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A Comparative Study on General Circulation Model and Regional Climate Model for Impact Assessment of Climate Changes (기후변화의 영향평가를 위한 대순환모형과 지역기후모형의 비교 연구)

  • Lee, Dong-Kun;Kim, Jae-Uk;Jung, Hui-Cheul
    • Journal of Environmental Impact Assessment
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    • v.15 no.4
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    • pp.249-258
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    • 2006
  • Impacts of global warming have been identified in many areas including natural ecosystem. A good number of studies based on climate models forecasting future climate have been conducted in many countries worldwide. Due to its global coverage, GCM, which is a most frequently used climate model, has limits to apply to Korea with such a narrower and complicated terrain. Therefore, it is necessary to perform a study impact assessment of climate changes with a climate model fully reflecting characteristics of Korean climate. In this respect, this study was designed to compare and analyze the GCM and RCM in order to determine a suitable climate model for Korea. In this study, spatial scope was Korea for 10 years from 1981 to 1990. As a research method, current climate was estimated on the basis of the data obtained from observation at the GHCN. Future climate was forecast using 4 GCMs furnished by the IPCC among SRES A2 Scenario as well as the RCM received from the NIES of Japan. Pearson correlation analysis was conducted for the purpose of comparing data obtained from observation with GCM and RCM. As a result of this study, average annual temperature of Korea between 1981 and 1990 was found to be around $12.03^{\circ}C$, with average daily rainfall being 2.72mm. Under the GCM, average annual temperature was between 10.22 and $16.86^{\circ}C$, with average daily rainfall between 2.13 and 3.35mm. Average annual temperature in the RCM was identified $12.56^{\circ}C$, with average daily rainfall of 5.01mm. In the comparison of the data obtained from observation with GCM and RCM, RCMs of both temperature and rainfall were found to well reflect characteristics of Korea's climate. This study is important mainly in that as a preliminary study to examine impact of climate changes such as global warming it chose appropriate climate model for our country. These results of the study showed that future climate produced under similar conditions with actual ones may be applied for various areas in many ways.

PRELIMINARY FEASIBILITY STUDY OF THE SOLAR OBSERVATION PAYLOADS FOR STSAT-CLASS SATELLITES

  • Moon, Yong-Jae;Cho, Kyung-Seok;Jin, Ho;Chae, Jong-Chul;Lee, Sung-Ho;Seon, Kwang-Il;Kim, Yeon-Han;Park, Young-Deuk
    • Journal of Astronomy and Space Sciences
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    • v.21 no.4
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    • pp.329-342
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    • 2004
  • In this paper, we present preliminary feasibility studies on three types of solar observation payloads for future Korean Science and Technology Satellite (STSAT) programs. The three candidates are (1) an UV imaging telescope, (2) an UV spectrograph, and (3) an X-ray spectrometer. In the case of UV imaging telescope, the most important constraint seems to be the control stability of a satellite in order to obtain a reasonably good spatial resolution. Considering that the current pointing stability estimated from the data of the Far ultraviolet Imaging Spectrograph (FIMS) onboard the Korean STSAT-1, is around 1 arc minutes/sec, we think that it is hard to obtain a spatial resolution sufficient for scientific research by such an UV Imaging Telescope. For solar imaging missions, we realize that an image stabilization system, which is composed of a small guide telescope with limb sensor and a servo controller of secondary mirror, is quite essential for a very good pointing stability of about 0.1 arcsec. An UV spectrograph covering the solar full disk seems to be a good choice in that there is no risk due to poor pointing stability as well as that it can provide us with valuable UV spectral irradiance data valuable for studying their effects on the Earth's atmosphere and satellites. The heritage of the FIMS can be a great advantage of developing the UV spectrograph. Its main disadvantage is that two major missions are in operation or scheduled. Our preliminary investigations show that an X-ray spectrometer for the full disk Sun seems to be the best choice among the three candidates. The reasons are : (1) high temporal and spectral X-ray data are very essential for studying the acceleration process of energetic particles associated with solar flares, (2) we have a good heritage of X-ray detectors including a rocket-borne X-ray detector, (3) in the case of developing countries such as India and Czech, solar X-ray spectrometers were selected as their early stage satellite missions due to their poor pointing stabilities, and (4) there is no planned major mission after currently operating Reuven Ramaty High-Energy Solar Spectroscopic Imager (RHESSI) mission. Finally, we present a preliminary design of a solar X-ray spectrometer covering soft X-ray (2 keV) to gamma ray (10 MeV).

Risk of Bradycardia and Temperature Changes during Thoracic Sympathicotomy for Hyperhidrosis under Total Intravenous Anesthesia with Propofol (Propofol 전정맥 마취하에 흉부 교감신경 절단술 시 서맥의 위험성과 온도 변화)

  • Chung, Chong-Kweon;Han, Jeong-Uk;Kim, Tae-Jung;Lee, Choon-Soo;Cha, Young-Deog;Lim, Hyun-Kyoung;Hu, I-Hoi;Yoon, Yong-Han;Kwak, Young-Lan
    • The Korean Journal of Pain
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    • v.14 no.2
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    • pp.181-185
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    • 2001
  • Background: Bradycardia frequently occurs in intravenous anesthesia with propofol. Additionally, the thoracic sympathetic nerves influence the heart so that the heart rate (HR) and blood pressure are expected to decrease due to this procedure. Therefore, we measured changes in HR, mean arterial pressure (MAP) and both thumb temperatures before and after thoracic sympathicotomy under total intravenous anesthesia with propofol. Methods: The subjects included 21 outpatients of ASA class I who received thoracoscopic thoracic sympathicotomy under total intravenous anesthesia. Anesthesia was induced with propofol (2 mg/kg) and vecuronium (0.1 mg/kg) and maintained with propofol-fentanyl-oxygen (100%). The surgical procedure was performed at the T3 level in the order of left sympathicotomy (LST) and right sympathicotomy (RST). Measurements of HR, MAP and both thumb temperatures were taken before induction of anesthesia, before and after LST and RST, and 1 hour after the completion of anesthesia. Additionally, the time to the beginning of a rise in temperature in both thumbs after sympathicotomy was recorded. Results: HR did not show any significant difference before or after sympathicotomy, however it decreased at 1 hour after the completion of anesthesia. MAP decreased after LST and decreased further after RST. Left thumb temperature began to increase at $45.8{\pm}10.7$ seconds after LST. Right thumb temperature initially decreased after LST and increased from $45.2{\pm}11.8$ seconds after RST. Subsequently, both increased temperatures were maintained at 1 hour after the completion of anesthesia. Conclusions: Although HR and MAP decreased, there were no severe hemodynamic changes. An increase in the thumb temperature was confirmed within 1 minute after sympathicotomy on the same side.

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An Analysis of Trends in Quantitative Studies on Female North Korean Refugees (탈북여성 관련 양적 연구동향 분석)

  • Lee, Soon Min;Shim, Woochan
    • The Journal of the Korea Contents Association
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    • v.18 no.7
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    • pp.470-483
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    • 2018
  • This study was conducted to analyze the trend of quantitative research regarding female North Korean refugees in order to broaden our understanding of North Korean women and provide directions for future research. In August 2017, the Korean studies Information Service System (KISS) and Nuri Media (DBpia) databases were used to search academic peer reviewed journal articles with the following keywords: "North Korean female", "North Korean female refugees" and "North Korean female defectors". Trend analysis included a content analysis of the study finding section, along with analysis of the general characteristics of the study such as published journals, year of publication, study methodologies, and subject of the study. The main findings are as follows: First, Korean Journal of Woman Psychology was the journal with the most studies on female North Korean refugees. Second, as a result of looking at research trends by year, there was only one study on North Korean female refugees published between 2000 and 2004, and the number started to increase in 2010(8 articles, 22.22%). Third, according to the analysis of research trends by research methods, survey method was most frequently used. Fourth, statistical analysis was most often utilized analysis methodology(34 studies, 94.44%). Fifth, in the content analysis, North Korean female refugees' mental health and emotional issues(17 studies, 47.22%) were the most often the focus of studies being analyzed, followed by social adjustment issues((5 studies, 13.89%). Based on these results, directions for future studies were suggested.

A Reduction Effect in Noise Reflection by Different Shapes of Soundproofing-panel (도로소음원에 대한 방음패널 형상별 반사소음 저감효과)

  • Kim, Ilho;Park, Taeho;Chang, Seoil;Lee, Haein
    • Journal of Korean Society of Environmental Engineers
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    • v.37 no.2
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    • pp.120-125
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    • 2015
  • With rapid urbanization, the volume of traffic in urban area has been significantly increased. This in turn led to problem which can be described as Road Traffic Noise. Currently, to alleviate the road traffic noise damage, a demand for installation of soundproofing walls is rising. Among different shapes of soundproof walls being installed, the reflection-type acoustical insulation panel is highly drawing attentions of residents due to the fact that it does not obstruct their field of vision in contrast with the opaque acoustical insulation panel. On the other hand, improving the soundproofing wall of the reflection-type acoustical insulation barrier panel needs to be focused on since it has a possibility to cause a secondary damage by reflected sounds. Therefore, in this research, study has been carried out to improve the forms in order to minimize travelling of reflected sounds through changing the frontal surface shape and geometrical shape of the reflection-type soundproofing panel. A result from comparison between the normal reflection-type soundproofing panel and the improved soundproofing panel, with reduction effects in the noise reflection, showed that the curved type of soundproofing panel has an impact on reducing the noise up to 1.5 dB. Furthermore, from the research conducted, it appears that the increase and decrease in the reflected sounds can be changeable depending on various design factors. Thus, it turns out that the study shows a potential possibility to develop a reduction technology of the reflected sounds pertaining to overall condition on the soundproofing walls.

Inclusive Impact Index "Triple I" for Assessing Ocean Utilization Technologies (해양이용기술 평가를 위한 포괄적 영향지수 "트리플 I")

  • Otsuka, Koji
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.15 no.2
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    • pp.118-125
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    • 2012
  • World population has increased rapidly following the industrial revolution, reaching 7 billion in 2012. Several forecasts estimate that this number will rise to about 8 billion in 2025. Improvements of living standards in developing nations have also raised resource and energy demands worldwide. In consequences, human beings have faced many global and urgent problems, such as global warming, water and food shortages, resource and energy crises, and so on. Many ocean utilization technologies for avoiding or reducing such big problems have been developed, for examples $CO_2$ ocean sequestration, seawater desalination, artificial upwelling, deepwater mining, and ocean energies. It is important, however, to assess such technologies from the viewpoints of sustainability and public acceptancy, since the aims of those technologies are to develop sustainable social systems rather than conventional ones based on fossil resources. Inclusive Marine Pressure Assessment and Classification Technology Research Committee (generally called IMPACT Research Committee) of Japan Society of Naval Architects and Ocean Engineers, has proposed Inclusive Impact Index "Triple I" as an indicator, which can predict both environmental sustainability and economical feasibility, in order to assess the ocean utilization technologies from the viewpoints of sustainability and public acceptancy. This index was considered by combining Ecological Footprint and Environmental Risk Assessment. The Ecological Footprint and the Environmental Risk Assessment are introduced in the first part of this paper. Then the concept and the structure of the Triple I are explained in the second part of this paper. Finally, the economy-ecology conversion factor in Triple I accounting is considered.

A Two-Phase Hybrid Stock Price Forecasting Model : Cointegration Tests and Artificial Neural Networks (2단계 하이브리드 주가 예측 모델 : 공적분 검정과 인공 신경망)

  • Oh, Yu-Jin;Kim, Yu-Seop
    • The KIPS Transactions:PartB
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    • v.14B no.7
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    • pp.531-540
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    • 2007
  • In this research, we proposed a two-phase hybrid stock price forecasting model with cointegration tests and artificial neural networks. Using not only the related stocks to the target stock but also the past information as input features in neural networks, the new model showed an improved performance in forecasting than that of the usual neural networks. Firstly in order to extract stocks which have long run relationships with the target stock, we made use of Johansen's cointegration test. In stock market, some stocks are apt to vary similarly and these phenomenon can be very informative to forecast the target stock. Johansen's cointegration test provides whether variables are related and whether the relationship is statistically significant. Secondly, we learned the model which includes lagged variables of the target and related stocks in addition to other characteristics of them. Although former research usually did not incorporate those variables, it is well known that most economic time series data are depend on its past value. Also, it is common in econometric literatures to consider lagged values as dependent variables. We implemented a price direction forecasting system for KOSPI index to examine the performance of the proposed model. As the result, our model had 11.29% higher forecasting accuracy on average than the model learned without cointegration test and also showed 10.59% higher on average than the model which randomly selected stocks to make the size of the feature set same as that of the proposed model.

Traffic Vulnerability Analysis of Rural Area using Road Accessibility and Functionality in Cheongju City (도로 접근성과 기능성을 이용한 통합청주시 농촌지역의 교통 취약성 분석)

  • Jeon, Jeongbae;Oh, Hyunkyo;Park, Jinseon;Yoon, Seongsoo
    • Journal of Korean Society of Rural Planning
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    • v.21 no.2
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    • pp.11-21
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    • 2015
  • This study carried out evaluation of vulnerability in accessability and functionality using road network that was extracted from Intelligent Transportation System(ITS) and digital map. It was built in order to figure out accessability that locational data which include community center, public facilities, medical facilities and highway IC. The method for grasping functionality are Digital Elevation Model(DEM) and land slide hazard map provided by Korea Forest Service. The evaluation criteria for figure out accessability was set to related comparison of average time in urban area. Functionality value was calculated by the possibility of backing the vehicle possibility of snowfall and landslides. At last, this research computed weighting value through Analytic Hierarchy Process (AHP), calculated a vulnerable score. As the result, the accessability of rural village came out that would spend more time by 1.4 to 3.2 times in comparison with urban area. Even though, vulnerability of the road by a snowfall was estimated that more than 50% satisfies the first class, however, it show up that the road were still vulnerable due snowing because over the 14% of the road being evaluated the fifth class. The functionality has been satisfied most of the road, however, It was vulnerable around Lake Daechung and Piban-ryung, Yumti-jae, Suriti-jae where on the way Boeun. Also, the fifth class road are about 35 km away from the city hall on distance, take an hour to an hour and a half. The fourth class road are about 25 km away from the city hall on distance, take 25 min to an hour. The other class of the road take in 30 min from the city hall or aren't affected of weather and have been analyzed that a density of road is high. In A result that compare between distribution and a housing density came out different the southern and the eastern area, so this result could be suggested quantitative data for possibility of development.

High Throughput-compatible Screening of Anti-oxidative Substances by Insect Extract Library (약용곤충추출물 라이브러리를 이용한 항산화 활성의 초고속 검색)

  • Park, Ja-Young;Heo, Jin-Chul;An, Sang-Mi;Yun, Eun-Young;Han, Sang-Mi;Hwang, Jae-Sam;Kang, Seok-Woo;Yun, Chi-Young;Lee, Sang-Han
    • Food Science and Preservation
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    • v.12 no.5
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    • pp.482-488
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    • 2005
  • Oxidant stress is well-known for a pivotal parameter related to neuro-inflammatory diseases including Alzheimer's disease, Parkinson's disease, and ALS (Lou Gehrig's disease). In order to effectively screen for anti-inflammatory agents, we first established the infrastructure of high throughput screening for anti-oxidant agents from medicinal insect library extracted with water, methanol, ethanol, and dimethyl sulfoxide. By the screening system, we found that Tenodera angustipennis Saussure, Pyrocoela rupa Olivier and Papilio maackii Mntris had strong anti-oxidant activity. Moreover, Tenodera angustipennis Saussure and Tenodera aridifolia (Stoll) exhibited protection effects of cellular damage by treatment of an oxidant hydrogen peroxide. Together, the results suggest that some selected hits could be a potential agent against neuro-inflammation, although the in vivo studies should be clearly tested.

Step-Coverage Consideration of Inter Metal Dielectrics in DLM Processing : PECVD and $O_3$ ThCVD Oxides (이층 배선공정에서 층간 절연막의 층덮힘성 연구 : PECVD와 $O_3$ThCVD 산화막)

  • Park, Dae-Gyu;Kim, Chung-Tae;Go, Cheol-Gi
    • Korean Journal of Materials Research
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    • v.2 no.3
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    • pp.228-238
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    • 1992
  • An investigation on the step-coverage of PECVD and $O_3$ ThCVD oxides was undertaken to implement into the void-free inter metal dielectric planarization using multi-chamber system for the submicron double level metallization. At various initial aspect ratios the instantaneous aspect ratios were measured through modelling and experiment by depositing the oxides up to $0.9{\mu}m$ in thickness in order to monitor the onset of void formation. The modelling was found to be in a good agreement with the observed instantaneous aspect ratio of TEOS-based PECVD oxide whose re-entrant angle was less than $5^{\circ}$. It is demonstrated that either keeping the instantaneous aspect ratio of PECVD oxide as a first layer less than a factor of 0.8 or employing Ar sputter etch to create sloped oxide edge ensures the void-free planarization after$O_3$ ThCVD oxide deposition whose step-coverage is superior to PECVD oxide. It has been observed that $O_3$ ThCVD oxide etchback scheme has shown higher yield of via contact chain than non etchback process, with resistance per via contact of $0.1~0.3{\Omega}/{\mu}m^2$.

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