• The Korean Journal of Applied Statistics
• /
• v.18 no.3
• /
• pp.617-625
• /
• 2005

We usually use orthogonal designs-orthogonal array of strength 2 as orthogonal arrays. It was shown that fractional factorial plaits represented by orthogonal arrays of strength 3 are universally optimal under the additive motels that includes the mean, all main effects and all two-factor interactions. Therefore, we need the measure for evaluating the orthogonal array of strength 3. We can extend this measure as the measure for evaluating the orthogonal array of strength t($\ge$ 2).

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.25 no.10
• /
• pp.1621-1626
• /
• 2001

The structural optimization have been carried out in the continuous design space or in the discrete design space. Methods fur discrete variables such as genetic algorithms , are extremely expensive in computational cost. In this research, an iterative optimization algorithm using orthogonal arrays is developed for design in discrete space. An orthogonal array is selected on a discrete des inn space and levels are selected from candidate values. Matrix experiments with the orthogonal array are conducted. New results of matrix experiments are obtained with penalty functions leer constraints. A new design is determined from analysis of means(ANOM). An orthogonal array is defined around the new values and matrix experiments are conducted. The final optimum design is found from iterative process. The suggested algorithm has been applied to various problems such as truss and frame type structures. The results are compared with those from a genetic algorithm and discussed.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.19 no.4
• /
• pp.41-46
• /
• 2019

This paper is analysis on usefulness of Microstrip patch antenna design using Taguchi's Orthogonal array. For comparison, the shape of U-slot and Feed line elements are decided as a parameter in Microstrip patch antenna. And all the possible result of 19,683 times simulation using parameter sweep and the result of Taguchi's orthogonal arrays are compared. The simulation of Parameter sweep and Orthogonal arrays has 3.7% error on 10dB Bandwidth. Finally, It is identified that 19,683 times parameter sweep simulation can be reduced to 27 times with Taguchi's orthogonal arrays but still it represents antenna parameter characters well.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2005.05a
• /
• pp.372-378
• /
• 2005

Finite element analysis of concrete slab system in apartment building was executed using the tables of orthogonal arrays, and optimal design process was proposed. At first, experimental results show that sound peak components to influence the overall level and the rating of floor impact sound insulation were coincident with natural frequencies of the reinforced concrete slab. Finite element model of concrete slab was compared with experimental results, and well corresponded with an error of less than 10%. The tables of orthogonal arrays were used for finite element analysis with 8 factors. 3 related to material properties and 5 related to slab shape parameters and its results were analyzed by statistical method, ANOVA. The most effective factor among them was slab thickness, and main effect factor from slab shape parameters was different from each natural frequency. The interaction was found in the higher mode over $3^{rd}$ natural frequency. From main effect plot and interaction plot, the optimal design factor to increase the natural frequency was determined.

• Journal of the Korean Society for Precision Engineering
• /
• v.17 no.6
• /
• pp.69-75
• /
• 2000

At the stage of initial design, prototypes are needed for engineering and aesthetic purposes. In order to get a fast and non-expensive prototype, designers prefer rapid prototyping(RP) to any other means. In driving a 3D CAD model into rapid prototyping, sectioning the model is essential and there are two negotiation-needed targets, enhancing accuracy while taking less build-time, which makes adaptive slicing taken into account. In spite of the advantages of adaptive slicing, it is not yet applied to real RP machines because of the limits of hardwares. In this thesis, a new slicing algorithm which (1)uses several values of thickness available in a RP machine. (2)determines total number of layers to make the prototype within the intended time and (3)arranges the layers using orthogonal arrays to minimize the volume error caused by the difference between a given CAD model and a fabricated model is presented. And the algorithm is expected to have possibility of assisting RP machines to take the advantages of adaptive slicing.

• Journal of Korean Society for Quality Management
• /
• v.30 no.1
• /
• pp.133-143
• /
• 2002

We propose an optimal design to improve the muffler's capacity by reducing the noise of the intake system by adapting kriging method with the robust design. For the first stage of a design, the length and radius of each component of the current muffler system are selected as control factors. Then, the $L_18$ table of orthogonal arrays is adapted to extract the effective main factors. As the second stage, the $L_18$ table of orthogonal arrays using kriging method is adapted to take the significant factors into consideration. As an optimal design, the $L_18$ table of orthogonal arrays with main effects is proposed and the kriging method is adapted for more efficient design. The kriging method improves the performance of intake system.

• The Korean Journal of Applied Statistics
• /
• v.4 no.1
• /
• pp.47-63
• /
• 1991

Parameter design is the core of the Taguchi method, and its purpose is to design product or processes such that the performance of product becomes robust to noise. Taguchi recommends to use the so called orthogonal arrays for parameter design. The purpose of this paper is to clarify the principles involved in constructing the Taguchi orthogonal arrays. Understanding such principles may be useful for finding better ways of utilizing the Taguchi orthogonal arrays as well as for developing better experimental designs.

• The Korean Journal of Applied Statistics
• /
• v.7 no.2
• /
• pp.201-211
• /
• 1994

Ignoring interaction effects has been pointed out to be one of serious drawbacks in analysis of the parameter designs which are constructed by using orthogonal arrays. In this paper a detecting procedure of influential 2-factor inteactions with minimum expeimental runs is described, when each contrl factor has two levels. The presented method is based on the near orthogonal arrays which are very similar to orthogonal arrays in the statistical structure. And those arrarys are the same as trace-optimal balanced saturated two-level fractional factorial designs of resolution V.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.7 no.8
• /
• pp.208-215
• /
• 1999

Using the orthogonal arrays and the occupant analysis software based on the multi-body dynamics , two interactive design algorithms are proposed to improve the initial design of the occupant protection systems. Algorithm 1 sequentially moves the narrow design space within the upper and the lower design limit. Algorithm 2 sequentially reduces the relatively wide design space. Each design algorithm is composed of two levels . The first level is to improve the characteristics of the crash performance considering the noise factors. In order to obtain the robust design, the second level reduces the variations the noise factors. In order to obtain the robust design, the second level reduces the variations due to the tolerance of the design variable. To utilize the algorithm 1, HIC(Head Injury Criterion) , 3 msec criterion value of the chest acceleration and the femur load decreased by 27.4%, 10.4% and 55.8%, respectively. To utilizer the algorithm 2 , the results decreased by 38.0%, 10.5% and 3.0% , respectively.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.14 no.4
• /
• pp.123-131
• /
• 2006

The majority of pedestrian fatalities and injuries are caused by vehicle-pedestrian accidents. Recently, it has been recognized as a serious problem. Injuries of occupants in a vehicle have been decreased considerably. However, efforts for protection of pedestrians are still insufficient. These days, many advanced industries are striving for a better protection of pedestrians by using an active hood lift system, rather than reforming the existing structure. In this research, the active hood lift system is designed to enhance the performance for protection. The active hood lift system is analyzed by using the nonlinear finite element method. An optimization problem is formulated by incorporation of the analysis results. Orthogonal arrays are utilized to solve the formulated problem. An iterative optimization algothrithm using orthogonal arrays is utilized for design in the discrete space. It is found that the method can remarkably decrease the number of function evaluations.