generalized to inform the field of citizen science.

  4. 24 CFR 91.401 - Citizen participation plan.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 1 2010-04-01 2010-04-01 false Citizen participation plan. 91.401... Consolidated Plan § 91.401 Citizen participation plan. The consortium must have a citizen participation plan... entitlement communities, the consortium's citizen participation plan must provide for citizen...

  5. Project Citizen: Promoting Action-Oriented Citizen Science in the Classroom

    Science.gov (United States)

    Green, Carie; Medina-Jerez, William

    2012-01-01

    In recent years, citizen science projects have emerged as a means to involve students in scientific inquiry, particularly in the fields of ecology and environmental science. A citizen scientist is "a volunteer who collects and/or processes data as part of a scientific inquiry" (Silverton 2009, p. 467). Participation in citizen science fosters an…

  6. Sounds energetic: the radio producer's energy minibook

    Energy Technology Data Exchange (ETDEWEB)

    1980-12-01

    The Minibook will be expanded into the final Radio Producer's Energy Sourcebook. Radio producers and broadcasters are asked to contribute ideas for presenting energy knowledge to the public and to be included in the Sourcebook. Chapter One presents a case study suggesting programming and promotion ideas and sample scripts for a radio campaign that revolves around no-cost or low-cost steps listeners can take to increase their home energy efficiency and save money. A variety of other energy topics and suggestions on ways to approach them are addressed in Chapter Two. Chapter Three contains energy directories for Baltimore, Philadelphia, Pittsburg, and Washington, DC. The directories will be expanded in the Sourcebook and will consist of a selection of local public and private sector energy-related organizations and list local experts and organizations and the best Federal, state, and local government programs that can provide consumers and citizens groups with information, technical assistance, and financial support. (MCW)

  7. 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

  8. 47 CFR 90.1213 - Band plan.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Band plan. 90.1213 Section 90.1213 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES PRIVATE LAND... § 90.1213 Band plan. The following channel center frequencies are permitted to be aggregated...

  9. Space Telecommunications Radio System STRS Cognitive Radio

    Science.gov (United States)

    Briones, Janette C.; Handler, Louis M.

    2013-01-01

    Radios today are evolving from awareness toward cognition. A software defined radio (SDR) provides the most capability for integrating autonomic decision making ability and allows the incremental evolution toward a cognitive radio. This cognitive radio technology will impact NASA space communications in areas such as spectrum utilization, interoperability, network operations, and radio resource management over a wide range of operating conditions. NASAs cognitive radio will build upon the infrastructure being developed by Space Telecommunication Radio System (STRS) SDR technology. This paper explores the feasibility of inserting cognitive capabilities in the NASA STRS architecture and the interfaces between the cognitive engine and the STRS radio. The STRS architecture defines methods that can inform the cognitive engine about the radio environment so that the cognitive engine can learn autonomously from experience, and take appropriate actions to adapt the radio operating characteristics and optimize performance.

  10. The Global Citizen Conceptualized: Accommodating Ambiguity

    Science.gov (United States)

    Lilley, Kathleen; Barker, Michelle; Harris, Neil

    2017-01-01

    Universities' aims for educating global citizens are rarely supported by a theoretical underpinning or evidence of outcomes. This study explored how international higher education experts conceptualize the global citizen or related terms representing the "ideal global graduate." A global notion of citizenship was accepted by the majority…

  11. Digital citizens Digital nations: the next agenda

    NARCIS (Netherlands)

    Mulder, A.W. (Bert); Hartog, M.W. (Martijn)

    2015-01-01

    DIGITAL CITIZENS CREATE A DIGITAL NATION Citizens will play the lead role as they – in the next phase of the information society – collectively create a digital nation. Personal adoption of information and communication technology will create a digital infrastructure that supports individual and col

  12. Cable Television: Citizen Participation in Planning.

    Science.gov (United States)

    Yin, Robert K.

    The historical background of citizen participation in local affairs and its relevance at the onset of community concern about cable television are briefly discussed in this report. The participation of citizens, municipal officials, and cable operators in laying the groundwork for a cable system as well as the pros and cons of cable television as…

  13. The challenge of citizen participation for democracy

    NARCIS (Netherlands)

    Biegelbauer, P.; Loeber, A.

    2010-01-01

    The paper starts from the observation that the forms of citizen participation have changed considerably from what could be observed in the 1950s and 1960s. Election turn-outs are falling, grass-roots activities of citizens are on the rise and political commentaries in different forms are proliferati

  14. The Question Each Citizen Must Ask

    Science.gov (United States)

    Levine, Peter

    2016-01-01

    Educating students to be good, informed citizens remains a core purpose of K-12 schools. The purposes of civic education, however, are contested, notes Levine, director of the Center for Information and Research on Civic Learning and Engagement. Levine argues that a citizen is someone who seriously asks, "What should we do?"--someone who…

  15. Tapping the power of Citizen Science, NETLAKE

    NARCIS (Netherlands)

    Seelen, L.; Flaim, Giovanna; Jennings, Eleanor; de Senerpont Domis, Lisette

    2016-01-01

    Citizen science, in which scientists and non-scientists work together on scientific projects, is recognized to be an important tool for public participation and engagement. To be able to tailor citizen science projects to water quality issues, we first investigated the water awareness of people by a

  16. Breaking Barriers through Adventure Based Citizen Diplomacy.

    Science.gov (United States)

    Woodward, Ted

    1991-01-01

    Traces the development of peace-oriented experiential philosophy in both its Western and Soviet contexts, suggesting that adventure-based citizen diplomacy is a valuable means to build bridges between them. Adventure Based Citizen Diplomacy projects are working to decrease the cultural, sociopolitical, and psychological barriers that remain in the…

  17. Experienced discrimination amongst European old citizens

    NARCIS (Netherlands)

    van den Heuvel, Wim J. A.; van Santvoort, Marc M.

    2011-01-01

    This study analyses the experienced age discrimination of old European citizens and the factors related to this discrimination. Differences in experienced discrimination between old citizens of different European countries are explored. Data from the 2008 ESS survey are used. Old age is defined as b

  18. Galaxy Zoo: Motivations of Citizen Scientists

    Science.gov (United States)

    Raddick, M. Jordan; Bracey, Georgia; Gay, Pamela L.; Lintott, Chris J.; Cardamone, Carie; Murray, Phil; Schawinski, Kevin; Szalay, Alexander S.; Vandenberg, Jan

    2013-01-01

    Citizen science, in which volunteers work with professional scientists to conduct research, is expanding due to large online datasets. To plan projects, it is important to understand volunteers' motivations for participating. This paper analyzes results from an online survey of nearly 11000 volunteers in Galaxy Zoo, an astronomy citizen science…

  19. [Citizens: allies of the health system].

    Science.gov (United States)

    Venne, Michel

    2014-03-01

    Many international declarations recognize citizen participation as an important driver of success for health policy; however, in most countries the implementation of this principle has been delayed. Yet well-known phenomena, like ageing and incurred costs, should motivate decision makers to rely more on citizens and make them allies of the system, giving them power and responsibility. Citizens can first exercise this responsibility within the areas of prevention and health promotion. This responsibility then expands to include mutual assistance between community members. It is called upon in the definition of new social norms. It is recognized by the participation of citizens in health care decision-making bodies. Lastly, this responsibility applies when the time comes to choose which health services will be covered by the public system and which will be sent on to private insurers. The reasons to create a space for citizens are many. The methods to do it exist. What is needed is political willpower and means.

  20. Ideas for Citizen Science in Astronomy

    CERN Document Server

    Marshall, Philip J; Fletcher, Leigh N

    2014-01-01

    We review the relatively new, internet-enabled, and rapidly-evolving field of citizen science, focusing on research projects in stellar, extragalactic and solar system astronomy that have benefited from the participation of members of the public, often in large numbers. We find these volunteers making contributions to astronomy in a variety of ways: making and analyzing new observations, visually classifying features in images and light curves, exploring models constrained by astronomical datasets, and initiating new scientific enquiries. The most productive citizen astronomy projects involve close collaboration between the professionals and amateurs involved, and occupy scientific niches not easily filled by great observatories or machine learning methods: citizen astronomers are most strongly motivated by being of service to science. In the coming years we expect participation and productivity in citizen astronomy to increase, as survey datasets get larger and citizen science platforms become more efficient...

  1. Democratic Theory and Citizen Participation

    DEFF Research Database (Denmark)

    Biegelbauer, Peter; Hansen, Janus

    2011-01-01

    Citizen participation in terms of participatory technology assessment (PTA) has caused a lot of debate in science and technology policy. However, there are still many open questions: What is the actual impact of PTA on policy-making? On which normative theory of democracy is the evaluation of PTA...... based and does it make a difference which theory is used? Which framework is appropriate to evaluate the often fuzzy impact of PTA on policy-making? Is PTA actually a central element for policy-making or are other factors much more relevant such as politicians' involvement or the presence of industry...... interests? What is the ‘nature’ of the public in different national and institutional contexts? How are expectations of policy-makers played out in the perceived need for regulation? These issues are addressed in a series of comparative papers in this issue which focus on the regulation...

  2. How deliberation makes better citizens

    DEFF Research Database (Denmark)

    Hansen, Kasper Møller; Normann Andersen, Vibeke

    2007-01-01

    This article presents results from a Danish national Deliberative Poll on the single European currency. A representative sample of 364 Danish citizens assembled to deliberate on Denmark's participation in the single currency. As a quasi-experiment, the Deliberative Poll is an example...... of deliberative democracy. Four research questions regarding these deliberative processes are analyzed: openness and access, the quality of deliberation, efficiency and effectiveness, and publicity and accountability. The participants' responses reflect a deliberative process characterized by considerable changes...... in political opinions as the Poll proceeds, increase in level of knowledge and an improved ability to form reasoned opinions. A mutual understanding on the subject matter prevailed among the participants. At the same time, self-interest and domination also appeared during the deliberative process. The article...

  3. ICTs, Openness and Citizen Perceptions of Government: How Civic Technologies Can Facilitate External Citizen Efficacy

    Directory of Open Access Journals (Sweden)

    Rebecca Rumbul

    2016-12-01

    Full Text Available This article examines whether civic technologies deliver an effective technique for developing the political efficacy of citizens and altering their perceived accountability of governments. Employing a survey-based methodology, a quantitative analysis was performed on the users of civic technology sites in the USA, UK, Kenya and South Africa. The primary question posed is whether the specific citizen monitoring actions facilitated by these sites cause a related effect in altering the extent to which citizens believe that governments are responsive to citizen-audit. The results indicate an enhancement in citizen efficacy and perceptions of government accountability. Notable differences detected in the user demographics between the countries studied demonstrate a wide spectrum of citizen usage; however, with common confidence displayed by respondents in the efficacy of the ICT. The findings indicate that the publication and citizen-audit of government information through civic technologies in developed and developing countries increases feelings of external efficacy and perceived government accountability.

  4. Radio Propagation into Modern Buildings

    DEFF Research Database (Denmark)

    Rodriguez Larrad, Ignacio; Nguyen, Huan Cong; Jørgensen, Niels T.K.

    2014-01-01

    Energy-efficient buildings are gaining momentum in order to comply with the new energy regulations. Especially in northern cold countries, thick reinforced walls and energy-efficient windows composed of several layers of glass plus metal coating are becoming the de facto elements in modern building...... compared to an old building. The measurements are performed for frequencies from 800 MHz to 18 GHz with the aim of identifying the frequency dependence and the impact of the new materials on not only the cellular frequency bands used today (mainly below 3 GHz), but also the potential future bands (above 3...... presented along the paper are useful for future radio network planning considerations....

  5. Radio Galaxy Zoo: host galaxies and radio morphologies for large surveys from visual inspection

    CERN Document Server

    Willett, Kyle W

    2016-01-01

    We present early results from Radio Galaxy Zoo, a web-based citizen science project for visual inspection and classification of images from all-sky radio surveys. The goals of the project are to classify individual radio sources (particularly galaxies with multiple lobes and/or complex morphologies) as well as matching the continuum radio emission to the host galaxy. Radio images come from the FIRST and ATLAS surveys, while matches to potential hosts are performed with infrared imaging from WISE and SWIRE. The first twelve months of classification yielded more than 1 million classifications of more than 60,000 sources. For images with at least 75% consensus by the volunteer classifiers, the accuracy is comparable to visual inspection by the expert science team. Based on mid-infrared colors, the hosts associated with radio emission are primarily a mixture of elliptical galaxies, QSOs, and LIRGs, which are in good agreement with previous studies. The full catalog of radio lobes and their host galaxies will meas...

  6. The radio properties of infrared-faint radio sources

    CERN Document Server

    Middelberg, Enno; Hales, Christopher A; Seymour, Nick; Johnston-Hollitt, Melanie; Huynh, Minh T; Lenc, Emil; Mao, Minnie Y

    2010-01-01

    Infrared-faint radio sources (IFRS) are objects that have flux densities of several mJy at 1.4GHz, but that are invisible at 3.6um when using sensitive Spitzer observations with uJy sensitivities. Their nature is unclear and difficult to investigate since they are only visible in the radio. High-resolution radio images and comprehensive spectral coverage can yield constraints on the emission mechanisms of IFRS and can give hints to similarities with known objects. We imaged a sample of 17 IFRS at 4.8GHz and 8.6GHz with the Australia Telescope Compact Array to determine the structures on arcsecond scales. We added radio data from other observing projects and from the literature to obtain broad-band radio spectra. We find that the sources in our sample are either resolved out at the higher frequencies or are compact at resolutions of a few arcsec, which implies that they are smaller than a typical galaxy. The spectra of IFRS are remarkably steep, with a median spectral index of -1.4 and a prominent lack of spec...

  7. The radio properties of infrared-faint radio sources

    Science.gov (United States)

    Middelberg, E.; Norris, R. P.; Hales, C. A.; Seymour, N.; Johnston-Hollitt, M.; Huynh, M. T.; Lenc, E.; Mao, M. Y.

    2011-02-01

    Context. Infrared-faint radio sources (IFRS) are objects that have flux densities of several mJy at 1.4 GHz, but that are invisible at 3.6 μm when using sensitive Spitzer observations with μJy sensitivities. Their nature is unclear and difficult to investigate since they are only visible in the radio. Aims: High-resolution radio images and comprehensive spectral coverage can yield constraints on the emission mechanisms of IFRS and can give hints to similarities with known objects. Methods: We imaged a sample of 17 IFRS at 4.8 GHz and 8.6 GHz with the Australia Telescope Compact Array to determine the structures on arcsecond scales. We added radio data from other observing projects and from the literature to obtain broad-band radio spectra. Results: We find that the sources in our sample are either resolved out at the higher frequencies or are compact at resolutions of a few arcsec, which implies that they are smaller than a typical galaxy. The spectra of IFRS are remarkably steep, with a median spectral index of -1.4 and a prominent lack of spectral indices larger than -0.7. We also find that, given the IR non-detections, the ratio of 1.4 GHz flux density to 3.6 μm flux density is very high, and this puts them into the same regime as high-redshift radio galaxies. Conclusions: The evidence that IFRS are predominantly high-redshift sources driven by active galactic nuclei (AGN) is strong, even though not all IFRS may be caused by the same phenomenon. Compared to the rare and painstakingly collected high-redshift radio galaxies, IFRS appear to be much more abundant, but less luminous, AGN-driven galaxies at similar cosmological distances.

  8. Practical Assessment of Energy-Based Sensing through Software Defined Radio Devices

    OpenAIRE

    Duarte, Miguel; Furtado, Antonio; Luis, M.; Bernardo, Luis; Dinis, Rui; Oliveira, Rodolfo

    2014-01-01

    Part 18: Telecommunications; International audience; The Cognitive Radio is a solution proposed for the increasing demand of radio spectrum. Usually cognitive radios are adopted by the non-license wireless users, which have a certain degree of cognition in order to only access to a given frequency band when the band is sensed idle. However, these bands and their use must be assessed, to avoid interfering with licensed users (primary users). The way to assess band’s occupancy is by discerning ...

  9. Citizen Science in the Internet Age

    Science.gov (United States)

    Raddick, Jordan

    2008-09-01

    The development of new web technologies has led to new opportunities in citizen science, a way of working in which non-professional "citizen scientists" contribute to authentic science research in a meaningful way. Citizen science has been around for a long time - members of the American Association of Variable Star Observers have been collecting and interpreting high-quality scientific data since the organization's founding in 1911. The most famous citizen science project of the computer age was SETI@home, in which volunteers installed a screen saver to process data from the SETI project. Over the last few years, "crowdsourcing" - sending work to large groups of online volunteers - allows previously intractable computer problems such as image classification and language translation to be solved by humans. Application of crowdsourcing methods to citizen science problems has led to programs like Clickworkers (in which volunteers identify Martian craters), Stardust@home (in which volunteers search for tracks of dust impacts), and the project I work on, Galaxy Zoo (in which volunteers classify galaxies as spiral or elliptical). In this talk, I will trace the evolution of citizen science, share some conclusions and lessons learned from the development of Galaxy Zoo, and propose future projects and research directions for citizen science.

  10. Infrared imaging of WENSS radio sources

    CERN Document Server

    Villani, D

    1999-01-01

    We have performed deep imaging in the IR J- and K-bands for three sub-samples of radio sources extracted from the Westerbork Northern Sky Survey, a large low-frequency radio survey containing Ultra Steep Spectrum (USS), Gigahertz Peaked Spectrum (GPS) and Flat Spectrum (FS) sources. We present the results of these IR observations, carried out with the ARcetri Near Infrared CAmera (ARNICA) at the Nordic Optical Telescope (NOT), providing photometric and morphologic information on high redshift radio galaxies and quasars. We find that the radio galaxies contained in our sample do not show the pronounced radio/IR alignment claimed for 3CR sources. IR photometric measurements of the gravitational lens system 1600+434 are also presented.

  11. Analysis and Modeling of Jovian Radio Emissions Observed by Galileo

    Science.gov (United States)

    Menietti, J. D.

    2003-01-01

    Our studies of Jovian radio emission have resulted in the publication of five papers in refereed journals, with three additional papers in progress. The topics of these papers include the study of narrow-band kilometric radio emission; the apparent control of radio emission by Callisto; quasi-periodic radio emission; hectometric attenuation lanes and their relationship to Io volcanic activity; and modeling of HOM attenuation lanes using ray tracing. A further study of the control of radio emission by Jovian satellites is currently in progress. Abstracts of each of these papers are contained in the Appendix. A list of the publication titles are also included.

  12. SUPPORTING SENIOR CITIZENS TO LEARN IT SKILLS

    Directory of Open Access Journals (Sweden)

    Shigeki Yokoi

    2009-12-01

    Full Text Available Digital divide owing to age has become a major concern around the world, even in developed country, Japan. To combat the digital divide, a project named “e-namokun” aiming to help senior citizens use the Internet was started in Nagoya, Japan, which was a national first joint project run through government, universities, and NPO cooperation. In the project, nearly 2000 senior citizens have taken course of the software we developed. In relation with this project, we have been developing useful tools to support senior IT beginners. In the paper, we introduce the outline of the project and explain developed tools for senior citizens.

  13. University Student Groups and Citizen Education

    Directory of Open Access Journals (Sweden)

    JUANITA HENAO-ESCOVAR

    2008-12-01

    Full Text Available The article presents some advances of the research project on Practices of the Youth as Citizen Expressions. From the analysis of three university student groups taken from the 20 groups of youths that participate in this mixed method combining ethnographic strategies with narrative and discursive analysis, the article describes the trajectory and the practices of these groups and shows how the students live experiences that ease the development of different citizen expressions and abilities. The conclusions state that the creation, support and agency of these groups in the universities represent a way to encourage the formation of citizens, and some suggestions are presented related to this topic.

  14. Radio astronomy from space

    Science.gov (United States)

    Woan, G.

    2011-04-01

    At frequencies below about 30 MHz, radio astronomy becomes increasingly difficult from the Earth's surface, mainly due to a combination of poor ionospheric seeing and strong terrestrial interference. The obvious move is to space, either as free-flying spacecraft or with a telescope located somewhere on the Moon. All the major space agencies have a renewed interest in the Moon as a site for exploration and science, and low-frequency radio astronomy is probably the strongest of the astronomical objectives put forward in these programmes. Although the Sun is a strong source of interference in extra-solar system work, it is also a prime target for study in itself. A constellation of satellites (as proposed for the SIRA mission) would be able to image both the Sun and the inner heliosphere over the entire low-frequency band. Here we investigate some of the advantages and limitations of astronomy at these very low frequencies, using space- and lunar-based antennas.

  15. Citizen Participation in Deliberative Global Governance

    DEFF Research Database (Denmark)

    Jæger, Birgit

    The global event World Wide Views on Global Warming (WWViews), initiated by the Danish Board of Technology (DBT), took place on September 26, 2009, and was an attempt to gather a united citizen voice on a global scale. The purpose of WWViews was to pass on the opinions of ordinary citizens...... to political decision-makers at The United Nations Climate Summit, COP 15, in Copenhagen in December 2009. As such the WWViews was an innovative experiment with public engagement in science and technology, aiming to create a ‘global citizen voice’ on climate change. The deliberation took place at 44 different...... places in 38 nations throughout the world. Each place around 100 citizens deliberated four themes of global warming and afterwards they voted on answers to central questions. In the end of the day the participants formulated their main recommendations to pass on to the COP 15 summit. The results...

  16. Citizens for new Europe / Erkki Vedder

    Index Scriptorium Estoniae

    Vedder, Erkki

    2004-01-01

    Peipsi Koostöö Keskus osales partnerina Aktiivsete Kodanike Võrgustiku (Active Citizens Network) algatatud üleeuroopalises projektis, kus uuriti kodanikeühenduste olukorda ning kolmandat sektorit puudutavat seadusandlust erinevates riikides

  17. Maui Citizen Science Coastal Water Quality Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A network of citizen science volunteers periodically monitors water quality at several beaches across the island of Maui in the State of Hawaii. This community-based...

  18. The challenge of citizen participation to democracy

    OpenAIRE

    Biegelbauer, Peter; Loeber, Anne

    2010-01-01

    "The paper starts from the observation that the forms of citizen participation have changed considerably from what could be observed in the 1950s and 1960s. Election turn-outs are falling, grass-roots activities of citizens are on the rise and political commentaries in different forms are proliferating on the Internet. How can we conceptualise modern democratic systems and forms of participation? How helpful is democracy theory for this endeavour? The paper revisits classic and post-modern mo...

  19. PREPARING CITIZENS AS ACTIVE PARTICIPATORS IN E-GOVERNANCE: THE MAKING OF E-CITIZENS

    Directory of Open Access Journals (Sweden)

    DIMPI SRIVASTAVA,

    2010-09-01

    Full Text Available Though E-Government initiatives in India have gained momentum in the past decade, the citizen participation is missing. Geographical, social, & economical disparities among citizens are the biggest barriers for e-governance. Illiteracy, lack of infrastructure, security and privacy of personal and financial data are other constraints that hamper e-governance efforts. Citizens’ participation should be increased against these constraints if we want good returns on investment from our e-governance efforts. The most benefits will be achieved if the e-governance is citizen-centric which itself will transform citizens to become active participators in establishing e-democracy.

  20. 24 CFR 91.105 - Citizen participation plan; local governments.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 1 2010-04-01 2010-04-01 false Citizen participation plan; local... Citizen Participation and Consultation § 91.105 Citizen participation plan; local governments. (a) Applicability and adoption of the citizen participation plan. (1) The jurisdiction is required to adopt...

  1. 24 CFR 91.115 - Citizen participation plan; States.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 1 2010-04-01 2010-04-01 false Citizen participation plan; States... Participation and Consultation § 91.115 Citizen participation plan; States. (a) Applicability and adoption of the citizen participation plan. (1) The State is required to adopt a citizen participation plan...

  2. The RadioSat (sm) network

    Science.gov (United States)

    Noreen, Gary K.

    1991-09-01

    The RadioSat network under development by radio Satellite Corporation will use mobile satellite (MSAT) technology to provide diverse personal communications, broadcast, and navigation services. The network will support these services simultaneously for integrated mobile radios throughout Canada and the United States. The RadioSat network takes advantage of several technological breakthroughs, all coming to fruition by the time the first MSAT satellite is launched in 1994. The most important of these breakthroughs is the enormous radiated power of each MSAT spacecraft - orders of magnitude greater than the radiated power of previous L-band spacecraft. Another important breakthrough is the development of advanced digital audio compression algorithms, enabling the transmission of broadcast quality music at moderate data rates. Finally, continuing dramatic increases in VLSI capabilities permit the production of complex, multi-function mobile satellite radios in very large quantities at prices little more than those of conventional car radios. In addition to performance breakthroughs and their economic implications to RadioSat, the design of the RadioSat network is reviewed.

  3. Detection and Estimation Techniques in Cognitive Radio

    OpenAIRE

    Shen, Juei-Chin

    2013-01-01

    Faced with imminent spectrum scarcity largely due to inflexible licensed band arrangements, cognitive radio (CR) has been proposed to facilitate higher spectrum utilization by allowing cognitive users (CUs) to access the licensed bands without causing harmful interference to primary users (PUs). To achieve this without the aid of PUs, the CUs have to perform spectrum sensing reliably detecting the presence or absence of PU signals. Without reliable spectrum sensing, the discovery of spectrum ...

  4. S-Band propagation measurements

    Science.gov (United States)

    Briskman, Robert D.

    1994-08-01

    A geosynchronous satellite system capable of providing many channels of digital audio radio service (DARS) to mobile platforms within the contiguous United States using S-band radio frequencies is being implemented. The system is designed uniquely to mitigate both multipath fading and outages from physical blockage in the transmission path by use of satellite spatial diversity in combination with radio frequency and time diversity. The system also employs a satellite orbital geometry wherein all mobile platforms in the contiguous United States have elevation angles greater than 20 deg to both of the diversity satellites. Since implementation of the satellite system will require three years, an emulation has been performed using terrestrial facilities in order to allow evaluation of DARS capabilities in advance of satellite system operations. The major objective of the emulation was to prove the feasibility of broadcasting from satellites 30 channels of CD quality programming using S-band frequencies to an automobile equipped with a small disk antenna and to obtain quantitative performance data on S-band propagation in a satellite spatial diversity system.

  5. Cognitive Radio baseband processing on a reconfigurable platform

    NARCIS (Netherlands)

    Zhang, Qiwei; Kokkeler, A.B.J.; Smit, G.J.M.; Walters, K.H.G.; Zhang, Qiwei

    2009-01-01

    Cognitive Radio is considered as a promising technology to address the paradox of spectrum scarcity and spectrum under-utilization. It has to operate in different bands under various data rates and combat adversary channel conditions. Therefore, Cognitive Radio needs an adaptive physical layer which

  6. Software defined radio receivers exploiting noise cancelling: a tutorial review

    NARCIS (Netherlands)

    Klumperink, Eric; Nauta, Bram

    2014-01-01

    Traditional radio receivers were narrowband and dedicated to a single frequency band exploiting LC tanks, whereas software defined radios target a flexibly programmable frequency. The broadband noise cancelling circuit technique has proven useful to achieve this target, as it breaks the traditional

  7. A Proof-of-concept demonstrator for Cognitive Radio

    NARCIS (Netherlands)

    Heskamp, Marnix; Hoeksema, Fokke; Schiphorst, Roel; Slump, Kees

    2005-01-01

    The Adaptive Ad-hoc Free Band Wireless Communications (AAF) project is researching the possibility of using Software Defined Radio for wireless networks that needs to operate in an unknown or even hostile radio environment. Each node in the network needs to be cognitive of nearby transceivers in ord

  8. Physical layer bootstrapping protocol for cognitive radio networks

    NARCIS (Netherlands)

    Doost-Mohammady, R.; Paweczak, P.; Janssen, G.J.M.; Segers, J.C.M.

    2010-01-01

    In this paper a novel signaling protocol for coexistence and spectrum sharing among cognitive radio nodes is proposed. This protocol allows the radios to rendezvous with each other in a statically allocated spectrum band through on-off keying signaling and reliable spectrum sensing. It enables the r

  9. THE ANALYSIS OF INFORMATICS SECURITY COSTS IN CITIZEN ORIENTED APPLICATIONS

    OpenAIRE

    Dragos Palaghita; Bogdan Vintila

    2010-01-01

    The paper highlights the analysis of informatics security costs for the citizen oriented applications. The citizen oriented informatics applications are defined. The differences brought by these when compared with the traditional applications are described. Structures of citizen oriented informatics applications are presented. A few common citizen oriented applications are discussed. The special security requirements of the citizen oriented applications are discussed. Ways of increasing the s...

  10. The Citizen Science Landscape: From Volunteers to Citizen Sensors and Beyond

    Directory of Open Access Journals (Sweden)

    Christina L. Catlin-Groves

    2012-01-01

    Full Text Available Within conservation and ecology, volunteer participation has always been an important component of research. Within the past two decades, this use of volunteers in research has proliferated and evolved into “citizen science.” Technologies are evolving rapidly. Mobile phone technologies and the emergence and uptake of high-speed Web-capable smart phones with GPS and data upload capabilities can allow instant collection and transmission of data. This is frequently used within everyday life particularly on social networking sites. Embedded sensors allow researchers to validate GPS and image data and are now affordable and regularly used by citizens. With the “perfect storm” of technology, data upload, and social networks, citizen science represents a powerful tool. This paper establishes the current state of citizen science within scientific literature, examines underlying themes, explores further possibilities for utilising citizen science within ecology, biodiversity, and biology, and identifies possible directions for further research. The paper highlights (1 lack of trust in the scientific community about the reliability of citizen science data, (2 the move from standardised data collection methods to data mining available datasets, and (3 the blurring of the line between citizen science and citizen sensors and the need to further explore online social networks for data collection.

  11. Band Together!

    Science.gov (United States)

    Olson, Cathy Applefeld

    2011-01-01

    After nearly a decade as band director at St. James High School in St. James, Missouri, Derek Limback knows that the key to building a successful program is putting the program itself above everything else. Limback strives to augment not only his students' musical prowess, but also their leadership skills. Key to his philosophy is instilling a…

  12. Study on Radio Frequency Interference Signal Analysis and Suppression in P Band SAR%P波段SAR射频干扰信号分析及抑制方法研究

    Institute of Scientific and Technical Information of China (English)

    丁斌; 梁兴东; 向茂生

    2012-01-01

    分析了实测P波段SAR静默接收数据,研究了模拟电视信号的频谱特性.针对P波段SAR回波中的模拟电视干扰信号,提出了一种新的干扰抑制方法.通过在时域拼接多个脉冲的回波数据增加模拟电视信号的观测时间以提高频率分辨率,进而在距离频域对其准确识别.根据模拟电视信号的频谱特征,在距离频域构造滤波器组滤除模拟电视信号的离散谱线,保留了谱线间SAR回波信号的频谱分量.实际回波数据的成像处理结果验证了方法的有效性.%Both P band SAR received silent data and spectrum characteristics of analog television signal are analyzed. In order to suppress analog television signals in P band SAR echoes, a novel interference suppression algorithm is proposed. By splicing multi-pulse SAR echoes in time domain, high frequency resolution of analog television signal can be obtained. Therefore the analog television signal can be identified accurately. By designing filter bank in range-frequency domain according to spectrum characteristics of analog television signals, the discrete spectrum lines of analog television signals are removed and the spectrum of SAR echoes between these discrete spectrum lines are saved. Finally, the proposed algorithm is verified by processing real P band SAR data.

  13. 47 CFR 90.656 - Responsibilities of base station licensees of Specialized Mobile Radio systems.

    Science.gov (United States)

    2010-10-01

    ... Specialized Mobile Radio systems. 90.656 Section 90.656 Telecommunication FEDERAL COMMUNICATIONS COMMISSION... Bands § 90.656 Responsibilities of base station licensees of Specialized Mobile Radio systems. (a) The licensees of base stations that provide Specialized Mobile Radio service on a commercial basis of the use...

  14. Radio frequency detection assembly and method for detecting radio frequencies

    Science.gov (United States)

    Cown, Steven H.; Derr, Kurt Warren

    2010-03-16

    A radio frequency detection assembly is described and which includes a radio frequency detector which detects a radio frequency emission produced by a radio frequency emitter from a given location which is remote relative to the radio frequency detector; a location assembly electrically coupled with the radio frequency detector and which is operable to estimate the location of the radio frequency emitter from the radio frequency emission which has been received; and a radio frequency transmitter electrically coupled with the radio frequency detector and the location assembly, and which transmits a radio frequency signal which reports the presence of the radio frequency emitter.

  15. Observations of Radio Giant Pulses with GAVRT

    CERN Document Server

    Jones, Glenn

    2015-01-01

    Radio giant pulses provide a unique opportunity to study the pulsar radio emission mechanism in exquisite detail. Previous studies have revealed a wide range of properties and phenomena, including extraordinarily high brightness temperatures, sub-nanosecond emission features, and banded dynamic spectra. New measurements of giant pulse characteristics can help guide and test theoretical emission models. To this end, an extensive observation campaign has begun which will provide more than 500 hours on the Crab with a 34-meter antenna located in California, USA. The observations are being done as part of an educational outreach program called the Goldstone-Apple Valley Radio Telescope (GAVRT). This antenna has a novel wide bandwidth receiver which provides up to 8 GHz of instantaneous bandwidth in the range of 2.5 to 14 GHz. These observations will provide detailed information about the variability, amplitude distribution, and detailed frequency structure of radio giant pulses. In addition, a database of pulses ...

  16. Citizen Science and the Modern Web

    CERN Document Server

    CERN. Geneva

    2014-01-01

    Beginning as a research project to help scientists communicate, the Web has transformed into a ubiquitous medium. As the sciences continue to transform, new techniques are needed to analyze the vast amounts of data being produced by large experiments. The advent of the Sloan Digital Sky Survey increased throughput of astronomical data, giving rise to Citizen Science projects such as Galaxy Zoo. The Web is no longer exclusively used by researchers, but rather, a place where anyone can share information, or even, partake in citizen science projects. As the Web continues to evolve, new and open technologies enable web applications to become more sophisticated. Scientific toolsets may now target the Web as a platform, opening an application to a wider audience, and potentially citizen scientists. With the latest browser technologies, scientific data may be consumed and visualized, opening the browser as a new platform for scientific analysis.

  17. What Kind of Citizen for Europe?

    Directory of Open Access Journals (Sweden)

    Stéphane Caporal

    2010-07-01

    Full Text Available The citizen is characterized by its affiliation to a democratic order, but we need to know if this order allows building citizenship. If the political participation manifests legally the right to citizenship, for Alain Touraine, a citizen is "to feel the responsibility for the smooth functioning of institutions that obey the human rights and which it allows a representation of ideas and interests.”, which is a lot, but it does not imply a moral or national conscience. The accuracy on human rights raises a question on its epistemological status: is it a socially acceptable condition for nowadays or is it a substantial condition of concept’s existence, in which case we should believe that the Greeks andthe Romans knew what a citizen was.

  18. The citizens in E-participation

    DEFF Research Database (Denmark)

    Hansen, Henning Sten; Reinau, Kristian Hegner

    2006-01-01

    Recent advances in GIS and the Internet have improved the technical possibilities for supporting the public participation through e-Participation systems - e.g. Public Participation GIS. On the other hand there has been too much focus on many technical aspects of public participation with reduced...... focus on the citizens. Equal opportunities to express their opinions and an open debate between people are the basic foundation for democracy. Therefore the design of participatory processes must take outset in the citizens and their knowledge and commitment concerning the issue to be debated....... The current paper presents the results of a survey among actively involved citizens in Northern Jutland County. Our analysis shows a high degree of involvement among middle-age well-educated males with a higher education and income above average. It seems that contrary to the planner's vision of an open...

  19. Citizen Science: Contributions to Astronomy Research

    CERN Document Server

    Christian, Carol; Smith, Arfon; Fortson, Lucy; Bamford, Steven

    2012-01-01

    The contributions of everyday individuals to significant research has grown dramatically beyond the early days of classical birdwatching and endeavors of amateurs of the 19th century. Now people who are casually interested in science can participate directly in research covering diverse scientific fields. Regarding astronomy, volunteers, either as individuals or as networks of people, are involved in a variety of types of studies. Citizen Science is intuitive, engaging, yet necessarily robust in its adoption of sci-entific principles and methods. Herein, we discuss Citizen Science, focusing on fully participatory projects such as Zooniverse (by several of the au-thors CL, AS, LF, SB), with mention of other programs. In particular, we make the case that citizen science (CS) can be an important aspect of the scientific data analysis pipelines provided to scientists by observatories.

  20. [Can tobacco companies be good corporate citizens?].

    Science.gov (United States)

    Palazzo, G; Mena, S

    2009-07-01

    Tobacco companies have jumped on the Corporate social responsibility (CSR) bandwagon as a tentative to be societally accepted as responsible actors and good corporate citizens. This is however not possible for two reasons. First, the product they sell is lethal and thus not compatible with the precondition of doing no harm to be a good corporate citizen. Second, the behavior of tobacco firms is not responsible, being illustrated by four examples: junk science versus sound science strategy, seducing young smokers, political lobbying and getting customers on new markets. To conclude, three implications for regulating the activities of the tobacco industry are given.

  1. Power to the people? Restoring citizen participation.

    Science.gov (United States)

    Morone, James A; Kilbreth, Elizabeth H

    2003-01-01

    This article investigates a lost ideal--citizen participation in health policy. We begin by mapping the different types of participation. We then suggest what direct citizen action has achieved in the past, why it ought to be restored today, and how we might go about reviving it. A changing social environment--marked by globalization, immigration, a culture war, and managed care--could be addressed by robust, local, democratic health reforms. Finally, we contrast the top-down health sector with education and crime policies that take communities far more seriously.

  2. Calibration of the solar radio spectrometer

    Institute of Scientific and Technical Information of China (English)

    TAN ChengMing; YAN YiHua; TAN BaoLin; XU GuiRong

    2009-01-01

    This paper shows some improvements and new results of calibration of Chinese solar radio spectrom-eter by analyzing the daily calibration data recorded in the period of 1997-2007. First, the calibration coefficient is fitted for three bands (1.0-2.0 GHz, 2.6-3.8 GHz, 5.2-7.6 GHz) of the spectrometer by using the moving-average method confined by the property of the daily calibration data. By this calibration coefficient, the standard deviation of the calibration result was less than 10 sfu for 95% frequencies of 2.6-3.8 GHz band in 2003. This result is better than that calibrated with the constant coefficient. Second, the calibration coefficient is found in good correlation with local air temperature for most frequencies of 2.6-3.8 GHz band. Moreover, these results are helpful in the research of the quiet solar radio emission.

  3. Calibration of the solar radio spectrometer

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    This paper shows some improvements and new results of calibration of Chinese solar radio spectrometer by analyzing the daily calibration data recorded in the period of 1997-2007. First, the calibration coefficient is fitted for three bands (1.0-2.0 GHz, 2.6-3.8 GHz, 5.2-7.6 GHz) of the spectrometer by using the moving-average method confined by the property of the daily calibration data. By this calibration coefficient, the standard deviation of the calibration result was less than 10 sfu for 95% frequencies of 2.6-3.8 GHz band in 2003. This result is better than that calibrated with the constant coefficient. Second, the calibration coefficient is found in good correlation with local air temperature for most frequencies of 2.6-3.8 GHz band. Moreover, these results are helpful in the research of the quiet solar radio emission.

  4. Tecnologia radio cognitiva en la banda ultra high frequency (UHF

    Directory of Open Access Journals (Sweden)

    Hernán Paz Penagos

    2014-01-01

    Full Text Available Mobile cellular communication companies in Colombia require more spectrum resources to expand their portfolio of services. However, additional frequency bands for that particular purpose are scarce, yet it is well known that there are many underutilized licensed bands. Therefore new radio technologies are being studied in order to solve this problem, e.g. Software Defined Radio SDR Cognitive Radio CR and Dynamic Spectrum Access DSA. These strategies recommend mobility across the radio spectrum to meet various needs and achieve greater efficiency when managing such a scarce resource. In this context, a case study is presented in an attempt to examine the require¬ments that must be met for the implementation of cognitive radio networks in Bogota. The case study includes evaluation for the possibility of migration from cellular communications to cognitive radio since the bands assigned to UltraHigh Frequency UHF television offer possible free-of-interference coexistence between the two services (i.e. Cellular and TV. The study shows feasibility to migration; however, the implementations of cognitive radio need availability of hardware, software and flexible radio platforms.

  5. Fossil shell emission in dying radio loud AGNs

    CERN Document Server

    Kino, M; Kawakatu, N; Orienti, M; Nagai, H; Wajima, K; Itoh, R

    2015-01-01

    We investigate shell emission associated with dying radio loud AGNs. First, based on our recent work by Ito et al. (2015), we describe the dynamical and spectral evolutions of shells after stopping the jet energy injection. We find that the shell emission overwhelms that of the radio lobes soon after stopping the jet energy injection because fresh electrons are continuously supplied into the shell via the forward shock while the radio lobes rapidly fade out without jet energy injection. We find that such fossil shells can be a new class of target sources for SKA telescope. Next, we apply the model to the nearby radio source 3C84. Then, we find that the fossil shell emission in 3C84 is less luminous in radio band while it is bright in TeV gamma-ray band and it can be detectable by CTA.

  6. 基于L波段Stokes参数遥感数据射频干扰检测及特性分析%Radio Frequency Interference Detection and Characteristic Analysis Based on the L Band Stokes Parameters Remote Sensing Data

    Institute of Scientific and Technical Information of China (English)

    王新新; 王祥; 韩震; 杨建洪

    2015-01-01

    近岸海域盐度卫星微波遥感精度受射频干扰(RFI)严重影响,针对近岸海域检测RFI源并分析其影响特性对后续开展射频干扰抑制研究具有重要意义。该文基于SMOS卫星传感器MIRAS 独特的全极化特性,以中国海域沿岸陆地为研究区域,通过合成第3、第4 Stokes参数来表征RFI源的辐射强度,生成了RFI源分布图并分析了其影响范围。研究结果表明,影响中国海域的 RFI 源主要分布于中国沿海陆地区域,渤、黄海全部、东海的西部及南海的北部受RFI污染严重,卫星降轨数据和升轨数据受RFI影响具有很大的差异性。RFI源主要可能是微波发射站,表现为点状射线源,受天线辐射旁瓣的影响,会导致其周围数百公里区域卫星数据污染,并且由于受RFI源辐射衰减和天线辐射方向图各异等因素的影响,导致其对卫星的影响极其复杂,抑制其影响也具有一定的挑战性。%Sea surface salinity remote sensing is seriously impacted by Radio Frequency Interference (RFI) over coastal areas, detecting RFI sources and analyzing its influence characteristic for developing RFI suppression research in the nearshore areas is of great significance. Based on the unique multi-angle observation imaging and polarization characteristics of the SMOS satellite sensor MIRAS, this paper generates the RFI sources distribution diagram and analyzes its distribution characteristics and influence scope through synthesis third and fouth Stokes parameters in the China sea. The results indicate that the RFI sources are concentrated distributed throughout coastal land areas of the Bohai sea, the Yellow sea, the west of the East China Sea and the north of the south China sea are strong impacted by RFI sources, and the sources have big different effects on ascending pass and descending pass data. The RFI sources may be microwave emission station, displaying as pointlike radio source, and the

  7. DNA strand breaks are not induced in human cells exposed to 2.1425 GHz band CW and W-CDMA modulated radiofrequency fields allocated to mobile radio base stations.

    Science.gov (United States)

    Sakuma, N; Komatsubara, Y; Takeda, H; Hirose, H; Sekijima, M; Nojima, T; Miyakoshi, J

    2006-01-01

    We conducted a large-scale in vitro study focused on the effects of low level radiofrequency (RF) fields from mobile radio base stations employing the International Mobile Telecommunication 2000 (IMT-2000) cellular system in order to test the hypothesis that modulated RF fields may act as a DNA damaging agent. First, we evaluated the responses of human cells to microwave exposure at a specific absorption rate (SAR) of 80 mW/kg, which corresponds to the limit of the average whole body SAR for general public exposure defined as a basic restriction in the International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines. Second, we investigated whether continuous wave (CW) and Wideband Code Division Multiple Access (W-CDMA) modulated signal RF fields at 2.1425 GHz induced different levels of DNA damage. Human glioblastoma A172 cells and normal human IMR-90 fibroblasts from fetal lungs were exposed to mobile communication frequency radiation to investigate whether such exposure produced DNA strand breaks in cell culture. A172 cells were exposed to W-CDMA radiation at SARs of 80, 250, and 800 mW/kg and CW radiation at 80 mW/kg for 2 and 24 h, while IMR-90 cells were exposed to both W-CDMA and CW radiations at a SAR of 80 mW/kg for the same time periods. Under the same RF field exposure conditions, no significant differences in the DNA strand breaks were observed between the test groups exposed to W-CDMA or CW radiation and the sham exposed negative controls, as evaluated immediately after the exposure periods by alkaline comet assays. Our results confirm that low level exposures do not act as a genotoxicant up to a SAR of 800 mW/kg.

  8. Impact of cognitive radio on radio astronomy

    NARCIS (Netherlands)

    Bentum, M.J.; Boonstra, A.J.; Baan, W.A.

    2010-01-01

    The introduction of new communication techniques requires an increase in the efficiency of spectrum usage. Cognitive radio is one of the new techniques that fosters spectrum efficiency by using unoccupied frequency spectrum for communications. However, cognitive radio will increase the transmission

  9. Resonance and Radio

    Science.gov (United States)

    Starrett, Malin J.

    2008-01-01

    The science and technology of radio receives little attention in contemporary education. This article discusses ways to explore the basic operating principles of radio. (Contains 4 figures, 3 footnotes, and 2 notes.)

  10. Citizens Science for Sustainability (SuScit) Project Briefing

    DEFF Research Database (Denmark)

    Eames, Malcolm; Mortensen, Jonas Egmose; Adebowale, Maria;

    This project briefing gives a short overview of the Citizens Science for Sustainability (SuScit) Project.......This project briefing gives a short overview of the Citizens Science for Sustainability (SuScit) Project....

  11. Delineating active citizenship: The subjectification of citizens' initiatives

    NARCIS (Netherlands)

    Dam, van R.I.; Duineveld, M.; During, R.

    2015-01-01

    Based on three case studies on citizens' initiatives in their local governance contexts, we analyse the process of subjectification as a performative effect of the dialectical relationship between governmental organizations and citizens' initiatives. We argue that discourses produced by governmental

  12. Critical moments in police-citizen reconciliation

    NARCIS (Netherlands)

    Stronks, Sara; Adang, Otto M. J.

    2015-01-01

    Purpose - The purpose of this paper is to analyze the interaction of police and citizen representatives during critical moments in reconciliation processes through a relational model. Design/methodology/approach - Based on 26 in-depth interviews with key actors in three different cases of media-sali

  13. Sorting Citizens: Differentiated Citizenship Education in Singapore

    Science.gov (United States)

    Ho, Li-Ching

    2012-01-01

    Using Singapore as a case study, this paper examines how the discourses of democratic elitism and meritocracy help allocate different citizen roles to students and define the nature of the social studies citizenship education programmes for different educational tracks. While the Singapore education system is not unique in its stratification of…

  14. Emerging Patterns of Service for Citizen Groups.

    Science.gov (United States)

    Durrance, Joan C.

    1979-01-01

    Focuses on the role that citizen groups--both grass roots and nationally affiliated--play in local communities, examines the history of these groups, describes their activities, presents research findings, and sketches library service trends in several communities. References are included. (FM)

  15. Citizen Satisfaction: Political Voice and Cognitive Biases

    DEFF Research Database (Denmark)

    Larsen, Morten Hjortskov

    Citizen satisfaction is increasingly being used as a measure of public service performance. It offers a performance measure that potentially encompasses many of the important attributes of the services that public managers would like to evaluate, some of which are not easily captured by other per...

  16. Racially Biased Policing: Determinants of Citizen Perceptions

    Science.gov (United States)

    Weitzer, Ronald; Tuch, Steven A.

    2005-01-01

    The current controversy surrounding racial profiling in America has focused renewed attention on the larger issue of racial bias by the police. Yet little is known about the extent of police racial bias and even less about public perceptions of the problem. This article analyzes recent national survey data on citizens' views of and reported…

  17. Exploring Sources of Punitiveness among German Citizens

    Science.gov (United States)

    Cochran, Joshua C.; Piquero, Alex R.

    2011-01-01

    Prior research examining punitive attitudes has typically focused on the United States and citizens' support for the death penalty or American "get-tough" criminal policies. Yet, little is known as to how punitive attitudes and their sources vary internationally. Using Germany as a case study, this article expands the scope of…

  18. Mass Incarceration and the Making of Citizens

    Science.gov (United States)

    Justice, Benjamin

    2014-01-01

    Like laws for formal education, laws for crime and punishment shape the relationship between the citizen and the state. They could, in fact, be equally powerful in building or breaking the civic spirit. In the past three decades, a revolution has occurred in the United States that is as insidious as it is unprecedented: the rise of the American…

  19. Galaxy Zoo: Motivations of Citizen Scientists

    Science.gov (United States)

    Raddick, M. Jordan; Bracey, Georgia; Gay, Pamela L.; Lintott, Chris J.; Cardamone, Carie; Murray, Phil; Schawinski, Kevin; Szalay, Alexander S.; Vandenberg, Jan

    2013-01-01

    Citizen science, in which volunteers work with professional scientists to conduct research, is expanding due to large online datasets. To plan projects, it is important to understand volunteers' motivations for participating. This paper analyzes results from an online survey of nearly 11000 volunteers in Galaxy Zoo, an astronomy citizen…

  20. Involving Citizens in Making Public Policy

    Science.gov (United States)

    Weeks, Silas B.

    1970-01-01

    Citizen participation in public policy making is a serious jeopardy because of the frustration cause by an enormous avalanche of information, by the impersonalization of our institutions, and by the technological revolution. A small social action committee dedicated to the collective interchange of ideas and information and working in an…

  1. Citizen Involvement in Public Library Planning.

    Science.gov (United States)

    Stephens, Annabel K.

    1991-01-01

    Discusses the planning process for public libraries developed by the Public Library Association (PLA) and describes two libraries' use of the planning process and the resulting benefits. Topics discussed include lay citizens as planning committee members; Friends of the Library; involvement of local government officials; and resultant increases in…

  2. Citizen Participation: A Manual of Techniques.

    Science.gov (United States)

    Newell, Charldean, Ed.

    Directed to the local government of smaller cities, this guide discusses five techniques for valid and feasible citizen participation. In each of the five selections the author describes the technique and indicates when its use is appropriate and what both its advantages and disadvantages are. The sections are arranged in order from the least to…

  3. Citizen participation in collaborative watershed partnerships.

    Science.gov (United States)

    Koehler, Brandi; Koontz, Tomas M

    2008-02-01

    Collaborative efforts are increasingly being used to address complex environmental problems, both in the United States and abroad. This is especially true in the growing field of collaborative watershed management, where diverse stakeholders work together to develop and advance water-quality goals. Active citizen participation is viewed as a key component, yet groups often struggle to attract and maintain citizen engagement. This study examined citizen participation behavior in collaborative watershed partnerships by way of a written survey administered to citizen members of 12 collaborative watershed groups in Ohio. Results for the determination of who joins such groups were consistent with the dominant-status model of participation because group members were not demographically representative of the broader community. The dominant-status model, however, does not explain which members are more likely to actively participate in group activities. Instead, individual characteristics, including political activity, knowledge, and comfort in sharing opinions with others, were positively correlated with active participation. In addition, group characteristics, including government-based membership, rural location, perceptions of open communication, perceptions that the group has enough technical support to accomplish its goals, and perceived homogeneity of participant opinions, were positively correlated with active participation. Overall, many group members did not actively participate in group activities.

  4. Citizen Science: Is It Worth Your Time?

    Science.gov (United States)

    Smith, Michael Chadwick

    2015-01-01

    This dissertation investigated citizen science, a tool that connects the public to the scientific community through research-based projects and education campaigns. Benefits include volunteers adding data to long-term data sets and improved scientific literacy among the public. Oftentimes, there is trepidation among scientists, managers, and…

  5. European Union News Themes in Romanian Radio Stations. Case Study: Europa FM and Radio Romania Actualitati

    Directory of Open Access Journals (Sweden)

    Antonia-Ioana Matei

    2013-05-01

    Full Text Available With Romania’s integration in the European Union, the media content related to the member states has acquired growing importance. The themes of journalism were enriched with new approaches towards national image in the European context and vice versa. At a first level, the study aims to conduct a quantitative analysis on the news topics broadcasted by Radio Romania Actualitati and Europa FM, for the duration of 32 days. The qualitative component focuses on the topics addressed in radio news in order to see what is the media content which reflects the image of the European Union. The findings show, beyond the numbers, that the editorial policy of the Romanian media is not concerned with the interests of the citizens - from the perspective of common themes - but rather with how can the EU, as a unified body, help member countries solve their problems.

  6. Commercial Radio as Communication.

    Science.gov (United States)

    Rothenbuhler, Eric W.

    1996-01-01

    Compares the day-to-day work routines of commercial radio with the principles of a theoretical communication model. Illuminates peculiarities of the conduct of communication by commercial radio. Discusses the application of theoretical models to the evaluation of practicing institutions. Offers assessments of commercial radio deriving from…

  7. Phosphorylation and gene expression of p53 are not affected in human cells exposed to 2.1425 GHz band CW or W-CDMA modulated radiation allocated to mobile radio base stations.

    Science.gov (United States)

    Hirose, H; Sakuma, N; Kaji, N; Suhara, T; Sekijima, M; Nojima, T; Miyakoshi, J

    2006-09-01

    A large-scale in vitro study focusing on low-level radiofrequency (RF) fields from mobile radio base stations employing the International Mobile Telecommunication 2000 (IMT-2000) cellular system was conducted to test the hypothesis that modulated RF fields induce apoptosis or other cellular stress response that activate p53 or the p53-signaling pathway. First, we evaluated the response of human cells to microwave exposure at a specific absorption rate (SAR) of 80 mW/kg, which corresponds to the limit of the average whole-body SAR for general public exposure defined as a basic restriction by the International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines. Second, we investigated whether continuous wave (CW) and wideband code division multiple access (W-CDMA) modulated signal RF fields at 2.1425 GHz induced apoptosis or any signs of stress. Human glioblastoma A172 cells were exposed to W-CDMA radiation at SARs of 80, 250, and 800 mW/kg, and CW radiation at 80 mW/kg for 24 or 48 h. Human IMR-90 fibroblasts from fetal lungs were exposed to both W-CDMA and CW radiation at a SAR of 80 mW/kg for 28 h. Under the RF field exposure conditions described above, no significant differences in the percentage of apoptotic cells were observed between the test groups exposed to RF signals and the sham-exposed negative controls, as evaluated by the Annexin V affinity assay. No significant differences in expression levels of phosphorylated p53 at serine 15 or total p53 were observed between the test groups and the negative controls by the bead-based multiplex assay. Moreover, microarray hybridization and real-time RT-PCR analysis showed no noticeable differences in gene expression of the subsequent downstream targets of p53 signaling involved in apoptosis between the test groups and the negative controls. Our results confirm that exposure to low-level RF signals up to 800 mW/kg does not induce p53-dependent apoptosis, DNA damage, or other stress response in human

  8. The Citizen Cyberscience Lectures - 1) Mobile phones and Africa: a success story 2) Citizen Problem Solving

    CERN Document Server

    CERN. Geneva; Bingham, Alpheus

    2009-01-01

    Dr. Alpheus Bingham, InnoCentive The Citizen Cyberscience Lectures are hosted by the partners of the Citizen Cyberscience Centre, CERN, The UN Institute of Training and Research and the University of Geneva. The goal of the Lectures is to provide an inspirational forum for participants from the various international organizations and academic institutions in Geneva to explore how information technology is enabling greater citizen participation in tackling global development challenges as well as global scientific research. The first Citizen Cyberscience Lectures will welcome two speakers who have both made major innovative contributions in this area. Dr. Mo Ibrahim, founder of Celtel International, one of Africa’s most successful mobile network operators, will talk about “Mobile phones and Africa: a success story”. Dr. Alpheus Bingham, founder of InnoCentive, a Web-based community that solves indus...

  9. Software Radio Sampling Rate Selection, Design and Synchronization

    CERN Document Server

    Venosa, Elettra; Palmieri, Francesco A N

    2012-01-01

    Software Radio represents the future of communication devices. By moving a radio's hardware functionalities into software, SWR promises to change the communication devices creating radios that, built on DSP based hardware platforms, are multiservice, multiband, reconfigurable and reprogrammable. This book describes the design of Software Radio (SWR). Rather than providing an overview of digital signal processing and communications, this book focuses on topics which are crucial in the design and development of a SWR, explaining them in a very simple, yet precise manner, giving simulation results that confirm the effectiveness of the proposed design.  Readers will gain in-depth knowledge of key issues so they can actually implement a SWR.  Specifically the book addresses the following issues: proper low-sampling rate selection in the multi-band received signal scenario, architecture design for both software radio receiver and transmitter devices and radio synchronization. Addresses very precisely the most imp...

  10. Governmentality and Religion in the Construction of the Argentinean Citizen

    Science.gov (United States)

    Caride, Ezequiel Gomez

    2013-01-01

    Numerous studies regarding citizens' identity and nation-building issues have relegated the analysis of religion, understood as a cultural practice, and its role in the governing of the citizen. However, this article states that religious narrative is still a crucial technology of government to conduct the conduct of citizens. Through the…

  11. The citizen as datasupplier in E-government

    DEFF Research Database (Denmark)

    Arleth, Mette; Schrøder, Anne Lise; Staunstrup, Jan K.

    2006-01-01

    This paper reports on an ongoing study of how to mobilise and utilize the citizen as data supplier in e-government. The role of the citizen is seen in the context of public participation, and a number of possible application areas for online tools where the citizen can serve the public administra...

  12. Citizen Participation and Citizenship Education in the 21st Century.

    Science.gov (United States)

    Langton, Stuart

    The belief in citizen participation, along with the values of liberty and equality, have shaped the U.S. character and are reflected in the nation's institutions and behavior. This participation is manifested by electoral participation, citizen action, citizen involvement, obligatory participation, volunteer service, and mutual self-help. To take…

  13. 24 CFR 570.441 - Citizen participation-insular areas.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 3 2010-04-01 2010-04-01 false Citizen participation-insular areas...-Entitlement CDBG Grants in Hawaii and Insular Areas Programs § 570.441 Citizen participation—insular areas. (a... shall comply with the citizen participation requirements described in this section. An insular...

  14. 36 CFR 72.46 - Citizen participation requirements.

    Science.gov (United States)

    2010-07-01

    ... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Citizen participation..., Rehabilitation and Innovation § 72.46 Citizen participation requirements. (a) Recovery Action Program Grants. Citizen participation is required for developing and implementing a Recovery Action Program (§ 72,...

  15. Ham radio for dummies

    CERN Document Server

    Silver, H Ward

    2013-01-01

    An ideal first step for learning about ham radio Beyond operating wirelessly, today's ham radio operators can transmit data and pictures; use the Internet, laser, and microwave transmitters; and travel to places high and low to make contact. This hands-on beginner guide reflects the operational and technical changes to amateur radio over the past decade and provides you with updated licensing requirements and information, changes in digital communication (such as the Internet, social media, and GPS), and how to use e-mail via radio. Addresses the critical use of ham radio for replacing downe

  16. Optically Faint Radio Sources: Reborn AGN?

    CERN Document Server

    Filho, Mercedes E; Lobo, Catarina; Antón, Sonia

    2011-01-01

    We have discovered a number of relatively strong radio sources in the field-of-view of SDSS galaxy clusters which present no optical counterparts down to the magnitude limits of the SDSS. The optically faint radio sources appear as double-lobed or core-jet objects on the FIRST radio images and have projected angular sizes ranging from 0.5 to 1.0 arcmin. We have followed-up these sources with near-infrared imaging using the wide-field imager HAWK-I on the VLT. K_s-band emitting regions, about 1.5 arcsec in size and coincident with the centers of the radio structures, were detected in all the sources, with magnitudes in the range 17-20 mag. We have used spectral modelling to characterize the sample sources. In general, the radio properties are similar to those observed in 3CRR sources but the optical-radio slopes are consistent with moderate to high redshift (z<4) gigahertz-peaked spectrum sources. Our results suggest that these unusual objects are galaxies whose black hole has been recently re-ignited but r...

  17. Radio Loud and Radio Quiet Quasars

    CERN Document Server

    Kellermann, K I; Kimball, A E; Perley, R A; Ivezic, Zeljko

    2016-01-01

    We discuss 6 GHz JVLA observations covering a volume-limited sample of 178 low redshift ($0.2 5 \\mathrm{~mJy~beam}^{-1}$ ($log(L) \\gtrsim 24$). The radio luminosity function of optically selected QSOs and the extended radio emission associated with RLQs are both inconsistent with simple "unified" models that invoke relativistic beaming from randomly oriented QSOs to explain the difference between RLQs and RQQs. Some intrinsic property of the AGNs or their host galaxies must also determine whether or not a QSO appears radio loud.

  18. Radiography of Spanish Radio

    Directory of Open Access Journals (Sweden)

    Dra. Emma Rodero Antón

    2007-01-01

    Full Text Available In its eighty years of existence, radio has been always characterized to adapt to the social, cultural and technological transformations. Thus it has been until this moment. Nevertheless, some years ago, the authors and professionals of this medium have been detecting a stagnation that affects to its structure. At a time in continuous technological evolution, radio demands a deep transformation. For that reason, from the conviction of which the future radio, public and commercial, will necessarily have to renew itself, in this paper we establish ten problems and their possible solutions to the radio crisis in order to draw an x-ray of radio in Spain. Radio has future, but it is necessary to work actively by it. That the radio continues being part of sound of our life, it will depend on the work of all: companies, advertisers, professionals, students, investigators and listeners.

  19. Science experiences of citizen scientists in entomology research

    Science.gov (United States)

    Lynch, Louise I.

    Citizen science is an increasingly popular collaboration between members of the public and the scientific community to pursue current research questions. In addition to providing researchers with much needed volunteer support, it is a unique and promising form of informal science education that can counter declining public science literacy, including attitudes towards and understanding of science. However, the impacts of citizen science programs on participants' science literacy remains elusive. The purpose of this study was to balance the top-down approach to citizen science research by exploring how adult citizen scientists participate in entomology research based on their perceptions and pioneer mixed methods research to investigate and explain the impacts of citizen science programs. Transference, in which citizen scientists transfer program impacts to people around them, was uncovered in a grounded theory study focused on adults in a collaborative bumble bee research program. Most of the citizen scientists involved in entomology research shared their science experiences and knowledge with people around them. In certain cases, expertise was attributed to the individual by others. Citizen scientists then have the opportunity to acquire the role of expert to those around them and influence knowledge, attitudinal and behavioral changes in others. An intervention explanatory sequential mixed methods design assessed how entomology-based contributory citizen science affects science self-efficacy, self-efficacy for environmental action, nature relatedness and attitude towards insects in adults. However, no statistically significant impacts were evident. A qualitative follow-up uncovered a discrepancy between statistically measured changes and perceived influences reported by citizen scientists. The results have important implications for understanding how citizen scientists learn, the role of citizen scientists in entomology research, the broader program impacts and

  20. Analisis Kendala Perizinan Spektrum Frekuensi Radio untuk Radio Komunitas

    OpenAIRE

    2014-01-01

    Izin penggunaan spektrum frekuensi radio diatur dalam Undang-undang No.36 tahun 1999 tentang Telekomunikasi. Saat ini masih ditemukan Radio Komunitas yang belum memiliki Izin Stasiun Radio (ISR). Penelitian ini bertujuan untuk menemu kenali kendala-kendala yang dihadapi Radio Komunitas pada proses pengajuan Izin Stasiun Radio (ISR). Teknik pengumpulan data melalui wawancara dengan penanggungjawab Radio Komunitas dan pejabat di lingkungan Balai Monitor Frekuensi Radio (Balmon) di Jakarta, Sema...

  1. EJSM Radar instruments: Natural radio noise from Jupiter

    Science.gov (United States)

    Cecconi, Baptiste; Hess, Sébastien; Zarka, Philippe; Blankenship, Donald; Bruzzone, Lorenzo; Santos-Costa, Daniel; Bougeret, Jean-Louis

    2010-05-01

    Radar instruments are part of the core payload of the Europa Jupiter System Mission (EJSM) spacecraft: NASA- led JEO (Jupiter Europa Orbiter) and ESA-led JGO (Jupiter Ganymede Orbiter). At this point of the project, several frequency bands are foreseen for radar studies between 5MHz and 50MHz. While the high frequencies (40 to 50 MHz) are clean bands since natural jovian radio emissions show a high frequency cutoff at about 40 MHz, lower frequencies are right in the middle of the intense decametric (DAM) radio emissions. We present a review of spectral intensity, variability and sources of these radio emissions. As the radio emission are beamed, it is possible to model the visibility of the radio emissions, as seen from the vicinity of Europa or Ganymede. We have investigated Io-related radio emissions as well as radio emissions related to the auroral oval. One result from these simulations is that some portion of the orbit of Europa is clean from Non-Io DAM emissions above 22 MHz. We also review the radiation belts synchrotron emission characteristics. This study clearly shows that a deep understanding of the natural radio emissions at Jupiter is necessary to prepare the future EJSM radar instrumentation.

  2. Factors influencing citizen participation in community management

    Directory of Open Access Journals (Sweden)

    Ali Shamai

    2015-04-01

    Full Text Available The primary objective of this study is to assess the factors affecting citizen participation in community management in district 13 of Tehran Municipality. Measured variables are: social cohesion, profitable partnerships, social-economic agencies, trust among civilians, trust in municipality management, feelings of powerlessness and social anomie. The results of the implementation of Pearson correlation test show that all of these variables had significant relationships with community participation in neighborhood management. The results of multiple regression analysis showed that three variables of social cohesion, profitable partnerships and socio-economic status had explained 37% of changes in citizen participation in community management while the changing social cohesion maintained the highest impact.

  3. Galaxy Zoo: Morphological Classification and Citizen Science

    OpenAIRE

    Fortson, Lucy; Masters, Karen; Nichol, Robert; Borne, Kirk; Edmondson, Edd; Lintott, Chris; Raddick, Jordan; Schawinski, Kevin; Wallin, John

    2011-01-01

    We provide a brief overview of the Galaxy Zoo and Zooniverse projects, including a short discussion of the history of, and motivation for, these projects as well as reviewing the science these innovative internet-based citizen science projects have produced so far. We briefly describe the method of applying en-masse human pattern recognition capabilities to complex data in data-intensive research. We also provide a discussion of the lessons learned from developing and running these community-...

  4. Using citizen science to monitor pollination services

    OpenAIRE

    Birkin, Linda; Goulson, Dave

    2015-01-01

    1. Pollination by insects is a vital ecosystem service and the need for its assessment is increasing in recognition and political pressure, but there are currently no large-scale systematic monitoring schemes in place to measure the direct provision of this service.\\ud 2. This study tested a protocol for using a citizen science approach to quantify pollination service provision in gardens and allotments, requiring participants to grow Vica faba L. plants and carry out some simple manipulation...

  5. Spectral Variability in Radio-Loud Quasars

    Indian Academy of Sciences (India)

    Minfeng Gu

    2014-09-01

    The spectral variability of a sample of 44 Flat-Spectrum Radio Quasars (FSRQs) and 18 Steep-Spectrum Radio Quasars (SSRQs) in SDSS stripe 82 region is investigated. Twenty-five of 44 FSRQs show a bluer-when-brighter trend (BWB), while only one FSRQ shows a redder-when-brighter trend, which is in contrast to our previous results. Eight of 18 SSRQs display a BWB. We found an anticorrelation between the Eddington ratio and the variability amplitude in the band for SSRQs, which is similar to that in radio-quiet AGNs. This implies that the thermal emission from the accretion disk may be responsible for the variability in SSRQs. The spectral variability from SDSS multi-epoch spectroscopy also shows BWB for several SSRQs, which is consistent with that from photometry.

  6. Gamma-Ray Bursts: A Radio Perspective

    Directory of Open Access Journals (Sweden)

    Poonam Chandra

    2016-01-01

    Full Text Available Gamma-ray bursts (GRBs are extremely energetic events at cosmological distances. They provide unique laboratory to investigate fundamental physical processes under extreme conditions. Due to extreme luminosities, GRBs are detectable at very high redshifts and potential tracers of cosmic star formation rate at early epoch. While the launch of Swift and Fermi has increased our understanding of GRBs tremendously, many new questions have opened up. Radio observations of GRBs uniquely probe the energetics and environments of the explosion. However, currently only 30% of the bursts are detected in radio bands. Radio observations with upcoming sensitive telescopes will potentially increase the sample size significantly and allow one to follow the individual bursts for a much longer duration and be able to answer some of the important issues related to true calorimetry, reverse shock emission, and environments around the massive stars exploding as GRBs in the early Universe.

  7. Senior radio listeners

    DEFF Research Database (Denmark)

    Blaakilde, Anne Leonora

    media platforms, not the least when listening to radio. The elder generation is no exception from this. Recently, for instance, the Danish public broadcast DR has carried out an exodus of programmes targeted for the senior segment. These programmes are removed from regular FM and sent to DAB receivers......Radiobroadcasting and the hardware materialization of radio have during the 20th century changed significantly, which means that senior radio listeners have travelled along with this evolution from large, impressive radio furnitures to DAB and small, wireless, mobile devices, and from grave...... and solemn radio voices to lightharted, laughing and chatting speakers. Senior radio listerners have experienced the development and refinements of technique, content and genres. It is now expected of all media users that they are capable of crossing media, combining, juggling and jumping between various...

  8. Interference measurements on amplitude compandored single sideband (ACSB) land mobil radio

    Science.gov (United States)

    Wootton, H.

    1983-06-01

    The National Telecommunications and Information Administration (NTIA) funded the ECAC to conduct adjacent-signal interference tests on a new radio system technology that shows promise of allowing smaller channel spacing in the Government land mobile radio band (162-174 MHz). The system tested was an amplitude compandored single-sideband radio (ACSB) manufactured by Sideband Technology, Inc. This report presents the adjacent-signal interference (ASI) result which will be employed by NTIA in evaluation of the potential usage of the ACSB technology in the Government land mobile radio band.

  9. Citizen Observatories: A Standards Based Architecture

    Science.gov (United States)

    Simonis, Ingo

    2015-04-01

    A number of large-scale research projects are currently under way exploring the various components of citizen observatories, e.g. CITI-SENSE (http://www.citi-sense.eu), Citclops (http://citclops.eu), COBWEB (http://cobwebproject.eu), OMNISCIENTIS (http://www.omniscientis.eu), and WeSenseIt (http://www.wesenseit.eu). Common to all projects is the motivation to develop a platform enabling effective participation by citizens in environmental projects, while considering important aspects such as security, privacy, long-term storage and availability, accessibility of raw and processed data and its proper integration into catalogues and international exchange and collaboration systems such as GEOSS or INSPIRE. This paper describes the software architecture implemented for setting up crowdsourcing campaigns using standardized components, interfaces, security features, and distribution capabilities. It illustrates the Citizen Observatory Toolkit, a software suite that allows defining crowdsourcing campaigns, to invite registered and unregistered participants to participate in crowdsourcing campaigns, and to analyze, process, and visualize raw and quality enhanced crowd sourcing data and derived products. The Citizen Observatory Toolkit is not a single software product. Instead, it is a framework of components that are built using internationally adopted standards wherever possible (e.g. OGC standards from Sensor Web Enablement, GeoPackage, and Web Mapping and Processing Services, as well as security and metadata/cataloguing standards), defines profiles of those standards where necessary (e.g. SWE O&M profile, SensorML profile), and implements design decisions based on the motivation to maximize interoperability and reusability of all components. The toolkit contains tools to set up, manage and maintain crowdsourcing campaigns, allows building on-demand apps optimized for the specific sampling focus, supports offline and online sampling modes using modern cell phones with

  10. Radio-loud high-redshift protogalaxy canidates in Bootes

    Energy Technology Data Exchange (ETDEWEB)

    Croft, S; van Breugel, W; Brown, M J; de Vries, W; Dey, A; Eisenhardt, P; Jannuzi, B; Rottgering, H; Stanford, S A; Stern, D; Willner, S P

    2007-07-20

    We used the Near Infrared Camera (NIRC) on Keck I to obtain K{sub s}-band images of four candidate high-redshift radio galaxies selected using optical and radio data in the NOAO Deep Wide-Field Survey in Bootes. Our targets have 1.4 GHz radio flux densities greater than 1 mJy, but are undetected in the optical. Spectral energy distribution fitting suggests that three of these objects are at z > 3, with radio luminosities near the FR-I/FR-II break. The other has photometric redshift z{sub phot} = 1.2, but may in fact be at higher redshift. Two of the four objects exhibit diffuse morphologies in K{sub s}-band, suggesting that they are still in the process of forming.

  11. Neptune's non-thermal radio emissions - Phenomenology and source locations

    Science.gov (United States)

    Rabl, Gerald K. F.; Ladreiter, H.-P.; Rucker, Helmut O.; Kaiser, Michael L.

    1992-01-01

    During the inbound and the outbound leg of Voyager 2's encounter with Neptune, the Planetary Radio Astronomy (PRA) experiment aboard the spacecraft detected short radio bursts at frequencies within the range of about 500-1300 kHz, and broad-banded smoothly varying emission patterns within the frequency range from about 40-800 kHz. Both emissions can be described in terms of a period of 16.1 hours determining Neptune's rotation period. Furthermore, just near closest approach, a narrow-banded smoothly varying radio component was observed occurring between 600 and 800 kHz. After giving a brief overview about some general characteristics of Neptune's nonthermal radio emission, the source locations of Neptune's emission components are determined, using an offset tilted dipole model for Neptune's magnetic field. Assuming that the emission originates near the electron gyrofrequency a geometrical beaming model is developed in order to fit the observed emission episodes.

  12. SPECTRUM AGGREGATION WITH OPTIMAL MULTI-BAND SCHEDULING

    DEFF Research Database (Denmark)

    Mihovska, Albena D.

    2010-01-01

    over two frequency bands (i.e., 2 GHz and 5 GHz) for a single operator scenario. The same type of Radio Access Technology (RAT) is considered for both frequency bands. It is assumed that the operator has gained access to a non-shared 2 GHz band and to part (or all) of the frequency pool band at 5 GHz....... The performance gain is analyzed in terms of higher data throughput. The performance is heavily dependent on the channel quality for each user in the considered bands which, in turn, is a function of the path loss and the distance from the Base Station (BS). The operator will have relevant improvements when...

  13. Transformations of Radio Aesthetics

    Directory of Open Access Journals (Sweden)

    Grażyna Stachyra

    2015-09-01

    Full Text Available The paper presents some remarks upon the nature of contemporary radio communications in the context of the terms “aesthetics” and “aesthetisation”. The latter, denoting a process of turning aesthetic phenomena into unaesthetic ones, becomes the dominant strategy of formatted radio. The “surface aesthetisation,” which provides mainly pleasure and entertainment, transcends the simple styling of objects or environment and appears to be a more significant strand of contemporary culture. The article shows several examples of “surface” modelling of radio programming and explains their purpose in radio communication.

  14. A Zynq-based Cluster Cognitive Radio

    OpenAIRE

    Rooks, Kurtis M.

    2014-01-01

    Traditional hardware radios provide very rigid solutions to radio problems. Intelligent software defined radios, also known as cognitive radios, provide flexibility and agility compared to hardware radio systems. Cognitive radios are well suited for radio applications in a changing radio frequency environment, such as dynamic spectrum access. In this thesis, a cognitive radio is demonstrated where the system self reconfigures to dem...

  15. DARIS : a low-frequency distributed aperture array for radio astronomy in space

    NARCIS (Netherlands)

    Boonstra, A.J.; Saks, N.; Falcke, H.; Klein-Wolt, M.; Bentum, M.J.; Rajan, R.T.; Wijnholds, M.; Arts, M.; Klooster, van 't K.; Beliën, F.

    2010-01-01

    The frequency band below 30 MHz is one of the last unexplored bands in radio astronomy. This band is well suited for studying the early cosmos at high hydrogen redshifts, the so-called dark ages, extragalactic surveys, (extra) solar planetary bursts, and high energy particle physics. In addition, sp

  16. A low-frequency distributed aperture array for radio astronomy in space

    NARCIS (Netherlands)

    Boonstra, A.J.; Saks, N.; Falcke, H.; Klein-Wolt, M.; Bentum, M.J.; Rajan, R.T.; Wijnholds, S.J.; Arts, M.; Klooster, van 't K.; Beliën, F.

    2010-01-01

    The frequency band below 30 MHz is one of the last unexplored bands in radio astronomy. This band is well suited for studying the early cosmos at high hydrogen redshifts, the so-called dark ages, extragalactic surveys, (extra) solar planetary bursts, and high energy particle physics. In addition, sp

  17. 47 CFR 90.315 - Special provisions governing use of frequencies in the 476-494 MHz band (TV Channels 15, 16, 17...

    Science.gov (United States)

    2010-10-01

    ... in the 476-494 MHz band (TV Channels 15, 16, 17) in the Southern Louisiana-Texas Offshore Zone. 90... RADIO SERVICES PRIVATE LAND MOBILE RADIO SERVICES Authorization in the Band 470-512 MHz (UHF-TV Sharing) § 90.315 Special provisions governing use of frequencies in the 476-494 MHz band (TV Channels 15,...

  18. A Survey on Dynamic Spectrum Access Techniques for Cognitive Radio

    CERN Document Server

    Garhwal, Anita

    2012-01-01

    Cognitive radio (CR) is a new paradigm that utilizes the available spectrum band. The key characteristic of CR system is to sense the electromagnetic environment to adapt their operation and dynamically vary its radio operating parameters. The technique of dynamically accessing the unused spectrum band is known as Dynamic Spectrum Access (DSA). The dynamic spectrum access technology helps to minimize unused spectrum bands. In this paper, main functions of Cognitive Radio (CR) i.e. spectrum sensing, spectrum management, spectrum mobility and spectrum sharing are discussed. Then DSA models are discussed along with different methods of DSA such as Command and Control, Exclusive-Use, Shared Use of Primary Licensed User and Commons method. Game-theoretic approach using Bertrand game model, Markovian Queuing Model for spectrum allocation in centralized architecture and Fuzzy logic based method are also discussed and result are shown.

  19. Open data for citizens: empowering citizens to make meaningful use of open data

    DEFF Research Database (Denmark)

    Götzen, Amalia De; Morelli, Nicola

    2016-01-01

    A large quantity of open data is now available to institutions, business and citizens. The potential of such new resource, though, has not been explored yet, also because of a lack of perspectives and scenarios on how open data can be used. The workshop aims at broadening the perspectives...... on the use of open data by investigating new scenarios for a wide use of open data, where citizens without any IT skills can be involved in a co-design session with the relevant stakeholders....

  20. Radio occultation measurements of the lunar ionosphere.

    Science.gov (United States)

    Pluchino, S.; Schillirò, F.; Salerno, E.; Pupillo, G.; Maccaferri, G.; Cassaro, P.

    Radio occultation measurements by using interplanetary probes is a well known technique to obtain information on planetary atmospheres. To further understand the morphology of the lunar ionosphere we performed radio occultation experiments by using the radio sounding technique. This method mainly consists in the analisys of the effects produced on the radio wave transmitted from the spacecraft to the Earth when it crosses the atmosphere. The wave amplitude and phase undergo modifications that are correlated to the physical parameters - i.e. electron density - of the crossed medium. The first data set was obtained during the lunar occultations of the European probe SMART-1 shortly before impacting the lunar soil on September 3rd, 2006. During this experiment several radio occultation measurements of the signal transmitted by the spacecraft were performed in S and X band by using the 32 meters radiotelescopes (at Medicina and Noto) of the Istituto di Radioastronomia - Istituto Nazionale di Astrofisica. Further experiments were performed during lunar occultations of Saturn and Venus. On May 22nd and June 18th 2007 the Cassini spacecraft, orbiting Saturn, and the Venus Express spacecraft, orbiting Venus, respectively were occulted by the Moon. The variation of the Total Electron Content (TEC) measured by our instruments (˜ 1013 el/m2) on this occasion is in agreement with values of the electron number density acquired by in situ measuments of the US Apollo missions and the USSR Luna 19 and 22 probes.

  1. Enhancing GNU Radio for Hardware Accelerated Radio Design

    OpenAIRE

    Irick, Charles Robert

    2010-01-01

    As technology evolves and new methods for designing radios arise, it becomes necessary to continue the search for fast and flexible development environments. Some of these new technologies include software defined radio (SDR), Field Programmable Gate Arrays (FPGAs), and the open source project GNU Radio. Software defined radio is a concept that GNU Radio has harnessed to allow developers to quickly create flexible radio designs. In terms of hardware, the maturity of FPGAs give ...

  2. Signal Processing Techniques Applied in RFI Mitigation of Radio Astronomy

    Directory of Open Access Journals (Sweden)

    Sixiu Wang

    2012-08-01

    Full Text Available Radio broadcast and telecommunications are present at different power levels everywhere on Earth. Radio Frequency Interference (RFI substantially limits the sensitivity of existing radio telescopes in several frequency bands and may prove to be an even greater obstacle for next generation of telescopes (or arrays to overcome. A variety of RFI detection and mitigation techniques have been developed in recent years. This study describes various signal process methods of RFI mitigation in radio astronomy, choose the method of Time-frequency domain cancellation to eliminate certain interference and effectively improve the signal to noise ratio in pulsar observations. Finally, RFI mitigation researches and implements in China radio astronomy will be also presented.

  3. CENSORS: A Combined EIS-NVSS Survey Of Radio Sources. I. Sample definition, radio data and optical identifications

    CERN Document Server

    Best, P N; Röttgering, H J A; Rengelink, R B; Brookes, M H; Wall, J

    2003-01-01

    A new sample of radio sources, with the designated name CENSORS (A Combined EIS-NVSS Survey Of Radio Sources), has been defined by combining the NRAO VLA Sky Survey (NVSS) at 1.4 GHz with the ESO Imaging Survey (EIS) Patch D, a 3 by 2 degree region of sky centred at 09 51 36.0, -21 00 00 (J2000). New radio observations of 199 NVSS radio sources with NVSS flux densities S(1.4GHz) > 7.8mJy are presented, and compared with the EIS I-band imaging observations which reach a depth of I~23; optical identifications are obtained for over two-thirds of the ~150 confirmed radio sources within the EIS field. The radio sources have a median linear size of 6 arcseconds, consistent with the trend for lower flux density radio sources to be less extended. Other radio source properties, such as the lobe flux density ratios, are consistent with those of brighter radio source samples. From the optical information, 30-40% of the sources are expected to lie at redshifts z >~ 1.5. One of the key goals of this survey is to accuratel...

  4. Analisis Kendala Perizinan Spektrum Frekuensi Radio untuk Radio Komunitas

    Directory of Open Access Journals (Sweden)

    Sri Wahyuningsih

    2014-03-01

    Full Text Available Izin penggunaan spektrum frekuensi radio diatur dalam Undang-undang No.36 tahun 1999 tentang Telekomunikasi. Saat ini masih ditemukan Radio Komunitas yang belum memiliki Izin Stasiun Radio (ISR. Penelitian ini bertujuan untuk menemu kenali kendala-kendala yang dihadapi Radio Komunitas pada proses pengajuan Izin Stasiun Radio (ISR. Teknik pengumpulan data melalui wawancara dengan penanggungjawab Radio Komunitas dan pejabat di lingkungan Balai Monitor Frekuensi Radio (Balmon di Jakarta, Semarang dan Yogyakarta. Analisis data mengacu pada model Matthew B Miles dan A Michael Huberman. Hasil penelitian menyatakan kendala yang dihadapi terutama pada sertifikasi perangkat Radio Komunitas.

  5. Valuing commercial radio licences

    NARCIS (Netherlands)

    Kerste, M.; Poort, J.; van Eijk, N.

    2015-01-01

    Within the EU regulatory framework, licensees for commercial radio broadcasting may be charged a fee to ensure optimal allocation of scarce resources but not to maximize public revenues. While radio licence renewal occurs in many EU countries, an objective, model-based approach for setting licence f

  6. Radio Graceful Hamming Graphs

    Directory of Open Access Journals (Sweden)

    Niedzialomski Amanda

    2016-11-01

    Full Text Available For k ∈ ℤ+ and G a simple, connected graph, a k-radio labeling f : V (G → ℤ+ of G requires all pairs of distinct vertices u and v to satisfy |f(u − f(v| ≥ k + 1 − d(u, v. We consider k-radio labelings of G when k = diam(G. In this setting, f is injective; if f is also surjective onto {1, 2, . . . , |V (G|}, then f is a consecutive radio labeling. Graphs that can be labeled with such a labeling are called radio graceful. In this paper, we give two results on the existence of radio graceful Hamming graphs. The main result shows that the Cartesian product of t copies of a complete graph is radio graceful for certain t. Graphs of this form provide infinitely many examples of radio graceful graphs of arbitrary diameter. We also show that these graphs are not radio graceful for large t.

  7. Radio Emission from Exoplanets

    OpenAIRE

    George, Samuel J.; Stevens, Ian R.

    2008-01-01

    We present results from new low frequency observations of two extrasolar planetary systems (Epsilon Eridani and HD128311) taken at 150 MHz with the Giant Metrewave Radio Telescope (GMRT). We do not detect either system, but are able to place tight upper limits on their low frequency radio emission.

  8. Unlocking radio broadcasts

    DEFF Research Database (Denmark)

    Skov, Mette; Lykke, Marianne

    2012-01-01

    This poster reports the preliminary results of a user study uncovering the information seeking behaviour of humanities scholars dedicated to radio research. The study is part of an interdisciplinary research project on radio culture and auditory resources. The purpose of the study is to inform th...

  9. Community and alternative media in the citizen´s protest cycle since the 15M-movement

    Directory of Open Access Journals (Sweden)

    Alejandro Barranquero Carretero

    2015-03-01

    Full Text Available The current economical and institutional crisis of journalism in Spain has contributed to the revitalization of media and communicational experiences of social movements and non-profit organizations. This revival of citizen participation reaches prominence from the 15M movement in May 2011, which has contributed to the strengthening of networks among the Third Sector of Media, as well as to the first large-scale coordinated broadcasts by community radios in Spain. This article aims at describing the physiognomy of an emerging sector at the margins of public and private-commercial media. Methodology combines observation and documentary research along with structured in-depth interviews to coordinators and citizen reporters of these media coverages.

  10. Rehousing homeless citizens with assertive community treatment

    DEFF Research Database (Denmark)

    Benjaminsen, Lars

    This report presents the results of a study of an ACT-programme (Assertive Community Treatment) in Copenhagen, Denmark, which has been part of the Danish national homelessness strategy. The ACT-programme is aimed at rehousing homeless individuals and providing floating support in the citizens own...... professionals including a psychiatrist, a nurse, an addiction councilor, and social workers with administrative authority from the social office and the job center. In the international research literature ACT has been shown in randomized controlled trials to be a very effective method in bringing individuals...

  11. Crowdsourcing the human gut:Is crowdsourcing also 'citizen science'?

    OpenAIRE

    Del Savio, Lorenzo; Prainsack, Barbara; Buyx, Alena

    2016-01-01

    The participation of non-professionally trained people in so-called citizen science (CS) projects is a much discussed topic at the moment. Frequently, however, the contribution of citizens is limited to only a few narrow tasks. Focusing on an initiative dedicated to the study of the human microbiome, this paper describes such a case where citizen participation is limited to the provision of funding, samples, and personal data. Researchers opted for a crowdsourced approaches because other form...

  12. Catholic citizen education :el salvador 1832-1880

    OpenAIRE

    González Torres, Julián

    2013-01-01

    In this paper, the author analyzes the way in which the Salvadoran State, during the years 1832 to 1880, intended to shape a kind of Catholic citizen, starting from elementary school. The research shows that such system educated the children (future citizens) for eternal life (celestial) instead of training them for the tasks of the State. Nevertheless, the Salvadoran State (at least until 1880) saw in the Catholic religion the most suitable form to shape the citizens that the fatherland dema...

  13. Uncertainty in Citizen Science observations: from measurement to user perception

    Science.gov (United States)

    Lahoz, William; Schneider, Philipp; Castell, Nuria

    2016-04-01

    Citizen Science activities concern general public engagement in scientific research activities when citizens actively contribute to science either with their intellectual effort or surrounding knowledge or with their tools and resources. The advent of technologies such as the Internet and smartphones, and the growth in their usage, has significantly increased the potential benefits from Citizen Science activities. Citizen Science observations from low-cost sensors, smartphones and Citizen Observatories, provide a novel and recent development in platforms for observing the Earth System, with the opportunity to extend the range of observational platforms available to society to spatio-temporal scales (10-100s m; 1 hr or less) highly relevant to citizen needs. The potential value of Citizen Science is high, with applications in science, education, social aspects, and policy aspects, but this potential, particularly for citizens and policymakers, remains largely untapped. Key areas where Citizen Science data start to have demonstrable benefits include GEOSS Societal Benefit Areas such as Health and Weather. Citizen Science observations have many challenges, including simulation of smaller spatial scales, noisy data, combination with traditional observational methods (satellite and in situ data), and assessment, representation and visualization of uncertainty. Within these challenges, that of the assessment and representation of uncertainty and its communication to users is fundamental, as it provides qualitative and/or quantitative information that influences the belief users will have in environmental information. This presentation will discuss the challenges in assessment and representation of uncertainty in Citizen Science observations, its communication to users, including the use of visualization, and the perception of this uncertainty information by users of Citizen Science observations.

  14. Logistics and logistics support in crisis management and citizen protection

    OpenAIRE

    HOLEJŠOVSKÝ, Jan

    2010-01-01

    ABSTRAKT LOGISTICS AND LOGISTICS SUPPORT IN CRISIS MANAGEMENT AND CITIZEN PROTECTION The graduation thesis on topic ``Logistics and logistics support in crisis management and citizen protection" is divided into several chapters, which in summary are a material presenting information about logistics and logistics support in crisis management and citizen protection. This was one of the aims at this work. Chapters I., II., III., IV. describe logistics and logistics support, crisis management, ci...

  15. CULTURAL ADAPTATION OF CZECH CITIZENS IN THE REPUBLIC OF TURKEY

    Directory of Open Access Journals (Sweden)

    Jiří Čeněk

    2016-09-01

    Full Text Available This article relates to the process of adaptation of Czech citizens to Turkish culture. The article explores the perception of Turkish culture by Czech citizens, problems they encounter in the Turkish society and the ways of their adjustment to the host culture. The empirical research on 10 Czech citizens was conducted using the method of semi-structured interviews. The article addresses the most important issues connected with the process of cultural adaptation.

  16. Citizen participation in planning decisions of public authorities

    DEFF Research Database (Denmark)

    The report is the Danish contribution to an EEC-study on the citizen participation in planning decisions of public authorities. In the other EEC-countries similar reports have been done. The report describes the rules on citizen participation, that are stated by laws. Different aspects of citizen...... participation are analysed, f.ex. the forms and the time-limitations in the participation....

  17. Schools/Citizen Science: A Response to "The Future of Citizen Science"

    Science.gov (United States)

    Weinstein, Matthew

    2012-01-01

    This paper builds on Mueller, Tippins, and Bryan's paper to ask how neoliberal restructuring impacts the form of appropriate and possible democratic science/education. It examines the compatibilities between antidemocratic tendencies of current schooling and common forms citizen science. It also clarifies several details regarding the street-medic…

  18. Fictional citizens and real effects: accountability to citizens in competitive and monopolistic markets

    NARCIS (Netherlands)

    Meijer, A.J.; Schillemans, T.

    2009-01-01

    This paper evaluates the influence of market conditions – (semi) competitive versus monopolistic markets –on (the effects of) citizen accountability on public sector organisations. Empirical material from case studies in education, healthcare, social security and land registry in the Netherlands is

  19. HYBASE : HYperspectral BAnd SElection

    NARCIS (Netherlands)

    Schwering, P.B.W.; Bekman, H.H.P.T.; Seijen, H.H. van

    2009-01-01

    Band selection is essential in the design of multispectral sensor systems. This paper describes the TNO hyperspectral band selection tool HYBASE. It calculates the optimum band positions given the number of bands and the width of the spectral bands. HYBASE is used to assess the minimum number of spe

  20. The Open Format and Citizen Participation in Transportation Planning

    DEFF Research Database (Denmark)

    Flyvbjerg, Bent

    1984-01-01

    Recent developments in transportation planning and policy indicate that citizen participation and openness may receive less emphasis in the future in favor of more closed methods of decision making and control. Have the merits and drawbacks of citizen participation and openness changed significan......Recent developments in transportation planning and policy indicate that citizen participation and openness may receive less emphasis in the future in favor of more closed methods of decision making and control. Have the merits and drawbacks of citizen participation and openness changed...... with the trend for considering social, environmental, and ethical issues in transportation planning and policy....

  1. Citizen Science: Probing the Virtues and Contexts of Participatory Research

    Directory of Open Access Journals (Sweden)

    Aya H. Kimura

    2016-12-01

    Full Text Available Citizen science is an increasingly popular activity, from bird counts to amateur water sample collection to air quality monitoring. Researchers and theorists in the field of science and technology studies (STS have typically applauded these efforts because they make science more participatory, providing an example of the democratization of science, or, at least, more equitable engagement between experts and the lay public. However, a broader review of the literature on citizen science suggests that participation is but one of many virtues that practitioners and observers find in the practices of citizen science. This literature review makes two interventions. First, we discuss the dimensions of citizen science that do not easily fit in a typology or spectrum of participatory practices. We identify seven different virtues claimed of citizen science: increasing scientific data; increasing citizens' scientific literacy and awareness; building community capacity for environmental protection; building more equal relationship between scientists and citizens; filling knowledge gaps and challenging official accounts; driving policy change; and catching polluters. Second, we consider the social and political contexts that often create contradictory situations or dilemmas for citizen scientists. Going forward, a robust framework for the analysis of citizen science would not only address the ways scientific data is collected and put to a particular use, but also situate the project in relation to broader structural forces of scientization, neocolonialism, globalization, and neoliberalization.

  2. Informed citizen and empowered citizen in health: results from an European survey

    Directory of Open Access Journals (Sweden)

    Prokosch Hans-Ulrich

    2011-04-01

    Full Text Available Abstract Background The knowledge about the relationship between health-related activities on the Internet (i.e. informed citizens and individuals' control over their own experiences of health or illness (i.e. empowered citizens is valuable but scarce. In this paper, we investigate the correlation between four ways of using the Internet for information on health or illness and citizens attitudes and behaviours toward health professionals and health systems and establish the profile of empowered eHealth citizens in Europe. Methods Data was collected during April and May 2007 (N = 7022, through computer-assisted telephone interviews (CATI. Respondents from Denmark, Germany, Greece, Latvia, Norway, Poland and Portugal participated in the survey. The profiles were generated using logistic regressions and are based on: a socio-demographic and health information, b the level of use of health-related online services, c the level of use of the Internet to get health information to decide whether to consult a health professional, prepare for a medical appointment and assess its outcome, and d the impact of online health information on citizens' attitudes and behavior towards health professionals and health systems. Results Citizens using the Internet to decide whether to consult a health professional or to get a second opinion are likely to be frequent visitors of health sites, active participants of online health forums and recurrent buyers of medicines and other health related products online, while only infrequent epatients, visiting doctors they have never met face-to-face. Participation in online health communities seems to be related with more inquisitive and autonomous patients. Conclusions The profiles of empowered eHealth citizens in Europe are situational and country dependent. The number of Europeans using the Internet to get health information to help them deal with a consultation is raising and having access to online health information

  3. The Late Radio Spectrum of SN1993J

    CERN Document Server

    Pérez-Torres, M A; Marcaide, J M

    2002-01-01

    We present VLA radio continuum measurements of SN1993J in M81 at the frequencies of 0.32 (P-band), 1.3 and 1.7 (L-band), 4.9 (C-band), 8.5 (X-band), and 14.9 (U-band) GHz carried out on December 17 and 21, 2000, about 2820 days after the supernova explosion. We find that a power-law spectrum, free-free absorbed by an homogeneous --or clumpy, but not a mixture of both-- distribution of ionized gas, yields the best fit to the radio data. This result contrasts with the modeling of the early ($t \\lessim $230 days) radio emission from SN1993J, where a mixture of homogeneous and clumpy absorbers appeared to be necessary to adequately describe the behavior of the light curves, and thus gives support to the suggestion that a change in the mass-loss properties of the progenitor star took place in the last stages of its evolution. The radio spectrum of supernova SN1993J between 0.32 and 14.9 GHz is well characterized by $\\alpha = -0.67 \\pm 0.02 $ ($S_\

  4. Radio frequency path characterization for wide band quadrature amplitude modulation

    Energy Technology Data Exchange (ETDEWEB)

    Bracht, R.

    1998-12-31

    Remote, high speed, high explosive wave front monitoring requires very high bandwidth telemetry to allow transmission of diagnostic data before the explosion destroys the sensor system itself. The main motivation for this study is that no known existing implementation of this sort has been applied to realistic weapons environments. These facts have prompted the research and gathering of data that can be used to extrapolate towards finding the best modulation method for this application. In addition to research of similar existing analysis and testing operations, data was recently captured from a Joint Test Assembly (JTA) Air Launched Cruise Missile (ALCM) flight.

  5. The formation of citizens: the pediatrician's role

    Directory of Open Access Journals (Sweden)

    Dioclécio Campos Júnior

    2016-06-01

    Full Text Available ABSTRACT Objective: This review article aims to define the fundamental role of the pediatrician in the formation of citizens in the 21st century. Source of data: Significant bibliographical contributions produced by neuroscience, ecology, and epigenetics in the early childhood scenario. Synthesis of data: Many diseases that impair the lives of adults result from severe and often uncontrollable disorders that occur in early childhood, an irreplaceable period for the safe construction of the human brain, personality, and intelligence. There is noteworthy scientific evidence that has become unquestionable, according to which abuse and neglect and other forms of violence to which children are exposed during the the course of their lives, are the genesis of many physical ailments and other mental diseases, including depressive morbidity and schizophrenia. Conversely, it is also emphasized that healthy practices such as reading and listening to/playing music are able to intensively contribute to the exercise of cognitive capacity inherent to this period of life, as a prerequisite for the acquisition of learning indispensable to the high educational performance during the schooling period. Conclusion: In the light of the disclosed scientific evidence, the pediatrician emerges as the most differentiated professional to provide preventive and curative care indispensable to the skilled formation of a healthy citizen.

  6. Conceptual Surveys for Zooniverse Citizen Science Projects

    Science.gov (United States)

    Cormier, Sebastien; Prather, E. E.; Brissenden, G.; Lintott, C.; Gay, P. L.; Raddick, J.; Collaboration of Astronomy Teaching Scholars CATS

    2012-01-01

    The Citizen Science projects developed by Zooniverse allow volunteers to contribute to scientific research in a meaningful way by working with actual scientific data. In the Moon Zoo Citizen Science project volunteers classify geomorphological features in images from NASA's Lunar Reconnaissance Orbiter, and in the Galaxy Zoo project volunteers classify galaxies from SDSS-III and Hubble images. We created two surveys, the Lunar Cratering Concept Inventory (LCCI), and the Zooniverse Astronomy Concept Inventory (ZACS) to measure the impact that participation in Moon Zoo has on user conceptual knowledge. We describe how the survey was developed and validated in collaboration with education researchers and astronomers. The instrument was administered to measure changes to user conceptual knowledge as they gain experience with Moon Zoo. We discuss preliminary data analysis and how these results were used to change implementation of the survey to improve results. This material is based in part upon work supported by the National Science Foundation under Grant No. 0715517, a CCLI Phase III Grant for the Collaboration of Astronomy Teaching Scholars (CATS). Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the National Science Foundation.

  7. Radio source evolution

    CERN Document Server

    Perucho, Manel

    2015-01-01

    Baldwin (1982) wrote that "the distribution of sources in the radio luminosity, P, overall physical size, D, diagram" could be considered as "the radio astronomer's H-R diagram". However, unlike the case of stars, not only the intrinsic properties of the jets, but also those of the host galaxy and the intergalactic medium are relevant to explain the evolutionary tracks of radio radio sources. In this contribution I review the current status of our understanding of the evolution of radio sources from a theoretical and numerical perspective, using the P-D diagram as a framework. An excess of compact (linear size < 10 kpc) sources could be explained by low-power jets being decelerated within the host galaxy, as shown by recent numerical simulations. These decelerated jets could also explain the population of the radio sources that have been recently classified as FR0. I will discuss the possible tracks that radio sources may follow within this diagram, and some of the physical processes that can explain the d...

  8. Radio broadcasting via satellite

    Science.gov (United States)

    Helm, Neil R.; Pritchard, Wilbur L.

    1990-10-01

    Market areas offering potential for future narrowband broadcast satellites are examined, including international public diplomacy, government- and advertising-supported, and business-application usages. Technical issues such as frequency allocation, spacecraft types, transmission parameters, and radio receiver characteristics are outlined. Service and system requirements, advertising revenue, and business communications services are among the economic issues discussed. The institutional framework required to provide an operational radio broadcast service is studied, and new initiatives in direct broadcast audio radio systems, encompassing studies, tests, in-orbit demonstrations of, and proposals for national and international commercial broadcast services are considered.

  9. Ionosphere and Radio Communication

    Indian Academy of Sciences (India)

    Saradi Bora

    2017-02-01

    The Earth's ionosphere consists of plasma produced by thephotoionization of thin upper atmospheric gases by UV raysand photons of short wavelength from the sun. The upperionosphere is used for radio communication and navigationas it reflects long, medium, as well as short radio waves. Sincesolar radiation is the main cause of the existence of ionosphere,any variation in the radiations can affect the entireradio communication system. This article attempts to brieflyintroduce the readers to the study of ionosphere in the contextof its use as a radio reflector, with particular reference toIndia.

  10. Unlocking radio broadcasts

    DEFF Research Database (Denmark)

    Lykke, Marianne; Skov, Mette

    2012-01-01

    This poster reports the preliminary results of a user study uncovering the information seeking behaviour of humanities scholars dedicated to radio research. The study is part of an interdisciplinary research project on radio culture and auditory resources. The purpose of the study is to inform...... the design of information architecture and interaction design of a research infrastructure that will enable future radio and audio based research. Results from a questionnaire survey on humanities scholars’ research interest and information needs, preferred access points, and indexing levels are reported...

  11. Radio y elecciones

    Directory of Open Access Journals (Sweden)

    Alma Rosa Alva de la Selva

    2000-01-01

    Full Text Available En este trabajo se analiza el comportamiento de la radio en México ante la contienda electoral de julio de 2000. Se examina el papel de la radio como espacio para la discusión política, así como el tratamiento informativo que hizo del tema. Asimismo, se analiza la posible repercusión de factores de reciente surgimiento en el panorama radiofónico para un manejo más autónomo de la información política en la radio

  12. Software-defined radio with flexible RF front end for satellite maritime radio applications

    Science.gov (United States)

    Budroweit, Jan

    2016-09-01

    This paper presents the concept of a software-defined radio with a flexible RF front end. The design and architecture of this system, as well as possible application examples will be explained. One specific scenario is the operation in maritime frequency bands. A well-known service is the Automatic Identification System (AIS), which has been captured by the DLR mission AISat, and will be chosen as a maritime application example. The results of an embedded solution for AIS on the SDR platform are presented in this paper. Since there is an increasing request for more performance on maritime radio bands, services like AIS will be enhanced by the International Association of Marine Aids to Navigation and Lighthouse Authorities (IALA). The new VHF Data Exchange Service (VDES) shall implement a dedicated satellite link. This paper describes that the SDR with a flexible RF front end can be used as a technology demonstration platform for this upcoming data exchange service.

  13. Smart radio: spectrum access for first responders

    Science.gov (United States)

    Silvius, Mark D.; Ge, Feng; Young, Alex; MacKenzie, Allen B.; Bostian, Charles W.

    2008-04-01

    This paper details the Wireless at Virginia Tech Center for Wireless Telecommunications' (CWT) design and implementation of its Smart Radio (SR) communication platform. The CWT SR can identify available spectrum within a pre-defined band, rendezvous with an intended receiver, and transmit voice and data using a selected quality of service (QoS). This system builds upon previous cognitive technologies developed by CWT for the public safety community, with the goal of providing a prototype mobile communications package for military and public safety First Responders. A master control (MC) enables spectrum awareness by characterizing the radio environment with a power spectrum sensor and an innovative signal detection and classification module. The MC also enables spectrum and signal memory by storing sensor results in a knowledge database. By utilizing a family radio service (FRS) waveform database, the CWT SR can create a new communication link on any designated FRS channel frequency using FM, BPSK, QPSK, or 8PSK modulations. With FM, it supports analog voice communications with legacy hand-held FRS radios. With digital modulations, it supports IP data services, including a CWT developed CVSD-based VoIP protocol. The CWT SR coordinates spectrum sharing between analog primary users and digital secondary users by applying a simple but effective channel-change protocol. It also demonstrates a novel rendezvous protocol to facilitate the detection and initialization of communications links with neighboring SR nodes through the transmission of frequency-hopped rendezvous beacons. By leveraging the GNU Radio toolkit, writing key modules entirely in Python, and utilizing the USRP hardware front-end, the CWT SR provides a dynamic spectrum test bed for future smart and cognitive radio research.

  14. Band-monitoring Payload for a CubeSat Satellite

    Directory of Open Access Journals (Sweden)

    P. Vagner

    2012-04-01

    Full Text Available During changing sun activity, the ionosphere is responding accordingly and therefore it is interesting to observe the propagation behavior of shortwave bands. For the above mentioned purpose we have designed a band-monitoring payload for an experimental CubeSat satellite. The payload consists of a receiver, which is able to receive SSB modulated narrowband signals in 28 MHz uplink band, and a transmitter with FM modulation in UHF downlink band. The receiver frequency is selected to be at the center of radio amateur activity with low data rate digital modulations.

  15. Energy in Solid Waste: A Citizen Guide to Saving.

    Science.gov (United States)

    Citizens Advisory Committee on Environmental Quality.

    This booklet contains information for citizens on solid wastes. It discusses the possible energy available in combustible and noncombustible trash. It suggests how citizens can reduce waste at home through discriminating buying practices and through recycling and reuse of resources. Recommendations are given for community action along with state…

  16. Developing the European Citizen: Investing in Europe's Democratic Future

    Science.gov (United States)

    Dziuban, Charles D.; Cornett, Jeffery W.; Pitts, Annette Boyd; Setenyi, Janos; Gal, Tibor; Eich, Laszlo

    2007-01-01

    Recognizing that democracy is not a static concept and that it should be learned and lived on a daily basis, the Council of Europe has named 2005 the European Year of Citizenship through Education. Citizens of European Union (EU) member countries face new challenges in their participation as citizens in a democratic society. While EU citizenship…

  17. Citizen science: integrating scientific research, ecological conservation and public participation

    Directory of Open Access Journals (Sweden)

    Jian Zhang

    2013-11-01

    Full Text Available Citizen science, also known as “public participation in scientific research”, is defined as scientific activities in which non-professional scientists participate as volunteers in data collection, analysis and dissemination within a scientific project. With the advent of the information age, citizen science projects, especially in ecological conservation and environmental monitoring, are rapidly expanding our knowledge of the world around us, and contributing to management and policy decisions. Citizen science projects can be classified into five types of models: contractual, contributory, collaborative, co-created and collegial projects. In China, public participation in science related activities has had a long history, but current contributions in citizen science are limited because of relatively low public participation, and the weaknesses in data quality control, data management and analysis. Recently, citizen science has been applied to bird watching and plant monitoring, with some positive and negative experiences. To better increase citizen science activities and enhance such contributions to academic research, improvements are urgently required in financial support, the development of project platforms, the application of new technology, and international collaboration. We believe that the enhancement of citizen science will greatly promote the development of ecological conservation, environmental monitoring and related research fields. To help with this we have established a platform for China citizen science projects (http://www.gongzhongkexue.org to promote communication and cooperation among scientists, governments, other organizations and the public.

  18. Influencing citizen behavior: Experiences from multichannel marketing pilot projects

    NARCIS (Netherlands)

    Wijngaert, van de Lidwien; Pieterson, Willem; Teerling, Marije L.

    2011-01-01

    Information technology allows national and local governments to satisfy the needs of citizens in a cost effective way. Unfortunately, citizens still tend to prefer traditional, more costly channels, such as the front desk, phone and mail. Through pilot projects government agencies attempt to influen

  19. An Evaluation of Citizen Participation in an Urban School.

    Science.gov (United States)

    Zelman, Susan; Grainer, Marc

    The operations of a citizen committee associated with two neighborhood public schools in the Boston area were studied to evaluate empirically the effectiveness of the committee in achieving certain policy goals. A case study approach to citizen committee power to influence educational decisionmaking was made in the areas of finance, curriculum,…

  20. How To Get Full Value from Citizen Committees.

    Science.gov (United States)

    McClellan, Carole Keeton

    To get full value from citizen advisory committees, school boards may use the following suggestions and guidelines. Be sure a lay citizen committee is needed before appointing one; provide specific responsibilities and duties; appoint the members to achieve balance according to sex, race, philosophy, and geography; use rotating terms; appoint the…

  1. Citizen Participation in School Affairs in Two Southern Cities.

    Science.gov (United States)

    Roaden, Arliss L.

    The effectiveness of organizations for citizen participation in school affairs depends on their influence in effecting school policies and decisions, and on their stability for sustained influence. In Atlanta, neither citizen initiated (Southern Leadership Conference) nor school initiated (Committee of 100) system-wide mechanisms have been very…

  2. The Citizens' Perspective in a socio-economic evaluation?

    NARCIS (Netherlands)

    Flinterman, M.; Glasius-Meier, A.

    2005-01-01

    The problem formulation of this quick scan is twofold: Is it possible to fully incorporate the citizens' perspective (for example in the form of experiential value) in a socio-economic evaluation? And does it serve a useful purpose? In this context, the concept of the citizen denotes the user of the

  3. Spectators or Patriots? Citizens in the Information Age

    Science.gov (United States)

    Dhawan, Amrita

    2016-01-01

    In theory, a strong democracy rests on robust citizen participation. The practice in most democracies is quite different. This gap presents a challenge, which can be narrowed by augmenting civic education to bring it up to date with the current information environment and thus give citizens the opportunity to participate. Robert Dahl's work on…

  4. Civic Culture, Community and Citizen Participation in Contrasting Neighbourhoods.

    Science.gov (United States)

    Docherty, Iain; Goodlad, Robina; Paddison, Ronan

    2001-01-01

    Collected data from four urban neighborhoods to explore whether citizen participation in urban governance was fostered by civic culture and local political institutions. Although citizen participation was least likely to occur in poor neighborhoods demonstrating lower educational attainment levels, such factors could be mitigated by political…

  5. Bridging the Gap between Senior Citizens and Young People.

    Science.gov (United States)

    Iannacone, George; Skelly, Joan

    1985-01-01

    This article describes a school district's programs that build relationships between the schools and the local senior citizens, including a grandparent program, developmental seminars, and a prom for senior citizens put on by the students. Also described are some keys to making such programs work, and the benefits. (DCS)

  6. A Citizen Court in the Recombinant DNA debate.

    Science.gov (United States)

    Krinsky, Sheldon

    1978-01-01

    Harvard scientists were planning DNA experiments which required special facilities. A citizen panel was formed to look into the adequacy of federal safety guidelines for the community. Describes the review process and discusses the concept of a citizen court to resolve such technical controversies. (GA)

  7. The political constitution of the EU citizen rights regime

    DEFF Research Database (Denmark)

    Olsen, Tore Vincents

    2011-01-01

    communities and institutions to the good life of citizens, both individually and collectively. Taking the contestation between the different views seriously, the article argues in favour of political constitutionalism, according to which the development of the EU citizen rights regime is the responsibility...

  8. Computer support system for residential environment evaluation for citizen participation

    Institute of Scientific and Technical Information of China (English)

    GE Jian; TEKNOMO Kardi; LU Jiang; HOKAO Kazunori

    2005-01-01

    Though the method of citizen participation in urban planning is quite well established, for a specific segment of residential environment, however, existing participation system has not coped adequately with the issue. The specific residential environment has detailed aspects that need positive and high level involvement of the citizens in participating in all stages and every field of the plan. One of the best and systematic methods to obtain a more involved citizen is through a citizen workshop. To get a more "educated" citizen who participates in the workshop, a special session to inform the citizen on what was previously gathered through a survey was revealed to be prerequisite before the workshop. The computer support system is one of the best tools for this purpose. This paper describes the development of the computer support system for residential environment evaluation system, which is an essential tool to give more information to the citizens before their participation in public workshop. The significant contribution of this paper is the educational system framework involved in the workshop on the public participation system through computer support, especially for residential environment. The framework, development and application of the computer support system are described. The application of a workshop on the computer support system was commented on as very valuable and helpful by the audience as it resulted in greater benefit to have wider range of participation, and deeper level of citizen understanding.

  9. Music, Radio, and Mediatization

    DEFF Research Database (Denmark)

    Krogh, Mads; Michelsen, Morten

    2016-01-01

    Mediatization has become a key concept for understanding the relations between media and other cultural and social fields. Contributing to the discussions related to the concept of mediatization, this article discusses how practices of radio and music(al life) influence each other. We follow Deacon......’s and Stanyer’s advice to supplement the concept of mediatization with ‘a series of additional concepts at lower levels of abstraction’ and suggest, in this respect, the notion of heterogeneous milieus of music– radio. Hereby, we turn away from the all-encompassing perspectives related to the concept...... of mediatization where media as such seem to be ascribed agency. Instead, we consider historical accounts of music–radio in order to address the complex non- linearity of concrete processes of mediatization as they take place in the multiple meetings between a decentred notion of radio and musical life....

  10. The digital sport radio.

    Directory of Open Access Journals (Sweden)

    Hilario José ROMERO BEJARANO

    2014-07-01

    Full Text Available Radio has been immersed in recent years in a phase of technological integration and business of multimedia, as well as diversification of systems and channels for broadcasting. In addition, Internet has been consolidated as the platform of digital radio that more has evolved as a result of its continued expansion. However, the merger radio-Internet must be understood as a new form of communication, and not solely as a new complementary medium. In this context, it is of great interest to analyze that transformations in the way of reception, contents, languages, programs and schedules, has brought with it for the radio that integration. To this end is taken as main reference the sports areas, a key aspect and broadly representative of the current broadcasting landscape.

  11. Everyday Radio Telescope

    CERN Document Server

    Mandal, Pranshu; Kumar, Pratik; Yelikar, Anjali; Soni, Kanchan; T, Vineeth Krishna

    2016-01-01

    We have developed an affordable, portable college level radio telescope for amateur radio astronomy which can be used to provide hands-on experience with the fundamentals of a radio telescope and an insight into the realm of radio astronomy. With our set-up one can measure brightness temperature and flux of the Sun at 11.2 GHz and calculate the beam width of the antenna. The set-up uses commercially available satellite television receiving system and parabolic dish antenna. We report the detection of point sources like Saturn and extended sources like the galactic arm of the Milky way. We have also developed python pipeline, which are available for free download, for data acquisition and visualization.

  12. Boom Booom Net Radio

    DEFF Research Database (Denmark)

    Grimshaw, Mark Nicholas; Yong, Louisa; Dobie, Ian

    1999-01-01

    Internet radio is one of the growth areas of the Internet but, as this article will show, is fraught with difficulties and frustration for both the modestly-funded broadcaster (bitcaster) and the listener. The article will illustrate some of these problems by means of a short case study of an exi......Internet radio is one of the growth areas of the Internet but, as this article will show, is fraught with difficulties and frustration for both the modestly-funded broadcaster (bitcaster) and the listener. The article will illustrate some of these problems by means of a short case study...... of an existing Internet radio station; Boom Booom Net Radio. Whilst necessity dictates some use of technology-related terminology, wherever possible we have endeavoured to keep such jargon to a minimum and to either explain it in the text or to provide further explanation in the appended glossary....

  13. Unveiling the radio cosmos

    Science.gov (United States)

    Vanderlinde, Keith

    2017-02-01

    Using a radio telescope with no moving parts, the dark energy speeding up the expansion of the Universe can be probed in unprecedented detail, says Keith Vanderlinde, on behalf of the CHIME collaboration.

  14. Social cognitive radio networks

    CERN Document Server

    Chen, Xu

    2015-01-01

    This brief presents research results on social cognitive radio networks, a transformational and innovative networking paradigm that promotes the nexus between social interactions and cognitive radio networks. Along with a review of the research literature, the text examines the key motivation and challenges of social cognitive radio network design. Three socially inspired distributed spectrum sharing mechanisms are introduced: adaptive channel recommendation mechanism, imitation-based social spectrum sharing mechanism, and evolutionarily stable spectrum access mechanism. The brief concludes with a discussion of future research directions which ascertains that exploiting social interactions for distributed spectrum sharing will advance the state-of-the-art of cognitive radio network design, spur a new line of thinking for future wireless networks, and enable novel wireless service and applications.

  15. Smart Radio Spectrum Management for Cognitive Radio

    Directory of Open Access Journals (Sweden)

    Partha Pratim Bhattacharya

    2011-08-01

    Full Text Available Today’s wireless networks are characterized by fixed spectrum assignment policy. The limited availablespectrum and the inefficiency in the spectrum usage necessitate a new communication paradigm toexploit the existing wireless spectrum opportunistically. Cognitive radio is a paradigm for wirelesscommunication in which either a network or a wireless node changes its transmission or receptionparameters to communicate efficiently avoiding interference with licensed or unlicensed users. It cancapture best available spectrum to meet user communication requirements (spectrum management. Inthis work, a fuzzy logic based system for spectrum management is proposed where the radio can shareunused spectrum depending on parameters like distance, signal strength, node velocity and availabilityof unused spectrum. The system is simulated and is found to give satisfactory results.

  16. Housewife data: Citizen science and the case of Love Canal

    Science.gov (United States)

    Nicaise, Nolan M.

    Citizen science is defined as members of the public acting to produce science outside of their normal working lives in order to enhance or preserve their health, environment, knowledge, or capital. It is a science by the people. Over the last several decades, it has emerged as a powerful force for the democratization of science. In response to this growing trend in citizen science, this thesis addresses the question: What is citizen science? Citizen science is discussed through the development of a definition, its historical and political context, the benefits of its use, and some frameworks for understanding. Later, the thesis explores a case study of citizen science, the Love Canal environmental crisis, and offers commentary on its methods and findings.

  17. Citizen voices performing public participation in science and environment communication

    CERN Document Server

    Carvalho, Anabela; Doyle, Julie

    2012-01-01

    How is "participation" ascribed meaning and practised in science and environment communication? And how are citizen voices articulated, invoked, heard, marginalised or silenced in those processes? Citizen Voices takes its starting point in the so-called dialogic or participatory turn in scientific and environmental governance in which practices claiming to be based on principles of participation, dialogue and citizen involvement have proliferated. The book goes beyond the buzzword of "participation" in order to give empirically rich, theoretically informed and critical accounts of how citizen participation is understood and enacted in mass mediation and public engagement practices. A diverse series of studies across Europe and the US are presented, providing readers with empirical insights into the articulation of citizen voices in different national, cultural and institutional contexts. Building bridges across media and communication studies, science and technology studies, environmental studies and urban pl...

  18. Beyond technocracy science, politics and citizens

    CERN Document Server

    Bucchi, Massimiano

    2010-01-01

    Nuclear energy, stem cell technology, GMOs: the more science advances, the more society seems to resist. But are we really watching a death struggle between opposing forces, as so many would have it? Can today’s complex technical policy decisions coincide with the needs of a participatory democracy? Are the two sides even equipped to talk to each other? Beyond Technocracy: Science, Politics and Citizens answers these questions with clarity and vision. Drawing upon a broad range of data and events from the United States and Europe, and noting the blurring of the expert/lay divide in the knowledge base, the book argues that these conflicts should not be dismissed as episodic, or the outbursts of irrationality and ignorance, but recognized as a critical opportunity to discuss the future in which we want to live.

  19. Ozone Gardens for the Citizen Scientist

    Science.gov (United States)

    Pippin, Margaret; Reilly, Gay; Rodjom, Abbey; Malick, Emily

    2016-01-01

    NASA Langley partnered with the Virginia Living Museum and two schools to create ozone bio-indicator gardens for citizen scientists of all ages. The garden at the Marshall Learning Center is part of a community vegetable garden designed to teach young children where food comes from and pollution in their area, since most of the children have asthma. The Mt. Carmel garden is located at a K-8 school. Different ozone sensitive and ozone tolerant species are growing and being monitored for leaf injury. In addition, CairClip ozone monitors were placed in the gardens and data are compared to ozone levels at the NASA Langley Chemistry and Physics Atmospheric Boundary Layer Experiment (CAPABLE) site in Hampton, VA. Leaf observations and plant measurements are made two to three times a week throughout the growing season.

  20. Citizen participation, perceived control, and psychological empowerment.

    Science.gov (United States)

    Zimmerman, M A; Rappaport, J

    1988-10-01

    The research integrates the citizen participation literature with research on perceived control in an effort to further our understanding of psychological empowerment. Eleven indices of empowerment representing personality, cognitive, and motivational measures were identified to represent the construct. Three studies examined the relationship between empowerment and participation. The first study examined differences among groups identified by a laboratory manipulation as willing to participate in personally relevant or community relevant situations. Study II examined differences for groups defined by actual involvement in community activities and organizations. Study III replicated Study II with a different population. In each study, individuals reporting a greater amount of participation scored higher on indices of empowerment. Psychological empowerment could be described as the connection between a sense of personal competence, a desire for, and a willingness to take action in the public domain. Discriminant function analyses resulted in one significant dimension, identified as pyschological empowerment, that was positively correlated with leadership and negatively correlated with alienation.

  1. Geeks, meta-Geeks, and gender trouble: activism, identity, and low-power FM radio.

    Science.gov (United States)

    Dunbar-Hester, Christina

    2008-04-01

    In this paper, I consider the activities of a group of individuals who tinker with and build radio hardware in an informal setting called 'Geek Group'. They conceive of Geek Group as a radical pedagogical activity, which constitutes an aspect of activism surrounding citizen access to low-power FM radio. They are also concerned with combating the gendered nature of hardware skills, yet in spite of their efforts men tend to have more skill and familiarity with radio hardware than women. Radio tinkering has a long history as a masculine undertaking and a site of masculine identity construction. I argue that this case represents an interplay between geek, activist, and gendered identities, all of which are salient for this group, but which do not occur together without some tension.

  2. 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...

  3. Dreamers, Poets, Citizens, and Scientists: Motivations for Engaging in GalaxyZoo Citizen Science

    Science.gov (United States)

    Slater, S. J.; Mankowski, T.; Slater, T. F.; CenterAstronomy; Physics Education Research Caper Team

    2010-12-01

    A particularly successful effort to engage the public in science has been to move the nearly countless galaxies imaged by the Sloan Digital Sky Survey to citizen scientists in a project known widely as Galaxy Zoo (URL; http://www.galaxyzoo.org). To everyone’s surprise, the unexpectedly large participation in the website has caused the data set, numbering over a million images, to be classified multiple times, quicker than the project leader anticipated, and continues to boast a high hit count on the website (15 classifications per second). Within 24 hours of launch, the site was receiving 70,000 classifications an hour, and more than 50 million classifications were received by the project during its first year, from almost 150,000 people. In a parallel effort, the Galaxy Zoo forum was created to handle the flood of emails that occurred alongside the flood of classifications, the team hoping that it would encourage the participants to handle each others' questions. By examining the motivations, methods and appeal of Galaxy Zoo to the participating public, other models of citizen science might be purposefully formulated to take advantage of the success exhibited in Galaxy Zoo. In addition, we want to understand the reasons people engage in science in informal settings in order to better enhance teaching methods in formal settings. Although in the past citizen science has primarily been used as a data collection method, there are many new opportunities contained in citizen science motivations and methods that we can use in future applications. This new and innovative method of online citizen science creates data for researchers of galaxies, but there is a parallel set of underlying data that has not yet been deeply analyzed: the motivations and underlying themes within the population of citizen scientists that could lead us to improve future citizen science projects. To address this, we pursued an investigation of the underlying reasons for the success of Galaxy Zoo

  4. Citizen empowerment in volcano monitoring, communication and decision-making at Tungurahua volcano, Ecuador

    Science.gov (United States)

    Bartel, B. A.; Mothes, P. A.

    2013-12-01

    Trained citizen volunteers called vigías have worked to help monitor and communicate warnings about Tungurahua volcano, in Ecuador, since the volcano reawoke in 1999. The network, organized by the scientists of Ecuador's Instituto Geofísico de la Escuela Politécnica Nacional (Geophysical Institute) and the personnel from the Secretaría Nacional de Gestión de Riesgos (Risk Management, initially the Civil Defense), has grown to more than 20 observers living around the volcano who communicate regularly via handheld two-way radios. Interviews with participants conducted in 2010 indicate that the network enables direct communication between communities and authorities; engenders trust in scientists and emergency response personnel; builds community; and empowers communities to make decisions in times of crisis.

  5. Detection of radio continuum emission from Procyon

    Science.gov (United States)

    Drake, Stephen A.; Simon, Theodore; Brown, Alexander

    1993-01-01

    We have detected the F5 IV-V star Procyon as a weak and variable 3.6 cm radio continuum source using the VLA. The inferred radio luminosity is similar to, though some-what higher than, the X-band luminosity of the active and flaring sun. The 33 micro-Jy flux density level at which we detected Procyon on four of five occasions is close to the 36 micro-Jy radio flux density expected from a model in which the radio emission consists of two components: optically thick 'stellar disk' emission with a 3.6 cm brightness temperature of 20,000 K that is 50 percent larger than the solar value, and optically thin coronal emission with an emission measure the same as that indicated by Einstein and EXOSAT X-ray flux measurements in 1981 and 1983. The maximum mass-loss rate of a warm stellar wind is less than 2 x 10 exp -11 solar mass/yr. An elevated flux density of 115 micro-Jy observed on a single occasion provides circumstantial evidence for the existence of highly localized magnetic fields on the surface of Procyon.

  6. The CHIME Fast Radio Burst Project

    Science.gov (United States)

    Kaspi, Victoria M.; CHIME/FRB Collaboration

    2017-01-01

    Fast Radio Bursts are a recently discovered phenomenon consisting of short (few ms) bursts of radio waves that have dispersion measures that strongly suggest an extragalactic and possibly cosmological, but yetunknown, origin. The Canadian Hydrogen Intensity Mapping Experiment was designed to study Baryon Acoustic Oscillations through mapping of redshifted hydrogen, in order to constrain the nature of Dark Energy. CHIME, currently under construction in Penticton, BC in Canada, consists of 4 cylindrical paraboloid reflectors having total collecting area 80 m x 100 m, and will be sensitive in the 400-800 MHz band. With 2048 independent feeds hung along the cylinder axes, CHIME is a transit telescope with no moving parts, but is sensitive to the full ~200 sq. degrees overhead in 1024 formed beams, thanks to the largest correlator ever built. Given CHIME's enormous sensitivity, bandwidth and unprecedented field of view for the radio regime, CHIME will be a superb instrument for studying Fast Radio Bursts, with expected detected event rates of several to several dozen per day, hence promising major progress on the origin and nature of FRBs.

  7. Performance evaluation of cognitive radio in advanced metering infrastructure communication

    Science.gov (United States)

    Hiew, Yik-Kuan; Mohd Aripin, Norazizah; Din, Norashidah Md

    2016-03-01

    Smart grid is an intelligent electricity grid system. A reliable two-way communication system is required to transmit both critical and non-critical smart grid data. However, it is difficult to locate a huge chunk of dedicated spectrum for smart grid communications. Hence, cognitive radio based communication is applied. Cognitive radio allows smart grid users to access licensed spectrums opportunistically with the constraint of not causing harmful interference to licensed users. In this paper, a cognitive radio based smart grid communication framework is proposed. Smart grid framework consists of Home Area Network (HAN) and Advanced Metering Infrastructure (AMI), while AMI is made up of Neighborhood Area Network (NAN) and Wide Area Network (WAN). In this paper, the authors only report the findings for AMI communication. AMI is smart grid domain that comprises smart meters, data aggregator unit, and billing center. Meter data are collected by smart meters and transmitted to data aggregator unit by using cognitive 802.11 technique; data aggregator unit then relays the data to billing center using cognitive WiMAX and TV white space. The performance of cognitive radio in AMI communication is investigated using Network Simulator 2. Simulation results show that cognitive radio improves the latency and throughput performances of AMI. Besides, cognitive radio also improves spectrum utilization efficiency of WiMAX band from 5.92% to 9.24% and duty cycle of TV band from 6.6% to 10.77%.

  8. Orientation of the cores of hybrid morphology radio sources

    CERN Document Server

    Ceglowski, Maciej; Kunert-Bajraszewska, Magdalena

    2013-01-01

    The FRI/FRII dichotomy is a much debated issue in the astrophysics of extragalactic radio sources. Study of the properties of HYbrid MOrphology Radio Sources (HYMORS) may bring crucial information and lead to a step forward in understanding the origin of FRI/FRII dichotomy. HYMORS are a rare class of double-lobed radio sources where each of the two lobes clearly exhibits a different FR morphology. This article describes follow-up high resolution VLBA observations of the five discovered by us HYMORS. The main aim of the observations was to answer the questions of whether the unusual radio morphology is connected to the orientation of objects towards the observer. We obtained the high resolution radio maps of five hybrid radio morphology objects with the VLBA at C-band and L-band. Two of them revealed milliarcsecond core-jet structures, the next two objects showed hints of parsec-scale jets, and the last one remained point-like at both frequencies. We compared properties of observed milliarcsecond structures of...

  9. Geographically Distributed Citizen Scientist Training for the 2017 Citizen CATE Experiment

    Science.gov (United States)

    Gelderman, Richard; Penn, Matt; Baer, Robert; Isberner, Fred; Pierce, Michael; Walter, Donald K.; Yanamandra-Fisher, Padma; Sheeley, Neil R.

    2016-01-01

    The solar eclipse of 21 August 2017 will be visible to over a half billion people across the entire North American continent. The roughly 100-mile wide path of totality, stretching from Oregon to South Carolina, will be the destination for tens of millions of people. In the decades since 1979, when the last total solar eclipse was visible from the continental USA, the phenomenon of Internet enabled citizen science has grown to be an accepted mode for science. The Citizen Continental-America Telescopic Eclipse (Citizen CATE) experiment has been funded as one of the three 2017 eclipse related NASA STEM agreements to engage citizen scientists in a unique, cutting-edge solar physics experiment. Teams across the USA will be trained to use standardized refracting telescope and digital imager set-ups to observe the solar corona during the eclipse, acquiring multiple exposures to create one high dynamic range image. After observing during the eclipse, the CATE volunteers will upload the combined image to a cloud-storage site and the CATE team will then work to properly orient and align all the images collected from across the continent to produce a continuous 90-minutes movie. A time-compressed first cut of the entire sequence will be made available to media outlets on the same afternoon of the eclipse, with hope that high quality images will encourage the most accurate coverage of this Great American Eclipse. We discuss overall the project, as well as details of the initial tests of the prototype set-up (including in the Faroe Islands during the March 2015 total solar eclipse) and plans for the future night-time and day-time observing campaigns, and for a handful of observing teams positioned for overlapping observations of the March 2016 total solar eclipse in the South Pacific.

  10. An Overview of Cassini Radio Science

    Science.gov (United States)

    Kliore, A.; Rappaport, N.; Anabtawi, A.; Asmar, S.; Armstrong, J.; Barbinis, E.; Goltz, G.; Johnston, D.; Fleischman, D.; Rochblatt, D.; Anderson, J.; Marouf, E.; Wong, K.; Thomson, F.; Flasar, F. M.; Schinder, P.; French, R.; McGhee, C.; Mohammed, P.; Steffes, P.; Nagy, A.; Iess, L.; Tortora, P.; Ambrosini, R.; Flamini, E.

    2005-08-01

    The Cassini spacecraft, which has been in orbit about Saturn for over a year, is the first Radio Science platform to provide three downlink frequencies. In addition to the X-band telemetry link (3,56 cm w.l.), two other frequencies, S-band (13.04 cm), and Ka-band (0.94 cm) are available. This, plus the high SNR (>50 dBHz at X-band) afforded by the 4 m diameter s/c high gain antenna in combination with the excellent low noise receivers of the DSN, as well as overall system stabilities of 1 x 10-13 when referenced to the on-board ultra-stable oscillator (USO) in one-way operation, and 1 x 10-15 for a two-way link, make Cassini an unprecedented instrument of radio science. In addition to Gravitational Wave Search and Solar Conjunction experiments conducted during the cruise phase, the orbital tour phase of the mission has as its main radio science objectives: a) determination of the masses and gravity fields of Saturn's icy satellites, Titan, and Saturn through two-way tracking during fly-bys. To date, the masses of Phoebe, Iapetus, Dione and Enceladus have been measured, and will be reported here. b) Measurement of the structure and other properties of Saturn's rings through three-band occultation. Several near-diametric occultations at a high ring opening angle have been completed, and the results will be presented here. c) Measurement of the vertical structure of the atmosphere and ionosphere of Saturn. The same series of occultations have provided nearly equatorial occultations, and the results on the atmosphere structure, the ionosphere, and the abundances of microwave-absorbing gases in Saturn's atmosphere will be described here. In the remaining years of the Cassini mission, these results will be expanded to include the atmosphere, ionosphere, surface, and gravity field of Titan, the gravity field and masses of Saturn and the remaining icy satellites, and the completion of the Saturn objectives described above. The Cassini Radio Science Team wishes to express

  11. Policy makers are from Saturn,..citizens are from Uranus….: Involving citizens in environmental governance in the Drentsche Aa area

    NARCIS (Netherlands)

    van Bommel, S.; Turnhout, E.; Aarts, M.N.C.; Boonstra, F.G.

    2008-01-01

    This study investigated, theoretically as well as empirically, the relationship between public support for nature conservation policy - in the sense of citizen involvement - and governance in Dutch nature policy practices. It involved an in-depth case study of the relation between citizen involvemen

  12. Cross-band broadcasting

    Science.gov (United States)

    Bynum, Leo; Gramann, Mark R.; Bacon, Larry D.

    2015-06-23

    A radio communications device has a modulator that modulates each of a number of different carrier signals with the same message. A combiner combines the modulated carrier signals into a single combined output signal. A radio transmitter receives the single combined output signal and in response simultaneously transmits the modulated carrier signals over the air. Other embodiments are also described.

  13. Natural radio emission of Jupiter as interferences for radar investigations of the icy satellites of Jupiter

    Science.gov (United States)

    Cecconi, B.; Hess, S.; Hérique, A.; Santovito, M. R.; Santos-Costa, D.; Zarka, P.; Alberti, G.; Blankenship, D.; Bougeret, J.-L.; Bruzzone, L.; Kofman, W.

    2012-02-01

    Radar instruments are part of the core payload of the two Europa Jupiter System Mission (EJSM) spacecraft: NASA-led Jupiter Europa Orbiter (JEO) and ESA-led Jupiter Ganymede Orbiter (JGO). At this point of the project, several frequency bands are under study for radar, which ranges between 5 and 50 MHz. Part of this frequency range overlaps with that of the natural jovian radio emissions, which are very intense in the decametric range, below 40 MHz. Radio observations above 40 MHz are free of interferences, whereas below this threshold, careful observation strategies have to be investigated. We present a review of spectral intensity, variability and sources of these radio emissions. As the radio emissions are strongly beamed, it is possible to model the visibility of the radio emissions, as seen from the vicinity of Europa or Ganymede. We have investigated Io-related radio emissions as well as radio emissions related to the auroral oval. We also review the radiation belts synchrotron emission characteristics. We present radio sources visibility products (dynamic spectra and radio source location maps, on still frames or movies), which can be used for operation planning. This study clearly shows that a deep understanding of the natural radio emissions at Jupiter is necessary to prepare the future EJSM radar instrumentation. We show that this radio noise has to be taken into account very early in the observation planning and strategies for both JGO and JEO. We also point out possible synergies with RPW (Radio and Plasma Waves) instrumentations.

  14. Optical Photometric and Radio Monitoring of Gamma-ray Loud Blazars

    Indian Academy of Sciences (India)

    V. S. Bychkova; N. S. Kardashev; M. G. Larionov; A. E. Volvach; V. V. Vlasjuk; O. I. Spiridonova; A. Lächteenmäki; M. Tornikoski; T. Hovatta; E. Nieppola; I. Torniainen; H. D. Aller; M. F. Aller

    2011-03-01

    We present the results of multi-years optical and radio monitoring of radio-loud quasars 0716+714 and 1633+382, aimed at searching the flux variations and possible correlation at different wave bands. Our radio observations were performed with a 22-m radio telescope of the Crimean Astrophysical Observatory, 14-m radio telescope of the Metsahovi Radio Observatory and 26-m telescope of the Michigan Radio Astronomy Observatory at 4.8, 8.0, 14.5, 22.2 and 36.8 GHz. The optical observations were performed with a Zeiss-1000 reflector of the Special Astrophysical Observatory in the B, V, R filters. The harmonic analysis performed for the light curves of 0716+714 from 2002–2010 in radio and optical wave bands revealed the presence of an apparent periodical component in the flux variations. The period of the radio light curve is nearly 3.6 years, and coincides within the errors with the period of the optical light curve (nearly 3.4 years). The duration of the flares is approximately the same in radio and optical ranges, and it is about 100–150 days.

  15. Survey on Cloud Radio Access Network

    Directory of Open Access Journals (Sweden)

    Reeta Chhatani

    2016-01-01

    Full Text Available The existing wireless network will face the challenge of data tsunami in the near future. Densification of network will deal huge data traffic but will increase the interferences and network cost. At the same time, the existing wireless network is underutilized due to dynamic traffic. To deal with this adverse scenario, a change in the current network architecture is required. Based on virtualization, Cloud Radio Access Network (CRAN was proposed for wireless network. In CRAN the functionality of base station will be distributed into base band unit (BBU and remote radio heads (RRH which will achieve benefits of centralization. This paper presents a survey on CRAN centring on optimized resource allocation, energy efficiency and throughput maximization under fronthaul capacity. The existing solution and future opportunities in CRAN are also summarized.

  16. Quark Nova Model for Fast Radio Bursts

    CERN Document Server

    Shand, Zachary; Koning, Nico; Ouyed, Rachid

    2015-01-01

    FRBs are puzzling, millisecond, energetic radio transients with no discernible source; observations show no counterparts in other frequency bands. The birth of a quark star from a parent neutron star experiencing a quark nova - previously thought undetectable when born in isolation - provides a natural explanation for the emission characteristics of FRBs. The generation of unstable r-process elements in the quark nova ejecta provides millisecond exponential injection of electrons into the surrounding strong magnetic field at the parent neutron star's light cylinder via $\\beta$-decay. This radio synchrotron emission has a total duration of hundreds of milliseconds and matches the observed spectrum while reducing the inferred dispersion measure by approximately 200 cm$^{-3}$ pc. The model allows indirect measurement of neutron star magnetic fields and periods in addition to providing astronomical measurements of $\\beta$-decay chains of unstable neutron rich nuclei. Using this model, we can calculate expected FR...

  17. Detecting cosmic rays with the LOFAR radio telescope

    CERN Document Server

    Schellart, P; Buitink, S; Corstanje, A; Enriquez, J E; Falcke, H; Frieswijk, W; Hörandel, J R; Horneffer, A; James, C W; Krause, M; Mevius, M; Scholten, O; ter Veen, S; Thoudam, S; Akker, M van den; Alexov, A; Anderson, J; Avruch, I M; Bähren, L; Beck, R; Bell, M E; Bennema, P; Bentum, M J; Bernardi, G; Best, P; Bregman, J; Breitling, F; Brentjens, M; Broderick, J; Brüggen, M; Ciardi, B; Coolen, A; de Gasperin, F; de Geus, E; de Jong, A; de Vos, M; Duscha, S; Eislöffel, J; Fallows, R A; Ferrari, C; Garrett, M A; Grießmeier, J; Grit, T; Hamaker, J P; Hassall, T E; Heald, G; Hessels, J W T; Hoeft, M; Holties, H A; Iacobelli, M; Juette, E; Karastergiou, A; Klijn, W; Kohler, J; Kondratiev, V I; Kramer, M; Kuniyoshi, M; Kuper, G; Maat, P; Macario, G; Mann, G; Markoff, S; McKay-Bukowski, D; McKean, J P; Miller-Jones, J C A; Mol, J D; Mulcahy, D D; Munk, H; Nijboer, R; Norden, M J; Orru, E; Overeem, R; Paas, H; Pandey-Pommier, M; Pizzo, R; Polatidis, A G; Renting, A; Romein, J W; Röttgering, H; Schoenmakers, A; Schwarz, D; Sluman, J; Smirnov, O; Sobey, C; Stappers, B W; Steinmetz, M; Swinbank, J; Tang, Y; Tasse, C; Toribio, C; van Leeuwen, J; van Nieuwpoort, R; van Weeren, R J; Vermaas, N; Vermeulen, R; Vocks, C; Vogt, C; Wijers, R A M J; Wijnholds, S J; Wise, M W; Wucknitz, O; Yatawatta, S; Zarka, P; Zensus, A

    2013-01-01

    The low frequency array (LOFAR), is the first radio telescope designed with the capability to measure radio emission from cosmic-ray induced air showers in parallel with interferometric observations. In the first $\\sim 2\\,\\mathrm{years}$ of observing, 405 cosmic-ray events in the energy range of $10^{16} - 10^{18}\\,\\mathrm{eV}$ have been detected in the band from $30 - 80\\,\\mathrm{MHz}$. Each of these air showers is registered with up to $\\sim1000$ independent antennas resulting in measurements of the radio emission with unprecedented detail. This article describes the dataset, as well as the analysis pipeline, and serves as a reference for future papers based on these data. All steps necessary to achieve a full reconstruction of the electric field at every antenna position are explained, including removal of radio frequency interference, correcting for the antenna response and identification of the pulsed signal.

  18. Auction based spectrum management of cognitive radio networks

    DEFF Research Database (Denmark)

    Chang, H. B.; Chen, K.-C.; Prasad, Ramjee

    2009-01-01

    (PS-MSs), and we therefore construct a cognitive radio network (CRN) consisting of a PRN with multiple CR-MSs. We propose a spectrum management policy framework such that CR-MSs can compete in utilization of the PRN spectrum bands available to opportunistic transmission of CR-MSs by Vickrey auction......Cognitive radio (CR) technology is considered as an effective solution to enhance overall spectrum efficiency, especially primary radio network (PRN) typically having relatively low spectrum utilization. However, to realize CR concept, it is essential to provide enough incentives to PRN and extra...... to the PRN, the overall spectrum utilization, the profit of the service provider, the spectrum access opportunity of the CR-MSs are increased to achieve cowin situation for every party in cognitive radio networks....

  19. RF environment survey of Space Shuttle related EEE frequency bands

    Science.gov (United States)

    Simpson, J.; Prigel, B.; Postelle, J.

    1977-01-01

    Radio frequency assignments within the continental United States in frequency bands between 121 MHz abd 65 GHz were surveyed and analyzed in order to determine current utilization of anticipated frequency bands for the shuttle borne electromagnetic environment experiment. Data from both government and nongovernment files were used. Results are presented in both narrative form and in histograms which show the total number of unclassified assignments versus frequency and total assigned power versus frequency.

  20. Regulated competition and citizen participation: lessons from Israel.

    Science.gov (United States)

    Chinitz, David

    2000-06-01

    OBJECTIVE: To investigate the relationship between health system structure and citizen participation, in particular whether increased reliance on competition encourages or depresses citizen involvement. SETTING: The case of Israel's ongoing health reform, based on regulated competition among sick funds, is examined. DESIGN: Interviews with government officials and representatives of consumer groups; analysis of policy documents, judicial rulings, public surveys and journalistic accounts. RESULTS: The Israeli reform is based in large measure on a regulated competition model, in which citizens have free choice among highly regulated competing sick funds. At the same time, the reform process has been accompanied by legal, institutional and political frameworks, as well as significant interest group activity, all aimed at increasing public input into processes of health policy making and implementation. The Israeli case, it is argued, lends support to the proposition that citizen participation (voice) and individual choice (exit) are complementary, rather than alternative, modes of ensuring citizen influence over health services. The question is whether the development of multiple avenues for citizen involvement represents disarray or a healthy social learning process regarding the running of the health system. CONCLUSION: This paper expresses cautious optimism that citizen participation is a projection of a healthy social learning process, and suggests directions for public policy to encourage this outcome.

  1. e-Governance Applications for citizens - Issues and Framework

    Directory of Open Access Journals (Sweden)

    S. Prem Kumar,

    2010-10-01

    Full Text Available To bridge the gap between government and citizens, to provide effective and efficient services, to increase productivity and to extend other benefits to its citizens, the governments of various countries introduced e-Governance applications. The applicationsemploy information technology, telecommunication network incorporating government policies over internet to serve the citizens better. The growing importance of e- Governance, spreading its branches in varied fields is going out of control. This is sprouting up new issues giving raise to the unsuccessful penetration of the e-Governance applications and is to be controlled. The three major fields of e-Governance applications are Government to Citizens(G2C, Government to Business(G2B and Government to Government(G2G. The citizens are the power of nation and their satisfaction is ultimate. The government services to citizens should be given utmost importance, as and when it fails resulting in citizen unrest. The problem of this nature is to be minimized with the proposed basic G2Cframe work which includes the elements of Planning, Social Audit, Professional Audit, Audits on Facilities, Performance Audit and Funding. These elements are implemented with quality, security and reliability following the standards of Six Sigma, CapabilityMaturity Model Interface (CMMI and Bureau of Indian Standards (BIS.

  2. Citizen suit Clean Air Act enforcement: An update

    Energy Technology Data Exchange (ETDEWEB)

    Wright, W.G. Jr.

    1999-07-01

    Almost every federal environmental statute has a provision that allows citizens to sue violators in lieu of governmental enforcement authorities under certain circumstances. Generally, if the relevant governmental enforcement authority was not deemed to be diligently prosecuting enforcement action against an alleged violator and certain procedural requirements were met a citizens suit could be filed in federal court. If a violation was proved penalties could be assessed against the violator and the plaintiff citizen could receive reimbursement of both his or her attorney's fees and other expenses. Historically, however, the only federal statute that has been the subject of significant citizens suit activity has been the federal Clean Water Act (CWA). This paper will explore a variety of events that are expected to significantly increase the number of citizen suits CAA permitted facilities will face over the next ten years. The paper will briefly address the role the Title V operating permit will play. It will also include a discussion of how this permit will now encompass specific emission limitations along with a mandate to report exceedances. Further, and equally important, will be the role of the 1997 federal Environmental Protection Agency any credible evidence rule which potentially broadens the type, amount, and accessibility available to a CAA citizen suit plaintiff. This rule along with the additional monitoring data that will be generated by the Title V periodic and compliance assurance monitoring requirements will be an issue. Two important CAA citizen suits will be discussed which illustrate the potential role of credible evidence. Also, recent citizen suit decisions involving other federal environmental statutes with implications for the CAA will be examined. Further, the paper will provide some thoughts on how facilities can protect themselves to the extent possible against citizen suits.

  3. Radio data archiving system

    Science.gov (United States)

    Knapic, C.; Zanichelli, A.; Dovgan, E.; Nanni, M.; Stagni, M.; Righini, S.; Sponza, M.; Bedosti, F.; Orlati, A.; Smareglia, R.

    2016-07-01

    Radio Astronomical Data models are becoming very complex since the huge possible range of instrumental configurations available with the modern Radio Telescopes. What in the past was the last frontiers of data formats in terms of efficiency and flexibility is now evolving with new strategies and methodologies enabling the persistence of a very complex, hierarchical and multi-purpose information. Such an evolution of data models and data formats require new data archiving techniques in order to guarantee data preservation following the directives of Open Archival Information System and the International Virtual Observatory Alliance for data sharing and publication. Currently, various formats (FITS, MBFITS, VLBI's XML description files and ancillary files) of data acquired with the Medicina and Noto Radio Telescopes can be stored and handled by a common Radio Archive, that is planned to be released to the (inter)national community by the end of 2016. This state-of-the-art archiving system for radio astronomical data aims at delegating as much as possible to the software setting how and where the descriptors (metadata) are saved, while the users perform user-friendly queries translated by the web interface into complex interrogations on the database to retrieve data. In such a way, the Archive is ready to be Virtual Observatory compliant and as much as possible user-friendly.

  4. 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...

  5. Attitudes of European citizens towards pig production systems

    DEFF Research Database (Denmark)

    Krystallis, Athanasios; de Barcellos, Marcia Dutra; Kügler, Jens Oliver

    2009-01-01

    pork with specific fat content, and finally the preferred quality characteristics of the pork end-product. The results of the conjoint analysis were used for a subsequent cluster analysis in order to identify European citizen clusters. Respondents' socio-demographic profile, attitudes towards issues...... and the need for an environment-friendly food production were indeed related to citizens' specific attitudes towards pig farming at the cluster level. However, the relationship between citizenship and consumption behaviour was found to be weak. What people think in their role as citizens related to pig...

  6. Citizen radiation monitoring program for the TMI area

    Energy Technology Data Exchange (ETDEWEB)

    Baratta, A.J.; Gricar, B.G.; Jester, W.A.

    1981-07-01

    The purpose of the program was to develop a system for citizens to independently measure radiation levels in and around their communities. This report describes the process by which the Program was developed and operated. It also presents the methods used to select and train the citizens in making and interpreting the measurements. The test procedures used to select the equipment for the program are described as are the results of the testing. Finally, the actual monitoring results are discussed along with the citizens' reactions to the program.

  7. Band structure of semiconductors

    CERN Document Server

    Tsidilkovski, I M

    2013-01-01

    Band Structure of Semiconductors provides a review of the theoretical and experimental methods of investigating band structure and an analysis of the results of the developments in this field. The book presents the problems, methods, and applications in the study of band structure. Topics on the computational methods of band structure; band structures of important semiconducting materials; behavior of an electron in a perturbed periodic field; effective masses and g-factors for the most commonly encountered band structures; and the treatment of cyclotron resonance, Shubnikov-de Haas oscillatio

  8. Comets at radio wavelengths

    CERN Document Server

    Crovisier, Jacques; Colom, Pierre; Biver, Nicolas

    2016-01-01

    Comets are considered as the most primitive objects in the Solar System. Their composition provides information on the composition of the primitive solar nebula, 4.6 Gyr ago. The radio domain is a privileged tool to study the composition of cometary ices. Observations of the OH radical at 18 cm wavelength allow us to measure the water production rate. A wealth of molecules (and some of their isotopologues) coming from the sublimation of ices in the nucleus have been identified by observations in the millimetre and submillimetre domains. We present an historical review on radio observations of comets, focusing on the results from our group, and including recent observations with the Nan\\c{c}ay radio telescope, the IRAM antennas, the Odin satellite, the Herschel space observatory, ALMA, and the MIRO instrument aboard the Rosetta space probe.

  9. ANTENNA OF RADIO CONTROL

    Directory of Open Access Journals (Sweden)

    Ludwig Ilnytskyi

    2015-12-01

    Full Text Available The article is devoted to current issues in the field of radio monitoring. In this article was considered the antenna of radio control, which represents a grid from three vibrators. Threelement antenna array provides simultaneous control of two radio electronic devices that radiates at frequencies that are close to each other. Antenna system using simple technical means provides noise suppression, even if noise will have the same frequency as useful signal. This makes it possible to use the antenna system in conditions of multibeam wave propagation under the adjustment on the most intense by the power beam. Antenna system makes it possible to measure the electromagnetic field intensity, congestion of the frequency spectrum, direction of noise electromagnetic waves incidence, noise electric field intensity.

  10. An analysis of radio pulsar nulling statistics

    Science.gov (United States)

    Biggs, James D.

    1992-01-01

    Survival analysis methods are used to seek correlations between the fraction of null pulsars and other pulsar characteristics for an ensemble of 72 radio pulsars. The strongest correlation is found between the null fraction and the pulse period, suggesting that nulling is a manifestation of a faltering emission mechanism. Correlations are also found between the fraction of null pulses and other parameters that have a strong dependence on the pulse period. The results presented here suggest that nulling is broad-band and may ultimately be explained in terms of polar cap models of pulsar emission.

  11. Recent Seven Years of Radio and Optical Variabilities of Quasar 1156+295

    Indian Academy of Sciences (India)

    Baorong Liu; Xiang Liu

    2014-09-01

    We analyzed the radio (4.8, 8.0 and 14.5 GHz) light curves from UMRAO database and the optical data of quasar 1156+295 and found that the quasar exhibited remarkable quasi-periodic long-term flux variations in both radio and optical bands with a similar variability timescale of 1.2 ± 0.3 yr. In addition, when a cross correlation analysis was adopted to the radio and optical light curves, we found that the optical variations may precede those of the radio e.g., at 14.5 GHz by ∼ 200 days.

  12. Enhanced UWB Radio Channel Model for Short-Range Communication Scenarios Including User Dynamics

    DEFF Research Database (Denmark)

    Kovacs, Istvan Zsolt; Nguyen, Tuan Hung; Eggers, Patrick Claus F.

    2005-01-01

    In this paper we propose a SISO UWB radio channel model for short-range radio link scenarios between a fixed device and a dynamic user hand-held device. The channel model is derived based on novel experimental UWB radio propagation investigations carried out in typical indoor PAN scenarios...... including realistic device and user terminal antenna configurations. The radio channel measurements have been performed in the lower UWB frequency band of 3GHz to 5GHz with a 2x4 MIMO antenna configuration. Several environments, user scenarios and two types of user terminals have been used. The developed...

  13. A SURVEY ON DYNAMIC SPECTRUM ACCESS TECHNIQUES FOR COGNITIVE RADIO

    Directory of Open Access Journals (Sweden)

    Anita Garhwal

    2012-01-01

    Full Text Available Cognitive radio (CR is a new paradigm that utilizes the available spectrum band. The key characteristic ofCR system is to sense the electromagnetic environment to adapt their operation and dynamically vary itsradio operating parameters. The technique of dynamically accessing the unused spectrum band is known asDynamic Spectrum Access (DSA. The dynamic spectrum access technology helps to minimize unusedspectrum bands. In this paper, main functions of Cognitive Radio (CR i.e. spectrum sensing, spectrummanagement, spectrum mobility and spectrum sharing are discussed. Then DSA models are discussedalong with different methods of DSA such as Command and Control, Exclusive-Use, Shared Use of PrimaryLicensed User and Commons method. Game-theoretic approach using Bertrand game model, MarkovianQueuing Model for spectrum allocation in centralized architecture and Fuzzy logic based method are alsodiscussed and result are shown.

  14. Modelling high-resolution spatially-resolved Supernova Remnant spectra with the Sardinia Radio Telescope

    CERN Document Server

    Loru, Sara; Egron, Elise; Iacolina, Noemi; Righini, Simona; Marongiu, Marco; Mulas, Sara; Murtas, Giulia; Simeone, Davide; Pilia, Maura; Bachetti, Matteo; Trois, Alessio; Ricci, Roberto; Melis, Andrea; Concu, Raimondo

    2016-01-01

    Supernova Remnants (SNRs) exhibit spectra featured by synchrotron radio emission arising from the relativistic electrons, and high-energy emission from both leptonic (Bremsstrahlung and Inverse Compton) and hadronic processes (${\\pi}^0$ mesons decay) which are a direct signature of cosmic rays acceleration. Thanks to radio single-dish imaging observations obtained in three frequency bands (1.6, 7, 22 GHz) with the Sardinia Radio Telescope (www.srt.inaf.it), we can model different SNR regions separately. Indeed, in order to disentangle interesting and peculiar hadron contributions in the high-energy spectra (gamma-ray band) and better constrain SNRs as cosmic rays emitters, it is crucial to fully constrain lepton contributions first through radio-observed parameters. In particular, the Bremsstrahlung and Inverse Compton bumps observed in gamma-rays are bounded to synchrotron spectral slope and cut-off in the radio domain. Since these parameters vary for different SNR regions and electron populations, spatially...

  15. 47 CFR 90.259 - Assignment and use of frequencies in the bands 216-220 MHz and 1427-1432 MHz.

    Science.gov (United States)

    2010-10-01

    ... COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES PRIVATE LAND MOBILE RADIO SERVICES Standards for... applicants that establish eligibility in the Industrial/Business Pool. (2) All operation is secondary to the fixed and mobile services, including the Low Power Radio Service. (3) In the 216-217 MHz band, no...

  16. Saber sobre la radio

    OpenAIRE

    Mata, María Cristina; Universidad Nacional de Córdoba. Argentina

    1998-01-01

    La autora propone en este artículo repensar los fundamentos sobre los cuales se estructuran las asignaturas y talleres de radio en las escuelas de Comunicación Social en Latinoamérica, con el proposito de romper la escisión  entre teoría/práctica y de no violentar su complejidad: en la radio, entendida como práctica comunicativa, se juega en primer lugar una "red de vinculaciones e intercambios" en condiciones privilegiadas para la dialoguicidad. En un segundo lugar, asociado al desarrollo de...

  17. Mobile radio channels

    CERN Document Server

    Pätzold, Matthias

    2011-01-01

    Providing a comprehensive overview of the modelling, analysis and simulation of mobile radio channels, this book gives a detailed understanding of fundamental issues and examines state-of-the-art techniques in mobile radio channel modelling. It analyses several mobile fading channels, including terrestrial and satellite flat-fading channels, various types of wideband channels and advanced MIMO channels, providing a fundamental understanding of the issues currently being investigated in the field. Important classes of narrowband, wideband, and space-time wireless channels are explored in deta

  18. Performance Analysis of Downlink Inter-band Carrier Aggregation in LTE-Advanced

    DEFF Research Database (Denmark)

    Wang, Hua; Rosa, Claudio; Pedersen, Klaus

    2011-01-01

    CC can be different. In this paper, we investigate the downlink resource allocation for inter-band CA, i.e., how to assign carrier(s) to different UEs. A simple yet effective G-factor based carrier selection algorithm, which takes both traffic load and radio channel characteristics......Carrier aggregation (CA) is one of the most distinct features for LTE-Advanced systems, which can support a much wider transmission bandwidth up to 100 MHz by aggregating two or more individual component carriers (CCs) belonging to the same (intra-band) or different (inter-band) frequency bands....... With CA, it is possible to schedule a user equipment (UE) on multiple CCs simultaneously. From radio resource management (RRM) perspective, CC selection plays an important role in optimizing the system performance, especially in the case of inter-band CA where the radio propagation characteristics of each...

  19. Teletraffic performance Analysis of Multi-band Overlaid WCDMA Systems

    DEFF Research Database (Denmark)

    Wang, Hua; Iversen, Villy Bæk

    2007-01-01

    of services. In this paper, we present a novel approach for evaluating the teletraffic performance of multi-band overlaid WCDMA systems in terms of time, call, and traffic blocking probabilities of each service class. We convert the radio model into a circuit switched network by introducing the concept...

  20. A Reconfigurable Radio Architecture for Cognitive Radio in Emergency Networks

    NARCIS (Netherlands)

    Zhang, Qiwei; Kokkeler, Andre B.J.; Smit, Gerard J.M.

    2006-01-01

    Cognitive Radio has been proposed as a promising technology to solve today's spectrum scarcity problem. Cognitive Radio is able to sense the spectrum to find the free spectrum, which can be optimally used by Cognitive Radio without causing interference to the licensed user. In the scope of the Adapt

  1. Spectrum management and radio resource management considering cognitive radio systems

    NARCIS (Netherlands)

    Haartsen, Jaap C.; Wieweg, Lasse; Huschke, Jörg

    2005-01-01

    International fora and some national administrations define a cognitive radio (CR) as a pioneering radio communication system that would be capable of altering and adapting its transmitter and receiver parameters based on communication and the exchange of information with related detectable radio co

  2. Radio Fatwa : Islamic Tanya-Jawab Programmes on Radio Dakwah

    NARCIS (Netherlands)

    Sunarwoto,

    2012-01-01

    The present article is a study of radio fatwa in Indonesia with special reference to the Tanya-Jawab genres in radio dakwah.The concept of fatwa has changed over time. Such Islamic Tanya-Jawab programmes broadcast on radio dakwah are important to understand how fatwa is disseminated by means of medi

  3. Enhancing citizen engagement in cancer screening through deliberative democracy.

    Science.gov (United States)

    Rychetnik, Lucie; Carter, Stacy M; Abelson, Julia; Thornton, Hazel; Barratt, Alexandra; Entwistle, Vikki A; Mackenzie, Geraldine; Salkeld, Glenn; Glasziou, Paul

    2013-03-20

    Cancer screening is widely practiced and participation is promoted by various social, technical, and commercial drivers, but there are growing concerns about the emerging harms, risks, and costs of cancer screening. Deliberative democracy methods engage citizens in dialogue on substantial and complex problems: especially when evidence and values are important and people need time to understand and consider the relevant issues. Information derived from such deliberations can provide important guidance to cancer screening policies: citizens' values are made explicit, revealing what really matters to people and why. Policy makers can see what informed, rather than uninformed, citizens would decide on the provision of services and information on cancer screening. Caveats can be elicited to guide changes to existing policies and practices. Policies that take account of citizens' opinions through a deliberative democracy process can be considered more legitimate, justifiable, and feasible than those that don't.

  4. Federal Community of Practice for Crowdsourcing and Citizen Science

    Science.gov (United States)

    The community of practice includes agencies from across the federal government who convene to discuss ideas, activities, barriers, and ethics related to citizen science and crowdsourcing including scientific research, data management, and open innovation.

  5. Current Approaches in Implementing Citizen Science in the Classroom

    Directory of Open Access Journals (Sweden)

    Harsh R. Shah

    2015-12-01

    Full Text Available Citizen science involves a partnership between inexperienced volunteers and trained scientists engaging in research. In addition to its obvious benefit of accelerating data collection, citizen science has an unexplored role in the classroom, from K–12 schools to higher education. With recent studies showing a weakening in scientific competency of American students, incorporating citizen science initiatives in the curriculum provides a means to address deficiencies in a fragmented educational system. The integration of traditional and innovative pedagogical methods to reform our educational system is therefore imperative in order to provide practical experiences in scientific inquiry, critical thinking, and problem solving for school-age individuals. Citizen science can be used to emphasize the recognition and use of systematic approaches to solve problems affecting the community.

  6. Student Attitudes Towards and Impressions of Project Citizen

    Directory of Open Access Journals (Sweden)

    Sara Winstead FRY

    2013-05-01

    Full Text Available Project Citizen is a civic education curriculum used across the United States and internationally, yet research about its impact on students is lacking in the literature. This article reports the results of a preliminary study designed to answer the following questions: What are students’ attitudes toward and perceptions of Project Citizen? How do their attitudes and perceptions compare to those of students who completed senior projects? Tenhigh school students and 23 first-year college students completed a questionnaire designed for this study. Our findings indicate that the high school students had positive perceptions of Project Citizen, and they self-reported anunderstanding and high levels of efficacy regarding civic responsibility. In contrast, the first-year college students had lower levels of efficacy regarding civic responsibility. Our findings suggest the importance of specific learning experiences to help students develop civic knowledge, skills, and dispositions, and indicate the need for further research into civic programs such as Project Citizen

  7. Welfare Technology and Surveillance in Care Work for Elderly Citizens

    DEFF Research Database (Denmark)

    Hansen, Agnete Meldgaard; Kamp, Annette; Grosen, Sidsel Lond;

    ‘Welfare technologies’ are increasingly used in a variety of settings in the Danish welfare state (Mortensen 2015), where they are envisioned as leading to a new and smarter form of welfare state service delivery, promising increased efficiency, better quality, and citizen empowerment (Finansmini......‘Welfare technologies’ are increasingly used in a variety of settings in the Danish welfare state (Mortensen 2015), where they are envisioned as leading to a new and smarter form of welfare state service delivery, promising increased efficiency, better quality, and citizen empowerment...... (Finansministeriet 2014). Based on two ethnographic field studies we discuss how selected technologies facilitate care and surveillance of citizens in different manners and with different consequences for care relationships between citizens and eldercare professionals. We focus on ‘intelligent floors...

  8. A typology for strategies to connect citizen science and management.

    Science.gov (United States)

    Freitag, Amy

    2016-09-01

    One of the often cited benefits of citizen science is better connecting citizens and their science to adaptive management outcomes. However, there is no consensus as to whether this is a reasonable expectation, and if so, how best to approach creating a successful link to management. This review finds cases where the citizen science-management link is explicitly discussed and places each case into a meta-analysis framework that will help define some general successful approaches to forming such a link. We categorize the types of linkages between citizen science and management along two main axes: cooperative to adversarial and deliberate to serendipitous. Cooperative and deliberate types of linkages are the most common, likely due to a mix of causes: that such links are the most commonly written about in the scientific literature, because such links tend to exist for longer amounts of time, and because other types of links tend to drift toward the cooperative/deliberate approach over time.

  9. Current Approaches in Implementing Citizen Science in the Classroom.

    Science.gov (United States)

    Shah, Harsh R; Martinez, Luis R

    2016-03-01

    Citizen science involves a partnership between inexperienced volunteers and trained scientists engaging in research. In addition to its obvious benefit of accelerating data collection, citizen science has an unexplored role in the classroom, from K-12 schools to higher education. With recent studies showing a weakening in scientific competency of American students, incorporating citizen science initiatives in the curriculum provides a means to address deficiencies in a fragmented educational system. The integration of traditional and innovative pedagogical methods to reform our educational system is therefore imperative in order to provide practical experiences in scientific inquiry, critical thinking, and problem solving for school-age individuals. Citizen science can be used to emphasize the recognition and use of systematic approaches to solve problems affecting the community.

  10. Mobilizing Senior Citizens in Co-design Work

    DEFF Research Database (Denmark)

    Malmborg, Lone; Werner, Katharina; Gronvall, Erik;

    2015-01-01

    This paper addresses methodological considerations of participation in design for ageing. Based on the notions of design culture, communities of everyday practice and situated elderliness we present accounts from two settings and discuss methodological issues related to mobilizing senior citizens...

  11. Citizen Participation in School District Negotiations--Boon or Boondoggle?

    Science.gov (United States)

    Shannon, Tom

    1977-01-01

    Advocates public involvement in the whole collective negotiations process, and the formation of a citizens advisory committee on collective negotiation to advise the school board on the issues being proposed or discussed at the bargaining table. (Author/MLF)

  12. Democratizing Process Innovation? On Citizen Involvement in Public Sector BPM

    Science.gov (United States)

    Niehaves, Björn; Malsch, Robert

    ‘Open Innovation’ has been heavily discussed for product innovations; however, an information systems (IS) perspective on ‘process innovation’ has not yet been taken. Analyzing the example of the public sector in Germany, the paper seeks to investigate the factors that hinder and support ‘open process innovation’, a concept we define as the involvement of citizens in business process management (BPM) activities. With the help of a quantitative study (n=358), six factors are examined for their impact on citizen involvement in local government BPM initiatives. The results show that citizen involvement in reform processes is not primarily motivated by the aim of cost reduction, but rather related to legitimacy reasons and the intent to increase employee motivation. Based on these findings, implications for (design) theory and practice are discussed: Instead of detailed collaborative business processes modeling, the key of citizen involvement in public sector BPM lies in communication and mutual understanding.

  13. Can a Diary Encourage Others to be Citizen Scientists?

    Directory of Open Access Journals (Sweden)

    Jerry H. Kavouras

    2015-08-01

    Full Text Available Review of: Diary of a Citizen Scientist Chasing Tiger Beetles and Other New Ways of Engaging the World; Sharman Apt Russell; (2014. Oregon State University Press, Corvallis, OR. 222 pages.

  14. Citizen science on a smartphone: Participants' motivations and learning.

    Science.gov (United States)

    Land-Zandstra, Anne M; Devilee, Jeroen L A; Snik, Frans; Buurmeijer, Franka; van den Broek, Jos M

    2016-01-01

    Citizen science provides researchers means to gather or analyse large datasets. At the same time, citizen science projects offer an opportunity for non-scientists to be part of and learn from the scientific process. In the Dutch iSPEX project, a large number of citizens turned their smartphones into actual measurement devices to measure aerosols. This study examined participants' motivation and perceived learning impacts of this unique project. Most respondents joined iSPEX because they wanted to contribute to the scientific goals of the project or because they were interested in the project topics (health and environmental impact of aerosols). In terms of learning impact, respondents reported a gain in knowledge about citizen science and the topics of the project. However, many respondents had an incomplete understanding of the science behind the project, possibly caused by the complexity of the measurements.

  15. An investigation of the dynamic processes promoting citizen participation.

    Science.gov (United States)

    Foster-Fishman, Pennie G; Collins, Charles; Pierce, Steven J

    2013-06-01

    This study expanded the citizen participation literature by examining the dynamic nature of citizen participation and the extent to which the factors associated with citizen participation may be moderated by resident leadership status. Longitudinal survey data collected from 542 residents in one small Midwestern city implementing a community change initiative provide some insight into the challenges surrounding the promotion of an active citizenry. Within this one community, citizenship behaviors of emergent resident leaders and residents uninterested in a leadership role were influenced, to some extent, by different factors and the importance of these factors shifted in only a 2 years time span. Future research is needed to determine if the dynamics uncovered in this study were due to the initiative or to the nature of citizen participation processes.

  16. Citizen Science Initiatives: Engaging the Public and Demystifying Science.

    Science.gov (United States)

    Van Vliet, Kim; Moore, Claybourne

    2016-03-01

    The Internet and smart phone technologies have opened up new avenues for collaboration among scientists around the world. These technologies have also expanded citizen science opportunities and public participation in scientific research (PPSR). Here we discuss citizen science, what it is, who does it, and the variety of projects and methods used to increase scientific knowledge and scientific literacy. We describe a number of different types of citizen-science projects. These greatly increase the number of people involved, helping to speed the pace of data analysis and allowing science to advance more rapidly. As a result of the numerous advantages of citizen-science projects, these opportunities are likely to expand in the future and increase the rate of novel discoveries.

  17. Mobilizing Senior Citizens in Co-Design of Mobile Technology

    DEFF Research Database (Denmark)

    Malmborg, Lone; Gronvall, Erik; Messeter, Jörn

    2016-01-01

    &Take project. Challenges for mobilization are identified, based on an analysis of attitudes and values among design researchers and senior citizens. This analysis lead us to identify and discuss three strategies for mobilizing senior citizens in co-design of mobile technology: 1) Understanding being ‘elderly......This paper disseminates work from the European Give&Take project, which aims at co-designing service sharing among senior citizens based on a mobile and distributed platform. With this project as a frame, our paper addresses methodological considerations of participation in co-design for ageing....... Based on the notions of design culture, communities of everyday practice and situated elderliness we present accounts from two European countries, and discuss methodological issues related to mobilizing senior citizens in co-design work as they have manifested themselves and influenced the Give...

  18. Band parameters of phosphorene

    DEFF Research Database (Denmark)

    Lew Yan Voon, L. C.; Wang, J.; Zhang, Y.;

    2015-01-01

    Phosphorene is a two-dimensional nanomaterial with a direct band-gap at the Brillouin zone center. In this paper, we present a recently derived effective-mass theory of the band structure in the presence of strain and electric field, based upon group theory. Band parameters for this theory...

  19. Valuing future citizens' values regarding risk

    Energy Technology Data Exchange (ETDEWEB)

    Fleming, Patricia [Creighton Univ., Omaha (United States). College of Arts and Sciences/Philosophy

    2006-09-15

    Valuing present citizen's values regarding the risks they face is an important aspect of risk assessment and risk acceptability. Conferences like VALDOR are held for this reason. Governments like Sweden have national referendums on various risk-prone enterprises. The results of these referendums can determine the future of these programs. In the United States, when guidelines are set for determining acceptable levels of risk, the relevant federal agencies are often required to provide a comment period regarding proposed guidelines in order to ascertain the judgments, including the weights place on certain values, of individual members of society as well as stakeholder groups. After the comment period ends, the agency decides on the acceptable level of risk, taking into account the comments from present citizens. Do we also have a duty to value the not-yet-existing values of future citizens, especially if the risks created by the activities of present citizens extend into the future to citizens not yet living? If so, are there any circumstances which entitle us to de-value those not-yet-existing values. In this paper, I ground my discussion of the question of valuing future citizens' values in one of the areas of focus of the VALDOR conference: nuclear waste management and specifically the question facing the United States' program regarding an acceptable dose standard associated with the release of radioactivity into the biosphere from an underground repository. The underlying conference theme to which this discussion may be attached is community environmental justice as it applies to future citizens. I focus on the role that uncertainty plays is providing justice between present and future citizens.

  20. Social Rights of EU Migrant Citizens: A Comparative Perspective

    OpenAIRE

    Martin Seeleib-Kaiser; Cecilia Bruzelius; Elaine Chase

    2015-01-01

    Access to social rights is core for the ability of all citizens irrespective of class to more fully enjoy political and civil rights. The development of EU citizenship over the past twenty years has made great progress in granting social rights not only to workers, but also to EU citizens, who fulfil certain minimum residency requirements. These developments are, however, not fully underpinned by the necessary political legitimacy in all Member States. Although across Member States one can de...

  1. Fine spectral structures in Jovian decametric radio emission observed by ground-based radio telescope.

    Science.gov (United States)

    Panchenko, M.; Brazhenko, A. I.; Shaposhnikov, V. E.; Konovalenko, A. A.; Rucker, H. O.

    2014-04-01

    Jupiter with the largest planetary magnetosphere in the solar system emits intense coherent non-thermal radio emission in a wide frequency range. This emission is a result of a complicated interaction between the dynamic Jovian magnetosphere and energetic particles supplying the free energy from planetary rotation and the interaction between Jupiter and the Galilean moons. Decametric radio emission (DAM) is the strongest component of Jovian radiation observed in a frequency range from few MHz up to 40 MHz. This emission is generated via cyclotron maser mechanism in sources located along Jovian magnetic field lines. Depending on the time scales the Jovian DAMexhibits different complex spectral structures. We present the observations of the Jovian decametric radio emission using the large ground-based radio telescope URAN- 2 (Poltava, Ukraine) operated in the decametric frequency range. This telescope is one of the largest low frequency telescopes in Europe equipped with high performance digital radio spectrometers. The antenna array of URAN-2 consists of 512 crossed dipoles with an effective area of 28 000m2 and beam pattern size of 3.5 x 7 deg. (at 25 MHz). The instrument enables continuous observations of the Jovian radio during long period of times. Jovian DAM was observed continuously since Sep. 2012 (depending on Jupiter visibility) with relatively high time-frequency resolution (4 kHz - 100ms) in the broad frequency range (8-32MHz). We have detected a big amount of the fine spectral structures in the dynamic spectra of DAM such as trains of S-bursts, quasi-continuous narrowband emission, narrow-band splitting events and zebra stripe-like patterns. We analyzed mainly the fine structures associated with non-Io controlled DAM. We discuss how the observed narrowband structures which most probably are related to the propagation of the decametric radiation in the Jupiter's ionosphere can be used to study the plasma parameters in the inner Jovian magnetosphere.

  2. Low Power Band to Band Tunnel Transistors

    Science.gov (United States)

    2010-12-15

    the E-field and tunneling at the source- pocket junction you form a parasitic NPN + transistor and the injection mechanism of carriers into the...hypothesis that the 1000 ° C, 5s anneal split lead to a very wide pocket and the accidental formation of a NPN + transistor , while the 1000 ° C, 1s anneal...Low Power Band to Band Tunnel Transistors Anupama Bowonder Electrical Engineering and Computer Sciences University of California at Berkeley

  3. Educational Broadcasting--Radio.

    Science.gov (United States)

    Ahamed, Uvais; Grimmett, George

    This manual is intended for those who must conduct educational radio broadcasting training courses in Asia-Pacific countries without the resources of experienced personnel, as well as for individuals to use in self-learning situations. The selection of material has been influenced by the need to use broadcasting resources effectively in programs…

  4. Valuing commercial radio licences

    NARCIS (Netherlands)

    Kerste, M.; Poort, J.; van Eijk, N.

    2011-01-01

    Within the EU Regulatory Framework, licensees for commercial radio broadcasting may be charged a fee to ensure optimal allocation of scarce resources but not to maximize public revenues. In this paper, it is described how such a fee can be determined for the purpose of licence renewal or extension.

  5. Albanian: Basic Radio Communications.

    Science.gov (United States)

    Defense Language Inst., Washington, DC.

    This volume has been designed as a supplement to a course in Albanian developed by the Defense Language Institute. The emphasis in this text is placed on radio communications instruction. The volume is divided into five exercises, each of which contains a vocabulary, dictation, and an air-to-ground communications procedure conducted in Albanian…

  6. Svetloe Radio Astronomical Observatory

    Science.gov (United States)

    Smolentsev, Sergey; Rahimov, Ismail

    2013-01-01

    This report summarizes information about the Svetloe Radio Astronomical Observatory activities in 2012. Last year, a number of changes took place in the observatory to improve some technical characteristics and to upgrade some units to their required status. The report provides an overview of current geodetic VLBI activities and gives an outlook for the future.

  7. Zelenchukskaya Radio Astronomical Observatory

    Science.gov (United States)

    Smolentsev, Sergey; Dyakov, Andrei

    2013-01-01

    This report summarizes information about Zelenchukskaya Radio Astronomical Observatory activities in 2012. Last year a number of changes took place in the observatory to improve some technical characteristics and to upgrade some units to the required status. The report provides an overview of current geodetic VLBI activities and gives an outlook for the future.

  8. Land-losing Farmers’ Citizenization in the Process of Urbanization

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Starting from the status of citizenization of land-losing farmers,problems in the citizenization are analyzed,such as the difficulty in land-losing farmers’ economic life after turning into citizens,employment difficulties of land-losing farmers after living in the city,and the prominent problems in social security of land-losing farmers.Causations for the citizenization problems of land-losing farmers are analyzed.Firstly,institutionalized rejection is the root of the obstacle in citizenization of land-losing farmers.Secondly,exclusion from social security system is a fundamental reason.Thirdly,exclusion of land-losing farmers from both urban citizens and themselves is the subjective factor.Fourthly,exclusion of land-losing farmers from urban employment is the objective factor.Based on these,countermeasures are put forward:formulating a reasonable price of land transfer;establishing a reasonable land compensation and benefit-sharing mechanism;setting up a multi-level social security system for land-losing farmers;increasing the human capital investment in land-losing farmers to enhance their employment status;and improving the cultural quality of land-losing farmers to realize the change in lifestyle.

  9. The Power of Engaging Citizen Scientists for Scientific Progress

    Directory of Open Access Journals (Sweden)

    Jeanne Garbarino

    2015-11-01

    Full Text Available Citizen science has become a powerful force for scientific inquiry, providing researchers with access to a vast array of data points while connecting nonscientists to the authentic process of science. This citizen-researcher relationship creates an incredible synergy, allowing for the creation, execution, and analysis of research projects that would otherwise prove impossible in traditional research settings, namely due to the scope of needed human or financial resources (or both. However, citizen-science projects are not without their challenges. For instance, as projects are scaled up, there is concern regarding the rigor and usability of data collected by citizens who are not formally trained in research science. While these concerns are legitimate, we have seen examples of highly successful citizen-science projects from multiple scientific disciplines that have enhanced our collective understanding of science, such as how RNA molecules fold or determining the microbial metagenomic snapshot of an entire public transportation system. These and other emerging citizen-science projects show how improved protocols for reliable, large-scale science can realize both an improvement of scientific understanding for the general public and novel views of the world around us.

  10. The Power of Engaging Citizen Scientists for Scientific Progress.

    Science.gov (United States)

    Garbarino, Jeanne; Mason, Christopher E

    2016-03-01

    Citizen science has become a powerful force for scientific inquiry, providing researchers with access to a vast array of data points while connecting nonscientists to the authentic process of science. This citizen-researcher relationship creates an incredible synergy, allowing for the creation, execution, and analysis of research projects that would otherwise prove impossible in traditional research settings, namely due to the scope of needed human or financial resources (or both). However, citizen-science projects are not without their challenges. For instance, as projects are scaled up, there is concern regarding the rigor and usability of data collected by citizens who are not formally trained in research science. While these concerns are legitimate, we have seen examples of highly successful citizen-science projects from multiple scientific disciplines that have enhanced our collective understanding of science, such as how RNA molecules fold or determining the microbial metagenomic snapshot of an entire public transportation system. These and other emerging citizen-science projects show how improved protocols for reliable, large-scale science can realize both an improvement of scientific understanding for the general public and novel views of the world around us.

  11. The Internet and Increased Citizen Participation in Government

    Directory of Open Access Journals (Sweden)

    Michael E. Milakovich

    2010-04-01

    Full Text Available What roles do communication systems, information technologies and the internet play in fostering citizen participation and influencing the electoral and administrative decisions of government? The internet is simultaneously a world-wide broadcasting network, a mechanism for information dissemination, and a medium for collaboration and interaction between individuals and their computers without regard for geographic boundaries or time zones. This article describes the origins of participatory democracy, discusses how modern concepts of democracy link to citizen participation, and describes the ways that newly-created spaces on the internet referred to as “polispheres” are being used by political activists and candidates to facilitate wider collaboration and citizen participation. The following questions are addressed: What role does the internet play in fostering and aiding citizen participation in government? Does increased involvement lead to greater trust and confidence in government? What role did the internet play in apparently reversing downward trends in citizen apathy and drawing 8 million new voters to the United States 2008 presidential election? The article suggests that information technology facilitates broader citizen participation and identifies the challenges facing governments in adopting internet-based ICT strategies.

  12. PERFORMANCE OPTIMIZATION OF COGNITIVE RADIO WITH WIDEBAND SPECTRUM SENSING

    Directory of Open Access Journals (Sweden)

    E. Saraniya

    2014-09-01

    Full Text Available Cognitive radio (CR technology allows the unlicensed user to access the licensed spectrum bands. Spectrum sensing is an essential function in cognitive radio to detect the spectrum holes and opportunistically use the underutilized frequency bands without causing interference to primary user (PU. In this paper we are maximizing the throughput capacity of cognitive radio user and hence the performance of spectrum sensing and protection to licensed user improves over a wideband spectrum sensing band. The simulation of cognitive radio is done by analyzing the performance of energy detector spectrum sensing technique to detect primary user and to formulate the optimization using multiband joint detection method (MJD to achieve suitable trade- off between secondary user access and primary user network. The main aim of this paper is to maximize the probability of detection and to decrease the probabilities of miss detection and false alarm. To maximize the throughput it requires minimizing the throughput loss caused by miss detection and the significant reduction in probability of false alarm helps in achieving the spectral efficiency from the secondary user’s perspective. The simulation results show that the performance increases with the MJD method.

  13. Exploiting the Terahertz Band for Radionavigation

    Science.gov (United States)

    Parker, John Scott; Mickelson, Pascal; Yeak, Jeremy; Kremeyer, Kevin; Rife, Jason

    2016-10-01

    This paper demonstrates the feasibility of GPS-like ranging at terahertz (THz) frequencies. It is well established that GPS carrier signals are vulnerable to jamming via radio-frequency interference (RFI). As a result, there is a need for alternative radionavigation systems. THz signals offer a compelling option. Because of their high frequency (roughly ×100 higher than GPS), THz signals can be used to make highly precise range measurements. In addition, the large separation between the GPS and THz frequencies means that interference at GPS frequencies is very unlikely to impact the THz band. This paper lays the groundwork for a GPS-like ranging capability at THz frequencies. To this end, we identify key differences between THz hardware and GPS (radio frequency) hardware; we experimentally evaluate performance of a 0.30-THz system on a compact outdoor test range, and we introduce a measurement error model that highlights the distinctive role that multipath interference plays at THz frequencies.

  14. Multi-Band Feeds: A Design Study

    CERN Document Server

    Maan, Yogesh; Raja, Wasim; Mehta, Nikhil

    2012-01-01

    Broadband antenna feeds are of particular interest to existing and future radio telescopes for multi-frequency studies of astronomical sources. Although a 1:15 range in frequency is difficult to achieve, the well-known Eleven feed design offers a relatively uniform response over such a range, and reasonably well-matched responses in E & H planes. However, given the severe Radio Frequency Interference in several bands over such wide spectral range, one desires to selectively reject the corresponding bands. With this view, we have explored the possibilities of having a multi-band feed antenna spanning a wide frequency range, but which would have good response only in a number of pre-selected (relatively) RFI-free windows (for a particular telescope-site). The designs we have investigated use the basic configuration of pairs of dipoles as in the Eleven feed, but use simple wire dipoles instead of folded dipoles used in the latter. From our study of the two designs we have investigated, we find that the desig...

  15. Digital Audio Radio Broadcast Systems Laboratory Testing Nearly Complete

    Science.gov (United States)

    2005-01-01

    Radio history continues to be made at the NASA Lewis Research Center with the completion of phase one of the digital audio radio (DAR) testing conducted by the Consumer Electronics Group of the Electronic Industries Association. This satellite, satellite/terrestrial, and terrestrial digital technology will open up new audio broadcasting opportunities both domestically and worldwide. It will significantly improve the current quality of amplitude-modulated/frequency-modulated (AM/FM) radio with a new digitally modulated radio signal and will introduce true compact-disc-quality (CD-quality) sound for the first time. Lewis is hosting the laboratory testing of seven proposed digital audio radio systems and modes. Two of the proposed systems operate in two modes each, making a total of nine systems being tested. The nine systems are divided into the following types of transmission: in-band on-channel (IBOC), in-band adjacent-channel (IBAC), and new bands. The laboratory testing was conducted by the Consumer Electronics Group of the Electronic Industries Association. Subjective assessments of the audio recordings for each of the nine systems was conducted by the Communications Research Center in Ottawa, Canada, under contract to the Electronic Industries Association. The Communications Research Center has the only CCIR-qualified (Consultative Committee for International Radio) audio testing facility in North America. The main goals of the U.S. testing process are to (1) provide technical data to the Federal Communication Commission (FCC) so that it can establish a standard for digital audio receivers and transmitters and (2) provide the receiver and transmitter industries with the proper standards upon which to build their equipment. In addition, the data will be forwarded to the International Telecommunications Union to help in the establishment of international standards for digital audio receivers and transmitters, thus allowing U.S. manufacturers to compete in the

  16. Beyond empowerment: building a company of citizens.

    Science.gov (United States)

    Manville, Brook; Ober, Josiah

    2003-01-01

    We live in a knowledge economy. The core assets of the modern business enterprise aren't its buildings, machinery, and real estate, but the intelligence, understanding, skills, and experience of its employees. Harnessing the capabilities and commitment of knowledge workers is arguably the central managerial challenge of our time. Unfortunately, it is a challenge that has not yet been met. Corporate ownership structures, governance systems, and incentive programs--despite the enlightened rhetoric of business leaders--remain firmly planted in the industrial age. In this article, the authors draw on history to lay out a model for a democratic business organization suited to the knowledge economy. Some 2,500 years ago, the city-state of ancient Athens rose to unprecedented political and economic power by giving its citizens a direct voice and an active role in civic governance. The city's uniquely participative system of democracy helped unleash the creativity of the Athenian people and channel it to produce the greatest good for society. The system succeeded in bringing individual initiative and common cause into harmony. And that is precisely the synthesis today's companies need to achieve if they're to realize the full power of their people and thrive in the knowledge economy. The Athenian model of organizational democracy is just that--a model. It does not provide a simple set of prescriptions for modern managers. What it offers is a window into how sizable groups of people can, in an atmosphere of dignity and trust, successfully govern themselves without resorting to a stifling bureaucracy.

  17. INOVASI RADIO KAMPUS (RANCANG BANGUN RADIO UDINUS DENGAN INOVASI TEKNOLOGI @RADIO

    Directory of Open Access Journals (Sweden)

    Wellia Shinta Sari

    2014-08-01

    Full Text Available Perkembangan Teknologi Informasi dan Komunikasi (TIK memaksa industri penyiaran untuk ikut menyesuaikan diri. Radio konvensional bisa jadi akan tertinggal jika tidak melakukan inovasi teknologi yang ada. Begitu juga dengan radio kampus, yang keberadaannya sangat dibutuhkan sebagai wadah kreativitas dan sarana pembelajaran di sebuah universitas, apalagi yang memiliki program studi penyiaran. Radio kampus Suara Dian yang masih konvensional sehingga hampir kehilangan eksistensinya harus segera dibenahi dan dihidupkan kembali dengan mengikuti perkembangan teknologi di era konvergensi. Metode Inovasi teknologi yang bisa dilakukan adalah dengan menggunakan teknologi @Radio Streaming, yang bukan sekedar streaming, tapi juga optimalisasi teknologi yang terintegrasi dinamis melalui RISE (Radio Broadcasting Integrated System. Dengan berbagai fitur unggul dari inovasi teknologi tersebut, maka diharapkan Radio kampus Udinus ”Suara Dian” dapat kembali hidup, berkembang dan lebih kompetitif ditengah industri penyiaran Radio. Kata kunci : radio, kampus, konvergensi, streaming.

  18. The importance of Radio Quiet Zone (RQZ) for radio astronomy

    Science.gov (United States)

    Umar, Roslan; Abidin, Zamri Zainal; Ibrahim, Zainol Abidin

    2013-05-01

    Most of radio observatories are located in isolated areas. Since radio sources from the universe is very weak, astronomer need to avoid radio frequency interference (RFI) from active spectrum users and radio noise produced by human made (telecommunication, mobile phone, microwave user and many more. There are many observatories around the world are surrounded by a Radio Quiet Zone (RQZ), which is it was set up using public or state laws. A Radio Quiet Zone normally consists of two areas: an exclusive area in which totally radio emissions are forbidden, with restrictions for residents and business developments, and a larger (radius up to 100 km above) coordination area where the power of radio transmission limits to threshold levels. Geographical Information System (GIS) can be used as a powerful tool in mapping large areas with varying RQZ profiles. In this paper, we report the initial testing of the usage of this system in order to identify the areas were suitable for Radio Quiet Zone. Among the important parameters used to develop the database for our GIS are population density, information on TV and telecommunication (mobile phones) transmitters, road networks (highway), and contour shielding. We will also use other information gathered from on-site RFI level measurements on selected 'best' areas generated by the GIS. The intention is to find the best site for the purpose of establishing first radio quiet zones for radio telescope in Malaysia.

  19. Effects of implanted radio transmitters with percutaneous antennas on the behavior of Canada Geese

    Science.gov (United States)

    Hupp, J.W.; Ruhl, G.A.; Pearce, J.M.; Mulcahy, D.M.; Tomeo, M.A.

    2003-01-01

    We examined whether surgically-implanted radio transmitters with percutaneous antennas affected behavior of Lesser Canada Geese (Branta canadensis parvipes) in Anchorage, Alaska. We implanted either a 26-g VHF radio transmitter or a larger VHF radio that was the same mass (35 g) and shape as a satellite transmitter in the coelom of adult females captured during molt in 2000. A control group of females was marked with leg bands. We simultaneously observed behavior of radio-marked and control females from 4-62 d following capture. We observed no differences in the proportion of time birds in different treatments allocated among grazing, resting, comfort, walking, and alert behavior. Females in different treatments spent a similar proportion of time in the water. Implantation of radio transmitters did not affect the frequency of agonistic interactions. We conclude that coelomic radio transmitters with percutaneous antennas had minimal effects on the behavior of Canada Geese.

  20. Design of BPS digital frontend for software defined radio receiver

    Institute of Scientific and Technical Information of China (English)

    王洪梅; KIM Jae-hyung; 王法广; LEE Sang-hyuk; 王雪松

    2015-01-01

    In radio receivers, complete implementation of the software defined radio (SDR) concept is mainly limited by frontend. Based on bandpass sampling (BPS) theory, a flexible digital frontend (DFE) platform for SDR receiver is designed. In order to increase the processing speed, Gigabit Ethernet was applied in the platform at speed of 5×108 bit/s. By appropriate design of interpolant according to the position of input RF signals, multi-band receiving can be realized in the platform with suppression more than 35 dB without changing hardware.

  1. The Role of Citizen Science and Crowdsourcing Tools in Supporting Systems Analysis at IIASA

    OpenAIRE

    Fritz, S; L. See; Moorthy, I.; McCallum, I.; Perger, C; Shchepashchenko, D.; Lesiv, M.; Shvidenko, A; Salk, C.; Dürauer, M.; Karner, M; Sturn, T.; Dresel, C.; Domian, D.; Dunwoody, A.

    2015-01-01

    The involvement of citizens in scientific activities from data collection to hypothesis generation is referred to as citizen science. The majority of citizen involvement tends to be on the data collection side, where numerous crowdsourcing platforms have been built to involve citizens in image interpretation, online mapping and other micro-tasks that would not otherwise have been possible. There has been increasing attention directed towards how citizen-contributed data can be used for improv...

  2. ALMA Band 5 Cartridge Performance

    Science.gov (United States)

    Billade, Bhushan; Lapkin, I.; Nystrom, O.; Sundin, E.; Fredrixon, M.; Finger, R.; Rashid, H.; Desmaris, V.; Meledin, D.; Pavolotsky, A.; Belitsky, Victor

    2010-03-01

    Work presented here concerns the design and performance of the ALMA Band 5 cold cartridge, one of the 10 frequency channels of ALMA project, a radio interferometer under construction at Atacama Desert in Chile. The Band 5 cartridge is a dual polarization receiver with the polarization separation performed by orthomode transducer (OMT). For each polarization, Band 5 receiver employs sideband rejection (2SB) scheme based on quadrature layout, with SIS mixers covering 163-211 GHz with 4-8 GHz IF. The LO injection circuitry is integrated with mixer chip and is implemented on the same substrate, resulting in a compact 2SB assembly. Amongst the other ALMA bands, the ALMA Band 5 being the lowest frequency band that uses all cold optics, has the largest mirror. Consequently, ALMA Band 5 mirror along with its support structure leaves very little room for placing OMT, mixers and IF subsystems. The constraints put by the size of cold optics and limited cartridge space, required of us to revise the original 2SB design and adopt a design where all the components like OMT, mixer, IF hybrid, isolators and IF amplifier are directly connected to each other without using any co-ax cables in-between. The IF subsystem uses the space between 4 K and 15 K stage of the cartridge and is thermally connected to 4 K stage. Avoiding co-ax cabling required use of custom designed IF hybrid, furthermore, due to limited cooling capacity at 4 K stage, resistive bias circuitry for the mixers is moved to 15 K stage and the IF hybrid along with an integrated bias-T is implemented using superconducting micro-strip lines. The E-probes for both LO and RF waveguide-to-microstrip transitions are placed perpendicular to the wave direction (back-piece configuration). The RF choke at the end of the probes provides a virtual ground for the RF/LO signal, and the choke is DC grounded to the chassis. The on-chip LO injection is done using a microstrip line directional coupler with slot-line branches in the

  3. 47 CFR 15.223 - Operation in the band 1.705-10 MHz.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false Operation in the band 1.705-10 MHz. 15.223 Section 15.223 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Intentional Radiators Radiated Emission Limits, Additional Provisions § 15.223 Operation in the band...

  4. New space research frequency band proposals in the 20- to 40.5-GHz range

    Science.gov (United States)

    Bishop, D. F.

    1991-01-01

    Future space research communications systems may require spectra above 20 GHz. Frequency bands above 20 GHz are identified that are suitable for space research. The selection of the proper bands depends on consideration of interference with other radio services, adequate bandwidths, link performance, and technical requirements for practical implementation.

  5. 75 FR 9850 - Tank Level Probing Radars in the Frequency Band 77-81 GHz

    Science.gov (United States)

    2010-03-04

    ... frequency band. Radiated emission limits. Siemens requests that the Commission establish a peak EIRP level... obtain comments regarding proposed changes to the regulations for radio frequency devices that do not... COMMISSION 47 CFR Part 15 Tank Level Probing Radars in the Frequency Band 77-81 GHz AGENCY:...

  6. Digital filters in radio detectors of the Pierre Auger Observatory

    Science.gov (United States)

    Szadkowski, Zbigniew; Głas, Dariusz

    2016-09-01

    Ultra-high energy cosmic rays (UHECR) are the most energetic observable particles in Universe. The main challenge in detecting such energetic particles is very small flux. Most experiments focus on detecting Extensive Air Showers (EAS), initiated by primary UHECR particle in interaction with particles of the atmosphere. One of the observation method is detecting the radio emission from the EAS. This emission was theoretically suggested in 1960's, but technological development allow successful detection only in the last several years. This detection technique is used by Auger Engineering Radio Array (AERA). Most of the emission can be observed in frequency band 30 - 80 MHz, however this range is contaminated by radio frequency interferences (RFI). These contaminations must be reduced to decrease false trigger rate. Currently, there are two kind of digital filters used in AERA. One of them is median filter, based on Fast Fourier Transform. Second one is the notch filter, which is a composition of four infinite impulse response filters. Those filters have properly work in AERA radio detectors for many years. Dynamic progress in electronics allows to use more sophisticated algorithms of RFI reduction. Planned modernization of the AERA radio detectors' electronic allows to use finte impulse response (FIR) filters, which can fast adapt to environment conditions. These filters are: Least Mean Squares (LMS) filter and filter based on linear prediction (LP). Tests of new kind of filters are promising and show that FIR filters can be used in next generation radio detectors in AERA experiment.

  7. A Search for Fast Radio Bursts in GALFACTS data

    Science.gov (United States)

    Cohen, Tyler; Salter, Christopher J.; Ghosh, Tapasi

    2016-01-01

    Fast Radio Bursts (FRBs) are transient radio sources whose high dispersion measures suggest they are of extra-galactic origin. They are particularly difficult to detect because, unlike other fast radio transients, they are non-recurring events. At present, 11 such bursts have been detected, 10 by the Parkes Radio Telescope and one by Arecibo Observatory. The G-ALFA Continuum Transit Survey (GALFACTS) is the highest resolution, full-Stokes, radio-continuum survey of the foreground sky. The Arecibo radio telescope is the largest single-aperture telescope in the world, offering the superior point-source sensitivity necessary to detect additional FRBs. GALFACTS utilizes Arecibo's ALFA receiver, an L-band 7-beam feed array, to produce a high-time (1 ms), low-spectral (MHz) resolution (HTLS) data stream between 1225 and 1525 MHz. We used ``Red_Transient", a robust search pipeline developed by A.A. Deshpande, to de-disperse the HTLS data with the intention of detecting FRBs in the ~30% of the total sky surveyed by GALFACTS. Concurrently, the student produced a similar search pipeline to calibrate HTLS data and validate detections by ``Red_Transient". Here, we present the results of initial processing runs on the first several days of GALFACTS observations. Currently, no FRB detections have been found. However, the detection of pulses from the known pulsar J1916+1312 indicates that ``Red_Transient" is capable of detecting fast transient signals present in the data stream.

  8. Unmanned Aircraft Systems (UAS) Integration in the National Airspace System (NAS) Project - Gen-4 and Gen-5 Radio Plans

    Science.gov (United States)

    Griner, James H.

    2014-01-01

    NASA's UAS Integration in the NAS project, has partnered with Rockwell Collins to develop a concept Control and Non-Payload Communication (CNPC) system prototype radio, operating on recently allocated UAS frequency spectrum bands. This prototype radio is being used to validate initial proposed performance requirements for UAS control communications. This presentation will give an overview of the current plans for the prototype radio development.

  9. Study of Calibration of Solar Radio Spectrometers and the quiet-Sun Radio Emission

    CERN Document Server

    Tan, Chengming; Tan, Baolin; Fu, Qijun; Liu, Yuying; Xu, Guirong

    2015-01-01

    This work presents a systematic investigation of the influence of weather conditions on the calibration errors by using Gaussian fitness, least chi-square linear fitness and wavelet transform to analyze the calibration coefficients from observations of the Chinese Solar Broadband Radio Spectrometers (at frequency bands of 1.0-2.0 GHz, 2.6-3.8 GHz, and 5.2-7.6 GHz) during 1997-2007. We found that calibration coefficients are influenced by the local air temperature. Considering the temperature correction, the calibration error will reduce by about $10\\%-20\\%$ at 2800 MHz. Based on the above investigation and the calibration corrections, we further study the radio emission of the quiet-Sun by using an appropriate hybrid model of the quiet-Sun atmosphere. The results indicate that the numerical flux of the hybrid model is much closer to the observation flux than that of other ones.

  10. A Comparison of Radio-loud and Radio-quiet E+A Galaxies

    Science.gov (United States)

    Camacho, Yssavo; Wallack, Nicole; Learis, Anna; Liu, Charles

    2015-01-01

    E+A galaxies are systems undergoing an important evolutionary transition. Their optical spectra show significant numbers of A-type stars in an elliptical galaxy that has little to no star formation (SF). These galaxies have likely experienced a recent starburst (types. We find that the radio-loud and radio-quiet samples exhibit statistically insignificant differences in the optical, near-infrared, and mid-infrared bands. We also compare the two samples on a (J-H) vs. (H-K) color-color diagram. This work was supported by the National Science Foundation via grant AST-1004583 to the CUNY College of Staten Island, and grant AST-1004591 to the American Museum of Natural History.

  11. STUDY OF CALIBRATION OF SOLAR RADIO SPECTROMETERS AND THE QUIET-SUN RADIO EMISSION

    Energy Technology Data Exchange (ETDEWEB)

    Tan, Chengming; Yan, Yihua; Tan, Baolin; Fu, Qijun; Liu, Yuying [Key Laboratory of Solar Activity, National Astronomical Observatories of Chinese Academy of Sciences, Datun Road A20, Chaoyang District, Beijing 100012 (China); Xu, Guirong [Hubei Key Laboratory for Heavy Rain Monitoring and Warning Research, Institute of Heavy Rain, China Meteorological Administration, Wuhan 430205 (China)

    2015-07-20

    This work presents a systematic investigation of the influence of weather conditions on the calibration errors by using Gaussian fitness, least chi-square linear fitness, and wavelet transform to analyze the calibration coefficients from observations of the Chinese Solar Broadband Radio Spectrometers (at frequency bands of 1.0–2.0 GHz, 2.6–3.8 GHz, and 5.2–7.6 GHz) during 1997–2007. We found that calibration coefficients are influenced by the local air temperature. Considering the temperature correction, the calibration error will reduce by about 10%–20% at 2800 MHz. Based on the above investigation and the calibration corrections, we further study the radio emission of the quiet Sun by using an appropriate hybrid model of the quiet-Sun atmosphere. The results indicate that the numerical flux of the hybrid model is much closer to the observation flux than that of other ones.

  12. The age of citizen science: Stimulating future environmental research

    Science.gov (United States)

    Burgess, S. N.

    2010-12-01

    Public awareness of the state of the ocean is growing with issues such as climate change, over-harvesting, marine pollution, coral bleaching, ocean acidification and sea level rise appearing regularly in popular media outlets. Society is also placing greater value on the range of ecosystem services the ocean provides. This increased consciousness of environmental change due to a combination of anthropogenic activities and impacts from climate change offers scientists the opportunity of engaging citizens in environmental research. The term citizen science refers to scientific research carried out by citizens and led by professionals, which involves large scale data collection whilst simultaneously engaging and educating those who participate. Most projects that engage citizen scientists have been specifically designed to provide an educational benefit to the volunteer and benefit the scientific inquiry by collecting extensive data sets over large geographical areas. Engaging the public in environmental science is not a new concept and successful projects (such as the Audobon Christmas Bird Count and Earthwatch) have been running for several decades resulting in hundreds of thousands of people conducting long-term field research in partnership with scientists based at universities worldwide. The realm of citizen science projects is continually expanding, with public engagement options ranging from science online; to backyard afternoon studies; to fully immersive experiential learning projects running for weeks at a time. Some organisations, such as Earthwatch also work in partnership with private industry; giving scientists access to more funding opportunities than those avenues traditionally available. These scientist -industry partnerships provide mutual benefits as the results of research projects in environments such as coastal ecosystems feed directly back into business risk strategies; for example mitigating shoreline erosion, storm surges, over fishing and

  13. THE AUGER ENGINEERING RADIO ARRAY

    Directory of Open Access Journals (Sweden)

    Klaus Weidenhaupt

    2013-12-01

    Full Text Available The Auger Engineering Radio Array currently measures MHz radio emission from extensive air showers induced by high energy cosmic rays with 24 self-triggered radio detector stations. Its unique site, embedded into the baseline detectors and extensions of the Pierre Auger Observatory, allows to study air showers in great detail and to calibrate the radio emission. In its final stage AERA will expand to an area of approximately 20km2 to explore the feasibility of the radio-detection technique for future cosmic-ray detectors. The concept and hardware design of AERA as well as strategies to enable self-triggered radio detection are presented. Radio emission mechanisms are discussed based on polarization analysis of the first AERA data.

  14. Radio observations of Planck clusters

    CERN Document Server

    Kale, Ruta

    2012-01-01

    Recently, a number of new galaxy clusters have been detected by the ESA-Planck satellite, the South Pole Telescope and the Atacama Cosmology Telescope using the Sunyaev-Zeldovich effect. Several of the newly detected clusters are massive, merging systems with disturbed morphology in the X-ray surface brightness. Diffuse radio sources in clusters, called giant radio halos and relics, are direct probes of cosmic rays and magnetic fields in the intra-cluster medium. These radio sources are found to occur mainly in massive merging clusters. Thus, the new SZ-discovered clusters are good candidates to search for new radio halos and relics. We have initiated radio observations of the clusters detected by Planck with the Giant Metrewave Radio Telescope. These observations have already led to the detection of a radio halo in PLCKG171.9-40.7, the first giant halo discovered in one of the new Planck clusters.

  15. Thermal and Nonthermal Radio Galaxies

    CERN Document Server

    Antonucci, Robert

    2011-01-01

    Radio galaxies were discovered and mapped in the 1950s. The optical spectra showed little or no nuclear continuum light. Some also revealed powerful high ionization emission lines, while others showed at most weak low-ionization emission lines. Quasars were found in the 1960s, and their spectra were dominated by powerful continuum radiation which was subsequently identified with optically thick thermal radiation from copious accretion flows, as well as high ionization narrow emission lines, and powerful broad permitted lines. By the 1980s, data from optical polarization and statistics of the radio properties required that many radio galaxies contain hidden quasar nuclei, hidden from the line of sight by dusty, roughly toroidal gas distributions. The radio galaxies with hidden quasars are referred to as "thermal." Do all radio galaxies have powerful hidden quasars? We now know the answer using arguments based on radio, infrared, optical and X-ray properties. Near the top of the radio luminosity function, for F...

  16. The How of Successful Citizen Advisory Committee Operation. A Research and Development Project: Citizen Participation in Policy Making for Public Schools in Illinois.

    Science.gov (United States)

    Phipps, Lloyd J.; Knell, Kenneth

    As a means of encouraging the formation of school-sponsored, citizen advisory committees, the Illinois Citizens Education Council embarked on a 3-year research and development project. This publication describes this project and thereby serves as a guide for organizing and using citizens' education advisory committees. Specific objectives of the…

  17. Distributed Radio Interferometric Calibration

    CERN Document Server

    Yatawatta, Sarod

    2015-01-01

    Increasing data volumes delivered by a new generation of radio interferometers require computationally efficient and robust calibration algorithms. In this paper, we propose distributed calibration as a way of improving both computational cost as well as robustness in calibration. We exploit the data parallelism across frequency that is inherent in radio astronomical observations that are recorded as multiple channels at different frequencies. Moreover, we also exploit the smoothness of the variation of calibration parameters across frequency. Data parallelism enables us to distribute the computing load across a network of compute agents. Smoothness in frequency enables us reformulate calibration as a consensus optimization problem. With this formulation, we enable flow of information between compute agents calibrating data at different frequencies, without actually passing the data, and thereby improving robustness. We present simulation results to show the feasibility as well as the advantages of distribute...

  18. Searches for radio transients

    CERN Document Server

    Bhat, N D R

    2011-01-01

    Exploration of the transient Universe is an exciting and fast-emerging area within radio astronomy. Known transient phenomena range in time scales from sub-nanoseconds to years or longer, thus spanning a huge range in time domain and hinting a rich diversity in their underlying physical processes. Transient phenomena are likely locations of explosive or dynamic events and they offer tremendous potential to uncover new physics and astrophysics. A number of upcoming next-generation radio facilities and recent advances in computing and instrumentation have provided a much needed impetus for this field which has remained a relatively uncharted territory for the past several decades. In this paper we focus mainly on the class of phenomena that occur on very short time scales (i.e. from $\\sim$ milliseconds to $\\sim$ nanoseconds), known as {\\it fast transients}, the detections of which involve considerable signal processing and data management challenges, given the high time and frequency resolutions required in the...

  19. 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.

  20. Tracing low-mass galaxy clusters with radio relics: the discovery of Abell 3527-bis

    CERN Document Server

    de Gasperin, F; Ridl, J; Salvato, M; van Weeren, R; Bonafede, A; Greiner, J; Cassano, R; Bruggen, M

    2016-01-01

    Galaxy clusters undergo mergers that can generate extended radio sources called radio relics. Radio relics are the consequence of merger-induced shocks that propagate in the intra cluster medium (ICM). In this paper we analyse the radio, optical and X-ray data from a candidate galaxy cluster that has been selected from the radio emission coming from a candidate radio relic detected in NRAO VLA Sky Survey (NVSS). Our aim is to clarify the nature of this source and prove that under certain conditions radio emission from radio relics can be used to trace relatively low-mass galaxy clusters. We have observed the candidate galaxy cluster with the Giant Meterwave Radio Telescope (GMRT) at three different frequencies. These datasets have been analysed together with archival data from ROSAT in the X-ray and with archival data from the Gamma-Ray Burst Optical/Near-Infrared Detector (GROND) telescope in four different optical bands. We confirm the presence of a 1 Mpc long radio relic located in the outskirts of a previ...

  1. Radio frequency ion source

    CERN Document Server

    Shen Guan Ren; Gao Fu; LiuNaiYi

    2001-01-01

    The study on Radio Frequency Ion Source is mainly introduced, which is used for CIAE 600kV ns Pulse Neutron Generator; and obtained result is also presented. The RF ion source consists of a diameter phi 25 mm, length 200 mm, coefficient of expansion =3.5 mA, beam current on target >=1.5 mA, beam spot =100 h.

  2. Citizen Preparedness Campaign: Information Campaigns Increasing Citizen Preparedness to Support Creating a `Culture of Preparedness’

    Science.gov (United States)

    2007-03-01

    objectives, and other aspects. For instance, in 1989, the MADD campaign targeted teenagers and youths trying to reduce underage drinking. In 1996...Partners for this portion of the campaign include NPR; country, rock, rap , alternative and Spanish stations; other talk radio shows; Ad Council...advertisements, play music , show a short film called First Look about what is going on in Hollywood and finally show commercials prior to the feature

  3. Broad-Band Spectral Indices Variability of BL Lacertae by Wavelet Method

    Indian Academy of Sciences (India)

    Hao-Jing Zhang; Jing-Ming Bai; Yu-Ying Bao; Xiong Zhang

    2014-09-01

    BL Lacertae is one of the famous AGN that shows convincing evidence to support periodic variability. We compile R-band data and radio 22 GHz database from the available literature to build the light curves and to calculate broad-band spectral indices. This paper employs the wavelet periodic estimation method. The analysis results indicate that the most possible period is 7.02–7.36 yr in the selected wave-bands. The broad-band spectral indices have a possible period of 4.11 yr as a half value in selected wave-bands. The results confirm that the variability period in the radio 22 GHz is in agreement with the optical R band of about 7.01 yr, as also mentioned in other literatures.

  4. The V in VGI: Citizens or Civic Data Sources

    Directory of Open Access Journals (Sweden)

    Suthee Sangiambut

    2016-07-01

    Full Text Available Volunteered geographic information (VGI, delivered via mobile and web apps, offers new potentials for civic engagement. If framed in the context of open, transparent and accountable governance then presumably VGI should advance dialogue and consultation between citizen and government. If governments perceive citizens as consumers of services then arguably such democratic intent elide when municipalities use VGI. Our empirical research shows how assumptions embedded in VGI drive the interaction between citizens and government. We created a typology that operationalises VGI as a potential act of citizenship and an instance of consumption. We then selected civic apps from Canadian cities that appeared to invoke these VGI types. We conducted interviews with developers of the apps; they were from government, private sector, and civil society. Results from qualitative semi-structured interviews indicate a blurring of consumer and citizen-centric orientations among respondents, which depended on motivations for data use, engagement and communication objectives, and sector of the respondent. Citizen engagement, an analogue for citizenship, was interpreted multiple ways. Overall, we found that government and developers may increase choice by creating consumer-friendly apps but this does not ensure VGI offers an act of civic participation. The burden is placed on the contributor to make it so. Apps and VGI could potentially further a data-driven and neoliberal government. Planners should be mindful of the dominance of a consumer-centric view even as they assume VGI invariably improves democratic participation.

  5. Initial Results Obtained with the First TWIN VLBI Radio Telescope at the Geodetic Observatory Wettzell.

    Science.gov (United States)

    Schüler, Torben; Kronschnabl, Gerhard; Plötz, Christian; Neidhardt, Alexander; Bertarini, Alessandra; Bernhart, Simone; la Porta, Laura; Halsig, Sebastian; Nothnagel, Axel

    2015-07-30

    Geodetic Very Long Baseline Interferometry (VLBI) uses radio telescopes as sensor networks to determine Earth orientation parameters and baseline vectors between the telescopes. The TWIN Telescope Wettzell 1 (TTW1), the first of the new 13.2 m diameter telescope pair at the Geodetic Observatory Wettzell, Germany, is currently in its commissioning phase. The technology behind this radio telescope including the receiving system and the tri-band feed horn is depicted. Since VLBI telescopes must operate at least in pairs, the existing 20 m diameter Radio Telescope Wettzell (RTW) is used together with TTW1 for practical tests. In addition, selected long baseline setups are investigated. Correlation results portraying the data quality achieved during first initial experiments are discussed. Finally, the local 123 m baseline between the old RTW telescope and the new TTW1 is analyzed and compared with an existing high-precision local survey. Our initial results are very satisfactory for X-band group delays featuring a 3D distance agreement between VLBI data analysis and local ties of 1 to 2 mm in the majority of the experiments. However, S-band data, which suffer much from local radio interference due to WiFi and mobile communications, are about 10 times less precise than X-band data and require further analysis, but evidence is provided that S-band data are well-usable over long baselines where local radio interference patterns decorrelate.

  6. Initial Results Obtained with the First TWIN VLBI Radio Telescope at the Geodetic Observatory Wettzell

    Directory of Open Access Journals (Sweden)

    Torben Schüler

    2015-07-01

    Full Text Available Geodetic Very Long Baseline Interferometry (VLBI uses radio telescopes as sensor networks to determine Earth orientation parameters and baseline vectors between the telescopes. The TWIN Telescope Wettzell 1 (TTW1, the first of the new 13.2 m diameter telescope pair at the Geodetic Observatory Wettzell, Germany, is currently in its commissioning phase. The technology behind this radio telescope including the receiving system and the tri-band feed horn is depicted. Since VLBI telescopes must operate at least in pairs, the existing 20 m diameter Radio Telescope Wettzell (RTW is used together with TTW1 for practical tests. In addition, selected long baseline setups are investigated. Correlation results portraying the data quality achieved during first initial experiments are discussed. Finally, the local 123 m baseline between the old RTW telescope and the new TTW1 is analyzed and compared with an existing high-precision local survey. Our initial results are very satisfactory for X-band group delays featuring a 3D distance agreement between VLBI data analysis and local ties of 1 to 2 mm in the majority of the experiments. However, S-band data, which suffer much from local radio interference due to WiFi and mobile communications, are about 10 times less precise than X-band data and require further analysis, but evidence is provided that S-band data are well-usable over long baselines where local radio interference patterns decorrelate.

  7. Are Homologous Radio Bursts Driven by Solar Post-Flare Loops?

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Three particularly complex radio bursts (2001 October 19, 2001 April 10 and 2003 October 26) obtained with the spectrometers (0.65-7.6 GHz) at the National Astronomical Observatories, Chinese Academy of Sciences (NAOC, Beijing and Yunnan) and other instruments (NoRH, TRACE and SXT) are presented. They each have two groups of peaks occurring in different frequency ranges (broad-band microwave and narrow-band decimeter wavelengths). We stress that the second group of burst peaks that occurred in the late phase of the flares and associated with post-flare loops may be homologous radio bursts. We think that they are driven by the post-flare loops. In contrast to the time profiles of the radio bursts and the images of coronal magnetic polarities, we are able to find that the three events are caused by the active regions including main single-bipole magnetic structures, which are associated with multipole magnetic structures during the flare evolutions. In particular, we point out that the later decimetric radio bursts are possibly the radio counterparts of the homologous flares (called "homologous radio bursts" by us), which are also driven by the single-bipole magnetic structures. By examining the evolutions of the magnetic polarities of sources (17 GHz),we could presume that the drivers of the homologous radio bursts are new and/or recurring appearances/disappearances of the magnetic polarities of radio sources, and that the triggers are the magnetic reconnections of single-bipole configurations.

  8. ATCA observations of the MACS-Planck Radio Halo Cluster Project - I. New detection of a radio halo in PLCK G285.0-23.7

    CERN Document Server

    Aviles, Gerardo Martinez; Johnston-Hollitt, Melanie; Pratley, Luke; Macario, Giulia; Venturi, Tiziana; Brunetti, Gianfranco; Cassano, Rossella; Dallacasa, Daniele; Intema, Huib; Giacintucci, Simona; Hurier, Guillaume; Aghanim, Nabila; Douspis, Marian; Langer, Mathieu

    2016-01-01

    We investigate the possible presence of diffuse radio emission in the intermediate redshift, massive cluster PLCK G285.0-23.7 (z=0.39, M_500 = 8.39 x 10^(14) M_Sun). Our 16cm-band ATCA observations of PLCK G285.0-23.7 allow us to reach a rms noise level of ~11 microJy/beam on the wide-band (1.1-3.1 GHz), full-resolution (~5 arcsec) image of the cluster, making it one of the deepest ATCA images yet published. We also re-image visibilities at lower resolution in order to achieve a better sensitivity to low-surface-brightness extended radio sources. We detect one of the lowest luminosity radio halos known at z>0.35, characterised by a slight offset from the well-studied 1.4 GHz radio power vs. cluster mass correlation. Similarly to most known radio-loud clusters (i.e. those hosting diffuse non-thermal sources), PLCK G285.0-23.7 has a disturbed dynamical state. Our analysis reveals a similarly elongated X-ray and radio morphology. While the size of the radio halo in PLCK G285.0-23.7 is smaller than lower redshift...

  9. Observations of Supernova Remnants with the Sardinia Radio Telescope

    CERN Document Server

    Egron, E; Loru, S; Iacolina, M N; Marongiu, M; Righini, S; Mulas, S; Murtas, G; Bachetti, M; Concu, R; Melis, A; Trois, A; Ricci, R; Pilia, M

    2016-01-01

    In the frame of the Astronomical Validation activities for the 64m Sardinia Radio Telescope, we performed 5-22 GHz imaging observations of the complex-morphology supernova remnants (SNRs) W44 and IC443. We adopted innovative observing and mapping techniques providing unprecedented accuracy for single-dish imaging of SNRs at these frequencies, revealing morphological details typically available only at lower frequencies through interferometry observations. High-frequency studies of SNRs in the radio range are useful to better characterize the spatially-resolved spectra and the physical parameters of different regions of the SNRs interacting with the ISM. Furthermore, synchrotron-emitting electrons in the high-frequency radio band are also responsible for the observed high-energy phenomenology as -e.g.- Inverse Compton and bremsstrahlung emission components observed in gamma-rays, to be disentangled from hadron emission contribution (providing constraints on the origin of cosmic rays).

  10. Radio Bursts with Extragalactic Spectral Characteristics Show Terrestrial Origins

    CERN Document Server

    Burke-Spolaor, Sarah; Ekers, Ronald; Macquart, Jean-Pierre; Crawford, Fronefield

    2010-01-01

    Three years ago, the report of a solitary radio burst was thought to be the first discovery of a rare, impulsive event of unknown extragalactic origin (Lorimer et al. 2007). The extragalactic interpretation was based on the swept-frequency nature of the event, which followed the dispersive delay expected from an extragalactic pulse. We report here on the detection of 16 pulses, the bulk of which exhibit a frequency sweep with a shape and magnitude resembling the Lorimer Burst. These new events were detected in a sidelobe of the Parkes Telescope and are of clearly terrestrial origin, with properties unlike any known sources of terrestrial broad-band radio emission. The new detections cast doubt on the extragalactic interpretation of the original burst, and call for further sophistication in radio-pulse survey techniques to identify the origin of the anomalous terrestrial signals and definitively distinguish future extragalactic pulse detections from local signals. The ambiguous origin of these seemingly disper...

  11. Addressing Carrier Aggregation with Narrow-band Tunable Antennas

    DEFF Research Database (Denmark)

    Barrio, Samantha Caporal Del; Morris, Art; Pedersen, Gert F.

    2016-01-01

    Enhancing the operating bandwidth of antennas is particularly challenging when the antenna is confined in a very restricted volume, as is the case for mobile phones. However, increasing the bandwidth provides higher data rates to the users. Consequently, the carrier aggregation technology has been...... standardized. This paper proposes an antenna design that can address the bandwidth issue of new radio frequency standards, while coping with carrier aggregation requirements. Specifically, the paper presents a dual-antenna system, where each antenna exhibits a dual resonance. The low-bands of the radio...

  12. Compact radio cores in radio-quiet AGNs

    CERN Document Server

    Maini, Alessandro; Norris, Ray P; Giovannini, Gabriele; Spitler, Lee R

    2016-01-01

    The mechanism of radio emission in radio-quiet (RQ) active galactic nuclei (AGN) is still debated and might arise from the central AGN, from star formation activity in the host, or from either of these sources. A direct detection of compact and bright radio cores embedded in sources that are classified as RQ can unambiguously determine whether a central AGN significantly contributes to the radio emission. We search for compact, high-surface-brightness radio cores in RQ AGNs that are caused unambiguously by AGN activity. We used the Australian Long Baseline Array to search for compact radio cores in four RQ AGNs located in the Extended Chandra Deep Field South (ECDFS). We also targeted four radio-loud (RL) AGNs as a control sample. We detected compact and bright radio cores in two AGNs that are classified as RQ and in one that is classified as RL. Two RL AGNs were not imaged because the quality of the observations was too poor. We report on a first direct evidence of radio cores in RQ AGNs at cosmological reds...

  13. Putting citizens at the heart of food system governance

    Energy Technology Data Exchange (ETDEWEB)

    Pimbert, Michel

    2012-05-15

    Establishing inclusive governance of food systems — where farmers and other citizens play an active role in designing and implementing food and agricultural policies — is not just a matter of equity or social justice. Evidence shows that it can also lead to more sustainable livelihoods and environments. And yet, across the world, food system governance is marked by exclusionary processes that favour the values and interests of more powerful corporations, investors, big farmers and large research institutes. How can we tip the balance and amplify the voice and influence of marginalised citizens in setting the food and agricultural policies that affect them? Research points to six tried and tested ways that, when combined, can empower citizens in the governance of food systems.

  14. Bridging Identity Gaps : Supporting Identity Performance in Citizen Service Encounters

    DEFF Research Database (Denmark)

    Borchorst, Nikolaj Gandrup; McPhail, Brenda; Smith, Karen Louise;

    2012-01-01

    administrative processes and the quality and swiftness of the service they receive. As we bring to light in this paper, this “fitting in” with rigid bureaucratic procedures and IT systems interestingly requires a substantial collaborative effort between the receiver(s) of the service and a complex constellation...... of surrounding stakeholders and intermediaries. This collaboration and the performing of multiple identities raises challenges for the design of e-government systems aimed at supporting physical and digital citizen service provision, as well as issues regarding privacy, citizenship, and public service quality......This paper explores in situ citizen service encounters in government offices. Drawing upon ethnographically informed fieldwork in Canada and Denmark, we discuss the challenges to supporting citizens in constructing and performing identities in public service settings. Our data suggests...

  15. Attitudes of Brazilian citizens towards pig production systems

    DEFF Research Database (Denmark)

    de Barcellos, Marcia Dutra; Kügler, Jens Oliver; Saab, Maria Stella Melo

    The objective of this study is to map Brazilian citizen attitudes towards pig meat production systems and to investigate whether these attitudes associate with pork and pork product consumption. A conjoint experiment was carried out with empirical data collected from 475 respondents interviewed...... in southern and central-western states of Brazil. The experiment was based on the following pig farming characteristics: farm size, floor type, efforts to protect soil, air and water, fat content, and pork quality. The results of the conjoint analysis were used for a subsequent cluster analysis in order...... were identified as "average", "environmental conscious" and "tradition and animal welfare-oriented" citizens. Although attitudes towards environment and nature were indeed related to citizens' specific attitudes towards pig farming at the cluster level, the relationship between citizenship...

  16. Science Learning via Participation in Online Citizen Science

    CERN Document Server

    Masters, Karen; Cox, Joe; Simmons, Brooke; Lintott, Chris; Graham, Gary; Greenhill, Anita; Holmes, Kate

    2016-01-01

    We investigate the development of scientific content knowledge of volunteers participating in online citizen science projects in the Zooniverse (www.zooniverse.org), including the astronomy projects Galaxy Zoo (www.galaxyzoo.org) and Planet Hunters (www.planethunters.org). We use econometric methods to test how measures of project participation relate to success in a science quiz, controlling for factors known to correlate with scientific knowledge. Citizen scientists believe they are learning about both the content and processes of science through their participation. Won't don't directly test the latter, but we find evidence to support the former - that more actively engaged participants perform better in a project-specific science knowledge quiz, even after controlling for their general science knowledge. We interpret this as evidence of learning of science content inspired by participation in online citizen science.

  17. Elementary School Children Contribute to Environmental Research as Citizen Scientists.

    Directory of Open Access Journals (Sweden)

    Victoria L Miczajka

    Full Text Available Research benefits increasingly from valuable contributions by citizen scientists. Mostly, participating adults investigate specific species, ecosystems or phenology to address conservation issues, but ecosystem functions supporting ecosystem health are rarely addressed and other demographic groups rarely involved. As part of a project investigating seed predation and dispersal as ecosystem functions along an urban-rural gradient, we tested whether elementary school children can contribute to the project as citizen scientists. Specifically, we compared data estimating vegetation cover, measuring vegetation height and counting seeds from a seed removal experiment, that were collected by children and scientists in schoolyards. Children counted seeds similarly to scientists but under- or overestimated vegetation cover and measured different heights. We conclude that children can be involved as citizen scientists in research projects according to their skill level. However, more sophisticated tasks require specific training to become familiarized with scientific experiments and the development of needed skills and methods.

  18. Optimal Medium Access Protocols for Cognitive Radio Networks

    CERN Document Server

    Lai, Lifeng; Jiang, Hai; Poor, H Vincent

    2008-01-01

    This paper focuses on the design of medium access control protocols for cognitive radio networks. The scenario in which a single cognitive user wishes to opportunistically exploit the availability of empty frequency bands within parts of the radio spectrum having multiple bands is first considered. In this scenario, the availability probability of each channel is unknown a priori to the cognitive user. Hence efficient medium access strategies must strike a balance between exploring (learning) the availability probability of the channels and exploiting the knowledge of the availability probability identified thus far. For this scenario, an optimal medium access strategy is derived and its underlying recursive structure is illustrated via examples. To avoid the prohibitive computational complexity of this optimal strategy, a low complexity asymptotically optimal strategy is developed. Next, the multi-cognitive user scenario is considered and low complexity medium access protocols, which strike an optimal balanc...

  19. X-ray Radio Correlation In Black Hole Sources

    CERN Document Server

    Rao, A R

    2006-01-01

    We examine the X-ray - radio correlation in Galactic black hole sources. We highlight some of the results which extend the flux-flux relations to sources with very high accretion rates. Some of the recent results indicate that the synchrotron process is unlikely to be the mechanism responsible for the X-ray emission, particularly at high accretion rates. We present a truncated accretion disk scenario and argue that accretion rate and accretion disk geometry ultimately act as a driver of the X-ray - radio correlation. We stress the importance of wide-band X-ray spectral measurements to understand the disk-jet connection and briefly outline some attempts made in the Indian context to build instruments for wide-band X-ray spectroscopy.

  20. ZEBRAFISH CHROMOSOME-BANDING

    NARCIS (Netherlands)

    PIJNACKER, LP; FERWERDA, MA

    1995-01-01

    Banding techniques were carried out on metaphase chromosomes of zebrafish (Danio rerio) embryos. The karyotypes with the longest chromosomes consist of 12 metacentrics, 26 submetacentrics, and 12 subtelocentrics (2n = 50). All centromeres are C-band positive. Eight chromosomes have a pericentric C-b