• Title/Summary/Keyword: January

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Analysis of Variations in Soil Heat Flux and Air Temperature by Net Radiation at a Mud Flat in Hampyeong Bay (함평만 갯벌에서 순복사에 의한 토양열 플럭스와 기온의 변동 분석)

  • Park, Ho-seon;Kwon, Byung Hyuk;Kim, Il-Kyu;So, Yoon Hwan;Oh, Se Bong;Kang, Dong-hwan
    • Journal of Environmental Science International
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    • v.26 no.9
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    • pp.1101-1110
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    • 2017
  • In this study, we analyze changes in soil heat flux and air temperature in August (summer) and January (winter) according to net radiation, at a mud flat in Hampyeong Bay. Net radiation was observed as $-84.2{\sim}696.2W/m^2$ in August and $-79.4{\sim}352.5W/m^2$ in January. Soil heat flux was observed as $-80.7{\sim}139.5Wm^{-2}$ in August and $-49.09{\sim}137W/m^2$ in January. Air temperature was observed as $24.2{\sim}32.9^{\circ}C$ in August and $-1.5{\sim}11.1^{\circ}C$ in January. The rate of soil heat flux for net radiation ($H_G/R_N$) was 0.17 in August and 0.34 in January. Because the seasonal fluctuation in net radiation was bigger than the soil heat flux, net radiation in August was bigger than in January. We estimated a linear regression function to analyze variations in soil heat flux and air temperature by net radiation. The linear regression function and coefficient of determination for the soil heat flux by net radiation was y=0.19x-7.94, 0.51 in August, and y=0.39x-11.69, 0.81 in January. The time lag of the soil heat flux by net radiation was estimated to be within ten minutes in August 2012 and January 2013. The time lag of air temperature by net radiation was estimated at 160 minutes in August, and 190 minutes in January.

An Revisit On the Monthly Effect in Korean Stock Market (우리나라 증권시장의 일월효과 재검정)

  • Lee, Young-hwan;Yoon, Hong-Geun;Park, Kwang-Suck
    • Journal of Industrial Convergence
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    • v.7 no.1
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    • pp.63-82
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    • 2009
  • Many The purpose of this paper is to revisit the existence of monthly effect in the Korea Stock Market. We conducted additory test about KOSPI200 from January 1990 to December 2002 and about KOSDAQ from January 2002 to December 2006. The other main focus is examine Size Effect in Korean Stock Market. We also indicate Information hypothesis throught our findig. Data used in this paper are monthly returns of KOSPI and KOSDAQ from 1980 to 2006. As a result, Evidence is provided that monthly abnormal returns in January have large means relative to the remaining eleven months. The relation between abnormal returns and size is always negative and more pronounced in January than in any other month-even in years. More than fifty percent of the January premium is attributable to large abnormal returns during the first week of trading in the year particularly on the first trading day. This finding is highly significant in the mall sized capital stock of KOSPI market. We found January effect and Size Effect in the KOSPI market, but we didn't find January effect and Size Effect in the KOSDAQ market and KOSPI200.

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Seasonal Variation Studies and Pharmacognostic Evaluation of Alstonia scholaris R.Br. Bark

  • Upadhye, A.S.;Khatoon, Sayyada;Mehrotra, Shanta
    • Natural Product Sciences
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    • v.12 no.4
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    • pp.241-246
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    • 2006
  • Alstonia scholaris is known as 'Saptaparna' in Ayurvedic System of Medicines and the bark is used for the treatment of various diseases. It has various ethnomedicinal values as different traditional communities find diverse medicinal properties. The present communication deals with the seasonal variation studies of the stem bark of this plant. The bark was collected in the month of January, July and November. There is no macro-microscopical changes in all the three seasons but the ash values showed significant differences. Crude fibre content showed sharp decline from January to July to November. Total tannin percentage was found maximum in January and minimum in June. TLC finger print profile showed more concentration of constituents in January as compared to June and November. Hence, the bark may show more efficacy when collected in January.

Reproduction of the Shotted halibut in the southern Korean waters (한국 남해에 서식하는 물가자미, Eopsetta grigorjewi (Herzenstein)의 재생산 연구)

  • Cha, Hyung-Kee;Kang, Su-Kyung;Choi, Jung-Hwa;Oh, Taeg-Yun;Seo, Young-Il
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.47 no.3
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    • pp.194-202
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    • 2011
  • Maturation and spawning of the Shotted halibut, Eopsetta grigorjewi was investigated based on the samples captured in South Korean waters from January 2008 to December 2009. Gonadosomatic index began to increase in December, and reached maximum between January to March. After spawning it began to decrease from May. Reproductive season was estimated to January-April, with peak in February. Fecundity was proportional to the size of the female, with the clutch size varying from 170,000 eggs in the smallest female (total length, 28.9cm) to 1,300,000 eggs in the largest (total length, 41.5cm). Size at 50% sexual maturity (TL50), determined from mature females, was 28.8cm. Annual reproductive cycles of this species could be divided into six successive stages; immature stage (May-October), nucleolus stage (November-January), yolk vesicle stage (January-February), vitellogenic and ripe stage (January-April) and spent stage (April-May).

Analysis on the January Effect and Market Efficiency in Korea Stock Market Before and After IMF Financial Crisis (IMF 금융위기 전후 국내 주식시장의 1월효과 현상 및 효율성 분석)

  • Yun, Kang-In
    • The Journal of the Korea Contents Association
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    • v.17 no.3
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    • pp.578-588
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    • 2017
  • The purpose of this paper was to prove the January Effect and Efficiency of the KOSPI Market, and then suggest as a result. KOSPI data was divided into two of section, Before and After IMF Financial Crisis, and this paper utilized Market Capitalization of common stock to conduct a study. As the main findings of this result, in KOSPI 1st section(Before IMF Financial Crisis), this paper proved the January Effect and Size Effect for Small-capital stock. On the other hand, in KOSPI $2nd-{\alpha}$ & ${\beta}$ section(After IMF Financial Crisis), this paper couldn't prove the January Effect. And then, this paper couldn't prove the Efficient Market hypothesis in KOSPI 1st with January Effect, however, proved the weak efficient market in KOSPI 2nd(${\alpha}$ & ${\beta}$) without January Effect. Finally, this paper deducted implications and limitation as the results.

EC or TDS as a Water Pollution Criteria in Water Education Program (물환경 체험 및 탐구 활동에서 수질오염지표로서 전기전도도(EC) 혹은 총용존고형물질(TDS)의 활용에 대한 고찰)

  • Ahn, Samyoung
    • Journal of Environmental Science International
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    • v.31 no.4
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    • pp.341-356
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    • 2022
  • Electrical Conductivity (EC) or Total Dissolved Solids (TDS) has been often used to evaluate the water quality in some water education program for children and youth. This study attempted to find out whether EC (or TDS) can be used as a water pollution criteria in water education program. To clarify it, we used the water analysis data of July 2019 and January 2020 from Water Environment Information System. Data from 332 points in Han-river were used to investigate correlation between the parameters, such as BOD, COD, TN, TP vs EC. Correlation(r) for all data of BOD vs. EC was 0.347 for July 2019 and 0.483 for January 2020. No correlation was observed for BOD Ia and BOD Ib for July 2019 (r=-0.041, -0.030, respectively) and BOD Ia for January 2020 (r=0.041). Better correlation for all data of COD vs. EC was obtained (r=0.543 for July 2019 and r=0.610 for January 2020). However, no correlation was observed for COD Ia for January 2020. High vlaue of EC or TDS does not always mean water pollution, especially for clean water environment. Thus, EC (or TDS) alone can not be used as a water pollution criteria.

Maturity and Spawning of the Atka Mackerel, Pleurogrammus azonus (Jordan and Metz) in the East Sea (동해 임연수어, Pleurogrammus azonus (Jordan and Metz)의 성숙과 산란)

  • Lee, Sung-Il;Yang, Jae-Hyeong;Yoon, Sang-Chul;Chun, Young-Yull;Kim, Jong-Bin;Cha, Hyung-Kee;Chang, Dae-Soo;Kim, Jae-Won
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.42 no.6
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    • pp.633-641
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    • 2009
  • Maturity and spawning of the atka mackerel, Pleurogrammus azonus, was investigated based on the samples collected by gill net and set net in the East Sea from January 2006 to March 2009. Gonadosomatic index (GSI) began to increase in October, and reached a maximum between November and December. After spawning GSI began to decrease from January. The spawning period was from October to January, and main spawning period was from November to December. Annual reproductive cycles of this species could be divided into five successive stages in females; early growing stage (June), late growing stage (July to August), mature stage (September to October), ripe and spent stage (November to January), and recovery and resting stage (January to May). Males showed four successive stages: growing stage (June to August), mature stage (September to October), ripe and spent stage (October to December), and recovery and resting stage (January to May). P. azonus could be one of polycyclic species spawning two times or more during one spawning season. Number of total and mature eggs in the fecundity were proportional to fork length. The fork length at 50% group maturity was estimated to be 26.9 cm.

The Change of Seasonal Trend Appeared in Wintertime Daily Mean Temperature of Seoul, Korea (서울의 겨울철 일평균 기온에 나타난 계절 추이와 변화)

  • Park, Byong-Ik
    • Journal of the Korean Geographical Society
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    • v.46 no.2
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    • pp.152-167
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    • 2011
  • This study aims to investigate the change of seasonal trend appeared in the daily normals of wintertime daily mean temperature of Seoul for 1941~1970 and 1971~2000 and the factors to affect it. The lowest temperature in wintertime is appeared in the period of the first and second ten-days of January in the daily normals for 1941~1970 and in the third ten-days of January and the first ten-days of February for 1971~2000. This means seasonal trend was changed. This change is due to the fact average temperature from 27 December to 20 January is rising much more than the wintertime mean temperature and average temperature from 21 January to 9 February less than that for two daily normals. This features are notable after 1971. The Siberian high and norther wind around the Korean Peninsula are weakened remarkably recently, so mean temperature of Seoul from 27 December to 20 January is warming much more. On the other hand, the Siberian high from 21 January to 9 February is weakened and the Aleutian low is strengthened recently and northerly is not change obviously, so temperature of Seoul is not warming so much.

Aneurysms of Distal Posterior Inferior Cerebellar Artery

  • Park, Jong-Su;Lee, Tae-Hoon;Seo, Eui-Kyo;Cho, Yong-Jae
    • Journal of Korean Neurosurgical Society
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    • v.44 no.4
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    • pp.205-210
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    • 2008
  • Objective : Aneurysms are very rarely encountered in the distal posterior inferior cerebellar artery (PICA). The authors experienced 5 cases with a distal PICA aneurysm among 368 cases of intracranial aneurysms during the period from January 2003 to January 2008. Here, the authors describe their clinical and surgical experiences and include a review of the relevant literature. Methods : Using radiologic findings and charts, we retrospectively reviewed the surgical results of 5 cases with a distal PICA aneurysm treated from January 2003 to January 2008. Results : The current five cases were composed of four cases of 'Good' and one case of 'Fair'. No postoperative complications occurred other than a ventriculo-peritoneal shunt due to hydrocephalus in Case 2. In all five cases, treatment was successful without neurological deficit. Conclusion : Surgical outcome of PICA aneurysms have been reported to be excellent because the amount of intraparenchymal injury is limited. More clinical experience, microsurgical technique developments, and endovascular surgery advancements are certain to improve treatment outcomes.

Characteristic Features Observed in the East-Asian Cold Anomalies in January 2011 (2011년 1월의 동아시아 한랭 아노말리 특성)

  • Choi, Wookap;Jung, Jiyeon;Jhun, Jong-Ghap
    • Atmosphere
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    • v.23 no.4
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    • pp.401-412
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    • 2013
  • East Asia experienced extremely cold weather in January 2011, while the previous December and the following February had normal winter temperature. In this study National Centers for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) reanalysis data are used to investigate the characteristic features observed in the meteorological fields such as temperature, sea-level pressure, geopotential height, and wind during this winter period. In January the planetary-wave pattern is dominated by stationary-wave form in the mid-to-high latitude region, while transient waves are significant in the previous month. To understand the planetary-wave features quantitatively, harmonic analyses have been done for the 500-hPa geopotential height field. In the climatological-mean geopotential heights the wave numbers 1, 2, and 3 are dominant during the whole winter. In January 2011 the waves of number 1, 2, and 3 are dominant and stationary as in the climatological-mean field. In December 2010 and February 2011, however, the waves of number 4, 5, and 6 play a major role and show a transient pattern. In addition to the distinctive features in each month the planetary-wave patterns dependent on the latitude are also discussed.