• Journal of the Korea Society of Computer and Information
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• v.17 no.12
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• pp.61-69
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• 2012

This paper shows results of the precise time comparison technique based on GPS code transfer in order to determine the UTC(Universal Time Coordinated) and generate TAI(International Atomic Time). CGGTTS(CCTF Group on GNSS Time Transfer Standards) which is generated by GPS timing receivers is used as the international standard format. For geodetic receivers which provide RINEX formats as GPS time transfer results, ROB(Royal Observatory of Belgium) developed a conversion program, r2cggtts, and have distributed the program to timing laboratories participating in TAI link all over the world. Timing laboratories generate the time comparison results of GPS code transfer by the program and send them to BIPM(Bureau International des Poids et Mesures) periodically. In this paper, we introduce the delay features generated while GPS code is transferred and the calibration methods of them. Then, we introduce the tropospheric delay and analyze the results of Saastamoinen model and NATO(North Atlantic Treaty organization) model. Saastamoinen model is the representative tropospheric zenith path delay model and NATO model is applied to the legacy r2cggtts program.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.40 no.4
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• pp.315-324
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• 2022

The conventional LESS (LEast-Squares Solution) is calculated under the assumption that there is no errors in independent variables. However, the coordinates of a point, either from traditional ground surveying such as slant distances, horizontal and/or vertical angles, or GNSS (Global Navigation Satellite System) positioning, cannot be determined independently (and the components are correlated each other). Therefore, the TLS (Total Least Squares) adjustment should be applied for all applications related to the coordinates. Many approaches were suggested in order to solve this problem, resulting in equivalent solutions except some restrictions. In this study, we calculated the normal vector of the 3D plane determined by the trace of the VLBI targets based on TLS within GHM (Gauss-Helmert Model). Another numerical test was conducted for the estimation of the Helmert transformation parameters. Since the errors in the horizontal components are very small compared to the radius of the circle, the final estimates are almost identical. However, the estimated variance components are significantly reduced as well as show a different characteristic depending on the target location. The Helmert transformation parameters are estimated more precisely compared to the conventional LESS case. Furthermore, the residuals can be predicted on both reference frames with much smaller magnitude (in absolute sense).

• Journal of the Korean association of regional geographers
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• v.14 no.5
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• pp.453-465
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• 2008

The purpose of this study is to introduce the concept of the geographic center, to examine its value as locational resource, and to consider the way of its practical uses. Geographic center is the intersection point where central meridian and central parallel cross each other. This geographic locational resources can be used as data for locational education in geographic education, the standards for antipodes, datum points for geodetic surveying, a factor of place marketing, etc. This study can be a model for a geographic discovery that is to seek many geographic resources being scattered about our country.

• Journal of the Korean earth science society
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• v.21 no.3
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• pp.315-322
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• 2000

In this study, the data used for the models were a set of 56 geologic estimates of long-term fault slip rates. The hest models were those in which mantle drag was convergent on the Transverse Ranges in the San Andreas fault system, and faults had a low friction (${\mu}$= 0.3). It is clearly important to decide whether these cases of low strength are local anomalies or whether they are representative. Furthermore, it would be helpful to determine fault strength in as many tectonic settings as possible. Analysis of data was considered by unsuspected sources of pore pressure, or even to question the relevance of the friction law. To contribute to the solution of this problem, three attempts were tried to apply finite element method that would permit computational experiments with different hypothesized fault rheologies. The computed model has an assumed rheology and plate tectonic boundary conditions, and produces predictions of present surface velocity, strain rate, and stress. The results of model will be acceptably close to reality in its predictions of mean fault slip rates, stress directions and geodetic data. This study suggests some implications of the thermoelastic characteristics to interpret the relationship with very low strength of San Andreas fault system.

• Korean Journal of Acupuncture
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• v.24 no.1
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• pp.65-77
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• 2007

목 적 : 본 연구(硏究)는 수소양삼초경근(手少陽三焦頸筋)의 이론적(理綸的) 근거(根據)를 해부학적(解剖學的)으로 제공(提供)하고 임상(臨床)에 경근(經筋)의 정확(正確)한 적용(適用)을 위함이다. 방 법 : Cadaver에 경근(經筋)을 표시(表示)하고 각각(各各)의경 경혈부위(經穴部位)에 표식(標識)와 pore 작업을 수행하고 각 경혈부(經穴部)를 피부(皮膚), 근막(筋膜), 그리고 근육(筋肉)의 천층(淺層), 중문층(中問層), 그리고 심층부(深層部)를 순서적(順序的)으로 해부(解剖)하여 근육(筋肉), 신경(神經), 혈관(血管) 등을 관찰(觀察)한다. 결 과 및 결 론 : 수소양삼초경근(手少陽三焦經筋)의 해부학적(解剖學的) 고찰(考察) 결과(結果)는 다음과 같다. 1) 근(筋) 육(肉) : 천층에 근막(TE1), 근막확장대(TE2), 근막과 근간결합(TE3), 근막과 신근지대(TE4), 근막과총지신근건(TE5), 근막및 총지신근과 소지신근간(TE6), 근막과 소지신근(TE7), 총지신근(TE8), 척측수근신근과 소지신근간(TE9), 상완삼두근건(TE10, 11), 상완삼두근(TE12), 삼각근(TE13), 삼각근및 극하근과 극상근간(TE14). 승모근(TE15), 흉쇄유돌근(TE-16, 17, 18), 후이개근(TE19, 22), 상이개근(TE20), 전이개근및 이하선근막(TE21), 안륜근(TE23), 중층에 소지신근건과 총지신근건간(TE4), 측두근막과 측두근(TE2O, 22, 23), 심층에 배측골간근(TE3), 시지신근과 골간막(TE5) 장모지신근(TE6), 시지신근(TE7), 장지신근과 장모지외전근간(TE8, 9), 상완삼두근(TE13), 견갑거근(TE15), 두판상근(TE16), 경상설골근과 하악이복근간(TE17) , 이복근(TE18) .2) 신(神) 경(經) : 천층에 척골신경의 배측지(TE1, 2, 3), 후전완피신경(TE4, 5, 6, 8, 9, 10, 11), 내측전완피신경(TE5, 6, 7, 8, 9, 10, 11), 후상완피신경(TE12, 13), 상외측상완피신경(TE13), 외측쇄골상신경(TE14, 15),대이개신경(TE16, 17, 18, 19), 소후두신경(TE19, 20), 이개측두신경(TE20, 21, 22), 안면신경측두지(TE22, 23), 관골측두신경(TE23), 중층에 견갑상신경(TE15), 견갑배신경(TE15), 경상설골근신경(TE17), 후이개신경(TE18, 19, 20), 안면신경측두지(TE20, 21, 22), 심층에 후골간신경(TE5, 6, 7), 요골신경심지(TE8, 9, 12, 13), 견갑상신경(TE14), 액와신경가지(TE14), 부신경(TE16), 안면신경과 부신경가지(TE17), 설인신경(TE17), 설하신경(TE17), 경신경고리(TE17), 미주신경(TE17), 안면신경 (TE18). 3) 혈(血) 관(管) : 천층에 척측정맥배측지(TE1, 2), 고유수장지동맥배측지(TE1), 배측중수골동맥배측지(TE2), 배측중수골정맥(TE3), 척측피정맥(TE4, 5, 6, 7, 8, 9, 10, 11), 배측정맥궁(TE4), 부요측피정맥(TE6, 8, 9),요측피정맥(TE10, 11), 후견봉정맥가지(TE13, 14), 후이개동 ${\cdot}$ 정맥(TE16, 17, 18, 19, 20), 전이개동 ${\cdot}$ 정맥(TE20), 천측두동 ${\cdot}$ 정맥(TE22, 23), 중층에 후상완회선동맥(TE14), 견갑배동맥(TE15), 견갑상동맥(TE15),천측두동 ${\cdot}$ 정맥(TE21), 관골측두동 ${\cdot}$ 정맥(TE23), 심층에 배측중수골동맥(TE3), 배측수근동맥궁(TE4), 후골간동맥(TE4, 5, 6, 7, 8, 9), 전골간동맥(TE6, 7, 9), 심상완동맥(TE10, 11), 상완동맥측부지(TE10, 11), 중간 측부동맥(TE12), 요측측부동맥(TE12), 심상완동맥가지(TE13), 후상완회선동맥(TE13), 견갑상동맥(TE14), 후두동 ${\cdot}$ 정맥(TE16, 17), 내경정맥(TE17). 결 론 : 1. 수소양삼초경근(手少陽三焦經筋)은 근육(筋肉), 그리고 관련(關聯) 신경(神經), 혈관(血管)으로 구성된다. 2. 본 연구(硏究)는 경근(經筋)에 관한 기존(旣存)의 연구(硏究)와 비교(比較)하여 볼 때에 경근(經筋)의 구성요소(構成要素)에 있어서 약간(若干)의 차이(差異)를 보여준다. 3. 해부학적(解剖學的) 연구결동(硏究結東), 경근(經筋) 근육(筋肉)을 지배(支配)하는 신경(神經)${\cdot}$혈관(血管)의 개념(槪念)과 경근(經筋)을 스쳐 지나가는 신경(神經)${\cdot}$혈관(血管)의 개념(槪念)은 구분(區分)된다.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.34 no.3
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• pp.299-308
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• 2016

Various space geodetic techniques have been developed for highly precise and cost-efficient positioning solutions. By correcting the physical phenomena near the earth’s surface, the positioning accuracy can be further improved. In this study, the vertical crustal deformation induced by the ocean tide loading was accurately estimated through GNSS absolute and relative positioning, respectively, and the tidal constituents of the results were then analyzed. In order to validate the processing accuracy, we calculated the amplitude of eight major tidal constituents from the results and compared them to the global ocean tide loading model FES2004. The experimental results showed that absolute positioning and positioning done every hour during the observation time of 2 hours, which yielded an outcome similar to the reference ocean tide loading model, were better approaches for extracting tide constituents than relative positioning. As a future study, a long-term GNSS data processing will be required in order to conduct more comprehensive analysis including an extended tidal component analysis.

• Journal of Wetlands Research
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• v.11 no.1
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• pp.105-113
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• 2009

Heat energy exchange is very important processes in the coastal wetland ecosystems. We observed and analyzed the net radiation flux, the sensible heat flux, the latent heat flux and the soil heat flux, which are balanced in the heat energy balance, over a reclaimed land covered with reeds at Goheung, Jeonllanamdo where is horizontally plane. The atmospheric turbulence had been measured in order to estimate the heat transfer during 5 intensive observation periods (IOPs). It was considered that the soil consists of water, fine particles, and vegetation canopy that changes color and density according to the season. We examined the characteristics of the heat flux and the vegetation effect on the air temperature control. It was noted that the heat was transported mainly by latent heat flux in the summer season and the vegetation canopy decreased the daily temperature range due to the heat storage. The air temperature was lower at the IOPs site than near urban area. This showed that the coastal wetland covered with the vegetation control the thermal environment.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.33 no.1
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• pp.31-43
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• 2015

This study had been aimed to conduct the camera calibration on VLBI antenna in the Space Geodetic Observation Center of Sejong City with a low-cost digital camera, which embedded in a mobile phone to determine the three-dimension position coordinates of the VLBI antenna, based on stereo images. The initial values for the camera calibration have been obtained by utilizing the Direct Linear Transformation algorithm and the commercial digital photogrammetry system, PhotoModeler $Scanner^{(R)}$ ver. 6.0, respectively. The accuracy of camera calibration results was compared with that the camera calibration results, acquired by a bundle adjustment with nonlinear collinearity condition equation. Although two methods showed significant differences in the initial value, the final calibration demonstrated the consistent results whichever methods had been performed for obtaining the initial value. Furthermore, those three-dimensional coordinates of feature points of the VLBI antenna were respectively calculated using the camera calibration by the two methods to be compared with the reference coordinates obtained from a total station. In fact, both methods have resulted out a same standard deviation of $X=0.004{\pm}0.010m$, $Y=0.001{\pm}0.015m$, $Z=0.009{\pm}0.017m$, that of showing a high degree of accuracy in centimeters. From the result, we can conclude that a mobile phone camera opens up the way for a variety of image processing studies, such as 3D reconstruction from images captured.

• Korean Journal of Agricultural Science
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• v.19 no.1
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• pp.16-27
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• 1992

To determine a potential of new sludge fertilizer for horticultural crops, comparative studies between commercial fertilizers (Jandibiryo and Wonyebokbi) and sludge fertilizer (Sludgebiryo) were made through examining the growth responses on zoysiagrass (Zoysia japponica Steud.) and several horticultural plants. 1. The pH of new sludge fertilizer remained near 6.5 regardless the particle size. The solubility of elements was highest in phosphorus, followed by nitrogen and potassium in the order. Especially, desorption of potassium was continued up to 48 hrs after solubilization. 2. There was an increase in shoot number per plant, length of stolon and rhizome, and root weight as well as clipping yield of zoysiagrass in the treatment of large size Sludgebiryo compared to small one and Jandibiryo. 3. Regardless the size of fertilizers, Sludgebiryo increased flower numbers in salvia (Salvia officinalis L. 'Hatzazz') compared to Wonyebokbi, although the difference was not great, However, leaf area and fresh weight of plant were more increased in Wonyebokbi application. 4. Flower diameter of marigold (Tagetes erecta L. 'Inca') was slightly increased in Sludgebiryo application, but the average number of lateral shoots and fresh weight per plant were significantly increased in the treatment of Wonyebokbi application. 5. Sludgebiryo effectively increased the length of both main and lateral shoots, number of flowers and weight of shoot in vinca (Vinca rosea L. 'Little Linde'), but root growth of plant was higher in Wonyebokbi application. 6, No differences between Wonyebokbi and Sludgebiryo were found in promoting the growth of leaves of perilla (Perilla frutescens Hara 'Yubsil' ), but chlorophyll content and seed weight were slightly higher in the application of Wonyebokbi compared to Sludgebiryo. In conclusion, the effectiveness of Sludgebiryo for horticultural plants was almost equal to commercial fertilizers such as Jandibiryo or Wonyebokbi. Expecially, Sludgebiryo appeared to effective on the growth of zoysiagrass, and the increase of flower size and numbers in flower crops. Results indicate that new-made Sludgebiryo can be recommended for turfgrass culture, and the flower crops in which quality depends on flower number and flower size.

• Journal of Korean Society for Geospatial Information Science
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• v.16 no.1
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• pp.83-93
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• 2008

The topographic effect is one of the most important component in the solution of the geodetic boundary value problem (geodetic BVP). Therefore, topographic effect should be considered properly for developing the precise geoid model, especially for the area where contains many mountains like Korea. The selection of gravity reduction method in the context of the precise geoid determination depends on the magnitude of its indirect effect, the smoothness and magnitude of the reduced gravity anomalies, and their related geophysical interpretation. In this study, Korean digital elevation model with 100m resolution was constructed and topographic effect was calculated by three reduction methods as like Helmert condensation method and RTM method and Airy-isostatic reduction method. Through the analysis of computation results, we can find that RTM reduction method is the best optimal method and the results shows that gravity anomaly and indirect effect of geoidal height are $0.660{\pm}13.009mGal$, $-0.004{\pm}0.131m$ respectively and it is the most gentle slow of the three methods. Through this study, it was found that the RTM method is better suitable for calculating topographic effect precisely in context of precise geoid determination in Korea than other reduction methods.