• Journal of Microbiology and Biotechnology
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• v.12 no.3
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• pp.490-496
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• 2002

The production of E. coli WC7 phytase from a recombinant E. coli strain was optimized using a statistical experimental design approach. Two-level complete factorial designs with seven variables were used for the media optimization. In the first optimization step, the influence of disodium succinate, yeast extract, $K_2HPO_4,\;NH_4H_2PO_4,\;MgSO_4$, NaCl, and trace elements on phytase production was evaluated. As a result, disodium succinate, yeast extract, $NH_4H_2PO_4$, NaCl, and the trace elements were found to have a positive influence on the phytase production, while $K_2HPO_4\;and\;MgSO_4$ had a negative influence. In the second step, the concentrations of disodium succinate and yeast extract were further optimized using central composite designs. The maximum phytase activity obtained was 234 U/ml using 15.9 g/1 disodium succinate, 20 g/1 yeast extract, 5 g/1 K_2HPO_4,\;10 g/1 NH_4H_2PO_4,\;1.5 g/1 MgSO_4$, 4 g/1 NaCl, and 1.5 m1/1 trace elements, which was about a 14-fold increase in comparison with that obtained using the basal medium.

• Journal of Microbiology and Biotechnology
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• v.16 no.9
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• pp.1410-1415
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• 2006

Media components, including date juice, sodium acetate, peptone, and $K_{2}HPO_4$, which were screened by Plackett-Burman fractional factorial design, were optimized for lactic acid production from date juice using the response surface method (RSM). Sodium acetate, peptone (p<0.0001), and $K_{2}HPO_4$ (p=0.0029) were highly significant in influencing the lactic acid production. Close correlationship between predicted and experimental values was observed. When the optimum values of the parameters obtained through RSM (25.0 g/l date sugar, 15.0 g/l sodium acetate, 19.1 g/l peptone, and 4.7 g/l $K_{2}HPO_4$) were applied, lactic acid production (22.7 g/l) increased by 50.33%, compared with unoptimized media (15.1 g/l). The subsequent validation experiments confirmed the validity of the statistical model.

• Preventive Nutrition and Food Science
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• v.22 no.1
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• pp.37-44
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• 2017

Sulfur-containing amino acids play important roles in good flavor generation in Maillard reaction of non-enzymatic browning, so aqueous model systems of glucosamine and cysteine were studied to investigate the effects of reaction temperature, initial pH, reaction time, and concentration ratio of glucosamine and cysteine. Response surface methodology was applied to optimize the independent reaction parameters of cysteine and glucosamine in Maillard reaction. Box-Behnken factorial design was used with 30 runs of 16 factorial levels, 8 axial levels and 6 central levels. The degree of Maillard reaction was determined by reading absorption at 425 nm in a spectrophotometer and Hunter's L, a, and b values. ${\Delta}E$ was consequently set as the fifth response factor. In the statistical analyses, determination coefficients ($R^2$) for their absorbance, Hunter's L, a, b values, and ${\Delta}E$ were 0.94, 0.79, 0.73, 0.96, and 0.79, respectively, showing that the absorbance and Hunter's b value were good dependent variables for this model system. The optimum processing parameters were determined to yield glucosamine-cysteine Maillard reaction product with higher absorbance and higher colour change. The optimum estimated absorbance was achieved at the condition of initial pH 8.0, $111^{\circ}C$ reaction temperature, 2.47 h reaction time, and 1.30 concentration ratio. The optimum condition for colour change measured by Hunter's b value was 2.41 h reaction time, $114^{\circ}C$ reaction temperature, initial pH 8.3, and 1.26 concentration ratio. These results can provide the basic information for Maillard reaction of aqueous model system between glucosamine and cysteine.

• Journal of the Korean Society of Clothing and Textiles
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• v.30 no.7 s.155
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• pp.1034-1043
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• 2006

The purpose of this study was to investigate the difference of the visual evaluation about gathered skirts according to different gathering conditions and objects. The experiment is made of factorial design for three variables-fabric(cotton, wool, polyester), ratio of gathers(1.5T, 2.0T, 2.5T), objects(real thing, 2D digital picture, 3D shape). Questionnaire consists of 33 sematic differential scale expressing gathered skirts' image. The subjects were 50 male and female students majoring in clothing and textile. The data were analyzed by Frequency, Factor analysis, Anova, scheffe's test. The results obtained were summarized as follows; 1. As the open-ended response there were difference among the image according to different gathering conditions and obects. 2. The image of gathered skirts was composed of 6 factors; activities, attraction, attention, softness, moderateness, function. 3. For visual evaluation of gathering conditions as different objects, there were similar as softly in fabrics and lager in ratio of gathers. 4. For visual evaluation of different objects as gathering conditions, there was more difference effect of ratio of gathers than fabrics.

• Transactions on Control, Automation and Systems Engineering
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• v.2 no.4
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• pp.268-273
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• 2000

Plasma models are crucial to equipment design and process optimization. A radial basis function network(RBFN) in con-junction with statistical experimental design has been used to model a process plasma. A 2$^4$ full factorial experiment was employed to characterized a hemispherical inductively coupled plasma(HICP) in characterizing HICP, the factors that were varied in the design include source power, pressure, position of shuck holder, and Cl$_2$ flow rate. Using a Langmuir probe, plasma attributes were collected, which include typical electron density, electron temperature. and plasma potential as well as their spatial uniformity. Root mean-squared prediction errors of RBEN are 0.409(10(sup)12/㎤), 0.277(eV), and 0.699(V), for electron density, electron temperature, and Plasma potential, respectively. For spatial uniformity data, they are 2.623(10(sup)12/㎤), 5.704(eV) and 3.481(V), for electron density, electron temperature, and plasma potential, respectively. Comparisons with generalized regression neural network(GRNN) revealed an improved prediction accuracy of RBFN as well as a comparable performance between GRNN and statistical response surface model. Both RBEN and GRNN, however, experienced difficulties in generalizing training data with smaller standard deviation.

• Journal of the Korean Society of Clothing and Textiles
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• v.33 no.2
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• pp.331-342
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• 2009

The purposes of this study were to provide the apparel companies with a effective marketing strategy by identifying the present condition of loyalty programs and designing the type of reward and the timing of reward, and to investigate the effects of loyalty programs on customers' satisfaction and loyalty. The experimental study was conducted to examine the relationship between loyalty programs and performances. The experiment, which adopted a scenario methodology, was a 2(type of rewards)${\times}$2(timing of rewards) between subjects factorial design. The sample was based on 362 college students. The data analysis was completed on the basis of SPSS 12.0 package, using descriptive analysis, frequency, factor analysis, Cronbach's a, ANOVA, and regression analysis. The following results were found in this research. First the respondent's recognition of reward(benefit, reserve fund, experience) was not relatively high. Second, the interaction effect of type of rewards and timing of rewards on the loyalty programs' satisfaction(p<.01) and customer loyalty(p<.001) was significant, but that on customer satisfaction was not significant. Finally, loyalty programs' satisfaction positively affected customer satisfaction and loyalty. The implications of the research and directions for future researchers were discussed.

• Journal of Distribution Science
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• v.21 no.6
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• pp.1-11
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• 2023

Purpose: As a modern distribution channel, the growth of e-commerce has brought more competitive pressures on e-marketplace, making trust and loyalty become top priority. As one of many sources of trust and loyalty issues, understanding the effect of careless marketing communications on consumers' perception is critical. This study examines the effect of careless marketing communications (e.g. misspellings, incomplete information) in website on consumers' trust toward and confidence in purchasing a product from an e-commerce. Research design and methodology: An experimental research design (with two experimental studies) was used in to test the hypotheses. Study 1 employs a single-factor design and study 2 employs a 2x2, full-factorial, between-subjects design. Results: Results of the two experimental studies (Study 1, n = 60; Study 2, n = 140) demonstrate that simple mistakes significantly decrease consumers' trust toward an e-commerce and their confidence to purchase from the e-commerce. The effect is found to be significant in the case of high-involvement products; whereas no effect is found in low-involvement products. Conclusions: E-commerce relies heavily on carefully crafted marketing communications to establish consumers' trust and confidence. These studies confirm the equal importance of distribution and communication in maintaining consumers' trust and sustainability of the business.

• International Journal of Human Ecology
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• v.11 no.1
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• pp.1-10
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• 2010

Two elements of paisley textile design (color and size of motif) were manipulated to investigate their effects on people's perception. Korean and Caucasian American women were selected to represent Asian and Western countries to compare the differences in image perceptions of paisley patterns between two cultures. The participants were 168 female university students composed of 84 Caucasian Americans and 84 Koreans. The experimental design was a $2{\times}2{\times}7$ factorial design: two levels of perceiver's culture, two levels of motif size, and seven levels of the motif color. The four factors used to account for image perception were an elegance factor, individuality factor, maturity factor, and femininity factor. The results of the present study confirm that image perception can be different according to the color and size of a motif and the perceiver's culture. In the results, Americans perceived the paisley pattern as more preferable than Koreans did. Red background + Orange motif was perceived as the most feminine and Dark blue background + Sky blue motif and Dark gray background + Gray motif was perceived as the most masculine in both cultures. Compared to the big motif, the small motif was perceived as more elegant in both cultures.

• Journal of the Korean Society of Costume
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• v.59 no.5
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• pp.167-179
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• 2009

The purposes of this study were to explore the influence on fashion brand image and brand loyalty according to fit of the fashion brand with cultural art field, motivation in culture marketing of the apparel company, and involvement of the consumers in art activities. The subjects ware 274 male and female in 20s and 30s living in Seoul and Gyeonggi area. The study was obtained through the use of an experimental design which was $2{\times}[2{\times}2]$ mixed factorial design. The summary main results were as follows. First, as far as the effect of the three variables on the social contribution image of the fashion brand, the results of the 3-way interaction are positive. Second, as far as the effect of the three variables on the product image of the fashion brand, the data suggests that only the main-effect of motivation in culture marketing of the apparel company is meaningfully positive. Third, as far as the effect of the three variables on fashion brand loyalty, both fit of the fashion brand with cultural art field and involvement of the consumers in art activities variables show positive results.

• Journal of the Korean Society of Costume
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• v.66 no.8
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• pp.1-13
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• 2016

The purpose of this study was to analyze the effects of comparative advertisement brand typicality and need for recognition in outdoor apparel market. This study was created with a mixed factorial design of 2 (Advertisement types: Comparative advertisement vs. General advertisement) X 2(Brand Typicality: High Brand vs. Low Brand) X 2 (Need for Cognition: High vs. Low). The results of this study are as follows: First, it was shown that comparative advertisement had a greater positive influence on attitudes toward advertising intentions in comparison to general advertisements. Second, while comparative advertisement was more effective than general advertisement for outdoor apparel brands with low typicality. Third, consumers with higher need for cognition showed a preferred attitude toward advertising intention when met with comparative advertising in contrast to general advertisement. Fourth, when consumers with higher needs for cognition were exposed to advertisement for brands of lower typicality, there was higher positive influence on the attitudes toward advertisement intention with comparative advertisement in comparison to general advertisement. This means the comparative advertisement may be effective for the new garment brand or the garment brands having low typicality to secure the cognition quickly from the consumers having high need for cognition.