检索结果-内蒙古大学图书馆

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

来源：评论

学校读者我要写书评

暂无评论

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

引用

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

来源：评论

学校读者我要写书评

暂无评论

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

引用

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

来源：评论

学校读者我要写书评

暂无评论

On the Dijkstra's algorithm in the pedestrian flow problem

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

引用

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

来源：评论

学校读者我要写书评

暂无评论

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

引用

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

来源：评论

学校读者我要写书评

暂无评论

Managing pharmaceuticals delivery service using a hybrid particle swarm intelligence approach

引用

ANNALs OF OPERATIONs REsEARCH 2022年第1-2期308卷 653-684页

作者： Wu, Xiaodan Li, Ruichang Chu, Chao-Hsien Amoasi, Richard Liu, shan Hebei Univ Technol Sch Econ & Management Tianjin 300401 Peoples R China Singapore Management Univ Singapore 178902 Singapore

Medicines or drugs have unique characteristics of short life cycle, small size, light weight, restrictive distribution time and the need of temperature and humidity control (selected items only). Thus, logistics companies often use different types of vehicles with different carrying capacities, and considering fixed and variable costs in service delivery, which make the vehicle assignment and route optimization more complicated. In this study, we formulate the problem to a multi-type vehicle assignment and mixed integer programming route optimization model with fixed fleet size under the constraints of distribution time and carrying capacity. Given non-deterministic polynomial hard and optimal algorithm can only be used to solve small-size problem, a hybrid particle swarm intelligence (PsI) heuristic approach, which adopts the crossover and mutation operators from genetic algorithm and 2-opt local search strategy, is proposed to solve the problem. We also adapt a principle based on cost network and Dijkstra's algorithm for vehicle scheduling to balance the distribution time limit and the high loading rate. We verify the relative performance of the proposed method against several known optimal or heuristic solutions using a standard data set for heterogeneous fleet vehicle routing problem. Additionally, we compare the relative performance of our proposed Hybrid PsI algorithm with two intelligent-based algorithms, Hybrid Population Heuristic algorithm and Improved Genetic algorithm, using a real-world data set to illustrate the practical and validity of the model and algorithm.

关键词： Medical logistics Pharmaceuticals delivery Vehicle routing problem Hybrid particle swarm intelligence algorithm Dijkstra’ s algorithm

来源：评论

学校读者我要写书评

暂无评论

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

引用

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

来源：评论

学校读者我要写书评

暂无评论

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

引用

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

来源：评论

学校读者我要写书评

暂无评论

Certified Quantum Computation in Isabelle/HOL

引用

JOURNAL OF AUTOMATED REAsONING 2021年第5期65卷 691-709页

作者： Bordg, Anthony Lachnitt, Hanna He, Yijun Univ Cambridge Dept Comp Sci & Technol Cambridge England Stanford Univ Dept Comp Sci Stanford CA 94305 USA Univ Cambridge Cambridge England

In this article we present an ongoing effort to formalise quantum algorithms and results in quantum information theory using the proof assistant Isabelle/HOL. Formal methods being critical for the safety and security of algorithms and protocols, we foresee their widespread use for quantum computing in the future. We have developed a large library for quantum computing in Isabelle based on a matrix representation for quantum circuits, successfully formalising the no-cloning theorem, quantum teleportation, Deutsch's algorithm, the Deutsch-Jozsa algorithm and the quantum Prisoner's Dilemma. We discuss the design choices made and report on an outcome of our work in the field of quantum game theory.

关键词： Isabelle HOL Certification Quantum computing No-cloning Quantum teleportation Deutsch’ s algorithm Deutsch– Jozsa algorithm Quantum prisoner’ s dilemma

来源：评论

学校读者我要写书评

暂无评论

simultaneous Reconfiguration and Optimal Capacitor Placement Using Adaptive Whale Optimization algorithm for Radial Distribution system

引用

JOURNAL OF ELECTRICAL ENGINEERING & TECHNOLOGY 2021年第1期16卷 181-190页

作者： Babu, M. Ramesh Kumar, C. Venkatesh Anitha, s. St Josephs Coll Engn Dept Elect & Elect Engn OMR Chennai 600119 Tamil Nadu India IFET Coll Engn Dept Elect & Elect Engn Viluppuram 605602 Tamil Nadu India

The losses in the distribution networks due to the line resistance decrease the overall efficiency of the power distribution. Reducing the power losses and regulating the voltages within the limits are necessary to provide quality power to the consumers. The power loss can be minimized by optimum network reconfiguration and the placement of the capacitors. Considering independent network reconfiguration and placement of the capacitor is not effective during heavy loading conditions. This paper proposes a simultaneous network reconfiguration and capacitor placement in radial distribution network to minimize the real power losses, operating cost and to improve the bus voltages. The Johnson's algorithm is used to find the minimal spanning tree during the network reconfiguration and an adaptive whale optimization algorithm is used as an optimization method. The proposed methodology is tested on standard IEEE 33-bus and 69-bus radial distribution systems. The effectiveness of the proposed method is validated by comparing the results with previous result reported in the literature in terms of cost saving and loss reduction.

关键词： Adaptive whale algorithm Network reconfiguration Johnson’ s algorithm Optimal capacitor placement Power loss reduction Operating cost minimization

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：