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A Brief Overview of the Developments of the Cognitive Radio Technology  [PDF]
Mayank Gupta , Nimrat Kumar Narula , VK Panchal , Ashok chandra
International Journal of Advanced Computer Research , 2012,
Abstract: Cognitive radio’s rising popularity among various engineers, scientists and researchers can be credited to the increasing number of users of wireless technology and the radio spectrum which is limited. In this paper, various advances which have been made so far to improvise cognitive radio technology have been discussed in brief to give the reader an overview of this emerging technology. The basics of cognitive radio networks are introduced first and then various developments on different aspects of this technology are discussed.
Recent Developments in the Remote Radio Control of Insect Flight  [PDF]
Hirotaka Sato,Michel M. Maharbiz
Frontiers in Neuroscience , 2010, DOI: 10.3389/fnins.2010.00199
Abstract: The continuing miniaturization of digital circuits and the development of low power radio systems coupled with continuing studies into the neurophysiology and dynamics of insect flight are enabling a new class of implantable interfaces capable of controlling insects in free flight for extended periods. We provide context for these developments, review the state-of-the-art and discuss future directions in this field.
Nell’anno di Nikola Tesla  [cached]
Persida Lazarevi? Di Giacomo
Studi Slavistici , 2006,
Abstract: The 150th Anniversary Celebration of Nikola Tesla The paper deals with the 150th anniversary celebration of Nikola Tesla, the greatest ever Yugoslav scientist. Due to his origins, Tesla is contended between Serbia and Croatia, but he is also considered to be an American scientist since he registered most of his patents in the USA. Although there is some dissension between Serbia and Croatia regarding the historical facts about Tesla’s life, it can be asserted that Tesla appears to be an example of collaboration among the former Yugoslav countries. Tesla, however, deserves to be remembered as well as the author of autobiographical prose (My Inventions; Some Personal Recollections; A Strange Experience by Nikola Tesla) and as the protagonist of many works published in Serbo-Croatian and in English, such as Milo Crnjanski’s drama Tesla (1969) or The Hunger and Ecstasy of Vampires (1996) by Brian M. Stableford, for example. This fact should not be neglected and actually should be researched more fully.
Lowering Inferred Cluster Magnetic Field Strengths - the radio galaxy contributions  [PDF]
L. Rudnick,K. Blundell
Physics , 2003, DOI: 10.1086/373891
Abstract: We present a detailed examination of the relationship between the magnetic field structures and the variations in Faraday Rotation across PKS1246-410, a radio source in the Centaurus cluster of galaxies, using data from Taylor, Fabian and Allen. We find a significant relationship between the intrinsic position angle of the polarization and the local amount of Faraday Rotation. The most plausible explanation is that most or all of the rotation is local to the source. We suggest that the rotations local to cluster radio galaxies may result from either thermal material mixed with the radio plasma, or from thin skins of warm, ionized gas in pressure balance with the observed galaxy or hot cluster atmospheres. We find that the contribution of any unrelated cluster Rotation Measure variations on scales of 2 - 10 arcsec are less than 25 rad/m^2; the standard, although model dependent, derivation of cluster fields would then lead to an upper limit of approximately 0.4 microGauss on these scales. Inspection of the distributions of Rotation Measure, polarisation angle and total intensity in 3C75, 3C465 and Cygnus A also shows source-related Faraday effects in some locations. Many effects can mask the signatures of locally-dominated RMs, so the detection of even isolated correlations can be important, although difficult to quantify statistically. In order to use radio sources such as shown here to derive {\it cluster-wide} magnetic fields, as is commonly done, one must first remove the local contributions; this is not possible at present.
NIKOLA TESLA AND THE X-RAY  [PDF]
Rade R. Babic
Acta Medica Medianae , 2005,
Abstract: After professor Wilhelm Konrad R ntgen published his study of an x-ray discovery (Academy Bulletin, Berlin, 08. 11. 1895.), Nikola Tesla published his first study of an x-ray on the 11th of March in 1896. (X-ray, Electrical Review). Until the 11th of August in 1897 he had published ten studies on this subject. All Tesla,s x-ray studies were experimental, which is specific to his work. Studying the nature of the x-ray, he established a new medical branch-radiology. He wrote:” There’s no doubt that in any part of the body, small metal objects, bone and lime shadows could be found with no mistake".
Nikola Tesla and robotics  [PDF]
Vukobratovi? Miomir
Serbian Journal of Electrical Engineering , 2006, DOI: 10.2298/sjee0603163v
Abstract: The paper analyzes some of Tesla's works and his most remarkable views concerning the problem of formulating theoretical bases of automatic control. As a tribute to Tesla's work on remote control of automated systems, as well to his (at the time) far-seeing visions, special attention is paid to solving complex problem of control and feedback application. A more detailed discussion of the way and origin of formulating theoretical bases of automatic control are given. Besides, in more detail are presented the related pioneering works of Professor Nicholas Bernstein, great Russian physiologist who formulated the basic rules of the self-regulating movements of the man. Bernstein has achievements of highest scientific significance that has been in a direct function of identifying and proving the priority of his pioneering contributions in the domain of feedback, i.e. control and principles of cybernetics.
Recent developments of inverse Compton scattering model of pulsar radio emission  [PDF]
G. J. Qiao,R. X. Xu,J. F. Liu,B. Zhang J. L. Han
Physics , 1999,
Abstract: Many theoretical efforts were made to understand the core and conal emission identified from observations by Rankin (1983) and Lyne and Manchester (1988). One of them, named as inverse Compton scattering (ICS) model (Qiao & Lin 1998), has been proposed. It is found in the model that: there are central or `core' emission beam, and one or two hollow conical emission beams; the different emission components are emitted at different heights; owing to different radiation components emitted from different height, the observed emission beams can be shifted from each other due to retardation and aberration effects; the sizes of emission components change with frequencies. Recent developments of the model include: simulations of pulse profiles at different frequencies; studying the basic polarization properties of inverse Compton scattering in strong magnetic fields; computing the polarizations and spectrum of core and cones. A new classification system was also proposed. The main results calculated from the model are consistent with the observations.
NIKOLA TESLA AND THE X-RAY HARMFULNESS
Rade R. Babi?
Acta Medica Medianae , 2005,
Abstract: Nikola Tesla was the first scientist to point out that the x-ray could damage a live cell. He carefully noted the visible effects of the x-ray on human body and explained its harmful activity on the live cell. Therefore, he tried to find some means of protection from the x-ray harmfulness. He suggested to set an aluminium board between the person irradiated and the x-ray tube for the sake of protection. He also indicated the importance of law application.
Nikola Tesla discovered ‘very special radiation’ or x-radiation
Balti? Vladimir,Balti? Milan
Archive of Oncology , 2007, DOI: 10.2298/aoo0704100b
Abstract: Nikola Tesla was an ingenious and briliant scintifist which contributed to the science and technology prosperity of the world. Nikola Tesla discovered high frequency oscillator 1891 year, and afterwards, single electrode X-ray tube without target electrode, electron (“particles charged with electricity”), Bremsstrahlung or “breaking radiation” or “very special radiation” (X-radiation) in 1892 year, biological hazards of X-rays, and more about 700 inventions, and 112 patents. Tesla's research work in the field of X-rays was stopped in 1895 because burned in his laboratory. When W. C. R ntgen 1895, recognition X-rays, Tesla restored his work on this field and sent R ntgen a telegram with congratilations and R ntgen shows obtained with X-ray tubes which operated with high frequency currents. Tesla discovered many secret of nature.
Contributions of GRBs and Cen A-like Radio Galaxies to the Cosmic Gamma-ray Background  [PDF]
K. Watanabe,D. H. Hartmann
Physics , 2001, DOI: 10.1063/1.1419445
Abstract: The contribution to the cosmic diffuse gamma-ray background (CGB) from Gamma Ray Bursts (GRBs) is studied in the 40 keV - 2 MeV regime. We use High Energy Resolution (HER) data from the Burst And Transient Source Experiment (BATSE) aboard the Compton Gamma-Ray Observatory (CGRO) to generate a GRB template spectrum. Although the GRB contribution to the CGB is generally small, in comparison to the dominant flux from Type Ia supernovae, the integrated GRB flux is in fact comparable to that from SNIa in the narrow 10-40 keV range. GRBs contribute to the CGB at the same level as Type II supernovae do. Although BATSE data are not available below ~40 keV, extrapolation of the template spectrum suggests that bursts can fill a significant part of the existing gap between Seyfert galaxies (dominating the CGB below ~ 100 keV) and SNIa (dominating at ~1 MeV). We estimate contributions from Cen A-like (FR I) radio galaxies in this energy regime, where INTEGRAL data is expected to provide major advances.
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