• Journal of Korean Society on Water Environment
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• v.35 no.1
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• pp.55-63
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• 2019

The Four Major Rivers Restoration Project started in 2009 and completed in early 2013 is a large-scale inter-ministry SOC project investing ₩22.2 $10^{12}$ and one of the Project's objectives was to enhance the water-quality grade through recovering the river eco-system and environment. The average concentration and probability distribution of water-quality constituents at given and selected sampling sites are very significant elements for analyzing and controlling the water-quality of rivers or reservoirs effectively. Average concentration can be estimated by point estimator, distribution function of water-quality constituents or Bootstrap method, in which the distribution function estimated with more data in case of insufficient dataset, is applied. Ipo and Gangcheon water-quality monitoring stations in South Han River were selected to compare and analyze the variation of concentration before and after Ipo and Gangcheon Weirs construction, using the whole 4-year's data, from 2005 to 2008 and from 2014 to 2017. Water-quality constituents such as BOD and COD relating to oxygen demanding wastes and TP and Chlorophyll-a relating to the process of nutrient enrichment called eutrophication were also selected. The guidelines for water-quality control and management after weir construction including evaluation of water-quality constituents' variations can be presented by this paper.

• Korean Journal of Health Education and Promotion
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• v.32 no.2
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• pp.53-63
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• 2015

Objectives: The purpose of this study was to investigate association of depressive symptom, fatalism with selected health behaviors among people aged 50-69 with no physical limitation in Seoul. Methods: In 2012, data were collected using a household based interview survey in Seoul. One person in each selected household aged between 50 and 69 was selected and responded. Data analysis was based on 1,190 subjects who answered they do not have any physical activity limitation. Results: Multiple logistic regression analysis showed significant association among variables including perceived health, depressive symptom and fatalism scores on some health behaviors. Multiple regression analysis showed that selected health risk behaviors(current smoking, monthly alcohol consumption, no regular health exam in two years) were significantly associated with depressive symptom and fatality scores in addition to demographic variables. The final regression model's adjusted R square was about 0.235. Conclusion: Demographic variables such as gender, age and socioeconomic status were significant variables in health behaviors and these behavioral factors were associated with perceived health, depressive symptom and fatalistic views. As a conclusion, depressive symptom and fatalism should be monitored and intervened in health education practice.

• Korean Journal of Child Studies
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• v.31 no.1
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• pp.101-111
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• 2010

The purpose of this study was to develop a scale to measure the life satisfaction of after-school classes. For this purpose, utilizing the theoretical background and the findings of previous studies, 147 questions from eight factors were selected for the 1st draft and 67 questions were selected for the 2nd draft by reviewing the validity of the contents after consulting with eleven professionals. A preparatory survey and factor analysis was then conducted using 291 people and a total of 32 questions were extracted from four sub-factors. Exploratory factor analysis by principal component analysis was conducted and orthogonal rotation was conducted by means of the VARIMAX method. The reliability of the class environment, operation management, program and teacher relationship sector were found to be very high. It is suggested that this study can be of great benefit in developing a child-centered scale and it's reliability was also found to be high.

• Journal of the military operations research society of Korea
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• v.28 no.1
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• pp.83-96
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• 2002

The Analytic Hierarchy Process (AHP) is well suited to group decision making and offers numerous benefits as a synthesizing mechanism in group decisions. To date, the majority of AHP applications have been in group settings. One reason for this may be that groups often have an advantage over individual when there exists a significant difference between the importance of quality in the decision and the importance of time in which to obtain the decision. Another reason may be the best alternative is selected by comparing alternative solutions, testing against selected criteria, a task ideally suited for AHP. In general, aggregation methods employed in group AHP can be largely classified into two methods: geometric mean method and (weighted) arithmetic mean method. In a situation where there do not exist clear guidelines for selection between them, two methods do not always guarantee the same group decision result. We propose a simulation approach for building group consensus without efforts to make point estimates from individual diverse preference judgments, displaying possible disagreements as is natural in group members'different viewpoints.

• International Journal of Computer Science & Network Security
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• v.21 no.12spc
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• pp.451-458
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• 2021

Providing a secure and effective way to protect confidential and private data is an urgent process, and accordingly, we will present in this research paper a new method, which is called multiple rounds variable block method (MRVB) which depends on the use of a colored image that is kept secret to generate needed work and round keys. This method can be used to encrypt-decrypt data using various lengths private key and data blocks with various sizes. The number of rounds also will be variable starting from one round. MRVB will be implemented and compared with the encryption-decryption standards DES and AES to show the improvements provided by the proposed method in increasing the security level and in increasing the throughput of the process of data cryptography. The generated private key contents will depend on the used image_key and on the selected number of rounds and the selected number of bytes in each block of data.

• Journal of Physiology & Pathology in Korean Medicine
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• v.26 no.1
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• pp.35-39
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• 2012

Sweet potato soju(SPS) has been made by vacuum distillation because sweet potato contains much fibrous materials which give high density to sweet potato mash. Generally, the SPS made by vacuum distillation has soft flavors and tastes. If the viscosity of sweet potato mash could be decreased by degradation enzyme, the process and production of SPS making by the method of vacuum distillation may be simplified and easier to distil the fermented sweet potato. Because the fibrous materials of sweet potato contains pectin with methoxyl group, methanol can be produced by fibrous degradation enzyme. For appling the fiber degradation enzymes to sweet potato mash for making SPS, the enzyme should be needed to degrade fibrous material without producing methanol. Special two fibrolytic enzymes are selected from 26 kind of commercial enzymes for the simplified and easier production of sweet potato soju by vacuum distillation, The selected enzyme A and X can degrade the fibrous material pectin of sweet potato without producing methanol. Although the different companies have produced the enzymes, same cellulase has been prepared from Trichoderma. reesei. The viscosity of sweet potato mash treated by the enzymes is decreased by 3 times with comparison to the viscosity of sweet potato mash of control group. The methanol concentration in the vacuum distilled SPS treated with the enzymes is 0.16%. The concentration is similar to that of commercially distilled SPS(0.15%). The result may suggest that the selected cellulases, A and X, can be used to make SPS by vacuum distillation.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2004.10a
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• pp.382-387
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• 2004

As the increasing needs in the industrial filed, many studies for the 3D CAD system are carried out. There are two types of 3D CAD system. One is manifold modeler, the other is non-manifold modeler. In the manifold modeler only 3D objects can be modeled. In the non-manifold modeler 3D, 2D, 1D, and 0D objects can be modeled in a unified data structure. Recently there are many studies on the non-manifold modeler. Most of them are focused on finding unknown topological entities and representing all kinds of topological entities found. In this paper, efficient data structure is selected. The boundary information on a face and an edge is included in this data structure. The boundary information on a vertex is excluded considering the frequency of usage. Because the disk cycle information is not required in most case of modeling. It is compact. It stores essential non-manifold information such as loop cycle and radial cycle. A suitable Euler-Poincare equation is studied and selected. Using the efficient data structure and the selected Euler-Poincare equation, 18 basic Euler operators are implemented. Several 3D models are created using the implemented modeler. A non-manifold modeling can be carried out using the implemented 3D CAD system. The results of this paper could be used in the further studies such as an implementation of Boolean operators, and a translation of 2D CAD drawings to 3D models.

• Journal of the Korean Society of Food Culture
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• v.34 no.2
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• pp.184-200
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• 2019

This study aims to establish a strategy for selling kimchi to satisfy the needs and wants of European consumers through survey, FGI, and IDI. All survey participants were Europeans and were selected on the basis of their kimchi awareness. For the quantitative survey, 246 participants 15 years or older were selected; for FGI, 33 participants aged between 20 and 49 were selected; and for IDI, eight chefs were selected. The survey included four steps of 'Awareness-First try-Needs-Future consumption'. The participants got to know kimchi through the Internet; for example, by visiting Korea and Hallyu, and suggested positive comments, including 'fancy' and 'exotic.' While satisfaction with kimchi sharply decreased due to taste and appearance in the first try of kimchi, it is important to provide the best first-try experience. It also showed that important needs for kimchi are 'hot sensation', 'crunchiness' and 'presentation'. They gave a negative answer to combination with traditional cuisines of their own country, but provided positive comments for benchmarking the use of traditional pickled foods. This study suggests that it may be necessary to implement a two-track strategy by the traditional kimchi as a 'strategic product' and localized kimchi as a 'key product'.

• Journal of the Korean Society of Clothing and Textiles
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• v.14 no.2
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• pp.129-136
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• 1990

The purpose of the study was to develope brand positioning map for ladies' ready-to-wear, to find out evaluative criteria in perception and preference to brands, and to persent the relationship between consumer's characteristics and brand preference. Subjects were selected for the housewives of middle and high socioeconomic classes living in Seoul area. A questionnaire including items of life style, self image, similarity between brands, preference degree to brands, and demographic variables was developed for the empirical study. The questionnaire was administrated to 137 housewives during fall in 1989. Data were analyzed by cluster analysis and multidimensional scaling method. The study had two research problems. The first research problem was to construct a brand perceptual map for ladies' ready-to-wear brands, selected for the study The perceptual map was constructed on the basis of brand similarity scores by multidimensional scaling method. As a result, brands were grouped into 4 clusters, and evaluative criteria for perceptual map were found to be fashionability (classic- fashionable) and familiarity (familiar-unfamiliar). The second problem was to construct a brand preference map for ladies' ready-to-wear brands, selected for the study. The preference map was constructed on the basis of brand preference scores by multidimensional scaling method. As a result, the brands were grouped into 4 clusters and evaluative critiera for preference map were found to be fashionability (unfashionable-fashionable) and image to age (mature-young directed). Also was shown the relationship among self image, age, socioeconomic class, and brand preference. The multidimensional scaling method was found to be useful as well as valid instrument for brand positioning research and the result can be utilized for establishing strategies for ladies' ready-to-wear brands.

• Journal of The Korean Association For Science Education
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• v.10 no.2
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• pp.67-72
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• 1990

Correct comprehension of the scientific terms is the bottom of understanding the general concepts contained is them. Therefore a study is required to analyze whether the students correctly understand the scientific terms. The associative method was used to evaluate the comprehensibility of the terms. The scientific terms in this study are selected in the textbook of science in the junior high school were selected. The frequency of the same associative word responsed and the frequency of no response from the selected students for given scientific terms were measured for 9 different groups. The terms which are not used in the daily life, especially for the terms with chinese character or abstract terms turn out to be difficult for the students to understand. It is purposed that the instructor should remember the importance of understanding the scientific term and carefully explain them to the science class.