• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.16 no.7 s.112
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• pp.720-728
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• 2006

A robust damage assessment technique is presented such that the location and severity of damage in structures can be identified using measured modal data. In order to identify the damage efficiently, the concept of design of experiment using orthogonal array is used for screening the main effects of each parameter which corresponds to possible damage location in FE model. Then, Taguchi method, which has been widely used for robust design in industry, is applied to parameter updating in analytical FE model. The numerical simulations of a truss structure show that damages in structure can be located from updated parameters.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2000.04a
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• pp.270-276
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• 2000

Hard turning has the potential to replace grinding process and to achieve significant reduction in production time and cost. The main applications for hard turning is finishing process, namely grinding process. Therefore, it must be able to satisfy high surface integrity of the workpiece. This paper discusses surface quality in terms of residual stress and damaged layer with respect to cutting parameters in an intermittent hard turning. Damaged layer experiment is carried out orthogonal array. From that is based on the orthogonal array. From the response table, cutting parameters are analyzed from the view point of the damaged layer and residual stress. From this experimental results, even though in the intermittent hard turning, surface integrity turns out be good enough for replacing grinding process.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.11 no.4
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• pp.31-38
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• 2012

In this paper, we selected primary cutting parameters that influence on surface roughness of cut bottom surface in end-milling for SM25C material. Those are overhang, depth of cut, feed rate and spindle speed. And then performed orthogonal array experiment and ANOVA by Taguchi method to determine that improved level combination of cutting parameters for betterment of working efficiency and surface roughness one of quality characteristics. And we verified a advisability of prediction model by verification test about level combination. From the results, main cutting parameter influences on surface roughness is spindle speed and the next is feed rate.

• Journal of the Korea Safety Management & Science
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• v.2 no.3
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• pp.27-36
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• 2000

The Robust Design method uses a mathematical tool called orthogonal arrays to study a large number of decision variables with a small number of experiments. It also uses a new measure of quality, called signal-to-noise (S/N) ratio, to predict the quality from the customer's perspective. Thus, the most economical product and process design from both manufacturing and customers' viewpoints can be accomplished at the smallest, affordable development cost. Many companies, big and small, high-tech and low-tech, have found the Robust Design method valuable in making high-quality products available to customers at a low competitive price while still maintaining an acceptable profit margin. A study to analyze and solve problems of a biochemical process experiment has presented in this paper. We have taken Taguchi's parameter design approach, specifically orthogonal array, and determined the optimal levels of the selected variables through analysis of the experimental results using S/N ratio.

• Journal of the Korea Safety Management & Science
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• v.3 no.1
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• pp.117-125
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• 2001

Polyacetal resin is usually used to make molds, but it is difficult to achieve dimension accuracy during molding. Therefore it is usually necessary to cut the polyacetal resin after a molding process. Polyacetal resin is easily machining by standard machine tool. Acetal is also a thermal stable material which can be totted without coolant Another concern about the use of polyacetal resin is that it absorbs water easily, which also results in problems with dimension accuracy Therefore, in this study, the cutting resistance of water-absorbed polyacetal resin and its surface roughness after cutting in order to achieve the highest degree of accuracy in the cutting of polyacetal resin were investigated. Also, The Robust Design method uses a mathematical tool called orthogonal arrays to study a large number of decision variables with a small number of experiments. It also uses a new measure of quality, called signal-to-noise (S/N) ratio, to predict the quality from the customer's perspective. Thus, we have taken Taguchi's parameter design approach, specifically orthogonal array, and determined the optimal levels of the selected variables through analysis of the experimental results using S/N ratio.

• Journal of the military operations research society of Korea
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• v.27 no.1
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• pp.73-88
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• 2001

Designing high quality products and processes at a low cost is central technological and economic challenge to the engineer. The combination of engineering concepts and statistical implementations offered by Taguchi\`s off-line design technique has proven t be invaluable. By examining some deficiencies in designs from the Taguchi\`s highly fractional, orthogonal main effect plan based on orthogonal arrays, alternative method is proposed. The maximum resolution or the minimum aberration criterion is commonly used for selecting 2$^{n-m}$ fractional designs. We present new high resolution (low aberration) linear graphs to simplify the complexity of selecting designs with desirable statistical properties. The new linear graphs approach shows a substantial improvement over Taguchi\`s linear graphs and other related graphical methods for planning experiment. The new set of linear graphs will allow the experimenter to maintain the simple approach suggested by Taguchi while obtaining the best statistical properties of the resulting design such as minimum aberration as a by-product without dependency on complicated computational algorithm or additional statistical training.g.

• Proceedings of the KIEE Conference
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• summer
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• pp.1145-1147
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• 2004

This paper proposed a new control method for single-phase hybrid active power filter. The proposed algorithm can change single phase system into the orthogonal system which has two phases giving time-delay in regular single phas and making the imaginary second phase. It can make orthogonal system like as being used in $3{\phi}/2{\phi}$ transformation with two phases. It can do complex calculation which calculates intantaneous reactive power. Istead of existing method applying to intantaneous reactive power theory in fixed reference frame, this paper proposed the algorithm which has advantage over reducing harmonics using rotating reference frame. It verified the effectiveness the proposed method through simulation and experiment.

• International Journal of Naval Architecture and Ocean Engineering
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• v.12 no.1
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• pp.258-269
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• 2020

This paper proposes Snapping Shrimp Noise (SSN) detection and corrupted Orthogonal Frequency Division Multiplexing (OFDM) reconstruction methods to increase Bit Error Rate (BER) performance when OFDM transmitted signal is corrupted by impulsive SSNs in underwater acoustic communications. The proposed detection method utilizes multilayer wavelet packet decomposition for detecting impulsive and irregularly concentrated and SSN energy in specific frequency bands of SSN, and the proposed reconstruction scheme uses iterative decision directed-subcarrier reconstruction to recover corrupted OFDM signals using multiple carrier characteristics. Computer simulations were executed to show receiver operating characteristics curve for the detection performance and BER for the reconstruction. The practical ocean experiment of SAVEX 15 demonstrated that the proposed method exhibits a better detection performance compared with conventional detection method and improves BER by 250% and 1230% for uncoded and coded data, respectively, compared with the conventional reconstruction scheme.

• Archives of design research
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• v.16 no.3
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• pp.183-190
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• 2003

It is a fundamental pre-requisite to thoroughly analyse and understand the things which are being designed in the process of industrial design. However, it is not always easy to acquire appropriate data to meet all the requirements to finally design a functionally superior products. This paper proposes an industrial design model with heightened reliability using the orthogonal array tables, which are fairly handy to apply when there are many design criteria to be considered at the onset stage Especially, in this research, the basic purpose of the orthogonal arrays that they try to compact the range of experiments and to improve the effectiveness of the experiment results is answered under average industrial design processes. At the same time, non-quantitative data of design factors are quantitative by the concurrency in design and their mutual actions are examined. This method can help industrial designers in narrowing their design possiblities by depicting more valid data, thus producing quality product designs by deriving optimal control factors.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.10
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• pp.1273-1279
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• 2011

The variable-swash-plate compressor has recently been adopted as a vehicle compressor to improve fuel efficiency. The rotation torque in the variable-swash-plate compressor and the pressure-affected piston have a great influence on the swash-plate design and deformation. This paper suggests the optimal configuration design by using Chebyshev orthogonal polynomial and optimization techniques. The orthogonal array (OA) and analysis of variance (ANOVA) techniques and response surface optimization, are employed to determine the main effects and their optimal design variables. According to the optimal design, we confirm an effective design variable in swash plate and explain the optimal solution, the usefulness for satisfying the constraints of maximum stress and deformation.