• Title/Summary/Keyword: observation analysis

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Field Observation and Analysis of Wind-Induced Vibrations in Four-Bundled Conductor Transmission Lines

  • Sohn, Hong-Kwan;Lee, Hyung-Kwon;Chu, Jang-Hee;Lee, Dong-Il;Lee, Eun-Woong
    • KIEE International Transactions on Power Engineering
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    • v.3A no.2
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    • pp.109-114
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    • 2003
  • This paper presents observations made on four-bundled conductor transmission lines concerning the behavior of conductors under the effect of natural winds. To know the wind-induced vibration status and how to control it, wind-induced vibrations have been recorded and analyzed from the real transmission lines. From the field observation and analysis results, subspan oscillation was found to be the main type of vibration. In addition, the data also revealed some common characteristics of the observation sites with high maintenance rates. The results will be used in controlling the subspan oscillations and protecting the conductors.

Variations in Air Temperature and Water Temperature with Tide at the Intertidal Zone : Odo Island, Yeosu (조간대에서 조위에 따른 기온과 수온 변화 : 여수 오도섬)

  • Won Gi Jo;Dong-hwan Kang;Byung-Woo Kim
    • Journal of Environmental Science International
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    • v.31 no.12
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    • pp.1027-1038
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    • 2022
  • The intertidal zone has both land and marine characteristics and shows complex weather environments. These characteristics are suited for studying climate change, energy balance and ecosystems, and may play an important role in coastal and marine weather prediction and analysis. This study was conducted at Odo Island, approximately 300m from the mainland in Yeosu. We built a weather observation system capable of real-time monitoring on the mud flat in the intertidal zone and measured actual weather and marine data. Weather observation was conducted from April to June 2022. The results showed changes in air temperature and water temperature with changes in the tide level during spring. Correlation analysis revealed characteristic changes in air temperature and water temperature during the day and night, and with inundation and exposure.

An Analysis of Pre-service Elementary School Teachers' Degree of Preferences in Observation of Living Things in Pre and Post Laboratory Lessons (초등예비 교사의 실험 수업 전, 후 생물 관찰에 대한 선호도 분석)

  • Park, Kang-Eun
    • Journal of Korean Elementary Science Education
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    • v.35 no.2
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    • pp.216-228
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    • 2016
  • The purpose of this study was to analyze pre-school teachers' observation experience and their pre and post degrees of preferences in observing underground and water living things, fungus, insects, flowerless plants and sea lives. Based on the analysis, their pre-observation experience in living things were insects, ocean creatures, underground living things, flowerless plants, fungus and water living things in order. The degree of preferences in flowerless plans based on their gender, the female pre-service teachers showed higher scores than the average in both pre and post test. The male, however, responded higher scores in underground living things in both tests. Their background such as liberal arts or science or arts and physical major affected their preferences scores in water living things, insects and flowerless plans in the post test, and the science major pre-service teachers showed the highest degree of preferences in insects among the liberal arts, science or arts and physical major pre-teachers in the post test. In conclusion, there were different degree of their preferences affected by the pre observation experience, gender difference, their present majors such as the liberal arts, science or arts and physical major, the categories of living things but not in their high school background such as liberal arts or science.

An Analysis of Meanings and Processes about Scientific Observation in the Science Education (과학교육에서 제시하는 과학적 관찰의 의미와 과정에 대한 분석)

  • Byeon, Jung-Ho;Lee, Jun-Ki;Kwon, Yong-Ju
    • Journal of The Korean Association For Science Education
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    • v.29 no.5
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    • pp.531-540
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    • 2009
  • The purpose of this study is to investigate the meaning and process of scientific observation. Hence, this study reviewed and discussed meanings and process of scientific observation described in philosophy, the philosophy of science and science education. Major researches on scientific observation are focused on a characteristic and type of scientific observation behavior. These research can suggest what is the characteristic of observation facts generated by observer. But it cannot show what is the meaning and process of scientific observation, it should be provide to students. According to the result in this study, scientific observation is affected by observer's subjective factors, such as experience, background knowledge, interpretation(not inference) and observation skill. All factor are integrated as an intellectual framework, and it is able to be changed by the observed facts. On the other hand, inference is excluded on scientific observation, but it have constantly affect on intellectual framework through feedback. This study on scientific observation provides a scaffold in various activities of scientific observation to be provided to students.

Time Series Analysis of Groundwater Level Change in the Chuncheon Area Groundwater Observation Network (시계열 분석을 이용한 춘천 지역 지하수관측망 수위변동 해석)

  • Mok, Jong-Koo;Jang, Bum-Ju;Park, Yu-Chul;Shin, Hye-Soo;Kim, Jin-Ho;Song, Se-Jeong;Hawng, Ga-Young
    • The Journal of Engineering Geology
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    • v.32 no.2
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    • pp.281-293
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    • 2022
  • Time series analysis was performed on data from 2009 to 2018 from the Chuncheon groundwater observation network to understand the characteristics of groundwater level fluctuations in the network. There are five observatories, all of which are installed in rock aquifers, and periodic inspections and management are performed by the relevant operating organization. Auto-correlation, spectral density, and cross-correlation analysis was performed.

Analysis of users of agricultural outlook information

  • Seungjee Hong;Ga Eul Kim;Seon Min Park;Sounghun Kim
    • Korean Journal of Agricultural Science
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    • v.49 no.4
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    • pp.885-895
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    • 2022
  • Since the supply and demand of agricultural products are unstable, which causes instability in farm income and consumer prices, the government has sought to mitigate the problems caused by unstable supply and demand by generating and providing agricultural outlook information. However, research should be carried out to increase the quality and utilization of agricultural observation information, because the value of agricultural observation information increases only when more users use this information and apply it to their decisions. In this study, a survey was conducted targeting producers and experts who are users or potential users of agricultural outlook information, and the results were analyzed through quantitative model, specifically importance-performance analysis (IPA) and analytic hierarchy process (AHP). The results show that improvement of promptness was required among the seven items evaluated with regard to agricultural outlook. Also, measures for dissemination of agricultural outlook information and the contents of outlook information should be improved to increase its use. If the quality level and use of agricultural observation information are increased by reflecting the results of the above analysis, decision-making on the supply and demand of agricultural products in Korea will be improved, and it is thought that it will be possible to increase farm household income and stabilize consumer prices through stabilization of supply and demand of agricultural products.

Numerical Analysis of Wintertime Air Pollution in East Asia Region Using Long-Range Transport Model

  • Jang, Eun-Suk
    • Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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    • v.4 no.2
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    • pp.103-110
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    • 2000
  • In order to understand the wintertime intermittent characteristics of the trans-boundary air pollutant transport observed in East Asia, a numerical simulation of the long-range transport of pollutants was applied using an atmospheric transport model(STEM-II). The numerical simulation was carried out for the entire month of January 1997 and specific atmospheric aerosol (including sulfate, nitrate, and other ion compounds0 observation data were compared from four observation sites(Cheju Island, Kanghwa Island, Dazaifu, and Fukue Island). The observation data revealed that concentration peaks were intermittently observed at 3 to 4-day intervals plus the four observation sites exhibited a very similar spatial variation. The horizontal and spatial scale of the heavily polluted air masses was analyzed based on numerical results. The mechanism of the intermittent transport of air pollutants was clearly explained by a comparison of the observed data with the numerical output. It was found that the wind pattern variations associated with the synoptic scale pressure system changes play an extremely important role in the transport of pollutants in this region.

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An Analysis of Runoff Characteristics at Creeks (소하천 유역의 유출변화 특성분석)

  • Jung, Jae-Wook;Yoon, Sei-Eui
    • Journal of the Korean Society of Hazard Mitigation
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    • v.1 no.2 s.2
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    • pp.75-83
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    • 2001
  • In this study, the maintenance problems were investigated through checking the creeks which were improved by close-to-nature river improvement technique. The characteristics of flow were measured at Changsa Creek in Suwon city. The computational results of numerical model with kinematic wave theory was evaluated through observation data about precipitation, velocity, and flow depth. Furthermore, SCS, Clark, and RRL models were compared to the actual observations. As a result, the kinematic wave theory's calculated peak time of discharge concentration occurred little earlier than the actual observation, but the tendency of hydrograph coincided with observation.

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Observation of Spatial and temporal variability of sea skin surface temperature by a Thermal Infrared Camera

  • Tamba, Sumio;Yokoyama, Ryuzo;Parkes, Isabelle;David, Llewellyn-Jones
    • Proceedings of the KSRS Conference
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    • 1998.09a
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    • pp.14-19
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    • 1998
  • The MUBEX (MUtsu Bay sea surface temperature validation EXperiment) campaign has been held from 1995 to 1997 in summer. During the MUBEX campaign, a thermal infrared camera (TIC) installed on a research vessel, which was also equipped with other various observation devices, was intensively used to observe microscopic structure of sea skin surface temperature (SSST) behavior. We have now a total number of 500,000 images observed by the TIC under various weather conditions, i.e., very calm or wavy sea condition, and clear, patchy or cloudy sky condition. In this paper, we show typical SSST patterns observed by the TIC, and describe the result of statistical analysis of SSST.

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Evaluation of the Harbor Operation Rate Considering Long Period Waves (장주기파를 고려한 항만 가동율의 평가)

  • 김규한
    • Journal of Ocean Engineering and Technology
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    • v.16 no.2
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    • pp.21-26
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    • 2002
  • In this study, the characteristics of long period waves are analyzed by field observation at Sokcho harbor on the eastern coast of Korea. firstly. the pressure data obtained from field observation are transformed into water surface elevations and the wave by wave analysis is applied to the observed wave data. also, we select long period waves by setting up the range 30-200sec, and suggest the relationship between ordinary waves and long period waves using the concept of the significant wave height. and, we examine the effects oft he long period waves on the rate of the harbor operation. The observation results demonstrate that the long period waves with heights of 1.2-14.6cm and periods of 35.8-162sec exist at Sokcho harbor. also, we found the rates of harbor operation based on long period waves are 61.8%-99.5% lower than the usual rates of 93.8%-100%.