• Title/Summary/Keyword: Binary search algorithm

Search Result 154, Processing Time 0.026 seconds

Optimum parameterization in grillage design under a worst point load

  • Kim Yun-Young;Ko Jae-Yang
    • Journal of Navigation and Port Research
    • /
    • v.30 no.2
    • /
    • pp.137-143
    • /
    • 2006
  • The optimum grillage design belongs to nonlinear constrained optimization problem. The determination of beam scantlings for the grillage structure is a very crucial matter out of whole structural design process. The performance of optimization methods, based on penalty functions, is highly problem-dependent and many methods require additional tuning of some variables. This additional tuning is the influences of penalty coefficient, which depend strongly on the degree of constraint violation. Moreover, Binary-coded Genetic Algorithm (BGA) meets certain difficulties when dealing with continuous and/or discrete search spaces with large dimensions. With the above reasons, Real-coded Micro-Genetic Algorithm ($R{\mu}GA$) is proposed to find the optimum beam scantlings of the grillage structure without handling any of penalty functions. $R{\mu}GA$ can help in avoiding the premature convergence and search for global solution-spaces, because of its wide spread applicability, global perspective and inherent parallelism. Direct stiffness method is used as a numerical tool for the grillage analysis. In optimization study to find minimum weight, sensitivity study is carried out with varying beam configurations. From the simulation results, it has been concluded that the proposed $R{\mu}GA$ is an effective optimization tool for solving continuous and/or discrete nonlinear real-world optimization problems.

Development of High Speed Scalar Product Operation System for ECC Public Key (타원곡선 공개키 생성을 위한 고속 스칼라곱 연산 시스템 구현)

  • Kim, Kap-Yol;Lee, Chul-Soo;Park, Seok-Cheon
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.14 no.2
    • /
    • pp.394-402
    • /
    • 2010
  • At a recent, enterprises based on online-service are established because of rapid growth of information network. These enterprises collect personal information and do customer management. If customers use a paid service, company send billing information to customer and customer pay it. Such circulation and management of information is big issue but most companies don't care of information security. Actually, personal information that was managed by largest internal open-market was exposed. For safe customer information management, this paper proposes the method that decrease load of RSA cryptography algorithm that is commonly used for preventing from illegal attack or hacking. The method for decreasing load was designed by Binary NAF Method and it can operates modular Exponentiation rapidly. We implemented modular Exponentiation algorithm using existing Binary Method and Windows Method and compared and evaluated it.

An Efficient Algorithm for the Generalized Continuous Multiple Choice linear Knapsack Problem (일반연속 다중선택 선형배낭문제의 효율적인 해법연구)

  • Won, Joong-Yeon
    • Journal of Korean Institute of Industrial Engineers
    • /
    • v.23 no.4
    • /
    • pp.661-667
    • /
    • 1997
  • We consider a generalized problem of the continuous multiple choice knapsack problem and study on the LP relaxation of the candidate problems which are generated in the branch and bound algorithm for solving the generalized problem. The LP relaxed candidate problem is called the generalized continuous multiple choice linear knapsack problem and characterized by some variables which are partitioned into continuous multiple choice constraints and the others which only belong to simple upper bound constraints. An efficient algorithm of order O($n^2logn$) is developed by exploiting some structural properties and applying binary search to ordered solution sets, where n is the total number of variables. A numerical example is presented.

  • PDF

A New Calibration Algorithm of a Five-Hole Pressure Probe for Flow Velocity Measurement (유동속도계측을 위한 5공압력프로브의 새로운 교정 알고리듬)

  • Kim, J.K.;Oh, S.H.
    • Journal of Power System Engineering
    • /
    • v.12 no.4
    • /
    • pp.18-25
    • /
    • 2008
  • This paper investigated the new calibration algorithm of a straight-type five-hole pressure probe necessary for calculating three-dimensional flow velocity components. The new data reduction method Includes a look-up, a geometry transformation such as the translation and reflection of nodes, and a binary search algorithm. This new calibration map was applied up to the application angle, ${\pm}55^{\circ}$ of a probe. As a result, this data reduction method showed a perfect performance without any kind of interpolation errors In calculating yaw and pitch angle from the calibration map.

  • PDF

Modifiable Walking Pattern Generation Handling Infeasible Navigational Commands for Humanoid Robots

  • Lee, Bum-Joo;Kim, Kab Il
    • Journal of Electrical Engineering and Technology
    • /
    • v.9 no.1
    • /
    • pp.344-351
    • /
    • 2014
  • In order to accomplish complex navigational commands, humanoid robot should be able to modify its walking period, step length and direction independently. In this paper, a novel walking pattern generation algorithm is proposed to satisfy these requirements. Modification of the walking pattern can be considered as a transition between two periodic walking patterns, which follows each navigational command. By assuming the robot as a linear inverted pendulum, the equations of motion between ZMP(Zero Moment Point) and CM(Center of Mass) state is easily derived and analyzed. After navigational command is translated into the desired CM state, corresponding CM motion is generated to achieve the desired state by using simple ZMP functions. Moreover, when the command is not feasible, feasible command is alternated by using binary search algorithm. Subsequently, corresponding CM motion is generated. The effectiveness of the proposed algorithm is verified by computer simulation.

A New Design of Signal Constellation of the Spiral Quadrature Amplitude Modulation (나선 직교진폭변조 신호성상도의 새로운 설계)

  • Li, Shuang;Kang, Seog Geun
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.24 no.3
    • /
    • pp.398-404
    • /
    • 2020
  • In this paper, we propose a new design method of signal constellation of the spiral quadrature amplitude modulation (QAM) exploiting a modified gradient descent search algorithm and its binary mapping rule. Unlike the conventional method, the new method, which uses and the constellation optimization algorithm and the maximum number of iterations as a parameter for the iterative design, is more robust to phase noise. And the proposed binary mapping rule significantly reduces the average Hamming distance of the spiral constellation. As a result, the proposed spiral QAM constellation has much improved error performance compared to the conventional ones even in a very severe phase noise environment. It is, therefore, considered that the proposed QAM may be a useful modulation format for coherent optical communication systems and orthogonal frequency division multiplexing (OFDM) systems.

Robustness, Data Analysis, and Statistical Modeling: The First 50 Years and Beyond

  • Barrios, Erniel B.
    • Communications for Statistical Applications and Methods
    • /
    • v.22 no.6
    • /
    • pp.543-556
    • /
    • 2015
  • We present a survey of contributions that defined the nature and extent of robust statistics for the last 50 years. From the pioneering work of Tukey, Huber, and Hampel that focused on robust location parameter estimation, we presented various generalizations of these estimation procedures that cover a wide variety of models and data analysis methods. Among these extensions, we present linear models, clustered and dependent observations, times series data, binary and discrete data, models for spatial data, nonparametric methods, and forward search methods for outliers. We also present the current interest in robust statistics and conclude with suggestions on the possible future direction of this area for statistical science.

Approach toward footstep planning considering the walking period: Optimization-based fast footstep planning for humanoid robots

  • Lee, Woong-Ki;Kim, In-Seok;Hong, Young-Dae
    • ETRI Journal
    • /
    • v.40 no.4
    • /
    • pp.471-482
    • /
    • 2018
  • This paper proposes the necessity of a walking period in footstep planning and details situations in which it should be considered. An optimization-based fast footstep planner that takes the walking period into consideration is also presented. This footstep planner comprises three stages. A binary search is first used to determine the walking period. The front stride, side stride, and walking direction are then determined using the modified rapidly-exploring random tree algorithm. Finally, particle swarm optimization (PSO) is performed to ensure feasibility without departing significantly from the results determined in the two stages. The parameters determined in the previous two stages are optimized together through the PSO. Fast footstep planning is essential for coping with dynamic obstacle environments; however, optimization techniques may require a large computation time. The two stages play an important role in limiting the search space in the PSO. This framework enables fast footstep planning without compromising on the benefits of a continuous optimization approach.

Multi-resolution Motion Estimation Algorithm Using Adaptive Search Region (적응적 탐색영역을 이용한 다중해상도 움직임 추정 방법)

  • 최정현;이경환;이법기;정원식;정태연;김덕규
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.24 no.8B
    • /
    • pp.1540-1548
    • /
    • 1999
  • We propose a multi-resolution motion estimation algorithm using adaptive search region. It is constructed in wavelet domain that a binary plane which represents the potential motion areas(PMA's) based on the temporal redundancy between video frames, and motion estimation is processed in the PMA's. We reduce the PMA's gradually as the resolution level is higher, considering the distribution of the energy in subband layers and the complexity. As compared with EMRME(enhanced multi-resolution motion estimation) method[7], simulation results show that computational amount and bit rate reduced to about 33 ~46 % and 10 ~l8% respectively in active image with similar PSNR, and computational amount reduced to about 37 ~65 % in small notion image with similar PSNR and bit rate.

  • PDF

A Content Retrieval Method Using Pictures Taken from a Display Robust to Partial Luminance Change (부분 휘도 변화에 강인한 영상 촬영 기반 콘텐츠 검색 방법)

  • Lee, Joo-Young;Kim, Youn-Hee;Nam, Je-Ho
    • Journal of Broadcast Engineering
    • /
    • v.16 no.3
    • /
    • pp.427-438
    • /
    • 2011
  • In this paper, we propose a content retrieval system using pictures taken from a display for more intelligent mobile services. We focus on the search robustness by minimizing the influence of photographing conditions such as changes in the illumination intensity. For an efficient search and precise detection, as well as robustness, we use a two-step comparison method based on indexing features and a binary map based on luminance and chrominance difference with the adjacent blocks. We also evaluate the proposed algorithm by comparing with the existing algorithms, and we show the content retrieval system that we've implemented using the proposed algorithm.