• Steel and Composite Structures
• /
• 제27권3호
• /
• pp.297-310
• /
• 2018

A simple and efficient numerical optimization approach for the lightweight optimal design of composite laminated beams is presented in this paper. The proposed procedure is a combination between the finite element method (FEM) and a global optimization algorithm developed recently, namely Jaya. In the present procedure, the advantages of FEM and Jaya are exploited, where FEM is used to analyze the behavior of beam, and Jaya is modified and applied to solve formed optimization problems. In the optimization problems, the objective aims to minimize the overall weight of beam; and fiber volume fractions, thicknesses and fiber orientation angles of layers are selected as design variables. The constraints include the restriction on the first fundamental frequency and the boundaries of design variables. Several numerical examples with different design scenarios are executed. The influence of the design variable types and the boundary conditions of beam on the optimal results is investigated. Moreover, the performance of Jaya is compared with that of the well-known methods, viz. differential evolution (DE), genetic algorithm (GA), and particle swarm optimization (PSO). The obtained results reveal that the proposed approach is efficient and provides better solutions than those acquired by the compared methods.

• 한국콘크리트학회:학술대회논문집
• /
• 한국콘크리트학회 2010년도 춘계 학술대회 제22권1호
• /
• pp.139-140
• /
• 2010

콘크리트 격납구조물의 돔과 링빔은 서로 접합된 상태로 단면력 분포에 있어 상호 영향을 미치기 때문에 연계 해석이 필요하다. 이 연구에서는 축대칭 회전쉘의 막이론을 적용하여 본설계시의 유한요소해석에 앞서 돔과 링빔의 초기 형상이나 링빔의 프리스트레스 수준을 효율적으로 결정할 수 있는 기법을 제안하였다.

• 한국소음진동공학회:학술대회논문집
• /
• 한국소음진동공학회 2011년도 추계학술대회 논문집
• /
• pp.279-284
• /
• 2011

The calculation of Zwicker's loudness which is needed for multiple frequency response with a fine frequency resolution using the finite element (FE) procedure usually requires significant computation time since a numerical solution must be obtained for each considered frequency. Furthermore, if the analysis is the basis for an iterative optimization procedure this approach imposes high computational cost. In this work, we present an efficient approach for obtaining Zwicker's loudness via the Pad$\acute{e}$ approximants and applying in an acoustical topology optimization procedure. The paper is focused on an efficient and accurate calculation of Zwicker's loudness, design sensitivity analysis, and the acoustical topology optimization method by using Pad$\acute{e}$ approximants. The paper compares the efficient algorithm to results obtained by a standard FEM. Comparison are made both in terms of accuracy and in terms of CPU-times needed for the calculation.

• 대한교통학회지
• /
• 제1권1호
• /
• pp.28-42
• /
• 1983

In recent years, significant advances have been made enabling travel demand analysis and network design methods to be used as increasingly realistic evaluation tools. What has been lacking is the integration of travel demand analysis with network design models. This paper reviews some of advanced (integrated) modeling approaches and presents future research directions of integrated modeling system. To design urban transportation networks, it is argued that the travelers' free choice of mode, destination and route should be introduced into transportation network design procedure instead of assuming that trips from a zone to a workplace are fixed or deriving them in a normative procedure to achieve hypothetical system optima.

• 한국농공학회:학술대회논문집
• /
• 한국농공학회 1999년도 Proceedings of the 1999 Annual Conference The Korean Society of Agricutural Engineers
• /
• pp.219-224
• /
• 1999

In this study New design automation method of R/C structure based on the finite element method and the analogy evolution ary procedure was developed . This system is the efficient tool to support Reinforcement Arrangement of R/C structure. The anology evolutionary procecure is similar to the evolutionary procedure proposed by Xie and Steven.

• 대한전기학회논문지:전력기술부문A
• /
• 제48권3호
• /
• pp.263-269
• /
• 1999

In this paper, an unifying design algorithm is presented for efficient digital implementation of continuous PID controller using general discrete orthogonal functions. The proposed algorithm is an algebraic method to determine controller parameters, which can unify controller design procedures divided into three ways. A set of linear equations for the controller design are derived from simple algebraic transformation based on general discrete orthogonal functions. By solving these equations, all of the controller parameters can be determined directly and simultaneously, which thus makes the design procedure systematic and straightforward. It does not involve any trial and error procedure, hence the difficulty of conventional approach can be avoided. The simulation results and discussions are given to demonstrate the efficiency of the proposed method.

• 한국정밀공학회지
• /
• 제15권5호
• /
• pp.161-166
• /
• 1998

As a part of the configuration design expert system of machine tools, inference mechanisms are constructed in this paper. In addition to procedural inference, the method of multivariable inference is considered as an efficient approach to deal with the cases of highly coupled condition. We propose a generalized multi-variable inference procedure. The procedure is applied to the type selection module of the configuration design expert system of machine tools in order to demonstrate the efficiency and validity.

• 한국정보기술응용학회:학술대회논문집
• /
• 한국정보기술응용학회 2005년도 6th 2005 International Conference on Computers, Communications and System
• /
• pp.331-334
• /
• 2005

This paper suggests the Ethernet aggregation to XGMII framing procedure (EAXFP) mechanism to economically combine the traffic adaptation technology with the link aggregation method in designing 10 Gigabit Ethernet (10 GbE) interfaces. This design sidesteps the data-loss issues that can result from designing an interface with only one link. The most critical issue in relation to the link aggregation interface is the algorithm used to control frame distribution between the ten ports. The proposed EAXFP mechanism offers an efficient link aggregation method as well as an efficient frame distribution algorithm, which maximize the throughout of the 10 GbE interface. In the experiment and analysis of the proposed mechanism, it was also discovered that the 10 GbE interface that uses the proposed EAXFP mechanism significantly reduced the packet loss rate. When there will be heavy traffic loads come about in the future, the proposed EAXFP mechanism assures an efficient and economical transmission performance on the router system.

• 한국전산유체공학회:학술대회논문집
• /
• 한국전산유체공학회 1997년도 추계 학술대회논문집
• /
• pp.126-130
• /
• 1997

A new and efficient method is presented for design optimization, which is based on a computational fluid dynamics (CFD). The method is applied to design an airfoil configuration. The Navier-Stokes equations are solved for the viscous analysis of the flow, which provides the object function. The CFD analysis is then coupled with the optimization procedure that used a conjugate gradient method. During the one-dimensional search of the optimization procedure, an approximate flow analysis based on a first-order Taylor series expansion is used to reduce the computational cost, (This study is supported by Korean Ministry of Education through Research Fund)

• International Journal of Automotive Technology
• /
• 제7권1호
• /
• pp.61-68
• /
• 2006

In design of the friction clutches of automobiles, knowledge on the thermo-elasticity a priori is very informative in the initial design stage. Especially, the precise prediction technique of maximum temperature and stress should be requested in design of mechanical clutches for their durability and compactness. In this study, an efficient and reliable analysis technique for the design of the mechanical clutches by using computer modeling and numerical method was developed. A commercial software STAR-$CD^{TM}$ was used to find the convective heat-transfer coefficients. MSC/$NASTRAN^{TM}$ software was followed to predict the temperature of clutch with utilization of estimated coefficients. Some experiments were also performed with a dynamometer to verify the procedure and calibrate the thermal load. As a conclusion, a design procedure, including numerical steps and experimental techniques for calibration, was proposed.