• Geophysics and Geophysical Exploration
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• v.15 no.3
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• pp.144-149
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• 2012

Korea Polar Research Institute (KOPRI) has successfully installed two autonomous very broadband three-component seismic stations at the King George Island (KGI), Antarctica, during the 24th KOPRI Antarctic Summer Expedition (2010 ~ 2011). The seismic observation system is originally designed by the Incorporated Research Institutions for Seismology Program for Array Seismic Studies of the Continental Lithosphere Instrument Center, which is fully compatible with the Polar Earth Observing Network seismic system. The installation is to achieve the following major goals: 1. Monitoring local earthquakes and icequakes in and around the KGI, 2. Validating the robustness of seismic system operation under harsh environment. For further intensive studies, we plan to move and install them adding a couple more stations at ice shelf system, e.g., Larsen Ice Shelf System, Antarctica, in 2013 to figure out ice dynamics and physical interaction between lithosphere and cryosphere. In this article, we evaluate seismic station performance and characteristics by examining ambient noise, and provide operational system information such as frequency response and State-Of-Health information.

• Journal of the Korean Society for Railway
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• v.18 no.6
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• pp.630-638
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• 2015

The total number of passengers on the KTX since its construction in 2004 surpassed 500 million in October, 2015. The operation of KTX made it possible to reach anywhere in a country in half a day, which subsequently altered people's lifestyle. As the KTX has become an important mode of transportation, there is a growing interest in the optimal size and location of its stations. Currently, the stations are constructed through public-private partnerships since a sufficient amount of budget is hard to secure only from the public sector; however, because railway stations are traditionally aimed at promoting public interests, an emphasis on the profitability of the private sector could compromise public interests. At this juncture, this study separately computes the number of users based on each of the two primary functions of the stations-as a railway station and as a sales facility-and estimates the numbers of people according to various transportation modes that are taken to access the stations. This estimation is applied to the case of Dongdaegu Station, which will open in 2016. Such an application helps to predict and respond to possible congestion as brought about by the expansion of the sales facility.

• Journal of Advanced Navigation Technology
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• v.23 no.2
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• pp.151-157
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• 2019

In geostationary satellite communications, which are widely used for broadcasting and communication, there is a path loss where the signal power on the path is largely reduced. It is important to consider rain attenuation when calculating link budget because the Ka band frequency is vulnerable to rain attenuation. In this study, rainfall trends were analyzed by using rainfall data from the year 2000 in four regions of Korea (Seoul, Incheon, Busan, Jeju) and the rainfall attenuation was calculated. This was used to analyse the satellite link budget and receiving performance for the down-link of the korea satellite COMS. In this study, the calculated G/T for the rainfall intensity of 0.5% per year using the rainfall data for 18 years increased by approximately $8.5dBK^{-1}$ compared to the ITU's zone-K rain model, and decreased by approximately $1dBK^{-1}$ compared to the precipitation data for 13 years from the TTA(Korea Telecommunications Technology Association). The results of this study can be used for the design of G/T in domestic-installed satellite ground station.

• Journal of Korean Tunnelling and Underground Space Association
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• v.23 no.5
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• pp.339-357
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• 2021

As the construction of trans infrastructure using the underground tunnel have been rapidly increased, various nearby excavation of existed underground facility including subway structure has been occurred in urban tunnelling. The concern and worry relating to the safety and stability of the existed facility by nearby excavation is becoming the key issues in urban tunnelling. In this study, it was conducted for existed the subway station structure at Seoul subway line which was closely located in the new Dongbuk urban metro railway to determine the behavior characteristics of station structure according to adjacent tunnel construction. Also, it was reviewed the evaluation of the safety zone and excavation method for subway structure. And after a review of damage evaluation, track irregularities and structural calculation by using a numerical analysis, stability of the subway structure according to nearby tunnel excavation was evaluated to be secured. This study is expected to be applied as useful reference in advance if you need to review the effects of existed structure according to nearby construction in complex urban tunnelling.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.29 no.1
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• pp.84-88
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• 1984

To obtain basic information on the breeding of early maturing, short plant height rapeseed varieties, the following 7 varieties, Isuzu, Miyuki, Norin 25, Rang, Yongdang, Cresus and Tower were used in diallel crosses in 1979. Maturing date, plant height and grain weight per plant for the parents, $F_1$'s and $F_2$'s of the 7 x 7 partial diallel crosses were measured in 1981 for analysis of their genetic behavior. The results obtained are summarized as follows: 1. The days to maturing of $F_1$'s showed complete dominance for early maturing, and both additive and dominance genetic variances were significant. Number of effective factors in $F_1$'s was 3, but in $F_2$'s was 1. The degree of dominance in $F_1$'s was partial, while in $F_2$'s was complete. Both broad and narrow sense herita-bilities in $F_1$'s was high, while in $F_2$'s was low. 2. Yield per plant in $F_2$'s was controlled by additive component of genetic variance only, but $F_1$'s was different. The degree of dominance in $F_1$'s was complete, while in $F_2$'s was partial. The direction of dominance showed almost complete dominance over high yield and three effective factors was estimated. Yield per plant was controlled by recessive genes. 3. The plant height was controlled by both dominance and additive variance. Dominance was directed toward tall plant height. Number of effective factors was 2, and broad and narrow sense heritability were high in the plant height.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.1
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• pp.23-30
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• 1993

This study was conducted to obtain the fundamental information on antioxidant component as affected by process of grain filling in different plant types of sesame. Sesamin and sesamolin as antioxidant components, oil content and seed weight were investigated for two plant types with different by branching habit. The sesamin and sesamolin contents in grains followed a pattern of increase immediately after flowering in branch type and monocapsule habit than non-branch type and tricapsule habit. But they started to decrease around 45 days after flowering, which oil content and seed weight continued to increase until maturity. The sesamin content increased quickly up from 10th to 40th day after flowering and showed almost maximum at 43th day after flowering. The sesamolin content increased quickly up from 20th to 30th day after flowering and showed almost maximum at 45th day after flowering. The oil content increased quickly up from 20th to 30th day after flowering and showed almost maximum at 47th day after flowering. The seed weight increased quickly up from 20th to 40th day after flowering and showed almost maximum at 48th day. The sesamin content, sesamolin content, oil content and seed weight showed almost maximum at from 43th to 48th day after flowering. So that this period was considered to be of physiological maturity.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.2B
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• pp.219-231
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• 2010

The Reference Evapotranspiration Calculator Software (REF-ET) supports computational guidelines for the reference evapotranspiration using seventeen FAO Penman-Monteith (PM) equations simultaneously such as the ASCE and FAO standardized forms. The REF-ET can conveniently consider missing data predictions and regional site characterizations, when reference ET is computed on monthly, daily, and hourly time steps. The applicability of the REF-ET was estimated to simulate the reference ET using hourly weather data from Seoul weather station for 29 years. The result found that the FAO24-Rd and 1957-Makk equations closely concerned with solar radiation parameter which were the most highly correlated to reference ET computed by pan coefficient. In addition, the 1957-Makk equation was identified as the most correct computational method for reference ET by analysis of bias and root mean square error. The 1957-Makk equation could predict the reference ET within the error of less than 1.06 mm/day, though all the other equations tended toward overestimation of predicting the reference ET in comparison with refecence ET of pan. The results of this study suggest that the REF-ET will be applicable to support reference ET estimation for a variety of field condition and time-scale.

• Spatial Information Research
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• v.18 no.5
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• pp.1-11
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• 2010

Since January 2009, Seoul Metro Government(SMG) is operating own Network RTK Systems connecting four(4) GNSS Reference Stations which are installed inside Seoul Metro City area. SMG is currently providing VRS data service via wireless internet for Network-RTK and RINEX data observed from GNSS Reference Stations. This paper will discuss utilization of data available from SMG Network-RTK System for various applications, and present the test results on practicalities of Virtual RINEX data. For the utilization of data available from SMG Network- RTK system, 1)NTRIP data delivery of GNSS realtime observables streaming and converting to RINEX at receiving side, 2) monitoring deformation of bulky structures using GNSS observation were discussed. In addition to those discussion, 3) broadcasting VRS correction data for job site via radio modem after acquiring such correction data on-line using NTRIP based GNSS Internet Radio from SMG Network-RTK System were introduced. For the test results on practicalities of Virtual RINEX data, 1) the post-processing results of the GNSS observation data on a certain point with GNSS Reference Station data have been compared to the post-processing results of Virtual RINEX data on the same point generated from SMG Network-RTK System, and 2) VRS RTK positioning results for a certain point and post-processing results of Virtual RINEX data for the point were compared. The results showed only a few mm difference, and the high possibility for using Virtual RINEX data for post-processing applications.

• Journal of Korean Society of Forest Science
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• v.77 no.4
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• pp.401-413
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• 1988

To investigate the users' activity, impact and psychology in Naejang Temple district at Mt. Naejang National Park in Korea, users' density and questionnaire survey at three major picnic areas and passenger counting at major pass were executed and environmental impacton on the site was surveyed. The total number of visitors showed stability at the level of one million persons every year after 1984. Users' impact was much severe along the main trail, the upper cablecar station and the slope from the observatory to Keumsun Valley, The maximum momentary number of users was estimated as 53,000 persons in autumn. Approximately 20% of the total number of visitor used Keumsun Valley and Weonjeok Valley area and 80% of visitors left after using only grassland and cablecar. The visitors' characteristics was similiar to the type of long-distanced national park and the main visiting purpose was to see autumn leaves. The psychological satisfaction did not very significantly as to increasing user's speace. As a result of varimax rotated factor analysis, the 1st factor, most affecting users' psychological satisfaction, was related to landscape and consisted of nature disturbance, crowdedness, noisiness, cleanness, in order of importance. The 2nd factor was related to facilities and consisted of number of toilet, number of waste-baskets, amount of drinking water, safety, in order of importance.

• Journal of the Korean Wood Science and Technology
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• v.10 no.2
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• pp.3-11
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• 1982

In order to investigate the annual mean equilibrium moisture content(EMC), the equilibrium moisture content investigated were the desorbed and adsorbed equilibrium moisture content with two end-matched samples for red pine (Pinus densiflora S. et Z.), Douglas fir (Pseadotsuga menziesii Franco), oak (Quercus mongolica Fischer) and red lauan (Shorea spp.) in instrument screen at forest experiment station located in Seoul, Chuncheon, Daejeon, Kyungju, Jinju and Gwangju area for four years (1970. 1 - 1973. 12). The results summarized were as follows. 1. The annual mean desorbed equilibrium moisture content of red pine, Douglar fir, oak and red lauan were 14.8, 13.7, 14.0 and 14.2 percent respectively and higher than the annual mean adsorbed equilibrium moisture content of those species. 2. The annual mean desorbed - and adsorbed equilibrium moisture content in central areas (Seoul, Chuncheon, Daejeon) were higher than those in southern areas (Kyungju, Jinju, Gwangju). 3. On the whole, the monthly mean desorbed - and adsorbed equilibrium moisture content were lowest in April and highest in August though difference of month in areas. 4. Average and range of annual national equilibrium moisture content was 12.3 ~ 14.2 ~ 15.7 percent for desorbed equilibrium moisture content and 11.3 ~ 13.2 ~ 14.7 percent for adsorbed equilibrium moisture content and 12.0 ~ 14.1 ~ 16.4 percent for calculated equilibrium moisture content based on tempera ture and humidity.