• Title/Summary/Keyword: change of observation

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Analysis of Impact of Climate Change on River Flows in an Agricultural Watershed Using a Semi-distributed Watershed Model STREAM (준분포형 유역모델 STREAM을 이용한 기후변화가 농업유역의 하천유량에 미치는 영향 분석)

  • Jeong, Euisang;Cho, Hong-Lae
    • Journal of Korean Society on Water Environment
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    • v.35 no.2
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    • pp.131-144
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    • 2019
  • Climate Change affects the hydrological cycle in agricultural watersheds through rising air temperature and changing rainfall patterns. Agricultural watersheds in Korea are characterized by extensive paddy fields and intensive water use, a resource that is under stress from the changing climate. This study analyzed the effects of climate change on river flows for Geum Cheon and Eun-San Choen watershed using STREAM, a semi-distributed watershed model. In order to evaluate the performance and improve the reliability of the model, calibration and validation of the model was done for one flow observation point and three reservoir water storage ratio points. Climate change scenarios were based on RCP data provided by the Korea Meteorological Administration (KMA) and bias corrections were done using the Quantile Mapping method to minimize the uncertainties in the results produced by the climate model to the local scale. Because of water mass-balance, evapotranspiration tended to increase steadily with an increase in air temperature, while the increase in RCP 8.5 scenario resulted in higher RCP 4.5 scenario. The increase in evapotranspiration led to a decrease in the river flow, particularly the decrease in the surface runoff. In the paddy agricultural watershed, irrigation water demand is expected to increase despite an increase in rainfall owing to the high evapotranspiration rates occasioned by climate change.

Nano-Scale Observation of Nanomaterials by In-Situ TEM and Ultrathin SiN Membrane Platform

  • An, Chi-Won
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.02a
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    • pp.657-657
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    • 2013
  • In-situ observations of nano-scale behavior of nanomaterials are very important to understand onthe nano-scale phenomena associated with phase change, atomic movement, electrical or optical properties, and even reactions which take place in gas or liquid phases. We have developed on the in-situ experimental technologies of nano-materials (nano-cluster, nanowire, carbon nanotube, and graphene, et al.) and their interactions (percolation of metal nanoclusters, inter-diffusion, metal contacts and phase changes in nanowire devices, formation of solid nano-pores, melting behavior of isolated nano-metal in a nano-cup, et al.) by nano-discovery membrane platform [1-4]. Between two microelectrodes on a silicon nitride membrane platform, electrical percolations of metal nano-clusters are observed with nano-structures of deposited clusters. Their in-situ monitoring can make percolation devices of different conductance, nanoclusters based memory devices, and surface plasmonic enhancement devices, et al. As basic evidence on the phase change memory, phase change behaviors of nanowire devices are observed at a nano-scale.

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Coastline Change Analysis using Geospatial Information (지형공간정보를 이용한 해안선 변화량 분석)

  • Kim, Yong-Suk;Lee, Jae-One;Hong, Soon-Hyun;Lee, Kang-Won
    • Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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    • 2007.04a
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    • pp.225-230
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    • 2007
  • Currently, looking at the field of producing national coastlines, the lengths of coastlines are inaccurate due to the vague definition of dividing coastline boundaries and insufficient observation data. The level of accuracy and reliability of previous data are also in the very low. This paper used aerial photographs with certain intervals to monitor the change in coastal areas of Songjeong, Haeundae, Kwanganri, Songdo and Dadaepo. The local area subjected for this research was limited to areas near Busan. Launching quantitative/time series analyses on the change of coastal areas using aortal photographs, satellite image data and RTK-GPS surveys. And developing an automatic edge detection program to extract coastlines, suggesting the performance of the program and analyzing the efficiency of the program.

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A Study on the Color Change in a Union Fabric simulated using a 3-dimensional CAD Software and Image Analysis

  • Kim, Jong-Jun
    • Journal of Fashion Business
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    • v.10 no.6
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    • pp.9-15
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    • 2006
  • Colors of textile products or fashionable clothing play one of the most important roles. From the point of visual cues, the realism of an image is the result of a good interaction of local light scattering or transmittance model applied. A 3-dimensional CAD software was used to construct a solid plain fabric model. In order to simulate a union fabric with different warp and filling colors, rendering was performed on the fabric model. It was demonstrated that the iridescent effect, pearl effect, or superficial color change effect of the union fabric during wearer's movement could be explained using the fabric models at inclined fabric positions during viewer's observation.

Clinical Observation on 3 Cases of Dry Eye Syndrome (안구 건조증 환자의 치험 3례)

  • Choi, Eun-Hee;Jeon, Ju-Hyun;Kim, Young-Il
    • Journal of Acupuncture Research
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    • v.24 no.4
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    • pp.237-245
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    • 2007
  • Objective : The Dry Eye Syndrome is characterized by reduction of the stability of the tearfilm and a set of alterations of the eye surface which could relate to tear quality, normal makeup of tearfilm and alterations in blinking or regular closing of eyelids. We treated 3 patients who was suffering with severe Dry Eye Syndrome and assessed the effectiveness of Oriental Medicine in the treatment of Dry Eye Syndrome. Methods : The patients were treated by acupunture, Gi Guk Yang Hyeol-decoction(Qijuyangxie-decoction). The improvement of the symptom was judged the subjective symptoms by the change of Ocular Surface Disease Index. Result : We observed in 2 cases of the patient significant decrease in the frequency of subjective symptoms, 1 case was not treated. Conclusion: The Oriental Medicine had effective results in Dry Eye syndrome. We need to have more observation and examination of Dry Eye syndrome.

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Analysis of Air Temperature Change Distribution that Using GIS technique (GIS 기법을 이용한 대기온도 변화 분포 분석)

  • Jung, Gyu-Young;Kang, In-Joon;Kim, Soo-Gyum;Joo, Hong-Sik
    • Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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    • 2010.04a
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    • pp.395-397
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    • 2010
  • AWS that exist in Pusan is watching local meteorological phenomena established in place that the weather observatory does not exist by real time, and is used usefully to early input data of numerical weather forecasting model. I wished to display downtown of Pusan and air temperature change of peripheral area using this AWS data. Analyzed volatility using AWS observation data for 5 years to recognize air temperature change of Pusan area through data about temperature among them. Drew air temperature distribution chart by season of recapitulative Pusan area applying IDW linear interpolation with this.

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Short-term Variation in Class A Pan Evaporation (대형증발계 증발량의 일 변화)

  • 이부용
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.4 no.4
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    • pp.197-202
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    • 2002
  • A new method is used to estimate the amount of water evaporation from Class A Pan with higher precision and accuracy. The principle of method is to detect the weight change of a buoyant sinker resulting from a change in water level of Class A Pan. A strain-gauge load cell is used to measure the weight change. Field observation of evaporation was done at Pohang Meteorological Station from June 24 to August 4, 2002. By using this new method, it is possible to measure hourly evaporation accurately even under a strong solar radiation and wind disturbance, enabling a direct comparison of evaporation with other meteorological elements. At night, under low humidity and high wind speed conditions, more evaporation was recorded than during daytime. Maximum evaporation rates observed during this period exceed 1.0 mm/hour under the sunny and windy conditions with low humidity. To understand relationships between meteorological elements and latent heat flux at ground level, we suggest intensive held experiments using high accuracy evaporation recording instruments with hourly time interval.

Implementation of ESGF Data Node for International Distribution of CORDEX-East Asia Regional Climate Data

  • Han, Jeongmin;Choi, Jaewon
    • International Journal of Contents
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    • v.17 no.1
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    • pp.61-70
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    • 2021
  • As the resolution of climate change scenario data applied with regional models increased, Earth System Grid Federation (ESGF) was established around major climate-related organizations to jointly operated and manage large-scale climate data. ESGF developed standard software to provide model output, observation data management, dissemination, and analysis using Peer to Peer (P2P) computing technology. Roles of each institution were divided into index and data nodes. Therefore, ESGF data node was established at APEC Climate Center in Korea on behalf of Asia to share data on climate change scenarios of CORDEX-East Asia (CORDEX-EA) to study climate changes in Eastern Asia. Climate researchers are expected to play a large role in researching causes of global warming and responding to climate change by providing CORDEX-EA regional model data to the world through ESGF data node.

The Effect of HPMC Concentration on the Morphology and Post Drawing of Wet Spun Regenerated SF/HPMC Blend Filaments

  • Ko, Jae-Sang;Um, In-Chul
    • International Journal of Industrial Entomology and Biomaterials
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    • v.19 no.1
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    • pp.181-185
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    • 2009
  • In this paper, the regenerated silk fibroin (SF)/hydroxypropyl methylcellulose (HPMC) blend filaments were prepared by wet spinning and the effect of HPMC concentration on the post drawing and morphology of blend filaments was elucidated. The result of maximum draw ratio indicated that the wet spinnability of wet spun SF / HPMC was improved with increasing HPMC concentration until 8% and remained constant after that concentration. The SEM observation revealed that the enhanced wet spinnability of blend filaments was strongly related to the morphological change by increasing HPMC concentration. Regardless of HPMC concentration, as SF content was reduced, the wet spinnability of blend film decreased resulting in reduced maximum draw ratio. It was also found by SEM observation that the cross section of blend filament deviated from circularity with an increase of HPMC content.

Ellipso-Microscopic Observation of Titanium Surface under UV-Light Irradiation

  • Fushimi, K.;Kurauchi, K.;Nakanishi, T.;Hasegawa, Y.;Ueda, M.;Ohtsuka, T.
    • Corrosion Science and Technology
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    • v.15 no.6
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    • pp.265-270
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    • 2016
  • The ellipso-microscopic observation of a titanium surface undergoing anodization in $0.05mol\;dm^{-3}$ of $H_2SO_4$ was conducted. During irradiation by ultra-violet (UV) light with a wavelength of 325 nm, the titanium surface allowed for the flow of a photo-induced current and showed up as a bright, patch-like image on an ellipso-microscopic view. The brightness and patch-pattern in the image changed with flowing photo-induced current. The changes in the brightness and the image corresponded to the formation and/or degradation of titanium oxide due to the photo-electrochemical reaction of the oxide. An in situ monitoring using the ellipso-microscope revealed that the film change was dependent on the irradiation light power, by UV-light increases the anodic current and results in the initiation of pitting at lower potentials as compared with the non-irradiated condition.