• Korean Journal of Agricultural and Forest Meteorology
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• v.1 no.2
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• pp.119-126
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• 1999

A numerical model using soil surface energy balance and soil heat flow equations to estimate mulched soil temperature was developed. The required inputs data include weather data, such as global solar radiation, air temperature, wind speed, atmospheric water vapor pressure, the optical properties of mulching material, and soil physical properties. The observed average soil temperature at 50 cm depth was used as the initial value of soil temperature at each depth. Soil temperature was simulated starting at 0 hour at an interval of 10 minutes. The model reliably described the variation of soil temperature with time progress and soil depth. The correlation between the estimated and measured temperature yielded coefficient values of 0.961, 0.966 for 5cm and 10cm depth of the bare soil, respectively, 0.969, 0.965 for the paper mulched soil, and 0.915, 0.938 for the black polyethylene film mulched soil. The percentages of absolute differences less than 2$^{\circ}$C between soil temperatures measured and simulated at 10 minute interval were 97.4% and 98.5% for 5 cm and 10cm for the bare soil, respectively, and 95.8% and 97.4% for the paper mulched soil, and 70.1% and 92.5% for the polyethylene film mulched soil. The results indicated that the model was able to predict the soil temperature fairly well under mulched condition. However, in the night time, the model performance was a little poor as compared with day time due to the difficulty of accurate determination of the atmospheric long wave radiation.

• Journal of the Economic Geographical Society of Korea
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• v.17 no.4
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• pp.786-800
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• 2014

The aim of this article is to analyze the relationship between the change of the diversity of the industrial structure, and regional employmentability and the intensification of regional competitiveness, and consequently, is to present policy implications. As a result of the analysis of the whole industry such as the primary, secondary and tertiary industry in Chungnam Province, the existing strategic implementation on the employmentability and regional competitiveness throughout the policy on the existing specialized industries can be regarded as appropriate. However, under the condition that danger and stability in each industry are fluctuated and the internal and external circumstances are varied, the detailed analysis and rapid policy prescription on the primary and tertiary industry are required. Along with these results, policy implications are as follows; Firstly, in terms of effectiveness, regional policy are simultaneously conducted along with industrial, technological and regional development's policies while consider ing complex and comprehensive characteristics of the regional industry and rapid changing the global market conditions. Secondly, with respect to equity, regional policy is needed to implement by reducing the socio-economic gap across regions and mixing regional and sectoral policies along with regional and local uniqueness.

• Journal of the Korean Society of Marine Environment & Safety
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• v.22 no.7
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• pp.773-781
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• 2016

The present SOLAS Convention has maintained safety regulations in a largely prescriptive form and this has become overly prescriptive now. The prescriptive rules do not properly reflect technical advances and changing environments in the maritime sector in a timely manner. The purpose of this study is to provide preliminary research to lay a foundation for the development of a new regulatory framework based on safety performance which is not a prescriptive rule making bases. This study reviewed the concept and characteristics of a minimum requirement, the implications of safety regulations in terms of strategic, commercial and technical aspects, the compensative correlation between constructional requirements and operational measures, the concept of safety with regard to final stage confirmation of functions, expansion of implementers and objects of safety regulations, and the balance between safety and environmental protection requirements. Based on these research, 10 principles for the rule formulation process has been suggested such as consideration on the hardware requirements and software requirement, the multi-stage approval concept, new safety concerns for complex shipboard systems, considerations on the human element, regulatory impact assessments and measures to reduce administrative burdens.

• Journal of Chest Surgery
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• v.30 no.11
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• pp.1092-1096
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• 1997

Thromboelastography(TEG) enables a global assessment of hemostatic function to be made from a single blood sample, documenting the interaction of platelets with protein coagulation cascade from the time of the initial platelet-fibrin interaction, through platelet aggregation, clot strengthening and fibrin cross linking to eventual clot Iysis. Thirty-five patients(mean age 34$\pm$ 12) undergoing open heart surgery from April 1st, 1996 to August 31th, 1996 were investigated at preoperatively and immediate, one hour, and 24 hours after cessation of cardiopulmonary bypass using TEG. Comparisons were made between classic hematological indices and TEG data. There were statistically significant correlation between maximal amplitude(MA) and platelet count before CPB, activating clotting time(ACT) and TEG date(R time, K time and a angle) at 24-hour after CPB. The data on the predictive accuracy for postoperative bleeding at 24-hour after CPB, the TEG was significantly better than ACT(57%) or the coagulation profiles(43%) as a predictor of postoperative bleeding, with an accuracy rate of 100% (P=0.0043). In conclusion, TEG seems to be easy to use, clinically accurate, cost effective and provides data which can effectively manage a patient's hemostasis.

• Environmental and Resource Economics Review
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• v.26 no.4
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• pp.577-612
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• 2017

In response to climate change, Korea is attempting to shift the paradigm of energy and climate change policies by introducing carbon pricing based on market mechanisms. While policy adoption is proceeding at a rapid pace, the introduction of carbon pricing has been faced with great opposition from industry. This study measures to what extent Korean companies understand and accept carbon pricing, using data from a questionnaire survey covering energy consuming companies in 2012, when discussions between the government and such companies about the introduction of a domestic emission trading system were active. It further identifies how preparations and practices for carbon and energy management of companies correlate with their policy understanding and acceptance. The analysis results show that the surveyed companies indicate moderate understanding of, as well as resistance to carbon pricing policies, while appreciating the economic incentives and accepting the mandatory regulations in this phase. Companies' understanding is more related to characteristics, i.e., sector, size, etc. than external pressures. This study found that the extent to which companies understand policy is the essential factor in their policy acceptance and related practices. In particular, understanding of carbon policy significantly influences their managerial practices and voluntary activities for carbon and energy practices. This study substantiates the correlation between the level of policy understanding of a company and its carbon and energy practices - something that all countries seeking to introduce carbon pricing in response to climate change should consider prior to policy actually being implemented; in other words, enhancing the understanding of major policy subjects of the new instrument is a key policy strategy that should be elaborated as it will lead to better performance of companies and smoother policy implementation.

• Journal of the Korean Society of Combustion
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• v.20 no.4
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• pp.34-41
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• 2015

Oxy-methane nonpremixed flames diluted with $CO_2$ were investigated to clarify impact of radiation heat loss and chemical effects of additional $CO_2$ to oxidizer stream on flame extinction. Flame stability maps were presented with functional dependencies of critical diluents mole fraction upon global strain rate at several oxidizer stream temperatures in $CH_4-O_2/N_2$, $CH_4-O_2/CO_2$, and $CH_4-O_2/CO_2/N_2$ counterflow flames. The effects of radiation heat loss on the critical diluent mole fractions for flame extinction are not significant even at low strain rate in nonpremixed $CH_4-O_2/N_2$ diffusion flame, whereas those are significant at low strain rate and are negligible at high strain rate (> $200s^{-1}$) in $CH_4-O_2/CO_2$ and $CH_4-O_2/CO_2/N_2$ counterflow flames. Chemical effects of additional $CO_2$ to oxidizer stream on the flame extinction curves were appreciable in both $CH_4-O_2/CO_2$ and $CH_4-O_2/CO_2/N_2$ flames. A scaling analysis based on asymptotic solution of stretched flame extinction was applied. A specific radical index, which could reflect the OH population in main reaction zone via controlling the mixture composition in the oxidizer stream, was identified to quantify the chemical kinetic contribution to flame extinction. A good correlation of predicted extinction limits to those calculated numerically were obtained via the ratio between radical indices and oxidizer Lewis numbers for the target and baseline flames. This offered an effective approach to estimate extinction strain rate of nonpremixed oxy-methane flames permitting air infiltration when the baseline flame was taken to nonpremixed $CH_4-O_2/N_2$ flame.

• Journal of Digital Convergence
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• v.18 no.9
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• pp.103-112
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• 2020

The purpose of this study is to examine the current status and components of Korean National Debt and to analyze the effects of each component on National Debt. In the Korean Statistical Information Service (KOSIS), we searched for data such as General Accounting Deficit Conservation, For Foreign Exchange Market Stabilization, For Common Housing Stability, Local Government Net Debt Public Funds, etc that constitute National Debt. The analysis period used a total of 23 annual data from 1997 to 2019. The data collected in this study use the rate of change compared to the previous year for each component. Using this, this study attempted index analysis, numerical analysis, and model analysis. Correlation analysis result, the National Debt has a high relationship with the For Common Housing Stability. For Foreign Exchange Market Stabilization, Public Funds, etc., but has a low relationship with the Local Government Net Debt. Since 1997, National Debt has been increasing similarly to the For Foreign Exchange Market Stabilization, For Common Housing Stability and Public Funds etc. Since 2020, Korea is expected to increase significantly in terms of For Common Housing Stability and Public Funds, etc due to Corona19. At a time when the global economic situation is difficult, Korea's National Debt is expected to increase significantly due to the use of national disaster subsidies. However, if possible, the government expects to operate efficiently for economic growth and financial market stability.

• Journal of the Korean earth science society
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• v.23 no.4
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• pp.349-356
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• 2002

In an effort to properly assess the validity of spaceborne radar altimeter measurements, we made a direct comparison of two different sea surface heights (SSH) acquired by both Topex/Poseidon (T/P) satellite and in-situ tide-gauges (T/G). This comparative analysis was conducted using the data sets collected from three locations along the eastern coast of Korea which include: Ulleungdo, Pohang, and Sokcho. In the course of the analysis of satellite altimeter, information of SSH was extracted from the T/P MGDR data sets through the application of both atmospheric and geophysical corrections. To compare the T/P data sets in parallel basis, the T/G data sets were averaged using the measured values within the peripheral radius of 55km. When compared among different locations, the compatibility between the two methods was much more significant in an offshore location (Ulleungdo) than the two onshore locations (Pohang, Sokcho). If the low-pass filtered results were compared among the sites, the offshore site exhibited the best correlations between the two methods (correlation coefficient of 0.91) than those of the onshore sites. These large differences in the strength of correlations among different locations are due to the deformation of M2, S2, and K1 tidal components used in the tidal model. In case of the offshore location, the compatibility of the two different methods were improved systematically by the low-pass filtering with an increase of the filtering duration such as up to 200 days.

• Journal of Korean Society of Forest Science
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• v.108 no.4
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• pp.513-521
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• 2019

With rapid climate change and increasing global warming, the distribution of evergreen broad-leaved trees (EBLTs) is gradually expanding to the inland regions of Korea. The aim of the present study was to analyze the survival rate of 148 EBLT plantations measuring 180 ha and to determine the optimal plantation size that would help in coping with climate change in the warm, temperate climate zone of the Korean peninsula. For enhancing the reliability of our estimated survival model, we selected a set of 11 control variables that may have also influenced the survival rates of the EBLTs in the 148 plantations. The results of partial correlation analysis showed that the survival rate of 67.0±26.9 of the EBLTs in the initial plantation year was primarily correlated with plantation type by the crown closure of the upper story of the forest, wind exposure, and precipitation. For predicting the probability of survival by quantification theory, 148 plots were surveyed and analyzed with 11 environmental site factors. Survival rate was in the order of plantation type by the crown closure of upper story of the forest, wind exposure, total cumulative precipitation for two weeks prior to planting, and slope stiffness in the descending order of score range in the estimated survival model for the EBLTs with the fact that survival rate increased with shade rate of upper story to some extent.

• Management & Information Systems Review
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• v.35 no.2
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• pp.221-254
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• 2016

With increasing interest of health due to population aging, medical device industry is highlighted as a promising industry. However, Korea medical device industry is not enough market competitiveness compared to global company due to a narrow domestic market and a small company structure. In order to retain the national competitiveness, it is necessary that we have to derive a central technology and its trend. This study has predicted a central technology for medical device industrial using patent network analysis. The central technology is defined as a key technology that is connected to most other technologies and that significantly affects them. For the empirical study, we conducted social network analysis using covariance and correlation coefficient between IPC codes extracted from medical device patents, introduced by Jun(2012). A social network is a social structure of diverse items as well as of human beings. In this study, we set each medical device as a node in an SNA and analyze the Degree values between them. Also, Korea health industrial statistics system are utilized for verification of selected central technology. As a result, we found that the central technology is located on the medical device items, which are listed higher the amount of production. The central technology selected through the proposed methodology will provide a inspiration for establishment of R&D policy.