• Title/Summary/Keyword: Optimization problems

Search Result 2,436, Processing Time 0.035 seconds

Efficient Handwritten Character Verification Using an Improved Dynamic Time Warping Algorithm (개선된 동적 타임 워핑 알고리즘을 이용한 효율적인 필기문자 감정)

  • Jang, Seok-Woo;Park, Young-Jae;Kim, Gye-Young
    • Journal of the Korea Society of Computer and Information
    • /
    • v.15 no.7
    • /
    • pp.19-26
    • /
    • 2010
  • In this paper, we suggest a efficient handwritten character verification method in on-line environments which automatically analyses two input character string and computes their similarity degrees. The proposed algorithm first applies the circular projection method to input handwritten strings and extracts their representative features including shape, directions, etc. It then calculates the similarity between two character strings by using an improved dynamic time warping (DTW) algorithm. We improved the conventional DTW algorithm efficiently through adopting the branch-and-bound policy to the existing DTW algorithm which is well-known to produce good results in the various optimization problems. The experimental results to verify the performance of the proposed system show that the suggested handwritten character verification method operates more efficiently than the existing DTW and DDTW algorithms in terms of the speed.

Topology Design for Energy/Latency Optimized Application-specific Hybrid Optical Network-on-Chip (HONoC) (특정 용도 하이브리드 광학 네트워크-온-칩에서의 에너지/응답시간 최적화를 위한 토폴로지 설계 기법)

  • Cui, Di;Lee, Jae Hoon;Kim, Hyun Joong;Han, Tae Hee
    • Journal of the Institute of Electronics and Information Engineers
    • /
    • v.51 no.11
    • /
    • pp.83-93
    • /
    • 2014
  • It is a widespread concern that electrical interconnection based network-on-chip (NoC) will ultimately face the limitation in communication bandwidth, transmission latency and power consumption in the near future. With the development of silicon photonics technology, a hybrid optical network-on-chip (HONoC) which embraces both electrical- and optical interconnect, is emerging as a promising solution to overcome these problems. Today's leading edge systems-on-chips (SoCs) comprise heterogeneous many-cores for higher energy efficiency, therefore, extended study beyond regular topology based NoC is required. This paper proposes an energy and latency optimization topology design technique for HONoC taking into account the traffic characteristics of target applications. The proposed technique is implemented with genetic algorithm and simulation results show the reduction by 13.84% in power loss and 28.14% in average latency, respectively.

Self-tuning of Operator Probabilities in Genetic Algorithms (유전자 알고리즘에서 연산자 확률 자율조정)

  • Jung, Sung-Hoon
    • Journal of the Institute of Electronics Engineers of Korea CI
    • /
    • v.37 no.5
    • /
    • pp.29-44
    • /
    • 2000
  • Adaptation of operator probabilities is one of the most important and promising issues in evolutionary computation areas. This is because the setting of appropriate probabilities is not only very tedious and difficult but very important to the performance improvement of genetic algorithms. Many researchers have introduced their algorithms for setting or adapting operator probabilities. Experimental results in most previous works, however, have not been satisfiable. Moreover, Tuson have insisted that “the adaptation is not necessarily a good thing” in his papers[$^1$$^2$]. In this paper, we propose a self-tuning scheme for adapting operator probabilities in genetic algorithms. Our scheme was extensively tested on four function optimization problems and one combinational problem; and compared to simple genetic algorithms with constant probabilities and adaptive genetic algorithm proposed by Srinivas et al[$^3$]. Experimental results showed that our scheme was superior to the others. Our scheme compared with previous works has three advantages: less computational efforts, co-evolution without additional operations for evolution of probabilities, and no need of additional parameters.

  • PDF

Visualizing test on the pass-through and collision characteristics of coarse particles in a double blade pump

  • Tan, Minggao;Lian, Yichao;Liu, Houlin;Wu, Xianfang;Ding, Rong
    • International Journal of Naval Architecture and Ocean Engineering
    • /
    • v.10 no.1
    • /
    • pp.1-8
    • /
    • 2018
  • As the key equipment in deep ocean mining, the slurry pump suffers from wear and blocking problems. In this paper, high-speed photography technique is applied to track the movement rule of single particle of the coarse particle solid-liquid two-phase flow in a double blade slurry pump. The influences of particle diameter and particle density on the pass-through and collision characteristics of particles are analyzed as well. The results show that the average of the passing pump time first decreases and then increases when the particle diameter increases. The average of the passing pump time decreases by 22.7%, when the particle density increases from $1.09g/cm^3$ to $1.75g/cm^3$. Besides, the particle density has great influence on the location where the particle hits the tongue. Most particles of $1.09g/cm^3$ hit the tongue on the left side, while collision location of particles of $1.75g/cm^3$ is mainly on the top and at the right side of the tongue. The research can provide a basis for the optimization design of slurry pump in deep ocean mining system.

Robust Intelligent Digital Redesign of Nonlinear System with Parametric Uncertainties (불확실성을 갖는 비선형 시스템의 강인한 지능형 디지털 재설계)

  • Sung, Hwa-Chang;Joo, Young-Hoon;Park, Jin-Bae
    • Journal of the Korean Institute of Intelligent Systems
    • /
    • v.16 no.2
    • /
    • pp.138-143
    • /
    • 2006
  • This paper presents intelligent digital redesign method for hybrid state space fuzzy-model-based controllers. For effectiveness and stabilization of continuous-time uncertain nonlinear systems under discrete-time controller, Takagi-Sugeno(TS) fuzzy model is used to represent the complex system. And global approach design problems viewed as a convex optimization problem that we minimize the error of the norm bounds between nonlinearly interpolated linear operators to be matched. Also, by using the bilinear and inverse bilinear approximation method, we analyzed nonlinear system's uncertain parts more precisely. When a sampling period is sufficiently small, the conversion of a continuous-time structured uncertain nonlinear system to an equivalent discrete-time system have proper reason. Sufficiently conditions for the global state-matching of the digitally controlled system are formulated in terms of linear matrix inequalities (LMIs). Finally, a TS fuzzy model for the chaotic Lorentz system is used as an . example to guarantee the stability and effectiveness of the proposed method.

A Study On Construction Project Expected Effect Collaboration Business Design Management (협업 설계관리를 통한 건설 프로젝트 기대효과에 관한 연구)

  • Nam, Hye-Won;Lee, Jong-Sik;Chun, Jae-Youl
    • Proceedings of the Korean Institute Of Construction Engineering and Management
    • /
    • 2007.11a
    • /
    • pp.589-592
    • /
    • 2007
  • While it is these days, and is increased importance as opposed to design management in managing a construction business necessity as opposed to collaboration business design management between collaboration business business company is regarded as important. An object was put in deriving a flow of a design process about the design management business and a grasp, management element as opposed to management by reason of the first, building design business ability improvement by a study of a book hereby, and an alternative plan of collaboration business design management for use in design optimization of difficulty of a disagreement, workshop modification city design information chase between books by lack of collaboration business between things of each minimization, company was shown with, air in a base in problems grasp as opposed to a collaboration business design by the second" work-site operations and a design process management element. Therefore, this thesis is going to show expected effect of a project about collaboration business design management through systematic practical use about a collaboration business design.

  • PDF

A Study on Methodology for Standardized Platform Design to Build Network Security Infrastructure (네트워크 보안 인프라 구성을 위한 표준화된 플랫폼 디자인 방법론에 관한 연구)

  • Seo, Woo-Seok;Park, Jae-Pyo;Jun, Moon-Seog
    • The Journal of the Korea institute of electronic communication sciences
    • /
    • v.7 no.1
    • /
    • pp.203-211
    • /
    • 2012
  • Network security infrastructure is constantly developing based on the combination and blending of various types of devices. From the form of distributed control, the phased defense policy such as fire walls, virtual private communication network, invasion prevention system, invasion detection system, corporate security management, and TSM (Telebiometrics System Mechanism), now it consolidates security devices and solutions to be developed to the step of concentration and artificial intelligence. Therefore, this article suggests network security infrastructure design types concentrating security devices and solutions as platform types and provides network security infrastructure design selecting methodology, the foundational data to standardize platform design according to each situation so as to propose methodology that can realize and build the design which is readily applied and realized in the field and also can minimize the problems by controlling the interferences from invasion.

A FINITE ELEMENT STRESS ANALYSIS OF THE STRESS DISTRIBUTION AND THE SHOCK ABSORPTION IN AN OSSEOINTEGRATED IMPLANT-NATURAL TOOTH SUPPORTED FIXED PARTIAL DENTURE (골유착성 임프란트와 자연치를 이용한 고정성 국소의치에서 응력분산 및 충격흡수에 관한 유한요소법적 응력분석)

  • Jeong Chang-Mo;Lee Ho-Yong
    • The Journal of Korean Academy of Prosthodontics
    • /
    • v.30 no.4
    • /
    • pp.582-610
    • /
    • 1992
  • The long-term success of any dental implant is dependent upon the optimization of stresses which occur during oral function and parafunction. Especially, it has been suggested that there is an unique set of problems associated with joining an osseointegrated implant and a natural tooth with a fixed partial denture. For this particular case, although many literatures suggest different ways to avoid high stress concentrations on the bone surrounding the implant under static and dynamic loading conditions, but few studies on the biomechanical efficacy of each assertion have been reported. The purpose of this investigation was to evaluate the efficacies of clinically suggested methods on stress distribution under static load and shock absorption under dynamic load, using two dimensional finite element method. In FEM models of osseointegrated implant-natural tooth supported fixed partial dentures, calculations were made on the stresses in surrounding bone and on the deflections of abutments and superstructure, first, to compare the difference in stress distribution effects under static load by the flexure of fastening screw or prosthesis, or intramobile connector, and second, to compare the difference in the shock absorption effects under dynamic load by intramobile connector or occlusal veneering with composite resin. The results of this analysis suggest that : 1. Under static load condition, using an implant design with fastenign screw connecting implant abutment and prosthesis or increasing the flexibility of fastening screw, or increasing the flexibility of prosthesis led to the .increase in height of peak stresses in cortical bone surrounding the implant, and has little effect on stress change in bone around the natural tooth. 2. Under static load condition, intramobile connector caused the substantial decrease in stress concentration in cortical bone surrounding the implant and the slight increase in stress in bone around the natural tooth. 3. Under dynamic load condition, both intramobile connector and composite resin veneering showed shock absorption effect on bone surrounding the implant and composite resin veneering had a greater shock absorption effect than intramobile connector.

  • PDF

An Improved Robust Fuzzy Principal Component Analysis (잡음 민감성이 개선된 퍼지 주성분 분석)

  • Heo, Gyeong-Yong;Woo, Young-Woon;Kim, Seong-Hoon
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.14 no.5
    • /
    • pp.1093-1102
    • /
    • 2010
  • Principal component analysis (PCA) is a well-known method for dimension reduction while maintaining most of the variation in data. Although PCA has been applied to many areas successfully, it is sensitive to outliers. Several variants of PCA have been proposed to resolve the problem and, among the variants, robust fuzzy PCA (RF-PCA) demonstrated promising results. RF-PCA uses fuzzy memberships to reduce the noise sensitivity. However, there are also problems in RF-PCA and the convergence property is one of them. RF-PCA uses two different objective functions to update memberships and principal components, which is the main reason of the lack of convergence property. The difference between two functions also slows the convergence and deteriorates the solutions of RF-PCA. In this paper, a variant of RF-PCA, called RF-PCA2, is proposed. RF-PCA2 uses an integrated objective function both for memberships and principal components. By using alternating optimization, RF-PCA2 is guaranteed to converge on a local optimum. Furthermore, RF-PCA2 converges faster than RF-PCA and the solutions found are more similar to the desired solutions than those of RF-PCA. Experimental results also support this.

Verification for Multithreaded Java Code using Java Memory Model (자바 메모리 모델을 이용한 멀티 스레드 자바 코드 검증)

  • Lee, Min;Kwon, Gi-Hwon
    • The KIPS Transactions:PartD
    • /
    • v.15D no.1
    • /
    • pp.99-106
    • /
    • 2008
  • Recently developed compilers perform some optimizations in order to speed up the execution time of source program. These optimizations require the reordering of the sequence of program statements. This reordering does not give any problems in a single-threaded program. However, the reordering gives some significant errors in a multi-threaded program. State-of-the-art model checkers such as JavaPathfinder do not consider the reordering resulted in the optimization step in a compiler since they just consider a single memory model. In this paper, we develop a new verification tool to verify Java source program based on Java Memory Model. And our tool is capable of handling the reordering in verifying Java programs. As a result, our tool finds an error in the test program which is not revealed with the traditional model checker JavaPathFinder.