• International Journal of Fuzzy Logic and Intelligent Systems
• /
• v.8 no.4
• /
• pp.264-269
• /
• 2008

In this paper, two neural networks as a material model, which are based on the state-space method, have been proposed. One outputs the rates of inelastic strain and material internal variables whereas the outputs of the other are the next state of the inelastic strain and material internal variables. Both the neural networks were trained using input-output data generated from Chaboche's model and successfully converged. The former neural network could reproduce the original stress-strain curve. The neural network also demonstrated its ability of interpolation by generating untrained curve. It was also found that the neural network can extrapolate in close proximity to the training data.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.18 no.3 s.39
• /
• pp.85-97
• /
• 1990

To understand the parks and leisure recreation environments of United States, some major areas are studied with the brief history of R & P area. development Those are 1) National Park System and National Park Service 2) ORRRC and BOR 3) Education of the Recreation & Park professions. Some findings of this study can be summarized as follows : 1. In United States, R & P area has been developed on the firm base of 'Publicity'. Central Park as a public park, National Park Service and Bureau of Outdoor Recreation as Federal organization have led this concept. 2. Major recreational resources - natural, cultural and historical etc-have converged into National Park System. On that, conservation and recreation use of those resources are possible in balance. 3. Establishment of the R & P area in the early stage made a great contribution to educate professionals. And this situation has been so helpful for balanced development of the area.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2002.05a
• /
• pp.152-156
• /
• 2002

인터넷 기반의 전화서비스 연구가 진행이 되면서, 음성과 데이터의 통합을 이루고자 하는 연구가 진행이 되었으며, 기존 데이터 통신망은 통합된 망 환경으로 진화하게 되었다. 통합망에서 음성 서비스를 위한 호 제어기는 다양한 단말의 요구 조건을 수용하여야 하며, 특히 음성 서비스 제어를 위한 표준화된 프로토콜들을 수용할 수 있어야 한다. 본 논문에서는 통합망에서 다양한 프로토콜을 수용할 수 있는 통합망 호 제어기의 구조를 제시한다. 특히 데이터베이스 관리 시스템을 이용하여 망 관리 정보기반의 호 제어기를 설계하며, 망 관리 정보를 바탕으로 호 제어기 기능 블록들이 운용이 되도록 설계한다. 본 연구의 결과로 제시된 통합 호 제어기의 모델을 바탕으로 구내망의 호 제어기를 개발하고자한다.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.62 no.3
• /
• pp.293-299
• /
• 2013

Power system technologies in the area of smart grid are being converged with communication system technologies or information technologies(IT). This interdisciplinary action affects on two parts vigorously so that IT has become a essential part of power industry. But terminologies of two parts are confused and it is necessary that these are standardized to develop the industry. The interpretation works with scientific and technological standard of the smart grid terminologies which are IEC TC 57 glossary and non-glossary terminologies are introduced. Based on the interpretation works of the smart grid terminologies, an online terminology information system for the standardization of smart grid terminologies is proposed. The system provides the capability of collection and delivery of academic society opinions for the selected and interpreted terminologies.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2002.11b
• /
• pp.1559-1562
• /
• 2002

이동 망 및 인터넷의 폭발적인 확장과 망 통합의 가속화에 따라 다양한 서비스 기능 및 데이터의 결합이 필수적인 서비스가 요구되고 있으나, 기존의 지능 망 기반 구조로는 이러한 서비스에 대한 대처하기가 현실적으로 불가능하다 이에 대한 해결책으로써 국제 표준화 포럼인 Parlay 를 중심으로 개방형 기술 기반의 서비스 API(Application Programming interface)를 개발해 오고 있다. 본 논문에서는 개방형 서비스 API 의 표준 규격인 Parlay/OSA API 구조에 대해서 살펴본다. IP 기반의 통합 망에서의 본 API 적용을 위한 망 구조를 제시하고, 실제 서비스 예를 대상으로 망 내각 노드 간의 처리 흐름 및 Parlay/OSA API와 망 내 신호 방식간 연동방법 등을 제안하였다.

• Proceedings of the KIEE Conference
• /
• 2000.07d
• /
• pp.3118-3120
• /
• 2000

In this paper. a stable IIR adaptive filter for active noise control is proposed. The IIR filter structure is more effective when acoustic feedback exists, in which case an order of a FIR filter must be very large if some of the poles of the ideal control filter are near the unit circle. But the IIR filter may have stability problems especially when the adaptive algorithm is not converged. A stabilizing procedure for IIR adaptive filter is presented in this paper, and computer simulation is performed to show the effectiveness of proposed schemes.

• Proceedings of the Computational Structural Engineering Institute Conference
• /
• 2000.10a
• /
• pp.331-338
• /
• 2000

In this paper, a non-linear finite element formulation for the spatial cable-net structures is simulated and using this formulation, the characteristics of structural behaviors for the elastic catenary cable are examined In the simulating procedure for the elastic catenary cable, nodal forces and tangential stiffness matrices are derived using catenary parameters of the exact solutions by a governing differential equation of catenary cable, cable self-weights and unstressed cable length. Dynamic Relaxation Method that considers kinetic damping is used for the structure analysis and Newton Raphson Method is used to verify the accuracy of solutions. In the analysis of two dimensional cable, the results obtain from the elastic catenary elements are shown more accurate than does of truss elements and in the case of spatial cable-net structures, Dynamic Relaxation Method is more stable to be converged than Newton Raphson Method.

• Transactions of the Korean Society of Machine Tool Engineers
• /
• v.18 no.1
• /
• pp.22-28
• /
• 2009

In order to optimize the polishing process, Run to Run control scheme has been applied to the micro mold polishing in this study. Also, to fully understand the effect of parameters on the surface roughness a design of experiment is performed. By linear approximation of main factors such as gap and rotational speed of micro quill, EWMA (Exponential Weighted Moving Average) gradual mode controller is adopted as a optimizing tool. Consequently, the process converged quickly at a target value of surface roughness Ra 10nm and Rmax 50nm, and was hardly affected by unwanted process noises like initial surface quality and wear of magnetic abrasives.

• International Journal of Naval Architecture and Ocean Engineering
• /
• v.8 no.4
• /
• pp.320-329
• /
• 2016

An implicit method of solving the six degree-of-freedom rigid body motion equations based on the second order Adams-Bashforth-Moulten method was utilised as an improvement over the leapfrog scheme by making modifications to the rigid body motion solver libraries directly. The implementation will depend on predictor-corrector steps still residing within the hybrid Pressure Implicit with Splitting of Operators - Semi-Implicit Method for Pressure Linked Equations (PIMPLE) outer corrector loops to ensure strong coupling between fluid and motion. Aitken's under-relaxation is also introduced in this study to optimise the convergence rate and stability of the coupled solver. The resulting coupled solver ran on a free floating object tutorial test case when converged matches the original solver. It further allows a varying 70%-80% reduction in simulation times compared using a fixed under-relaxation to achieve the required stability.

• Journal of Institute of Control, Robotics and Systems
• /
• v.12 no.6
• /
• pp.561-567
• /
• 2006

This paper deals with a fuzzy controller using IA(Immune Algorithm) for Trajectory Tracking of 2-DOF WMR(Wheeled Mobile Robot). The global inputs to the WMR are reference position and reference velocity, which are time variables. The global output of WMR is a current position. The tracking controller makes position error to be converged 0. In order to reduce position error, a compensation velocities on the track of trajectory is necessary. Therefore, a FIAC(Fuzzy-IA controller) is proposed to give velocity compensation in this system. Input variables of fuzzy part are position errors in every sampling time. The output values of fuzzy part are compensation velocities. IA are implemented to adjust the scaling factor of fuzzy part. The computer simulation is performed to get the result of trajectory tracking and to prove efficiency of proposed controller.