Distributed integrated navigation systems for planetary defense against asteroids
The main objectives of this paper are to give an interdisciplinary overview of the current status of the research on planetary defense against asteroids, which is a real challenge, and consider technical proposals on the development of a multilevel planetary defense system based on modern space technologies, providing for the application of projectile asteroids to deflect target asteroids’ trajectories and distributed integrated navigation systems, the navigation equipment of which is supposed to be installed on many different objects. The composition of such navigation systems and their accuracies are discussed. This work is based on the results obtained by the international Research Laboratory of Space Research, Technologies, Systems and Processes , founded at Moscow Institute of Electronics and Mathematics (MIEM), Branch of Higher School of Economics (HSE) in 2011. The project was supported by the grant of the Government of the Russian Federation (2011–2013) [2, 3]. We have also used pioneering ideas from the course of lectures Models of planetary defense , prepared at the Department of Mechanics and Mathematical Modeling, MIEM NRU HSE in 2014 .
This paper presents how machine learning algorithms and methods of statistics can be implemented to data management in hybrid data storage systems. Basicly, two di↵erent storage types are used to store data in the hybrid data storage systems. Keeping low-frequenty used data on cheap and slow storages of type one and high-frequently used data on fast and expensive storages of type two helps to achieve optimal performance/cost ratio for the system. We use classification algorithms to estimate probability that the data will high-frequently used in future. Then, using the risks analysis we define where the data should be stored. We show how to estimate optimal number of replicas of the data using regression algorithms and Hidden Markov Model. Based on the probability, risks and the optimal nuber of data replicas our recommendation system finds optimal data distribution in the hybrid data storage system. We present the results of our method implementation in LHCb hybrid data storage.
Coordination of several distributed system components is an error-prone task, since interaction of several simple components can generate rather sophisticated behavior. Verification of such systems is very difficult or even impossible because of the so-called state space explosion problem, when the size of the system reachability set grows exponentially on the number of interacting agents. To overcome this problem several approaches to construct correct models of interacting agents in a compositional way were proposed in the literature. They define different properties and conditions to ensure correct behavior of interacting agents. Checking these conditions may be in its turn quite a problem. In this paper, we propose patterns for correct composition of component models. For justifying these patterns we use special net morphisms. However, to apply patterns the user does not need to be familiar with the underlying theory.
The annual ACM SIGMOD/PODS Conference is a leading international forum for database researchers, practitioners, developers, and users to explore cutting-edge ideas and results, and to exchange techniques, tools, and experiences. The conference includes a fascinating technical program with research and industrial talks, tutorials, demos, and focused workshops. It also hosts a poster session to learn about innovative technology, an industrial exhibition to meet companies and publishers, and a careers-in-industry panel with representatives from leading companies.
Explosive growth of raster data volumes in numerical simulations, remote sensing and other fields stimulate the development of new efficient data processing techniques. For example, in-situ approach queries data in diverse file formats avoiding time-consuming import phase. However, after data are read from file, their further processing always takes place with code developed almost from scratch. Standalone command line tools are one of the most popular ways for in-situ processing of raster files. Decades of development and feedback resulted in numerous feature-rich, elaborate, free and quality-assured tools mostly for a single machine. The paper reports current development state of ChronosServer – distributed system partially delegating in-situ raster processing to external tools. The new delegation approach is anticipated to readily provide rich collection of raster data operations at scale.
Proceedings of the International Astronautical Congress
The dynamics of a two-component Davydov-Scott (DS) soliton with a small mismatch of the initial location or velocity of the high-frequency (HF) component was investigated within the framework of the Zakharov-type system of two coupled equations for the HF and low-frequency (LF) fields. In this system, the HF field is described by the linear Schrödinger equation with the potential generated by the LF component varying in time and space. The LF component in this system is described by the Korteweg-de Vries equation with a term of quadratic influence of the HF field on the LF field. The frequency of the DS soliton`s component oscillation was found analytically using the balance equation. The perturbed DS soliton was shown to be stable. The analytical results were confirmed by numerical simulations.
By using superconducting quantum interference device (SQUID) magnetometry, we investigated anisotropic high-field (H less than or similar to 7T) low-temperature (10 K) magnetization response of inhomogeneous nanoisland FeNi films grown by rf sputtering deposition on Sitall (TiO2) glass substrates. In the grown FeNi films, the FeNi layer nominal thickness varied from 0.6 to 2.5 nm, across the percolation transition at the d(c) similar or equal to 1.8 nm. We discovered that, beyond conventional spin-magnetism of Fe21Ni79 permalloy, the extracted out-of-plane magnetization response of the nanoisland FeNi films is not saturated in the range of investigated magnetic fields and exhibits paramagnetic-like behavior. We found that the anomalous out-of-plane magnetization response exhibits an escalating slope with increase in the nominal film thickness from 0.6 to 1.1 nm, however, it decreases with further increase in the film thickness, and then practically vanishes on approaching the FeNi film percolation threshold. At the same time, the in-plane response demonstrates saturation behavior above 1.5-2T, competing with anomalously large diamagnetic-like response, which becomes pronounced at high magnetic fields. It is possible that the supported-metal interaction leads to the creation of a thin charge-transfer (CT) layer and a Schottky barrier at the FeNi film/Sitall (TiO2) interface. Then, in the system with nanoscale circular domains, the observed anomalous paramagnetic-like magnetization response can be associated with a large orbital moment of the localized electrons. In addition, the inhomogeneous nanoisland FeNi films can possess spontaneous ordering of toroidal moments, which can be either of orbital or spin origin. The system with toroidal inhomogeneity can lead to anomalously strong diamagnetic-like response. The observed magnetization response is determined by the interplay between the paramagnetic-and diamagnetic-like contributions.
Radiation conditions are described for various space regions, radiation-induced effects in spacecraft materials and equipment components are considered and information on theoretical, computational, and experimental methods for studying radiation effects are presented. The peculiarities of radiation effects on nanostructures and some problems related to modeling and radiation testing of such structures are considered.
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.