• 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.

• IE interfaces
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• v.23 no.2
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• pp.118-125
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• 2010

The determination of a regression model is important in using statistical designs of experiments. Generally, the exact regression model is not known, and experimenters suppose that a certain model form will be fit. Then an experimental design suitable for that predetermined model form is selected and the experiment is conducted. However, the initially chosen regression model may not be correct, and this can result in undesirable statistical properties. We develop model-robust experimental designs that have stable prediction variance for a family of candidate regression models over a cuboidal region by using genetic algorithms and the desirability function method. We then compare the stability of prediction variance of model-robust experimental designs with those of the 3-level face centered cube. These model-robust experimental designs have moderately high G-efficiencies for all candidate models that the experimenter may potentially wish to fit, and outperform the cuboidal design for the second-order model. The G-efficiencies are provided for the model-robust experimental designs and the face centered cube.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.10
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• pp.1455-1460
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• 2000

Chinese-style pork jerky with different levels (3, 6 and 9%) of glycerol or sorbitol were prepared. Moisture content, water activity ($a_w$) and shear value decreased with the addition of glycerol or sorbitol. During storage at $28^{\circ}C$ thiobarbituric acid (TBA) value of all samples declined with the addition of glycerol or sorbitol during storage time. After storage at room temperature ($28^{\circ}C$) for 180 days, the volatile basic nitrogen (VBN) of all treated products were less than the control group. In addition, the mold and yeast growth were inhibited slightly with the addition of glycerol or sorbitol. The absorption isotherm of pork jerky with different levels of glycerol at $25^{\circ}C$ had an aw above 0.75, and moisture contents at 6 and 9% which were higher than the control group. The moisture content was less than the control group with the addition of sorbitol. The chewiness desirability score of pork jerky with 6% glycerol was higher than the other treatments. However, no differences in hardness desirability score due to treatments were detected by sensory panelists.

• The Journal of Korean Association of Computer Education
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• v.10 no.1
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• pp.55-66
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• 2007

To improve access to the learning opportunities of students with disabilities, this study is to identify the potential of the information communication technology in education for the disabilities and to suggest the policy reforms for the special education technology. To answer it, the related literatures of other developed countries and Korea were collected and analyzed by desirability and feasibility as criteria. From the view of the desirability, this study found that the policies of special education in Korea were still regarded as subsidiary and separated from the general students. Moreover, from the view of the feasibility, the law and financial support was relatively insufficient than other countries to implement the policy more effectively and stably. To solve these problems, this study suggests the policy reforms in Korea as five areas and seven tasks.

• Korean Journal of Food Science and Technology
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• v.28 no.2
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• pp.298-304
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• 1996

Thirty-nine samples of roasted sesame seed oils were sensorially evaluated in terms of nutty odor, burnt odor and overall desirability, and their volatile compounds quantitatively analysed using direct sampling capillary GLC. Five volatile compounds were appeared to be significant for the sensory Properties of sesame oils through the multivariate analytical techniques such as stepwise discriminant analysis. canonical discriminant analysis, discriminant analysis and principal component analysis. The most important compounds were 2,5-dimethylpyrazine and 2-methylpyrazine which could be effectively used as chemical indicators related to nutty and burnt odor of sesame oils, respectively. The sesame oils which have represented a good grade of overall desirability have been always kept $35.82{\sim}4.43$ ppm of 2,5-dimethylpyrazine and also $28.90{\sim}6.35$ ppm of 2-methylpyrazine.

• Food Engineering Progress
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• v.21 no.3
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• pp.256-266
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• 2017

This study was designed to optimize ethanol extraction process of unfertilized corn silk (UCS) to maximize phytochemical contents and bioactivities. The response surface methodology (RSM) with central composite design (CCD) was employed to obtain the optimal extraction conditions. The influence of ethanol concentration, extraction temperature and extraction time on total polyphenol contents, total flavonoid contents, maysin contents, 2,2-diphenyl-1-picrylhydrazyl(DPPH) radical scavenging activities and tyrosinase inhibition were analyzed. For all dependable variables, the most significant factor was ethanol concentration followed by extraction temperature and extraction time. The following optimum conditions were determined by simultaneous optimization of several responses with the Derringer's desirability function using the numerical optimization function of the Design-Expert program: ethanol concentration 80.45%, extraction temperature $53.49^{\circ}C$, and extraction time 4.95 h. Under these conditions, the predicted values of total polyphenol contents, total flavonoid contents, maysin contents, DPPH radical scavenging activity and tyrosinase inhibition were $2758.74{\mu}g\;GAE/g$ dried sample, $1520.81{\mu}g\;QUE/g$ dried sample, 810.26 mg/100g dried sample, 56.86% and 43.49%, respectively, and the overall desirability (D) was 0.74.

• Computers and Concrete
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• v.23 no.6
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• pp.421-431
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• 2019

The alarming rate of depletion of natural stone based coarse aggregates is a cause of great concern. The coarse aggregates occupy nearly 60-70% by volume of concrete being produced. Research efforts are on to look for alternatives to stone based coarse aggregates from sustainability point of view. Response surface methodology (RSM) is adopted to study and address the effect of ferrochrome slag (FCS) replacement to coarse aggregate replacement in the ordinary Portland cement (OPC) based concretes. RSM involves three different factors (ground granulated blast furnace slag (GGBS) as binder, flyash (FA) as binder, and FCS as coarse aggregate), with three different levels (GGBS (0, 15, and 30%), FA (0, 15, and 30%) and FCS (0, 50, and 100%)). Experiments were carried out to measure the responses like, workability, density, and compressive strength of FCS based concretes. In order to optimize FCS replacement in the OPC based concretes, three different traditional optimization techniques were used (grey relational analysis (GRA), technique for order of preference by similarity (TOPSIS), and desirability function approach (DFA)). Traditional optimization techniques were accompanied with principal component analysis (PCA) to calculate the weightage of responses measured to arrive at the final ranking of replacement levels of GGBS, FA, and FCS in OPC based concretes. Hybrid combination of PCA-TOPSIS technique is found to be significant when compared to other techniques used. 30% GGBS and 50% FCS replacement in OPC based concrete was arrived at, to be optimal.

• Food Science of Animal Resources
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• v.43 no.5
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• pp.889-900
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• 2023

In this study, concentration levels of beet powder (BP) and caramel color (CC) were optimized to simulate beef color in meat analogs before and after cooking. The central composite design of response surface methodology (RSM) was used to set the levels of BP and CC, and the CIE L^*, CIE a^*, and CIE b^* were selected as the responses for RSM. After optimization, myoglobin-free beef patties were prepared with three optimized levels of BP and CC. When raw, all the patties had the same color as natural beef; however, CIE L^*, CIE a^*, and CIE b^* were statistically different from those of beef after cooking (p<0.05). Moreover, the use of BP and CC induced "browning" after the cooking process, with no excessive yellow color. Therefore, based on the overall desirability in the color optimization using RSM, the combination of BP (1.32%) and CC (1.08%) with the highest overall desirability can be used to simulate the color change of beef in meat analogs.

• Journal of Dairy Science and Biotechnology
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• v.41 no.2
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• pp.45-56
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• 2023

This review serves two purposes: first, to promote the use of improved optimization techniques in response surface methodology (RSM); and second, to enhance the optimum conditions for the fermentation of probiotics. According to research in dairy science, Lactiplantibacillus plantarum K79 is a candidate probiotic that has beneficial health effects, such as lowering blood pressure. The optimum conditions for L. plantarumK79 to produce peptides with angiotensin-converting enzyme (ACE) inhibitory activity were proposed, through modeling each of ACE inhibitory activity and pH as a function of the four factors that are skim milk concentration (%), incubation temperature (℃), incubation time (hours), and starter added amount (%). To estimate optimum conditions, the researchers employed a desirability-based multi-response optimization approach, utilizing third-order models with a nonsignificant lack of fit. The estimated optimum fermentation conditions for L. plantarum K79 were as follows: a skim milk concentration of 10.76%, an incubation temperature of 36.9℃, an incubation time of 23.76 hours, and a starter added amount of 0.098%. Under these conditions, the predicted ACE inhibitory activity was 91.047%, and the predicted pH was 4.6. These predicted values achieved the objectives of the multi-response optimization in this study.

• Korean journal of food and cookery science
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• v.16 no.3
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• pp.267-271
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• 2000

The present study was designed to develop the standardized formula for the preparation Jeung-Pyun with added raw soy flour and to investigate the applicability of Jeung-Pyun as the substitute of regular pizza crust made with wheat flour. The effect of adding raw soy flour at 3%, 5% level on fermentation time and viscosity of batters and texture and general desirability of Jeung-Pyun pizza were also studied. As the level of raw soy flour was increased the time required for 1 st and 2nd fermentation decreased and viscosity of batters increased significantly. Jeung-Pyun crust after steaming found to have appropriate texture and form for a substitute of wheat flour pizza crust. Texture parameters determined by QST showed that Jeung-Pyun crust with added raw soy flour had lower values in hardness, cohesiveness and gumminess without any significant difference. However, chewiness of 5% raw soy flour group was significantly lower than control group. Texture of Jeung-Pyun crust and general desirability of Jeung-Pyun pizza were determined by sensory evaluation. Textural parameters of Jeung-Pyun crust were evaluated on the basis of hardness, cohesiveness, adhesiveness, tenderness and wetness. As a result of sensory evaluation Jeung-Pyun crust made with 5% raw soy flour had significant lower values in hardness, cohesiveness, tenderness and wetness than the control. However, the textural parameters between control and 3 % raw soy flour group were not significantly different. Jeung-Pyun pizza with topping were evaluated by sensory panel. Jeung-Pyun pizza made with 3% raw soy flour received the highest score in apperance and general desirability without any significant difference. 5% raw soy flour group had significantly lower score in general desirability among 3 treatment groups. In conclusion, Jeung-Pyun crust made by traditional Jeung-Pyun preparation method will be a good alternative to replace wheat flour pizza crust. Adding raw soy flour at 3% level did not affect the quality of Jeung-Pyun crust and had an effect of promoting fermentation. Jeung-Pyun Pizza crust was expected to have tender texture and slower retrogradation rate than regular pizza crust with wheat flour.