• 제목/요약/키워드: accumulated temperature

검색결과 554건 처리시간 0.028초

퇴적 목분의 훈소층 전파에 관한 연구 (A Study on the Smoldering Zone Spread of the Heaped Saw-Dust)

  • 정국삼;강민호
    • 한국안전학회지
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    • 제12권3호
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    • pp.90-96
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    • 1997
  • This paper was concerned with temperature aspect in the smoldering time of the accumulated each saw-dust sample of larch, oregon, aromatic trees which was formed with heaped cone-shape. The smoldering time and temperature of each sample was measured under the wind velocity of 0.10~0.15 m/s and circumstance relative humidity of 60%. As a result, the very lowest heat beginning temperature was detected in aromatic. The effective smoldering phenomena in the sample were detected when the larch saw-dust of [-20+40mesh] and the aromatic saw-dust of [-40+50mesh, -50+60mesh]. Finally the larger a particle size of saw-dust was the better a smoldering time was short. Also, it showed more increasing temperature above $70^{\circ}C$in the smoldering reaction.

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Isolation of Cold Acclimation-related Genes in Wheat Chromosome Substitution Line 5D

  • Chun, Jong Un;Jeong, In Ho
    • 한국육종학회지
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    • 제40권3호
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    • pp.234-242
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    • 2008
  • To identify low temperature-induced genes of wheat chromosome substitution line 5D, suppression subtractive hybridization (SSH) was performed with mRNAs from leaf samples that treated with low temperature ($4^{\circ}C$). A cDNA library was constructed using mRNA isolated from wheat chromosome substitution line 5D leaves treated with low temperature ($4^{\circ}C$). The nucleotide and deduced amino acid sequences of the putative gene products were compared. wfr-9 and wfr-32 showed identity over 90% related to vernalization gene. Other two genes, wfr-77 and wfr-83 which is related to freezing-resistant gene have also identity over 90%. This result suggest that those genes may be transcribed into antifreeze proteins which are accumulated within leaf apoplasts, when wheat chromosome substitution line 5D is acclimated during low temperature treatment.

극저온 압연으로 제조된 5052 Al Alloy의 기계적 성질 (Mechanical Properties of Ultrafine Grained 5052 Al Alloy produced by Cryogenic Rolling Process)

  • 이영범;남원종
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2004년도 제5회 압연심포지엄 신 시장 개척을 위한 압연기술
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    • pp.233-239
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    • 2004
  • The effect of annealing temperature on microstructures and mechanical properties of the sheets received $88\%$ reduction at cryogenic temperature was investigated for the annealing temperature of $150\~300^{\circ}C$, in comparison with those at room temperature. The presence of equiaxed grains, whose size is about 200nm in a diameter, was observed in 5052 Al alloy deformed $88\%$ and annealed $200^{\circ}C$ for an hour. When compared with the deformation at room temperature, the deformation at cryogenic temperature showed the higher strengths and equivalent elongation after annealing at the annealing temperature below $200^{\circ}C$. However, for annealing above $250^{\circ}C$ materials deformed at cryogenic temperature showed the lower strength than those deformed at room temperature. This behavior might be attributed to the higher rate of recrystallization and growth in materials deformed at cryogenic temperature during annealing, due to the lager density of dislocations accumulated during the deformation.

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매미나방(Lymantria dispar) 발육에 미치는 온도의 영향 (Effects of Temperature on the Development of Gypsy moth (Lymantria dispar))

  • 조아해;김효정;이진희;김지인
    • 한국응용곤충학회지
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    • 제62권4호
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    • pp.385-388
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    • 2023
  • 매미나방(Lymantria dispar)은 나비목(Lepidoptera) 독나방과(Lymantriidae)에 속하는 해충으로 매미나방은 한국, 일본, 시베리아, 유럽, 북아메리카 등에 분포하며, 주로 배나무, 사과나무, 블루베리 등의 식물을 가해하는 광식성 해충이다. 매미나방은 수목해충으로 관리되어 왔으나 최근 산림 발생지 인접 농경지로 유입 빈도가 높아지면서 방제 대책이 수립되지 않은 농작물에 피해가 심하다. 본 연구는 매미나방(L. dispar)의 방제기술의 일환으로 매미나방 발육에 미치는 온도의 영향을 알아보기 위해 2021년 전라남도 장흥군 황금측백나무에서 채집한 알집을 이용해 18, 21, 24, 27, 30, 33℃ (14L:10D, 상대습도 60±5%) 항온조건에서 온도별, 발육단계별 발육기간을 조사하였다. 매미나방 유충의 발육속도는 온도가 높을수록 빨라졌으나, 매미나방 유충의 생존율이 33℃에서 가장 낮게 나타났다. 따라서 발육적온은 30℃였으며, 30℃에서 총 발육기간은 암컷 43.8일, 수컷 42.5일 소요되었다. 암컷과 수컷 발육영점온도는 각각 13.1℃, 12.5℃, 유효적산온도는 각각 641.1 DD, 657.8 DD였다.

Elevated Temperature Design of KALIMER Reactor Internals Accounting for Creep and Stress-Rupture Effects

  • Koo, Gyeong-Hoi;Bong Yoo
    • Nuclear Engineering and Technology
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    • 제32권6호
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    • pp.566-594
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    • 2000
  • In most LMFBR(Liquid Metal Fast Breed Reactor) design, the operating temperature is very high and the time-dependent creep and stress-rupture effects become so important in reactor structural design. Therefore, unlike with conventional PWR, the normal operating conditions can be basically dominant design loading because the hold time at elevated temperature condition is so long and enough to result in severe total creep ratcheting strains during total service lifetime. In this paper, elevated temperature design of the conceptually designed baffle annulus regions of KALIMER(Korea Advanced Liquid MEtal Reactor) reactor internal strictures is carried out for normal operating conditions which have the operating temperature 53$0^{\circ}C$ and the total service lifetime of 30 years. For the elevated temperature design of reactor internal structures, the ASME Code Case N-201-4 is used. Using this code, the time-dependent stress limits, the accumulated total inelastic strain during service lifetime, and the creep-fatigue damages are evaluated with the calculation results by the elastic analysis under conservative assumptions. The application procedures of elevated temperature design of the reactor internal structures using ASME Code Case N-201-4 with the elastic analysis method are described step by step in detail. This paper will be useful guide for actual application of elevated temperature design of various reactor types accounting for creep and stress-rupture effects.

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배 '신고'의 연차간 과실 생장과 기상 요인과의 상관성 (Relationship between Yearly Fruit Growth and Climatic Factors in 'Niitaka' Pear)

  • 한점화;손인창;최인명;김승희;조정건;윤석규;김호철;김태춘
    • 원예과학기술지
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    • 제31권1호
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    • pp.8-13
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    • 2013
  • 본 연구는 배 '신고'의 과실 생장에 대한 주요 기상 요인의 영향을 알아보고자 수행하였다. 2000년에서 2010년까지 평균 만개일은 4월 19일이었고, 편차는 4.2일이었다. 만개 후 160일째의 평균 과실 횡경은 102.4mm였고 편차는 7.5mm였다. 10년간 기상 요인 중 기온보다 강우량과 일조시수의 변이계수가 컸다. 만개 후 160일째의 과실 횡경은 만개 후 160일 동안의 기상 요인 중에서 누적 일조시수가 상관계수 $r=0.68^*$로 정의 상관을 보였다. 만개일의 조만과 만개 후 160일째의 과실 횡경 간에는 상관성을 나타내지 않았다. 상반된 과실 생장 경향을 보였던 2004년과 2009년은 지속적인 강우 시기의 존재와 그에 따른 일조시수의 차이에 의한 것이었다. 따라서 배 '신고'의 과실 생장은 기온보다는 누적일조시수의 영향을 많이 받는 것으로 판단되었다.

A Yield Estimation Model of Forage Rye Based on Climate Data by Locations in South Korea Using General Linear Model

  • Peng, Jing Lun;Kim, Moon Ju;Kim, Byong Wan;Sung, Kyung Il
    • 한국초지조사료학회지
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    • 제36권3호
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    • pp.205-214
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    • 2016
  • The objective of this study was to construct a forage rye (FR) dry matter yield (DMY) estimation model based on climate data by locations in South Korea. The data set (n = 549) during 29 years were used. Six optimal climatic variables were selected through stepwise multiple regression analysis with DMY as the response variable. Subsequently, via general linear model, the final model including the six climatic variables and cultivated locations as dummy variables was constructed as follows: DMY = 104.166SGD + 1.454AAT + 147.863MTJ + 59.183PAT150 - 4.693SRF + 45.106SRD - 5230.001 + Location, where SGD was spring growing days, AAT was autumnal accumulated temperature, MTJ was mean temperature in January, PAT150 was period to accumulated temperature 150, SRF was spring rainfall, and SRD was spring rainfall days. The model constructed in this research could explain 24.4 % of the variations in DMY of FR. The homoscedasticity and the assumption that the mean of the residuals were equal to zero was satisfied. The goodness-of-fit of the model was proper based on most scatters of the predicted DMY values fell within the 95% confidence interval.

Molecular Cloning of Maltooligosyltrehalose Trehalohydrolase Gene from Nostoc flagelliforme and Trehalose-Related Response to Stresses

  • Wu, Shuangxiu;He, Liang;Shen, Rongrong;Zhang, Xiu;Wang, Quanxi
    • Journal of Microbiology and Biotechnology
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    • 제21권8호
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    • pp.830-837
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    • 2011
  • A genomic DNA fragment encoding a putative maltooligosyltrehalose trehalohydrolase (NfMTH) for trehalose biosynthesis was cloned by the degenerate primer- PCR from cyanobacterium Nostoc flagelliforme. The ORF of NfMTH is 1,848 bp in length and encodes 615 amino acid residues, constituting a 70 kDa protein. The deduced amino acid sequence of NfMTH contains 4 regions highly conserved for MTHs. By expression of NfMTH in E. coli, the function of this protein was demonstrated, where the recombinant protein catalyzed the hydrolysis of maltooligosyl trehalose to trehalose. The expressions of MTH and maltooligosyltrehalose synthase in the filaments of N. flagelliforme were upregulated significantly under dehydration stress, NaCl stress, and high temperature-drought stress. The accumulations of both trehalose and sucrose in the filaments of N. flagelliforme were also improved significantly under the above stresses. Furthermore, trehalose accumulated in smaller quantities than sucrose did when under NaCl stress, but accumulated in higher quantities than sucrose did when under temperature-drought stress, indicating that both trehalose and sucrose were involved in N. flagelliforme adapted to stresses and different strategies conducted in response to various stress conditions.

Transient Analysis of PT-IGBTs at High Temperature

  • Ryu Sehwan;Lee Hokil;Ahn Hyungkeun;Han Deuk-Young
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2001년도 Proceedings ICPE 01 2001 International Conference on Power Electronics
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    • pp.39-43
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    • 2001
  • In this paper, excess minority carrier distribution in drift and buffer layers and accumulated charges for PT IGST have been, for the first time, analytically expressed with different transient times, lifetimes and temperatures. Furthermore those parameters are also expressed with temperature to predict the transient response which are critical to the real operation. Active base region has been chosen to extract the temperature dependency of the device by including the buffer layer which is important but neglected due to the complexity up to now.

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극저온 조건에서의 양생방법 변화에 따른 실구조체 콘크리트의 강도발현 특성 (Strength Development of Mock-up Concrete Structure subjected to Extremely Low Temperature Condition Due to Curing Methods)

  • 정은봉;정상현;안상구;고경택;한민철;한천구
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2012년도 추계 학술논문 발표대회
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    • pp.47-49
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    • 2012
  • Under this study, the characteristics of concrete intensity condition following the curing method under the extremely low temperature environment have been contemplated, and as a result, in the event of insulation + heat cable curing, the intensity and accumulated temperature accomplishment period is required for two times of requiring initial frost damage prevention than the case of heating + heat insulation curing method due to the insufficient calories supplied in general.

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