Articles de revues : « Radio set »

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van Woerkom, Ethan. « Astronomy set for radio burst revolution ». Physics World 36, n^o 5 (1 mai 2023) : 14. http://dx.doi.org/10.1088/2058-7058/36/05/17.

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Tortzen, Anne. « Unge, musik og radio ». MedieKultur : Journal of media and communication research 8, n^o 18 (29 août 1992) : 12. http://dx.doi.org/10.7146/mediekultur.v8i18.926.

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Mens unges brug af billedmedier har fået megen opmærksomhed de senere år, er radioen blevet overset. Radioen er for de unge først og fremmest et musikmedie og er som sådan et af de vigtigste medier i de unges liv. Danmarks Radios Medieforsknings afdeling har gennem en kvalitativ analyse af de 16-19 åriges brug af radio, set i sammenhæng med uddannelse og musiksmag. For de unge bærer radioen både musikken og andre kulturelle signaler: Programværternes roller, præ- sentationsformerne osv.. Derfor kan musik og radio betragtes som en vigtig del af det kulturelle rum, hvor unge bearbejder hverdagslivets erfaringer og udtrykker deres identitet.

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Bhutto, Zuhaibuddin, Jun-Hyuk Park et Wonyong Yoon. « Characterizing Multi-radio Energy Consumption in Cellular/Wi-Fi Smartphones ». International Journal of Electrical and Computer Engineering (IJECE) 6, n^o 6 (1 décembre 2016) : 2920. http://dx.doi.org/10.11591/ijece.v6i6.11916.

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<p>Cellular networks evolved to meet the ever increasing traffic demand by way of offloading mobile traffic to Wi-Fi network elements. Exploiting multi-radio interfaces on a smartphone has recently been examined with regards to heterogeneous bandwidth aggregation and radio switching. However, how a smartphone consumes its energy in driving cellular and Wi-Fi multi-radio interfaces, is not well understood. In this paper, we revealed the energy consumption behavior of 3G cellular and Wi-Fi multi-radio operations of a smartphone. We modified smartphone’s firmware to enable multi-radios operations simultaneously and we performed extensive measurements of multi-radio energy consumption in a real commercial network. From the measured data set, we established a realistic multi-radio energy consumption model and it gave 98% stability from the derived coefficients.</p>

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Bhutto, Zuhaibuddin, Jun-Hyuk Park et Wonyong Yoon. « Characterizing Multi-radio Energy Consumption in Cellular/Wi-Fi Smartphones ». International Journal of Electrical and Computer Engineering (IJECE) 6, n^o 6 (1 décembre 2016) : 2920. http://dx.doi.org/10.11591/ijece.v6i6.pp2920-2930.

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<p>Cellular networks evolved to meet the ever increasing traffic demand by way of offloading mobile traffic to Wi-Fi network elements. Exploiting multi-radio interfaces on a smartphone has recently been examined with regards to heterogeneous bandwidth aggregation and radio switching. However, how a smartphone consumes its energy in driving cellular and Wi-Fi multi-radio interfaces, is not well understood. In this paper, we revealed the energy consumption behavior of 3G cellular and Wi-Fi multi-radio operations of a smartphone. We modified smartphone’s firmware to enable multi-radios operations simultaneously and we performed extensive measurements of multi-radio energy consumption in a real commercial network. From the measured data set, we established a realistic multi-radio energy consumption model and it gave 98% stability from the derived coefficients.</p>

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Saha, Laxman, et Pratima Panigrahi. « A new graph radio k-coloring algorithm ». Discrete Mathematics, Algorithms and Applications 11, n^o 01 (février 2019) : 1950005. http://dx.doi.org/10.1142/s1793830919500058.

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Due to the rapid growth in the use of wireless communication services and the corresponding scarcity and the high cost of radio spectrum bandwidth, Channel assignment problem (CAP) is becoming highly important. Radio [Formula: see text]-coloring of graphs is a variation of CAP. For a positive integer [Formula: see text], a radio [Formula: see text]-coloring of a simple connected graph [Formula: see text] is a mapping [Formula: see text] from the vertex set [Formula: see text] to the set [Formula: see text] of non-negative integers such that [Formula: see text] for each pair of distinct vertices [Formula: see text] and [Formula: see text] of [Formula: see text], where [Formula: see text] is the distance between [Formula: see text] and [Formula: see text] in [Formula: see text]. The span of a radio [Formula: see text]-coloring [Formula: see text], denoted by [Formula: see text], is defined as [Formula: see text] and the radio[Formula: see text]-chromatic number of [Formula: see text], denoted by [Formula: see text], is [Formula: see text] where the minimum is taken over all radio [Formula: see text]-coloring of [Formula: see text]. In this paper, we present two radio [Formula: see text]-coloring algorithms for general graphs which will produce radio [Formula: see text]-colorings with their spans. For an [Formula: see text]-vertex simple connected graph the time complexity of the both algorithm is of [Formula: see text]. Implementing these algorithms we get the exact value of [Formula: see text] for several graphs (for example, [Formula: see text], [Formula: see text], [Formula: see text], some circulant graph etc.) and many values of [Formula: see text], especially for [Formula: see text].

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Mamidi, Suman, Emily Blem, Michael J. Schulte, John Glossner, Daniel Iancu, Andrei Iancu, Mayan Moudgill et Sanjay Jinturkar. « Instruction set extensions for software defined radio ». Microprocessors and Microsystems 33, n^o 4 (juin 2009) : 260–72. http://dx.doi.org/10.1016/j.micpro.2009.02.005.

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Asy'ari, Nur Aini Shofiya, et Nurhana Marantika. « Listenership Sebagai Evaluasi Penerapan Konvergensi Radio ». Jurnal Studi Komunikasi (Indonesian Journal of Communications Studies) 4, n^o 1 (5 mars 2020) : 203. http://dx.doi.org/10.25139/jsk.v4i1.1934.

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Previous researches on radio convergence showed that various radio stations in Ponorogo have implemented convergence by using new media platforms, such as, radio and video streaming, Youtube, and social media. However, evaluations on radio convergence has never been done before. Therefore, this research was conducted to study the effect of convergence to the listenership as well as to evaluate the implementation of radio-convergence in Ponorogo radio stations from April to July 2019. Using a survey method, the researchers administered a set of questionnaires to 267 respondents in Ponorogo to find out the listenership trends in Ponorogo community on its radio and other convergence platforms. The results of the study showed that the convergence implemented by the radios failed to raise awareness and number of radio listeners. Low awareness affects the community’s media habit. It was apparent in the fact that 84% of the respondents preferred conventional (analog) radio to a convergence platform. The results of this study also showed that convergence was unable to foster community involvement with radio. In other words, the radio was not the primary choice of the Ponorogo community in accessing information or entertainment.

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Maiden, Martha E., et W. A. Christiansen. « Hercules A : a precessing cannon ? » Canadian Journal of Physics 64, n^o 4 (1 avril 1986) : 490–94. http://dx.doi.org/10.1139/p86-092.

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Hercules A is an unusual radio source in that its structure is dominated (most specifically on the western side of the source) by an undulating chain of discrete "rings" of radio emission, whose individual radii increase progressively with distance from the nuclear core while their apparent separation decreases. In the theoretical model presented here, these interesting radio features are presumed to be due to emission from a discrete set of ram-pressure confined plasmoids that have been periodically ejected by a precessing nuclear engine. The predicted deceleration and expansion of these ram-pressure confined plasmoids provides an excellent fit to the observed spacing and radii of the radio rings observed on the western side of Hercules A. Furthermore, a satisfactory fit to the morphology of the undulating eastern jet can also be achieved using this discrete ejection model, providing the eastward ejections alternate with the westward ejections, thus implying a form of flip-flop behavior for this particular source.

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Vaidya, S. K., et D. D. Bantva. « Radio Number for Total Graph of Paths ». ISRN Combinatorics 2013 (13 janvier 2013) : 1–5. http://dx.doi.org/10.1155/2013/326038.

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A radio labeling of a graph is a function from the vertex set to the set of nonnegative integers such that , where and are diameter and distance between and in graph , respectively. The radio number of is the smallest number such that has radio labeling with . We investigate radio number for total graph of paths.

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O'Donoghue, Aileen A., Jean A. Eilek et Frazer N. Owen. « Observations of Straight-angle Tailed Radio Galaxies in Rich Clusters of Galaxies ». Symposium - International Astronomical Union 175 (1996) : 349–50. http://dx.doi.org/10.1017/s0074180900081067.

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We have begun VLA observations of straight-angle tailed radio sources (SATs) at 1.5 and 4.8 GHz (L and C band) to achieve one arcsecond resolution at each frequency. This will provide a SAT data set similar to the O'Donoghue, Owen, and Eilek (1990) WAT data set with both total intensity and spectral index information. We will use these data to examine morphological and dynamical properties of straight-tailed radio sources in clusters of galaxies.

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Charl Durand, Charl Durand. « Game, set and message ». Communicare : Journal for Communication Studies in Africa 20, n^o 1 (31 octobre 2022) : 67–73. http://dx.doi.org/10.36615/jcsa.v20i1.1869.

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Sport is just not cricket any more. Seems like just yesterday the only way weJohannesburg folk could follow a nail-biting international rugby test happening atNewlands in Cape Town was by listening to Gerhard Viviers' commentary on Afrikaansradio. I remember my grandfather sitting on the stoep, a map of the playing fielddrawn on a large sheet of paper on his lap, plotting team moves, attacks, defences andscores, as Gerhard's staccato commentary poured through the speakers of an old Grundigmedium wave receiver next to him; definitely a case of what Marshall Mcluhan wouldcall 'a very cool medium'.In the days before mass media, the sports message sent to those absent from theaction on the field contained little else of fact other than a score, and a winner, andthe message reached the receiver a day, a week or a month later. Messages then graduallyexpanded to include match details and perhaps a grainy photograph or two as newspapersstarted reporting on sport. Radio revolutionised sport in that it provided the impetusfor the massification of sport as teams and individuals developed followings, and theconcept of 'the fan' was born. Radio truly took sports matches beyond the stadiumgates for the first time.

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da Silva, Fabrício A. B., David F. C. Moura et Juraci F. Galdino. « Classes of Attacks for Tactical Software Defined Radios ». International Journal of Embedded and Real-Time Communication Systems 3, n^o 4 (octobre 2012) : 57–82. http://dx.doi.org/10.4018/jertcs.2012100104.

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This survey presents a classification of attacks that Software Communications Architecture (SCA) compliant Software Defined Radios (SDR) can suffer. This paper also discusses how attack mitigation strategies can impact the development of a SCA-compliant software infrastructure and identifies several research directions related to SDR security. The SCA standard was originally proposed by the Joint Tactical Radio System program (JTRS), which is a program for the development of military tactical radios sponsored by the US Department of Defense. The classification presented in this paper is based on attack results on the radio set, which can also be associated with the adversary’s objectives when planning an intrusion. The identification of classes of attacks on a radio, along with the associated threats and vulnerabilities, is the first step in engineering a secure SDR system. It precedes the identification of security requirements and the development of security mechanisms. Therefore, the identification of classes of attacks is a necessary step for the definition of realistic and relevant security requirements.

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Kellermann, Walter. « Mobile radio set comprising a speech processing arrangement ». Journal of the Acoustical Society of America 102, n^o 5 (1997) : 2481. http://dx.doi.org/10.1121/1.420373.

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Yu, Jiguo, Wenchao Li, Xiuzhen Cheng, Mohammed Atiquzzaman, Hua Wang et Li Feng. « Connected dominating set construction in cognitive radio networks ». Personal and Ubiquitous Computing 20, n^o 5 (13 août 2016) : 757–69. http://dx.doi.org/10.1007/s00779-016-0944-6.

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Benghabrit, Nawel, et Mejdi Kaddour. « Optimizing the Capacity of Cognitive Radio Networks with Power Control and Variable Spectrum Allocation ». Transport and Telecommunication Journal 19, n^o 2 (1 juin 2018) : 128–39. http://dx.doi.org/10.2478/ttj-2018-0011.

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Abstract Cognitive Radio Networks (CRN) were introduced as a means to more efficiently reuse the licensed radio frequency spectrum. One of their salient features is the ability of unlicensed nodes to dynamically adapt their radio parameters according to their needs. This paper investigates the resource allocation problem in CRN by jointly considering power control and bandwidth for a set of secondary users (SU) transmitting simultaneously with a set of licensed users (PU), which transmissions must remain unaltered. The proposed allocation scheme is based on a Genetic Algorithm (GA) where the chromosome's genes represent the reconfigurable interface radio parameters, by defining genetic operations the GA is empowered to find a set of radio parameters that maximize the overall network capacity and under the physical interference model enforced to the transmissions of both PU’s and SU’s. The numerical results illustrate the prominent effect of adjusting jointly multiple radio parameters on the network capacity.

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Bista, Janardan. « Effectiveness of Multilingual Broadcasting : A Case Study of Radio Nepal ». Historical Journal 14, n^o 2 (4 octobre 2023) : 65–78. http://dx.doi.org/10.3126/hj.v14i2.59062.

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Radio Nepal, as the pioneering radio broadcaster of the country, has played a crucial role in serving its listeners for over seven decades. In the earlier years, it was the sole medium of information, education, and entertainment, particularly for rural communities, before the advent of television and FM radios. As a national broadcaster, Radio Nepal has assumed significant national duties and responsibilities that set it apart from other media outlets. In response to the evolving socio-political landscape, Radio Nepal has bolstered its multilingual or inclusive broadcasting by incorporating more native languages into its programming. Currently, it broadcasts news and programs in 21 different languages, in addition to Nepali, aiming to address the linguistic diversity of the nation. This research aims to fill this knowledge gap and assess the impact of Radio Nepal's inclusive broadcasting from the listener's perspective. To measure the effectiveness, the research conducted a survey based on Radio Nepal's initiative to evaluate its inclusive broadcasting. The findings reveal that Radio Nepal's inclusive broadcasting has been highly effective. Listeners from diverse linguistic communities have shown a growing interest in news and programs broadcast in their native languages. Moreover, broadcasting has successfully transcended linguistic boundaries, reaching beyond specific communities, thereby contributing to the conservation and respect of different languages by the state and society.

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Baker, Joanne C., et Richard W. Hunstead. « Composite Optical Spectra of Radio Quasars ». Symposium - International Astronomical Union 175 (1996) : 405–6. http://dx.doi.org/10.1017/s0074180900081250.

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Primarily to illustrate the effects of orientation on the optical properties of radio-loud quasars, we have created a set of composite optical spectra (see also Baker & Hunstead 1995). Optical spectra drawn from the 408-MHz Molonglo Quasar Sample (MQS) have been coadded in four sets according to R, the ratio of radio core-to-lobe flux, which is used as an orientation indicator (eg. Orr & Browne 1982). Compact steep-spectrum (CSS) quasars (see review by Fanti, this volume) have been combined separately, revealing for the first time many distinguishing features in their average spectra.

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Boccardi, B., G. Migliori, P. Grandi, E. Torresi, F. Mertens, V. Karamanavis, R. Angioni et C. Vignali. « The TeV-emitting radio galaxy 3C 264 ». Astronomy & ; Astrophysics 627 (juillet 2019) : A89. http://dx.doi.org/10.1051/0004-6361/201935183.

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Context.In March 2018, the detection by VERITAS of very-high-energy emission (VHE > 100 GeV) from 3C 264 was reported. This is the sixth, and second most distant, radio galaxy ever detected in the TeV regime.Aims.In this article we present a radio and X-ray analysis of the jet in 3C 264. We determine the main physical parameters of the parsec-scale flow and explore the implications of the inferred kinematic structure for radiative models of thisγ-ray emitting jet.Methods.The radio data set is comprised of VLBI observations at 15 GHz from the MOJAVE program, and covers a time period of about two years. Through a segmented wavelet decomposition method (WISE code), we estimated the apparent displacement of individual plasma features; we then performed a pixel-based analysis of the stacked image to determine the jet shape. The X-ray data set includes all available observations from theChandra, XMM, andSwiftsatellites, and is used, together with archival data in the other bands, to build the spectral energy distribution (SED).Results.Proper motion is mostly detected along the edges of the flow, which appears strongly limb brightened. The apparent speeds increase as a function of distance from the core up to a maximum of ∼11.5 c. This constrains the jet viewing angle to assume relatively small values (θ ≲ 10°). In the acceleration region, extending up to a de-projected distance of ∼4.8 × 104Schwarzschild radii (∼11 pc), the jet is collimating (r ∝ z0.40 ± 0.04), as predicted for a magnetically-driven plasma flow. By assuming that the core region is indeed magnetically dominated (UB/Ue > 1), the SED and the jet power can be well reproduced in the framework of leptonic models, provided that the high-energy component is associated to a second emitting region. The possibility that this region is located at the end of the acceleration zone, either in the jet layer or in the spine, is explored in the modeling.

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Deul, E. R., et W. B. Burton. « Radio Mapping ». Symposium - International Astronomical Union 133 (1988) : 311–21. http://dx.doi.org/10.1017/s0074180900139762.

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The mapping discussed in this paper is based on observations obtained from the 21–cm emission line of neutral atomic hydrogen. We will give an overview of the existing large surveys and present a homogeneous datacube that contains the most important surveys. This datacube was created by regridding the original observations, for the surveys included, onto a common denominator grid. Presenting a three dimensional dataset of intensities in one single image is impossible, therefore we made a film that displays in a time sequence a set of cuts (position–velocity maps) through the datacube. The advantage of showing the third coordinate in time is that the eye can now catch continuities in this coordinate that were previously hidden in the data.

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Karst, Nathaniel, Joshua Langowitz, Jessica Oehrlein et Denise Sakai Troxell. « Radio k-chromatic number of cycles for large k ». Discrete Mathematics, Algorithms and Applications 09, n^o 03 (7 mars 2017) : 1750031. http://dx.doi.org/10.1142/s1793830917500318.

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For a positive integer [Formula: see text], a radio k-labeling of a graph [Formula: see text] is a function [Formula: see text] from its vertex set to the non-negative integers such that for all pairs of distinct vertices [Formula: see text] and [Formula: see text], we have [Formula: see text] where [Formula: see text] is the distance between the vertices [Formula: see text] and [Formula: see text] in [Formula: see text]. The minimum span over all radio [Formula: see text]-labelings of [Formula: see text] is called the radio k-chromatic number and denoted by [Formula: see text]. The most extensively studied cases are the classic vertex colorings ([Formula: see text]), [Formula: see text](2,1)-labelings ([Formula: see text]), radio labelings ([Formula: see text], the diameter of [Formula: see text]), and radio antipodal labelings ([Formula: see text]. Determining exact values or tight bounds for [Formula: see text] is often non-trivial even within simple families of graphs. We provide general lower bounds for [Formula: see text] for all cycles [Formula: see text] when [Formula: see text] and show that these bounds are exact values when [Formula: see text].

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S. K. Vaidya et D. D. Bantva. « Radio Number for Strong Product } $ P_2 \otimes P_n$ ». Malaya Journal of Matematik 1, n^o 02 (1 avril 2013) : 29–36. http://dx.doi.org/10.26637/mjm102/004.

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A radio labeling of a graph $G$ is a function $f$ from the vertex set $V(G)$ to the set of non-negative integers such that $|f(u)-f(v)| \geq \operatorname{diam}(G)+1-d_G(u, v)$, where $\operatorname{diam}(G)$ and $d_G(u, v)$ are diameter and distance between $u$ and $v$ in graph $G$ respectively. The radio number $\operatorname{rn}(G)$ of $G$ is the smallest number $k$ such that $G$ has radio labeling with $\max \{f(v): v \in V(G)\}=k$. We investigate radio number for strong product of $P_2$ and $P_n$.

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ELrokh, Ashraf, Mohammed M. Ali Al-Shamiri et Atef Abd El-hay. « A Novel Radio Geometric Mean Algorithm for a Graph ». Symmetry 15, n^o 3 (21 février 2023) : 570. http://dx.doi.org/10.3390/sym15030570.

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Radio antennas switch signals in the form of radio waves using different frequency bands of the electromagnetic spectrum. To avoid interruption, each radio station is assigned a unique number. The channel assignment problem refers to this application. A radio geometric mean labeling of a connected graph G is an injective function h from the vertex set, V(G) to the set of natural numbers N such that for any two distinct vertices x and y of G, h(x)·h(y)≥diam+1−d(x,y). The radio geometric mean number of h, rgmn(h), is the maximum number assigned to any vertex of G. The radio geometric mean number of G, rgmn(G) is the minimum value of rgmn(h), taken over all radio geometric mean labeling h of G. In this paper, we present two theorems for calculating the exact radio geometric mean number of paths and cycles. We also present a novel algorithm for determining the upper bound for the radio geometric mean number of a given graph. We verify that the upper bounds obtained from this algorithm coincide with the exact value of the radio geometric mean number for paths, cycles, stars, and bi-stars.

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Leahy, Denis A., Felicity Merrick et Miroslav Filipović. « Radio Emission from Supernova Remnants : Model Comparison with Observations ». Universe 8, n^o 12 (8 décembre 2022) : 653. http://dx.doi.org/10.3390/universe8120653.

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Supernova remnants (SNRs) are an integral part in studying the properties of the Galaxy and its interstellar medium. For the current work, we compare the observed radio luminosities of SNRs to predictions based on a recent analytic model applied to 54 SNRs with X-ray observations. We use the X-ray data to determine the properties of shock velocities, ages and circumstellar densities for the SNRs, whereas shock radii are determined from catalogs. With this set of SNR properties, we can calculate the model radio emission and compare it to the observed radio emission for a sample of SNRs. This is the first time that this test has been carried out—previously the SNR properties were assumed instead of derived from X-ray data. With the assumption that the radio emission process depends on SNR properties in the form of power-law functions, we explore ways to improve the radio emission model. The main results of this study are (i) the model has significant deficiencies and cannot reproduce observed radio emission; and (ii) the model can be improved significantly by changing its dependence on SNR parameters, although the improved model is still not accurate. Significant work remains to improve the components of radio emission models, including changes to the SNR evolution model, the radio emitting volume, and the efficiencies for conversion of shock energy into relativistic electrons and for magnetic field amplification.

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Ilcev, Stojce Dimov. « The development of maritime radio communications ». International Journal of Maritime History 30, n^o 3 (août 2018) : 536–43. http://dx.doi.org/10.1177/0843871418784240.

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This paper provides an historical review of maritime mobile radio communications systems as a primary means of ensuring the safety and security of ships at sea. Safety at sea has always been a priority for seamen and shippers. Distress alerts at sea caused by the blind forces of Mother Nature or, more commonly, by human factors have occurred over many centuries, as seafarers often set sail with inadequate information about their course, navigation and weather conditions. Until the late nineteenth century, only audio and visual transfers of information from point to point were used. From then on, however, new methods, such as news and information via wire and then by radio communications systems, were introduced. So long as safety standards are met, it is also important to test innovations and technology transfer to develop devices that are more reliable than mobile radio communications.

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Eryigit, Salim, Suzan Bayhan, Jussi Kangasharju et Tuna Tugcu. « Optimal Cooperator Set Selection in Social Cognitive Radio Networks ». IEEE Transactions on Vehicular Technology 65, n^o 8 (août 2016) : 6432–43. http://dx.doi.org/10.1109/tvt.2015.2480781.

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Ibrahim, Intan Soliha, Assis Kamu, Jurry Foo et Juliana Abdul Wahab. « Women and Radio in Semporna, Sabah – In the Name of Development Communication ». IKAT : The Indonesian Journal of Southeast Asian Studies 6, n^o 1 (29 septembre 2022) : 29. http://dx.doi.org/10.22146/ikat.v6i1.71497.

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In the context of radio, the gist of development communication is how the radio is used to aid social development. Although there are studies on radio listenership, research on women's listening habits in Malaysia is inadequate, although women are dominant radio listeners globally. This study examines factors that motivate women's listening to the radio, mainly in Semporna, Sabah. The central question is how radio has become significant among women in Semporna? This research employs a quantitative research approach. A structured questionnaire was used to obtain information from 294 female respondents. A chi-square test, factor analysis, and Kruskal-Wallis test with Bonferroni correction were used to analyse the data. The findings of the chi-square test analysis revealed a significant link between radio listening and possessing a radio set at home (X2 = 33.871, df = 1, p 0.05). The Kruskal-Wallis test with Bonferroni correction was conducted to see whether the agreement score in listening to the radio for entertainment and peace of mind is different according to four factors: age, marital status, level of education and occupation. Thus, radio is no longer the primary medium to get information, except for undocumented people.

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Kristiyana, Samuel, Diky Siswanto et Prastyono Eko Pambudi. « Sistem Komunikasi Radio Terpadu Masyarakat Mitra Polhut dan Masyarakat Peduli Api di Kawasan Gunung Merapi ». Jurnal Pemberdayaan Umat 1, n^o 1 (25 février 2022) : 39–50. http://dx.doi.org/10.35912/jpu.v1i1.766.

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Abstract Purpose: to find out the Integrated Radio Communication System potential volunteers from the community who are members of the MPP and MPA to increase their understanding of mastery of radio communication tools, ethics, and coded communication and to follow the frequency regulations set by the Ministry of Communications and Information Technology. Methode: The community service method uses an Integrated Radio Communication System workshop and training for people who are members of the MPP and MPA on how to set up radio communication tools, using two-meter band radio communication procedures, communication ethics, and mastery of communication languages. Result: Design and installation of radio repeater Integrated Radio Communication System Workshop resulted in an understanding of the SKRT system and improved MPP and MPA capabilities. Mastery of communication tools, ethics, communication code language, and following frequency regulations set by the government. Limitations: By planning and implementing the SKRT and preparing volunteers from the community, MPP and MPA will support the main tasks and functions of the Taman Nasional Gunung Merapi for the protection and security and handling of the Mount Merapi eruption disaster. Research Contribution: Carrying out the implementation, in this case, is the Taman Nasional Gunung Merapi to plan and implement the SKRT and prepare the potential of the community to take joint responsibility for the conservation, protection, and security, and disaster response of Mount Merapi.

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Liang, Jia-Ming, Ching-Kuo Hsu, Jen-Jee Chen, Po-Han Lin, Po-Min Hsu et Tzung-Shi Chen. « Dynamic Set Planning for Coordinated Multi-Point in B4G/5G Networks ». Sensors 21, n^o 5 (3 mars 2021) : 1752. http://dx.doi.org/10.3390/s21051752.

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Coordinated Multi-Point (CoMP) is an important technique in B4G/5G networks. With CoMP, multiple base stations can be clustered to compose a cooperating set to improve system throughput, especially for the users in cell edges. Existed studies have discussed how to mitigate overloading scenarios and enhance system throughput with CoMP statically. However, static cooperation fixes the set size and neglects the fast-changing of B4G/5G networks. Thus, this paper provides a full study of off-peak hours and overloading scenarios. During off-peak hours, we propose to reduce BSs’ transmission power and use the free radio resource to save energy while guaranteeing users’ QoS. In addition, if large-scale activities happen with crowds gathering or in peak hours, we dynamically compose the cooperating set based on instant traffic requests to adjust base stations’ BSs’ transmission power; thus, the system will efficiently offload the traffic to the member cells which have available radio resources in the cooperating set. Experimental results show that the proposed schemes enhance system throughput, radio resource utilization, and energy efficiency, compared to other existing schemes.

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Dussel, Konrad. « Die Radio- und Fernsehgeräteproduktion in der BRD und der Außenhandel ». Vierteljahrschrift für Sozial- und Wirtschaftsgeschichte 96, n^o 2 (2009) : 195–211. http://dx.doi.org/10.25162/vswg-2009-0009.

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Zirkle, Thomas A., Matthew J. Filmer, Jonathan Chisum, Alexei O. Orlov, Eva Dupont-Ferrier, Joffrey Rivard, Matthew Huebner, Marc Sanquer, Xavier Jehl et Gregory L. Snider. « Radio Frequency Reflectometry of Single-Electron Box Arrays for Nanoscale Voltage Sensing Applications ». Applied Sciences 10, n^o 24 (9 décembre 2020) : 8797. http://dx.doi.org/10.3390/app10248797.

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Single-electron tunneling transistors (SETs) and boxes (SEBs) exploit the phenomenon of Coulomb blockade to achieve unprecedented charge sensitivities. Single-electron boxes, however, despite their simplicity compared to SETs, have rarely been used for practical applications. The main reason for that is that unlike a SET where the gate voltage controls conductance between the source and the drain, an SEB is a two terminal device that requires either an integrated SET amplifier or high-frequency probing of its complex admittance by means of radio frequency reflectometry (RFR). The signal to noise ratio (SNR) for a SEB is small, due to its much lower admittance compared to a SET and thus matching networks are required for efficient coupling ofSEBs to an RFR setup. To boost the signal strength by a factor of N (due to a random offset charge) SEBs can be connected in parallel to form arrays sharing common gates and sources. The smaller the size of the SEB, the larger the charging energy of a SEB enabling higher operation temperature, and using devices with a small footprint (<0.01 µm2), a large number of devices (>1000) can be assembled into an array occupying just a few square microns. We show that it is possible to design SEB arrays that may compete with an SET in terms of sensitivity. In this, we tested SETs using RF reflectometry in a configuration with no DC through path (“DC-decoupled SET” or DCD SET) along with SEBs connected to the same matching network. The experiment shows that the lack of a path for a DC current makes SEBs and DCD SETs highly electrostatic discharge (ESD) tolerant, a very desirable feature for applications. We perform a detailed analysis of experimental data on SEB arrays of various sizes and compare it with simulations to devise several ways for practical applications of SEB arrays and DCD SETs.

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Petrosian, Vahe, Jack Singal et Lukasz Stawarz. « Luminosity Correlations, Luminosity Evolutions, and Radio Loudness of AGNs from Multiwavelength Observations ». Proceedings of the International Astronomical Union 9, S304 (octobre 2013) : 172. http://dx.doi.org/10.1017/s174392131400369x.

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AbstractThe dichotomy of jet dominated versus accretion disk dominated AGNs or “radio-loud” vs “radio-quiet” quasars can be investigated by a simultaneous determination of the relative shape and evolution of the radio and optical luminosity functions, and the distribution of the radio loudness R defined as the ratio of radio to optical luminosities. This can be done from a multivariate data set containing observed fluxes, redshift, spectra, etc. We emphasize that when dealing with a multivariate data set it is imperative to first determine the true correlations, not those introduced by the observational selection effects, among the variables (e.g. Luminosity-luminosity, redshift-luminosity) before obtaining the individual distributions of the variables (e.g. Luminosity functions and density evolution). We use data from several sources including the SDSS (Data Release 7) and FIRST radio catalogs, with well defined optical and radio flux limits, and employ the non-parametric methods developed by Efron and Petrosian, designed to obtain unbiased correlations, distributions and evolution with redshift from data truncated due to observational biases. We determine the density and the luminosity evolutions in both wavebands, which shows significantly higher radio than optical luminosity evolution. From these we obtain true distribution of the radio loudness parameter which shows no sign of bi-modality and indicates that quasars were more radio loud at earlier epochs.

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Kowsalya, P., et D. Vijayalakshmi. « On Radio k – Chromatic Number for Mycielski of Some Graphs ». Indian Journal Of Science And Technology 17, n^o 39 (21 octobre 2024) : 4129–37. http://dx.doi.org/10.17485/ijst/v17i39.2315.

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Objectives: In radio networks, the main difficulty is managing the radio spectrum, assigning radio frequencies to transmitters optimally without any interferences. This study aims to find the smallest span of Mycielski of some graphs, the maximum color assigned to any node is called span. Methods : This study focused on the problem of reducing interference by modeling it with a radio k - coloring problem on graphs. Where transmitters are modeled as nodes in a graph, with edges connecting nodes that represent transmitters in close proximity to one another. For a graph , with node set , edge set and an integer , a radio k - coloring of is a function satisfying the condition for any two nodes and , where is the distance between and in . The radio k - coloring of , is the maximum color assigned to any node of and it is denoted by . The radio k -chromatic number of is the minimum value of taken over all radio k - coloring of and it is denoted by . Findings: This study obtained the radio k-chromatic number for Mycielski of some graphs for and 3 Novelty: To solve the channel assignment problem in radio transmitters, the interference graph is developed, and the channel assignment has been converted into a graph coloring. Reducing the interference by a radio k - coloring problem will motivate many researchers to find the radio k - coloring in various graphs. Keywords: Radio k – Coloring, Mycielski graph, Double Star graph, Triple Star graph, Sunlet graph, Helm graph and Closed Helm graph

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van Driel, W. « Radio quiet, please ! – protecting radio astronomy from interference ». Proceedings of the International Astronomical Union 5, S260 (janvier 2009) : 457–64. http://dx.doi.org/10.1017/s1743921311002675.

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AbstractThe radio spectrum is a finite and increasingly precious resource for astronomical research, as well as for other spectrum users. Keeping the frequency bands used for radio astronomy as free as possible of unwanted Radio Frequency Interference (RFI) is crucial. The aim of spectrum management, one of the tools used towards achieving this goal, includes setting regulatory limits on RFI levels emitted by other spectrum users into the radio astronomy frequency bands. This involves discussions with regulatory bodies and other spectrum users at several levels – national, regional and worldwide. The global framework for spectrum management is set by the Radio Regulations of the International Telecommunication Union, which has defined that interference is detrimental to radio astronomy if it increases the uncertainty of a measurement by 10%. The Radio Regulations are revised every three to four years, a process in which four organisations representing the interests of the radio astronomical community in matters of spectrum management (IUCAF, CORF, CRAF and RAFCAP) participate actively. The current interests and activities of these four organisations range from preserving what has been achieved through regulatory measures, to looking far into the future of high frequency use and giant radio telescope use.

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Wydaswari, Paramitha, Susanne Dida, FX Ari Agung Prastowo et Heru Ryanto. « Digital Marketing as a Repositioning Strategy for Radio Broadcasting Agent in Bandung - A Descriptive Study of OZ Radio’s Repositioning Through Instagram ». KnE Social Sciences 2, n^o 4 (13 juin 2017) : 101. http://dx.doi.org/10.18502/kss.v2i4.874.

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OZ Radio Bandung chooses Instagram as a one of their platform for its marketing that helps them promote their repositioning strategy, whichthey initiated on September 2015. OZ Radio Bandung promotes itself as a radio for young people only. By the end of 2015, OZ Radio Bandung set up a plan to reposition its audience segmentation from young people to young-adult. This paper describes OZ Radio Bandung’s usage of Instagram as a platform to reposition itself to its young-adult audience.

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Tan, Xuesong Jonathan, Jieran Wang et Yongjun Yuan. « Difference-Set-Based Channel Hopping for Minimum-Delay Blind Rendezvous in Multi-Radio Cognitive Radio Networks ». IEEE Transactions on Vehicular Technology 68, n^o 5 (mai 2019) : 4918–32. http://dx.doi.org/10.1109/tvt.2019.2906455.

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Galvin, T. J., M. T. Huynh, R. P. Norris, X. R. Wang, E. Hopkins, K. Polsterer, N. O. Ralph, A. N. O’Brien et G. H. Heald. « Cataloguing the radio-sky with unsupervised machine learning : a new approach for the SKA era ». Monthly Notices of the Royal Astronomical Society 497, n^o 3 (2 juillet 2020) : 2730–58. http://dx.doi.org/10.1093/mnras/staa1890.

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ABSTRACT We develop a new analysis approach towards identifying related radio components and their corresponding infrared host galaxy based on unsupervised machine learning methods. By exploiting Parallelized rotation and flipping INvariant Kohonen maps (pink), a self-organizing map (SOM) algorithm, we are able to associate radio and infrared sources without the a priori requirement of training labels. We present an example of this method using 894 415 images from the Faint Images of the Radio-Sky at Twenty centimeters (FIRST) and Wide-field Infrared Survey Explorer (WISE) surveys centred towards positions described by the FIRST catalogue. We produce a set of catalogues that complement FIRST and describe 802 646 objects, including their radio components and their corresponding AllWISE infrared host galaxy. Using these data products, we (i) demonstrate the ability to identify objects with rare and unique radio morphologies (e.g. ‘X’-shaped galaxies, hybrid FR I/FR II morphologies), (ii) can identify the potentially resolved radio components that are associated with a single infrared host, (iii) introduce a ‘curliness’ statistic to search for bent and disturbed radio morphologies, and (iv) extract a set of 17 giant radio galaxies between 700 and 1100 kpc. As we require no training labels, our method can be applied to any radio-continuum survey, provided a sufficiently representative SOM can be trained.

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Puliaev, S., et A. H. Andrei. « Investigations on Optical and Radio Reference Frames ». International Astronomical Union Colloquium 165 (1997) : 449–52. http://dx.doi.org/10.1017/s0252921100046947.

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AbstractFeatures of the systematic errors of the Carlsberg Automatic Meridian Circle (CAMC) reference frame are investigated using a secondary radio reference frame defined by a set of astrometric VLA, VLBI and submillimetric positions of radio stars, taken from the literature. The radio positions of 62 stars are compared against the corresponding CAMC positions. The systematic errors of the CAMC catalogue are found to be generally smaller than 005. The radio positions were also compared with the positions obtained with the Bordeaux Automatic Meridian Circle (BORD). It was found a good coincidence between (CAMC–Radio) and (BORD–Radio) systematic differences.

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Zhang, Lixia, Junhui Fan et Jingtian Zhu. « Radio loudness and classification for radio sources ». Publications of the Astronomical Society of Japan 73, n^o 2 (30 janvier 2021) : 313–25. http://dx.doi.org/10.1093/pasj/psaa122.

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Abstract The extragalactic radio sources are divided into two subclasses (radio-loud and radio-quiet sources) in the literature using radio loudness (R), which is defined as the ratio of radio emission to optical emission, but the boundary R-value separating the two classes is different in various sources. In this work, a sample of 2419 objects from the 13th catalog of quasars and active nuclei is used to build a boundary for the two subclasses. To do so, we compiled the radio and optical data, calculated their radio and optical indexes, made K-correction, obtained the radio loudness, and adopted a Bayesian analysis method to the logarithm of radio loudness for classification. We also investigated the correlations of radio loudness with radio/optical luminosities. Our main conclusions are summarized as follows: (1) The distribution of the logarithm of radio loudness (log R) is bimodal, the sources with log R < 1.26 are classified as radio-quiet sources, and those with log R > 1.26 are classified as radio-loud ones from the Bayesian analysis method. (2) The average radio-optical effective spectral index of radio-quiet sources is 〈αRO〉 = 0.05, while that of radio-loud sources is 〈αRO〉 = 0.55. (3) There are positive correlations between radio luminosity and radio loudness for both radio-loud sources and radio-quiet sources. (4) A dividing line of separating the distribution of the clusters on the diagram of radio loudness against radio luminosity was obtained statistically to set the boundary between radio-loud sources and radio-quiet sources, with an accuracy of $99.73\%$ based on the classification result from the Bayesian analysis method.

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Krutnik, Frank. « Chiller-Dillers for the Shiver-and-Shudder Set : The Whistler Film Series ». Film Studies 17, n^o 1 (2017) : 49–72. http://dx.doi.org/10.7227/fs.17.0004.

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This article explores the serial dynamics behind and within the succession of B-films Columbia Pictures developed from the popular CBS radio programme The Whistler. It examines how this anthology series developed within Columbias on going strategy of low-budget production, while responding to specfiic industrial challenges facing 1940s B-films. Besides looking at broader synergies between radio and cinema during this period, the article also qualies the tendency to categorise the Whistler movies as films noir, suggesting it is more productive to view them as products of a broader pulp serialscape that is shaped by alternative cultural and industrial logics.

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V. T., Brindha Mary, C. David Raj et C. Jayasekaran. « EVEN RADIO MEAN GRACEFUL LABELING ON DEGREE SPLITTING OF SNAKE RELATED GRAPHS ». South East Asian J. of Mathematics and Mathematical Sciences 18, n^o 02 (24 septembre 2022) : 197–204. http://dx.doi.org/10.56827/seajmms.2022.1802.18.

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A radio mean labeling of a connected graph G is an injection φ from the vertex set V(G) to N such that the condition d(u, v) + & φ(u)+φ(v) 2 ' ≥ 1 + diam(G) holds for any two distinct vertices u and v of G. A graph which admits radio mean labeling is called radio mean graph. The radio mean number of φ, rmn(φ), is the maximum number assigned to any vertex of G. The radio mean number of G, rmn(G), is the minimum value of rmn(φ) taken over all radio mean labeling φ of G. In this paper we introduce a new concept even radio mean graceful labeling and we investigate th

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Bane, Kshitij S., Indrajit V. Barve, G. V. S. Gireesh, C. Kathiravan et R. Ramesh. « A 1–bit Raw Voltage-recording System for Dedicated Observations of Transients at Low Radio Frequencies ». Astrophysical Journal Supplement Series 272, n^o 2 (16 mai 2024) : 27. http://dx.doi.org/10.3847/1538-4365/ad4296.

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Abstract Recently we had reported commissioning of a prototype for pulsar observations at low radio frequencies (<100 MHz) using log-periodic dipole antennas in the Gauribidanur Radio Observatory (≈77°E, 14°N) near Bangalore in India (https://www.iiap.res.in/?q=centers/radio). The aforementioned system (the Gauribidanur Pulsar System) is currently being augmented to directly digitize the radio-frequency signals from the individual antennas in the array. Our initial results using a 1–bit raw voltage-recording system indicate that such a back-end receiver offers distinct advantages like (i) simultaneous observations of any set of desired directions in the sky with multiple offline beams and smaller data rate/volume, and (ii) archival of the observed data with minimal resources for reanalysis in the future, either in the same or a different set of directions in the sky.

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KARPAGARAJESH, G., S. NARMATHA, A. V. NIRANJANA, M. RAMYA et P. SIVAGAMI. « ENERGY EFFICIENCY AND ENHANCEMENT IN COGNITIVE RADIO CELLULAR SET-UP ». i-manager’s Journal on Electronics Engineering 9, n^o 2 (2019) : 36. http://dx.doi.org/10.26634/jele.9.2.15397.

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Perks, Simon. « Russian radio telescope set to lift veil on deep space ». Physics World 24, n^o 05 (mai 2011) : 10. http://dx.doi.org/10.1088/2058-7058/24/05/21.

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Newman, Gregory A., Stephan Recher, Bülent Tezkan et Fritz M. Neubauer. « 3D inversion of a scalar radio magnetotelluric field data set ». GEOPHYSICS 68, n^o 3 (mai 2003) : 791–802. http://dx.doi.org/10.1190/1.1581032.

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A radio magnetotelluric (MT) field data set, acquired in scalar mode, over a buried waste site has been successfully analyzed using a 3D MT inversion scheme using nonlinear conjugate gradients. The results of this analysis demonstrate the utility of the scheme where more than 4800 data points collected on multiple measurement profiles have been inverted simultaneously. The resulting image clearly detects the buried waste; when receiver profiles cross pit boundaries, the image maps the lateral extent of the pit. However, the base of the pit is poorly resolved, and depends upon the starting model used to launch the inversion. Hence, critical information on whether contamination is leaching into a resistive gravel bed lining the base of the pit, as well as the deeper geological horizons consisting of brown coal, clay, and tertiary sands, is inconclusive. Nevertheless, by incorporating within the inversion process a priori information of the background media that is host to the waste, sharper images of the base of the pit are obtained, which are in good agreement with borehole data. The 3D analysis applied in this paper overcomes previous limitations in the radio magnetotelluric (RMT) method using 2D data analysis and inversion. With 3D analysis, it is unnecessary to make assumptions regarding geological strike, and near‐surface statics can be accommodated in both source polarizations. Our findings also indicate that 2D MT interpretation can overestimate the pit's depth extent. This may lead to the erroneous conclusion that the geological horizons beneath the pit have been contaminated.

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Souihli, Oussama, et Tomoaki Ohtsuki. « Typical Set Cognitive Sensing ». ISRN Communications and Networking 2011 (29 août 2011) : 1–10. http://dx.doi.org/10.5402/2011/709091.

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In cognitive radio (CR) cooperative sensing schemes, wireless sensor nodes deployed in the network sense the licensed spectrum and send their local sensing decisions to a fusion center (FC) that makes a global decision on whether to allow the unlicensed user transmit on the licensed spectrum, based on a decision (fusion) rule. k-out-of-N is widely used in the literature owing to its practical simplicity. Regrettably, it exhibits a tradeoff between the achievable probabilities of false alarm and miss detection, which could have consequent effects on the performance of CR. In this paper, based on the notion of typical sequences, we propose a novel fusion rule in which the false alarm and miss detection probabilities can be simultaneously made as small as desired (asymptotically zero as the number of sensors goes to infinity).

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Marongiu, M., C. Guidorzi, G. Stratta, A. Gomboc, N. Jordana-Mitjans, S. Dichiara, S. Kobayashi, D. Kopač et C. G. Mundell. « Radio data challenge the broadband modelling of GRB 160131A afterglow ». Astronomy & ; Astrophysics 658 (27 janvier 2022) : A11. http://dx.doi.org/10.1051/0004-6361/202140403.

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Context. Gamma-ray burst (GRB) afterglows originate from the interaction between the relativistic ejecta and the surrounding medium. Consequently, their properties depend on several aspects: radiation mechanisms, relativistic shock micro-physics, circumburst environment, and the structure and geometry of the relativistic jet. While the standard afterglow model accounts for the overall spectral and temporal evolution for a number of GRBs, its validity limits emerge when the data set is particularly rich and constraining, especially in the radio band. Aims. We aimed to model the afterglow of the long GRB 160131A (redshift z = 0.972), for which we collected a rich, broadband, and accurate data set, spanning from 6 × 108 Hz to 7 × 1017 Hz in frequency, and from 330 s to 160 days post-burst in time. Methods. We modelled the spectral and temporal evolution of this GRB afterglow through two approaches: (1) the adoption of empirical functions to model an optical/X-ray data set, later assessing their compatibility with the radio domain; and (2) the inclusion of the entire multi-frequency data set simultaneously through the Python package named SAGA (Software for AfterGlow Analysis), to obtain an exhaustive and self-consistent description of the micro-physics, geometry, and dynamics of the afterglow. Results. From deep broadband analysis (from radio to X-ray frequencies) of the afterglow light curves, GRB 160131A outflow shows evidence of jetted emission. Moreover, we observe dust extinction in the optical spectra, and energy injection in the optical/X-ray data. Finally, radio spectra are characterised by several peaks that could be due to either interstellar scintillation (ISS) effects or a multi-component structure. Conclusions. The inclusion of radio data in the broadband set of GRB 160131A makes a self-consistent modelling barely attainable within the standard model of GRB afterglows.

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Egoshkina, V. A. « The format of radio stations and signs of the format radio program ». Communication studies, n^o 2 (2017) : 61–68. http://dx.doi.org/10.24147/2413-6182.2017.2.61-68.

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Radio station must have original content, which will be demanded by the audience, and distinctive features, which can set this radio station from a number of similar, in order to operate successfully. In this regard in the works of a number of researchers becomes relevant the concept of “format”, which allows to reveal the specificity of certain media product. The concept “format” is not fully understood and fully described. In the article it considers approaches to the definition of the term «format», which is relevant for broadcast, presents the classifications of formats of radio stations, highlights signs of format, which allow analyzing radio program.

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Zakharenko, V. V., V. B. Ryabov, I. P. Kravtsov, K. Yu Mylostna, V. Yu Kharlanova, I. Y. Vasylieva, O. M. Ulyanov et al. « SPORADIC RADIO EMISSION OF SPACE OBJECTS AT LOW-FREQUENCIES ». Radio physics and radio astronomy 26, n^o 2 (23 juin 2021) : 99–129. http://dx.doi.org/10.15407/rpra26.02.099.

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Purpose: The results of studies of sporadic radio emission of several types of space radio sources, including neutron stars and planets of the Solar System, are presented. The aim of this work is to review the latest achievements in the study of low-frequency radio emission of the Solar System planets and transient signals similar to pulsar pulses using the UTR-2 radio telescope. The importance of the development of the verification methods of the spaceborne radio emission in the study of sporadic signals from various sources is shown. Design/methodology/approach: The studies of sporadic signals of different nature are based on the common set of procedures for cleaning records from the terrestrial radio frequency interference (RFI) in the frequency-time pattern using the information on the nature of the particular type of sporadic radio emission, possible types of interference and signal distortion. Characteristic features of sporadic radio emission of different sources are given, and for each of them the optimal method of signal extraction is developed. The efficiency of the developed procedures for cleaning from noise using adjustable parameters is shown. This is done on the basis of observations of diverse types of space radio sources, such as lightnings in the atmospheres of planets, single pulses of neutron stars and sporadic radio emission of Jupiter. Findings: The developed methods of signal extraction detection in the presence of radio-interference have allowed obtaining the unique results such as: the distribution of the total intensity of single pulses of neutron stars depending on the galactic latitude; the automatic search of lightnings in the Saturn’s atmosphere in data due to the carefully elaborated RFI mitigation procedures, which made it possible to obtain the Saturn electrostatic discharge (SED) emission parameters based on the most complete set of events. Increased efficiency of the selection of Jupiter’s S-radiation signals despite the data corruption by the presence of radio-interference, which was reached due to the carefully chosen parameters of data cleaning procedures, have allowed us to detect short and intensive bursts, being the most informative for determining the physical parameters of radio emission in the area of their generation. Conclusions: The large effective area and high sensitivity of the UTR-2 radio telescope allow making the sporadic radio emission study with high temporal and frequency resolutions. Due to these factors we can apply a wide range of methods of space signals’ detection in the presence of terrestrial radio-frequency interference of natural and artificial origin. The data cleaning parameters allow accounting for the characteristic features of space signals and to obtain important and even unique scientific results. Key words: decameter wavelength range; UTR-2; sporadic radio emission; transients; lightning in the atmospheres of planets; Jupiter S-bursts

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Ma, Bao Ke, Li Xin Guo et Bei Chen Zhang. « Prediction the Chaotic Time Series of the Radio Signal Propagates through the Ionosphere ». Advanced Materials Research 403-408 (novembre 2011) : 1487–90. http://dx.doi.org/10.4028/www.scientific.net/amr.403-408.1487.

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The signal distortion will be taken place and a set of attenuation time series will also be produced due to the interaction between the radio wave and the ionospheric irregularities when radio wave propagates through the ionosphere. In this article, based on the traditional chaotic time series prediction and the characteristic of the attenuation time series of the ionosphere, the traditional chaotic prediction method is modified, and a more suitable method is given. Final, by using the modified method, a set of attenuate amplitude time series of the radio signals which propagates through the ionosphere were predicted, and analyzed its prediction accuracy. The results showed that the modified prediction method is very good and accuracy at the short-term.

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Corcoran, Kyle A., Scott M. Ransom et Ryan S. Lynch. « No MSP Counterparts Detected in GBT Searches of Spider Candidates 4FGL J0935.3+0901, 4FGL J1627.7+3219, and 4FGL J2212.4+0708 ». Research Notes of the AAS 7, n^o 3 (7 mars 2023) : 41. http://dx.doi.org/10.3847/2515-5172/acc17d.

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Abstract We performed radio searches for the “spider” millisecond pulsar (MSP) candidates 4FGL J0935.3+0901, 4FGL J1627.7+3219, and 4FGL J2212.4+0708 using the Green Bank Telescope in an attempt to detect the proposed radio counterpart of the multi-wavelength variability seen in each system. We observed using the VEGAS spectrometer, centered predominantly at 2165 MHz; however, we were also granted observations at 820 MHz for 4FGL J1627.7+3219. We performed acceleration searches on each data set using PRESTO as well as additional jerk searches of select observations. We see no evidence of a radio counterpart in any of the observations for each of the three systems at this time. Additional observations, perhaps at different orbital phases (e.g., inferior conjunction), may yield detections of an MSP in the future. Therefore, we urge continued monitoring of these systems to fully characterize the radio nature, however faint or variable, of each system.

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