• The Transactions of the Korean Institute of Electrical Engineers A
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• v.51 no.1
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• pp.29-36
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• 2002

It is required that the current state of system should be Precisely monitored for efficient and safe operation of the subway power system and it is an important Problem to secure the high quality data for state estimation. The current state of subway power system is estimated by using data transmitted to control center from every measuring instrument. The high accuracy and trust can be maintained if the measured data have a high quality. But it is difficult to estimate the accurate state of system because of the noises in transmitted data and the inaccuracy of measuring instruments. So the object is to reduce the difference between the real values and the measured values in order to improve considerably the inaccuracy due to Instrumental errors and transmission noises using the state estimation method. In this paper, we proposes a new state estimation to estimate the accurate state of the subway power system from the measured values of a Sang-In station in Daegu subway and consider the possibility of application to the real subway power system. on the basis of that. The simulation results show to make sure of the possibility to apply to the real system usefully.

• Korean Journal of Remote Sensing
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• v.38 no.6_1
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• pp.1301-1314
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• 2022

Normalized Difference Vegetation Index (NDVI) is utilized as an indicator to represent the vegetation condition on the land surface in various applications such as land cover, crop yield, agricultural drought, soil moisture, and forest disaster. However, satellite optical sensors for visible and infrared rays cannot see through the clouds, so the NDVI of the cloud pixel is not a valid value for the land surface. This study proposed a real-time correction of the underestimation noise for GEO-KOMPSAT-2A (GK2A) daily NDVI and made sure its feasibility through the quantitative comparisons with Moderate Resolution Imaging Spectroradiometer (MODIS) NDVI and the qualitative interpretation of time-series changes. The underestimation noise was effectively corrected by the procedures such as the time-series correction considering vegetation phenology, the outlier removal using long-term climatology, and the gap filling using rigorous statistical methods. The correlation with MODIS NDVI was higher, and the difference was lower, showing a 32.7% improvement compared to the original NDVI product. The proposed method has an extensibility for use in other satellite products with some modification.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2010.04a
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• pp.173-174
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• 2010

As the quantity of goods transported, port industry and inland transport industry have developing to transport 630million ton goods annually. And the inland transport industry consists of ground transport for almost 80% of total transported goods. But, ground transport causes some serious problems especially the emission of greenhouse gases from trucks. According to issue "global warming", many regulations and agreements with countries in the world are becoming necessary and it is being fulfilled now. It is sure that Korea will have duty to reduce CO2 emission from 2013. Thus inland transport must cut off CO2 emission level. Therefore this paper will address that the calculation of CO2 emission under route of transportation container from six major container ports in Korea. And then, it will predict CO2 emission of inland transport industry according to increasing container traffic rate at ports.

• Proceedings of the KIEE Conference
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• 2000.11a
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• pp.129-131
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• 2000

We must precisely understand the current state of system for efficiently and safely operating the power system of subway and it is the important problem to secure the high-quality data for state estimation. The current state of subway system is calculated by data to be transmitted to central control office from every place to install the measuring instruments so the high accuracy and trust can be maintained if the measured data have a high quality. But it is difficult to estimate the accurate state of system because of the noises in transit data and the inaccuracy due to errors of measuring instruments. So the object is to reduce the difference from the real value in terms of improving considerably the inaccuracy due to instrumental errors and noises using the state estimation method. In this paper we estimate the accurate state of the subway power system in the arbitrary measured values of a Sangin station in Deagu subway, and consider the possibility to apply to the real subway power system on the basis of that. This test shows to make sure of the possibility to apply to the real system usefully.

• Journal of the Korean Society of Safety
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• v.25 no.6
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• pp.47-52
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• 2010

Many industrial accidents have occurred over the years in the manufacturing and construction industries in Korea. However, as the service industry has increased continuously, the share of the accident rate in the service industry was 39.07% in 2009, while the manufacturing industry share was 33.73%. The service industry share overtook the manufacturing industry share for the first time. Therefore, this research considers prevention of industrial accidents in the service industry as well as manufacturing and construction industries. This paper describes a procedure and a method to estimate efficient accident rate forecasting and estimated zero accident time in the service industry in order to prevent industrial accidents in the transportation, storage, and telecommunication divisions. This paper proposes a model using an analytical function for the sake of very efficient accident rate forecasting. Accordingly, this paper has develops a program for accident rate forecasting, zero accident time estimating, and calculation of achievement probability through MFC (Microsoft Foundation Class) software Visual Studio 2008 in the transportation, storage, and telecommunication divisions. In results of this paper, ARIMA (Auto Regressive Integrating Moving Average) is regarded as a very efficient forecasting model for the transportation, storage, and telecommunication division. In testing this model, value minimizing the Sum of Square Errors (SSE) was calculated as 0.2532. Finally the results of this paper are sure to help establish easy accident rate forecasting and strategy or method of zero accident time in the service industry for prevention of industrial accidents.

• Conservation Science in Museum
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• v.4
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• pp.23-32
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• 2003

As the kettle excavated from a site in Hwangnam-dong, Gyeongju was presumed to have been used as a melting crucible in a glass production workplace, we decided to prove its usage by scientific analysis. First, we performed conservation treatment to find the original status of the kettle, and then SEM-EDS and XRD analysis of the five corrosions created on the surface of the kettle. The fragment of the spout, which played a crucial role for the kettle to be considered as a melting crucible, was discovered during the conservation treatment. So the mouth rim of the kettle was restored to perfection. When we observed the microstructure of the metal sample, it was proved to be cast iron gradually cooled without heat treatment. In the corrosion products, the main components were Fe and O and other components such as P, Si, Ca, and S were found. The main compounds were quartz, vivianite, goetheite, akaganite, lepidocrocite, hematite, etc. Although these components were used as raw materials for making glass, these were found not in the melting status but mere raw materials. This can be an evidence to show these site where the kettle was excavated had been a glass production workplace. However, it is not sure that the kettle was used as a melting crucible. Moreover, if we consider the organic mold and sand clay accumulated in the well site when the kettle was excavated at first, we can see this as a formative factor of the corrosions of the kettle. Therefore, we concluded that the kettle is a typical cast iron and was not used as a melting crucible of glass.

• Economic and Environmental Geology
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• v.39 no.3 s.178
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• pp.285-299
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• 2006

The Mireuksaji stone pagoda in Iksan is the largest stone pagoda existing in Eastern Asia. It was assumed that originally it had been established in the shape of nine-storied pagoda but as time went by only six-storied pagoda remained partially due to collapsing, repair and reconstruction. According to the reference, we can't make sure when its modification happened. The form that the pagoda is having now, was modified with concrete by the Japanese during the 1910s. The materials mixed in concrete were mixture of Portland cement, all sorts of stone, sand, and a little bit of new building stone, additive and compound. And also these materials were applied to cultural assets without any experiment at the time of 1910s as maintenance, which are still used recently. To prevent the change of its shape, the west side, south side and the north side which is partially destructed was rebuilt and reinforced with concrete and some of the deformed parts were also filled. The amounts of concrete used were about 200 tons. Such method had prevented the pagoda from destructing, however, by choosing a wrong repair method, its surface of the stone has secondary contaminants and precipitation caused by concrete. This kind of contamination speeds up the weathering which accelerates the aging mechanism of the stone to make it even harder to revive the absence of historical nature. Therefore, we are to find the best cleaning method to remove the secondary hazard contaminants.

• Journal of the Korean association of regional geographers
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• v.9 no.4
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• pp.576-591
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• 2003

This study examined how historical facts of the past were established as a symbol or identity of a region and reorganized in the present local communities. Janseong has reorganized regional symbols through a regional festival named Hong-gil-dong Festival based on its tradition and cultural resources and used them as a strategy for the regional revitalization. Jangseong was known as "a district of noble scholars" represented by the Philam Seowon(local school) enshrining Kim In-hoo, a superior one of the Confusion scholars of Joseon period. And it was considered as "a place of justice" because of historical fact that it was an important base of Donghak movement and the struggle by righteous soldiers who fought for the country in the late Joseon period. Moreover, as the place which is assumed as a birthplace of Hong Gil-dong, a hero of the Hong Gil-dong story was excavated, the local government has reorganized Mr. Hong as a symbol of the region and has held the Hong Gil-dong festival for its development. In spite of its short history, the festival was established as a representative of Janseong. It also created various regional cultural attractions such as regional logos of Hong Gil-dong and a tourist attraction of his birthplace. Jangseong reorganized its tradition for the regional revitalization through a business-oriented property of the event strategy enforcing a dynamic and external image. In the aspects of tradition reorganization and use for actual development, it is sure that the Hong Gil-dong Festival will work for true integration and revitalization of the region by providing experiences of reorganized regional tradition and culture along with various regional landscapes.

• Journal of the Korean Association of Geographic Information Studies
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• v.15 no.1
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• pp.43-51
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• 2012

The OLS(ordinary least squares) method is widely used in hedonic housing models. One of the assumptions of the OLS is an independent and uniform distribution of the disturbance term. This assumption can be violated when the spatial autocorrelation exists, which in turn leads to undesirable estimate results. An alterative to this, spatial econometric models have been introduced in housing price studies. This paper describes the comparisons between OLS and spatial econometric models using housing transaction prices of Busan, Korea. Owing to the approaches reflecting spatial autocorrelation, the spatial econometric models showed some superiority to the traditional OLS in terms of log likelihood and sigma square(${\sigma}^2$). Among the spatial models, the SAR(Spatial Autoregressive Models) seemed more appropriate than the SAC(General Spatial Models) and the SEM(Spatial Errors Models) for Busan housing markets. We can make sure the spatial effects on housing prices, and the reconstruction plans have strong impacts on the transaction prices. Selecting a suitable spatial model will play an important role in the housing policy of the government.

• The Korean Journal of Nuclear Medicine
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• v.30 no.1
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• pp.77-85
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• 1996

Radioiodine($^{131}I$) has been used for the treatment of Graves' hyperthyroidism since the late 1940's and is now generally regarded as the treatment of choice for Graves' hyperthyroidism who does not remit following a course of antithyroid drugs. But for the dose given, several different protocols have been described by different centers, each attempting to reduce the incidence of long-term hypothyroidism while maintaining an acceptable rate control of Graves' hyperthyroidism. Our goals were to evaluate effective half-life and predict absorbed dose in Graves' hyperthyroidism patients, therefore, to calculate and readminister radioiodine activity needed to achieve aimed radiation dose. Our data showed that the mean effective $^{131}I$ half-life for Graves' disease is 5.3 days(S.D=0.88) and mean biologic half-life is 21 days, range 9.5-67.2 days. The mean admininistered activity and the mean values of absorbed doses were 532 MBq(S.D.=254), 112 Gy (S.D.=50.9), respectively. The mean activity needed to achieve aimed radiation dose were 51MBq and marked differences of $^{131}I$ thyroidal uptake between tracer and therapy ocurred in our study. We are sure that the dose calculation method that uses 5 days thyroidal $^{131}I$ uptake measurements after tracer and therapy dose, provides sufficient data about the effective half-life and absorbed dose of $^{131}I$ in the thyroid and predict the effectiveness of $^{131}I$ treatment in Graves' hyperthyroidism.