• 농업과학연구
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• 제40권3호
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• pp.191-196
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• 2013

This study was conducted to investigate the effect of temperature during transportation and continuing shelf-life on fruit quality and the occurrence of physiological disorder to set up the appropriate exportation temperature condition in Asian pear (Pyrus pyrifolia Nakai) 'Hanareum'. In the experiment of simulated exportation headed for USA, the fruits transported at $1^{\circ}C$ showed less weight loss than those of $5^{\circ}C$. Market temperature appeared as a key factor for keeping freshness of exported pear fruits rather than transportation temperature. Quality factors such as high flesh firmness and low incidence of fruit rot and physiological disorders including core breakdown and pithiness were attained at the fruits maintained at $18^{\circ}C$. Approximately two times higher incidence of physiological disorders and of fruit decay rates were observed in the fruits distributed at $25^{\circ}C$ than the those of $18^{\circ}C$. Therefore, temperature management during marketing resulted as an important factor for maintaining fruits quality in the process of pear fruit exportation.

• 한국식품영양과학회지
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• 제27권1호
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• pp.16-23
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• 1998

Effect of Fermentation temperature on the changes of chemical components in Kakudgi during fermentation was investigated by measuring free sugar, organic acid and volatile compounds up to 57 days at several temperatures. The mannitol was increased in palatable period in contrast with those of other free sugars. The higher the initial fermentation temperature was and the longer the initial fermentation time at 2$0^{\circ}C$ was, the faster the second increasing period was and the less the initial contents was. Lactic acid was increased 6~31 times from a little amount at the initial period. The higher the initial fermentation temperature was and the more the increasing content was. But malic acid which was abundant(55.1% of total nonvolatile organic acid) in the initial fermentation period was remarkably decreased in the palatable period. The change of the sulfides among the volatile compounds was remarkable. Methyl allyl sulfide which was a little in the initial fermentation period was remarkably increased in the final fermentation period, and the correlation coefficients between the content of methyl allyl sulfide and aroma in sensory evaluation were high. It could be suggested that the fermentation temperature should be set to 4$^{\circ}C$ after fermentating at 2$0^{\circ}C$ for 36 hours in the view point of keeping the Kakdugi taste and quality well because of high content of free sugar and nonvolatile organic acids.

• 한국식품저장유통학회지
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• 제5권4호
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• pp.339-341
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• 1998

제주산 감귤의 유통방법에 따른 선도 변화를 조사하고 저온유통의 효과를 검토하였다. 유통 중 성분변화는 상온(17$^{\circ}C$)유통이 저온(5$^{\circ}C$)유통에 비해서 중량감소는 6% 증가, vitamin C는 1.91mg 감소, 당산비는 20% 증가함을 보였다. 상온유통에서 중량감소로 인하여 당산비가 높아져서 (16.11에서 21.75) 감귤의 맛과 선도가 감소된다. 현행 감귤수송은 상온유통을 하고 있으나 고품질 감귤에는 부적합한 것으로 나타나며 고품질 소량생산 지향의 생산 체계에 저온유통체계를 도입하는 것이 상품성 향상에 중요 할 것으로 사료된다.

• 한국분무공학회지
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• 제16권3호
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• pp.126-133
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• 2011

In HCCI Engine, combustion is affected by change of compression speed corresponding to engine speed. The purpose of this study is to investigate the mechanism of influence of engine speed on HCCI combustion characteristics by using numerical analysis. At first, the influence of engine speed was shown. And then, in order to clarify the mechanism of influence of engine speed, results of kinetics computations were analyzed to investigate the elementary reaction path for heat release at transient temperatures by using contribution matrix. In results, as engine speed increased, in-cylinder gas temperature and pressure at ignition start increased. And ignition start timing was retarded and combustion duration was lengthened on crank angle basis. On time basis, ignition start timing was advanced and combustion duration was shortened. High engine speed showed higher robustness to change of initial temperature than low engine speed. Because of its high robustness, selecting high engine speed was efficient for keeping stable operation in real engine which include variation of initial temperature by various factors. The variation of engine speed did not change the reaction path. But, as engine speed increased, the temperature that each elementary reaction would be active became high and reaction speed quicken. Rising the in-cylinder gas temperature of combustion start was caused by these gaps of temperature.

• 대한미생물학회지
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• 제6권1호
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• pp.9-13
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• 1971

The bacterial substance inhibited the methylene blue-uptaking activity of red cells. On keeping at room temperature the methylene blue-uptaking activity of red cells sensitized with bacterial substance was more rapidly destroyed than that of normal cells. The methylene blue-uptaking activity of red cells was more inhibited by the supernatant fraction than sediment of bacterial substance.

• Journal of Advanced Marine Engineering and Technology
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• 제32권8호
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• pp.1303-1308
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• 2008

Keeping cooling water temperature higher within the allowable range helps marine engines to run in more efficient condition especially when the engine load is low. Temperature control of jacket cooling water in outlet side of main engine has been more widely adopted to ships these days for the purpose to reduce fuel consumption rate. But If the temperature sensor for the control loop is placed at the outlet of engine, it brings more difficulties in attaining stable and desirable properties due to dead times included in pipe length and engine itself comparing to the case where the measuring point is at the inlet side of main engine. In relation with this problem, Feed-forward control could be one of realistic solutions as it reveals good properties and requires less cost for system configuration. This study suggests a forward control system which leads to improved temperature control performances to disturbance signals which could arise from variation of engine load or weather condition. Two dead times in the modelling were described, considering pipe length between the actuator and the engine as well as the thermal process inside the engine. The results of analysis were shown by simulations to confirm responses under different conditions.

• 소성∙가공
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• 제20권3호
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• pp.243-249
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• 2011

In this study, an approach designed to compute high temperature friction coefficients for SCM 435 steel through a pilot hot rolling test and a finite element analysis, is proposed. Single pass pilot hot flat rolling tests with reduction ratios varying from 20 to 40% were carried out at temperatures ranging from 900 to $1200^{\circ}C$. In the proposed approach, the friction coefficient is calculated by comparing the measured strip spread and the roll force with the simulation results. This study showed that the temperature and reduction ratio had a significant influence on the friction coefficient. As both material temperature and reduction ratio become higher, the friction coefficient increases monotonically. This finding is not in agreement with the Ekelund model, which is widely used in the analysis of the hot rolling process. In the present work, the friction coefficient at a reduction ratio of 40% was found to be 1.2 times greater than that at a reduction of 30%. This higher friction coefficient means that an increment of the roll thrust force is expected at the next stand. Therefore, a roll pass designer must understand this phenomenon in order to adjust the reduction ratio at the stands while keeping the driving power, the roll housing structure and the work roll strength within the allowable range.

• International Journal of Industrial Entomology and Biomaterials
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• 제6권2호
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• pp.197-202
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• 2003

The hot climatic conditions prevailing particularly in summer are not conducive to rear these high yielding bivoltine hybrids throughout the year, In order to select efficiently the breeds with high temperature tolerance, it is very important to analyze critically the impact of high temperature on many silk yielding attributes of silkworm races. Keeping the above in view, the present study was undertaken to determine the effect of high temperature $(36 {\pm} 1^{\circ}C)$ and high humidity $(80 {\pm} 5% Relative Humidity)$ on the rearing performance of pure races, foundation crosses, single hybrids and double hybrids of bivoltine silkworm, Bombyx mori L. The robust bivoltine breeds, CSR18, CSR19, 8HT and 5HT, eight foundation crosses, eight single hybrids and eight double hybrids involving these breeds were chosen as materials in this study.

• Journal of Korean Biological Nursing Science
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• 제17권3호
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• pp.236-244
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• 2015

Purpose: The study was conducted to identify factors affecting the intraoperative core body temperature (CBT) of surgical patients under general anesthesia. Methods: This study was performed through a prospective descriptive research design. The sample consisted of 138 patients who had undergone elective laparotomy surgery. Age, weight, height, the basal preoperative CBT, blood pressure, and heart rate were collected. CBT was again measured at induction of anesthesia, 1 hour, 2 hours, and 3 hours following induction of general anesthesia. Results: Factors affecting intraoperative hypothermia < $36^{\circ}C$ at 1 hour following induction, were CBT at induction and total body fat (TBF) ($R^2=.569$, p<.001); at 2 hours after induction, CBT at induction and TBF ($R^2=.507$, p<.001); at 3 hours after induction, CBT at induction (${\beta}=0.34$), TBF, age and the ambient temperature in the operating room ($R^2=.449$, p<.001). Conclusion: CBT at induction and TBF appear to be factors affecting intraoperative CBT within 2 hours after induction of anesthesia; CBT at induction, TBF, advanced age and the ambient temperature after 3 hours following induction. We recommend keeping surgical patients warm before induction of anesthesia and providing intraoperative warming for surgical patients of advanced age with low TBF and when the duration of general anesthesia will last more than 3 hours.

• 생물환경조절학회지
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• 제15권4호
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• pp.340-345
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• 2006

A potato (Solanum tuberosum L. cv. Superior) cultivar was grown in aeroponic cultivation system to investigate the effect of root zone cooling in summer. Based on their nutrient uptake, growth responses, and tuberization, the possibilities for potato seed production were determined. Although shoot growth and early tuberization increased in the conventional non-cooling root zone system (root zone temperature of $25\pm2^{\circ}C$), stolen growth, photosynthesis, transpiration rate and number of tubers produced were higher in the cooling root zone system ($20\pm2^{\circ}C$) than in the non-cooling system. Increasing root zone temperature above $25^{\circ}C$ stimulated absorption of K more than T-N, P, Ca, Fe and Mn. On the other hand, root zone temperatures in the range of $20^{\circ}C$ to $25^{\circ}C$ did not affect Mg contents. The lower uptake and supply to leaves of T-N, Fe and Mn at the high root zone temperature promoted early tuberization and advanced haulm senescence. The results stress the importance of keeping root zone temperature to as low as below 20, particularly in summer under temperate Bone.