• Journal of the Korean Society of Food Culture
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• v.23 no.6
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• pp.761-770
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• 2008

The purpose of this study was to determine the optimum amount of four ingredients (spirulina, sugar, lemon and orange) for the preparation of spirulina madeleine using response surface methodology. Spirulina was added at a level of 3.5-6.0 g, sugar powder, at 40-60 g, while lemon and orange peel were included at a level of 0-8 g. The optimum mixing rates of spirulina powder, sugar powder, lemon and orange were 3.5, 40, 0, and 8 g for overall quality and 3.52, 54.42, 0, and 8 g for maximum score of overall organoleptic quality, respectively.

• Structural Engineering and Mechanics
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• v.63 no.3
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• pp.303-315
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• 2017

This paper presents a review on getting a Weighted Multi-Objective Optimization (WMO) of Tuned Mass Damper (TMD) parameters based on Response Surface Methodology (RSM) coupled central composite design and Weighted Desirability Function (WDF) to attenuate the earthquake vibration of a jacket supported Offshore Wind Turbine (OWT). To optimize the parameters (stiffness and damping coefficient) of damper, the frequency ratio and damping ratio were considered as a design variable and the top displacement and frequency response were considered as objective functions. The optimization has been carried out under only El Centro earthquake results and after obtained the optimal parameters, more two earthquakes (California and Northridge) has been performed to investigate the performance of optimal damper. The obtained results also compared with the different conventional TMD's designed by Den Hartog's, Sadek et al.'s and Warburton's method. From the results, it was found that the optimal TMD based on RSM shows better response than the conventional damper. It is concluded that the proposed response model offers an efficient approach regarding the TMD optimization.

• Industrial Engineering and Management Systems
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• v.7 no.3
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• pp.197-203
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• 2008

Many quality engineering practitioners continue to have a considerable interest in implementing the concept of response surface methodology to real situations. Recently, dual response surface approach is extensively studied and recognized as a powerful tool for robust design. However, existing methods do not consider the information provided by customers and design engineers. In this regard, this article proposes a flexible optimization model that incorporates that information via desirability function modeling. The optimization scheme and its modeling flexibility are demonstrated through an illustrative example by comparing the proposed model with existing ones.

• Journal of the Korean Society for Precision Engineering
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• v.22 no.8 s.173
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• pp.100-107
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• 2005

The objective of the study is to improve the quality of wheel bearing hub by the rigid-plastic finite element analysis and the response surface methodology. The rigid-plastic finite element codes, AFDEX-2D and DEFORM-3D, were used to analyze the two-dimensional and three-dimensional forging processes, respectively. The response surface analysis is used to find the minimum underfill by the variation of design variables such as the height of billet after upsetting and punch angles of blocker dies. The metal flow of forged product shows good agreement with the results from 2D and 3D analysis. Also, the quality of the wheel bearing hub has been improved by the optimization of design variables and the machining time has been reduced by the machining allowance.

• Journal of Korean Institute of Industrial Engineers
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• v.43 no.3
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• pp.164-175
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• 2017

Dual response surface optimization (DRSO) attempts to optimize mean and variability of a process response variable using a response surface methodology. In general, mean and variability of the response variable are often in conflict. In such a case, the process engineer need to understand the tradeoffs between the mean and variability in order to obtain a satisfactory solution. Recently, a Posterior preference articulation approach to DRSO (P-DRSO) has been proposed. P-DRSO generates a number of non-dominated solutions and allows the process engineer to select the most preferred solution. By observing the non-dominated solutions, the DM can explore and better understand the trade-offs between the mean and variability. However, the non-dominated solutions generated by the existing P-DRSO is often incomprehensive and unevenly distributed which limits the practicability of the method. In this regard, we propose a modified P-DRSO using multiple objective genetic algorithms. The proposed method has an advantage in that it generates comprehensive and evenly distributed non-dominated solutions.

• Korean Journal of Food Science and Technology
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• v.28 no.2
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• pp.212-219
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• 1996

Four-dimensional response surface methodology was used for monitoring dynamic changes in substrates during Maillard reaction. The coefficients of determination ($R^2$) of response surface regression equations for the changes in amino acids during Maillard reaction were 0.9478 for total amino acids and above 0.90 for each amino acid. $R^2$ of regression equations for the changes in sugars during Maillard reaction were 0.9250 for glucose and 0.6490 for fructose. The contents of total amino acids gradually decreased with increasing reaction temperature and pH of the solvent. Browning color intensity increased with rising reaction temperature, showing maximum color intensity at around $145^{\circ}C$. Each amino acid showed a decreasing tendency in its contents, which was similarly found in total amino acids. Four-dimensional response surface methodology indicated that the increased temperature during Maillard reaction was the most influential factor in decreasing substrates, such as aspartic acid, threonine and glucose. While the reaction time and pH of solvent little affected the changes in the above-mentioned substrates during Maillard reaction.

• Journal of Life Science
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• v.13 no.6
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• pp.794-798
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• 2003

Batch production of (S)-phenyl oxirane was investigated using epoxide hydrolase activity of Rhodosporidium toruloides SJ-4. Effect of reaction condition of asymmetric biohydrolysis of racemic phenyl oxirane was analyzed and optimized by response surface methodology. The optimal conditions of pH, temperature and DMSO cosolvent ratio were 7.4, $34^P\circ}C$, and 2.3%(v/v), respectively. The final yield was enhanced up to 67%, and reaction times required to reach 99% ee (enatiomeric excess) decreased down to 50% by response surface methodology Enantiopure (S)-phenyl oxirane with 100% enantiopurity and 24% yield (theoretical yield = 50%) was obtained from racemic substrate.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.23 no.3
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• pp.284-290
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• 2014

Aluminum alloy is a core material for structural parts of aircraft and automobiles to reduce the weight and maintain high specific strength. This study evaluates the machinability and investigates the optimal cutting conditions considering the surface integrity and productivity for Al7050-T7451 milling. The machining variables considered are the feed per tooth, spindle speed, axial depth of the cut, and radial depth of the cut. The machinability evaluation of Al7050-T7451 is conducted by analyzing the cutting force signals, acceleration signals, AE signals, and machined surface conditions. The optimal cutting conditions are determined by analyzing the experimental results using response surface methodology for stable machining considering the productivity and surface integrity.

• Journal of Microbiology and Biotechnology
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• v.20 no.4
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• pp.835-843
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• 2010

The objectives of this study were to investigate the effect of fermentation medium on the hydroxyl radical scavenging activity of exopolysaccharides from Inonotus obliquus by response surface methodology (RSM). A two-level fractional factorial design was used to evaluate the effect of different components of the medium. Corn flour, peptone, and $KH_2PO_4$ were important factors significantly affecting hydroxyl radical scavenging activity. These selected variables were subsequently optimized using path of steepest ascent (descent), a central composite design, and response surface analysis. The optimal medium composition was (% w/v): corn flour 5.30, peptone 0.32, $KH_2PO_4$ 0.26, $MgSO_4$ 0.02, and $CaCl_2$ 0.01. Under the optimal condition, the hydroxyl radical scavenging rate (49.4%) was much higher than that using either basal fermentation medium (10.2%) and single variable optimization of fermentation medium (35.5%). The main monosaccharides components of the RSM optimized polysaccharides are rhamnose, arabinose, xylose, mannose, glucose, and galactose with molar proportion at 1.45%, 3.63%, 2.17%, 15.94%, 50.00%, and 26.81%.

• Journal of Microbiology and Biotechnology
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• v.20 no.11
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• pp.1597-1602
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• 2010

Chitinase is one of the most important mycolytic enzymes with industrial significance. This enzyme is produced by a number of organisms including bacteria. In this study, we describe the optimization of media components with increased production of chitinase for the selected bacteria, Stenotrophomonas maltophilia, isolated from soil. Different components of the defined media responsible for influencing chitinase secretion by the bacterial isolate were screened using Plackett-Burman experimental design and were further optimized by Box-Behnken factorial design of response surface methodology in liquid culture. Maximum chitinase production was predicted in medium containing 4.94 g/l chitin, 5.56 g/l maltose, 0.62 g/l yeast extract, 1.33 g/l $KH_2PO_4$, and 0.65 g/l $MgSO_4{\cdot}7H_2O$ using response surface plots and the point prediction tool of the DESIGN EXPERT 7.1.6 (Stat-Ease, USA) software.