• Journal of Korea Water Resources Association
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• v.33 no.5
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• pp.537-550
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• 2000

In this study, Neural Networks models were used to forecast daily streamflow at Jindong station of the Nakdong River basin. Neural Networks models consist of CASE 1(5-5-1) and CASE 2(5-5-5-1). The criteria which separates two models is the number of hidden layers. Each model has Fletcher-Reeves Conjugate Gradient BackPropagation(FR-CGBP) and Scaled Conjugate Gradient BackPropagation(SCGBP) algorithms, which are better than original BackPropagation(BP) in convergence of global error and training tolerance. The data which are available for model training and validation were composed of wet, average, dry, wet+average, wet+dry, average+dry and wet+average+dry year respectively. During model training, the optimal connection weights and biases were determined using each data set and the daily streamflow was calculated at the same time. Except for wet+dry year, the results of training were good conditions by statistical analysis of forecast errors. And, model validation was carried out using the connection weights and biases which were calculated from model training. The results of validation were satisfactory like those of training. Daily streamflow forecasting using Neural Networks models were compared with those forecasted by Multiple Regression Analysis Mode(MRAM). Neural Networks models were displayed slightly better results than MRAM in this study. Thus, Neural Networks models have much advantage to provide a more sysmatic approach, reduce model parameters, and shorten the time spent in the model development.

• KSBB Journal
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• v.22 no.2
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• pp.91-96
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• 2007

The saccharogenic liquid (SFW) obtained by the enzymatic saccharification of food wastes was used as a medium for production of bacterial cellulose (BC). The enzymatic saccharification of food wastes was carried out by the cultivation supernatant of Tricoderma inhamatum KSJ1 culture. Acetobacter xylinum KJ1 was employed for the BC production culture. Under the scaled-up aeration condition of 1.0 vvm, 5.64 g/L of BC was produced in 3 days cultivation in 50 L air circulation bioreactor using SFW medium with addition of 0.4% agar. The productivity was similar to that of 10 L air circulation bioreactor (5.84 g/L). This cultivation method with 50 L air circulation bioreactor decreasing shear stress and increasing oxygen transfer coefficient ($k_La$) was very useful in BC mass production. The physical properties, such as morphology, molecular weight, crystallinity, and tensile strength of BC produced by the static culture (A), the air circulation culture using 10 L bioreactor (B) and 50 L bioreactor (C) were investigated. The number average molecular weight of BCs produced under the different culture conditions (A-C) showed 2,578,000, 1,975,000, and 1,809,000, respectively. Tensile strength was 1.72 $kg/mm^2$, 1.19 $kg/mm^2$, and 1.18 $kg/mm^2$, respectively. All of the BCs had a form of cellulose I representing pure cellulose. The relative degree of crystallinity showed the range of 86.2$\sim$87.8%. BC production by the air circulation culture mode brought more favorable results in terms of the physical properties and its ease of scale-up. Therefore, it is expected that the new BC production method, the air circulation culture using SFW, would contribute greatly to BC-related manufacturing.

• Journal of the Korean Society of Costume
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• v.55 no.1 s.91
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• pp.25-42
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• 2005

Costume is a formative art expressed by active human unlike the field of other living formativeness, and an expression of social actions based on a style of culture in a period. Therefore, costume has a deep connection with a mode of living and is recognized as a 'culture for living', and is more characteristic culture than all metaphysical cultures including architecture, craft, painting, and sculpture. Therefore, it expresses wearer's status or social standing, and furthermore, ideas and values of the times with aesthetic features in their form, color, materials, and pattern, so it is expressed as a mirror reflecting the phases of the times as. Korean costume had been dressed until the period of the Joseon Dynasty without a great change and started to be simplified in a simple style on the grounds of inconvenience in behaviors with the opening of an interchange of Western culture in the civilized period. And, this movement had been continued and Korean costume had been applied as an everyday dress under the name of 'Reformed Korean Costume'. Since the middle phase of 1980s, it aroused many people's interests with the introduction of designs focused on activity and convenience. In 1990's, many people had taken a growing interest in Korean costume with development of various designs keeping pace with the internationalization period and Korean Costume had been revitalized under the name of 'The Modernized Korean Costume'. And, since the 21st century, the advanced communication and full-scaled import of Western fashion have made the introduction of many fashion information in the world into Korea, affected greatly the fashion market, led consumers' sensitivity on a trend to be increased. Therefore, a design accepting a trend 'The Modernized Korean Costume' with fashions has risen. Second, this study is an attempt to suggest a revitalization method of domestic casual Korean costume brands by developing and suggesting competitive and highly value-added products with connection of practicality, variety, and highly sensitive fashion styles. For theoretical study, domestic and foreign literatures, academic journals, professional monthly magazines, and newspapers were examined. And, a process of change and features of the Korean fashion since the civilization period, and concept, features and images of casual Korean costume were analyzed, On the basis of analyzing image, features, and consumers' preference of the modernized Korean costume, a design development plan was established and 10 suits of costume were designed and made.

• Journal of the Korea institute for structural maintenance and inspection
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• v.24 no.6
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• pp.17-24
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• 2020

In this study, series of nonlinear seismic analysis were performed on a reinforced concrete intake tower surrounded by water. To consider the fluid effect around the structure, analysis models were composed using an added mass and CEL approach. At this time, the implicit method was used for the added mass model, and the explicit method was used for the fluid structure interaction model. The input motions were scaled to correspond to 500, 1000, and 2400 years return period of the same artificial earthquake. To estimate the counteractivity of the fluid coupled model, models without fluid effect were constructed and used as a reference. The material models of concrete and reinforcement were selected to consider the nonlinear behavior after yielding, and analysis were performed by ABAQUS. As results, in the acceleration response spectrum of the structure, it was found that the influence of the surrounding fluid reducing the peak frequency and magnitude corresponding to the fundamental frequency of the structure. However, the added mass model did not affect the peak value corresponding to the higher mode. The sectional moments were increased significantly in the case of the added mass model than those of the reference model. Especially, this amplification occurred largely for a small-sized earthquake response in which linear behavior is dominant. In the fluid structure interaction model, the sectional moment with a low frequency component amplifies compared to that of the reference model, but the sectional moment with a high requency component was not amplified. Based in these results, it was evaluated that the counteractivity of the additive mass model was greater than that of the fluid structure interaction model.

• Asia Marketing Journal
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• v.15 no.4
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• pp.1-32
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• 2014

The purpose of this paper is to investigate upon a diversification strategy through market creation of CJ Group, which has contributed in positioning of the firm as one of the leading conglomerates in South Korea. With such objective, the background of CJ Group, followed by its business diversification strategies were explored, with reference to several case studies. The history of CJ Group began with establishment of CheilJedang Industrial Corporation in 1953, as the first domestic sugar producer and exporter of South Korea. The corporation gradually expanded its business ever since at both national and global level, to include the fields of food production, pharmaceutical, biotechnology, and life chemicals. Later, CheilJedang (CJ) Group was established as an affiliate of CheilJedang Industrial Corporation. With such independence, extension of business has been witnessed across the industries of media, entertainment, finance, information technology and distribution. Thus, the current CJ Group pursues to define itself as a progressive global living culture company with four major business categories from food and food service, biotechnology, entertainment and media, and logistics. Despite its success in today's market, CJ Group underwent hardships in its business diversification in 1990s due to indiscreet management, along with the Asian financial crisis. Here, many firms overcame the financial difficulties by taking advantage of the exchange rate for overseas expansion. Though, CJ Group tried to differentiate itself by focusing on the domestic market by creating something out of nothing. Hence, CJ Group takes a unique position among many cases of business diversification and their categorization. In an effort to identify and classify the types of growth experienced by the top 30 companies in South Korea, the firms were categorized into four groups according to their diversification strategies adapted after the Asian financial crisis. Based on the mode and time of entry, corporations were identified either as the 'Explorer', 'Invader', 'Venture Capitalist', or 'Assimilator'. Here, the majority of the firms showed the qualities of Invader, entering mature markets through large-scaled mergers and acquisitions. However, CJ Group was the only firm that was categorized as an Explorer, for its focus on the newly emerging service sector in culture-contents industry. This diversification strategy through market creation is worth examining, due to its contribution in generating simultaneous growth between the market and the company itself. Diverse brands of CJ Group have been referred to as case studies in this regard, from 'Hatban', 'Cine de Chef', 'VIPS' to 'CJ GLS'. These four businesses, each to represent processed food, film, restaurant service, and logistics industries respectively, show CJ Group's effectiveness in creating a whole new category of goods and services that are innovative. In fact, such businesses not only contributed in advancement of consumers' wellbeing, but toward generating additional value and employment. It is true that the diversification strategy of CJ Group requires long-term capital investment with high risk, compared to the other strategies mentioned in the paper. However, this model does create high employment and additional values that are positive to both the society and the firm itself. Therefore, the paper comes to a conclusion that the diversification strategy through market creation conveys the most positive impact relative to the others.