• Title/Summary/Keyword: 온도 스트레스

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A Thermal Stress Analysis of Disposable Personal Protective Coveralls (일회용 전신 보호복의 온열 스트레스 분석)

  • Soyoung Park;Yejin Lee
    • Journal of the Korean Society of Clothing and Textiles
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    • v.47 no.6
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    • pp.1193-1203
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    • 2023
  • This study aims to provide primary data regarding the thermal stress of disposable personal protective coveralls. Thermal stress and surface temperature measurements were taken among ten men wearing coveralls. The size of the ten men corresponds to a size eight in Size Korea. As a result of thermal stress, sensations of humidity and discomfort were higher when wearing Level C compared to Level D. Level D felt significant thermal stress in their upper body after exercise. However, they did not feel such stress in their lower body. Level C felt thermal stress in their upper and lower body after exercise. In addition, in Level C, the ratings of perceived exertion blood pressure and pulse rate after exercise were higher than those of Level D. Furthermore, the surface temperature of disposable personal protective coveralls among Level C was slightly higher than that of Level D.

Stress Induced Leakage Currents in the Silicon Oxide Insulator with the Nano Structures (나노 구조에서 실리콘 산화 절연막의 스트레스 유기 누설전류)

  • 강창수
    • Journal of the Institute of Electronics Engineers of Korea TE
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    • v.39 no.4
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    • pp.335-340
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    • 2002
  • In this paper, the stress induced leakage currents of thin silicon oxides is investigated in the ULSI implementation with nano structure transistors. The stress and transient currents associated with the on and off time of applied voltage were used to measure the distribution of high voltage stress induced traps in thin silicon oxide films. The stress and transient currents were due to the charging and discharging of traps generated by high stress voltage in the silicon oxides. The transient current was caused by the tunnel charging and discharging of the stress generated traps nearby two interfaces. The stress induced leakage current will affect data retention in electrically erasable programmable read only memories. The oxide current for the thickness dependence of stress current, transient current, and stress induced leakage currents has been measured in oxides with thicknesses between 113.4${\AA}$ and 814${\AA}$, which have the gate area $10^3cm^2$. The stress induced leakage currents will affect data retention and the stress current, transient current is used to estimate to fundamental limitations on oxide thicknesses.

The degradation phenomena in SiGe hetero-junction bipolar transistors induced by bias stress (바이어스 스트레스에 의한 실리콘-게르마늄 이종접합 바이폴라 트랜지스터의 열화 현상)

  • Lee, Seung-Yun;Yu, Byoung-Gon
    • Journal of the Korean Vacuum Society
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    • v.14 no.4
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    • pp.229-237
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    • 2005
  • The degradation phenomena in SiGe hetero-junction bipolar transistors(SiGe HBTs) induced by bias stress are investigated in this review. If SiGe HBTs are stressed over a specific time interval, the device parameters deviate from their nominal values due to the internal changes in the devices. Reverse-bias stress on emitter-base(EB) junctions causes base current increase and current gain decrease because carriers accelerated by the electrical field generate recombination centers. When forward-bias current stress is conducted at an ambient temperature above $140^{\circ}C$ , hot carriers produced by Auger recombination or avalanche multiplication induce current gain fluctuation. Mixed-mode stressing, where high emitter current and high collector-base voltage are simultaneously applied to the device, provokes base current rise as EB reverse-bias stressing does.

노출되어 있는 급수탱크는 우레탄을 발포하거나 지붕을 설치해주면 안정적

  • 이현덕
    • KOREAN POULTRY JOURNAL
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    • v.34 no.7 s.393
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    • pp.75-79
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    • 2002
  • 우리나라의 기후는 분명 변하고 있다. 이미 6월초 부터 실제적으로 혹서기를 맞이한 현재, 우리가 살고있는 이 땅에 봄과 가을은 점점 그 기간이 짧아지고 있다. 불과 몇 년전만 해도 육계 사육에 있어서 가장 혹독한 기간($2\~5$월)을 보내고 나서 적어도 한 파스는 더위 스트레스에 시달리지 않고 사육하여 출하 할 수 있었다. 혹서기에 내 육계농장이 위치한 지역의 온도와 습도, 바람의 방향 등 환경요인을 이해하고 이에 적극적으로 대처해야만 우수한 육계 사육 성적을 확보할 수 있는 바, 본고에서는 우리 육계 사양가들께서 열정과 관심을 갖고 있다면 극복할 수 있는 고온 스트레스 예방 대책에 초점을 맞추고자 한다.

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The Effects of Air Temperature and Age on Soundness of Abies koreana Seeding (대기 온도와 연령이 구상나무 유묘의 건전도에 미치는 영향)

  • Seung-Beom Chae;Han-Na Seo;Hyo-In Lim
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2020.12a
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    • pp.50-50
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    • 2020
  • 기후변화의 영향으로 자생지에서 고사하고 있는 구상나무 유묘의 대기온도와 연령에 따라 건전도를 파악하고자 지리산 구상나무 실생묘를 대상으로 엽록소형광을 측정하였다. 2020년 7, 8, 9월에 걸쳐 월별 1회씩 연생별(1, 2, 3, 5, 6년생) 20개체를 대상으로 13시, 19시에 개체당 3회 반복 측정하였다. 측정 당시 평균대기온도는 24.6, 26.9, 20.6℃이었으며 잎을 20분간 광을 차단 후 Fv/Fm값을 측정하였다. Fo는 식물이 암적응 된 상태에서 포화광을 조사하기 직전의 형광 초기값이며, Fm은 식물이 암적응 된 상태에서 포화광을 통해 유도된 최대 형광수치를 의미한다. Fv는 Fm-Fo이며, 광화학 반응의 최대 양자수율로 식물의 잎이 광합성을 수행할 수 있는 잠재력을 의미하고 식물의 광합성 활성과 건전도에 대한 지표로 사용된다. 일반적으로 건강한 잎의 Fv/Fm값이 0.8을 기준으로 낮은 값은 광계II의 반응 중심이 손상을 잎은 경우이거나 스트레스 환경에 있는 경우이다. 13시 측정 결과 8월 측정값 중 1년생과 3년생이 0.8 이하로 측정되었고 그 외에는 전부 0.8 보다 높게 나타났다. 19시 측정 결과 8월에 1, 2, 3년생이 0.8 이하로 측정되었으며, 9월에는 1년생의 경우를 제외하고 모두 0.8 보다 높게 나타났다. 1, 2, 3년생은 8월의 높은 온도에 영향을 받아 고산지대에 자생하는 구상나무의 특성상 고온에 대한 스트레스를 받은 것으로 판단되며, 연령이 비교적 높은 5, 6년생은 온도변화에 비교적 안정적인 것으로 나타났다. 따라서 엽록소형광 측정의 결과를 근거로 3년생 이하의 개체는 온도변화에 민감하게 반응하는 반면, 5년생 이상의 개체는 비교적 안정적으로 건전도가 유지된 것으로 판단되었다.

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두통과 한방

  • Lee, Jin-Hwa
    • 건강소식
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    • v.24 no.9 s.262
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    • pp.24-25
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    • 2000
  • 두통은 정신적 스트레스, 각종 염증, 외상 등 여러가지 원인에 의해 일어나며 인류의 역사와 함께 해 온 가장 오래된 증상이다. 한방에서는 전신의 균형을 잡아 주고 경락을 소통시키는 치료를 통해 두통 치료에 있어서 상당한 효과를 거두고 있다.

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The Effects of Increased Temperature on Yield Properties, Antioxidant Contents, and Pollen Viability of Adzuki Bean (Vigna angularis L.) Responses in Temperature Gradient Greenhouse and Growth Periods (온도구배온실에서 온도상승이 생육시기별 팥의 수량, 항산화 성분, 화분 임성에 미치는 영향)

  • Eun Ji Suh;Ok Jae Won;Jae-Sung Park;Won Young Han;Jin Hee Seo;Sun Tae Kim;Hye Rang Park
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.68 no.2
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    • pp.47-58
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    • 2023
  • The quality and yield of crops produced using field cultivation are expected to decrease due to the recent global climate change caused by extreme weather. The plant reproductive stage associated with crop yields is a highly vulnerable period to global warming caused by high temperatures. This study analyzed the adzuki bean's yield properties, antioxidant contents, and pollen viability of adzuki bean (Vigna angularis L.) under high-temperature stress and growth periods in a temperature gradient greenhouse that forms 0 to 4℃ above the outside temperatures. As the main variety of red beans cultivated in Korean farms, the "Arari" red bean was grown in the rain shield greenhouse and the temperature gradient greenhouse from 2021 to 2022 in Milyang, Korea. Compared to 2022, it showed a 0 - 1.0℃ lower temperature during the whole growth period in 2021. However, its average temperatures were 0 - 3.7℃ higher in the vegetative stage and 0.4 - 2.4℃ higher in the anthesis stage in 2021. The lowest yield (6.8 ± 0.7 g) was at the highest temperature (T4: low, 23.6℃; average, 28.5℃; high, 35.8℃) during the anthesis stage in 2021. The temperatures of the mature stage were 1.7 - 3.9℃, which were higher in 2022 than in 2021, although the low temperatures of 2022 were lower than in 2021. The yields of the mature stage in 2022 increased more than in 2021 because of the high temperature of the mature stage. The growth and yield were good at 40.5℃ in the vegetative stage. However, growth was poor when the average temperature was 27.0℃ or higher, and yields decreased during the flowering period. Total polyphenol and flavonoid contents were increased, and the pollen viability was 40.75% in the whole growth period at high temperature (T4: low, 22.9℃; average, 28.8℃; high, 36.9℃). These results showed that the antioxidant levels increased when the antioxidant component was affected at higher temperatures than at normal. In contrast, the pollen viability-related yield decreased as the temperature increased. Our results are the basic data for field growers and the breeding of thermos-tolerance in adzuki beans to prepare for the changeable future climate.

EFFECT OF RED GINSENG ON MICE EXPOSED TO VARIOUS STRESSES (홍삼이 스트레스에 노출된 생쥐의 행동에 미치는 영향)

  • Saito Hiroshi;Bao Tiantong
    • Proceedings of the Ginseng society Conference
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    • 1984.09a
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    • pp.97-105
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    • 1984
  • Effect of water extract of red ginseng (Panax ginseng C.A. Meyer) from Nagano prefecture on (1) forced exercise in mice using rope climbing test, (2) extinction of memory in hanging stressed mice and rectal temperature during the exposure to hanging stress, (3) sex and learning behavior of chronic hanging stressed mice, (4) sex cycle in the adult female mice using chronic hanging stress, and (5) motor coordination and one trial passive avoidance response in $40\%$ alcohol administered mice using rotar-rod and step-through tests, were studied. Drugs tested were given orally. (1) When it was given before the forced exercise, it potentiated the performance of the forced exercise. When it was given just after the forced exercise once a day for 2 weeks, it protected the mice against the reduction of the performance on the forced exercise. (2) When it was given just after the stress once a day for 4 days, it delayed the extinction of passive avoidance response in both step through and stepdown tests, and protected the stressed mice against the decrease in rectal temperature slightly. (3) It protected the stressed mice against the decrease of sex behaviour and the increase in the failure of performance of passive avoidance response, and delayed the extinction of passive avoidanc

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