• Korea-Australia Rheology Journal
• /
• 제21권1호
• /
• pp.1-12
• /
• 2009

This paper reports the suitability of a domain decomposition technique for the hybrid simulation of dilute polymer solution flows using Eulerian Brownian dynamics and Radial Basis Function Networks (RBFN) based methods. The Brownian Configuration Fields (BCF) and RBFN method incorporates the features of the BCF scheme (which render both closed form constitutive equations and a particle tracking process unnecessary) and a mesh-less method (which eliminates element-based discretisation of domains). However, when dealing with large scale problems, there appear several difficulties: the high computational time associated with the Stochastic Simulation Technique (SST), and the ill-condition of the system matrix associated with the RBFN. One way to overcome these disadvantages is to use parallel domain decomposition (DD) techniques. This approach makes the BCF-RBFN method more suitable for large scale problems.

• 한국항해항만학회지
• /
• 제38권2호
• /
• pp.89-96
• /
• 2014

This paper presents an improvement for calculating method of astronomical ship position based on circle of equal altitude equation. In addition, to enhance the accuracy of ship position achieved from solving equation system, the authors used singular value decomposition (SVD) in least square method instead of normal decomposition. In maths, the SVD was proved more numerically stable than normal decomposition. Therefore, the solution of equation system will be more efficient and the result would be more accurate than previous methods. By proposal algorithm, a computer program have been developed to help the navigators in calculating directly ship position when the modern equipment has failure. Finally, some of experiments are carried out to verify effectiveness of proposed algorithm, the results show that the accuracy of ship position based on new method is better than the intercept method.

• 한국소음진동공학회:학술대회논문집
• /
• 한국소음진동공학회 2006년도 춘계학술대회논문집
• /
• pp.629-633
• /
• 2006

We investigated a new longitudinal acceleration wave decomposition method in time domain. The proposed method separates up- and down-stream waves with an axial strain and axial acceleration measured at a single point on the transmission path. The advantages such as low computation load and easy implementation would be possible by developing time domain under the following assumptions; low frequency range, uniform cross sectional area and elastic wave propagation. We confirmed the feasibility and performance of the method through experiment using Split Hopkinson Pressure Bar (SHPB). The method can be effective in several applications, including active vibration control with wave view point, where real time wave decomposition is necessary.

• 한국정보처리학회논문지
• /
• 제2권3호
• /
• pp.299-313
• /
• 1995

객체 지향 설계 방법은 프로그램을 객체로 분해하고, 그들 사이의 관계를 설정하 는 과정으로 기존의 시스템이 수행하는 기능 중심 방법과 달리 취급하는 객체를 중심 으로 모듈을 분해하는 기법이다. 그러나 기존의 객체 지향 설계 방법은 모듈 설계 방 법과 분해 기준이 모호하고 미흡하기 때문에 객체 지향 소프트웨어를 전체 시스템 단 위로 구현해야 하고, 하나의 소프트웨어 컴포넌트를 이해하기 위해서는 전체적인 객체 설계 모델 및 응용 프로그램을 분석해야 하는 많은 문제점이 발생한다. 따라서 본 논 문에서는 객체 지향 설계를 위한 모듈 분해 기준을 정형화 하고, 이를 이용한 객체 모 듈 설계 절차를 제시하여, 규모가 크고 복잡한 시스템을 개발하는데 있어 실용성과 시 스템 개발 후 유지보수를 원활하게 할 수 있도록 한다. 그리고 본 논문의 모듈 분해 기준을 실 시스템에 적용한 사례를 통하여 설계 모델과 구현 모델간의 일치성을 보이 고자 한다.

• Wind and Structures
• /
• 제36권1호
• /
• pp.61-73
• /
• 2023

In this article, a novel structural modal parameters identification methodology is developed to determine the natural frequencies and damping ratios of civil structures based on the symplectic geometry mode decomposition (SGMD) approach. The SGMD approach is a new decomposition algorithm that can decompose the complex response signals with better decomposition performance and robustness. The novel method firstly decomposes the measured structural vibration response signals into individual mode components using the SGMD approach. The natural excitation technique (NExT) method is then used to obtain the free vibration response of each individual mode component. Finally, modal natural frequencies and damping ratios are identified using the direct interpolating (DI) method and a curve fitting function. The effectiveness of the proposed method is demonstrated based on numerical simulation and field measurement. The structural modal parameters are identified utilizing the simulated non-stationary responses of a frame structure and the field measured non-stationary responses of a supertall building during a typhoon. The results demonstrate that the developed method can identify the natural frequencies and damping ratios of civil structures efficiently and accurately.

• 한국항공우주학회지
• /
• 제31권5호
• /
• pp.18-24
• /
• 2003

많은 공학 시스템은 여러 개의 해석모듈들이 다양한 데이터의 입출력 관걔로 연관된 형태로 모델링 된다. 이와 같은 복잡한 하나의 시스템을 몇 개의 시스템으로 나누어 해석 및 다분야통합최적설계를 수행하면 계산소요시간 및 병렬처리 측면에서 효율적인 것으로 알려져 있다. 따라서 전체 시스템을 몇 개의 하부시스템으로 분해하는 방법에 대한 연구가 진행되어 왔으나 하부시스템 간의 계산소요시간 분배에 대한 고려가 없이 설계자가 임의로 하부시스템의 크기를 자동으로 결정하도록 하였다. 이를 위하여 적응분해기법은 유전알고리듬을 사용하였고, 기존의 병렬분해기법에서 사용된 염색체에 시스템분해 위치를 나타내는 정보를 추가한 확장염색체를 제안하여 병렬처리에 적합한 시스템분해기법을 구현하였다. 그리고, 항공기 설계 문제와 헬기 설계 문제에 적응분해기법을 적용하여 개발된 알고리듬의 효율성을 보였다.

• 한국경영과학회지
• /
• 제15권1호
• /
• pp.23-35
• /
• 1990

A mathematical model for a dynamic capacitate facility location problem is formulated by a mixed integer problem. The objective of the model is to minimize total discounted costs that include fixed charges and distributed costs. The Cross Decomposition method of Van Roy is extended and applied to solve the dynamic capacitated facility location problem. The method unifies Benders Decomposition and Lagrangean relaxation into a single framework. It successively solves a transportation problem and a dynamic uncapacitated facility location problem as two subproblems. Computational results are compared with those of general mixed integer programming.

• 제어로봇시스템학회논문지
• /
• 제10권4호
• /
• pp.364-370
• /
• 2004

In this paper, we propose a FDI method, which comes from singular value decomposition of measurement matrix fur redundant sensors. We analyze the performance of the proposed FDI method by comparing with the GLT method in two ways such as FDI performance and GN＆C performance. Also, we propose a GN＆C performance index by combining FDI and GN＆C performance.

• 한국CDE학회논문집
• /
• 제19권1호
• /
• pp.50-60
• /
• 2014

In this paper, we propose a non-overlapping volume decomposition method that decomposes a solid model into non-overlapped volumes. The non-overlapping volume decomposition finds non-overlapped volumes from maximum volumes. After introducing the concept of the non-overlapping volume decomposition, we discuss technical issues and solutions for them. The non-overlapping volume decomposition is verified by the experiments with a prototype system. From the experiments, it was found that the non-overlapping volume decomposition shows better result than maximum volume decomposition from the view point of design feature recognition.

• 한국지능시스템학회:학술대회논문집
• /
• 한국퍼지및지능시스템학회 2003년도 ISIS 2003
• /
• pp.364-367
• /
• 2003

In this study, we develop a method for recognizing face images by combining wavelet decomposition, fisherface method, and fuzzy integral. The proposed approach comprises of four main stages. The first stage uses the wavelet decomposition. As a result of this decomposition, we obtain four subimages. The second stage of the approach applies a fisherface method to these four subimage sets. The two last phases are concerned with the generation of the degree of fuzzy membership and the aggregation of the individual classifiers by means of the fuzzy integral. The experimental results obtained for the CNU and Yale face databases reveal that the approach presented in this study yields better classification performance in comparison to the results produced by other classifiers.