• Journal of the Korean Data and Information Science Society
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• v.15 no.2
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• pp.355-365
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• 2004

Kim et al.. (2003) developed an Economic Instability Index (EII) by using mean squared error (MSE) from the neural network (NN) trained on the 1995 KOSPI. In this paper we study validity of the NN. For this we compare the NN with the well known Box-Jenkins linear auto-regressive processes. Our conclusive understanding of the problem is that the NN provides quite effective EII because it tends to overfit.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.68 no.1
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• pp.167-171
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• 2019

This paper is to consider an issue on the way to initialize the integrator in PID roll controller. A performance index including the 2 norms of roll angle and control signal is introduced to regulate initial roll angle and roll rate in an efficient way. And then we suggest the optimal value to initiate the integrator in PID roll controller by minimizing the performance index. The proposed method shows its effectiveness by showing a demonstrative design example.

• Journal of the Korean institute of surface engineering
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• v.55 no.6
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• pp.383-389
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• 2022

Natural(outdoor) and accelerated(artificial) weathering tests were performed to investigate their influence on polycarbonate. The polycarbonate materials were prepared of various formulations divided into three batches, with existing, development materials1, development materials2, containing mixture of UV additives. Weathering tests were carried out as outdoor weathering(Seosan, South Korea) and accelerated weathering(xenon-arc), and the results analysis were evaluated based on yellow-index(YI), scanning electron microscope(SEM/EDS), energy dispersive x-ray spectroscopy(XRD), and gel permeation chromatography(GPC). Among the three materials, processing method development materials1 with UV stabilizer was excellent in weathering. This study can provide basic data for standardization of development and performance evaluation on livestock barn roof.

• Proceedings of KOSOMES biannual meeting
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• 2018.06a
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• pp.33-33
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• 2018

• Proceedings of KOSOMES biannual meeting
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• 2018.06a
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• pp.44-44
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• 2018

• Proceedings of the KSCN Conference
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• 2004.12a
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• pp.105-105
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• 2004

• Journal of the Korean Society of Marine Environment & Safety
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• v.18 no.3
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• pp.185-191
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• 2012

Most of Korean farms have been developed in the semi-closed bay, and its position is very vulnerable to the coastal contamination due to the long term and the high density. So, mariculture management is very essential for the sustainable aquaculture. Some of the specific ways would be the assessment of the optimal stocking density for mariculture management zone and this has to consider both the suitable site selection and the assessment of ecological carrying capacity. Habitat suitability index(0.0 totally unsuitable habitat, 1.0 optimum habitat) and ecological indicator(Filtration pressure indicator) was used to assess the stocking density for oyster farms in Geoje-Hansan Bay. Geoje Bay showed the higher habitat suitability index value 0.75 than Hansan Bay 0.53, indicating that Geoje Bay is more suitable for oyster farming. Ecological indicator showed different stocking density according to the coastal characteristics in Geoje-Hansan Bay. Consequently, it is desirable that the stocking density in Geoje Bay should reduce average 40% and Hansan Bay, average 60% than present, in order to meet the ecological carrying capacity. The assessment of the stocking density could solve various problems such as the coastal contamination, environmental aggravation and the productivity decrease and this study could be a scientific basis to establish the policies for mariculture management.

• The Journal of the Korea Contents Association
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• v.13 no.4
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• pp.440-451
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• 2013

Advancement of science technology, combined with other technologies including smart clothing, enables value added product developments and market creation. Accordingly, it became necessary to identify technology trends promptly and to prepare future technology road map. For this purpose, many bibliometric analysis using thesis and patents have been made. However, few such attempts are made in clothing study. Thus, the study examined the latest technology trends and future technology development directions of smart clothing from empirical bibliometric analysis based on smart clothing patent documents. In addition, comparative analysis was made about the market leadership and technology development capability of core sectors by countries utilizing market reach index expressed as patent families and technology development index. The study revealed that overall smart clothing technology development trends has been continuously increasing since 2000. Also the results confirmed that it is in the development stage from the fact that each year the number of patents and patent applicants in portfolio analysis also has been increasing. In addition, comparative results of patent market share and market reach index, with the highest in electronics/ICT technology sectors, indicated that this is the technology sector with competitive acquisition of comparatively advanced technology and market expansion. The analysis methodology of economic value of technology including the presented market reach index in this report is expected to be utilized in the process to identify the current positioning of core technology and future development direction.

• Journal of Korea Port Economic Association
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• v.20 no.1
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• pp.1-20
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• 2004

The purpose of this paper is to analyze the degree of cargo concentration at Korean ports using Theil's Entropy and to compare the results with those of Gini coefficient, Hoyle(1983), and Hirshmann-Herfindahl models. The entropy indices were compared with other models after measuring the cargo concentration for the period of 1981-2000 among the 18 Korean ports. The core results of empirical analysis are as follows: first, the empirical results of entropy indices show the following trends: all the ports(concentration except 1996's slight deconcentration), ports in Western area(deconcentration in 1990s and slight concentration in 2000), ports in Southern area(deconcentration in 1980s and 1990s except concentration in 2000), and ports in Eastern area(continuous trends of concentration). However, competition power will be decreased if concentration is increased, because of the character of entropy index. The empirical results of 4 indices except Hoyle model show the comparatively same directions in terms of trends. This study found out the similar results among the following models: All the ports(entropy index & Gini coefficient & H-H model), ports in Western area(Entropy index &Hoyle model), ports in Southern area(Entropy index & Gini coefficient), and ports in Eastern area(Entropy index & H-H index).The policy planner of Korean ports should find out the determination factors of concentration and deconcentration of each ports and decide the investment priority, size and scope for balancing the development of regional ports.

• Journal of the Korean Society for Library and Information Science
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• v.38 no.4
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• pp.271-289
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• 2004

In this study, we analyze out citing and cited references among researchers, using KSCI (Korean Science Citation Index) database that is developed by KISTI. we generate and analyze that impact factor and immediate index with same method in JCR's. KSCI's impact factor and immediate index compared to JCR's, and with this basis, this study propose the need of development KSCI database and present new service model for evaluate of domestic journals.