• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.20 no.1
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• pp.39-46
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• 2002

This paper shows what is point to be considered at that time in cadastral settlement surveying after declination analysis between GPS and traditional surveying at coordinate result of cadastral triangulation points and supplementary point in site selected deplaning of streets which is surveyed traditional surveying. In the case that coordinates of cadastral triangulation assistance points was decided by standard of the existing cadastral triangulation points that direction of the error vector is in opposition, authors could know all errors was reduced inside coordinate by error being offset each other through the results of study. The coordinates result of cadastral triangulation point by standard of the cadastral triangulation points reduces the deviation value through error that an intersection points was centered being offset each other but through the result that a tendency of errors occurrence is analyzed goniometrys, supplementary points that is close to cadastral triangulation assistance points was affected by error of cadastral triangulation assistance points.

• Journal of the Korean Geosynthetics Society
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• v.16 no.2
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• pp.55-66
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• 2017

The standard piezocone penetration rate of 2 cm/s is proposed in specifications regardless of soil type. However, conditions of standard Piezo Cone Penetration (CPTU) Testings in silty soils with low plasticity vary from undrained to partially drained or fully drained penetration conditions. The partially drained shear strengths of Incheon, Hwaseong and Gunsan silty soils were estimated from the analysis results of the distributions of CPTU-based shear strengths. The CPTU-based shear strengths were compared between the undrained shear strength line and the fully drained shear strength line, which were determined from approximately ${\varphi}^{\prime}=3^{\circ}$ and ${\varphi}^{\prime}=15^{\circ}$, respectively. The internal friction angles obtained from the back analysis and UU-tests tended to increase with decreasing plasticity index, which range approximately from ${\varphi}^{\prime}=2^{\circ}$ to ${\varphi}^{\prime}=14^{\circ}$. The results matchs well with CPTU-based estimation results.

• Applied Microscopy
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• v.36 no.1
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• pp.17-23
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• 2006

The pregnant rats were given a drinking water administration of the sodium fluoride and normal saline for control animals. The sodium fluoride produced cellular changes of odontoblast with consistent response. Compare to control group, the odontoblasts that were administrated by sodium fluoride, showed significantly ultrastructural differences including large number of free ribosomes and swelled mitochondria in dose-dependent manner (300 ppm). From fine structural and morphological investigations of the changes in odontoblast, there were three distinctive structural changes: (1) destruction of the endoplasmic reticulum, (2) swelling of the mitochondria, and (3) severe cellular derangement of the endoplasmic reticulum and mitochondria. From this consecutive structural change, we observed that sodium fluoride temporarily affects the cell organelles in odontoblasts (100, 200 ppm), suggesting it is important that optimal concentration of the sodium fluoride in developing fetus of the rat.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.23 no.6
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• pp.66-71
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• 2009

This paper presents the grounding impedance behaviors of counterpoise exposed to impulse currents. The transient and conventional grounding impedances of three counterpoises having the length of 10, 30 and 50[m] were measured and analyzed as a function of the injection point of impulse currents. As a result, the trend of the conventional grounding impedances measured as a function of injection of impulse current is similar to the transient grounding impedance of counterpoise. The injection point of impulse current has great influence on the transient grounding impedance characteristics of counterpoise. The transient grounding impedance characteristics in a short time range are strongly dependent on the length of counterpoise. The transient characteristics of grounding impedance of 10[m] counterpoise subjected to the impulse current was capacitive behavior, on the other hand, those of 30[m] and 50[m] counterpoises were inductive behavior. It is found that the grounding conductor should be connected to the central point of counterpoise.

• Journal of Navigation and Port Research
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• v.33 no.1
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• pp.21-25
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• 2009

The ship without thrusters and special propulsion system is supported by the tug boats during berthing and unberthing. The orders to tug boats are made by a pilot. If the positions of ship, tug boats and port are displayed in 2D map, it will be helpful to pilots. In this research, a network-based pilot supporting system(NPSS) has been conceptually designed NPSS, necessary for safe and efficient pilot, has two main functions. One is the monitoring of the situation of berthing and unberthing. And the other is the automatic calculation of the tug forces considering environmental conditions. The NPSS is designed on the basis of network system around the harbor. The NPSS will be validated using ship-handling simulator in the future.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2017.10a
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• pp.274-276
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• 2017

Korean e-Navigation is a system that introduced to reduce maritime accidents. In order to reduce marine accidents, Korean e-Navigation provides the following services-"Vulnerable Vessel Monitoring", "Vulnerable Vessel support & monitoring", "Optimal safety route", "ENC Streaming for Small Vessel", "Tug & Barge Support", "Maritime Safety Information Providing". Each Service is a system separated into finctional units and integrated into Korean e-Navigation. Korean e-Navigation is introducing data middleware to integrate each service and the DDS(Data Distribution Service) is judged to be effective. Thus, this paper analyzed the characteristics of DDS middleware types suitable for each service of e-Navigation.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.5
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• pp.3022-3029
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• 2015

This study presents experiments to visualize the internal flow and heat transfer characteristics of thermosyphon with immiscible of water-FC40 adopted as binary working fluid. Three different regimes depending on the amount of heat flux applied to the thermosyphon were observed: natural convection, pulse boiling, and continuous boiling. Boiling incipience took place in water, which has lower vapor pressure than FC40. During natural convection water was vaporized in liquid pool while liquid film flows were formed. On the other hand, meanwhile bubbles were generated in the liquid pool during pulse and continuous boiling, the binary working fluid of water-FC40 was observed as the mixture throughout a whole range of the thermosyphon.

• Journal of Korean Society of Water and Wastewater
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• v.30 no.6
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• pp.755-764
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• 2016

Pressure retarded osmosis (PRO) processes can be implemented on a number of water types, using different technologies and achieving various power outcomes. In this study, Sewage facility effluent was used for feed solution of PRO and synthetic NaCl water for draw solution. This study was conducted to investigate effect of water quality of pretreatment on power density and flux decline in PRO process. The results show that organic and particulate foulants have to be removed for more stable operation. Flourescence technique with EEM enables to investigate the chemical properties of aquatic organic matter by extracting spectral information. Humic/fulvic matters and soluble microbial by-products were analyzed as the most affecting factors on the PRO performance. As a result of analyzing the whole system based on the energy consumption of the unit process, specific energy consumption(SEC) of the applicable technology for PRO pre-treatment should be about $0.2kWh/m^3$ or less.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.238-238
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• 2010

최근 전자산업의 발전은 형상 면에서 경박 단소화로 급속하게 진행되고 있으며, 전자소자 내부에서의 배선재료로 사용되고 있는 알루미늄(Al) 박막의 두께 역시 얇아지고 있다. 두께가 20 nm 이하로 작은 극박막 범위에서 박막의 두께 증가에 따라 전기가 잘 흐르기 시작하는 박막의 최소두께로 정의 되는 유착두께를 실시간으로 측정하는 방법을 구현하고 임의의 금속박막과 기판의 조합에 있어서 각각의 재료에 대한 유착두께를 제공함으로써 향후 미세전자소자의 제작시 배선 재료의 선택에 대한 기초자료를 축적할 수 있다. 또한 금속박막의 증착공정 직전에 기판을 표면처리 하여 기판을 활성화시킬 때 표면처리가 박막의 유착두께에 미치는 영향에 대해 박막의 미세구조 변화 관점에서 연구함으로써 여러 가지 금속박막에 대한 유착두께를 줄일 수 있는 방법을 도출 할 수 있다. 본 연구에서는 유리 기판 위에 사진 식각 공정으로 패턴을 형성하고 패턴이 형성된 유리 기판은 스퍼터에 연결된 4 point probe에 구리 도선으로 연결한 후 DC 마그네트론 스퍼터법으로 Al을 증착하면서 실시간으로 시간에 따른 전기저항을 측정을 하였다. 이때 스퍼터 내부 진공도는 $4.6\;{\times}\;10^{-5}\;torr$ 까지 낮춰준 후 Al을 증착 할 때 진공도는 $1.1\;{\times}\;10^{-2}\;torr$로 맞춰주고 Ar 가스를 20 sccm 넣어준다. 1초 간격으로 전기저항을 측정한 결과 25초대에 전기저항이 급격히 감소하였으며 이때 Al 박막의 두께는 $120{\AA}$ 이고 이 두께에서부터 전류의 흐름이 좋은 것을 알 수 있다. 박막 두께에 따른 특성을 알기위해 UV 영역의 빛을 사용하는 광전자 분광기(Photoelectron Spectrometer)를 이용해 일함수를 측정하였다. Al 의 일반적인 일함수는 4.28 eV 이며, 두께가 $120{\AA}$일 때의 일함수는 4.2 eV로 거의 비슷한 값을 얻었다. 전류가 잘 흐르기 전인 12초대에서 두께가 $60{\AA}$일 때 일함수는 4.00 eV 이고 전류가 흐르기 시작한 후 50초대에서 Al 박막 두께가 $200{\AA}$ 일 때 일함수는 4.28 eV 로 일반적인 Al의 일함수와 같은 값을 얻을 수 있었다. 광전자 분광기술은 전자소자에서 중요한 전자의 성능예측에 도움을 줄 수 있으며 물질의 표면에서 더욱 다양한 정보를 얻을 수 있다. 또한 실시간 전기저항 측정을 통한 금속박막의 전기전도 특성과 미세구조에 대한 기초 자료를 제공함으로써 신기술 발전에 공헌할 것이다.

• 한국해양학회지
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• v.22 no.2
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• pp.71-79
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• 1987

We studied the annual variation of water temperatures in the upper 200m off southeast coast of Korea by means of harmonic analysis of the temperatures at 10 standard depths of 51 stations. The distributions of the mean temperature in coastal zone are almost parallel to the coast, whereas those in offshore are almost zonal. With an increase of depth, the annual amplitude decreases nearly exponentially and the annual phase increases nearly linearly. The average e-folding depth for the annual amplitudes is 65m, vertical change of the annual phase is 180 per 200m, and the vertical eddy conductivity is $4\textrm{cm}^2/sec$. Annual variations of temperatures in the coastal zone of a few tens miles from the coast are considerably different from those in offshore area. The e-folding depths in coastal zone are shallower than those in offshore region, and the changes of phase with depths in coastal zone are smaller than those in offshore region.