• Title/Summary/Keyword: change of observation

Search Result 1,674, Processing Time 0.034 seconds

Assessment of Historical and Future Climatic Trends in Seti-Gandaki Basin of Nepal. A study based on CMIP6 Projections

  • Bastola Shiksha;Cho Jaepil;Jung Younghun
    • Proceedings of the Korea Water Resources Association Conference
    • /
    • 2023.05a
    • /
    • pp.162-162
    • /
    • 2023
  • Climate change is a complex phenomenon having its impact on diverse sectors. Temperature and precipitation are two of the most fundamental variables used to characterize climate, and changes in these variables can have significant impacts on ecosystems, agriculture, and human societies. This study evaluated the historical (1981-2010) and future (2011-2100) climatic trends in the Seti-Gandaki basin of Nepal based on 5 km resolution Multi Model Ensemble (MME) of 18 Global Climate Models (GCMs) from the Coupled Model Intercomparison Project Phase 6 (CMIP6) for SSP1-2.6, SSP2-4.5 and SSP5-85 scenarios. For this study, ERA5 reanalysis dataset is used for historical reference dataset instead of observation dataset due to a lack of good observation data in the study area. Results show that the basin has experienced continuous warming and an increased precipitation pattern in the historical period, and this rising trend is projected to be more prominent in the future. The Seti basin hosts 13 operational hydropower projects of different sizes, with 10 more planned by the government. Consequently, the findings of this study could be leveraged to design adaptation measures for existing hydropower schemes and provide a framework for policymakers to formulate climate change policies in the region. Furthermore, the methodology employed in this research could be replicated in other parts of the country to generate precise climate projections and offer guidance to policymakers in devising sustainable development plans for sectors like irrigation and hydropower.

  • PDF

Effects of Rock Weathering on the Degradation of Engineering Properties (암반풍화도에 따른 지질공학적 특성 저감효과)

  • Lee Chang-Sup;Cho Taechin
    • Tunnel and Underground Space
    • /
    • v.15 no.6 s.59
    • /
    • pp.411-424
    • /
    • 2005
  • Weathering is defined as a process by which surface rock, once formed in the deep ground, is broken down and altered to keep the equilibrium with the ambient environment. In this study granitic rock samples of different weathering grades were collected in the field and the microscopic observation, X-ray diffraction analysis, electron microscopic observation, chemical analysis, and rock property tests were carried out. Formation of secondary minerals, especially clay minerals, by weathering was identified and the mechanism for the change of engineering properties such as rock strength degradation was analyzed. Tunnel model test, Failure behaviour, Shallow tunnel, Unsupproted tunnel length.

A Study on the Effects of Experiential Learning for Environment Based on Living Area (지역기반 환경체험학습의 효과에 관한 연구)

  • Lee, Dong-Yab;Kim, Hee-Cheol;Park, Man-Guen;An, A-Yeong;Lee, Ji-Suk;Lee, Ji-Hee;Cheong, Cheol
    • Hwankyungkyoyuk
    • /
    • v.20 no.1
    • /
    • pp.19-27
    • /
    • 2007
  • This study was intended to answer the question, 'What kinds of effects will be aroused by experiential learning for environment based on living area?'. Experiential learning for environment was operated to 17 elementary school students in 4th grade in Kyeong-san city. The results were drawn analyzing the mind map for the changes of environmental consciousness before and after learning, and they are as below. First, it had an effect to change the meaning association of the relationship between 'river and me'. Meaning association was 'river-a thing' before experiential learning, but it was developed as 'river-a thing-me' after learning. This means that students expanded understanding of the world that they were belonging and self-spatialization was promoted. The expansion of meaning association would be a start point and a method to promote their segmentation for each student. Second, students could self-directly modify misconception and preconception after experiential learning. It showed that students could find meanings in the world that they were belonging by experiential learning for environment, and misconception obtained by concept learning without actual situation could be revised through the truth recognition in meanings, and student could see what things displayed. Therefore preconception would be corrected. Of course, everything would not be completed by just one time of experiential learning, and consistent experience learning should be operated. Third, experiential learning promoted the change of sensitivity. Students had shallow sensitivity, which appeared in the relation with things, since having learned only inside of class without a direct observation. However their sensitivity could be increased by experiencing specific things. Fourth, there was the change of classification recognition. Students found properties of things with a direct observation. It raised their ability to classify things, and to understand an individual thing in 'a class'.

  • PDF

MICROSCOPIC OBSERVATION OF DRAPED COMPOSTTE MATERIALS : Picture Frame Test (직물 복합재료의 드레이핑 미소 거동 관찰: 사진틀 전단실험)

  • Kang Jae-Hoon;Chang Seung-Hwan
    • Composites Research
    • /
    • v.18 no.2
    • /
    • pp.13-19
    • /
    • 2005
  • In this paper deformation of micro-mechanical parameters such as tow interval, tow thickness and change in tow amplitude are investigated by using dry fabrics (Five-harness satin weave) under shear deformation. To evaluate the observation results according to the generated in-plane forces in the material, bias extension, biaxial test results are compared with. It was found that a picture frame test with a misaligned fibre orientation angle shows large differences in deformation between tensile and compressive tow directions.

A Study on the Change of Body Temperature according to Menstrual Cycle (월경주기에 따른 체온변화 관찰)

  • Park, Dae-Soon;Cho, Jung-Hoon;Jang, Jun-Bock;Lee, Kyung-Sub
    • Journal of Oriental Medical Thermology
    • /
    • v.2 no.1
    • /
    • pp.6-10
    • /
    • 2003
  • Purpose : Man is a homoiothermal animal. But by various causes, body temperature can be changed to $1^{\circ}C$. Basal temperature is a very useful method in many fields of OB&GY area. So we observed the change of body temperature according to menstrual cycle. Materials and Methods : We observed 3 female who have very regular 30 days menstrual cycle. The Observation started before the onset of menstruation and body temperature was checked in the same time (11:00 am) of a day. To evaluate the change of body temperature, we examined three points of body. And to observe the body temperature we used the D.I.T.I(Dorex, Inc., USA). Results : On this study we couldn't find the typical biphasic change of body temperature but most of the materials showed the elevation of body temperature on the 14th day. Between the examined three points, the lowest point was showed more typical biphasic change of body temperature.

  • PDF

Assessment of the Impact of Climate Change on Marine Ecosystem in the South Sea of Korea II (기후변화가 남해(북부 동중국해 포함) 해양생태계에 미치는 영향 평가 시범 연구 II)

  • Ju, Se-Jong;Kim, Se-Joo
    • Ocean and Polar Research
    • /
    • v.35 no.2
    • /
    • pp.123-125
    • /
    • 2013
  • According to the Intergovernmental Panel on Climate Change (IPCC), ocean warming and acidification are accelerating as a result of the continuous increase in atmospheric $CO_2$. This may affect the function and structure of marine ecosystems. Recently, changes in marine environments/ecosystems have been observed (increase in SST, decrease in the pH of seawater, northward expansion of subtropical species, etc.) in Korean waters. However, we still don't understand well how climate change affects these changes and what can be expected in the future. In order to answer these questions with regard to Korean waters, the project named 'Assessment of the impact of climate change on marine ecosystems in the South Sea of Korea' has been supported for 5 years by the Ministry of Oceans and Fisheries and is scheduled to end in 2013. This project should provide valuable information on the current status of marine environments/ecosystems in the South Sea of Korea and help establish the methodology and observation/prediction systems to better understand and predict the impact of climate/marine environment changes on the structure and function of marine ecosystems. This special issue contains 5 research and a review articles that highlight the studies carried out during 2012-2013 through this project.

Monitering System of Silicon Wafer Grinding Process Using for the Change of Motor Current (모터 전류 변화를 이용한 실리콘 웨이퍼 연삭 공정 모니터링 시스템)

  • Park S.J.;Kim S.Y.;Lee S.J.;Park B.Y.;Jeong H.D.
    • Proceedings of the Korean Society of Precision Engineering Conference
    • /
    • 2005.06a
    • /
    • pp.104-107
    • /
    • 2005
  • Recently, according to the development of semiconductor industry, needed to high-integration and high-functionality. These changes are required for silicon wafer of large scale diameter and precision of TTV (Total Thickness variation). So, in this research, suggest that the method of monitoring system is using motor current. This method is needed for observation of silicon wafer grinding process. Motor current sensor is consisted of hall sensor. Hall sensor is known to catching of change of current. Received original signal is converted to the diginal, then, it is calculated RMS values, and then, it is analysed in computer. Generally, the change of force is relative to the change of current, So this reason, in this research tried to monitoring of motor current change, and then, it will be applied to analysis for silicon wafer grinding process. using motor current sensor.

  • PDF

Temporal and Spatial Variation of Soil Moisture in Upland Soil using AMSR2 SMC

  • Na, Sang-Il;Lee, Kyoung-Do;Kim, Sook-Kyoung;Hong, Suk-Young
    • Korean Journal of Soil Science and Fertilizer
    • /
    • v.48 no.6
    • /
    • pp.658-665
    • /
    • 2015
  • Temporal and spatial variation of soil moisture is important for understanding patterns of climate change, for developing and evaluating land surface models, for designing surface soil moisture observation networks, and for determining the appropriate resolution for satellite-based remote sensing instruments for soil moisture. In this study, we measured several soil moistures in upland soil using Advanced Microwave Scanning Radiometer 2 (AMSR2) Soil Moisture Content (SMC) during eight-month period in Chungbuk province. The upland soil moisture properties were expressed by simple statistical methods (average, standard deviation and coefficient of variation) from the monthly context. Supplementary studies were also performed about the effect of top soil texture on the soil moisture responses. If the results from this study were utilized well in specific cities and counties in Korea, it would be helpful to establish the countermeasures and action plans for preventing disasters because it was possible to compare with the relationship between soil moisture and top soil texture of each region. And it would be the fundamental data for estimating the effect of future agricultural plan.

Tracking Analysis of Unknown Space Objects in Optical Space Observation Systems (광학 우주 관측 시스템의 미지 우주물체 위치 추적 분석)

  • Hyun, Chul;Lee, Sangwook;Lee, Hojin;Park, Seung-Wook
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.25 no.12
    • /
    • pp.1826-1834
    • /
    • 2021
  • In this paper, we check the possibility of continuous tracking when photographing unknown space objects in a short period of time in an optical observation system on the ground. Simulated observation data were generated for target limited to low-orbit areas. The performance index of the prediction error was set in consideration of the property of targets. Kalman Filter was applied to predict the next location of the target. A constant velocity/acceleration dynamic model was applied to the two axes of the azimuth/elevation of the unknown space object respectively. As a result of performing the Monte Carlo simulation, the maximum error ratio of the maximum nonlinear section was less than 2%, which could be determined to ensure continuous tracking. The CA model had little change in the prediction error value for each case, making it more suitable for tracking unknown space objects. This analysis could provide a foundation for determining the orbit of unknown space objects using optical observation.

High Resolution Fine Dust Mass Concentration Calculation Using Two-wavelength Scanning Lidar System (두파장 스캐닝 라이다 시스템을 이용한 고해상도 미세먼지 질량 농도 산출)

  • Noh, Youngmin;Kim, Dukhyun;Choi, Sungchul;Choi, Changgi;Kim, TaeGyeong;Kim, Gahyeong;Shin, Dongho
    • Korean Journal of Remote Sensing
    • /
    • v.36 no.6_3
    • /
    • pp.1681-1690
    • /
    • 2020
  • A scanning lidar system has been developed. The system has two wavelength observation channels of 532 and 1064 nm and is capable of 360-degree horizontal scanning observation. In addition, an analysis method that can classify the measured particle as an indicator of coarse-mode particle (PM2.5-10) and an indicator of fine-mode particles (PM2.5) and calculate the mass concentration of each has been developed by using the backscatter coefficient at two wavelengths. It was applied to the data calculated by observation. The mass concentrations of PM10 and PM2.5, which showed a distribution of 22-110 ㎍/㎥ and 7-78 ㎍/㎥, respectively, were successfully calculated in the Ulsan Onsan Industrial Complex using the developed scanning lidar system. The analyzed results showed similar values to the mass concentrations measured on the ground around the lidar observation area, and it was confirmed that high concentrations of 80-110 ㎍/㎥ and 60-78 ㎍/㎥ were measured at points discharged from factories, respectively.