• Title/Summary/Keyword: DTR

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Study on the Antitumor Activity of Dichloromethane Extract of Tripterygium regelii SPRAGUE (뇌공등(雷公藤) 디클로메탄(CH$_2$Cl$_2$)분획의 항암효능 연구)

  • Park, Wan-Su
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.20 no.5
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    • pp.1196-1199
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    • 2006
  • Tripterygium regelii SPRAGUE is distributed in Korea and Northern China. This extract has been used as a herb medicine, especially antiparasitic, anti-inflammatory and detoxifying agent in East asia. During our research to develop new antitumor agents from natural products, Dichlorornethane (CH$_2$Cl$_2$) extract of Tripterygium regelii SPRAGUE (DTR) showed the potent apoptotic effects in A-549 lung cancer, HeLa-3 cervical cancer, SKMEL-2 melanoma cells in a dose-dependent manner. in order to purify major compounds from DTR, column chromatography was carried out gradually. Silica gel and RP-18 column chromatography for active fractions led to the isolation of a compound. The compound determined by 1 H-NMR was turned out to De Celastrol known to have antitumor activity.

Spatial Distribution of Urban Heat Island based on Local Climate Zone of Automatic Weather Station in Seoul Metropolitan Area (자동기상관측소의 국지기후대에 근거한 서울 도시 열섬의 공간 분포)

  • Hong, Je-Woo;Hong, Jinkyu;Lee, Seong-Eun;Lee, Jaewon
    • Atmosphere
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    • v.23 no.4
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    • pp.413-424
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    • 2013
  • Urban Heat Island (UHI) intensity is one of vital parameters in studying urban boundary layer meteorology as well as urban planning. Because the UHI intensity is defined as air temperature difference between urban and rural sites, an objective sites selection criterion is necessary for proper quantification of the spatial variations of the UHI intensity. This study quantified the UHI intensity and its spatial pattern, and then analyzed their connections with urban structure and metabolism in Seoul metropolitan area where many kinds of land use and land cover types coexist. In this study, screen-level temperature data in non-precipitation day conditions observed from 29 automatic weather stations (AWS) in Seoul were analyzed to delineate the characteristics of UHI. For quality control of the data, gap test, limit test, and step test based on guideline of World Meteorological Organization were conducted. After classifying all stations by their own local climatological properties, UHI intensity and diurnal temperature range (DTR) are calculated, and then their seasonal patterns are discussed. Maximum UHI intensity was $4.3^{\circ}C$ in autumn and minimum was $3.6^{\circ}C$ in spring. Maximum DTR appeared in autumn as $3.8^{\circ}C$, but minimum was $2.3^{\circ}C$ in summer. UHI intensity and DTR showed large variations with different local climate zones. Despite limited information on accuracy and exposure errors of the automatic weather stations, the observed data from AWS network represented theoretical UHI intensities with difference local climate zone in Seoul.

Proximal Gastrectomy for Gastric Cancer

  • Jung, Do Hyun;Ahn, Sang-Hoon;Park, Do Joong;Kim, Hyung-Ho
    • Journal of Gastric Cancer
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    • v.15 no.2
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    • pp.77-86
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    • 2015
  • Laparoscopic proximal gastrectomy (LPG) is theoretically a superior choice of minimally-invasive surgery and function-preserving surgery for the treatment of proximal early gastric cancer (EGC) over procedures such as laparoscopic total gastrectomy (LTG), open total gastrectomy (OTG) and open proximal gastrectomy (OPG). However, LPG and OPG are not popular surgical options due to three main concerns: the first, oncological safety; the second, functional benefits; and the third, anastomosis-related late complications (reflux symptoms and anastomotic stricture). Numerous recent studies have concluded that OPG and LPG present similar oncological safety profiles and improved functional benefits when compared with OTG and LTG. While OPG with modified esophagogastrostomy does not provide satisfactory results, OPG with modified esophagojejunostomy showed similar rates of anastomosis-related late complications when compared to OTG. At this stage, no standard reconstruction method post-LPG exists in the clinical setting. We recently showed that LPG with double tract reconstruction (DTR) is a superior choice over LTG for proximal EGC in terms of maintaining body weight and preventing anemia. However, as there is no definitive evidence in favor of LPG with DTR, a randomized clinical trial comparing LPG with DTR to LTG was recommended. This trial, the Korean Laparoscopic Gastrointestinal Surgery Study-05 (NCT01433861), is expected to assist surgeons in choice of surgical approach and strategy for patients with proximal EGC.

Study on Thermal Load Capacity of Transmission Line Based on IEEE Standard

  • Song, Fan;Wang, Yanling;Zhao, Lei;Qin, Kun;Liang, Likai;Yin, Zhijun;Tao, Weihua
    • Journal of Information Processing Systems
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    • v.15 no.3
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    • pp.464-477
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    • 2019
  • With the sustained and rapid development of new energy sources, the demand for electric energy is increasing day by day. However, China's energy distribution is not balanced, and the construction of transmission lines is in a serious lag behind the improvement of generating capacity. So there is an urgent need to increase the utilization of transmission capacity. The transmission capacity is mainly limited by the maximum allowable operating temperature of conductor. At present, the evaluation of transmission capacity mostly adopts the static thermal rating (STR) method under severe environment. Dynamic thermal rating (DTR) technique can improve the utilization of transmission capacity to a certain extent. In this paper, the meteorological parameters affecting the conductor temperature are analyzed with the IEEE standard thermal equivalent equation of overhead transmission lines, and the real load capacity of 220 kV transmission line is calculated with 7-year actual meteorological data in Weihai. Finally, the thermal load capacity of DTR relative to STR under given confidence is analyzed. By identifying the key parameters that affect the thermal rating and analyzing the relevant environmental parameters that affect the conductor temperature, this paper provides a theoretical basis for the wind power grid integration and grid intelligence. The results show that the thermal load potential of transmission lines can be effectively excavated by DTR, which provides a theoretical basis for improving the absorptive capacity of power grid.

Past and Future Temperature and Precipitation Changes over Korea using MM5 Model

  • Oh, Jai-Ho;Min, Young-Mi;Kim, Tae-Kook;Woo, Su-Min;Kwon, Won-Tae;Baek, Hee-Jeong
    • Proceedings of the Korean Quaternary Association Conference
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    • 2004.06a
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    • pp.29-29
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    • 2004
  • Long term observational analysis by climatologists has confirmedthat the global warming is no longer a topic of debate among scientists andpolicy makers. According to the report of IPCC-2001 (Intergovernmental Panelon Climate Change), the global mean surface air temperature is increasinggradually. The reported increase of mean temperature is by 0.6 degree in the end of twentieth century. This could represent severe threat for propertylosses especially due to increase in the number of extreme weather arising out of global warming. period of model integration from 2001 to 2100 using output of ECHAM4/HOPE-G of Max Planet Institute of Meteorology (MPI) for IPCC SRES (Special Report on Emission Scenarios). The main results of this study indicate increase of surface air temperature by 6.20C and precipitation by 2.6% over Korea in the end of 21st century. Simulation results also show that there is increase in daily maximum and minimum temperatures while decrease in diurnal temperature range (DTR). DTR changes are diminished mainly due to relatively rapid increase of daily minimum temperature than that of daily maximumtemperature. It has been observed that increase in precipitation amount anddecrease in the number of rainy days lead to increase of pre precipitationintensity.

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The Relocation Effect of Observation Station on the Homogeneity of Seasonal Mean of Diurnal Temperature Range (기상관측소의 이전이 계절평균 일교차의 균질성에 미치는 영향)

  • Kim, Ji-Hyun;Suh, Myoung-Seok;Hong, Soon-Hee
    • Atmosphere
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    • v.20 no.4
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    • pp.437-449
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    • 2010
  • The relocation effect of observation station (REOS) on the homogeneity of seasonal mean of maximum and minimum temperature, diurnal temperature range (DTR) and relative humidity (RH) was investigated using surface observation data and document file. Twelve stations were selected among the 60 stations which have been operated more than 30 years and relocated over one time. The data from Chunpungryeong station were used as a reference to separate the impacts of station relocation from the effects caused by increased green house gases, urbanization, and others. The REOS was calculated as a difference between REOS of relocated station and REOS of reference station. Although the REOS is clearly dependent on season, meteorological elements, and observing stations, statistically significant impacts are found in many stations, especially the environment of observing station after relocation is greatly changed. As a result, homogeneity of seasonal mean of meteorological elements, especially DTR and RH, is greatly reduced. The results showed that the effect of REOS, along with the effect of urbanization, should be eliminated for the proper estimation of climate change from the analysis of long-term observation data.

Evaluation of Electrical and Leakage Current Characteristics of Polymer Arrester(42kV 10kA Class3) for Railroad Line (전차선로용 폴리머 피뢰기(42kV 10kA Class3)의 전기적 특성 및 누설전류 특성 평가)

  • Kim, Seok-Sou;Choi, Ike-Sun;Park, Choon-Hyun;Cho, I-Gon;Park, Tae-Gon
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2004.07b
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    • pp.1171-1174
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    • 2004
  • Leakage current of the polymer arrester(42kV, 10kA, Class3) for railroad line applied actually field was observed and electrical characteristics of arrester before and after applied actually field were investigated. During applied actually field, leakage current of arresters were $610{\sim}647{\mu}A$ in AN SAN line and $500{\mu}A$ in YUNG DONG line. After applied actually field, electrical characteristics of arrester, such as insulation test, reference voltage test, leakage current test and partial discharge current test, wasn't variation as before applied actually field.

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Electrical Characteristics of ZnO Varistor for Transmission Class Arrester (송전급 피뢰기용 ZnO 바리스터 소자의 전기적 특성)

  • Kim, Seok-Sou;Park, Choon-Hyun;Cho, I-Gon;Park, Tae-Gon
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2004.04b
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    • pp.179-182
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    • 2004
  • ZnO varistor for transmission class arrester$({\Phi}65{\times}20mm)$ of 10kA(Class 3) grade was recently developed in korea and is tested for the properties by switching surge operating duty test to know the line discharge class and complex surge property in electric properties. To find out changing rate of residual voltage before and after lightning impulse residual voltage testing, the sample is cool to room temperature after finishing switching surge operating duty test, and the rate is good as 1.0~1.7%. The element had been considered as applicable ZnO varistor for electricity transmission from the test results of state conterl, switching surge operating duty, thermal stability and above test. But various test should be required for actual application because this is a part of the to be needed for application.

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Availability of the Pendulum Test Using NK Table for Spasticity Measurement of Low Extremity (하지 강직 평가에 있어 NK테이블을 이용한 진자검사의 유용성)

  • Kim, Yong-Wook;Weon, Jong-Hyuck;Kim, Tae-Ho
    • Journal of the Korean Society of Physical Medicine
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    • v.8 no.2
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    • pp.209-217
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    • 2013
  • PURPOSE: The purpose of this study was to investigate the clinical availability of the pendulum test (through reliability and validity) using a NK table attached electrogoniometer for spasticity measurement in patients with brain lesions. METHODS: Thirty-one stroke and traumatic brain injury subjects participated in the study. Intraclass correlation coefficient (ICC) was used to verify the test-retest reliability of spasticity measures of the pendulum test. Pearson's product correlation coefficient was used to examine the validity of the pendulum test through the amplitude of the deep tendon reflex (DTR) test known for objective and quantitative measure of spasticity. RESULTS: In these results, the test-retest reliability was showed significantly high correlation between pendulum tests (ICCs=.95~.97, p<.01). There were significant negative correlations between the amplitude of the DTR test and all measures of spasticity of the pendulum test(r=-.77~-.85, p<.01). CONCLUSION: Thus, it is possible to use the pendulum test using a NK table as an objective measure of spasticity, rather than other expensive equipment, which is more complicated to use. Further studies are needed to explore the therapeutic effects of spasticity using a newly designed pendulum test equipment in this study.

Combustion Characteristics for Co-firing of Biomass (Walnut Shell) (바이오매스(호두껍질) 혼소에 대한 연소 특성에 관한 연구)

  • Kim, Jin-Ho;Lee, Byoung-Hwa;Sh, Lkhagvadorj;Kim, Sang-In;Jeon, Chung-Hwan
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.39 no.1
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    • pp.53-59
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    • 2015
  • Combustion characteristics for co-firing of biomass (Walnut Shell) as blending fuel in coal fired boiler have investigated using thermogravimetric analyser (TGA) and drop tube reactor (DTR). The results show that devolatilization and char combustion for WS occurs at lower temperature than those of existing coals and has lower activation energy value, which is resulting in higher reactivity. When the WS is blended with coal, TGA results show linear profiles depending on blending ratio for each fuel. However, DTR results exist the non-additive phenomena for blending of WS. As blending ratio of WS increase, the UBC decrease at BBR 5%, but the UBC rather increase from BBR 10% due to oxygen deficiency formed from rapid combustion of WS. This paper propose that fuel lean condition by oxygen rich lead to higher blending ratio of biomass by solving the oxygen deficiency condition.