• KSCE Journal of Civil and Environmental Engineering Research
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• v.5 no.1
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• pp.101-111
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• 1985

The initial stage of an investigation aimed at setting up a system for the prediction of tides and surges in the Yellow Sea and East China Sea are described. The structure of the proposed scheme is to take pressure data from the weather charts, then to process the data in order to provide the necessary meteorological forcing data to the sea model, which then computes the associated waterlevels and currents. The procedure of predicting the drift and spreading of pollutants using the flow field from the tide and surge computation scheme are also briefly described. Some preliminary results of predicting oil spreading in the Inchon Bay are presented and discussed. An indication of further development of the system is also given.

• Ocean and Polar Research
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• v.36 no.3
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• pp.289-302
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• 2014

This paper aims to evaluate the indirect economic damages to anglers of the marine recreational charter caused by marine pollution associated with the Herbei Spirit vessel, which spilled 12,547 kl of crude oil in Taean coastal areas in December 2007. In order to evaluate the indirect cost to anglers of the charter fishing, consumer surplus for charter fishing is estimated using a Poisson model (PM), a negative binomial model (NBM), a truncated Poisson model (TPM), and a truncated negative binomial model (TNBM), which account for the characteristics of count data (non-negative discrete data), for individual travel cost method (ITCM). Because of over-dispersion problem in PM and TPM, NBM and TNBM are considered to be more appropriate statistically. All parameters such as income, fishing careers, travel cost and catch that are estimated are statistically significant and theoretically valid. Based on TNBM results, consumer surplus per trip and per person was estimated to be 277 thousand won, total consumer surplus per person and per year about 2.3 million won, and the marginal effect of consumer surplus on % changes in catch rate is about 33 thousand won. The consumer surplus was converted into total indirect economic damages for aggregation which are evaluated to be 125 billion won, reflecting the number of anglers and damage rate.

• Asia-Pacific Journal of Business
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• v.10 no.2
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• pp.1-12
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• 2019

Collaborative research and development (R&D) has been encouraged based on the belief that knowledge spill-over is mutually beneficial for partners. Although the benefits are supported by science and technology policy research, the risk of R&D collaboration has not been extensively discussed. Two independent studies suggest that there are risks associated with the overuse of collaborative research frameworks. Two sets of R&D collaboration data were analyzed: between the national bio-technology research program and 1) Data Envelop Analysis (DEA), and 2) between Stochastic Frontier Analysis (SFA). In the case of SFA, output measures were integrated into a single output, with weights extracted from research programme managers' responses to the questionnaire. While the DEA result demonstrated the inefficiency of collaborative research, SFA did not. Unlike previous research highlighting risks associated with disclosing proprietary R&D and potential conflict of interest, our study indicates that the transaction's social cost affects collaborative research efficiency. Therefore, governments promoting R&D collaborations should be carefully managed, and policy makers must reconsider the strict conditions governing compulsory collaborative R&D programs.

• Journal of Korean Port Research
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• v.11 no.2
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• pp.241-255
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• 1997

Three dimensional numerical model is used to simulate the circulation patterns in the Gamcheon Bay located in Pusan, Korea and compared with the observed data. The model is forced by winds, tidal elevation at open boundaries, and warm water discharged from the outfall of power plant, Turbulence mixing coefficients are calculated according to a ${\kippa}-{\varepsilon}$ turbulence closure submodel. Temperature, salinty and current are measuted extensively and these measuted data are compared with the simulation results. Eddy-like features exist both in observed data dna simulation results. These eddies are the results of interaction with the weak tidal current, wind driven current and warm water discharges. Compensational deeects are also found to exit such that while surface current is strong, bottom current tends to weaken and vice versa.

• Nuclear Engineering and Technology
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• v.29 no.3
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• pp.240-250
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• 1997

Liquid sodium is widely used as a coolant of LMR(Liquid Metal Reactor) because of its physical and nuclear properties. However, the liquid sodium is very chemically reactive with oxygen and water so that the study on the sodium fire plays an important role in the LMR safety analysis. In this study, a sodium fire model is suggested to analyze the sodium pool fire where both the flame and the reaction products are considered. And also, sodium pool fire analysis computer code, SOPA, is developed. The sensitivity study on the experimental parameters such as the thermal radiation from flame to atmospheric gas, the vessel cooling and the duration of sodium spill was performed. The results showed good agreements with experimental data in the literature.

• Journal of the Korean Society of Marine Environment & Safety
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• v.19 no.2
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• pp.129-137
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• 2013

In order to obtain quantitative basic data for marine oil pollution prevention, the statistics of oil spill incidents in Korea and in the world for 20 years from 1993 to 2012 were collected and analyzed with relation to the number of oil spills and the amount of oil spilt. In Korea for 20 years, total number and average annual number of oil spills were 6,608 cases and nearly 330 cases/year, respectively, and total volume and average annual volume of oils spilt were 57,328 kL and nearly 2,866 kL/year, respectively. Due to major oil spills from oil tankers, annual volumes of oils spilt in Korea were sharply increased to 15,388 kL in 1993, 15,773 kL in 1995, 3,428 kL in 1997 and 13,008 kL in 2007. In case of worldwide oil spills for 20 years, total number and average annual number of oil spills of 8 kL (or 7 tonnes) and above were 420 cases and 21 cases/year, respectively, and total amount and average annual amount of oils spilt 8 kL (or 7 tonnes) and above were about 800,000 kL (or 704,000 tonnes) and about 40,000 kL/year (or 35,200 tonnes/year), respectively. Major oil spills from oil tankers increased massively annual amounts of oils spilt worldwide to about 159,000 kL (or 140,000 tonnes) in 1993, about 147,600 kL (or 130,000 tonnes) in 1994, about 90,900 kL (80,000 tonnes) in 1996, about 81,800 kL (72,000 tonnes) in 1997 and about 76,100 kL (or 67,000 tonnes) in 2002. Obvious correlation between annual number of oil spills and annual amount of oil spilt was not found in both Korea and the world, while both annual number and annual volume tended to decrease with the lapse of year in both Korea and the world, though there were wide fluctuations from year to year in both annual number of oil spills and annual amount of oils spilt worldwide and in Korea for 20 years. From 2008 to 2012 worldwide, there were sharp decreases in both annual number and annual amount of oil spills. In particular, no oil spill of 800 kL (or 700 tonnes) and above occurred in the year of 2012.

• Journal of the Korean Society for Marine Environment & Energy
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• v.18 no.4
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• pp.304-309
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• 2015

To evaluate the degree of contamination caused by oil spill accident in the sea, the in-situ sensors which are based on the scientific method are needed in the real site. The sensors which are based on the fluorescence detection theory can provide the useful data, such as the concentration of oil. However these kinds of sensors commonly are composed of the ultraviolet (UV) light source such as UV mercury lamp, the multiple excitation/emission filters and the optical sensor which is mainly photomultiplier tube (PMT) type. Therefore, the size of the total sensing platform is large not suitable to be handled in the oil spill field and also the total price of it is extremely expensive. To overcome these drawbacks, we designed the fluorimeter for the oil spill detection which has compact size and cost effectiveness. Before the detail design process, we conducted the experiments to measure the excitation and emission spectrum of oils using five different kinds of crude oils and three different kinds of processed oils. And the fluorescence spectrometer were used to analyze the excitation and emission spectrum of oil samples. We have compared the spectrum results and drawn the each common spectrum regions of excitation and emission. In the experiments, we can see that the average gap between maximum excitation and emission peak wavelengths is near 50 nm for the every case. In the experiment which were fixed by the excitation wavelength of 365 nm and 405 nm, we can find out that the intensity of emission was weaker than that of 280 nm and 325 nm. So, if the light sources having the wavelength of 365 nm or 405 nm are used in the design process of fluorimeter, the optical sensor needs to have the sensitivity which can cover the weak light intensity. Through the results which were derived by the experiment, we can define the important factors which can be useful to select the effective wavelengths of light source, photo detector and filters.

• Journal of the Korean Society of Marine Environment & Safety
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• v.22 no.7
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• pp.846-853
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• 2016

This study prioritizes Noxious Liquid Substances (NLS) transported by sea via a risk-based database containing 596 chemicals to prepare against NLS incidents. There were 158 chemicals transported in Korean waters during 2014 and 2015, which were prioritized, and then chemicals were grouped into four categories (with rankings of 0-3) based on measures for preparedness against incident. In order to establish an effective preparedness system against NLS spill incidents on a national scale, a compiling process for NLS chemicals ranked 2~3 should be carried out and managed together with an initiative for NLS chemicals ranked 0-1. Also, it is advisable to manage NLS chemicals ranked 0-1 after considering the characteristics of NLS specifically transported through a given port since the types and characteristics of NLS chemicals relevant differ depending on the port. In addition, three designated regions are suggested: 1) the southern sector of the East Sea (Ulsan and Busan); 2) the central sector of the South Sea (Gwangyang and Yeosu); and 3) the northern sector of the West Sea (Pyeongtaek, Daesan and Incheon). These regions should be considered special management sectors, with strengthened surveillance and the equipment, materials and chemicals used for pollution response management schemes prepared in advance at NLS spill incident response facilities. In the near future, the risk database should be supplemented with specific information on chronic toxicity and updated on a regular basis. Furthermore, scientific ecotoxicological data for marine organisms should be collated and expanded in a systematic way. A system allowing for the identification Hazardous and Noxious Substances (HNS) should also be established, noting the relevant volumes transported in Korean waters as soon as possible to allow for better management of HNS spill incidents at sea.

• Earthquakes and Structures
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• v.8 no.3
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• pp.779-799
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• 2015

The slosh height and the possibility of water spill from rectangular Spent Fuel Storage Bays (SFSB) and Tray Loading Bays (TLB) of Nuclear power plant (NPP) are studied during 0.2 g, Safe Shutdown Earthquake (SSE) level of earthquake. The slosh height obtained through Computational Fluid dynamics (CFD) is compared the values given by TID-7024 (Housner 1963) and American concrete institute (ACI) seismic codes. An equivalent amplitude method is used to compute the slosh height through CFD. Numerically computed slosh height for first mode of vibration is found to be in agreement the codal values. The combined effect in longitudinal and lateral directions are studied separately, and found that the slosh height is increased by 24.3% and 38.9% along length and width directions respectively. There is no liquid spillage under SSE level of earthquake data in SFSB and TLB at convective level and at free surface acceleration data. Since seismic design codes do not have guidelines for combined excitations and effect of higher modes for irregular geometries, this CFD procedure can be opted for any geometries to study effect of higher modes and combined three directional excitations.

• Journal of Korean Society of Transportation
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• v.23 no.2
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• pp.37-50
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• 2005

This study analyzes the effect of airport investment on GRDP(Gross Regional Domestic Product) using Regional Production Function with public investment on social infrastructure. Particularly it includes the spillover effect of airport investment on the economies of neighbor regions beyond border. We estimate regional production function with the independent variable of airport investment stock using panel data with regional cross-section and time-series data. In the analysis with aggregate data of all industries, it shows the positive relationship between airport investment and GRDP which implies the affirmative effect of airport investment on regional economy in the aspects of direct and indirect spill-over effects. On the contrary, the research results of each industry do not appear to be the same. With the different characteristics of each industry, the direct and indirect effect may not be the same and the SOC investment contributes to the restructuring of regional economy by altering the industrial organizations of any specific region and its neighbors.