• Applied Chemistry for Engineering
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• v.31 no.2
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• pp.147-152
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• 2020

In this study, we dedicated to optimize the process for a reactive diluent for epoxy resin of improved chemical resistance by using cardanol, a component of natural oil of cashew nut shell liquid (CNSL). The central composite design (CCD) model of response surface methodology (RSM) was used for the optimization. The quantitative factors for CCD-RSM were the cardanol/ECH mole ratio, reaction time, and reaction temperature. The yield, epoxy equivalent, and viscosity were selected as response values. Basic experiments were performed to design the reaction surface analysis. The ranges of quantitative factors were determined as 2~4, 4~8 h, and 100~140 ℃ for the cardanol/ECH reaction mole ratio, reaction time, and reaction temperature, respectively. From the result of CCD-RSM, the optimum conditions were determined as 3.33, 6.18 h, and 120 ℃ for the cardanol/ECH reaction mole ratio, reaction time, and reaction temperature, respectively. At these conditions, the yield, epoxy equivalence, and viscosity were estimated as 100%, 429.89 g/eq., and 41.65 cP, respectively. In addition, the experimental results show that the error rate was less than 0.3%, demonstrating the validity of optimization.

• Korean Journal of Food Science and Technology
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• v.43 no.6
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• pp.689-695
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• 2011

1,3-Dioleoyl-2-palmitoylglycerol (OPO)-rich human milk fat substitute (HMFS) was synthesized from tripalmitin (PPP)-rich fraction and oleic ethyl ester by a lipase-catalyzed interesterification. Response surface methodology (RSM) was employed to optimize the presence of palmitic acid at sn-2 position ($Y_1$, %) and of oleic acid at sn-1,3 ($Y_2$, %), with the reaction factors as substrate molar ratio of PPP-rich fraction to oleic ethyl ester ($X_1$, 1:4, 1:5 and 1:6), reaction temperature ($X_2$, 50, 55 and $60^{\circ}C$), and time ($X_3$, 3, 7.5 and 12 h). The optimal conditions for HMFS synthesis were predicted at the reaction combination of $55^{\circ}C$, 3 h and 1:6 substrate ratio. HMFS re-synthesized under the same conditions displayed 70.70% palmitic acid at the sn-2 position and 69.58% oleic acid at the sn-1,3 position. Reaction product was predominantly (90.35%) triacylglycerol (TAG) was observed in which the major TAG species, OPO, comprised 31.24%.

• Journal of Appropriate Technology
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• v.5 no.2
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• pp.82-90
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• 2019

The Box-Benhken Design (BBD) model of response surface methodology (RSM) was used to optimize fluoride adsorption conditions in water using a 350℃ thermally treated cow bone. Water temperature, pH, contact time, and initial fluoride concentration were selected as variables to be optimized. A second order reaction equation was obtained from a Box-Behnken Design DoE experimental matrix of 29 runs. R² and p-value of the model were 0.9242 and <0.0001, respectively, indicating that the selected variables had a very substantial effect on the adsorption results. The optimized adsorption capacity of the thermally synthesized bone char was estimated to be 6.46 mgF/g at the water temperature of 39.68℃, pH 6.25, contact time of 88.81 minutes and an initial fluorine concentration of 14.64 mgF/L.

• Applied Chemistry for Engineering
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• v.28 no.3
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• pp.286-289
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• 2017

Synthesis of zeolite 4A was carried out to optimize the nanoparticle synthesis process using statistical experimental design method. The zeolite 4A was synthesized by controlling the concentration of the silicon precursor, sodium metasilicate (SMS), and characterized by XRD, SEM and nitrogen adsorption. In particular, the property of zeolite 4A can be determined by XRD analysis. Using the general factor analysis in the design of experiments, we analyzed main effects and interactions according to the reactor, reaction temperature and reaction time. The optimum reaction condition for the synthesis of zeolite 4A crystallinity was using an autoclave for 3 hours at $110^{\circ}C$. Furthermore, the optimal synthesis conditions of zeolite 4A with various crystallinity using Ludox as a silicon precursor were presented of what using both the surface and contour plot.

• Journal of Life Science
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• v.27 no.1
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• pp.38-43
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• 2017

Glycosyl aesculin, a potent anti-inflammatory agent, was synthesized by transglycosylation reaction, catalyzed by Thermotoga neapolitana ${\beta}-glucosidase$, with aesculin as an acceptor. The key reaction parameters were optimized using response-surface methodology (RSM) and $2{\mu}g$ of the enzyme. As shown by a statistical analysis, a second-order polynomial model fitted well to the data (p<0.05). The response surface curve for the interaction between aesculin and other parameters revealed that the aesculin concentration and reaction time were the primary factors that affected the yield of glycosyl aesculin. Among the tested factors, the optimum values for glycosyl aesculin production were as follows: aesculin concentration of 9.5 g/l, temperature of $84^{\circ}C$, reaction time of 81 min, and pH of 8.2. Under these conditions, 61.7% of glycosyl aesculin was obtained, with a predicted yield of 5.86 g/l. The maximum amount of glycosyl aesculin was 6.02 g/l. Good agreement between the predicted and experimental results confirmed the validity of the RSM. The optimization of reaction conditions by RSM resulted in a 1.6-fold increase in the production of glycosyl aesculin as compared to the yield before optimization. These results indicate that RSM can be effectively used for process optimization in the synthesis of a variety of biologically active glycosides using bacterial glycosidases.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 1997.04a
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• pp.215-220
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• 1997

본 연구는 추진제 연소관 내부에 도포 되는 내열재 라이닝 공정을 최적화하기 위해 라이너 Premix 반응성을 실험하고 그결과를 토대로 Premix 저장조건을 설정하였다. HX-계열의 Bonding agent를 사용하는 LH-2, LH-5, LH-6 라이너를 선택하여 각각 20, 30, $40^{\circ}C$하에서 5주간 저장후 경화제와 경화촉매를 주입하고 초기점도를 측정하여 반응성을 예측하였다. 그 결과 Bonding agent로 HX-868을 사용하는 LH-5, LH-6 라이너가 HX-752를 사용하는 LH-2보다 반응성이 빠르며, 경화제와 경화촉매로 DDI와 T-12를 사용하는 LH-5 라이너가 IPDI와 $Fe(AA)_3$를 사용하는 LH-6 라이너 보다 반응성이 빠르게 나타났다. 이러한 저장온도와 기간에 따른 반응성을 토대로 공정 적용시 급격한 점도 상승에 의한 작업의 불안정성을 피하기 위해 일정 점도를 초과하지 않는 라이너 Premix 저장조건을 설정하였고, 향후에는 Bonding agent로. HX-868을 사용하는 LH-5, LH-6 라이너는 보다 공정성이 양호한 HX-752로 바꾸어 주는 것이 바람직 할 것이다.

• KSBB Journal
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• v.17 no.2
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• pp.195-202
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• 2002

The production conditions of cellulolytic enzymes by a fungus, strain FJ1, were optimized using response surface analysis. The culture factors which largely affected the production of enzymes such as cultivation time, carbon source concentration, nitrogen source concentration, and composition ratio of carbon sources were employed. Optimizedconditions of the factors above corresponding to each cellulolytic enzyme production were as fellowing: CMCase production was obtained in the conditions of cultivation time of 5.4 days, carbon source concentration of 3.5%, nitrogen source concentration of 0.6%, and composition ratio of carbon sources of 52:48 (avicel:CMC), xylanase appeared in the conditions of 5.3 days, 3.5%, 0.8%, and 54:46, respectively, and $\beta$-glucosidase were 7.0 days, 5.0%, 1.0%, and 83:17, respectively, and avicelase were 6.5 days, 4.0%, 0.9%, and 64:36, respectively. The activities of CMCase, xylanase, p-glucosidase, and avicelase predicted by the response surface methodology were 33.5, 52.6, 2.88, and 1.84 U/mL, respectively, and $\beta$-glucosidase activity was enhanced up to 74% when compared to that obtained in the experimental conditions.

• Food Engineering Progress
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• v.15 no.2
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• pp.97-115
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• 2011

A review about the application of response surface methodology in the optimization of food technology is presented. The theoretical principles of response surface methodology and steps for its application are described. The response surface methodologies : three-level full factorial, central composite, Box-Behnken, and Doehlert designs are compared in terms of characteristics and efficiency. Furthermore, recent references of their uses in food technology are presented. A comparison between the response surface designs (three-level full factorial, central composite, Box-Behnken and Doehlert design) has demonstrated that the Box-Behnken and Doehlert designs are slightly more efficient than the central composite design but much more efficient than the three-level full factorial designs.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.2
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• pp.625-633
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• 2013

Multiple response surface optimization (MRSO) aims at finding a setting of input variables which simultaneously optimizes multiple responses. The minimization of mean squared error (MSE), which consists of the squared bias and variance terms, is an effective way to consider the location and dispersion effects of the responses in MRSO. This approach basically assumes that both the terms have an equal weight. However, they need to be weighted differently depending on a problem situation, for example, in case that they are not of the same importance. This paper proposes to use the weighted MSE (WMSE) criterion instead of the MSE criterion in MRSO to consider an unequal weight situation.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.1
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• pp.97-105
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• 2015

Multiresponse optimization (MRO) seeks to find the setting of input variables, which optimizes the multiple responses simultaneously. The approach of weighted mean squared error (WMSE) minimization for MRO imposes a different weight on the squared bias and variance, which are the two components of the mean squared error (MSE). To date, a weighted sum-based method has been proposed for WMSE minimization. On the other hand, this method has a limitation in that it cannot find the most preferred solution located in a nonconvex region in objective function space. This paper proposes a Tchebycheff metric-based method to overcome the limitations of the weighted sum-based method.