National Research University – Higher School of Economics

About: National Research University – Higher School of Economics is a education organization based out in Moscow, Russia. It is known for research contribution in the topics: Population & Computer science. The organization has 12873 authors who have published 23376 publications receiving 256396 citations.

Universal dependencies for Turkish

Abstract: The Universal Dependencies (UD) project was conceived after the substantial recent interest in unifying annotation schemes across languages. With its own annotation principles and abstract inventory for parts of speech, morphosyntactic features and dependency relations, UD aims to facilitate multilingual parser development, cross-lingual learning, and parsing research from a language typology perspective. This paper presents the Turkish IMST-UD Treebank, the first Turkish treebank to be in a UD release. The IMST-UD Treebank was automatically converted from the IMST Treebank, which was also recently released. We describe this conversion procedure in detail, complete with mapping tables. We also present our evaluation of the parsing performances of both versions of the IMST Treebank. Our findings suggest that the UD framework is at least as viable for Turkish as the original annotation framework of the IMST Treebank.

Improvements to MCS algorithm for the maximum clique problem

Abstract: In this paper we present improvements to one of the most recent and fastest branch-and-bound algorithm for the maximum clique problem--MCS algorithm by Tomita et al. (Proceedings of the 4th international conference on Algorithms and Computation, WALCOM'10, pp. 191---203, 2010). The suggested improvements include: incorporating of an efficient heuristic returning a high-quality initial solution, fast detection of clique vertices in a set of candidates, better initial colouring, and avoiding dynamic memory allocation. Our computational study shows some impressive results, mainly we have solved p_hat1000-3 benchmark instance which is intractable for MCS algorithm and got speedups of 7, 3000, and 13000 times for gen400_p0.9_55, gen400_p0.9_65, and gen400_p0.9_75 instances correspondingly.

Indigenous Peoples of Northern Russia: Anthropology and Health

Abstract: (2007). Indigenous Peoples of Northern Russia: Anthropology and Health. International Journal of Circumpolar Health: Vol. 66, No. sup1, pp. 1-184.

Anharmonicity Extends Carrier Lifetimes in Lead Halide Perovskites at Elevated Temperatures.

Abstract: Lead halide perovskites constitute a very promising class of materials for a broad range of solar and optoelectronic applications. Perovskites exhibit many unusual properties, and recent experiments demonstrate an unusual temperature dependence of charge carrier lifetimes. Focusing on the all-inorganic CsPbBr3, and using a combination of ab initio nonadiabatic molecular dynamics and time-domain density functional theory, we demonstrate that the unconventional behavior arises because of a highly anharmonic nature of atomic motions in perovskites. As temperature increases, perovskite structure undergoes a notable deformation, reflected in tilting of octahedral units, and experiences large-scale anharmonic movements away from the equilibrium geometry. As a result, the electronic energy gap increases, and phonon-induced loss of coherence within the electronic subsystem accelerates. These two factors slow down nonradiative electron-hole recombination, which constitutes the main limitation on efficiencies of perovskite solar, optical, and electronic devices. The increase of charge carrier lifetimes with temperature is particularly beneficial in applications, because materials heat up, for instance, from sunlight during solar energy harvesting. The behavior of the all-inorganic halide perovskite investigated here is different from that of hybrid organic-inorganic perovskites, which exhibit additional disorder associated with reorientations of the asymmetric organic cations. The reported simulations generate an in-depth understanding of the unusual properties of inorganic perovskites, relevant for photocatalytic, photovoltaic, electronic, and optical applications.

Undistinguishing statistics of objectively distinguishable objects: Thermodynamics and superfluidity of classical gas

Abstract: In the present paper, we describe an approach to thermodynamics that does not involve Bogolyubov chains or Gibbs ensembles. We present isotherms, isochores, and isobars of various pure gases, as well as binodals, i.e., lines along which gas becomes liquid, and spinodals (endpoints of isotherms). We study supercritical phenomena for values of temperature and pressure above the critical ones. A lot of attention is paid to the region of negative pressures. The superfluid component for supercritical phenomena is described, as well as the thermodynamics of nanostructures and superfluidity in nanotubes.