• Journal of the Korean Data and Information Science Society
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• v.22 no.2
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• pp.335-351
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• 2011

In order to resolve data scarcity problem related to crisis, Oh and Kim (2007) proposed to use stability oriented approach which focuses a base period of financial market, fits asymptotic stationary autoregressive model to the base period and then compares the fitted model with the current market situation. Based on such approach, they developed financial market instability index. However, since neural network, their major tool, depends on the base period too heavily, their instability index tends to suffer from inaccuracy. In this study, we consider linear asymptotic stationary autoregressive model and neural network to fit the base period and produce two instability indexes independently. Then the two indexes are combined into one integrated instability index via newly proposed combining method. It turns out that the combined instability performs reliably well.

• Proceedings of the KSR Conference
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• 2009.05a
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• pp.1229-1234
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• 2009

The rolling stocks of KORAIL are KTX, Saemaulho Multiple Unit(PP), New Electrical Locomotive(DL), Electrical Locomotive(EL), Diesel Locomotive, Metropolitan Commuter Train(CDC), VVVF and Resistance Controlled Multiple Unit, etc. EMU with the maximum speed of 150km/h is under the test run at the moment. Electrical Multiple Units for mainlines with 180km/h speed are supposed to be introduced as a substitute for Saemaulho Multiple Unit which is scheduled to be out of service. But the specification standard for the control board design of train driver's cab does not exist and there is no a study for layout and type of controlling device with driver's ergonomical approach. That's why the types of controller and operating are different from rolling stocks, which has high possibility of driver's human error and needs education whenever a new car comes in. Based on the opinion poll of drivers, design specification of safety engineering and ergonomics for controlling devices and safety facilities can improve exact control for devices and deal quickly with an emergency so as to improve rolling stock safety and operational efficiency.

• The Research Journal of the Costume Culture
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• v.22 no.2
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• pp.346-359
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• 2014

Black Friday, a biggest holiday shopping season in the United States, has been regarded as a great opportunity that fashion retailers can dramatically increase their sales. However, there has been a lack of attention to consumers' shopping experiences on Black Friday from the consumer perspectives. The objective of this study is to explore consumer shopping experiences on Black Friday, in terms of consumer responses toward the experiences, shopping values, and any possible factors influencing the experiences. The method of critical incident technique was used with 198 critical incidents extracted from 165 responses of university students in the United States. As results, the shopping experiences on Black Friday were categorized into positive vs. negative shopping experiences. After that, the positive and negative experiences were respectively divided into two common themes: utilitarian shopping value vs. hedonic shopping value. In addition to the common themes, 12 categories were also emerged. Among positive experiences, utilitarian shopping experiences includes two categories of off-price shopping and shopping for expensive products, whereas hedonic shopping experiences includes three categories of impulse buying, holiday atmosphere, and shopping for the latest or luxury brand products. Among negative experiences, utilitarian shopping experiences includes four categories of modest discounts, out of stock, time-consuming queues, and fatigue of holiday shopping, while hedonic shopping experiences includes three categories of crowded environments, compulsive buying, and poorly managed stores. In conclusion, it is notable that consumer can undergo negative as well as positive shopping experiences on Black Friday. Implications and suggestions are also discussed.

• Journal of Digital Convergence
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• v.10 no.11
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• pp.315-321
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• 2012

Since technological innovation is such an important factor that it can determine a company's economic growth and competitive enhancement, all the companies make lots of investments and efforts for technological innovation. As outcomes of technological innovation, there are patents, trademark and copyrights, etc. and they are mostly approved as a legal right called 'Intellectual Property Right'. To activate such an intellectual property right, financing techniques are needed for enterprises to raise funds through collaterals, such as technological and intellectual patents. In reality, however, any IP-related financial system is not really activated due to the lack of surety-related regulations in Korea. Thus, on the premise that it is important to carry out an objective and reliable valuation on IP as a collateral for the activation of IP finance, this study intends to investigate various different methods of patent valuation needed for IP finance.

• Journal of the Korea Organic Resources Recycling Association
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• v.16 no.4
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• pp.50-56
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• 2008

Aqueous thermal liquefaction of rice, barley, wheat, and rapeseed straws was investigated to compare the amount of heavy oil with catalysts such as $K_2CO_3$, NaOH and KOH in the reaction temperature at $320^{\circ}C$ for 10 minutes. The reaction was carried out in a 5,000ml liquefaction system with dispenser and external electrical furnace. Raw materials (160g), 2,000ml of distilled water and 10% (wt/wt) of catalyst to plant residue were fed into the reactor. It was observed that the maximum heavy oil yield was about 29% from the feeding stock, barley straw, with addition of KOH. The caloric values of crude oil from different crop residues were ranged from 55% to 66% relative to the raw materials depend on crop residue. It was appeared that its maximum calorific value from wheat straw was approximately 6190 kcal/kg.

• Journal of Industrial Convergence
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• v.18 no.5
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• pp.1-13
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• 2020

The purpose of this study is to find out how much the investment effect of convertible bond(CB) is from the perspective of investors and to present efficient investment plans to investors. The research method is to investigate the coupon interest rate, maturity interest rate, conversion price, etc. for CBs. As a result of the study, it was analyzed that CB's investment efficiency was low because the conversion price excess days ratio was only about 1/4 of the conversion date. The conversion day yield was -6.3% and the maturity day yield was -5.2% on average. It was analyzed that the number of stocks with negative conversion day yield was 2.4 times higher than the number of positive stocks and 3.7 times higher than the number of positive stocks with a maturity day yield, so the expected return on equity conversion of CB was low.

• STI Policy Review
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• v.3 no.2
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• pp.111-129
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• 2012

The integration of products and services is being expanded in both manufacturing and service companies such as in Apple's iPod & iTunes, Amazon's Kindle, and Hyundai Motor Company's Mozen. This phenomenon has recently accelerated due to multiple factors including market change, lessening of differences in quality of products or services, the paradigm of participation and sharing, and deindustrialization and evolution toward becoming a service economy. The objective of this paper is to investigate and analyze the status and characteristics of integration of products and services in Korean firms and to suggest policy directions promoting this integration. Towards this purpose, income statements from the Korea Listed Companies Association (KLCA) database of companies listed on the Korea Stock Exchange are analyzed regarding the servitization of manufacturing firms as well as the productization of service firms. In addition, this research investigates the Korean Innovation Survey 2011 database for the service sector and 2010 database for the manufacturing sector in order to evaluate R&D activity in each. In the manufacturing sector, the average ratio of service sales (servitization) was low at 0.208, with bias in the level and distribution of ratios associated with the manufacturing sector. 18 out of a total of 23 sectors (78%) have low servitization, showing there's a long way to go for servitization in the Korean manufacturing sector. In the service sector, the average ratio of product sales (productization) was 9.53%, which is relatively high compared to that of the manufacturing sector. However, the distribution of ratios is also biased, as with the manufacturing sector. Based on this analysis, policy directions are proposed in terms of 1) R&D, 2) concept boost, 3) R&D result spread, 4) statistics, 5) infrastructure and 6) green growth.

• Journal of Families and Better Life
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• v.22 no.5
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• pp.59-73
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• 2004

Since 1980s' Korea had a great change on the housing culture by the supply of multi-family housing stock both on the macro-social and micro-social aspects. The purpose of this study was to examine the changes and the characteristics of housing environments which were estimated its modernization, and to examine the personal life under the change of housing environments. So I would like to revaluation the characteristics of modernization between the 1980s' and 1990s'. Therefore references were made to various papers, reports, the statistical data, newspaper reports, advertisements and magazines during that period. As a result, this paper came to the remarks as follows: 1. The success of modernization on the housing environments since 1980s' was the Quantitative growth of housing supply by multi-family housing. In spite of this, the Quantitative growth of housing supply and the improvement in Quality like housing space per person had the characters which was 'out of valence on the division'. 2. The Qualitative improvement of modem housing life by the development of housing industries could be said the improvement owing to develop of facilities and equipments. The introduction of up-to-date facilities and equipments realized the convenience and the rationality of living in the house. Although the improvement on the physical things deteriorated the modernized spaces to uniform things by commercial strategies. 3. The life in the multi-family housing which gives protection to personal privacy was settle down on the extremely individualized life without common things within the neighbors. Multi-family housing which was a production of process of modernization came true the growth in an appearance and the variety in the inside, but for the aspect of residents' everyday life in the multi-family housing, the Korean traditional relationship was collapsed and a sense of incompatibility within the residents was created.

• Journal of Ocean Engineering and Technology
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• v.32 no.5
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• pp.324-332
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• 2018

It is known that damages to the subsea cables used for electric power transmission between islands and countries, including renewable energy from offshore wind power, current, tides, etc., cost much to restore, which causes social and economic losses. Various types of fishing rigs and anchors have been reported to be the greatest hazards to subsea cables. It is possible to design and construct a suitable protection facility for a subsea cable by precisely estimating the underwater behavior of such hazardous apparatuses. In this study, numerical simulations of the underwater behaviors of various hazardous apparatuses were carried out using fluid-structure interaction (FSI) analysis as a basic study to simulate the actual behavior phenomena of hazardous apparatuses in relation to a subsea cable. In addition, the underwater drop characteristics according to the types of hazardous apparatuses were compared. In order to verify the accuracy of the FSI analysis method used in this study, we compared the test results for underwater drops of a steel ball bearing. Stock anchors, stockless anchors, and rocket piles, which were actually reported to be the cases of damage to subsea cables along the southwest coast of Korea, were considered as the hazardous apparatuses for the numerical simulations. Each hazardous apparatus was generated by a Lagrangian model and coupled with the fluid domain idealized by the Eulerian equation to construct the three-dimensional FSI analysis model. The accuracy of the numerical simulation results was verified by comparing them with the analytical solutions, and the underwater drop characteristics according to the types of hazard apparatuses were compared.

• Economic and Environmental Geology
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• v.31 no.2
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• pp.149-158
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• 1998

Volcanic rocks including rhyolitic tuff, rhyolite and welded tuff in the Bupyeong silver mine area form a topographic circular structure known as a resurgent caldera. Granitic rocks are emplaced inside and outside area of the circular structure. K-Ar dating and Nd-Sr isotope studies were carried out to invesitigate the origin and petrogenetic evolution of the rhyolitic and granitic magma in the Bupeong silver mine area. Whole rock K-Ar age ranges from 208 to 131 Ma for rhyolitic rocks. Radiometric ages for the granitic rocks are 167.6 Ma for pink feldspar biotite granite from inside granitic pluton of the circular volcanic body, 178.8 Ma for the Kimpo hornblende biotite granite and 111.8 Ma for the Songdo foliated granite from outside granitic plutons of the volcanic body. The radiometric age data indicates that the volcanic activities which are partly overlapped by granite plutonic activities in the Bupyeong mine area had recorded early Jurassic and early Cretaceous in age. Initial Sr and Nd isotopic ratios of the rhyolitic rocks ($^{87}Sr/^{86}Sr$=0.710~0.719 and $^{143}Nd/^{144}Nd$=0.5115~0.5118) are similar to those of granitic rocks ($^{87}Sr/^{86}Sr$=0.709~0.716 and $^{143}Nd/^{144}Nd$=0.5115~0.5116) from inside granite stock. This means that similar source materials of felsic magma responsibles for the Bupyeong volcanic rocks and inside plutonic rocks. Based on the Nd and Sr isotopic compositions, rhyolitic and granitic magmas in the Bupyeong area originated from the partial melting of the old continental crust which has Nd model age ranging from 1500 to 2900 Ma. This is analogous to those of the other Jurassic granitoids in South Korea.