• Korean Journal of Construction Engineering and Management
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• v.8 no.1 s.35
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• pp.66-77
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• 2007

With the electricity industry structure reformation of the government in April, 2001, Korea Power Electric Corporation was divided in to Korea water power nuclear power and 5 thermal power plant. After, various delivery method is introduced and applied for active profit creation according to the competition between each development companies for the public company privatization. However, the current situation does not satisfy the project participant by selecting the delivery method without reflecting the business goal and project characteristics of power plant construction business. The objective of this study is to research the influencing factors that should be considered to select the delivery method in thermal power construction business and develop a standard of selection of appropriate delivery method through questionnaire and interviews to establish a model to select the delivery method that fits the business goal of the subject of delivery. In the future, if the delivery method selection model suggested in this study is applied, it is expected to select the appropriate delivery method of power plant construction business by effectively reflecting the business goal, characteristics and demand of the delivery subject, and characteristics of the construction business apart from the existing customary practices that decided the delivery method dependent on the subjective and experience based judgement.

• Journal of the Korean earth science society
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• v.31 no.7
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• pp.720-737
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• 2010

This study is to analyze the temporal and spatial distributions of solar radiation in South Korea. Solar radiation data is observed every minute at 22 KMA (Korea Meteorological Administration) stations using pyranometer from January 2000 to August 2007. These data were calibrated using intensive comparative observation and solar radiation model. Intensive comparative observations are accomplished at 22 KMA stations between KNU (Kangnung (Gangneung-Wonju) National University) standard and station instruments during the month of August 2007. The solar radiation of a clear sky mainly is affected by precipitable water, solar altitude and geological height. Also old (raw) data is corrected by the solar radiation model only about clear day and is revised based on the temporal trend of instrument's sensitivity decrease. At all periods and all stations, differences between raw data (13.31 MJ/day) and corrected data (13.75 MJ/day) are 0.44 MJ/ day. So, the spatial distribution of solar radiation is calculated with seasonal and annual mean, and is the relationship with cloud amount is analyzed. The corrected data show a better consistency with the cloud amount than the old data.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.11
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• pp.128-134
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• 2016

Estimating the repair and reinforcement (R&R) costs for each bridge member is essential for managing the life cycle of a bridge using a bridge management system (BMS). Representative members of a bridge were defined in this study, and detailed and representative R&R methods for each one were drawn in order to develop a systematic maintenance cost model that is applicable to the BMS. The unit cost for each detailed R&R method was established using the standard of estimate and historical cost data, and a systematic procedure is presented using an integration program to enable easy renewal of the R&R unit cost. Also, the average unit cost of the representative R&R methods was calculated in the form of a weighted average by considering the unit cost and application frequency of each detained R&R method. The appropriateness of the drawn average unit cost was reviewed by comparing and verifying it with the previous historical unit cost. The suggested average R&R unit cost can be used to review the validity of the required budget or the appropriateness of the R&R performance cost in the stage to establish the bridge maintenance plan. The results of this study are expected to improve the reliability of maintenance cost information and the rationality of decision making.

• Fire Science and Engineering
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• v.34 no.1
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• pp.47-54
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• 2020

This paper proposes a solution to the problems of constructing and installing sway braces for existing standpipes in narrow spaces and pits. The study develops a floor-fixed sway brace for a narrow space that can support the ground area under horizontal seismic loads (X-axis, Y-axis) as well as vertical seismic loads (Z-axis). The results of structural analysis using SolidWorks simulation showed that the eccentric load was generated in the first design according to the anchored position along the vertical direction, and the problem of exceeding the allowable stress of the material along the horizontal and vertical directions. In the second design model, deformation caused by the eccentric load along the vertical direction, similar to the first design model, did not occur. The maximum strain rate was 0.17%, which is approximately 12.84% less than the first design model (Maximum strain rate of 13.01%). It was confirmed that the structural stability and durability improved. Compressive and tensile load testing of the prototypes showed that all of them meet the performance criteria of the standard.

• KDI Journal of Economic Policy
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• v.13 no.4
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• pp.141-153
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• 1991

The optimal choice of the tax rate and the inflation rate framework is extended to yield relevant interpretations for the optimal fiscal and monetary policy regime in Korea. To study the relationship between the government budget and monetary growth in different environments of policy coordination, two models assuming different degrees of fiscal dominance are developed. By modelling differing institutional arrangements of the fiscal and the monetary authority from an optimal government finance viewpoint, we find the optimal relationship among some important fiscal and monetary variables. By testing the existence of the relationship empirically, we find the characteristics of the optimal policy-mix regime in Korea. The first model-the strong from of fiscal dominance-studies the optimal collection of seigniorage in a period-by-period optimization with standard assumptions on the income velocity of money, deriving a general testable result: the optimal inflation/tax rate ratio co-vary with the marginal revenue ratio. The second model-the weak form of fiscal dominance-studies an implication of the inflationary bias of discretionary monetary policy in the presence of fiscal side distortions. This model shows that the tax rate and the inflation rate can have a positive correlation. Empirical tests of the theoretical results are done for the Korean economy for 1972-1989 period. The test results show that the macroeconomic policy regime in Korea can be characterized by the strong form of fiscal dominance, implying the importance of the government budget in explaining money growth and inflation.

• Journal of Korea Water Resources Association
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• v.44 no.12
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• pp.975-990
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• 2011

In this study, to develop an assessment method for spatio-temporal riverbed changes, a 1-dimensional model (HEC-RAS) and a 2-dimensional model (CCHE2D) were built and applied. As for the analysis of a riverbed's long-term change in a real stream, three new assessment methods were developed, which are called the "Sediment section cumulative curve", "Sediment section moment", and "Sediment probability distribution function." These methods were used to assess the characteristics of riverbed changes using a consistent valuation standard and to understand changes in quantities intuitively. From the results of this study, sediment characteristics of cross sections can be detected effectively by applying the "Sediment section cumulative curve" method to determine whether there is any sedimentation or erosion in total emission. The amount of sedimentation or erosion occurring in the right or left banks, which divided by center column, could be presented as one criterion by applying the "Sediment section moment" method. This approach could be utilized as an indicator for sediment predictions. Spatio-temporal sediment variables can be presented quantitatively by determining the mean and uncertain boundaries through the "Sediment probability distribution function", and finally, the results can be illustrated for each cross section to provide intuitive recognition.

• Journal of Wetlands Research
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• v.13 no.1
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• pp.79-94
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• 2011

As demonstrated in study for non-submerged groynes, the flow field is predominantly two-dimensional, with mainly horizontal eddies. The eddies shed form the tips of the groynes and migrate in the flow direction. These eddies have horizontal dimensions in the order of tens of meters and time-scales in the order of minutes. In the standard flow simulations, these motions are usually not resolved, due to a too coarse grid, too large time steps and, more importantly, the use of inadequate turbulence modelling. using for example a k-${\varepsilon}$ model, it is necessary to introduce substantial modifications. Therefore simulation resolved in this study, were carried out using the DELFT-3D-MOR programme, which is part of the DELFT3D software package of WL/Delft Hydraulics and In this study, apply a two-dimensional depth-averaged model, taking an horizontal large eddy simulation(HLES). The bed morphology computed when using HLES, as well as the associated time-scale, is similar to what has been obseved in a field case. When using a mean-flow model with-out HELS, the bed morphology is less realistic and the morphological time-scale is much larger. This slow development is the result of neglecting(or averaging). the strong velocity fluctuations associated with the time-varying eddy formation.

• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.7
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• pp.143-152
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• 2015

The 'Quality Competitiveness Index' (QCI) is defined as an quantitative and disinterested indicator that measures and compares the quality of products across the world. The purpose of this study is to suggest the 'Quality Competitiveness Assessment Model' (QCAM) and calculate QCI of a popular UHF RFID Label tag (Global ISO 18000-3C supported) available these days in a global apparel market. The model was based on KS-QEI(Korean Standard-Quality Excellence Index), and was composed with the following 4 evaluation categories, a process capability test, an environmental reliability test, a durability test and a design margin test. The QCI score can be calculated with the following formula, using the weighted arithmetic mean between a score of each evaluation category ($X_1$, $X_2$, $X_3$, $X_4$) and each weight($w_1$, $w_2$, $w_3$, $w_4$). The actual weights was determined by an result of AHP survey to which was conducted for the related Industry-University-Institute experts. The proposed index shows the results of comparisons with global competitor's products as well as the high-quality domestic RFID label tags. In addition, it will play an important role for manufacturers when developing their future products.

• The Journal of Society for e-Business Studies
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• v.23 no.3
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• pp.159-171
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• 2018

The imported foods, which are imported and sold domestically, are on the rise every year, and the scale is expected to be larger, including processing the imported raw materials. However, the origin of raw materials is indicated when declaring cargo for finished products of agricultural products, but the standardization of inspection information management system for raw materials is insufficient. In addition, there is a growing concern about the presence of residual pesticides or radioactivity in raw materials or products, and customer want to know production history information when purchasing agrifoods. It manages the hazard analysis of imported agricultural products, but most of them are global issues such as microorganisms, residual pesticides, food additives, and allergy components, etc. Therefore, it is necessary to share among the logistics entities in the entire transportation process the related data. Additionally, to do this, it needs to design an architecture and standardize business model. In this paper, it defines the architecture and the work-flow that occurs between the business process for collecting, processing, and processing information for tracking the status of imported agricultural products by steps, and develops XML message with UBL and the extracted conceptual information model. It will be easy to exchange and share information among the logistics entities through the defined standard model and it will be possible to establish visibility, reliability, safety, and freshness system for transportation of agricultural products requiring real-time management.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.11
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• pp.126-136
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• 2018

The purpose of this study was to develop a severity-adjustment model for predicting mortality in acute stroke patients using machine learning. Using the Korean National Hospital Discharge In-depth Injury Survey from 2006 to 2015, the study population with disease code I60-I63 (KCD 7) were extracted for further analysis. Three tools were used for the severity-adjustment of comorbidity: the Charlson Comorbidity Index (CCI), the Elixhauser comorbidity index (ECI), and the Clinical Classification Software (CCS). The severity-adjustment models for mortality prediction in patients with acute stroke were developed using logistic regression, decision tree, neural network, and support vector machine methods. The most common comorbid disease in stroke patients were hypertension, uncomplicated (43.8%) in the ECI, and essential hypertension (43.9%) in the CCS. Among the CCI, ECI, and CCS, CCS had the highest AUC value. CCS was confirmed as the best severity correction tool. In addition, the AUC values for variables of CCS including main diagnosis, gender, age, hospitalization route, and existence of surgery were 0.808 for the logistic regression analysis, 0.785 for the decision tree, 0.809 for the neural network and 0.830 for the support vector machine. Therefore, the best predictive power was achieved by the support vector machine technique. The results of this study can be used in the establishment of health policy in the future.