• Journal of Korean Academy of Nursing
• /
• v.32 no.3
• /
• pp.373-383
• /
• 2002

This study was performed to develope a scale of gender role identity in Korean adults based on the Bem's theory of androgyny. Although there were several tools in Korea, they were revealed having some problems of cultural differences, translation biases, and methodological problems. Methods: A list of 78 items were developed using the existing tools and descriptions from 5 married couples. The items were the typical personality characteristics which were manifested by gender, male or female. And the list contained several items which were the socially desirable personality characteristics. which would be simply used as contextual items. Validity of the 78 items were screened by 18 expert panels with 4 point Likert scale, and 57 items were judged as highly valid from 70% of the experts, which were selected as preliminary items for the tool. Using the preliminary tool which was developed as a 4 point Likert scale, data were collected from 1,127 subjects for item analysis and factor analysis. 53 items were remained, because 4 items whose item-total correlation were lower than 0.2 were excluded by the result of item analysis. Factor analysis was done with the 53 items, and 49 items whose factor loadings were same and higher than 0.4 were remained. 3 factors were identified with eigen value 2.0, and these factors were named as masculinity, femininity, and social desirability. Results and Conclusion: KGRII(Korean Gender Role Identity Inventory) which contained 45 items was developed, with 15 items for 3 factors. The reliability of the tool was very high. Cronbach alpha of the tool was 0.929, and alpha of the subscales were ranged from 0.841 to 0.922.

• The Korean Journal of Food And Nutrition
• /
• v.30 no.2
• /
• pp.319-325
• /
• 2017

In this study, we optimized the coffee extraction conditions for instant coffee production in two stage percolators, which is the most common coffee extractor for instant coffee production. A central composite design was used to build mathematical model equations for response surface methodology (RSM). In these equations, the yield and overall acceptability of the coffee extracts were expressed as second-order functions of three factors, the feed water temperature, draw-off factor (DOF), and extraction time (cycle time). Based on the result of RSM, the optimum conditions were obtained with the use of desirability function approach (DFA) which find the best compromise area among multiple options. The optimum extraction conditions to maximize the yield and overall acceptability over 40% of yield were found with $163^{\circ}C$ of feed water temperature, 4.3 of DOF and 27 minutes of extraction time (cycle time). These results provide a basic data for the coffee extraction conditions for the competitive instant coffee in the industry.

• Knowledge Management Research
• /
• v.21 no.1
• /
• pp.27-40
• /
• 2020

Response surface methodology (RSM) empirically studies the relationship between a response variable and input variables in the product or process development phase. The ultimate goal of RSM is to find an optimal condition of the input variables that optimizes (maximizes or minimizes) the response variable. RSM can be seen as a knowledge management tool in terms of creating and utilizing data, information, and knowledge about a product production and service operations. In the field of product or process development, most real-world problems often involve a simultaneous consideration of multiple response variables. This is called a multiple response surface (MRS) problem. Various approaches have been proposed for MRS optimization, which can be classified into loss function approach, priority-based approach, desirability function approach, process capability approach, and probability-based approach. In particular, the loss function approach is divided into univariate and multivariate approaches at large. This paper focuses on the univariate approach. The univariate approach first obtains the mean square error (MSE) for individual response variables. Then, it aggregates the MSE's into a single objective function. It is common to employ the weighted sum or the Tchebycheff metric for aggregation. Finally, it finds an optimal condition of the input variables that minimizes the objective function. When aggregating, the relative weights on the MSE's should be taken into account. However, there are few studies on how to determine the weights systematically. In this study, we propose an interactive procedure to determine the weights through considering a decision maker's preference. The proposed method is illustrated by the 'colloidal gas aphrons' problem, which is a typical MRS problem. We also discuss the extension of the proposed method to the weighted MSE (WMSE).

• Korean Journal of Food Science and Technology
• /
• v.39 no.2
• /
• pp.194-199
• /
• 2007

This study investigated possible improvements in the sensory and physicochemical characteristics of jeungpyun by the addition of Pleurotus eryngii powder. The volume of the jeungpyun batter prepared with the 1% Pleurotus eryngii powder showed the highest degree of fermentation. As fermentation continued, pH and saccharinity dropped, and then saccharinity increased as more Pleurotus eryngii powder was added. As the Pleurotus eryngii powder ratio increased, the L-value decreased, but the a- and b-values increased. In the texture profile analysis, the 5% Pleurotus eryngii powder showed the highest adhesiveness and the lowest springiness. For the sensory test, the highest springiness and overall desirability were found in the jeungpyun with 1% Pleurotus eryngii powder. Overall, according to the results of these experiments, the 1% and 3% Pleurotus eryngii powders are though to be the optimal concentrations for obtaining improvements in quality.

• Journal of Environmental Science International
• /
• v.20 no.7
• /
• pp.907-917
• /
• 2011

This study investigated the application of experimental design methodology to optimization of conditions of air-plasma and oxygen-plasma oxidation of N, N-Dimethyl-4-nitrosoaniline (RNO). The reactions of RNO degradation were described as a function of the parameters of voltage ($X_1$), gas flow rate ($X_2$) and initial RNO concentration ($X_3$) and modeled by the use of the central composite design. In pre-test, RNO degradation of the oxygen-plasma was higher than that of the air-plasma though low voltage and gas flow rate. The application of response surface methodology (RSM) yielded the following regression equation, which is an empirical relationship between the RNO removal efficiency and test variables in a coded unit: RNO removal efficiency (%) = $86.06\;+\;5.00X_1\;+\;14.19X_2\;-\;8.08X_3\;+\;3.63X_1X_2\;-\;7.66X_2^2$ (air-plasma); RNO removal efficiency (%) = $88.06\;+\;4.18X_1\;+\;2.25X_2\;-\;4.91X_3\;+\;2.35X_1X_3\;+\;2.66X_1^2\;+\;1.72X_3^2$ (oxygen-plasma). In analysis of the main effect, air flow rate and initial RNO concentration were most important factor on RNO degradation in air-plasma and oxygen-plasma, respectively. Optimized conditions under specified range were obtained for the highest desirability at voltage 152.37 V, 135.49 V voltage and 5.79 L/min, 2.82 L/min gas flow rate and 25.65 mg/L, 34.94 mg/L initial RNO concentration for air-plasma and oxygen-plasma, respectively.

• Journal of Korean Library and Information Science Society
• /
• v.24
• /
• pp.107-161
• /
• 1996

This study aims at introducing 'ethnography' which is one of the most representative qualitative research methods into Library and Information Science research in Korea.. Ethnography, derived from anthropology, helps researchers to understand the whole and deep aspect of the research object. That is because the researcher puts himself into the life-world of the research object and observes it for a long time. Ethnography can be used as an alternative method to quantitative research methods. Until now, Library and Information Science research in Korea has used quantitative research methods in almost every case. From the 1980s so-called 'scientific methods' using hypotheses testing, have provided the major premise for research methodology in Library and Information Science of Korea. And the researchers have seen their research object(Korean Libraries) not in the native perspective but largely in the western(especially American) perspective. There is a need in Korea for more culturally relative research. So the desirability of introducing ethnography and other qualitative research methods into Library and Information Science research in Korea can be summarized as follows : I. Ethnography and other qualitative methods are needed for the researchers to overcome the limitation of quantitative methods which have formed the main methodological paradigm in Library and Information Science research in Korea. While those quantitative scientific methods can be a n.0, pplied to the social sciences, they are not adequate for the social sciences. It is because the research objects of the social sciences are human and social phenomena. II. It is needed that Library and Information Science research in Korea pay more attention to the speciality of Korean libraries. To do researches based on the viewpoint of cultural-relativism, researchers should consider the cultural context of Korean libraries. During the past years researchers in other social science fields in Korea, especially sociology and pedagogy, have gradually a n.0, pplied the methods of ethnography to their fields. These social scientists have attempted to escape from ethnocentrism, a problem which has greatly influenced past and present research methods. To get a holistic and in-depth understanding of Korean libraries on the present stage, and to solve their problems radically, it seems imperative that Library and Information Science research in Korea pay more attention to qualitative research methods such as ethnography.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.13 no.4
• /
• pp.1480-1487
• /
• 2012

Recently, the safety of the coal-mining tunnels has been improved greatly, but accidents occur continually. Most tunnel support failures occur because the fish plate part that connects the I-beams is unable to withstand ground pressure. In the case of XX coal mine, the arch part of tunnel support bends to the upper direction. In such a case, excessive horizontal load as well as vertical load acts on the tunnel support. Horizontal load is caused by the sudden loosing of underground rock mass or the leakage of underground water, so it is fairly complex to predict horizontal loading on a tunnel support. To predict the horizontal load on this component is defined as the problem that determines the horizontal load conditions in wedges of tunnel support. This is an optimization problem in which maximum bending stress and horizontal load are considered by an objective function and design variables, respectively. Therefore, in this study, design of experiments and optimization algorithm were applied to identify the horizontal load in tunnel support.

• Environmental Engineering Research
• /
• v.25 no.1
• /
• pp.114-122
• /
• 2020

This study was aimed at using the Central Composite Design (CCD) and Box-Behnken Design (BBD) to compare the efficiency and to elucidate the main interacting parameters in the upflow anaerobic sludge blanket (UASB) reactor, namely: Organic Loading Rate (OLR), Hydraulic Retention Times (HRT) and pH at a constant temperature of 35℃. Optimum HRT (15 h), OLR (3.5 kg.m^-3.d^-1) and pH (7) resulted in biogas production of 5,800 mL/d and COD removal of 80.8%. BBD produced a higher desirability efficiency of 94% as compared to the CCD which was 92%. The regression quadratic models developed with high R² values of 0.961 and 0.978 for both CCD and BBD, respectively, demonstrated that the interaction models could be used to pilot the design space. BBD model developed was more reliable with a higher prediction of biogas production (5,955.4 ± 225.3 mL/d) and COD removal (81.5 ± 1.014%), much close to the experimental results at a 95% confidence level. CCD model predictions was greater in terms of COD removal (82.6 ± 1.06% > 80.8%) and biogas production (4,636.31 mL/d ± 439.81 < 5,800 mL/d) which was less than the experimental results. Therefore, RSM can be adapted for optimizing various wastewater treatment processes.

• Journal of Korean Society for Quality Management
• /
• v.42 no.4
• /
• pp.757-768
• /
• 2014

Purpose: In this paper we present a case study of developing fast curing adhesives for insulation material of LNG carriers using an extreme vertices design with four mixture components. Three material properties are considered - shear strength, viscosity, and tensile strength. In the optimization experiment, we used hardness instead of tensile strength due to shortage of specimens. Methods: We employ four-factor extreme vertices design with 19 runs and desirability function approach for simultaneously optimizing three responses. After selecting optimal condition of the mixture components, we do confirmation experiments to verify the reproducibility of the optimal condition under manufacturing circumstance. Results: Simultaneous optimal condition for the three responses, that is, shear strength, viscosity, and harness is obtained. At the optimal condition, confirmation experiments are executed in manufacturing circumstance. The variation for the shear strength is not satisfactory, which is due to the variation of the humidity. Conclusion: At the optimal condition three material properties are satisfactory. To reduce the variability for the shear strength, robust design is needed.

• Culinary science and hospitality research
• /
• v.24 no.1
• /
• pp.140-150
• /
• 2018

In this study, effects of microground coffee on the quality characteristics and acceptability of instant coffee with probiotics were investigated. A central composite design with two factors (roasting degree and dose of microground coffee) was used and ranges of roasting degree and dose were 30~50 (L value) and 5~10% respectively. Aroma preference, sweetness intensity, bitterness intensity, acidity intensity, body intensity and overall acceptability were evaluated as sensory characteristics and quadratic regression models of all the properties were significant. Especially in aroma preference and overall acceptability, the higher roasting degree and dose of microground coffee, the more aroma preference and overall acceptability of the coffee increased. And this results accorded with the object of this study to increase aroma preference and overall acceptability by blending microground coffee with instant coffee. On the other hand, 129 of aroma compounds were detected in instant coffee with microground coffee but 2,5-dimethyl-pyrazine, ethyl-pyrazine and furfural were significant in quadratic regression models. The optimal conditions were predicted by response surface methodology and desirability function approach and the optimal conditions of roasting degree and dose of microground coffee were 30(L value), 8.4%(w/w) respectively to maximize 2 sensory characteristics (overall preference, aroma preference) and 3 aroma components (2,5-dimethyl-pyrazine, ethyl-pyrazine, furfural).