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Breaking tweakable enciphering schemes using simon's algorithm

DEsIGNs CODEs AND CRYPTOGRAPHY 2021年第8期89卷 1907-1926页

作者： Ghosh, sebati sarkar, Palash Indian Stat Inst 203 BT Rd Kolkata 700108 India

We show the applicability of simon's period finding quantum algorithm to the cryptanalysis of several tweakable enciphering schemes (TEss), namely, CMC, EME, XCB, TET and FAsT. For all of the five TEss, we show di... 详细信息

关键词： Tweakable enciphering scheme simon’ s algorithm

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On the Dijkstra's algorithm in the pedestrian flow problem

On the Dijkstra's algorithm in the pedestrian flow prob...

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作者： Petrášová, Tereza Charles University of Prague

Title: On the Dijkstra's algorithm in the Pedestrian Flow Problem Author: Tereza Petrášová Department: Department of Numerical Mathematics supervisor: doc. RNDr. Jiří Felcman, Csc., Department of Numerical Mathe- matics Abstract: The pedestrian flow problem is described by a coupled system of the first order hyperbolic partial differential equations with the source term and by the functional minimization problem for the desired direction of motion. The functional minimization is based on the modified Dijkstra's algorithm used to find the minimal path to the exit. The original modification of the Dijkstra's algorithm is proposed to increase its efficiency in the pedestrian flow problem. This approach is compared with the algorithm of Bornemann and Rasch for determination of the desired direction of motion based on the solution of the so- called Eikonal equation. Both approaches are numerically tested in the framework of two splitting algorithms for solution of the coupled problem. The former splitting algorithm is based on the finite volume method yielding for the given time instant the piecewise constant approximation of the solution. The latter one uses the implicit discretization by a space-time discontinuous Galerkin method based on the discontinuous piecewise polynomial approximation. The numerical examples...

关键词： hyperbolic systém pedestrian flow equations Eikonal equation Dijkstra&apos s algorithm

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Weight Calculation Alternative Methods in Prime's algorithm Dedicated for Power system Restoration strategies

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ENERGIEs 2020年第22期13卷 6063-6063页

作者： Lukaszewski, Artur Nogal, Lukasz Robak, sylwester Warsaw Univ Technol Elect Power Engn Inst Koszykowa St 75 PL-00662 Warsaw Poland

In self-healing grid systems, high utility in the use of greedy algorithms is observed. One of the most popular solutions is based on Prim's algorithm. In the computation, the power grid is represented as a weighted graph. This paper presents a few possibilities of calculation of the numerical weight of a branch of the graph. The proposition of a modified edge weight calculation based on active power belongs to this group. The other solutions are novel subalgorithms bounded by real power, reactive power, and normalized factor. This factor is a mathematical combination of active and reactive power multiplied by influence coefficients. Requirements necessary for a power system are applied in the considered algorithms. Each of these proposed algorithms includes the power source limits, voltage level at busbars, and power system transmission features, such as transmission lines rated currents and power losses. All mentioned methods were compiled into separate algorithms, which can be used to compute graph model parameters. A simulation model based on Prim's algorithm was prepared to compare the suitability of presented concepts. All weights of the subalgorithms were compared to each other. That is why different power system restoration strategies may require various methods of calculating weights of the graph's branches.

关键词： spanning tree greedy algorithms graph theory Prim’ s algorithm restoration strategy

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An Automatic Concrete Crack-Detection Method Fusing Point Clouds and Images Based on Improved Otsu's algorithm

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sENsORs 2021年第5期21卷 1581-1581页

作者： Chen, Xiaolong Li, Jian Huang, shuowen Cui, Hao Liu, Peirong sun, Quan Zhengzhou Univ Sch Water Conservancy Sci & Engn Zhengzhou 450001 Peoples R China Zhengzhou Univ Sch Geosci & Technol Zhengzhou 450001 Peoples R China

Cracks are one of the main distresses that occur on concrete surfaces. Traditional methods for detecting cracks based on two-dimensional (2D) images can be hampered by stains, shadows, and other artifacts, while various three-dimensional (3D) crack-detection techniques, using point clouds, are less affected in this regard but are limited by the measurement accuracy of the 3D laser scanner. In this study, we propose an automatic crack-detection method that fuses 3D point clouds and 2D images based on an improved Otsu algorithm, which consists of the following four major procedures. First, a high-precision registration of a depth image projected from 3D point clouds and 2D images is performed. second, pixel-level image fusion is performed, which fuses the depth and gray information. Third, a rough crack image is obtained from the fusion image using the improved Otsu method. Finally, the connected domain labeling and morphological methods are used to finely extract the cracks. Experimentally, the proposed method was tested at multiple scales and with various types of concrete crack. The results demonstrate that the proposed method can achieve an average precision of 89.0%, recall of 84.8%, and F1 score of 86.7%, performing significantly better than the single image (average F1 score of 67.6%) and single point cloud (average F1 score of 76.0%) methods. Accordingly, the proposed method has high detection accuracy and universality, indicating its wide potential application as an automatic method for concrete-crack detection.

关键词： concrete crack detection the fusion of point clouds and images 3D laser point cloud Otsu’ s algorithm

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An engineering interpretation of Nesterov's convex minimization algorithm and time integration: application to optimal fiber orientation

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COMPUTATIONAL MECHANICs 2021年第1期68卷 211-227页

作者： Areias, P. Rabczuk, T. Univ Lisbon DEM Mech Engn Dept Inst Super Tecn Ave Rovisco Pais P-1049001 Lisbon Portugal IDMEC Lisbon Portugal Bauhaus Univ Weimar Inst Struct Mech Marienstr 15 D-99423 Weimar Germany

Nesterov's 1983 first-order minimization algorithm is equivalent to the numerical solution of a second-order ODE with non-constant damping. It is known that the algorithm can be obtained by time discretization with asynchronous damping, a long-standing technique in computational explicit dynamics. We extend the solution of the ODE to other time discretization algorithms, analyze their properties and provide an engineering interpretation of the process as well as a prototype implementation, addressing the estimation of the relevant parameters in the computational mechanics context. The main result is that a standard Newmark-type time-integration finite element code can be adopted to perform classical optimization in mechanics. standard FE analysis, sensitivity analysis and optimization are performed in sequence using a typical FE framework. Geometric nonlinearities in the conservative case are addressed by the adjoint-variable method and examples of optimal fiber orientation are shown, exhibiting remarkable advantages with respect to more traditional optimization algorithms.

关键词： First-order optimization Nesterov’ s algorithm Time-integration Optimal fiber orientation Geometrically nonlinear

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single-Pulse simultaneous Target Detection and Angle Estimation in a Multichannel Phased Array Radar

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IEEE TRANsACTIONs ON sIGNAL PROCEssING 2020年 68卷 6649-6664页

作者： Aubry, Augusto Maio, Antonio De Marano, stefano Rosamilia, Massimo Univ Naples Federico II DIETI Via Claudio 21 I-80125 Naples Italy Univ Salerno Dipartimento Ingn Informaz Elettr & Matemat Appl I-84084 Fisciano Italy

This paper is focused on simultaneous target detection and angle estimation with a multichannel phased array radar. Resorting to a linearized expression for the array steering vector around the beam pointing direction, the problem is formulated as a composite binary hypothesis test where the unknowns, under the alternative hypothesis, include the target directional cosines displacements with respect to the array nominal coarse pointing direction. The problem is handled via the Generalized Likelihood Ratio (GLR) criterion (both one-step and two-step) where decision statistics leveraging the Maximum Likelihood Estimates (MLEs) of the parameters are compared with a detection threshold. If crossed, target presence is declared and the MLEs of the aforementioned displacements directly provide target angular position with respect to the pointing direction. From the analytic point of view, ML estimation involves a constrained fractional quadratic optimization problem whose optimal solution can be found via the Dinkelbach's algorithm or approximated through a fast-converging procedure based on a Coordinate Descent (CD) optimization. The performance analysis of the proposed architectures as well as the corresponding discussion is developed in terms of computational complexity, Constant False Alarm Rate (CFAR) behavior, detection performance, and angular estimation accuracy, also in comparison with some counterparts available in the open literature and theoretical benchmark limits.

关键词： Radar Object detection Optimization Interference Transmission line matrix methods Radar detection Phased arrays Adaptive radar detection dinckebach&apos s algorithm array signal processing

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smart Control of an Electric Vehicle for Ancillary service in DC Microgrid

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IEEE ACCEss 2020年 8卷 197222-197235页

作者： Yu, Yue Nduka, Onyema sunday Pal, Bikash C. Imperial Coll London Control & Power Grp London SW7 2AZ England Royal Holloway Univ London Dept Elect Engn London TW20 0EX England

This article presents a two-stage framework for optimal Electric Vehicle (EV) charging/discharging strategy for DC Microgrid (MG) with Distributed Generators (DGs). A multi-objective optimisation task aimed at minimising system losses and EV battery degradation with Vehicle-to-Grid (V2G) peak shaving service has been realised. This coordinated EV integration into the DCMG was formulated as a directed weighted single source shortest path problem that was solved using a modified Dijkstra's algorithm. The weights of the edges were obtained using primal-dual interior point method. The proposed framework has been experimentally verified using simulations with a test DCMG system with practical IEEE European low voltage test feeder load profiles. Results show realisation of peak demand shaving leveraging on EV discharge with minimal on-board battery degradation as well as reduced system losses. It is also shown that the proposed two-stage framework reduces the battery state of charge (sOC) sample space requirements in the analysis, thus, reducing the computational burden.

关键词： Batteries Optimization state of charge Vehicle-to-grid Resistance Load modeling Microgrids EV integration dc microgrid control V2G battery degradation multi-objective optimisation optimal power flow modified Dijkstra’ s algorithm power losses

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FR-RED: Fractal Residual Based Real-Time Detection of the LDos Attack

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IEEE TRANsACTIONs ON RELIABILITY 2021年第3期70卷 1143-1157页

作者： Tang, Dan Feng, Ye Zhang, siqi Qin, Zheng Hunan Univ Coll Comp Sci & Elect Engn Changsha 410082 Peoples R China

The low-rate denial of service (LDos) attack mainly exploits security vulnerabilities of adaptive mechanisms in network protocols and application services. The high-rate attack pulses within a short time interval are sent periodically, which will result in the degradation of service quality. The attack traffic is similar to normal traffic from legitimate users in the network, consequently, it is easy to escape the traditional detection methods because of its intermittence. Research works have demonstrated that there are fractal characteristics (self-similarity) of the network traffic over the large scale of time. Although the fractal characteristics of the network traffic will be changed under the LDos attack, the variations of the fractal characteristics in some network states are not apparent in real-time detection. Based on the fractal characteristics, the fractal residual of the network traffic is analyzed through the Hurst parameters calculating process by R/s algorithm in this article. It can be found that the fractal residual of the network traffic can better reflect the different states of the LDos attack. Combining the idea behind the sliding window, a novel fractal residual based real-time detection (FR-RED) method of the LDos attack is proposed. The effectiveness of the method in this article is verified by performing some experiments on two platforms, the Ns2 and test-bed. The results manifest the beginning and end of the LDos attack can be estimated in real-time with high detection accuracy.

关键词： Fractals Real-time systems Protocols Wireless sensor networks Computer crime Microsoft Windows signal processing algorithms Fractal characteristics fractal residual low-rate denial of service (LDos) attack R s algorithm real-time detection sliding window

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Identification of Logic Paths Influenced by severe Coupling Capacitances

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JOURNAL OF ELECTRONIC TEsTING-THEORY AND APPLICATIONs 2020年第6期36卷 731-741页

作者： Meza-Ibarra, I. D. Champac, V Gomez-Fuentes, R. Noriega, J. R. Vera-Marquina, A. Univ Sonora Dept Invest Fis Hermosillo Sonora Mexico Natl Inst Astrophys Opt & Elect Puebla Mexico

signals in modern integrated circuits travel through complex interconnect structures, which present several layers and important coupling capacitance effects. Even more, the impact of signal coupling on the overall circuit behavior has grown with technology scaling as the interconnect have become taller. In this paper, a methodology to identify those logic paths more significantly influenced by the coupling capacitances is presented. The proposed methodology is based on a modified Dijkstra's algorithm, which finds those paths between a primary input and a primary output more severely influenced by the coupling capacitances. This methodology can be used to validate circuit behavior and it can also be applied in testing techniques oriented to detect interconnect defects (e.g., opens and short defects). The proposed methodology is applied to IsCAs'85 benchmark circuits to show its feasibility.

关键词： Dijkstra’ s algorithm Coupling capacitances Logic paths IsCAs’ 85 circuits Interconnection lines

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Evaluation of Mechanical Properties of Composite solid Propellant by Genetic Engineering of Materials: Part B: Modeling of Minimum Representative Unit for Multi-Modal Particle Packing structure Based on Formulation of Composite solid Propellant

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PROPELLANTs EXPLOsIVEs PYROTECHNICs 2021年第4期46卷 654-662页

作者： Dong, Ge Zhang, Wei Zhou, Xing Bao, Tong Deng, Lei Natl Univ Def Technol Coll Aerosp Sci & Technol Deya Rd Changsha 410073 Peoples R China

To show the actual particle packing structure of AP/Al/HTPB propellant with multi-modal fillers, a minimum representative unit of particle packing structure is established. In the minimum representative unit, the particle size of fillers in each mode is identical to the value in the propellant formulation. Meanwhile, on the basis of the amount series of fillers in the per unit propellant, the amount of fillers in each mode is respectively divided by that of the fewest filler, thus the amount series of fillers in the minimum representative unit is obtained. Further, with the condition that the average density of the unit is the same as that of the propellant, the side length of the minimum representative unit could be uniquely determined. In order to generate the particle packing structure with particles evenly distributed in the unit, a two-step algorithm is put forward. In the first step, the genetic algorithm is adopted to search for an evenly and non-overlapping distribution for the few and coarser particles. In the second step, the residual finer particles are randomly placed in the voids among the coarser particles by a modified L-s algorithm. Results showed that the particles are distributed more evenly in the packs generated by the two-step algorithm than in packs generated by the classic L-s algorithm.

关键词： Particle packing structure Minimum representative unit Multi-modal particles L− s algorithm Genetic algorithm

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