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2021 Ivannikov Ispras Open Conference, ISPRAS 2021

作者： Krichanov, Mikhail Cheptsov, Vitaly Ivannikov Institute For System Programming Of The Russian Academy Of Sciences Moscow Russia

ISBN: (纸本)9781665423304

The Unified Extensible Firmware Interface (UEFI) is a standardised interface between the firmware and the oper-ating system used in all x86-based platforms over the past ten years. A side effect of the transition from conventional BIOS implementations to more complex and flexible implementations based on the UEFI was that it became easier for the malware to target BIOS in a widespread fashion, as these BIOS implementations are based on a common specification. This paper introduces Amaranth project - a solution to some of the contemporary security issues related to UEFI firmware. In this work we focused our attention on virtual machines as it allowed us to simplify the development of secure UEFI firmware. Security hardening of our firmware is achieved through several techniques, the most important of which are an operating system integrity checking mechanism (through snapshots) and overall firmware size reduction. © 2021 IEEE.

关键词： Firmware

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Innovative methods and measures in overlapping community detection

Innovative methods and measures in overlapping community det...

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International Workshop on Experimental Economics and Machine Learning 2012, EEML 2012 - In Conjunction with the 10th International Conference on Formal Concept Analysis, ICFCA 2012

作者： Buzun, Nazar Korshunov, Anton Institute for System Programming Russian Academy of Sciences Moscow 109004 Russia

Cluster structure is one of the main features of social graphs. Many algorithms have been proposed in recent years that are capable of revealing fuzzy communities. But a lot of them tend to degrade in some special cases, for example when nodes assigned to more than two groups. Taking into account that such highly overlapping membership is rather common for many social networks, it becomes obvious that there is a need for flexible techniques and detecting the scope of their effective applicability for various network configuration parameters. This article focuses on the resistance to cluster's growth intersection with emphasis on local fitness function's optimization. The testing of the modern fuzzy clustering methods and generalized classical approaches is performed. Depending on the scale of fuzziness the conclusion is provided about the applicability of certain algorithm classes with common methodology and their representatives.

关键词： Fuzzy clustering

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Specializing PostgreSQL Expression Interpreter with Code Annotations

Specializing PostgreSQL Expression Interpreter with Code Ann...

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2021 Ivannikov Ispras Open Conference, ISPRAS 2021

作者： Sharygin, Eugene Pantilimonov, Michael Buchatskiy, Ruben Ivannikov Institute For System Programming Of The Russian Academy Of Sciences Moscow Russia

ISBN: (纸本)9781665423304

Vast majority of execution engines are first im-plemented as interpreters. Once they reach maturity and gain audience authors strive to improve performance by utilizing static or JIT compilation techniques. The latter helps to achieve the goal but at the expense of increased maintenance costs as source code splits into two loosely connected components. One solution to this problem is a program specialization method that utilizes existing interpreter's code and semi-automatically generates a compiler. In this paper we apply program specialization to the in-terpreter of the language of SQL expressions in PostgreSQL and show how the results compare against both the original interpreter and the built-in LLVM-based just-in-time compiler. © 2021 IEEE.

关键词： Database systems

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Spectral asymmetry effect in terahertz generation by two-color ionizing femtosecond pulses

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Physical Review A 2025年第2期111卷 023508-023508页

作者： Zhiwen Zhang Vasily A. Kostin Alexander A. Silaev Zefu Liu Shixiang Wang Chenhui Lu Zhengquan Fan Yi Liu Shanghai Key Lab of Modern Optical System University of Shanghai for Science and Technology Shanghai 200093 China Gaponov-Grekhov Institute of Applied Physics of the Russian Academy of Sciences Nizhny Novgorod 603950 Russia Department of Control Theory Lobachevsky State University of Nizhny Novgorod Nizhny Novgorod 603022 Russia Department of Electrodynamics Lobachevsky State University of Nizhny Novgorod Nizhny Novgorod 603022 Russia School of Mechanical and Automotive Engineering Shanghai University of Engineering Science Shanghai 201620 China CAS Center for Excellence in Ultra-Intense Laser Science Shanghai 201800 China

Ultrabroadband intense terahertz (THz) radiation generated by two-color femtosecond pulses is a promising tool for applications in many areas involving linear and nonlinear terahertz spectroscopy and light-matter interactions. The essential challenge is to understand and control the THz spectrum in order to optimize it for specific applications. Here we study the frequency-dependent modulation of the THz spectrum with the relative phase between the second-harmonic and fundamental-field components of the linearly polarized femtosecond pulse. Analytical consideration reveals the physical reason for the suppression of the spectral modulation, which is local (induced by the local ionization dynamics and electron motion and not related to propagation effects such as phase slippage) and coherent (associated only with the phase-dependent coherent THz waveforms). The spectral modulation is sensitive to the frequency detuning, both its absolute value and the sign. Having this asymmetric dependence on the detuning, the suppressed modulation can be observed even in commensurate two-color pulses with the effect enhanced additionally by the ionization blueshift. The theoretical findings are confirmed by the experiment, where we employed chirped two-color pulses with a variable time delay between their components, effectively enabling a scan over the detuning. The obtained results show that not only the THz yield but also the spectral shape can be effectively controlled by the relative phase and may be very sensitive to a small frequency detuning arising naturally during two-color pulse propagation.

关键词： Terahertz spectroscopy

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Using algebraic models of programs for detecting metamorphic malwares

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Journal of Mathematical sciences 2011年第5期172卷 740-750页

作者： Podlovchenko, R.I. Kuzyurin, N.N. Shcherbina, V.S. Zakharov, V.A. Moscow State University Moscow Russian Federation Institute for System Programming Russian Academy of Sciences Moscow Russian Federation

Polymorphic and metamorphic viruses are the most sophisticated malicious programs that give a lot of trouble to virus scanners. Each time when these viruses infect new executables or replicate themselves, they completely modify (obfuscate) their signature to avoid being detected. This contrivance poses a serious threat to antivirus software that relies on classical virus-detection techniques: such viruses do not have any stable specific sequence of instructions that one looks for. In the ultimate case, the only characteristic that remains invariable for all generations of the same virus is their functionality (semantics). To all appearance, the only way to detect for sure a metamorphic malicious code is to look for a pattern that has the same semantics as (i.e., equivalent to) some representative sample of the virus. Thus, metamorphic virus detection is closely related to the equivalence-checking problem for programs. In this paper, we outline some new automata-theoretic framework for the designing of virus detectors. Our approach is based on the equivalence-checking techniques in algebraic models of sequential programs. An algebraic model of programs is an abstract model of computation, where programs are viewed as finite automata operating on Kripke structures. Models of this kind make it possible to focus on those properties of program instructions that are widely used in obfuscating transformations. We give a survey (including the latest results) on the complexity of equivalence-checking problem in various algebraic models of programs and estimate thus the resilience of some obfuscating transformation commonly employed by metamorphic viruses. © 2011 Springer science+Business Media, Inc.

关键词： MALWARE (Computer software) COMPUTER software COMPUTER viruses MATHEMATICAL models ALGEBRA SCANNING systems

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Directed Generation of Test Data for Static Semantics Checker

Directed Generation of Test Data for Static Semantics Checke...

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作者： Arkhipova, M.V. Zelenov, S.V. Institute for System Programming of the Russian Academy of Sciences Russia

ISBN: (纸本)3540884785

We present an automatic method, named SemaTESK, for generation of test sets for a translator front end. We focus on the validation and verification of static semantics checker. Most the know methods for semantics test generation produce test suites by filtering a pre-generated set of random texts in the target language. In contrast, SemaTESK allows to generate tests for context conditions directly. It significantly reduces generation time and allows reaching completeness criteria defined in the paper. The presented method to specify static semantics allows to formalize informal requirements described in normative documents (e.g. standard). The method includes SRL notation for compact formal specification of context conditions and STG tool for efficient generation of test suite from SRL specification. The SemaTESK method has been used in a number of projects, including testing static semantics checkers of C and Java. © Springer-Verlag Berlin Heidelberg 2008.

关键词： Formal specification

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Mathematical Model of Gas Dilution in Two Phases Flows of Fluid and Gas 4

Mathematical Model of Gas Dilution in Two Phases Flows of Fl...

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4th International Conference on Supercomputer Technologies of Mathematical Modelling, SCTeMM 2019

作者： Levin, Mikhail P. Ivannikov Institute for System Programming of the Russian Academy of Sciences Moscow109004 Russia

Various models of solubility of gas in two-phase ows of gas and liquid are considered. Such phenomena play an important role in various technical devices especially at modern nuclear power plants. Mathematical models of bubble ows with gas dissolution, gas phase model, and model of liquid phase dissolution were considered and discussed. © Published under licence by IOP Publishing Ltd.

关键词： Gases

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On Solutions to Problems of Bottom Deformations with Allowance for Their Self-Similarity

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Power Technology and Engineering 2024年第4期58卷 611-616页

作者： Petrov, A.G. Potapov, I.I. Epikhin, A.S. Ishlinsky Institute for Problems of Mechanics Russian Academy of Sciences Moscow Russia Khabarovsk Federal Research Center Computing Center Far East Branch of the Russian Academy of Sciences Khabarovsk Russia Ivannikov Institute for System Programming Russian Academy of Sciences Moscow Russia

A method for establishing a self-similar dependence of the bottom surface on time and spatial coordinate is proposed. The mean bottom tangential stresses are determined for a series of self-similar shapes of the bottom to then calculate the rates of change in the lengths and amplitudes of the bottom waves. Comparison with experimental data and numerical solutions shows that the error of the solution does not exceed several percent and that the computation time is shorter by a factor of 25 to 30 than that of conventional evolutionary computation. © Springer science+Business Media, LLC, part of Springer Nature 2025.

关键词： Miocene

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Computational load balancing methods for algorithms parallel implementations on shared memory 20

Computational load balancing methods for algorithms parallel...

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20th Conference Scientific Services and Internet, SSI 2018

作者： Baranova, T.P. Bugerya, A.B. Gladkova, E.N. Efimkin, K.N. Solovev, M.A. Keldysh Institute of Applied Mathematics Russian Academy of Sciences Russia Ivannikov Institute for System Programming Russian Academy of Sciences Russia

The work is dedicated to the topic of various (both static and dynamic) methods of balancing the computational load with parallel implementation of algorithms on shared memory. Attention is also paid to the topic of parallelizing programs in especially difficult cases - when the used algorithm is purely sequential, there are no parallel alternatives to the algorithm used, and the execution time is unacceptably high. Various parallelization methods for software implementations of such algorithms and resulting computational load balancing are considered, allowing to obtain significant performance acceleration for application programs using purely sequential algorithms. The proposed methods of parallelizing implementations of such algorithms and balancing the resulting computational load on shared memory can help to develop efficient parallel program that fully utilize the hardware capabilities of modern computing systems with shared memory. © 2018 CEUR-WS. All rights reserved.

关键词： Parallel programming

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A Software Package for Flows Simulation in the Coastal Regions of the Kara and Barents Seas Using Shallow Water Approximation

A Software Package for Flows Simulation in the Coastal Regio...

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2021 Ivannikov Ispras Open Conference, ISPRAS 2021

作者： Ivanov, Aleksandr Keldysh Institute Of Applied Mathematics Of The Russian Academy Of Sciences Ivannikov Institute For System Programming Of The Russian Academy Of Sciences Moscow Russia

ISBN: (纸本)9781665423304

The paper describes a software package developed for modeling coastal areas of the Kara and Barents Seas using shallow water approximation. The package consists of modules that use data from open-source computational packages and the core - the module for hydrodynamic modeling. The module is based on the regularized shallow water equations system and includes wind stress, bottom friction, and tides simulation. The modeling results for the regions of the Kara Sea, Teriber Bay, Gulf of Ob, and Pechora Bay are presented. © 2021 IEEE.

关键词： Gas dynamics

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