Оптимизация схемы полета к астероидам главного пояса с использованием орбиты искусственного спутника Марса
Formulation and general procedure for solving the problem and study the flight patterns of main-belt asteroids with use orbits in the vicinity of Mars were discussed.
Many environmental stimuli present a quasi-rhythmic structure at different timescales that the brain needs to decompose and integrate. Cortical oscillations have been proposed as instruments of sensory de-multiplexing, i.e., the parallel processing of different frequency streams in sensory signals. Yet their causal role in such a process has never been demonstrated. Here, we used a neural microcircuit model to address whether coupled theta–gamma oscillations, as observed in human auditory cortex, could underpin the multiscale sensory analysis of speech. We show that, in continuous speech, theta oscillations can flexibly track the syllabic rhythm and temporally organize the phoneme-level response of gamma neurons into a code that enables syllable identification. The tracking of slow speech fluctuations by theta oscillations, and its coupling to gamma-spiking activity both appeared as critical features for accurate speech encoding. These results demonstrate that cortical oscillations can be a key instrument of speech de-multiplexing, parsing, and encoding.
Several missions are planned in Russia to launch spacecraft into the vicinity of the Solar-Terrestrial collinear libration points. The first of them is Spectr-Roentgen-Gamma intended to explore the sky in X-ray and Gamma-ray band. There are technical constraints on this project’s realization, influencing the scenario of inserting the spacecraft into the operational orbit. One of these constraints is the location of the available ground station.
Due to the high latitude of Russian stations it is impossible to have visibility of the spacecraft from them during those phases of flight when the spacecraft is well below the ecliptic plane. To avoid this phenomenon, it is necessary to decrease the orbit amplitude in the direction orthogonal to the ecliptic plane. There are several methods how to do this including one with gravity assist maneuvers near Moon or use of the rocket engine for correction maneuvers, but the simplest – the search of an appropriate option within the family of possible transfer trajectories.
In the paper all these approaches are analyzed and it is shown that for standard scenario for them some difficulties do exist leading to the decrease the reliability of mission at large. The reason is that the thrust of the spacecraft rocket engines is too low, leading to burn durations that are too long.
For more practical approach, it is proposed to use the upper stage of the launcher for the maneuvers intended to decrease the amplitude of the orbit in the ecliptic pole direction. This leads to increasing the duration of spacecraft visibility to an acceptable level for the ground stations situated on the Russian territory. But the most promising and effective option is a single impulse trajectory with an optimal choice of the initial orbital state vector.
Also the problem of reaching the maximum amplitude of the orbit normal to the ecliptic, the “Z-amplitude”, is considered. This goal is to be reached for another project -Millimetron. This project goal is to build a space interferometer with very long base consisting of two telescopes: one in space near the [Sun-Earth L2] libration point and the other on the Earth’s surface.
It is shown that it is possible to put the spacecraft into an orbit with a Z-amplitude value of more than one million kilometers, practically with the same velocity impulse as for orbits with several times less Z-amplitude. The proposed method for this is the appropriate choice of the perigee position of the transfer orbit.
One of the key advances in genome assembly that has led to a significant improvement in contig lengths has been improved algorithms for utilization of paired reads (mate-pairs). While in most assemblers, mate-pair information is used in a post-processing step, the recently proposed Paired de Bruijn Graph (PDBG) approach incorporates the mate-pair information directly in the assembly graph structure. However, the PDBG approach faces difficulties when the variation in the insert sizes is high. To address this problem, we first transform mate-pairs into edge-pair histograms that allow one to better estimate the distance between edges in the assembly graph that represent regions linked by multiple mate-pairs. Further, we combine the ideas of mate-pair transformation and PDBGs to construct new data structures for genome assembly: pathsets and pathset graphs.
This volume presents new results in the study and optimization of information transmission models in telecommunication networks using different approaches, mainly based on theiries of queueing systems and queueing networks .
The paper provides a number of proposed draft operational guidelines for technology measurement and includes a number of tentative technology definitions to be used for statistical purposes, principles for identification and classification of potentially growing technology areas, suggestions on the survey strategies and indicators. These are the key components of an internationally harmonized framework for collecting and interpreting technology data that would need to be further developed through a broader consultation process. A summary of definitions of technology already available in OECD manuals and the stocktaking results are provided in the Annex section.