• 제목/요약/키워드: Summer period

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Changes of plasma melatonin level and testis weight in the seasonal light-period

  • Han, Sang-Zin
    • 한국환경독성학회:학술대회논문집
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    • 한국환경독성학회 2003년도 춘계학술대회
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    • pp.160-160
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    • 2003
  • Plasma melatonin in the seasonal light-period is circadian rhythmically secreted. Maximal secretion showed at 14 o'clock in summer- and winter-like period, but minimal secretion showed at 5 o'clock in summer-like period and at 8 in winter-like period. These times of minimal secretions were at the beginning of light period. Plasma melatonin in the light period is secreted 62.5% more than in the dark period in summer-like period and 45.9% more in winter-like period. Total plasma melatonin in winter-like period is secreted 56.5% more than in summer-like period. The weights of testis(-20.8%) and body(-7.1%) were reduced in the winter-like period. By the increase of plasma melatonin in mice, body- and testis-weights are decreased, on the contrary by the decrease of plasma melatonin in mice, body and testis weights are increased. In view of the results so far achieved melatonin changes on the body weight and reproductive organ in mice. It is presumed that melatonin effects on the metabolism and sex hormone.

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인위적인 계절적 광주기에서 쥐에 나타나는 멜라토닌 분비양상과 정소크기변화 조사 (Changes of Plasma Melatonin Level and Testis Weight in Mice in the Seasonal Light-period)

  • 한상진
    • Environmental Analysis Health and Toxicology
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    • 제18권1호
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    • pp.57-61
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    • 2003
  • Plasma melatonin in the seasonal light-period is circadian rhythmically secreted. Maximal secretion showed at 14 o'clock in summer- and winter-like period, but minimal secretion showed at 5 o'clock in summer-like period and at 8 in winter-like period. These times of minimal secretions were at the beginning of light period. Plasma melatonin in the light period is secreted 62.5% more than in the dark period in summer- like period and 45.9% more in winter- like period. Total plasma melatonin in winter-like period is secreted 56.5% more than in summer-like period. The weights of testis (-20.8%) and body (-7.1%) were reduced in the winter-like period. By the increase of plasma melatonin in mice, body - and testis -weights are decreased, on the contrary by the decrease of plasma melatonin in mice, body and testis weights are increased. In view of the results so far achieved melatonin changes on the body weight and reproductive organ in mice. It is presumed that melatonin effects on the metabolism and sex hormone.

하계 특수경부하기간의 단기 전력수요예측 (Short-Term Load Forecast for Summer Special Light-Load Period)

  • 박정도;송경빈
    • 전기학회논문지
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    • 제62권4호
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    • pp.482-488
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    • 2013
  • Load forecasting is essential to the economical and the stable power system operations. In general, the forecasting days can be classified into weekdays, weekends, special days and special light-load periods in short-term load forecast. Special light-load periods are the consecutive holidays such as Lunar New Years holidays, Korean Thanksgiving holidays and summer special light-load period. For the weekdays and the weekends forecast, the conventional methods based on the statistics are mainly used and show excellent results for the most part. The forecast algorithms for special days yield good results also but its forecast error is relatively high than the results of the weekdays and the weekends forecast methods. For summer special light-load period, none of the previous studies have been performed ever before so if the conventional methods are applied to this period, forecasting errors of the conventional methods are considerably high. Therefore, short-term load forecast for summer special light-load period have mainly relied on the experience of power system operation experts. In this study, the trends of load profiles during summer special light-load period are classified into three patterns and new forecast algorithms for each pattern are suggested. The proposed method was tested with the last ten years' summer special light-load periods. The simulation results show the excellent average forecast error near 2%.

팔당댐 담수수역 식물플랑크톤의 수직분포 (Vertical Distribution of Phytoplankton in the Paldang Dam Reservior)

  • 이경
    • Journal of Plant Biology
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    • 제29권2호
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    • pp.117-127
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    • 1986
  • Phytoplankton community was investigated at the Paldang Dam Reservoir in the Mid-Han River by it's depth, in spring and summer known as the period of phytoplankton's blooming. It was only in summer that phytoplankton bloomed at the investigated area. 128 kinds of phytoplankton were identified and of them, diatoms were abundunt in spring but cyanophyta and chlorophyta were in summer. Because some species with high pollution index were observed in summer, it could be proved that the investigated area was polluted especially in summer. In spring shown the circulation period by vertical distribution pattern of chlorophyll-a and isothermal distribution pattern of water temperature, maximum value of phytoplankton standing crops appeared at the upper layer, except for surface layer. In summer shown the circulation period after the stagnation period by vertical distribution pattern of chlorophyll-a and immediate destruction after stratification of water temperature, maximum value of phytoplankton standing crops appeared at the lower layer. the layer at which the maximum value of chlorophyll-a appeared also accorded with that of phytoplankton standing crops. So, it could be approved that there existed a close relationship among phytoplankton standing crops, chlorophyll-a, and water temperature.

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개화기에 저온 피해를 받은 '후지'/M.9 사과나무의 하계전정 시기가 신초생장 및 과실품질에 미치는 영향 (Influence of Summer Pruning Time on Shoot Growth and Fruit Quality of 'Fuji'/M.9 Apple Tree Damaged by the Low Air Temperature at Flowering Period)

  • 권헌중;사공동훈
    • 한국환경농학회지
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    • 제41권4호
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    • pp.328-334
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    • 2022
  • BACKGROUND: The low temperature at flowering period break the balance between vegetative and reproductive growth of apple tree. Summer pruning has been used to control vegetative growth. So, this study was conducted to investigate the effect of summer pruning time on shoot growth and fruit quality of 'Fuji'/M.9 apple trees damaged by the low temperature at flowering period. METHODS AND RESULTS: The following treatments were applied to tree : a) control (no summer pruning), b) pruned 26 June, c) pruned 30 July, d) pruned 28 August, and e) pruned 26 September. The summer pruning significantly increased light penetration and fruit red color by reducing the total shoot growth compared with control. And the summer pruning control the outbreak of apple valsa canker. But the summer pruning at the end of June increased regrowth of shoot and pruning weight compared with the summer pruning at the end of August. The summer pruning at 30 July had the highest fruit weight, but return bloom was the highest in the summer pruning at 28 August. CONCLUSION(S): These results indicated the optimum summer pruning time of 'Fuji'/M.9 apple trees damaged by the low temperature at flowering period were the end of August.

한국의 하계 강수량의 순변화 유형과 강수지역 (The Variation Patterns over a Period of 10 Days and Precipitation Regions of Summer Precipitation in Korea)

  • 박현욱;류찬수
    • 한국지구과학회지
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    • 제26권5호
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    • pp.417-428
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    • 2005
  • 아시아의 동안에 위치한 한반도는 수리적, 지리적 요인에 의해 지역에 따라 강수현상 및 탁월 일기의 다소와 그 계절변화가 크다. 이러한 탁월한 날씨의 특징은 한국의 하계의 강수출현율과 그 순변화에 잘 반영되고 있다. 본 논문은 한국의 78개 관측지점의 하계강수량$(1991\~2003)$의 순별 평균값에 대해 주성분분석법을 응용하여 하계강수량의 순변화형을 추출하고, 그의 공간스케일과 강수량의 다소에 따라 강수지역구분을 한 것이다. 주성분 분석에 의해 추출된 주성분 벡터와 진폭계수(Rs)에 따라 하계 강수량 순변화의 전형적인 특징은 두 개의 순변화형으로 표현되며 그 누적기여율은 $64.3\%$이다. 또한 한국의 하계 강수량의 순변화형은 $A\~K$형까지 9개가 추출되었고, 강수지역은 17개형으로 분류되었다.

하계강수량과 그 순변화형에 의한 호남지방의 지역 구분 (Regional Divisions of Honam Region by Summer Precipitation and Variation Patterns over a Period of 10 days)

  • 박현욱
    • 한국지역지리학회지
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    • 제11권1호
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    • pp.101-113
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    • 2005
  • 한반도의 남서부에 위치한 호남지방은 수리적, 지리적 요인에 의해 지역에 따라 하계의 강수현상 및 탁월일기의 다소와 그 계절변화가 크다. 본 논문은 AWS 63개 지점을 포함한 호남의 79개 기상관측지점의 하계강수량(1994$\sim$2003)과 그 순변화형(강수특성 표현의 중요한 한 요소임)에 대해 순별 강수량의 다소와 순장수량의 주성분벡터와 진폭계수(Rs)를 이용하여, 호남 각 지역에서의 하계강수량 순변화형을 수량적으로 추출하고, 그 공간스케일의 변동을 규명해, 그에 따른 호남지방의 강수지역 구분을 시도한 것이다. 그 결과 호남지방의 하계강수량 순변화의 전형적 특징은 상위 4개의 순변화형으로 표현되며 그 누적기여율은 78.0%이다. 또한 호남지방의 하계강수량의 순변화형은 A-K형까지 11개가 추출되었고, 강수지역은 18개형 지역으로 구분되었다.

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삼복첩의 치료 효과와 만족도에 대한 연구 (A Study on Effect and Satisfaction of Acupoint Sticking in Hottest Period of Summer)

  • 송지현;이진화;김윤희
    • 대한한방소아과학회지
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    • 제32권1호
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    • pp.1-10
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    • 2018
  • Objectives The purpose of this study is to understand effect on respiratory disease and satisfaction of parents about acupoint sticking in hottest period of summer. Methods A survey was conducted to the parents of their children who took acupoint sticking in Dog-days for two years in a row. 17 children (10 boys, 7 girls, 4.0-12.11 years) were attached Socheongo to BL-13, BL-15, BL-17 for 3 hours. In terms of the effectiveness of the therapy, the treatment only considered as effective when there is any improvement in respiratory symptoms. Results 11 children (64.7%) from the study group have shown positive effect. There were significant improvements in frequency of having a cold or duration of a cold; duration of rhinitis; frequency of having empyema or its duration; frequency of having bronchitis; frequency of having pneumonia; frequency of having otitis media. Respiratory health VAS (Visual Analog Scale) had significant increase from 5 to 6.71 (p<0.05). 7 parents (41.2%) were satisfied with acupoint in hottest period of summer and 16 parents (94.1%) wanted to have their children get treated again in next year. From the survey, inconveniences of acupuncture were weak attachment of the acupoint (23.5%), long attaching time (11.8%), pressure about number of treatments (5.9%), worry about side effects (5.9%). Side effects have been reported; 2 pruritus (11.8%), 1 pruritus and erythema (5.9%). Conclusions Acupoint sticking in hottest period of summer improves lung symptoms in children older than three years old. However, the ways to reduce the side effects and inconveniences are needed.

최근 한반도 여름철 강수특성의 변화 (Recent Changes in Summer Precipitation Characteristics over South Korea)

  • 박창용;문자연;차은정;윤원태;최영은
    • 대한지리학회지
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    • 제43권3호
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    • pp.324-336
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    • 2008
  • 본 연구에서는 최근의 한반도 여름철 강수특성을 파악하기 위해 장기간($1958{\sim}2007$년) 관측을 수행하고 있는 기상관측소를 대상으로 강수량의 변화 경향을 시 공간적으로 분석하였다. 여름철($6{\sim}9$월) 강수량의 연변화를 분석하고 여름철을 장마와 장마 후 강수기간으로 구분하여 그 특징을 살펴보았다. 장마기간에는 남서풍과 준정체전선의 영향으로 산악지역의 풍상측에서 최대 강수량이 발생하였으며 장마 후 강수기간에는 한반도 주변의 서쪽 및 남동쪽에서 유입되는 하층순환장과 함께 태풍, 대류불안정, 저기압성 강수에 의해 주로 남해안과 영동 산간 및 해안지방에서 최대 강수량이 나타났다. 여름철($6{\sim}9$월) 강수량의 시계열 변화에서는 모든 지점에서 강수량이 증가하는 경향을 보여주었으며 이 중에서도 최근 10년이 가장 큰 증가 경향을 보였다. 일 강수량을 10년 단위로 평균하여 분석한 결과, 모든 지점에서 최근 10년에 장마 및 장마 후 강수기간의 강수량이 가장 크게 증가하는 것으로 나타났다. 지점별로 증가 경향은 차이를 보여주었는데, 강릉은 장마 후 강수기간의 강수량이 장마기간보다 더 많았으며 최근 들어 장마 후 강수기간의 강수량이 가장 크게 증가하였다. 서울과 부산의 경우는 최근 10년 동안 여름철 강수량의 두 개 최대값 사이의 강수량이 크게 증가하는 경향을 보여주었다.

1993/1994년을 기점으로 나타난 한반도 여름철 강수량 변동의 종관기후학적 원인 (Change of Synoptic Climatology Associated with the Variation of Summer Rainfall Amount over the Korean Peninsula Around 1993/1994)

  • 김재훈;이태영
    • 대기
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    • 제22권4호
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    • pp.401-413
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    • 2012
  • In this study, an investigation has been carried out to understand 1) temporal variation of rainfall amount in summer over south Korea during the 30-year period of 1979-2008 and 2) the relationship between the variation of rainfall amount and the change of large-scale monsoon circulation around 1993/1994 over East Asia. The analysis of rainfall amount is carried out separately for whole summer (June-August), climatological Changma period of 23 June-23 July, and August to consider variations within summer. To relate the variation of rainfall amount with the change of large-scale circulation, we have considered two 15-year periods of 1979-1993 and 1994-2008. This study has used observations at 58 stations in South Korea and NCEP-NCAR $2.5^{\circ}{\times}2.5^{\circ}$ reanalysis data. The major change in synoptic environment for the Changma period is characterized by the intensified anticyclone over Mongolia during 1994-2008, which results in a weak meridional oscillation of Changma front. As a result, rainfall amount for the Changma period and the frequency of extreme events have significantly increased after 1993/1994. A major change of synoptic environment for August is the significant westward extension of the western Pacific subtropical high, which allows not only more moisture transports but also stronger cyclonic circulation over the Korean peninsula. Rainfall amount for August and frequency of extreme events have also increased after 1993/1994. However, variability of rainfall amount is larger for August than that for the Changma period, with some years showing very dry August (monthly rainfall amount less than 150 mm).