• 화훼연구
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• 제17권2호
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• pp.106-113
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• 2009

자생나리 종자의 발아율은 $20-25^{\circ}C$에서 높았다. 이 온도에서의 솔나리, 땅나리, 털중나리와 하늘나리의 발아율은 거의 100%, 참나리와 중나리는 각각 88.0%와 73.0%였다. 반면 말나리, 섬말나리와 하늘말나리의 발아율은 34.0-54.0%로 낮았다. 발아는 대부분 $15^{\circ}C$에서 지연되어 발아율이 높은 종일수록 발아소요일수가 단축되었다. 발아와 일장과는 대체로 무관하였으나 장일하에서 하늘나리는 촉진된 반면, 말나리와 섬말나리는 억제되었다. 발아속도도 일장효과가 적었으나 중나리는 일장이 길수록 촉진되었고, 섬말나리는 지연되는 경향이었다. PGRs 온탕처리의 효과를 보면, 땅나리, 솔나리, 털중나리, 참나리와 하늘나리의 발아율은 무처리와 차이가 없었다. 그러나 중나리는 BA에 의해 발아율이 향상되었다. 중나리와 참나리는 습윤냉장 기간이 길어짐에 따라 발아율이 향상된 반면, 말나리와 섬말나리는 저하되었다. 발아소요일수는 습윤냉장 기간이 길어질수록 종에 관계없이 단축되었다. 건조저장시의 발아율은 실온보다는 저온저장구에서, 방치구보다는 데시케이터 저장구에서 높아, $4^{\circ}C$ 데시케이터 저장구에서 발아율이 가장 높았다. 하늘나리는 실온에서 장시간 방치시 발아율이 급격히 떨어졌으나, 중나리는 데시케이터 사용만으로도 발아율이 장기간 유지되었다.

• 한국초지조사료학회지
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• 제7권3호
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• pp.146-152
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• 1987

Sorghum cv. Pioneer 93 1, sorghum-sudangrass hybrid cv. Sioux and maize plant cv. Blizzard were assayed for toxic concentrations of nitrate-nitrogen ($NO_3$-N) and their relationship to morphological characteristics and environmental temperature in a field and phytotron trial. In the phytotron, sorghum and maize plants ranging from emergence to heading stage, were grown under different day/night temperatures of 30125, 25/20,28/18 and 1818 degree C. Nitrate-nitrogen in sorghum and maize plants was accumulated mainly in stems. Therefore nitrate concentration in the young plants was increased as development of stalks advanced and was highest at the stage of 3-4 leaves, when the plants had a leaf weight ratio 0.78-0.80 g/g plant weight. However, nitrate concentrations of the plant decreased as morphological development progressed, especially from the stage of growing point differentiation. Correlation coefficients showed a positive correlation of nitrate concentration with leaf weight ratio, leaf area ratio and specific leaf area, while plant height, dry matter percentage and absolute growth rate showed a negative association with TEX>$NO_3$-N ($P{\le}0.1$%). Cyanogenic glycosides, total nitrogen and crude protein were close associated with nitrate accumulation, and positively significant ($P{\le}0.1$%). High temperature over 30/25^{\circ}C.$ for 3 weeks increased N-uptake and dry matter accumulation, but reduced nitrate concentration. Under cold temperature below 18/8^{\circ}C.$ concentration of nitrate-N was increased in spite of its limited nitrogen uptake and plant growth.

• 한국수산과학회지
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• 제43권6호
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• pp.654-658
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• 2010

The purpose of this study is to establish methods for enhancing the survival and growth of cold-water fish and crustacean larvae based on the nutritional components of zoo and phyto live foods. Rotifers, Brachionus rotundiformis, were cultured with a supplement of freshwater condensed Chlorella vulgaris at $28^{\circ}C$ and enriched with Algamac $2000^{(R)}$ at 16, 20 and $26^{\circ}C$, respectively. Isochrysis galbana, Chaetoceros calcitrans and Chlorella ellipsoidea were centrifuged for component analysis after being cultured for approximately one week with conway medium at $20^{\circ}C$. The crude protein and lipid contents of the rotifers were 58.4% and 10.9%, respectively, before enrichment. After enrichment at each temperature, total protein and essential amino acid contents were increased by reducing the enrichment temperature. However, unsaturated fatty acids and multiple fatty acid index (UI) showed their highest values at $20^{\circ}C$. Mono-unsaturated fatty acid content was highest (72.6%) at $16^{\circ}C$. The total protein contents of C. calcitrans and C. ellipsoidea were higher, 33.0% and 35.2%, respectively, than that of I. galbana, 27.8%. Methionin, leusine and histidine, essential amino acids of C. ellipsoidea, had considerably higher values, 50.2, 287.2 and 68.1 mg/g dry matter, respectively, compared to other microalgae. Total lipids, UI, DHA and n-3 PUFA of I. galbana had higher values, 23.6, 272.0, 12.9% and 45.2%, respectively, than other microalgae. Therefore, for cold-water fish and crustacean larvae that require high n-3 PUFA and DHA contents, enrichment of rotifers is desirable at $20^{\circ}C$. Fish larvae would also need more I. galbana than other microalgae.

• Journal of Biosystems Engineering
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• 제43권4호
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• pp.401-409
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• 2018

Decay of fruit is one of the greatest issues in fruit storage. Purpose: In this study, citrus sterilization was performed to evaluate a dry sterilization method using an atmospheric-pressure nonthermal plasma treatment based on a dielectric-barrier discharge technique. Methods: Citrus samples were stored under four different environmental conditions as follows: group A had cold storage with plasma treatment with a temperature of $6.2{\pm}1.0^{\circ}C$ and relative humidity (RH) of $93.4{\pm}8.2%$, group B had ambient-temperature storage with $22.9{\pm}2.3^{\circ}C$ and $82.1{\pm}4.5%$ RH, group C ambient-temperature storage with plasma treatment with $25.3{\pm}2.2^{\circ}C$ and $90.0{\pm}2.8%$ RH, and group D had cold storage with $5.7{\pm}1.0^{\circ}C$ and $93.4{\pm}6.5%$ RH. Results: As a result of citrus surface sterilization by plasma treatment, treatment groups A and C together showed an average of 16.1 CFU/mL of mold colonies, while control groups B and D showed an average of $2.2{\times}10^2CFU/mL$ or approximately 13 times greater than the treatment groups. Regarding the mean concentration of aerobic bacteria colonies, the treatment groups (A and C) and control groups (B and D) showed an average of 7.1 CFU/mL and $1.9{\times}10^3CFU/mL$, respectively. This is approximately a 270-fold difference in the concentration of pathogen colonies between treatment and control groups. Conclusions: The results showed the potential of nonthermal plasma treatment for citrus storage in enhancing storage duration and quality preservation.

• 대한설비공학회지:설비저널
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• 제5권4호
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• pp.272-280
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• 1976

A natural ventilating type store was designed for the economic and effective storage of citrus fruits in Jejudo. The material used for the wall is scoria, widely distributed in Jejudo and known for high strength and insulation. Design condition was chosen for the period till March of a year and the dry bulb temperature was taken from TAC $5\%$ base. The temperature of the store can be maintained below the limiting temperature of $8^{\circ}C$ for the time length of $7\frac{1}{2}$ hours under the condition of the atmospheric temp, $15.3^{\circ}C$ and the solar insolation. The limiting temperature can he recovered to the initial temperature $(7^{\circ}C)$ by the natural ventilation for 8 hours in the night.

• 한국신뢰성학회지:신뢰성응용연구
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• 제9권2호
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• pp.81-91
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• 2009

This paper presents the comparison of climatic environmental tests of IEC Pub. 60068 and MIL-STD-810. Cold, dry heat, change of temperature, and heat-humidity cyclic tests are compared in terms of the types of tests and test severities. This study shows the difference between the standards, which will provide the useful information to the industries and be helpful in applying the standards.

• 한국초지조사료학회지
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• 제21권3호
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• pp.157-162
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• 2001

"Hwasan 102" is a new cold-tolerant Italian ryegrass(Lo1ium rnultiflorum L.) variety developed by theNational Livestock Research Institute(NLRI) in 1999. Having cold tolerance in Italian ryegrass is an importantfor enlargement of cultivation area and increase of productivity in Korea. To develop the cold-tolerant varietyof Italian ryegrass, cold-tolerant clones survived under - 13- - 14$^{\circ}$C of minimum average air temperature(MAAT) in January were selected at Dun Nae, Kwangwon Province in 1993. Five of selected clones werepolycrossed for seed production by NLRI, RDA, in 1995."Hwasan 102" was tetraploid variety, dark green in leaf color and broad in flag leaf width. Also it hassemi-prostrate and medium growth habit in late autumn and in early spring, respectively. "Hwasan 102" withlow plant height at harvesting time was excellent in lodging tolerance. First heading date of "Hwasan 102"was 19th May, it was similar to that of Marshall. Expecially, "Hwasan 102" survived about 60% under - 10- - 12$^{\circ}$C of MAAT in January, so it could be cold-tolerant variety that can be safely cultivated in regionshigher than -9'C of MAAT in January. Compared with Marshall, "Hwasan 102" showed 8% higher freshyield (59.2MT per ha) but it showed 2% lower dry matter yield (9.6MT per ha). Higher IVDMD and TDNand lower ADF and NDF were observed in "Hwasan 102" than those of Florida 80 and Marshall in Foragequality.(Key words : Italian ryegrass, Cold tolerance, New variety "Hwasan 102")rshall in Foragequality.(Key words : Italian ryegrass, Cold tolerance, New variety "Hwasan 102")san 102&")ot;)

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 춘계학술대회
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• pp.962-967
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• 2003

Recently, environmental pollution has become a serious problem in industry, and many researches have been done in order to preserve the environment. The coolant, which promotes lubrication, cooling and penetration, contains chlorine, sulfur and phosphorus to improve the machining efficiency. These additives, which move around into the air during machining, pollute working. Therefore, many researches on how to reduce the amount of coolant during machining have been carried out. However, to reduce even small amount of coolant causes high temperature of a workpiece and it brings thermal defects. In this study, the experiments of wet & dry grinding using cooling methods (using coolant only, mist and compressed cold air only) are performed to solve the problem of environmental contamination and to get a better surface integrity of a workpiece by comparing surface roughness, roundness and residual stress.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2019년도 추계학술대회
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• pp.44-44
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• 2019

Spring sowing of ginseng seeds often results in failure of seedling establishment. Storage condition during winter, sowing time, and seed treatment might effect on germination. Here we tested effects of temperature regimes of seed storage on spring sowing. Dehisced wet or dry ginseng seeds were stored at $2^{\circ}C$, $-2^{\circ}C$, $-3.5^{\circ}C$, or alternating temperature: at $2^{\circ}C$ until December, $-3.5^{\circ}C$ in January, and $2^{\circ}C$ in February, and sowed in March. In overall, emergence rate was dependent on storage temperature, and $-3.5^{\circ}C$ resulted poorest emergence than other conditions. Storage of wet seeds in alternating temperature resulted highest emergence rate. Seed dry also affected on emergence rate, while it was dependent on the storage temperature. In terms of growth, storage at $2^{\circ}C$ as wet seed resulted highest growth, and dried seeds resulted poorer growth than wet seeds. As a modification of alternating temperature, seeds were stored at $2^{\circ}C$ at first, then transferred to $-3.5^{\circ}C$ at Nov 30, Dec 20, and Jan 10, each. When transfer date was delayed, emergence rate was increased. We suggest that seed storage temperature for ginseng should not be decreased below $-2^{\circ}C$, and alternative temperature regime for successful spring sowing could be useful.

• 한국지반공학회논문집
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• 제32권2호
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• pp.53-62
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• 2016

흙의 다짐 특성에 영향을 주는 주요인자 중 하나인 온도는 지역과 계절에 따라 다양하게 변화하는 특성을 가진다. 최근 동토지방에서 많은 토목공사가 시행되고 있지만, 온도와 관련된 흙의 다짐기준 및 지침을 정량화할 수 있는 문헌은 미비한 실정이다. 따라서 본 연구는 온도에 따른 흙의 다짐특성을 시험을 통해 평가하고자 하였다. 시험을 위해 러시아 시베리아, 캐나다 앨버타 주 오일 샌드 지역 등에서 자주 쓰이는 성토재료인 모래의 온도별 다짐특성을 나타낼 수 있는 주문진 모래를 사용하였으며, 표준다짐시험을 흙의 다양한 온도조건($-10^{\circ}C$에서 $17^{\circ}C$)에서 수행하였다. 시험 결과 영상 온도에서는 다짐 시 벌킹 효과로 인해 흙 공시체의 부피 팽창이 발생하였으며, 그 범위는 0%~6%이였다. $0^{\circ}C$에서 $17^{\circ}C$까지 온도가 증가하면서 최대 부피(최소 건조단위중량)에 해당하는 함수비는 감소하였고, 최소 부피(최대 건조단위중량)에 해당하는 함수비는 온도가 증가함에 따라 약간 증가하였다. 영하 온도의 경우 함수비가 추가됨에 따라 건조단위중량은 지속적으로 감소하였다. 영하 온도에서는 벌킹이 발생하지 않았으며 물의 단위부피보다 얼음의 단위부피가 더 크기 때문에 흙 공시체의 부피가 증가하였다.