• Title/Summary/Keyword: occurrence period

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Occurrence Characteristics of Marine Accidents Caused by Typhoons around Korean Peninsula

  • Yang Han Su;Kim Yeon Gyu
    • Journal of Navigation and Port Research
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    • v.29 no.2
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    • pp.151-157
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    • 2005
  • During the period of every summer to early autumn seasons, ships have been wrecked or grounded from effect of a typhoon in the water areas around Korean Peninsula Typhoon Rusa killed more than 100 people in September 2002. Super Typhoon Maemi passed southeast of South Korea in September 12-13, 2003, with a strong gale blowing at a record 60 m/s and caused much ship groundings, collisions and sinkings over 3000 in dockyards, harbors and places of refuge. These are things that could have been prevented had there merely been prior warning. This study outlines the occurrence characteristics of maritime accidents caused by a typhoon in South Korea for the period from 1962 to 2002. The distribution of the accident records is also compared with the trajectories, winds, central pressures of typhoons, passed during the 1990-2003. It is shown that attack frequency of typhoon and number of marine accidents is the highest in August and the marine accidents due to typhoon have a close relation to the distribution of accumulated wind and pressure fields.

Cultural characteristics and consumer acceptance of Pleurotus pulmonarius (산느타리버섯 재배특성 및 기호도 조사)

  • Lee, Kwang-Jae;Kim, Kyoung-Hee;Cho, Byung-Ju;Park, Young-Hak
    • Journal of Mushroom
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    • v.6 no.3_4
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    • pp.146-149
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    • 2008
  • Pleurotus pulmonarius usually grows on the dead wood of deciduous trees in mid summer to early fall. The pileus color is white to tan and fruiting body is generally smaller than P. ostreatus. This study was carried out to investigate the characteristics of cultivation and consumer acceptance of P. pulmonarius. The period of incubation and primordial occurrence were required about 33days, 5days in bottle cultivation repectively, and the yield was 170g/850cc bottle. In bed cultivation, the period of primordial occurrence was similar to that of bottle cultivation and the yields was $35.7{\sim}46.2kg/3.3m^2$. Taste and favor of P. pulmonarius were superior to P. oostreatus., but the appearance, color and shape, was slightly inferior to P. ostreatus.

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Recurrent dipolarizations of near-Earth magnetotail during high-speed solar wind streamers

  • Lee, En-Sang;Parks, George K.;Wilber, Mark;Lin, Naiguo;Lee, Dae-Young;Kim, Khan-Hyuk
    • The Bulletin of The Korean Astronomical Society
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    • v.36 no.2
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    • pp.94.1-94.1
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    • 2011
  • Recurrent substorms occur when high-speed solar wind streamers pass by Earth's magnetosphere. Most of the previous researches have been done using the observations obtained at the geosynchronous orbit focusing on the relationship between the solar wind disturbances and the occurrence of substorms. However, it is important to investigate the dynamics of the magnetotail because the magnetotail is the place where substorms develop. In this study we investigated the observations of recurrent dipolarizations in the near-Earth magnetotail that occurred during high-speed solar wind streamers. The dipolarizations and subsequent stretchings have occurred for more than three days with the average period of ~2 - 3 hours. The average period of ~2 - 3 hours is consistent with the average occurrence period of recurrent substorms. Also, the observed signatures on the geosynchronous orbit and the ground show recurrent substorms have occurred during the event. These suggest that the recurrent dipolarizations in the near-Earth magnetotail should be closely related to the recurrent substorms. On the other hand, there was no clear flow activities directly associated with the dipolarizations, except for some intermittent bursty flow activities. We will discuss the detailed characteristics of the dipolarizations and the relationship with recurrent substorms.

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Population Dynamics of Jellyfish Aurelia aurita (s.l.) in Sihwa Lake (시화호에서 보름달물해파리 Aurelia aurita (s.l.)의 개체군변동)

  • Hong, Hyun-Pyo;Han, Chang-Hoon;Yoo, Jeong-Kyu
    • Ocean and Polar Research
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    • v.35 no.3
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    • pp.205-217
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    • 2013
  • We investigated the population dynamics of Aurelia aurita in Sihwa Lake from April to October in 2009. Salinity ranged from 5.9 to 30.7 psu at the surface. Abundance of mesozooplankton ranged from 3 to 111,874 indiv. $m^{-3}$. Ephyrae occurred from April to May with the peak in abundance occurring on 17 April. Maximum density of ephyrae was observed near the power transmission towers that are known to be habitats of polyps. Mortality of ephyrae was lower than in other areas because of the abundant prey concentration and the absence of predators. Young medusae occurred from April to July with the peak in abundance occurring on 8 May. Adult medusae occurred from May to July with the peak in abundance on 25 June and they disappeared before the rainy season. Planula occurred only in May and June with the peak in abundance on 25 June. Growth rates of Aurelia aurita ranged from -0.06 to 0.34 $d^{-1}$, and decreased rapidly after May. The period in which adult medusa occurred was restricted, compared with those in other area in Korea (e.g., Masan Bay) and Japan (e.g., Tokyo Bay). In the period of this study, the available food was limited in June and salinity decreased to ca. 20 psu in May because of the beginning of the wet season. We assumed that the exceptionally short period of occurrence of the medusa may be a response of adults to changes in temperature, salinity or food limitation which leads to the precocious maturation of young medusa and the release of planula and that the brief occurrence of medusa was caused by an abrupt decrease in activity after the release of planula.

Effect of Herbal Medicines Including Licorice on Serum Potassium Levels (감초가 포함된 한약 복용 시 혈중 포타슘 수치의 저하에 영향을 미치는 요인)

  • Bae, Jeong-Hwa;Kim, Jung-Tae;Chung, Sung-Hyun
    • Korean Journal of Clinical Pharmacy
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    • v.22 no.2
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    • pp.153-159
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    • 2012
  • Licorice is a very useful herbal medicine frequently prescribed, but glycyrrhizin, one of its components, can cause pseudoaldosteronism presenting hypokalemia, metabolic alkalosis and hypertension as a result of prolonging a biological half-life of systemic steroid by strongly inhibiting the enzyme $11{\beta}$-hydroxysteroid dehydrogenase type 2. The risk factors for this side effect are still unclear. Here, 479 hospitalized patients taking herbal medicines including licorice for more than five days were recruited to analyze their serum potassium levels, under following parameters ; age and gender of patient, dose and period of licorice, disease state such as hypertension and with or without diuretics. They were divided into the non-occurrence group (over 3.5 mEq/L) and the occurrence group (under 3.5 mEq/L) of hypokalemia based on serum potassium levels during hospitalization. The average ages of the non-occurrence group and the occurrence group were $52.6{\pm}17.8$ and $68{\pm}10.5$, respectively (p < 0.001). But there were no noticeable differences in the daily dose of licorice, days of taking, and total dose between groups. Regression analysis showed that odd ratio of age (>60) and taking diuretics inducing hypokalemia was 3.5 (95%CI 1.5-8.1), 4.6 (95%CI 2.0-10.9) that indicates significant correlation with hypokalemia. Based upon this analysis, it is imperative to monitor regularly the risk of pseudoaldosteronism or hypokalemia not only when administered licorice of high dose for long period but also when combined it with diuretics causing hypokalemia to the elderly patients over 60 year old.

On the Characteristics of Probability and Periodicity for the Daily Precipitaty Occureonce in Korea (우리나라 일별 강수발생의 확률과 주기성의 특성)

  • Moon, Sung-Euii;Kim, Baek-Jo;Ha, Chang-Hwan
    • Journal of Environmental Science International
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    • v.6 no.2
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    • pp.95-106
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    • 1997
  • The characteristics on the transtion probabilities and periodicity for the daily precipitation occurrence in Korean peninsula are investigated by applying the Markov chain properties to daily precipitation occurrence. In order to examine the responses of Markov Chain properties to the applied period and their magnitudes, three cases (Case A: 1956~ 1985 at 14 stations, Case B: 1965~ 1994 at 14 stations, and Case C: 1985~ 1994 at 63 stations) are considered In this study. The transition probabilities from wet day to wet day for all cases are about 0.50 and in summer, especially July, are higher. In addition, considering them in each station we can find that they are the highest at Ullung-do and lowest at Inchon for all cases. The annual equilibrium probabilities of a wet day appear 0.31 In Case A, 0.30 Case B, and 0. 29 Case C, respectively. This may explain that as the data-period used becomes shorter, the higher the equilibrium probability is. The seasonal distributions of equilibrium probabilities are appeared the lowest(0.23~0.28) in winter and the highest(more than 0.39) in spring and monthly in .truly and in October, repectively. The annual mean wet duration for all cases is 2.04 days in Case A, 1.99 Case B, and 1.89 Case C, repectively. The weather cycle obtained from the annual mean wet and dry duration is 6.54~6.59 days, which are closely associated with the movement of synoptic systems. And the statistical tests show that the transitions of daily precipitation occurrence for all cases may have two-state first Markov chain property, being the stationarity in time and heterogeneity in space.

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Insect Pests Occurrence and Control in Organic and Conventional Rice Paddy Field (유기 및 관행벼 재배지 충해 발생 및 방제에 관한 연구)

  • Lee Sang-Guei;Lee Yong-Hoan;Kim Ji-Soo;Lee Byong-Mo;Kim Mi-Ja;Shin Jae-Hoon;Kim Han-Myeng;Choi Doo-Hoi
    • Korean Journal of Organic Agriculture
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    • v.13 no.3
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    • pp.301-314
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    • 2005
  • Insect pests were surveyed in 5 Rice paddy field areas of Organic paddy field and conventional paddy field. At the each rice-growth period, the occurrence rate of 'Small brawn plant hopper was high at the case of duck raising and rice bran farming on middle stage of rice paddy field in Gang-Hwa region. The occurrence rate of Rice water weevil was high at the conventional paddy field on the early stage of rice paddy field in Yeo-Ju region. In the Hong-Seong region, the occurrence rate of 'Rice water weevil' and 'Green rice leafhopper' was high at the 'duck raising compare to the conventional farming on the early stage of rice paddy field. According to each period, the occurrence rate of insect was high at late stage of rice paddy field, and there was no difference between each region. It showed high-occurrence tendency at duck pasture farming rice paddy field. The major natural enemies were spiders and parasites. Theridiidae and Linyphiidae were highly occurred on the conventional farming rice paddy field in Hong-Seong. Web builders containing Theridiidae, Linyphiidae and Tetragnathidae was occurred more than wandering spiders containing Lycosidae, Clubionidae and Pisauridae at various regions, and then occurrence of spiders was different at the various regions but was not different at each farming system.

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CLINICAL CHARACTERISTICS OF SECOND PRIMARY CANCER IN ORAL CANCER PATIENTS (구강암 환자에서 발생하는 이차암의 임상적 특징 분석)

  • Jo, Sae-Hyung;Shin, Jeong-Hyun;Lee, Ui-Ryoung;Park, Joo-Young;Choi, Sung-Weon
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.32 no.1
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    • pp.57-61
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    • 2010
  • Objective: Second primary malignancy (SPM) that occur in various period and region are important factors that deteriorate long-term survival rate in patients who recovered from oral cancer. Researches such as chemoprevention are being tried to reduce occurrence of SPMs. Only if analysis of clinical features of patients who develop SPM such as period, region and factors precedes, adequate prevention and treatment of SPM is possible. But, there are few researches about clinical features of SPMs that have primary lesion in oral cavity. In this study, we analysis that occurrence rates, regions that happen, risk factors and effect to survival rates of 2nd primary malignancies in oral cancer patients. From this survey, we willing to collect basic data for prevention and early diagnosis of SPMs. Methods: The medical records of 139 patients of oral oncology clinic of National Cancer Center who had up to 2-years follow up records after surgical or radiological treatment due to squamus cell carcinoma of oral cavity were reviewed. In these patients, survey of occurrence rate of SPMs, duration, survival rate and risk factors about occurrence of SPMs such as history of smoking, body mass index, age, sex, stage of primary lesion and history of radiologic treatment were achieved. Results: There are 15 patients who developed SPM in 139 cases. The actual occurrence rate of SPM was 10.79% and SPM were more likely to occur in male patients with 11 male Vs 4 female patients. Median age of these patient is 61.47 within 32 to 74 range. The regions that develop SPM are oral cavities (2 cases), stomach (4 cases), esophagus (2 cases), lung (2 cases) and others (1 case each breast, larynx, cervix, liver and kidney). In addition, metachronous cancers were 11 cases which happened more common than 4cases of synchronous cancers. Surveys of risk factors that relate to development of SPMs, such as sex, age, history of radiologic treatment, body mass index, history of smoking and stage of primary disease were done. Among them, factor of sex is only appear statistically significant (P=0.001), but rest are not significant in statistically. Conclusion: Occurrence rates of SPMs were reported from 10% to 20% by precede study. In this study, occurrence rate of SPMs is 10.79% that is similar to results of precede research. In comparison of 5-yr survival rates of groups that develop SPMs or not, there is statistically significance between two groups. Present treatment modalities of SPMs are surgical operation, radiotherapy, chemotherapy and combination of these modalities. In choosing the treatment modality, we must consider the first treatment modality, region of primary disease, region of SPMs and general conditions of patient. Because development of SPMs have big effect on prognosis, prevention of SPMs must regard to important objective of treatments in patients of SCCa in oral cavity.

Analysis of Regional Occurrence of Hail over Korean Peninsular (국내의 지역별 우박 발생 빈도 분석)

  • Lee, Young-Kyu;Lee, Jae-Soo;Lee, Sung-Su;Kim, Hak-Sun
    • 한국방재학회:학술대회논문집
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    • 2007.02a
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    • pp.81-84
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    • 2007
  • Data for occurrence of hail over Korean Peninsula for the period 1961-2005 are obtained from the Korea Meteorological Administration (KMA). According to the average occurrences during each season in Korea Peninsular, hail days are almost distributed uniformly in the spring, fall and winter, except the summer and have averages of 5 days for each season. Analysis of regional occurrence of hail shows that inland of Korea Peninsular is vulnerable to hail in the spring and summer and the islands of Ullung, Baegryeong and Cheju and the coastal regions vulnerable in the fall and winter. It can be postulated that these seasonal patterns of hail is affected by the Monsoon effect.

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