• Title/Summary/Keyword: Low temperature tolerance range

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The Adaptability of Korean Farmers to Environment by the Seasonal Fluctuation of Energy Expenditure, Cold and Heat Tolerance (에너지대사의 계절변동과 내한내열성으로 본 한국농업인의 환경적응 능력)

  • Choi Jeong-Wha;Hwang Kyoung-Sook
    • The Korean Journal of Community Living Science
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    • v.17 no.2
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    • pp.49-60
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    • 2006
  • It was measured the energy expenditure in each season, the cold tolerance in winter and the heat tolerance in summer. Farmers' adaptability to the change of environment was compared with those of city-dwellers such as indoor workers and street cleaners to determine the effect of living environment, especially living temperature, on the health of human body. It turned out that farmers had experienced wide range of temperature that was higher in summer and lower in winter than indoor workers. Farmers and street cleaners showed seasonal adaptation in energy expenditure, which was high in winter and low in summer. However, indoor workers did not show seasonal changes. Energy expenditure had an inverse correlation with the temperature in work place where subjects spend the longer time in a day except in female indoor workers in Seoul. And It was proved that farmers and street cleaners had stronger cold tolerance and heat tolerance than indoor workers.

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Fabrication of Micromachined Ceramic Thin-Film Pressure Sensors for High Overpressure Tolerance

  • Chung, Gwiy-Sang
    • Proceedings of the Korean Society Of Semiconductor Equipment Technology
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    • 2002.11a
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    • pp.59-63
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    • 2002
  • This paper reports on the fabrication process and characteristics of a ceramic thin-film pressure sensor based on Ta-N strain-gauges for harsh environment applications. The Ta-N thin-film strain-gauges are sputter-deposited on a thermally oxidized micromachined Si diaphragms with buried cavities for overpressure tolerance. The proposed device takes advantage of the good mechanical properties of single-crystalline Si as a diaphragm fabricated by SDB and electrochemical etch-stop technology, and in order to extend the temperature range, it has relatively higher resistance, stability and gauge factor of Ta-N thin-films more than other gauges. The fabricated pressure sensor presents a low temperature coefficient of resistance, high-sensitivity, low non-linearity and excellent temperature stability. The sensitivity is 1.21 ~ 1.097 mV/V.kgf/$\textrm{cm}^2$ in temperature ranges of 25~ $200^{\circ}C$ and a maximum non-linearity is 0.43 %FS.

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Growth and Environmental Tolerances (Water Temperature and Low Salinity) of Hybrid Female Red Sea Bream Pagrus major × Male Black Sea Bream Acanthopagrus schregeli (교잡어, 참돔 (Pagrus major, ♀) × 감성동 (Acanthopagrus schregeli, ♂)의 성장 및 수온변화와 저염분 환경에서의 내성)

  • Kim, Yang-Su;Ji, Seung-Cheol;Biswas, Biswajit Kumar;Biswas, Amal;Jeong, Gwan-Sik;Murata, Osamu;Takii, Kenji
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.44 no.3
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    • pp.276-283
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    • 2011
  • The growth and tolerance for water temperature and salinity were compared among red sea bream Pagrus major (RSB) black sea bream Acanthopagrus schregeli (BSB) and their hybrid ($F_1$), female RSB ${\times}$ male BSB. The growth of the $F_1$ fish did not differ until 27 days after hatching (dAH), after which the most rapid growth was observed until approximately 300 dAH, followed by RSB and BSB. However, the RSB had out grown the $F_1$ fish by approximately 303 dAH. By 480 dAH, the RSB were largest, followed by the $F_1$ and BSB groups. The tolerances for high and low water temperature were significantly different for each species and growth stage. The largest tolerance spectrum was observed in the BSB group, and the tolerance spectrums gradually decreased with increasing final body weight. During the salinity tolerance trials, all of the species started to die following transfer into freshwater (0 psu). BSB showed the highest survival rate when kept in fresh water for an average of 29.9 hours, while the $F_1$ fish were more tolerant than the RSB fish. The fish were increasingly tolerant to fresh water and changes in water temperature as they grew, while the size of the temperature spectrum remained unchanged but shifted to a lower temperature range with growth. Our results demonstrate that $F_1$ performed well in terms of growth compared to parental fish, with higher temperature and salinity tolerances than RSB, and is thus suggested to be a suitable aquaculture species for Korea and northeast China.

The Fabrication of a Micromachined Ceramic Thin-Film Pressure Sensor with High Overpressure Tolerance (과부하 방지용 마이크로머시닝 세라믹 박막형 압력센서의 제작)

  • Lim, Byoung-Kwon;Choi, Sung-Kyu;Lee, Jong-Chun;Chung, Gwiy-Sang
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2002.07b
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    • pp.731-734
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    • 2002
  • This paper describes on the fabrication and characteristics of a ceramic thin-film pressure sensor based on Ta-N strain gauges for harsh environment applications. The Ta-N thin-film strain gauges are sputter deposited onto a micromachined Si diaphragms with buried cavity for overpressure protectors. The proposed device takes advantages of the good mechanical properties of single crystalline Si as diaphragms fabricated by SDB and electrochemical etch-stop technology, and in order to extend the operating temperature range, it incorporates relatively the high resistance, stability and gauge factor of Ta-N thin-films. The fabricated pressure sensor presents a low temperature coefficient of resistance, high sensitivity, low non-linearity and excellent temperature stability. The sensitivity is $1.097{\sim}1.21mV/V{\cdot}kgf/cm^2$ in the temperature range of $25{\sim}200^{\circ}C$ and the maximum non-linearity is 0.43 %FS.

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Fabrication of a Micromachined Metal Thin-film Type Pressure Sensor for High Overpressure Tolerance and Its Characteristics (과부하 방지용 마이크로머시닝 금속 박막형 압력센서의 제작과 그 특성)

  • Kim, Jae-Min;Lim, Byoung-Kwon;Chung, Gwiy-Sang
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2002.05a
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    • pp.192-196
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    • 2002
  • This paper describes on the fabrication and characteristics of a metal thin-film pressure sensor based on Cr strain-gauges for harsh environment applications. The Cr thin-film strain-gauges are sputter-deposited onto a micromachined Si diaphragms with buried cavity for overpressure protectors. The proposed device takes advantages of the good mechanical properties of single-crystalline Si as diaphragms fabricated by SDB and electrochemical etch-stop technology, and in order to extend the operating temperature range, it incorporates relatively the high resistance, stability and gauge factor of Cr thin-films. The fabricated pressure sensor presents a low temperature coefficient of resistance, high-sensitivity, low non-linearity and excellent temperature stability. The sensitivity is 1.097~1.21 $mV/V{\cdot}kgf/cm^2$ in the temperature range of $25{\sim}200^{\circ}C$ and the maximum non-linearity is 0.43 %FS.

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Axenic purification and cultivation of an Arctic cyanobacterium, Nodularia spumigena KNUA005, with cold tolerance potential for sustainable production of algae-based biofuel

  • Hong, Ji-Won;Choi, Han-Gu;Kang, Sung-Ho;Yoon, Ho-Sung
    • ALGAE
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    • v.25 no.2
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    • pp.99-104
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    • 2010
  • A psychrotolerant cyanobacterium, Nodularia spumigena KNUA005, was isolated from a cyanobacterial bloom sample collected near Dasan Station in Ny-${\AA}lesund$, Svalbard Islands during the Arctic summer season. To generate an axenic culture, the isolate was subjected to three purification steps: centrifugation, antibiotic treatment and streaking. The broad antibacterial spectrum of imipenem killed a wide range of heterotrophic bacteria, while the cyanobacterium was capable of enduring both antibiotics, the remaining contaminants that survived after treatment with imipenem were eliminated by the application of an aminoglycoside antibiotic, kanamycin. Physical separation by centrifugation and streaking techniques also aided axenic culture production. According to the cold-tolerance test, this mat-forming cyanobacterium was able to proliferate at low temperatures ranging between 15 and $20^{\circ}C$ which indicates the presence of cold-tolerance related genes in N. spumigena KNUA005. This suggests the possibility of incorporating cold-resistance genes into indigenous cyanobacterial strains for the consistent production of algae-based biofuel during the low-temperature seasons. Therefore, it is needed to determine the cold-tolerance mechanisms in the Arctic cyanobacterium in the next research stage.

Critical Low Temperature and Response of Behavioral Tolerance in Red Seabream Pagrus major fingerlings Exposed to Cold Shock (저온 충격에 노출된 참돔 Pagrus major 치어의 임계 저 수온 및 행동 내성 반응)

  • Yoon, Sung Jin
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.22 no.1
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    • pp.575-584
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    • 2021
  • The critical low temperature and response of the behavioral tolerance of red sea bream Pagrus major fingerlings were determined using the continuous behavior monitoring system (CBMS). The behavior of the experimental organisms was observed by decreasing the water temperature by 2.0℃ and 4.0℃ every 12 hours and 24 hours in the range of 8.0-20.0℃. An unstable behavior pattern was observed in red seabream fingerlings exposed to water temperatures below 12.0℃, in which the swimming activity decreased and repeatedly stopped, regardless of the exposure time and water temperature fluctuation. The swimming ability of the organisms exposed to 8.0-10.0℃ decreased sharply, and the behavior of staying at the bottom of the test tank was observed. Only 50 % of the organisms survived due to the low-temperature stress, and all individuals died within six hours after the cold shock. In addition, the behavior index (BI) decreased rapidly, and the amplitude change of the coefficient of variation (CV) was found to have a greater variation than the other water temperatures (p<0.05). Low-temperature stress of red sea bream is promoted at 12.0℃, and it is interpreted as the tolerance limit, which can induce a sublethal response of the organisms exposed to cold shock of 8.0-10.0℃.

Cold Tolerance Assessment of Ever Ground-cover Plants for Extensive Green Roof System (저관리형 옥상녹화를 위한 상록 지피식물의 내한성 평가)

  • Zhao, Hong-Xia;Li, Hong;Son, Hee-Jun;Kang, Tai-Ho
    • Journal of the Korean Institute of Landscape Architecture
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    • v.40 no.4
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    • pp.127-134
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    • 2012
  • This study was carried out to suggest an experimental base in selecting the cold tolerance of plants. The cold tolerance of the plants were subject to laboratory low temperature treatments and cold processing time were evaluated using both electrolyte leakage and regrowth test. The Logistic model of nonlinear regression analysis was used to evaluate the lethal temperatures that were predicted with the range of $-16.1{\sim}-24.4^{\circ}C$. The order of low-temperature resistance was Sedum reflexum > S. spurium > Ophiopogon japonicus > S. album > S. takevimense > Dianthus chinensis. At the lowest temperature of $13.4^{\circ}C$ the electrolyte leakage value of the plants were lower than 50% demonstrating that they could be applied stably to the roof installed in Korea during the winter with the lowest temperature of $-13.5^{\circ}C$.

Cultural characterization of probiotic Lactobacillus sakei BK19

  • Yang , Byung Gyoo;Song , Choon Bok;Yeo , In Kyu;Lee , Kyoung Jun;Park , Geun Tae;Lee, Sang Hyeon;Son, Hong Joo;Heo, Moon Soo
    • Journal of fish pathology
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    • v.16 no.2
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    • pp.119-123
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    • 2003
  • We have selected an valuable pmbiotic strain; Lactobacillus sakei BK19 which has wide antagonic spectrum against fish pathogens . Present study investigated cultural characterization of L. sakei BK19 including pH tolerance , susceptibility of antibacterial agents and growth pattern with different environment such as nutritions, temperature and salinity. L. sakei BK19 showed Significantly higher resistance at low pH(around pH 4) environment and relative high antibiotic tolerance . In the study of optimal culture condition, maltose and saccharose provided the optimal nutritional culture condition while lactose and mannitol were unable to supply its carbon source for the fermentation of L. sakei BK19. Moreover. L. sakei BK19 showed good growth at the temperature range of 15 to $45^{o}C$ und the NaCl concentration of 0 to 7%. Hence, this particular probiotic strain may be benificial both in seawater and fresh weter conditions.

Effect of Soil Moisture and Temperature on the Survival of the Root-Knot Nematode (Meloidogyne incognita, Meloidogyne., arenaria and Meloidogyne hapla.) (토양수분 및 온도가 뿌리혹선충 (Meloidogyne incognita, M. arenaria, M. hapla) 의 생존에 미치는 영향)

  • 박수준
    • Journal of the Korean Society of Tobacco Science
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    • v.1 no.1
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    • pp.39-45
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    • 1979
  • Egg masses of the root- knot nematodes ( Meloidogyne incognita, M. arenaria and M. haply) were exposed to two different regimes of soil moisture (459 and 2459) and temperature ( -2$^{\circ}C$ and 33$^{\circ}C$), quite extreme condition in their natural environment, and their survival rate was compared. Three species did not show any difference in the rate when exposed to either soil moisture for 25 days, with the rate in the range of 8.6% to 10.4%. In response to temperature treatment, however, they differed : the best survival rate was obtained from M. incognita at high temperature ( 33"C) and from M, hapla at low temperature (-2$^{\circ}C$) plot. The third species (M. arenaria) was intermediate in both temperature regimes.imes.

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