• 한국초지조사료학회지
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• 제13권2호
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• pp.112-121
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• 1993

To study management practices suitable for the least production loss of temperate pasture under summer stress, two different cutting dates (late June and mid July) under summer stress and five different nitrogen treatment application levels (0, 100. 200, 300 and 400 kg/ha) were tried during the trial period between Oct. of 1986 and Oct. of 1989. The late June cutting showed a statistically significant increase of dry matter yield of pasture in comparison with the mid-July cutting(P<0.05). Nitrogen application also gave significant increase in dry matter yield. Botanical composition at the 4th cuttings in 1988 and 1989 was dominated by weeds to the level of 50%, Application ofnitrogen at 200 kgs per ha was found to be the best with production of grasses at 70%, legumes at 10 % and weeds at 20% in botanical composition comparison of pastures at the 4th cutting time the last year, showing a great decrease of weeds. K contents of pasture in June cuttings showed to be more than them in July cutting, and N and Na contents increased with increases of the nitrogen application level. It was concluded that treatment with June cutting and nitrogen application of 200 kg per ha was a way to keep temperate pasture from summer stress in the Cheju area.

• 한국초지조사료학회지
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• 제9권2호
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• pp.96-102
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• 1989

This field experiment was conducted to determine the effect of grazing and cutting management on the forage production and botanical composition at different legumes sown swards of the experimental field of Livestock Experiment Station. in Suweon, from Aug. 1985 to Oct. 1988. The results obtained are as follows: 1. Dry matter yield of cutting management (1213.0 kg/lOa) was higher by 19% than that of grazing management (1016.8 kg/lOa). Yield of pasture mixtures including alfalfa both cutting and grazing were higher than those including ladino clover and red clover. Yield under grazing was inferior to cutting in the first year but superior in the second year. 2. Seasonal dry matter production under grazing showed 5 1% in spring, 33% in summer and 16% in autumn, but under cutting showed 46% in spring, 42% in summer and 12% in autumn. 3. Daily dry matter production per 10a under grazing is decreased 5.9 kg in spring, 5.5 kg in summer and 3.7 kg in autumn. But under cutting is decreased 8.7 kg in summer, 6.6 kg in spring and 3.4 kg in autumn. 4. Botanical compositions of mixtures swards involving ladino clover and red clover were not influenced by method of defoliation. But mixtures swards including alfalfa were highly influenced by method of defoliation. Alfalfa ratio at the time of final utilization under grazing was about 30%, but under cutting was about 70-80%.

• Journal of Astronomy and Space Sciences
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• 제35권2호
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• pp.83-92
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• 2018

The summer polar lower thermosphere (90-100 km) has an interesting connection to meteors, adjacent to the mesopause region attaining the lowest temperature in summer. Meteors supply condensation nuclei for charged ice particles causing polar mesospheric summer echoes (PMSE). We report the observation of meteor trail with nearly horizontal transit at high speed (20-50 km/s), and at last with re-enhanced echo power followed by diffusive echoes. Changes in phase difference between radar receivers aligned in meridional and zonal directions are used to determine variations in horizontal displacements and speeds with respect to time by taking advantage of radar interferometric analysis. The actual transit of echo target is observed along the straight pathway vertically and horizontally extended as much as a distance of at least 24 km and at most 29 km. The meteor trail initially has a signature similar to 'head echoes', with travel speeds from 20 - 50 km/s. It subsequently transforms into a different type of echo target including specular echo and then finally the power reenhanced. The reenhancement of echo power is followed by fume-like diffusive echoes, indicating sudden release of plasma as like explosive process probably involved. We discuss a possible role of meteor-triggered secondary plasma trail, such as fireball embedded with electrical discharge that continuously varies the power and transit speed.

• 대기
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• 제18권4호
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• pp.249-266
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• 2008

The tendencies for teleconnection with a time lag and other characteristics of Korean summer droughts have been investigated and some clues to predict the drought occurrences several months before have been found. First, the May and June droughts in Korea are simultaneous with those over the northwestern part of Korea owing to the relation with the baroclinic wave. However, the July and August droughts occur over the mid-latitudes or southern part of Korea owing to the relation with the Changma front. Second, several months before the MJJA droughts in Korea, it is found that the effective drought index (EDI) over particular areas (hereafter, referred to as the omen areas) is large. Thailand, Carolina Island, Mongolia, and Central Bengal Bay were selected as the omen areas. Third, when the monthly minimum EDI (MME) of the omen area in winter is more than 0.7, it signifies that the precipitation is above normal, Korea has almost always experienced a summer drought. However, the droughts occurring with this type of relationship only represent half of the MJJA droughts in Korea. Fourth, the relationships between the Korean drought and the precipitation over omen areas in low latitudes are not valid over all the eight precipitation areas in Korea, but only over Areas I, II, and III, where heavy rains occur during spring and summer.

• 한국실내디자인학회:학술대회논문집
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• 한국실내디자인학회 2001년도 춘계학술발표대회 논문집
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• pp.117-120
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• 2001

This study is a preliminary research to develop design principles for environmentally friendly housing. The purposes of study are to investigate the literatures related passive design for summer and theory of ventilation, to analyze the indoor airflow patterns in traditional Korean house during summer, and to propose the design factors for effective passive cooling system. The analysis for airflow patterns was focused on the ‘An bang’and the ‘Dae Chung’in the ‘An Chae’of a traditional house located in Seoul. Field measurements of air temperature and air velocity were carried out at 30 different measuring points with 8 different window-opening conditions. The measurements were taken on the hottest summer days in August 2000. It is concluded that from an environmentally friendly standpoint design factors to control indoor thermal environment by a passive cooling system during the summer are as follows; ceiling structure has thermal performance like a time-lag effect, optimum height and length of eaves which can prevent sunlight and divert airflow toward the sitting level, building arrangement acceptable the prevailing wind, strategic window arrangement which makes cross ventilation possible (especially north-south) at the sitting level, window opening condition which is possible to intersect two cross-ventilation stream at the main living areas, northward windows remaining in shade to create the air pressure difference, and planning building shape like a bracket that has optimum width and depth.

• Journal of the Korean Wood Science and Technology
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• 제50권3호
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• pp.167-178
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• 2022

To investigate the influence of manufacturing environment on bonding performance of mixed cross laminated wood (CLT) using polyurethane (PUR) adhesive, a boiling water soak delamination test according to the temperature and relative humidity was conducted. The 5-ply mixed CLT consisted of Japanese Larch for external and middle layer and yellow poplar for internal layer. The PUR adhesives with different opening times of 10 and 30 minutes were used. The mixed CLT was manufactured according to pressing times of PUR and manufacturing environments of summer and winter. In case of summer environment, the delamination rate of the mixed CLT with pressing time of 4 hours using a PUR adhesive with open time of 10 minutes met the requirements of KS F 2081. In case of winter environment, the delamination rate of the mixed CLT didn't meet the requirements of KS standard. However, it was possible to confirm the effect of improving the adhesive performance by adjusting the pressing time according to the open time of the adhesive under the manufacturing conditions. The delamination rate of CLT with open time 30 minutes PUR, manufactured by indirect moisture supply methods was 11.2% better than direct moisture supply methods. As a result of delamination test in the same condition of relative humidity and adhesive, it was found that the temperature of manufacturing environment influences the adhesive performance.

• 한국환경과학회지
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• 제29권2호
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• pp.177-189
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• 2020

We analyzed the recent characteristics of Particulate Matter (PM) including PM₁₀ (PM with diameter of less than 10 ㎛) and PM_2.5 (PM with diameter of less than 2.5 ㎛) observed in Busan metropolitan area, and compared them with those measured in Seoul metropolitan area. This analysis includes the monthly, seasonal, and annual variations and differences, in emissions and chemical compositions observed in both Busan and Seoul areas. Synoptic meteorological conditions were investigated at the time when high PM concentrations occurred in each of the two areas. The results showed clearly decreasing trends of annual mean concentrations with strong seasonal variations: lower in summer and higher in winter in both areas. In comparison with Seoul, the seasonal variation in Busan demonstrated relatively lower, but showed greater summer fluctuations than in Seoul metropolitan area. This is implying the importance of secondary generation of PM in summer via active photochemical reaction in Busan area. In high concentration days, Busan's chemical composition of sulfate was higher than that of nitrate in summer, whereas nitrate was higher than sulfate in Seoul. The ratios of NO₃^- to SO₄^2-(N/S ratio) showed lower in Busan approximately by a factor of 1/2(half of N/S ratio) in Busan compared with that in Seoul. Others such as synoptic characteristics and emission differences were also discussed in this study.

• Journal of Preventive Medicine and Public Health
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• 제10권1호
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• pp.25-33
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• 1977

The epidemiological informations on 1,828 cases of acute drug intoxication admmitted to the emergency rooms of 5 general hospitals, 4 in Seoul City and 1 in Incheon City from Jan. 1974 to Dec. 1974, were reviewed for statistical analysis. More detailed information on 796 cases from 3 hospitals were available in terms of the causative agent. The general findings obtained are as follows; 1. The sex ratio of the patient is 1.26 females to 1 male and this figure is almost consistent with the reports of previous authors. 49.7% of total cases were found in the age group of 20-29, which indicate the highest in percent distribution of age. 2. The incidence of acute drug intoxication was different by the season as the highest in summer and the lowest in winter. 3. As the cause of the intoxication, the attempted suicide occupied the single highest one with 91.7%. 4. The kind of causative agents varies with seasons as more economic poisons in the summer time and more drugs in the winter time.

• Animal cells and systems
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• 제2권2호
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• pp.165-176
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• 1998

Seasonal changes in microzooplankton abundance were identified in the mesohaline Chesapeake Bay and several tributaries from July 1992 through December 1995. Ciliates numerically dominated, comprising over 90% of the total microzooplankton density and aloricate ciliates usually outnumbered loricate ciliates. Copepod nauplii accounted for the highest microzooplankton biomass (>75% in dry weight). Rotifers made small contributions to the total microzooplankton density and biomass (<5%). Time series analysis indicated a twelve month cycle in microzooplankton abundance, and mid-summer(August) peaks for copepod nauplii, and a spring through fall peaks (May-October) for ciliates. Rotifers showed two seasonal peaks: one in mid-summer(August) at the river stations and the other in mid-winter(February) at the mesohaline stations. Seasonal peaks of copepod nauplii and rotifers coincided with the mesozooplankton abundance peak. On the other hand, ciliate maximum usually occurred between the phytoplankton and mesozooplankton peaks. This pattern of microzooplankton seasonality suggests the intermediate trophic role of microzooplankton (especially ciliates) between the phytoplankton(especially picophytoplankton) and mesozooplankton in Chesapeake Bay and its tributaries.

• 기독교교육논총
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• 제71권
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• pp.277-303
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• 2022

2020년부터 시작된 코로나19 팬더믹은 한국교회에 많은 변화를 이끌어냈다. 예배시간의 변화와 형태뿐만 아니라 목회의 정의 및 방향과 철학까지 재정립할 수밖에 없는 상황을 만들었다. 코로나19 팬더믹 초기의 한국교회는 이것을 위기로 인식하였으나 점차 이것들을 기회로 여기며 긍정적 결과를 내기 위해 노력하였다. 교육부서 역시 많은 변화를 겪었으며 특별히 여름 사역에 있어서 형태와 장소 및 방법은 다른 어떤 교회 행사나 예배보다 극적인 변화를 겪은 것으로 보이나 이것에 대한 정확한 데이터는 수집되지 않았다. 이에 따라 오륜교회가 다음 세대 사역을 위해 설립한 사단법인 꿈이있는미래 (대표: 김은호 목사)는 코로나19 팬더믹이 시작되던 2020년부터 매년 꿈이있는미래 회원으로 등록된 한국교회 교육부를 대상으로 여름 사역에 대해 설문을 하여 그 결과를 분석하고 한국교회 여름 사역에 대한 정보를 제공하였다. 2021년에 이어 2022년에도 비슷한 설문 조사가 진행되었으며 260여 개의 교회가 응답하였고 그 결과는 다음과 같다. 2022년 한국교회 교육부 여름 사역은 코로나19 팬더믹 이전의 형태로 상당수 회귀 되었다. 상당수 온라인으로 진행되던 2021년과는 달리 81% 이상이 오프라인으로 여름 캠프를 진행했다고 응답하였으며 외부 캠프를 진행하거나 참석하는 것 역시 31%에 달하였다. 역할의 중요도에서 역시 온라인이 주를 이루던 때는 부모와 교사의 역할을 동등하게 보거나 부모를 강조하지만 오프라인 행사가 진행된 이번 여름 조사에서는 90%의 응답자가 담당 사역자나 부서 교사의 역할이 중요하다고 응답하였다. 여름 행사로는 여름성경학교와 수련회가 주를 이루었지만, 전체 응답자의 25%가 국내외 선교와 전도를 했다고 응답할 정도로 다른 사역의 비중 역시 높아졌다. 2021년에 비해 유아부와 유치부, 초등부와 중고등부까지 모든 부서에서 여름 캠프 참여도가 높아졌으며 특별히 유아부와 중고등부에서의 참여도가 크게 높아졌다. 여름 캠프를 준비하면서 가장 주안점을 두는 것은 콘텐츠와 주제라고 응답한 사람이 가장 많았으며 아이들의 접근성을 주요하게 보는 것은 2021년에 비하여 크게 감소하였다. 여름 캠프를 진행하지 못한 응답자들을 대상으로 그 이유에 관한 기술을 종합한 결과 약 40%가 봉사 인원 부족으로 여름 캠프를 진행하지 못했다고 응답하였다. 이는 코로나19를 원인으로 지목한 30%를 웃도는 수치로 한국교회와 교단 차원에서 해결해야 하는 시급한 문제로 볼 수 있다. 이 외에도 본 논문은 각 질문에 대한 세부변화에 대하여서도 언급함으로 2020년부터 2022년에 이르는 여름 캠프의 변화에 대해서 언급하였다.