• 한국작물학회지
• /
• 제40권2호
• /
• pp.203-211
• /
• 1995

벼 품종의 내냉성정도를 판정하는데 기준이 되는 몇가지 형질들에 대하여 품종형에 따른 저온반응의 차이를 구명하고자 오대벼외 187개 품종을 공시하여 실험을 수행한 바 그 결과를 요약하면 다음과 같다. 1. 각 품종형에 따라 대부분의 형질에서 서로 상이하면서 다양한 변이를 나타내었는데, 자포니카형 과 인디카형 에서 는 냉해에 강한 품종이 많은 반면, 통일형 품종은 대부분의 형질에서약한 반응을 나타냈다. 2. 적고현상은 대부분의 자포니카형 품종에서 강한 쪽으로, 통일형 품종은 약한 쪽으로, 그리고 인디카형 품종은 강한 것에서 약한 것까지다앙한 변이분포를 나타냈다. 3. 공시한 품종들간에 증감의 차이가 가장 적게 나타난 형질은 수수와 영화수였으며, 특히 가수는 품종형에 관계없이 188개 품종 중 34개 품종이 냉수구에서 오히려 증가되었다. 4. 출수의 지연, 간장의 단축, 이삭추출도 불량 및 억책율 저하 등에서 통일형 품종은 대부분 그 정도가 심한 반면, 자포니카형 품종과 인디카형 품종에서는 공히 저온반응이 강한 것에서 약한 품종까지 광범위한 변이분포를 나타냈다.

• 한국의류학회지
• /
• 제43권6호
• /
• pp.866-876
• /
• 2019

This study examined the physiological and psychological effects of wearing gloves at rest in a cold environment. Seven elderly females participated in two separate trials: wearing gloves (WG) and bare hands (BH). The experiment was conducted for 60 min in a climatic chamber (air temperature 7.8±0.3℃ with 44±2%RH) with a sedentary posture. Microclimate temperature on the left palm was 4.16℃ higher in WG compared to that in BH (p<.1). Microclimate temperature on the chest during the last 5 min increased compared to the initial 5 min only in WG (p<.05). During the last 5 min, skin temperatures at the arm and hand in WG were higher than those in BH (p<.05). There was no statistical difference in the change of rectal temperature between WG and BH. Heart rate in BH was significantly higher compared to the WG (p<.05). Subjects also felt less cold on the whole body and hand in WG than those in BH (p<.05). The findings indicate that wearing gloves for elderly females affected the distribution of skin temperature and cardiovascular response in cold environments. Elderly females should be informed about the importance of wearing gloves through the clothing guideline in winter.

• Restorative Dentistry and Endodontics
• /
• 제10권1호
• /
• pp.187-191
• /
• 1984

Vital pulpotomies by conventional method were done in 120 male and female cases between the ages of 20 and 60 who visited to SNUDH. The pulpotomized surfaces were covered by FR paste and clinical symptoms were carefully examined 1 week and 4 weeks later. The results were as follows; 1. There was no distinct difference between male and female as a whole, and pain to cold and hot or percussion was increased by aging. 2. Incidence of pain to cold and hot or percussion in group examined 4 weeks later was slightly increased than in group examined 1 week later. 3. There was no case of pain to cold and hot or percussion over all ages after 1 week, but were 5 cases (male 2, female 3) in 40 age, and were 3 cases (male 1, female 2) in 50 age after 4 weeks. 4. In 20 and 30 age, there was no case of pain to cold and hot or percussion after 4 weeks, also.

• 한국공작기계학회논문집
• /
• 제10권5호
• /
• pp.96-103
• /
• 2001

The quality requirements for thickness accuracy in cold rolling continue to become more stringent, particularly in response to exacting design specification from automotive customers. One of the major impacts from the tighter tolerance level is more unusable product on the head end and tail end of tandem mill coils when the mill is in transition to or from steady state rolling condition. A strip thickness control system for a tandem cold steel rolling mills is composed with blocked non-interacting controller and controllers for strip thickness and tension control of each rolling stands. An intelligent mathematical model included an elastic deformation of strip has been developed and applied to the field in order to predict the rolling force. The simulated results showed that the effect of elastic recovery should be included the model, even if the effect of elastic compression was not important.

• International Journal of Industrial Entomology and Biomaterials
• /
• 제33권2호
• /
• pp.102-107
• /
• 2016

Stress may be defined as any modification of environmental parameters that leads to a response by biological organisms. Stresses that affect biolpgical structures may be nonthermal, such as ultraviolet radiation, pH, or salinity, or thermal. Temperture is one of the major stresses that all living organism face. The major effects of cold(low emperature) are decrease of membrane fluidity and the stabilization of secondary structures of RNA and DNA in the cells, which may effect the efficiency of translation, transcription, and DNA replication. In this study, we focus on discovering the genes that are expressed by the cold(low temperature) stress in the silkworm. In cold(low temperature) stress test, we found 100% survive from cold stress at $0^{\circ}C$ up to 12h and $-5^{\circ}C$ up to 2h, and then, survive rate was rapidly decrease in silkworm. Thereafter two whole genes have selected by SSH(Suppression subtractive hybridization). (GenBank accession : GQ149511, GQ338156)

• 한국축산식품학회지
• /
• 제29권5호
• /
• pp.590-598
• /
• 2009

The aim of this study was to model and optimize the calcium alginate (CA) and microbial transglutaminase (TG) systems to form a cold-set myofibrillar protein (MP) gel containing 0.1 M or 0.3 M NaCl using a response surface methodology. The gel strengths of cold-set and heat-induced MP gels, and cooking yields were measured. All measured parameters showed determination coefficients ($R^2$) above 0.7 without a lack-of-fit. The CA system had the best results with component ratios of 1.0:0.3:1.0 corresponding to sodium alginate, calcium carbonate and glucono-$\delta$-lactone, respectively, and was favourable at 0.1 M NaCl. In contrast, the TG system only had an effect on cold-set MP gelation at 0.3 M salt, and the optimal ratio of TG to sodium caseinate was 0.6:0.5. By combining the two systems at 0.3 M NaCl, an acceptable cold-set MP gel with an improved texture and high cooking yield could be formed. Therefore, these results indicated that the functionality of the cold-set MP gel could be enhanced by combining these two optimized gelling system.

• 설비공학논문집
• /
• 제29권3호
• /
• pp.134-141
• /
• 2017

The purpose of this study was to analyze physiological changes via a cold air reaction experiment to generate basic data that are useful for the development of an automobile active air conditioning system to prevent drowsiness. The $CO_2$ concentration causing drowsiness in vehicle operation was kept below a certain level. Air was blown to the driver's face by using an indoor air cooling apparatus. Sleepiness and the arousal state of the driver in cold wind were measured by physiological signals. It was evident in the EEG that alpha waves decreased and beta waves increased, caused by cold air stimulation. The ${\alpha}/{\beta}$ ratio was reduced by about 52.9% and an alert state confirmed. In the electrocardiogram analysis, the efficiency of cold air stimulation was confirmed by the mean heart rate interval change. The R-R interval had a delay time of about one minute compared to the EEG response. The findings confirmed an arousal effect from sleepiness due to cold air stimulation.

• 한국산림과학회지
• /
• 제111권2호
• /
• pp.251-262
• /
• 2022

본 연구는 기후변화에 대응하여 남부지역에서 주로 재배되는 차나무 품종인 '참녹', '보향', '상녹', '명녹'을 대상으로 다수의 내한성 지표를 이용하여 신뢰성 있는 평가를 통해 내한성 차나무를 선발하고자 수행하였다. 저온 피해도 조사결과, -10℃에서 '참녹'과 '보향'은 청고 피해가 조사되었고, '상녹'과 '명녹'은 적고 피해가 조사되었다. 전해질 용출량은 처리 온도가 낮아질수록 그 값이 증가하였다. 비선형 회귀 분석을 통해 치사온도를 예측한 결과 '참녹'(-9.344℃), '보향'(-8.883℃)은 '명녹'(-8.092℃), '상녹'(-7.632℃) 보다 상대적으로 내한성이 강한 것으로 나타났다. Proline 분석 결과 '보향'은 다른 품종들에 비교하여 높게 조사되었고, 항산화 활성도 조사 결과 '참녹'과 '보향'이 저온 처리 시 다른 품종과 비교하여 항산화 활성 수치가 높게 나타났다. 지질과산화 반응 측정 결과 '상녹'과 '명녹'은 저온 처리시 다른 품종과 비교하여 MDA 축적 함량이 높았다. 본 연구 결과 '참녹'과 '보향'은 비선형 회귀 분석을 통해 치사온도를 예측한 결과와 저온피해도, 항산화 활성도, 지질과산화 반응과도 일관성 있게 조사되어 내한성이 강한 것으로 나타났다. 본 연구 결과는 기후변화에 대응한 차나무의 내한성 평가와 선발 뿐만 아니라 내한성 식물의 육성에도 활용될 수 있을 것으로 판단된다.

• 한국소성가공학회:학술대회논문집
• /
• 한국소성가공학회 2001년도 제4회 압출 및 인발가공 심포지엄
• /
• pp.99-106
• /
• 2001

The design for cold extrusion dies is very important, because the die insert is subjected to very high radial and hoop stresses. The design of cold extrusion dies has many constrained conditions. In this paper, the used assumptions are such that the yield strength of each ring is selected according to the allowable tensile or compressive hoop stress in each ring and the maximum allowable inner pressure, when yielding occurs in one ring of the dies, is obtained by the proposed equation. In order to obtain design variables, such as diameter ratios and interferences, using the maximum inner pressure, the flexible tolerance method was used for shrink-fitted thick-walled cylinders. ANSYS APDL was used to perform the repeated analysis of deformation of the dies due to the variation of the design variables. The response surface methodology is utilized to analyze the relationship between the design variables and the maximum radial displacement of the die insert during extrusion. From the results, it is found that outer diameter of the die Insert has the largest effect on the minimization of maximum radial displacement at the inner surface of the dies.

• 방송공학회논문지
• /
• 제15권6호
• /
• pp.845-852
• /
• 2010

클라이언트로부터의 요구메시지의 통계를 바탕으로 하여 방송 서버는 데이터 아이템에 대하여 최적의 컷오프 포인트를 이용하여 핫 아이템과 콜드 아이템으로 나눈다. 핫 아이템은 주기적으로 방송되는데 이 때, 방송 주기는 아이템들의 인기도, 즉 요구확률에 따라 정해진다. 핫 아이템이 방송되지 않은 빈 슬롯에는 적절한 콜드 아이템을 골라 방송하게 되는데, 이 때 대기시간과 대기 중인 요구 메시지의 수 등을 고려하여 콜드 아이템을 정한다. 최적의 컷오프 포인트를 해석적으로 구하기 위하여 평균 응답시간을 컷오프 포인트의 함수로 나타나도록 계산하였다. 요청 도착율과 아이템의 인기도를 변화하면서 수행한 시뮬레이션을 통하여 본 논문에서 제안한 방법이 기존의 방법들보다 더욱 우수한 성능을 나타냄을 보였다.