Search

Your search keyword '"Zhiltsov, N."' showing total 127 results
Start Over Author "Zhiltsov, N."
127 results on '"Zhiltsov, N."'

1. Effect of Locked MHD Modes on the Efficiency of Plasma Heating by the Neutral Beam Injection Method at the Globus-M2 Spherical Tokamak

Author

Petrov, Yu. V., Balachenkov, I. M., Bakharev, N. N., Varfolomeev, V. I., Voronin, A. V., Gusev, V. K., Zhiltsov, N. S., Kavin, A. A., Kiselev, E. O., Kurskiev, G. S., Minaev, V. B., Miroshnikov, I. V., Novokhatskii, A. N., Sakharnov, N. V., Skrekel, O. M., Solokha, V. V., Telnova, A. Yu., Tkachenko, E. E., Tokarev, V. A., Tolstyakov, S. Yu., Tukhmeneva, E. A., Khromov, N. A., Shchegolev, P. B., and Shulyatyev, K. D.

Published
2024
Full Text
View/download PDF

4. Set of Thomson Scattering Diagnostics for TRT

Author

Mukhin, E. E., Tolstyakov, S. Yu., Kurskiev, G. S., Zhiltsov, N. S., Ermakov, N. V., Tkachenko, E. E., Koval, A. N., Solovey, V. A., Aleksandrov, S. A., Nikolaev, A. V., Antropov, D. A., Bondar, A. V., Kedrov, I. V., Marchenko, T. A., Kornev, A. F., Makarov, A. M., Bogachev, D. L., Samsonov, D. S., Guk, E. G., Klimov, V. N., Smirnova, E. P., Sotnikov, A. V., Razdobarin, A. G., Bazhenov, A. N., Bocharov, I. V., Bocharnikov, V. A., Bukreev, I. M., Dmitriev, A. M., Elets, D. I., Tereshchenko, I. B., Varshavchik, L. A., Chernakov, An. P., Pankrat’ev, P. A., Marchii, G. V., Minbaev, M., Nikolaenko, K. O., Kungurtsev, N. A., Sakharov, N. V., Petrov, Yu. V., and Mokeev, A. N.

Published
2024
Full Text
View/download PDF

5. Distinctive Features of Measuring Te and ne Spatial Distributions in the Globus-M2 Spherical Tokamak Using Method of Thomson Scattering of Laser Radiation

Author

Zhiltsov, N. S., Kurskiev, G. S., Solovey, V. A., Tkachenko, E. E., Tolstyakov, S. Yu., Balachenkov, I. M., Bakharev, N. N., Varfolomeev, V. I., Voronin, A. V., Gusev, V. K., Goryainov, V. Yu., D’yachenko, V. V., Ermakov, N. V., Kavin, A. A., Kiselev, E. O., Konovalov, A. N., Krikunov, S. V., Minaev, V. B., Mineev, A. B., Miroshnikov, I. V., Mukhin, E. E., Novokhatsky, A. N., Patrov, M. I., Petrov, Yu. V., Ponomarenko, A. M., Sakharov, N. V., Skrekel’, O. M., Solokha, V. V., Telnova, A. Yu., Tokarev, V. A., Tukhmeneva, E. A., Filippov, S. V., Khromov, N. A., Shchegolev, P. B., Shulyatiev, K. D., and Yashin, A. Yu.

Published
2024
Full Text
View/download PDF

9. Diagnostic Complex of the Globus-M2 Spherical Tokamak

Author

Petrov, Yu. V., Bagryansky, P. A., Balachenkov, I. M., Bakharev, N. N., Brunkov, P. N., Varfolomeev, V. I., Voronin, A. V., Gusev, V. K., Goryainov, V. A., Dyachenko, V. V., Ermakov, N. V., Zhilin, E. G., Zhiltsov, N. S., Ivanenko, S. V., Il’yasova, M. V., Kavin, A. A., Kiselev, E. O., Konovalov, A. N., Krikunov, S. V., Kurskiev, G. S., Melnik, A. D., Minaev, V. B., Mineev, A. B., Miroshnikov, I. V., Mukhin, E. E., Novokhatsky, A. N., Petrov, A. V., Ponomarenko, A. M., Sakharov, N. V., Skrekel, O. M., Solomakhin, A. E., Solokha, V. V., Telnova, A. Yu., Tkachenko, E. E., Tokarev, V. A., Tolstyakov, S. Yu., Tukhmeneva, E. A., Khil’kevich, E. M., Khromov, N. A., Chernyshev, F. V., Shevelev, A. E., Shchegolev, P. B., Shulyat’ev, K. D., and Yashin, A. Yu.

Published
2023
Full Text
View/download PDF

10. Divertor Thomson Scattering on Globus-M2

Author

Ermakov, N. V., Zhiltsov, N. S., Kurskiev, G. S., Mukhin, E. E., Tolstyakov, S. Yu., Tkachenko, E. E., Solovey, V. A., Bocharov, I. V., Dolgova, K. V, Kavin, A. A., Koval, A. N., Nikolaenko, K. O., Novokhatsky, A. N., Petrov, Yu. V., Rozhansky, V. A., Sakharov, N. V., and Senichenkov, I. Yu.

Published
2023
Full Text
View/download PDF

11. Synthetic Diagnostic of Spectra of Charge-Exchange Atoms for Analysis of Influence of the MHD Instability on Fast-Particle Confinement in Spherical Tokamaks Globus-M/M2

Author

Kiselev, E. O., Balachenkov, I. M., Bakharev, N. N., Varfolomeev, V. I., Voronin, A. V., Goryainov, V. Yu., Gusev, V. K., Zhiltsov, N. S., Zenkova, O. A., Kurskiev, G. S., Melnik, A. D., Minaev, V. B., Miroshnikov, I. V., Patrov, M. I., Petrov, Yu. V., Sakharov, N. V., Skrekel, O. M., Telnova, A. Yu., Tkachenko, E. E., Tokarev, V. A., Tukhmeneva, E. A., Khromov, N. A., Chernyshov, F. V., and Shchegolev, P. B.

Published
2023
Full Text
View/download PDF

12. Free-Boundary Plasma Equilibrium Computation in Spherical Globus-M2 Tokamak by Means of the pyGSS Code

Author

Kiselev, E. O., Balachenkov, I. M., Bakharev, N. N., Varfolomeev, V. I., Gusev, V. K., Zhiltsov, N. S., Zenkova, O. A., Kavin, A. A., Kurskiev, G. S., Minaev, V. B., Miroshnikov, I. V., Patrov, M. I., Petrov, Yu. V., Sakharov, N. V., Skrekel, O. M., Solokha, V. V., Telnova, A. Yu., Tkachenko, E. E., Tokarev, V. A., Tukhmeneva, E. A., Khromov, N. A., and Shchegolev, P. B.

Published
2023
Full Text
View/download PDF

15. First Experiments on Reduction the Heat Load on the Divertor Plates of the Globus-M2 Tokamak Using Nitrogen Seeding and Their Comparison with Simulation Results

Author

Khromov, N. A., Bakharev, N. N., Vekshina, E. O., Gusev, V. K., Dolgova, K. V., Zhiltsov, N. S., Kiselev, E. O., Kurskiev, G. S., Minaev, V. B., Miroshnikov, I. V., Molchanov, P. A., Novokhatsky, A. N., Petrov, Yu. V., Rozhansky, V. A., Sakharov, N. V., Telnova, A. Yu., Timokhin, V. M., Tkachenko, E. E., Tokarev, V. A., Tukhmeneva, E. A., and Shchegolev, P. B.

Published
2023
Full Text
View/download PDF

16. Features of Plasma Disruption in the Globus-M2 Spherical Tokamak

Author

Sakharov, N. V., Kavin, A. A., Mineev, A. B., Bakharev, N. N., Bondarchuk, E. N., Gusev, V. K., Zhiltsov, N. S., Kiselev, E. O., Kurskiev, G. S., Minaev, V. B., Petrov, Yu. V., Rodin, I. Yu., Skrekel, O. M., Telnova, A. Yu., Tkachenko, E. E., Tokarev, V. A., Tukhmeneva, E. A., and Shchegolev, P. B.

Published
2023
Full Text
View/download PDF

17. Classification of Edge Instabilities at Globus-M2 Tokamak

Author

Solokha, V. V., Kurskiev, G. S., Yashin, A. Yu., Balachenkov, I. M., Varfolomeev, V. I., Voronin, A. V., Gusev, V. K., Goryainov, V. Yu., Dyachenko, V. V., Zhiltsov, N. S., Kiselev, E. O., Minaev, V. B., Novokhatsky, A. N., Petrov, Yu. V., Ponomarenko, A. M., Sakharov, N. V., Telnova, A. Yu., Tkachenko, E. E., Tokarev, V. A., Tolstyakov, S. Yu., Tukhmeneva, E. A., Khromov, N. A., and Shchegolev, P. B.

Published
2023
Full Text
View/download PDF

18. Hot Ion Mode in the Globus-M2 Spherical Tokamak

Author

Kurskiev, G. S., Sakharov, N. V., Gusev, V. K., Minaev, V. B., Miroshnikov, I. V., Petrov, Yu. V., Telnova, A. Yu., Bakharev, N. N., Kiselev, E. O., Zhiltsov, N. S., Shchegolev, P. B., Balachenkov, I. M., Varfolomeev, V. I., Voronin, A. V., Goryainov, V. Yu., Dyachenko, V. V., Zhilin, E. G., Iliasova, M. V., Kavin, A. A., Konovalov, A. N., Krikunov, S. V., Lobanov, K. M., Melnik, A. D., Mineev, A. B., Novokhatsky, A. N., Patrov, M. I., Petrov, A. V., Ponomarenko, A. M., Skrekel’, O. M., Solovei, V. A., Solokha, V. V., Tkachenko, E. E., Tokarev, V. A., Tolstyakov, S. Yu., Tukhmeneva, E. A., Khilkevitch, E. M., Khromov, N. A., Chernyshev, F. V., Shevelev, A. E., Shulyat’ev, K. D., and Yashin, A. Yu.

Published
2023
Full Text
View/download PDF

20. Parametric Studies of a Globus-3 Spherical Tokamak with Various Options of Electromagnetic Systems Based on Copper Alloys Using the GLOBSYS Code

Author

Mineev, A. B., Minaev, V. B., Sakharov, N. V., Bakharev, N. N., Bondarchuk, E. N., Voronova, A. A., Glushaev, A. M., Grigoriev, S. A., Gusev, V.K., Zhiltsov, N. S., Zapretilina, E. R., Kavin, A. A., Kiselev, E. O., Konin, A. Yu., Kudriavtseva, A. M., Kurskiev, G. S., Labusov, A. N., Petrov, Yu. V., Rodin, I. Yu., Tanchuk, V. N., Tel’nova, A. Yu., Trofimov, V. A., and Filatov, O. G.

Published
2022
Full Text
View/download PDF

21. Crystalline structure and XMCD studies of Co40Fe40B20 grown on Bi2Te3, BiTeI and Bi2Se3

Author

Kaveev, A. K., Sokolov, N. S., Suturin, S. M., Zhiltsov, N. S., Golyashov, V. A., Tereshchenko, O. E., Prosvirin, I. P., Kokh, K. A., and Sawada, M.

Subjects
Condensed Matter - Materials Science
Abstract

Epitaxial films of Co40Fe40B20 (further - CoFeB) were grown on Bi2Te3(001) and Bi2Se3(001) substrates by laser molecular beam epitaxy (LMBE) technique at 200-400C. Bcc-type crystalline structure of CoFeB with (111) plane parallel to (001) plane of Bi2Te3 was observed, in contrast to polycrystalline CoFeB film formed on Bi2Se3(001) at RT using high-temperature seeding layer. Therefore, structurally ordered ferromagnetic thin films were obtained on the topological insulator surface for the first time. Using high energy electron diffraction (RHEED) 3D reciprocal space mapping, epitaxial relations of main crystallographic axes for the CoFeB/ Bi2Te3 heterostructure were revealed. MOKE and AFM measurements showed the isotropic azimuthal in-plane behavior of magnetization vector in CoFeB/ Bi2Te3, in contrast to 2nd order magnetic anisotropy seen in CoFeB/Bi2Se3. XPS measurements showed more stable behavior of CoFeB grown on Bi2Te3 to the oxidation, in compare to CoFeB grown on Bi2Se3. XAS and XMCD measurements of both concerned nanostructures allowed calculation of spin and orbital magnetic moments for Co and Fe. Additionally, crystalline structure and XMCD response of the CoFeB/BiTeI and Co55Fe45/BiTeI systems were studied, epitaxial relations of main crystallographic axes were found, and spin and orbital magnetic moments were calculated., Comment: 9 pages, 12 figures, 1 table

Published
2018

24. Distinctive Features of Measuring Te and ne Spatial Distributions in the Globus-M2 Spherical Tokamak Using Method of Thomson Scattering of Laser Radiation.

Author

Zhiltsov, N. S., Kurskiev, G. S., Solovey, V. A., Tkachenko, E. E., Tolstyakov, S. Yu., Balachenkov, I. M., Bakharev, N. N., Varfolomeev, V. I., Voronin, A. V., Gusev, V. K., Goryainov, V. Yu., D'yachenko, V. V., Ermakov, N. V., Kavin, A. A., Kiselev, E. O., Konovalov, A. N., Krikunov, S. V., Minaev, V. B., Mineev, A. B., and Miroshnikov, I. V.

Subjects
*THOMSON scattering, *LASER beams, *TOKAMAKS, *MAGNETIC reconnection, *TEMPERATURE distribution, *ELECTRON temperature
Abstract

The results of measuring the electron temperature and density spatial distributions in plasma of the Globus-M2 tokamak using the Thomson scattering diagnostics are presented. The diagnostics provides measurements throughout the entire tokamak discharge, starting from time of gas breakdown. The Thomson scattering data were analyzed in order to determine the positions of the last closed flux surface, the plasma magnetic axis, and the radius of inversion during the saw-tooth oscillations. The results of measurements performed during the internal reconnection of magnetic field lines are presents, as well as the dynamics of spatial distributions of electron temperature, density and pressure during the plasma transition to the H-mode. The results of measuring the electron temperature distribution in the scrape-off layer using the Thomson scattering diagnostics are also presented for distances up to 4 cm outside the last closed flux surface. [ABSTRACT FROM AUTHOR]

Published
2024
Full Text
View/download PDF

25. The investigation of edge-localized modes on the Globus-M2 tokamak using Doppler backscattering.

Author

Ponomarenko, A., Gusev, V., Kiselev, E., Kurskiev, G., Minaev, V., Petrov, A., Petrov, Y., Sakharov, N., Solokha, V., Teplova, N., Shchegolev, P., Yashin, A., and Zhiltsov, N.

Subjects
TOKAMAKS, BACKSCATTERING, PLASMA turbulence, PLASMA boundary layers, DRIED blood spot testing
Abstract

The first results of investigation of edge localized modes (ELMs) in the Globus-M2 tokamak using the Doppler backscattering method are presented in this paper. Specifically, ELMs that are initiated by sawtooth crashes in the H-mode are discussed. The goal of this paper is study plasma turbulence behaviour during ELMs and to showcase what ELM characteristics can be obtained using Doppler backscattering (DBS). An increase of the poloidal rotation velocity during an ELM burst and a decrease in the inter-ELM periods was observed. The effect of ELMs on the plasma turbulence was investigated and estimated to span around 6 cm inside the separatrix. This is to do with the fact that the sawtooth crashes which are responsible for initiating the ELMs take place in the core plasma. Additional experiments with standard reflectometry indicate that ELMs develop 3 cm inside the separatrix where the pedestal region is believed to be in Globus-M2. The direction of the expansion of the ELMs from the inner plasma region to the edge was determined and the velocity was estimated to be around 8 km s−1. During a single ELM burst a series of filament structures were found in the peripheral DBS channels. In an attempt to understand the processes involved modelling of the reaction of the DBS signals to filaments was done using the BOUT ++ and IPF-FD3D full-wave codes, and the cases for both linear and nonlinear scattering were considered. The results show that the presence of nonlinear scattering during ELMs can lead to an overestimation of the measured velocity values in the region of filament existence near the separatrix. [ABSTRACT FROM AUTHOR]

Published
2024
Full Text
View/download PDF

26. Experiment with nitrogen seeding at the Globus-M2 tokamak

Author

Vekshina, E., primary, Dolgova, K., additional, Rozhansky, V., additional, Kaveeva, E., additional, Senichenkov, I., additional, Molchanov, P., additional, Timokhin, V., additional, Khromov, N., additional, Zhiltsov, N., additional, Bakharev, N., additional, Kiselev, E., additional, and Tuhmeneva, E., additional

Published
2023
Full Text
View/download PDF

34. Electron temperature measurements at the Globus-M2 tokamak using multi-laser Thomson scattering

Author

null Chernakov P. V., null Tolstyakov S. Yu, null Tkachenko E. E., null Solovey V. A., null Sakharov N. V., null Petrov Yu. V., null Mukhin E. E., null Makarov A. M., null Kornev A. F., null Koval A. N., null Zhiltsov N. S., and null Kurskiev G. S.

Abstract

Diagnostics of the plasma electron component by the method of Thomson scattering Te(R,t) of laser radiation makes it possible to reliably measure the spatial distributions of the electron temperature and density. One of the obstacles to the implementation of TS diagnostics in thermonuclear reactors is the distortion of the spectral characteristics of the optical system due to radiation-induced absorption and contamination of optical elements with erosion products of the first wall. As a consequence, the reliability of measurements by the TS method will decrease over time. The paper describes the method of multi-laser Thomson scattering, which will solve this problem. The results of the first experiments on the Globus-M2 tokamak are also presented. Keywords: plasma diagnostic, tokamak, thomson scattering, laser diagnostic, spectroscopy.

Published
2022

35. Influence of increased magnetic field on Alfvén eigenmodes on upgraded spherical tokamak Globus-M2

Author

Balachenkov, I M, primary, Petrov, Yu V, additional, Gusev, V K, additional, Bakharev, N N, additional, Bulanin, V V, additional, Varfolomeev, V I, additional, Dyachenko, V V, additional, Zhiltsov, N S, additional, Kiselev, E O, additional, Konovalov, A N, additional, Krikunov, S V, additional, Kurskiev, G S, additional, Minaev, V B, additional, Patrov, M I, additional, Petrov, A V, additional, Ponomarenko, A M, additional, Sakharov, N V, additional, Telnova, A Yu, additional, Shchegolev, P B, additional, and Yashin, A Yu, additional

Published
2020
Full Text
View/download PDF

36. Parameterized fielded term dependence models for ad-hoc entity retrieval from knowledge graph

Author

Nikolaev F., Kotov A., and Zhiltsov N.

Subjects
Knowledge graph, Entity retrieval, Structured document retrieval, Feature-based models, Learning-to-rank models
Abstract

© 2016 ACM.Accurate projection of terms in free-text queries onto structured entity representations is one of the fundamental problems in entity retrieval from knowledge graph. In this paper, we demonstrate that existing retrieval models for ad-hoc structured and unstructured document retrieval fall short of addressing this problem, due to their rigid assumptions. According to these assumptions, either all query concepts of the same type (unigrams and bigrams) are projected onto the fields of entity representations with identical weights or such projection is determined based only on one simple statistic, which makes it sensitive to data sparsity. To address this issue, we propose the Parametrized Fielded Sequential Dependence Model (PFSDM) and the Parametrized Fielded Full Dependence Model (PFFDM), two novel models for entity retrieval from knowledge graphs, which infer the user's intent behind each individual query concept by dynamically estimating its projection onto the fields of structured entity representations based on a small number of statistical and linguistic features. Experimental results obtained on several publicly available benchmarks indicate that PFSDM and PFFDM consistently outperform state-of-the-art retrieval models for the task of entity retrieval from knowledge graph.

Published
2016

37. Fielded sequential dependence model for ad-hoc entity retrieval in the web of data

Author

Zhiltsov N., Kotov A., and Nikolaev F.

Subjects
Entity retrieval, Term dependence, InformationSystems_INFORMATIONSTORAGEANDRETRIEVAL, Knowledge graphs
Abstract

Previously proposed approaches to ad-hoc entity retrieval in the Web of Data (ERWD) used multi-fielded representation of entities and relied on standard unigram bag-of-words retrieval models. Although retrieval models incorporating term dependencies have been shown to be significantly more effective than the unigram bag-of-words ones for ad hoc document retrieval, it is not known whether accounting for term dependencies can improve retrieval from the Web of Data. In this work, we propose a novel retrieval model that incorporates term dependencies into structured document retrieval and apply it to the task of ERWD. In the proposed model, the document field weights and the relative importance of unigrams and bigrams are optimized with respect to the target retrieval metric using a learning-to-rank method. Experiments on a publicly available benchmark indicate significant improvement of the accuracy of retrieval results by the proposed model over state-of-the-art retrieval models for ERWD.

Published
2015

38. OntoMathPRO ontology: A linked data hub for mathematics

Author

Nevzorova O., Zhiltsov N., Kirillovich A., and Lipachev E.

Subjects
Ontology engineering, Linked Open Data, Mathematical knowledge
Abstract

© Springer International Publishing Switzerland 2014. In this paper, we present an ontology of mathematical knowledge concepts that covers a wide range of the fields of mathematics and introduces a balanced representation between comprehensive and sensible models. We demonstrate the applications of this representation in information extraction, semantic search, and education. We argue that the ontology can be a core of future integration of math-aware data sets in the Web of Data and, therefore, provide mappings onto relevant datasets, such as DBpedia and ScienceWISE.

Published
2014

39. Bringing math to LOD: A semantic publishing platform prototype for scientific collections in mathematics

Author

Nevzorova O., Zhiltsov N., Zaikin D., Zhibrik O., Kirillovich A., Nevzorov V., and Birialtsev E.

Subjects
Linked Data, Ontology Extraction, Ontology Engineering
Abstract

We present our work on developing a software platform for mining mathematical scholarly papers to obtain a Linked Data representation. Currently, the Linking Open Data (LOD) cloud lacks up-to-date and detailed information on professional level mathematics. To our mind, the main reason for that is the absence of appropriate tools that could analyze the underlying semantics in mathematical papers and effectively build their consolidated representation. We have developed a holistic approach to analysis of mathematical documents, including ontology based extraction, conversion of the article body as well as its metadata into RDF, integration with some existing LOD data sets, and semantic search. We argue that the platform may be helpful for enriching user experience on modern online scientific collections. © 2013 Springer-Verlag.

Published
2013

40. Mathematical text collections: Annotation and application for search tasks

Author

Nevzorova O., Birialtcev E., and Zhiltsov N.

Subjects
mathematical collection, semantic annotation
Abstract

This paper analyzes two models: semantic annotation of mathematical texts and semantic searching for mathematical texts in a marked-up collection. It also presents the results of a series of experiments that were performed with a semantically annotated collection of scientific publications in the field of mathematics. © 2013 Allerton Press, Inc.

Published
2013

41. Improving entity search over linked data by modeling latent semantics

Author

Zhiltsov N. and Agichtein E.

Subjects
Learning to rank, Tensor factorization, Entity search
Abstract

Entity ranking has become increasingly important, both for retrieving structured entities and for use in general web search applications. The most common format for linked data, RDF graphs, provide extensive semantic structure via predicate links. While the semantic information is potentially valuable for effective search, the resulting adjacency matrices are often sparse, which introduces challenges for representation and ranking. In this paper, we propose a principled and scalable approach for integrating of latent semantic information into a learning-to-rank model, by combining compact representation of semantic similarity, achieved by using a modified algorithm for tensor factorization, with explicit entity information. Our experiments show that the resulting ranking model scales well to the graphs with millions of entities, and outperforms the state-of-the-art baseline on realistic Yahoo! SemSearch Challenge data sets. Copyright 2013 ACM.

Published
2013

42. Logical structure analysis of scientific publications in mathematics

Author

Solovyev V. and Zhiltsov N.

Subjects
document structure analysis, linked data, ontology
Abstract

Even though the Linking Open Data cloud is constantly growing, there is a serious lack of published data sets related to the domain of academic mathematics. At the same time, since most scholarly publications in mathematics are well-structured and conventional, it's promising to get their helpful detailed representation. The paper describes an approach to extracting and analyzing the structure of mathematical papers. We present the Mocassin ontology that is used by analysis algorithms and can be considered as an ontology of the structure of scholarly publications in mathematics. The proposed semantic model has been evaluated on a set of real mathematical papers and preliminary evaluation results are encouraging. Also we discuss potential applications of the model to specific information retrieval tasks including semantic search. © 2011 ACM.

Published
2011

43. Publishing math lecture notes as linked data

Author

David C., Kohlhase M., Lange C., Rabe F., Zhiltsov N., and Zholudev V.

Subjects
ComputingMilieux_COMPUTERSANDEDUCATION, ComputingMethodologies_DOCUMENTANDTEXTPROCESSING
Abstract

We mark up a corpus of LATEX lecture notes semantically and expose them as Linked Data in XHTML+MathML+RDFa. Our application makes the resulting documents interactively browsable for students. Our ontology helps to answer queries from students and lecturers, and paves the path towards an integration of our corpus with external sites. © 2010 Springer-Verlag.

Published
2010

44. The results of the first experimental campaign on the Globus-M2 spherical tokamak

Author

Minaev, V. B., Gusev, V. K., Petrov, Yu V., Sakharov, N. V., Varfolomeev, V. I., Bakharev, N. N., Balachenkov, I. M., Bulanin, V. V., Chernyshev, F. V., Dyachenko, V. V., Kurskiev, G. S., Shchegolev, P. B., Telnova, A. Yu, Kavin, A. A., Khromov, N. A., Kiselev, E. O., Krikunov, S. V., Konovalov, A. N., Korepanov, P. A., Melnik, A. D., Miroshnikov, I. V., Novokhatsky, A. N., Patrov, M. I., Petrov, A. V., Ponomarenko, A. M., Shikhovtsev, I. V., Shulyatiev, K. D., Tkachenko, E. E., Tokarev, V. A., Tolstyakov, S. Yu, Tukhmeneva, E. A., Goryainov, V. Yu, Iliasova, M. V., Khilkevitch, E. M., Nesenevich, V. G., Shevelev, A. E., Olga Skrekel, Voronin, A. V., Yashin, A. Yu, Zhilin, E. G., and Zhiltsov, N. S.

45. Parameterized fielded term dependence models for ad-hoc entity retrieval from knowledge graph

Author

Nikolaev F., Kotov A., Zhiltsov N., Nikolaev F., Kotov A., and Zhiltsov N.

Abstract

© 2016 ACM.Accurate projection of terms in free-text queries onto structured entity representations is one of the fundamental problems in entity retrieval from knowledge graph. In this paper, we demonstrate that existing retrieval models for ad-hoc structured and unstructured document retrieval fall short of addressing this problem, due to their rigid assumptions. According to these assumptions, either all query concepts of the same type (unigrams and bigrams) are projected onto the fields of entity representations with identical weights or such projection is determined based only on one simple statistic, which makes it sensitive to data sparsity. To address this issue, we propose the Parametrized Fielded Sequential Dependence Model (PFSDM) and the Parametrized Fielded Full Dependence Model (PFFDM), two novel models for entity retrieval from knowledge graphs, which infer the user's intent behind each individual query concept by dynamically estimating its projection onto the fields of structured entity representations based on a small number of statistical and linguistic features. Experimental results obtained on several publicly available benchmarks indicate that PFSDM and PFFDM consistently outperform state-of-the-art retrieval models for the task of entity retrieval from knowledge graph.

46. Fielded sequential dependence model for ad-hoc entity retrieval in the web of data

Author

Zhiltsov N., Kotov A., Nikolaev F., Zhiltsov N., Kotov A., and Nikolaev F.

Abstract

Previously proposed approaches to ad-hoc entity retrieval in the Web of Data (ERWD) used multi-fielded representation of entities and relied on standard unigram bag-of-words retrieval models. Although retrieval models incorporating term dependencies have been shown to be significantly more effective than the unigram bag-of-words ones for ad hoc document retrieval, it is not known whether accounting for term dependencies can improve retrieval from the Web of Data. In this work, we propose a novel retrieval model that incorporates term dependencies into structured document retrieval and apply it to the task of ERWD. In the proposed model, the document field weights and the relative importance of unigrams and bigrams are optimized with respect to the target retrieval metric using a learning-to-rank method. Experiments on a publicly available benchmark indicate significant improvement of the accuracy of retrieval results by the proposed model over state-of-the-art retrieval models for ERWD.

47. Improving entity search over linked data by modeling latent semantics

Author

Zhiltsov N., Agichtein E., Zhiltsov N., and Agichtein E.

Abstract

Entity ranking has become increasingly important, both for retrieving structured entities and for use in general web search applications. The most common format for linked data, RDF graphs, provide extensive semantic structure via predicate links. While the semantic information is potentially valuable for effective search, the resulting adjacency matrices are often sparse, which introduces challenges for representation and ranking. In this paper, we propose a principled and scalable approach for integrating of latent semantic information into a learning-to-rank model, by combining compact representation of semantic similarity, achieved by using a modified algorithm for tensor factorization, with explicit entity information. Our experiments show that the resulting ranking model scales well to the graphs with millions of entities, and outperforms the state-of-the-art baseline on realistic Yahoo! SemSearch Challenge data sets. Copyright 2013 ACM.

48. Logical structure analysis of scientific publications in mathematics

Author

Solovyev V., Zhiltsov N., Solovyev V., and Zhiltsov N.

Abstract

Even though the Linking Open Data cloud is constantly growing, there is a serious lack of published data sets related to the domain of academic mathematics. At the same time, since most scholarly publications in mathematics are well-structured and conventional, it's promising to get their helpful detailed representation. The paper describes an approach to extracting and analyzing the structure of mathematical papers. We present the Mocassin ontology that is used by analysis algorithms and can be considered as an ontology of the structure of scholarly publications in mathematics. The proposed semantic model has been evaluated on a set of real mathematical papers and preliminary evaluation results are encouraging. Also we discuss potential applications of the model to specific information retrieval tasks including semantic search. © 2011 ACM.

49. Mathematical text collections: Annotation and application for search tasks

Author

Nevzorova O., Birialtcev E., Zhiltsov N., Nevzorova O., Birialtcev E., and Zhiltsov N.

Abstract

This paper analyzes two models: semantic annotation of mathematical texts and semantic searching for mathematical texts in a marked-up collection. It also presents the results of a series of experiments that were performed with a semantically annotated collection of scientific publications in the field of mathematics. © 2013 Allerton Press, Inc.

50. OntoMathPRO ontology: A linked data hub for mathematics

Author

Nevzorova O., Zhiltsov N., Kirillovich A., Lipachev E., Nevzorova O., Zhiltsov N., Kirillovich A., and Lipachev E.

Abstract

© Springer International Publishing Switzerland 2014. In this paper, we present an ontology of mathematical knowledge concepts that covers a wide range of the fields of mathematics and introduces a balanced representation between comprehensive and sensible models. We demonstrate the applications of this representation in information extraction, semantic search, and education. We argue that the ontology can be a core of future integration of math-aware data sets in the Web of Data and, therefore, provide mappings onto relevant datasets, such as DBpedia and ScienceWISE.

Catalog

Books, media, physical & digital resources
See catalog results