• Journal of the Korean Association of Geographic Information Studies
• /
• v.9 no.1
• /
• pp.168-178
• /
• 2006

In recent years, an ingress of mass jellyfish into cooling water intake system causes interruption of electric power production at the Uljin nuclear power plant. Therefore, monitering and forecast on the mass ingress of marine organisms are demanded as one of the early preventing measurements. Sea water movement is a major factor on the ingress of marine organisms like Moon jellyfish which has weak self-mobile ability. When sea surface flow direction adjacent to the Uljin is the northwest, the jellyfish on the Tsushima warm currents move to the Uljin power plant. To detect the direction of sea surface warm flows, the spatial range with $25km{\times}25km$ is set up and NOAA sea surface temperature(SST) data are collected in this area. For the statistical analysis, the SST data are made as GIS point data and geostatistical analysis of ArcGIS is used. Analyzing directional semivariogram, the anisotropy of the SST point data are calculated and warm flow direction is detected. This experimental results are expected to use as an element technology for the early warning system development of mass jellyfish ingress in power plant.

• 한국지형공간정보학회:학술대회논문집
• /
• 2002.03a
• /
• pp.106-112
• /
• 2002

최근 급속한 도시의 팽창 및 신도시 건설과 산업의 발전으로 가스시설은 꾸준히 확대되고 있는 실정이다. 그리고 94년 아현동 도시가스사고와 95년 대구 도시가스사고 이후로 도시 가스 시설물의 대한 안전 대책 및 시설물 관리에 대한 국민들의 관심이 증대되었다. 이러한 흐름에 따라 가스회사들은 GIS 기술을 도입하여 기존에 수작업으로 관리되고 있는 가스시설 정보체계를 전산화하여 항상 최신의 현황을 유지하고, 사고 발생시 신속한 대처 방안 및 피해예측을 위한 시스템을 개발하기 위하여 많은 연구를 진행하고 있는 실정이다. 본 연구의 목적은 안전이 중요시되는 가스시설물에 대하여 가스사고 발생시 신속한 대처 및 처리방안을 제시할 수 있는 GIS 기반의 가스사고 관리시스템을 개발하는데 있다. GIS의 가스사고 관리시스템에서는 사고 발생시에 시설물 관리자가 사고 지점을 선택하여 우선적으로 공급을 중단해야 할 관로를 제시하고 사고지점을 검색하여 차단해야 할 밸브에 대한 정보를 신속히 제공하여 대응 방안을 제시 할 수 있도록 하였다. 아울러 가스공급이 중단되는 지역에 대한 정보를 추출하여 피해범위를 산정하여 효율적인 사고 관리를 지원하도록 구성되었으며, 이와 함께 잔존가스량을 구하여 사고후의 대처방안을 마련할 수 있는 기능을 제공하도록 하였다. 향후 연구과제로는 원격으로 가스 시설물을 감시하고 제어할 수 있는 원격감시/제어시스템(SCADA System)과 연계를 통하여 가스사고 후에 신속한 피해예측 및 피해를 최소화 할 수 있는 방안제시 및 GPS를 활용하여 신속한 사고처리를 할 수 있는 활용 방안을 연구하여 체계적이고 종합적인 가스사고의 관리가 필요하다고 사료된다. 또한, 사고 후의 긴급 대처방안 뿐만 아니라 잔존가스량을 이용하여 수용가에 가스의 신속한 재공급을 위한 정보의 제공까지 한 단계 발전된 시스템의 개발이 추진되어야 한다.남산지역에 대해 정사영상과 10m간격의 DEM을 제작하였으며 1:1000 수치지도를 통해 제작된 DEM과 비교한 결과 총 43990개 격자점의 표고 차이는 평균 5.98m였다.여재 높이 100 cm에서 원수를 하향류 및 상향류로 주입하면서 하향류 20, 40, 80, 100 cm, 상향류 20, 40, 60, 80, 100 cm에서 시료를 채취하여 분석한 결과 모두 원수가 주입되는 부근 여재 높이 20 cm에서 가장 많이 제거되었다. 상향류 보다 하향류로 원수를 주입했을 때 제거효율이 높았다. $Fe^{+++}$을 $Fe^{++}$로 환원하는 $O^{-}_{2}{\cdot}$의 작용을 대신할 수 있음을 증명하며 이와같은 ascorbate 의존적인 $OH{\cdot}$ 의 생성은 ascorbate가 조직손상에 관여할 가능성을 시사하였다.었다. 정확한 예측치를 얻기 위하여 불균질 조직이 조사야에 포함되는 경우 보정이 요구되며, 골반의 경우 골 조직의 보정이 중요한 요인임을 알 수 있었다. 이를 위하여 불균질 조직에 대한 정확한 정보가 요구되며, 이는 CT 영상을 이용하는 것이 크게 도움이 되리라 생각된다.전시 슬러지층과 상등액의 온도차를 측정하여 대사열량의 발생량을 측정하고 슬러지의 활성을 측정할 수 있는 방법을 개발하였다.enin과 Rhaponticin의 작용(作用)에 의(依)한 것이며, 이는 한의학(韓醫學) 방제(方劑) 원리(原理)인 군신좌사(君臣佐使) 이론(理論)에서 군약(君藥)이 주증(主症)에 주(主)로 작용(作用)하는 약물(藥物)이라는 것을 밝혀주는 것이라고 사료(思料)된다.일전 $13.447\;{\mu}g/hr/g$, 섭취 7일중 $8.123\;{\mu}g/hr/g$, 절식 14일후 $10.612

• Journal of the Korean earth science society
• /
• v.44 no.6
• /
• pp.629-642
• /
• 2023

Currently, low and intermediate level radioactive waste is being disposed of at the Gyeongju disposal site for permanent isolation. Since 2006, the Korea Radioactive Waste Agency has been conducting site characteristics surveys continuously verifying changes in the site based on the site monitoring and investigation plan. The hydrogeochemical environment of the disposal site is considered for the evaluation of natural barriers. However, the seawater must be considered because of the regional characteristics of Gyeongju, which is near the East Sea. Therefore, this study, collected 30 samples for deriving the groundwater quality data from seven wells and compared with two seawater samples collected from October 2017 to June 2022. Additionally, the study explores the groundwater monitoring method using statistical tools such as clustering and background concentration analysis. The groundwater samples in the study area were classified into two to four clusters depending on their chemical constituents-especially, EC, HCO₃, Na, and Cl-using statistical analysis, molar ratio, and K-means clustering.

• Journal of the Earthquake Engineering Society of Korea
• /
• v.10 no.6 s.52
• /
• pp.9-18
• /
• 2006

This paper presents schematically the monitoring system installed in Yongjong Bridge, a self-anchored suspension bridge located in the expressway linking Seoul and Incheon International Airport. Automatic measurement of instrumented civil engineering structures is now widely applied for behavior monitoring during construction in field as well as long-term monitoring for lifetime assessment of bridge structures. A representative example of results that can be acquired through structural health monitoring system is presented by means of data measured during a few years after the opening of the bridge. In order to effectively measure the tension force for hangers that have relatively short length or high tension force, a static tension measurement device has been explored. Newly equipped railway system on the existing bridge results in change of dead load, consequently dynamic characteristics have also been changed. This result can be detected by the monitoring system during and after railway construction.

• Journal of the Institute of Electronics and Information Engineers
• /
• v.53 no.8
• /
• pp.107-112
• /
• 2016

Safety Critical Instrumentation and Control Systems perform those functions to maintain nuclear power plants' parameters within acceptable limits established for a design basis events and anticipated operating occurrence to ensure safety function. Those digitalized systems shall protect inadvertent and non-malicious behavior to ensure the reliable operation of systems, known as a Secure Development and Operational Environment(SDOE). SDOE would be established through managerial and technical controls. The objective of this paper is to evaluate the effectiveness of Cyclic Redundancy Checksum diagnostic, which is one of technical controls for SDOE, that can confirm the integrity of software of I&C systems to establish the secure environment. The results of this assessment would be the practical implementation of design and safety review of nuclear I&C systems.

• Journal of the Korean earth science society
• /
• v.25 no.6
• /
• pp.495-501
• /
• 2004

Using numerous ground-based or space-based telescopes by many astronomers, AGN spectroscopic monitoring campaigns have been carried out over many years to study the variability of continua and emission lines. We investigate the SWP IUE spectra of a large aperture configuration for the Seyfert 1 galaxies NGC 4151 and NGC 5548. We estimate the BLR electron number densities and their variation from the line ratios of C III] 1909 to Si III] 1892. With the ratios of C IV 1550 to C III] 1909 which give us the information on the ionization parameter of BLR, we try to find the physical conditions of the BLR and activities of he super massive black hole surroundings. The BLR density variations scale as 4 and 8 for NGC 4151 and NGC 5548, respectively. Based on the BLR size and C III] line profiles, we found both black hole masses as about $10^7$ $M_{\odot}$.

• Polymer(Korea)
• /
• v.27 no.3
• /
• pp.249-254
• /
• 2003

The variation of chemical structure and physical properties of crosslinked polyethylene (XLPE) during thermal aging process was investigated. The formation of carbonyl functional group resulting from thermal oxidation reaction of XLPE was monitored using X-ray photoelectron spectroscopy and near infrared (NIR) spectroscopy. It was observed that the intensity of carbonyl peak observed at 1715 nm linearly increased with aging time in NIR spectroscopy. The linear relationship between NIR peak absorbance and aging time confirmed that NIR spectroscopy might be used as a proper tool for monitoring the aging process of polymeric materials. Also the formation of crosslinks during the aging process was monitored using thermal mechanical analysis, stress-strain test, and Shore hardness test. The change in the physical properties, such as the increase in the glass transition temperature from 110 to 132$^{\circ}C$, the decrease in the strain from 265 to 110%, as well as the increase in the shore D hardness from 32 to 50, was observed during the aging process.

• Korean Journal of Remote Sensing
• /
• v.30 no.1
• /
• pp.13-24
• /
• 2014

Satellite remote sensing data have been valuable tool for volcanic ash monitoring. In this study, we present the results of application of satellite remote sensing data for monitoring of volcanic ash for three major volcanic eruption cases (2008 Chait$\acute{e}$n, 2010 Eyjafjallaj$\ddot{o}$kull, and 2011 Shinmoedake volcanoes). Volcanic ash detection products based on the Moderate Resolution Imaging Spectro-radiometer (MODIS) observation data using infrared brightness temperature difference technique were compared to the forward air mass trajectory analysis by the HYbrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model. There was good correlation between MODIS volcanic ash image and trajectory lines after the volcanic eruptions, which support the feasibility of using the integration of satellite observed and model derived data for volcanic ash forecasting.

• Journal of the Korean Society for Nondestructive Testing
• /
• v.29 no.4
• /
• pp.299-307
• /
• 2009

Emerging fiber optic sensor technologies have shown great potential to overcome the difficulties associated with conventional sensors. Fiber optic sensors are immune to EM noise and electric shock and thus can be used in explosion-prone areas. Several kinds of fiber optic sensors have been developed over the last two decades to take advantage of these merits. There have also been many field applications of fiber optic sensors for structural health monitoring as NDT/HDE. However, very few sensors, particularly a load cell have been successfully commercialized. This Paper Presents a load cell using fiber Bra99 gra1ing (FBG) sensors. The shape of the load cell is a link type, and three FBG sensors are used for measuring strains at three different points. Especially, these strains are processed with a differential method in order to exclude common mode noise such as temperature. Moreover, the sensitivity, the linearity and the resolution of the load cell were successfully verified from the experiment of tension test.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.21 no.1
• /
• pp.75-81
• /
• 2007

This paper dealt with the design and implementation of an expert system to monitor and diagnose the lightning arresters in GIS substations. The expert system consists of a data acquisition module(DAM) based on microprocessor and diagnostic algorithms. The DAM measures and analyzes several parameters necessary for the arrester diagnosis such as system voltages, leakage current components, and temperatures. Also, it includes an intelligent surge counter which can record the date and tin, the polarity, and the amplitude of surge currents. All the data acquired is transmitted to a remote computer by a low rate wireless network specified in IEEE 802.15.4 to avoid electromagnetic intereference under high voltage and large current environments. The decision-making for the arrester diagnosis completes with a Java Expert System Shell(JESS) which is composed of a knowledge base, an inference engine and a graphic user interface(GUI).