• IE interfaces
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• v.16 no.4
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• pp.507-514
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• 2003

In personal communication systems location management of mobile terminals is required to connect incoming calls to the mobile terminals. Investigation of effective location update and paging strategies is important to reduce the cost of location management. In this study, we propose a paging strategy considering the mobile terminals' residence patterns. The first paging area is characterized by the set of cells in the location area where mobile terminals usually stay for a significant period of time. The rest of cells in the location area are included into the second paging area. To reduce the paging cost the first paging area is decided by reflecting various residence patterns of mobile terminals. For an incoming call, the sequential paging is performed in the order of the paging area. Thus the paging cost is greatly reduced, especially when the called mobile terminal is located in the first paging area. The proposed strategy is expected to be more effective than an existing strategy that uses the anchor cell in the location area.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2003.05a
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• pp.425-432
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• 2003

In personal communication systems, location management of mobile terminals is required to connect incoming calls to the mobile terminals. Investigation of effective location update and paging strategies is important to reduce the cost of location management. In this study, we propose a paging strategy considering the mobile terminals' residence patterns. The first paging area is introduced, which is characterized by the set of cells in the location area where mobile terminals usually stay for a significant period of time. We propose the decision criterion of the first paging area by comparing the cost against zone-based strategy. For an incoming call. we perform the sequential paging by the order of the first paging area and the rest of cells in the location area called by the second paging area. Thus the paging cost is greatly reduced, especially when the called mobile terminal is located in the first paging area. The proposed strategy is expected to be more effective than existing strategy using anchor cell in the location area because it reflects various residence patterns of mobile terminals.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2005.11a
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• pp.229-234
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• 2005

The purpose of this study is to analyze a Characteristics of block formation and commercialization of residential books commercial area along urban arteries on Teheran-ro in Seoul. 'Teheran-ro' is selected as a case site to analyze the characteristics of residential blocks commercial area along urban arteries. The study analyzes the characteristics of the street network and block formation in commercial area along arteries and rear residential blocks, and commercialization of residential blocks commercial area along urban arteries according to the characteristics of street network and block formation. The analysis about block formation progress about i ) a street network and block formation, ii ) the scale of blocks, iii) division of lots, iv) lots system. The analysis about commercialization of residential blocks commercial area progress about i) a street network and block formation, ii) a density of building, iii) a use of building

• Korea Trade Review
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• v.44 no.4
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• pp.115-128
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• 2019

This article analyzes issues regarding the economic development of the arctic area with the aim of finding ways to help solve the problems and to support sustainable economic development of the arctic area. Some proposals are introduced for establishing a sound legal infrastructure of the Korea-Russia economic development of the arctic area. As Russia develops the Arctic area and the route through the Arctic area, Korea will gain the possibility of transportation efficiency, vitalization of international transaction, and finding new markets. Resource development in the North Pole is ongoing, with matching international transaction and economic benefits. To reflect the Korea-Russia interests and to sustain the effect, the legal infrastructure is inevitable. For example, it would be reinforced by pushing forward the Korea-Russia FTA. The legal infrastructure for economic cooperation of Korea and Russia has to reflect that 'the development of the Arctic area and making the route through the Arctic area' should increase the sustainability and vitality of international transaction. The legal infrastructure for economic benefits can also help mitigating non-economic arguments of international community such as the security risk in the Korean-peninsula and around the world.

• Journal of Photoscience
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• v.9 no.2
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• pp.400-402
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• 2002

We collected seeds of Solidago virgaurea plants growing at different altitudes on the Mt Hakusan area in Japan and cultivated them in a naturally-lit green house. Three-week-old seedlings were irradiated with supplemental UV-B for 12 h each day for 1 and 2 weeks. After a week of itradiation the seedlings of the population collected from the higher altitude at Oh-nanjiho (ON) had accumulated more anthocyanins than those from the lower altitude at Bettoh-deai (BD). Levels of anthocyanins in the ON seedlings were highly correlated with the dose of UV-B radiation and the correlation was also observed after 2 weeks. The growth of the third leaves was retarded by UV-B radiation in both populations. The extent of growth retardation in the third leaves was correlated with the dose of UV -B radiation in both populations. However, no significant difference in the extent of leaf area growth was observed between the ON and BD populations. The increase in plant fresh weight was extensively inhibited in the ON seedlings after 1 week of UV-B radiation. The inhibition was recovered to those in the BD population by 2 weeks irradiation. These results indicate that these populations respond differentially to supplementary UV -B radiation during the first week. Because flavonoids such as anthocyanins play an important role in protection against UV-B radiation in many plants, populations growing at higher altitude may be better able to adapt to increased global levels of UV-B radiation.

• Journal of the Korean Society of Marine Environment & Safety
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• v.17 no.4
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• pp.419-427
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• 2011

The characteristics for hydrogen production and the thermochemical properties of high temperature steam electrolysis(HTSE) device have been numerically analyzed in a two-dimension, steady-state with using the COMSOL $Multiphysics^{(R)}$. The main parameters for the calculation are applied voltage, ASR(Area-specific Resistance), temperature and pressure of the inlet gas flow. The results showed that thermal-neutral voltage was 1.2454 V and rather than the cell temperature increases or decreases with increasing applied voltage by thermal-neutral voltage starting this voltage the temperature in high voltage tended to rise and temperature in the low voltage tended to fall. And with, increasing the values of ASR, temperature inside the cell and the hydrogen production rate were decreased.

• Korean Journal of Remote Sensing
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• v.33 no.5_2
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• pp.641-645
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• 2017

This study was conducted to compare three agro-climatic indices among 22 agro-climatic zones in Northeast China area. Meteorological data produced by NASA (MERRA-2) was used to calculate growing degree days (GDD), frost free period (FFP), and growth season length (GSL) at this study sites. The three indices did not differ among 6 years (2011-2016). However, they showed statistical spatial difference among agro-climatic zones. The GDD ranged between $531.7^{\circ}C{\cdot}day$ (zone 22) and $1650.6^{\circ}C{\cdot}day$ (zone 1). The range of the FFP was from 141.5 day (zone 22) to 241.7 day (zone 1). And the GSL showed spatial distribution between 125.1 day (zone 22) and 217.9 day (zone 1).

• The Journal of Engineering Geology
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• v.26 no.1
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• pp.1-13
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• 2016

Groundwater flow paths and groundwater ages at a radioactive waste repository located in a coastal area of South Korea were evaluated using the hydrochemical and hydrogeological characteristics of groundwater, surface water, rain water, and seawater, as well as by numerical modeling. The average groundwater travel time in the top layer of the model, evaluated by numerical modeling and groundwater age (34 years), approximately corresponds to the groundwater age obtained by chlorofluorocarbon (CFC)-12 analysis (26-34 years). The data suggest that the groundwater in wells in the study area originated up-gradient at distances of 140-230 m. Results of CFC analyses, along with seasonal variations in the δ¹⁸O and δD values of groundwater and the relationships between ²²²Rn concentrations and δ¹⁸O values and between ²²²Rn concentrations and δD values, indicate that groundwater recharge occurs in the summer rainy season and discharge occurs in the winter dry season. Additionally, a linear relationship between dissolved SiO₂ concentrations and groundwater ages indicates that natural mineralization is affected by the dilution of groundwater recharge in the rainy summer season.

• Journal of Environmental Science International
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• v.5 no.3
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• pp.253-263
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• 1996

This study is an attempt to classify climatic regions of Korea based on the data of sunshine duration and to clarify the characteristics of sunshine for each divided regions. The data used in this study are the mean values of monthly and ten-daily sunshine duration, sunshine percentage, solar radiation and proud amount obtained from 63 weather stations of the Korea Meteorological Administration during the period of 1974~ 1993. The characteristics of annual change of sunshine percentage, annual duration of sunshine, percentage of sunshine, annual radiation, amount of cloud, days of sunshine percentage above 80% and-days of sunless are investigated by the mean values of -the stations belong to divided regions. The ward method of hierarchical cluster analysis is adopted to the analysis of data for the regional division. The results obtained in this study are summarized as follows. (1) The sunshine regions of Korea can be divided into six regions of the central west, central east, south west, souls east, Ullung-do and Cheju-do. These are strongly affected by the dirtribution of inclined slopes taking account of the topographic characteristics of Korea. (2) Annual distribution shows the sunshine duration of 1777~ 2287 hours, sunshine percentage of 40~53%, solar radiation of 3469~4637 MJ/$m^2$, cloud amount of 5.0~6.1, days of sunshine perrentage above 80% of 53~116days and sunless days of 46~71days. (3) The types of annual change of sunshine percentages is classified with four types of minimum in July and maximum in October, minimum in July and maximum in December, high in May and October and low in July and January, high in May and November and low in June and January. (4) The long-term trend of sunshine duration decrease in peninsula area but increase in island area and the Tong-term inclination of cloud amount is almost zero. The author believe this tendency is related to a pollutional turbidity than a cloud amount in inland area.

• Journal of Environmental Science International
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• v.19 no.8
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• pp.983-999
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• 2010

Wind power energy is one of the favorable and fast growing renewable energies. It is most important for exact analysis of wind to evaluate and forecast the wind power energy. The purpose of this study is to improve the performance of numerical atmospheric model by data assimilation over a complex coastal area. The benefit of the profiler is its high temporal resolution and dense observation data at the lower troposphere. Three wind profiler sites used in this study are inhomogeneously situated near south-western coastal area of Korean Peninsula. The method of the data assimilation for using the profiler to the model simulation is the three-dimensional variational data assimilation (3DVAR). The experiment of two cases, with/without assimilation, were conducted for how to effect on model results with wind profiler data. It was found that the assimilated case shows the more reasonable results than the other case compared with vertical observation and surface Automatic Weather Station(AWS) data. Although the effect of sonde data was better than profiler at a higher altitude, the profiler data improves the model performance at lower atmosphere. Comparison with the results of 4 June and 5 June suggests that the efficiency with hourly assimilated profiler data is strongly influenced by synoptic conditions. The reduction rate of Normalized Mean Error(NME), mean bias normalized by averaged wind speed of observation, on 4 June was 28% which was larger than 13% of 5 June. In order to examine the difference in wind power energy, the wind power density(WPD) was calculated and compared.