... Generalized maximum entropy method and its application to antenna pattern reconstruction. In this paper the Generalized maximum entropy method and its application to the reconstruction of two-dimensional complex functions (namely, far-field antenna pattern distribution) from nonuniformly distributed samples are considered. ... It is shown that the Generalized maximum entropy method is sufficiently stable in the presence of errors. ...

This is a list of astronomical data available on the World Wide Web which I put together for a lecture at the NEON archive school, held at ESO in August 2006, organized by: . ... Mostly) Large Area Surveys and Catalogues , where "large" means covering at least ~ 10% of the sky, although a selection of some smaller-area surveys is also included; . ... The NRAO VLA Sky Survey (NVSS) [1.4 GHz] . ... SuperCOSMOS Sky Surveys USNO Catalogues . ... ESO Online Digitized Sky Survey Guide Star Catalogues . ...

... GAMMA-RAY BURSTS . Nature of the cosmic gamma-ray bursts (GRB) is still not clear, but there are arguments in favor of their cosmological origin with the red shifts up to 3-4. Cosmological GRB produce huge amount of energy, which is considered in the form of an expanding fireball, or rapidly (ultrarelativistically) moving cannon balls. ... To explain this phenomenon a specific distribution of matter around the source was considered. ... previous page . next page . ... CYGAM (PDF, 450 Kb) . ...

Chair of solid state physics . ... The Physics of Phonons . ... In the first part of the course “The Physics of Phonons” the dynamics of atoms in one- and three- dimensional crystalline lattices is considered in detail. The quasiparticle conception in solids, taking phonons as an example, is discussed; creation and annihilation operators of phonons, main properties of acoustic and optical phonons dispersion laws, density of phonon states. ... Crystalline state. ... Acoustic and optical phonons. ...

... The procedure of radiometer signal integration can be considered as a sort of reducing dimension of the initial sampling space, where the samples are the result of analog-to-digital conversion. ... The probability distribution of the signal and spikes is completely known. ... The quality of the considered algorithm could be also illustrated by Figure 2 . ... One could see the considered adaptive algorithm is preferable even by low degree of compression, because all spikes have been depressed. ...

. annotation of talk . Igor D. Novikov . Wormholes . We consider new models of the static wormholes and give interpretation of their properties. We also consider the physical effects of propagation of radiation through a wormholes throat.

Using the Huygens and Babinet principles van de Hulst [ 11 ] considered the problem of light scattering and extinction by a particle having the size and the refractive index . ... The absorption cross-section is . ... The range of applicability of the anomalous diffraction theory for the scattering amplitude is limited by small angles, however the formules for the cross-sections became good approximations for a wide class of particles. ... This problem for spherical particles was solved by A.Ya. ...

Teaching courses . for student of the Department of Astrophysics and Stellar Astronomy . ... Geophysics and physics of the planets (Kurt, Panteleev) . ... Close Binary Stars . ... Solar Physics . ... This is introductory course for students of the third year of education which are familiar with elementary astronomy and general physics. ... The one-year course includes theory of radiation transfer, theory of internal stellar structure with account of binary systems with compact comapnions. ...

... The dynamics of silicate and graphite particles with radii of (0.1-2) 10 -5 cm in the vicinity of the Milky Way is considered. The equation of motion of dust grains is integrated with gravitational attraction, radiation pressure, gas drag, and dust destruction taken into account. The effect of other factors on the motion of grains are discussed. ... Dust is swept out of the Galaxy by radiation pressure from stars at a rate of 0.04 M o yr -1 . ...

... user-defined data file formats . ... better integration with a user's analysis routines To add such functionality to SAOimage, we developed the XPA Messaging System that allows X programs to define points of public access through which data and commands can be exchanged with external programs. ... We have utilized XPA to develop "SAOimage: The Next Generation" (SAOtng), an extensible image display service that can cooperate with other processes and programs. ... SAOtng help pages . ...

... 2006 May 31 . Simulated Gamma-ray Sky . Credit: GLAST DC2 . Explanation: Scheduled for launch in 2007, the Gamma-ray Large Area Space Telescope (GLAST) will explore the Universe in gamma-rays , the most energetic form of light. To get ready, consider this dynamic gamma-ray sky animation - constructed from simulating the first 55 days (seen above at one frame per day) of GLAST observations of cosmic gamma-ray sources. ... So what shines in this gamma-ray sky ? ... About APOD | ...

... Credit Copyright: GLAST DC2 Explanation: Scheduled for launch in 2007, the Gamma-ray Large Area Space Telescope (GLAST) will explore the Universe in gamma-rays , the most energetic form of light. To get ready, consider this dynamic gamma-ray sky animation - constructed from simulating the first 55 days (seen above at one frame per day) of GLAST observations of cosmic gamma-ray sources. ... So what shines in this gamma-ray sky ? ... Publications with keywords: gamma ray - simulation - GLAST . ...

spaceweb@oulu.fi - last update: 28 May 1995, 0800 UT . Advanced plasma theories are extremely important when one tries to explain, for example, the various waves and instabilities found in the plasma environment. ... In the kinetic theory it is necessary to know only the distribution function for the system of particles. ... The dependence of the distribution function on the independent variables r , v , and t is governed by an equation known as the Boltzmann equation . ... Hot plasma theory . ...

... The plotter allows various annotations (lines, arrows, text and ``spans'') to be added to the plot. ... The values are in world coordinates. ... axhline(y, xmin, xmax) . ... avhline(x, ymin, ymax) . ... xmin, xmax) . Overlay a transparent colour rectangle. ymin and ymax are given in world coordinates while xmin and xmax are given in relative coordinates . ... Overlay a transparent colour rectangle. ymin and ymax are given in relative coordinates while xmin and xmax are given in world coordinates . ...

Next: Imaging by an Optimizing Method . ... A big advantage of this numerical integrator is its stability: the error in the semi-major axis and the eccentricity depends only on the step size and does not grow with an increasing number of time steps. ... As the integration time increases, the numerical results become more contaminated by various errors. ... A new symplectic integrator produces no secular truncation errors in the actions of a Hamiltonian system. ...

... Steven L. Smith . NASA International Space Station Program Liaison to the European Space Agency . ... SPECIAL HONORS: NASA Distinguished Service Medals (two), NASA Outstanding Leadership Medal, NASA Space Flight Medal, NASA Exceptional Service Medal, IBM Outstanding Technical Achievement Award and IBM Outstanding Community Service Award. ... NASA EXPERIENCE: Smith is a veteran of four space flights covering 16 million miles and seven space walks totaling 49 hours and 25 minutes. ... DECEMBER 2013 ...

... We will consider the rms, (K), for observations with a receiver of system temperature, T , frequency resolution, per polarization, and total integration time per observing cycle, . ... For ``in-band'' frequency switching, the line under investigation is always in the observing band. ... Position Switching or ``Out-of-Band'' Frequency Switching: Here the line is only observed for one half of the time, with noise being present all of the time. ...

... We now consider estimation of count rates for objects with stellar, power law, and emission line spectra. To estimate the number of electrons collected from a point source of apparent visual magnitude V, one can use the equation: . ... If one knows the spectral index a (which is zero for a source with a flat continuum), V + AB_nu can also be calculated as the monochromatic Oke system magnitude at the corrected mean wavelength of the filter: . ... 6.3.3 - Count Rates for Emission Line Sources . ...

... Appropriate values of DIT the integration time (DIT secs) for each individual integration, are lmited by various considerations. N.B. Ndit individual Integration s each of DIT secs are coadded to form a single Exposure of time Ndit*DIT]. The recommended minimum DIT is one sec (the minimum possible exposure time) or the value at which the noise becomes sky (rather than detector) limited. ... The recommended maximum DIT is such as to keep the detector wells less than half full. ... 40 sec . ...

CREW 21/22 . ... NII TsPK picture Timothy John CREAMER . ... NASA Astronaut . ... In summer 2000 Creamer was assigned to the Space Station Branch of the Astronaut Office where he was engaged in the development of the computer equipment for Space Station and Control Center, as well as the Local Area Network integrating different modules of the International Space Station. ... On February 12, 2008 NASA officially declared of his assignment to the backup crew for Expedition 19 to the ISS. ...