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Ivannikov Ispras Open Conference (ISPRAS)

作者： Wang, Tianyuan Shi, Hongda Zhang, Qin Yang, Bo Liu, Xin Matvey, Kraposhin Ocean Univ China Coll Engn Qingdao Peoples R China RAS Ivannikov Inst Syst Programming Moscow Russia

ISBN: (纸本)9781665412919

The paper attempts to apply the Proper Orthogonal Decomposition (POD) and Dynamic Mode Decomposition (DMD) to the ducted propeller wake analysis. The ducted propeller produces a complex wake flow field with multifrequency vortex structure coupling under the influence between blades and nozzle. Traditional analysis methods such as time-averaged flow, phase-averaged flow are only displaying the coupling results. In contrast, data mining technologies such as POD and DMD can extract independent flow patterns from the massive data obtained from physical experiments and numerical simulations. The paper focuses on the influence of computational subdomain (based on the OpenFOAM), snapshot sampling interval and data coverage revolutions on the modal convergence in the data preprocessing before employing POD and DMD. Taking a single ducted propeller wake data with the advance coefficient of J=0.4 as an example, it is found that the sampling interval of snapshots are independent of modal convergence after reaching a certain level and only affect the frequency range of the captured modes. The scope of the computational subdomain and the revolutions of data covered by snapshot matrix are vital factors to affect the modal convergence. At last, under the premise of modal convergence, the paper reconstructs the ducted propeller wake flow field by POD and DMD respectively, where errors between the original data can be ignored.

关键词： POD DMD the ducted propeller wake the OpenFOAM

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Algorithm for Constructing Modular Projections for Correcting Multiple Errors Based on a Redundant Residue Number system Using Maximum Likelihood Decoding

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programming AND COMPUTER SOFTWARE 2021年第8期47卷 839-848页

作者： Babenko, M. Nazarov, A. Tchernykh, A. Pulido-Gaytan, B. Cortes-Mendoza, J. M. Vashchenko, I North Caucasus Fed Univ North Caucasus Ctr Math Res Stavropol 355029 Russia Russian Acad Sci Inst Syst Programming Moscow 109004 Russia Sirius Univ Sci & Technol Soci 354340 Russia CICESE Res Ctr Ensenada 22860 Baja California Mexico South Ural State Univ Chelyabinsk Russia

One of the most important applications of the Redundant Residual Numbers system (RRNS) is to improve the fault tolerance of the data storage, processing, and transmission. Correcting multiple errors is a challenging computational task. This complexity is mainly due to the numerous combinations of erroneous residuals at the error localization stage. In this paper, we propose an approach for constructing modular projections to correct any number of errors. The algorithm uses the Maximum Likelihood Decoding (MLD) and the Approximate Rank (AR) to reduce the number of projections and processing time. AR-RRNS with MLD algorithm can provide the number of modular projections close to the theoretical lower bound of the most efficient state-of-the-art algorithm.

关键词： Computer Science general Software Engineering/programming and Operating systems Operating systems Software Engineering Artificial Intelligence

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A Model and Method for Detecting Information Campaigns

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programming AND COMPUTER SOFTWARE 2021年第4期47卷 261-270页

作者： Turdakov, D. Yu. Garbuk, S. V. Khenkin, P. V. Kozlov, I. S. Laguta, A. V. Varlamov, M. I. Russian Acad Sci Ivannikov Inst Syst Programming Ul Solzhenitsyna 25 Moscow 109004 Russia Moscow MV Lomonosov State Univ Moscow 119991 Russia Natl Res Univ Higher Sch Econ Ul Myasnitskaya 20 Moscow 101000 Russia Adv Res Fdn Berezhkovskaya Nab 22 3 Moscow 121059 Russia

This paper investigates the possibility of automatic detection of information campaigns in the absence of a priori knowledge about the fact of their running, their goals, affected objects, and target audience. We propose a general model of information campaigns and also highlight some features of hidden information campaigns. The model is suitable for describing information campaigns both in social media and in traditional media, including those outside of the Internet. A method for detecting information campaigns, which allows the problem to be solved in automatic mode, is proposed. To confirm the efficiency of the method, an experimental study was carried out on data collected from social media. We invited some experts in related fields to label text messages and create a test corpus. To analyze the complexity of the problem, we measured the degree of cross-expert agreement. Results of the analysis confirmed the initial hypothesis that, even for professionals, the detection of hidden information campaigns is not a trivial task. Nevertheless, using the voting method, we built a test collection to study particular information campaign features, as well as compared the proposed method with individual answers provided by the experts. Result of the experiments confirmed a high potential of the proposed approach to the problem of automatic detection of information campaigns.

关键词： Computer Science general Software Engineering/programming and Operating systems Operating systems Software Engineering Artificial Intelligence

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Airport terminal building capacity evaluation using queuing system

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ALEXANDRIA ENGINEERING JOURNAL 2022年第12期61卷 10109-10118页

作者： Alnowibet, Khalid Abdulaziz Khireldin, Awad Abdelawwad, Mohamed Mohamed, Ali Wagdy King Saud Univ Coll Sci Stat & Operat Res Dept POB 2455 Riyadh 11451 Saudi Arabia Air Transport Management ATM SIT RP Bldg Woodlands43 Woodlands Ave 9 Singapore Singapore Univ Kassel Inst Comp Architecture & Syst Programming Kassel Germany Cairo Univ Fac Grad Studies Stat Res Operat Res Dept Giza 12613 Egypt Amer Univ Cairo Sch Sci Engn Dept Math & Actuarial Sci Cairo Egypt

Queues or waiting lines are a natural occurrence in the everyday lives of consumers and the process of every business. Being customers' first point of contact with the business, a customer's experience in the queue becomes a determining factor of their first impression of the business. Queuing provides the cornerstone of efficiency to businesses as they assist employees and managers in tracking, prioritising, and ensuring the delivery of services and transactions. Inefficiencies in queues are undesired as they can result in substantial losses to a business, such as bad reputation and loss of customers due to balking or reneging *** research has shown that the application of queuing theory enables businesses to analyse their queuing system and the trends of demand for their services. This allows the business to effectively identify measures to improve their queuing system and serve demand at the desired level of *** this paper, where it examined Cairo International Airport (CAI)'s existing departure queue system and benchmarked it against the optimum wait time suggested in the International Air Transport Association's (IATA) Level of Service (LoS) concept. The application of Kendall-Lee's Notation is applied to describe the existing queuing system of the airport. It also suggested areas of improvement after the analysis and recommended that the CAI focus on improving service time for its Check-in, Security, and Boarding process. Although the Immigration process has met IATA's recommended optimal wait time, training could be provided to employees to enable them to progressively work towards a better service time and prepare for the future higher traffic *** team has also suggested for CAI to introduce autonomous technology for the departure process and software which analyses passenger flow and projects a forecast value based on the airport growth trends.(c) 2022 THE AUTHORS. Published by Elsevier BV on behalf of Faculty of Engineering, Al

关键词： Airport Capacity IATA Level of service Queuing theory Terminal building

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Lower Bounds and Optimal Algorithms for Smooth and Strongly Convex Decentralized Optimization Over Time-Varying Networks 35

Lower Bounds and Optimal Algorithms for Smooth and Strongly ...

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35th Conference on Neural Information Processing systems (NeurIPS)

作者： Kovalev, Dmitry Gasanov, Elnur Gasnikov, Alexander Richtarik, Peter King Abdullah Univ Sci & Technol Thuwal Saudi Arabia MIPT Moscow Russia ISP RAS Moscow Russia Moscow Inst Phys & Technol Moscow Russia Russian Acad Sci Res Ctr Trusted Artificial Intelligence Inst Syst Programming Moscow Russia

ISBN: (纸本)9781713845393

We consider the task of minimizing the sum of smooth and strongly convex functions stored in a decentralized manner across the nodes of a communication network whose links are allowed to change in time. We solve two fundamental problems for this task. First, we establish the first lower bounds on the number of decentralized communication rounds and the number of local computations required to find an.-accurate solution. Second, we design two optimal algorithms that attain these lower bounds: (i) a variant of the recently proposed algorithm ADOM (Kovalev et al., 2021) enhanced via a multi-consensus subroutine, which is optimal in the case when access to the dual gradients is assumed, and (ii) a novel algorithm, called ADOM+, which is optimal in the case when access to the primal gradients is assumed. We corroborate the theoretical efficiency of these algorithms by performing an experimental comparison with existing state-of-the-art methods.

关键词： Time varying networks

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Automated Generation of Machine instruction Decoders

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programming AND COMPUTER SOFTWARE 2019年第7期45卷 390-397页

作者： Fokina, N. Yu Solovev, M. A. Russian Acad Sci Ivannikov Inst Syst Programming Moscow 109004 Russia

A method for the automated generation of machine instruction decoders for a wide range of processor architectures that uses the target architecture assembler is proposed. A software tool based on this method is implem... 详细信息

关键词： Decoding

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RRNS Base Extension Error-Correcting Code for Performance Optimization of Scalable Reliable Distributed Cloud Data Storage

RRNS Base Extension Error-Correcting Code for Performance Op...

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35th IEEE International Parallel and Distributed Processing Symposium (IPDPS)

作者： Babenko, Mikhail Tchernykh, Andrei Pulido-Gaytan, Bernardo Cortes-Mendoza, Jorge M. Shiryaev, Egor Golimblevskaia, Elena Avetisyan, Arutyun Nesmachnow, Sergio North Caucasus Fed Univ Stavropol Russia CICESE Res Ctr Ensenada Baja California Mexico South Ural State Univ Chelyabinsk Russia RAS Ivannikov Inst Syst Programming Moscow Russia Univ Republica Montevideo Uruguay

ISBN: (纸本)9781665435772

Ensuring reliable data storage in a cloud environment is a challenging problem. One of the efficient mechanisms used to solve it is the Redundant Residue Number system (RRNS) with the projection method, a commonly used mechanism for detecting errors. However, the error correction based on the projection method has exponential complexity depending on the number of control and working moduli. In this paper, we propose an optimization mechanism using a base extension and Hamming distance to reduce the number of calculated projections. We show that they can be reduced up to three times than the classical projection method and, hence, the time complexity of data recovery in the distributed cloud data storage.

关键词： cloud computing residue number system reliability error-correcting code uncertainty

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On the Calculation of the Vortex Sheet and Point Vortices Effects at Approximate Solution of the Boundary Integral Equation in 2D Vortex Methods of Computational Hydrodynamics

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FLUID DYNAMICS 2019年第7期54卷 991-1001页

作者： Kuzmina, K. S. Marchevskii, I. K. Bauman Moscow State Syst Univ Moscow Russia RAS Ivannikov Inst Syst Programming Moscow Russia

When simulating incompressible flow around airfoil using vortex methods of computational hydrodynamics, it is necessary to solve the boundary integral equation with respect to the intensity of the vortex sheet at the airfoil surface line. For its approximate solution, the Galerkin method with a piecewise-constant and piecewise-linear representation of the solution on the airfoil surface line can be applied. The coefficients of the system of linear equations, arising from the procedure of discretization of the integral equation, e xpress the influence of the vortex sheet located on the panels of the airfoil surface line on other panels;the components of the right-hand side vector express the influence of point vortices that simulate a vortex wake in the flow domain. For the case of the airfoil surface line approximation with a polyline consisting of rectilinear panels, exact analytical expressions are obtained for the coefficients of the matrix and the right-hand side vector;for the case of taking into account the curvature of the panels, an approach for their approximate calculation is proposed and all the necessary formulae are derived.

关键词： vortex methods boundary integral equation computational hydrodynamics

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SmmPack: Obfuscation for SMM Modules with TPM Sealed Key 21st

SmmPack: Obfuscation for SMM Modules with TPM Sealed Key

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21st Conference on Detection of Intrusions and Malware and Vulnerability Assessment (DIMVA)

作者： Matsuo, Kazuki Tanda, Satoshi Suzaki, Kuniyasu Kawakoya, Yuhei Mori, Tatsuya Waseda Univ 3-4-1 OkuboShinjuku Tokyo 1698555 Japan Inst Informat Secur 2-14-1 TsuruyachoKanagawa Ku Yokohama Kanagawa 2210835 Japan NTT Secur Japan KK 4-14-1 SotokandaChiyoda Ku Tokyo 1010021 Japan Satoshis Syst Programming Lab Vancouver BC Canada NICT 4-2-1 Nuki Kitamachi Kokubunji Tokyo 1840015 Japan RIKEN AIP 15th FloorNihonbashi 1-4-1Chuo Ku Tokyo 1030027 Japan

ISBN: (纸本)9783031641701;9783031641718

system Management Mode (SMM) is the highest-privileged operating mode of x86 and x86-64 processors. Through SMM exploitation, attackers can tamper with the Unified Extensible Firmware Interface (UEFI) firmware, disabling the security mechanisms implemented by the operating system and hypervisor. Vulnerabilities enabling SMM code execution are often reported as Common Vulnerabilities and Exposures (CVEs);however, no security mechanisms currently exist to prevent attackers from analyzing those vulnerabilities. To increase the cost of vulnerability analysis of SMM modules, we introduced SmmPack. The core concept of SmmPack involves encrypting an SMM module with the key securely stored in a Trusted Platform Module (TPM). We assessed the effectiveness of SmmPack in preventing attackers from obtaining and analyzing SMM modules using various acquisition methods. Our results show that SmmPack significantly increases the cost by narrowing down the means of module acquisition. Furthermore, we demonstrated that SmmPack operates without compromising the performance of the original SMM modules. We also clarified the management and adoption methods of SmmPack, as well as the procedure for applying BIOS updates, and demonstrated that the implementation of SmmPack is realistic.

关键词： UEFI SMM TPM2.0 Packing

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Sydr: Cutting Edge Dynamic Symbolic Execution

Sydr: Cutting Edge Dynamic Symbolic Execution

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Ivannikov Ispras Open Conference (ISPRAS)

作者： Vishnyakov, Alexey Fedotov, Andrey Kuts, Daniil Novikov, Alexander Parygina, Darya Kobrin, Eli Logunova, Vlada Belecky, Pavel Kurmangaleev, Shamil RAS Ivannikov Inst Syst Programming Moscow Russia Lomonosov Moscow State Univ Moscow Russia Moscow Inst Phys & Technol Moscow Russia

ISBN: (纸本)9781665412919

The security development lifecycle (SDL) is becoming an industry standard. Dynamic symbolic execution (DSE) has enormous amount of applications in computer security (fuzzing, vulnerability discovery, reverse-engineering, etc.). We propose several performance and accuracy improvements for dynamic symbolic execution. Skipping non-symbolic instructions allows to build a path predicate 1.2-3.5 times faster. Symbolic engine simplifies formulas during symbolic execution. Path predicate slicing eliminates irrelevant conjuncts from solver queries. We handle each jump table (switch statement) as multiple branches and describe the method for symbolic execution of multi-threaded programs. The proposed solutions were implemented in Sydr tool. Sydr performs inversion of branches in path predicate. Sydr combines DynamoRlO dynamic binary instrumentation tool with Triton symbolic engine. We evaluated Sydr features on 64-bit Linux executables.

关键词： symbolic execution concolic execution dynamic analysis binary analysis dynamic binary instrumentation computer security security development lifecycle DSE SMT DBI SDL

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