• Title/Summary/Keyword: Cold Temperature

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Nature of Cold Injury and Resistance in Wheat and Barley (맥류의 한해와 내동성에 관하여)

  • 남윤일;연규복;구본철
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.34 no.s02
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    • pp.96-114
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    • 1989
  • There are several meterorolgical stresses in the winter cereal crops. Among these stresses, cold injury is one of the most important stresses for wheat and barley production in Korea. The reduction in grain yield of the wheat and barley due to cold injury has occurred almost every year in Korea. The objective of the study was to get the basic information in relation to the cold injury and to detect the method minimizing the damage of cold injury. When the air temperature was the ranges of -13$^{\circ}C$ to -15$^{\circ}C$, the soil temperature at the crown part of the plant was very stable, whereas in the ranges of -2$^{\circ}C$ to -3$^{\circ}C$ the soil surface temperature was more unstable and cold than air and subterranean temperatures. The different parts of the plant in wheat and barley possess the different levels of cold hardiness. In comparison to the cold hardiness of plant parts, the leaf and crown are the less sensitive to cold injury than root and vascular transitional zone. The type and extent of stress is determined by the redistribution pattern of water during freezing. These types from freezing processes were three types: a) Equilibrium freezing pattern b) Non -equilibrium freezing pattern, c) Non-equilibrium freezing pattern typical of tender tissues. Cold hardiness in wheat plants were more harder than barley plants at vegitative stage, but inverted at the reproductive stage. Injuries by low temperature during the seasons of barley cultivation in Korea were occured mainly in four stage; in the first and third stage, frost injury occurs, the second stage, freezing injury, and the fourth stage, chilling injury.

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Comparative Assessment of Freshness Preservation in Vacuum-Packed Frozen Olive Flounder Paralichthys olivaceus and Mackerel Scomber japonicus Fillets During Room Temperature Distribution Using Varied Quantities of Commercially Available Cold Packs (시판 보냉팩 개수에 따른 진공포장 냉동 넙치(Paralichthys olivaceus) 및 고등어(Scomber japonicus) 필렛의 상온유통 중 선도유지능 비교평가)

  • So Hee Kim;Ji Un Lee;Eun Bi Jeon;Jin Kim;Pantu Kumar Roy;Shin Young Park;Jung-Suck Lee
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.56 no.6
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    • pp.818-825
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    • 2023
  • The surge in online seafood consumption has increased parcel delivery, leading to a need to implement effective preservation methods. As the cold chain system is not fully established in Korea, styrofoam boxes and cold packs are commonly used for low-temperature seafood distribution. The impact of cold packs on product preservation depends on the number utilized. Herein, the freshness of vacuum-packed frozen fish fillets (Paralichthys olivaceus and Scomber japonicus) stored at 25±0.5℃ for up to 84 h was measured. Chemical (pH and volatile base nitrogen), microbiological (viable cell count), and physical (odor intensity) properties were assessed using 2 or 4 cold packs in a styrofoam box. Four cold packs yielded lower values, indicating superior freshness, and extended fish freshness by approximately 12 h compared with two cold packs. Therefore, it is recommended to use a minimum of 4 cold packs (-350 g/cold pack) in a styrofoam box for distributing approximately 300 g of frozen fish fillets at room temperature during the summer, considering an average delivery period of 2 days in Korea.

Differences in Body Temperatures according to Three Methods of cold Application (냉적용 방법에 따른 심부 및 피부온도변화)

  • 임난영;김진경
    • Journal of Korean Academy of Nursing
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    • v.23 no.2
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    • pp.157-169
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    • 1993
  • The most effective modality for cold application and the length of the application have not been determined despite many studies about the use of cold. A quasi-experimental study was conducted to examine the most effective modality among three methods of cold application, the most effective length of time for the application and the continuing effect after each type of cold application. Thirty adult patients admitted to medical and neurosurgical unit and with high fever (above 38.2 ℃) were assigned randomly to each of three cold ap-plication methods : (a) ice bag: (b) cold compress; and (c) tepid water sponge bath. Each method was applied to the whole anterior surface except the face and neck with the patient in the supine pos-ition. Rectal temperatures and skin temperatures (mid chest, upper arm, thigh and leg) were measured be-fore each application and every 10 minutes during ,each application for a period of 60 minutes. They were also measured every 10 minutes for 30 minutes after each cold application was finished. The experiments were carried out from Dec. 22. 1992 through Feb. 26, 1993. The data were analysed using means, ANCOVA Sheffe test and Pearson's Correlation Coefficient. The results of this study are as follows : 1. There were no significant differences among the three cold application methods in the reduction of body temperature, 2. Among the ice bag, cold compress and tepid water sponge bath groups, the ice bag proved to be the most effective method for lowering skin temperature while the cold compress was least effective. 3. Both rectal and skin temperature continued to decrease during the 60 minutes of cold application, but the hunting phenomena was not observed at any of the cold application sites. 4. There were no significant correlations between mean rectal and skin temperatures. 5. Skin temperatures according to the cold application sites decreased to a range of 3.46℃ to 5.20℃ (mid chest), a range of 4.48℃ 4.96℃ (upper arm), a range of 3.86℃ to 5.05℃ (thigh), and a range of 5.42℃ -7.12℃ (leg ). 6. In continuing effect after the cold applications were finished, rectal temperatures according to ice bag, cold compress and tepid sponge bath decreased to 0.29℃, 0.23℃ and 0.09℃ respectively, while the mean skin temperatures increased to 2.39℃ , 2.04℃ and 2.22℃ respectively. In this experiment the ice bag was the most effective modality for lowering skin temperature. when-ever cold is applied for systemic effect, the continuing effect of cold should be considered. The determination of the most effective length of time for cold application needs further study.

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Improvement of Sliced Raw Fish Texture 1 Effect of Cold Brine Temperature on Sliced Raw Fish Texture (생선회의 육질향상에 관한 연구 1. 생선회 육질향상에 미치는 저온 브라인 온도의 영향)

  • SHIM Kil Bo;LEE Gi Bong;KIM Tae Jin;CHO Young Je
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.36 no.2
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    • pp.69-73
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    • 2003
  • To improve the sensory quality of sliced raw fish, the effect of cold brine temperature on the texture properties was investigated. Fishes were immersed in cold brine by various condition and killed instantly by spiking at the head. The onset of rigor-mortis was accelerated by decrease of immersion temperature. Also, the time reaching full rigor was shortened remarkably too. However, the rigor index of samples immersed in the cold brine decreased more than that of samples killed instantly. Rigor index was the highest in samples killed instantly, followed by $0^{\circ}C,\;-5^{\circ}C,\;-10^{\circ}C,\;-12.5^{\circ}C,\;-15^{\circ}C\;and\;-20^{\circ}C$ in that order. The breaking strength of samples immersed in the cold brine increased slowly but did not increase through all the conditions in the samples. Breaking strength of all samples immersed in the cold brine decreased significantly after reaching the maximum values (p<0.05). The lactate content of muscle was increased by the decreased brine temperature, however ATP content decreased. Minimum lactate and maximum ATP content in fish muscle showed at $-12.5^{\circ}C$. Those results demonstrate that optimal temperature for improvement of sliced raw fish quality by cold brine was $-12.5^{\circ}C.$

Dependence of Round type electrodeless lamp according to ferrite core and cold spot temperature (둥근형 무전극 램프의 페라이트 코어와 냉점의 온도 의존성)

  • Oh, Seul-Yi;Kim, Nam-Goon;Yang, Jong-Kyung;Jung, Young-Il;Park, Dae-Hee
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2009.04a
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    • pp.65-69
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    • 2009
  • Generally Lighting system consists of lamp and luminaire. When a fluorescent lamp is installed in luminaire, power and light output is changed by ambient temperature. Particularly electrodeless lamp depends on the changes that are mercury pressure with amalgam temperature and magnetic properties with ferrite temperature. It has finally influence on optical efficiency. In this study, the temperature change of ferrite and cold spot, vessel are measured at transitional state and then same characteristics are measured with increase of ambient temperature. At transitional state, luminous flux is related to temperature change of cold spot that compare with behavior of mercury pressure and light output. At increase of ambient temperature, we analyzed change that efficiency and electrical, optical characteristics of electrodeless lamp are related to ferrite core and cold spot temperature.

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An Experimental Study on Thermal Properties of Clathrate for Cold Storage Applications (저온축열용 포접화합물의 열물성에 관한 실험적 연구)

  • 한영옥;정낙규;김진흥
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.12 no.8
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    • pp.725-734
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    • 2000
  • The objective of this paper is to investigate the thermal properties of TMA clathrate applicable to cold storage system for building air-conditioning. Especially, the test tube experiments are peformed by comparing and analyzing the temperature of phase change, specific heat and subcooling characteristic according to the variation of concentrations and temperature of heat source in TMA clathrate. The results are summarized as follows; 1) temperature of phase change is dropped as the temperature of heat source is lower, 2) the effect of subcooling suppression with about $9.3^{\circ}C$ is confirmed when the temperature of heat source is $-10^{\circ}C$ in case of 30wt%, while the temperature of subcooling is about $0^{\circ}C$ when the temperature of heat source is $-15^{\circ}C$ in case of 25, 29wt% and 30wt% . Thus, the effect of subcooling suppression is greater as the temperature of heat source is lower. Additionally, the concentrative study is needed on mass concentration causing the phase change without subcooling phenomenon when the temperature of heat source is $-15^{\circ}C$ Thus, it is concluded that TMA clathrate has proper properties as the cold storage medium for building air-conditioning.

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Cold Chain Management in Pharmaceutical Industry: Logistics Perspective

  • Yoon, Yuri
    • Journal of Distribution Science
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    • v.12 no.5
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    • pp.33-40
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    • 2014
  • Purpose - This paper aims to review cold chain management, especially in the pharmaceutical industry, to explore the cold chain process of delivering temperature-sensitive pharmaceutical products, and to identify areas for further development. Research design, data, and methodology - The paper, based on literature review and corporate analysis, reviews the development and status of the cold supply chain system, including its important role in the pharmaceutical industry. Results - Logistics in this field requires more stages than are typically needed. Due to the unique characteristics of the market, few companies can provide the services; currently, only few global companies with large networks and high technologies can afford to do so. Expanding pharmaceutical markets to meet global demand will require cold chain development, especially in "pharmerging" markets. Conclusions - Cold chain is a highly sensitive market in terms of products being carried within the chain that itself is a complex system. However, at the same time, it is a niche market with new opportunities. Hence, a sound cold chain infrastructure is needed to satisfy companies, governments, and customers for both commercial and public reasons.

Identification of the genes which related cold (low temperature) stress in Bombyx mori

  • Kang, Min-Uk;Choi, Kwang-Ho;Park, Kwan-Ho;Nho, Si-Kab
    • International Journal of Industrial Entomology and Biomaterials
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    • v.33 no.2
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    • pp.102-107
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    • 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)

Year-to- Year Variation of Cold Waters around the Korea Strait

  • Min, Hong-Sik;Kim, Young-Ho;Kim, Cheol-Ho
    • Ocean Science Journal
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    • v.41 no.4
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    • pp.227-234
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    • 2006
  • Year-to-year variation of bottom cold waters around the Korea Strait was investigated based on bottom temperatures measured by submarine telephone cable between Pusan, Korea and Hamada, Japan from 1982 to 1992. The characteristics of bottom temperatures could be divided into three different groups: the Korean side, the middle, and the Japanese side. Temperature drops in summer appeared in all the three regions implying the intrusion of cold waters into the Korea Strait. Significant decreases in the Korean side were observed in 1983, 1986, 1990, 1991, and 1992 when bottom temperatures were high in the middle. In contrast, bottom temperatures significantly decreased in the middle in 1985, 1988, and 1989 when the temperature drops in the Korean side were relatively small. This tendency for a negative relationship was also shown in the second mode of an EOF analysis. In the years when bottom temperatures significantly decrease din the Korean side, the cold water along the east coast of Korea expanded offshore and its temperature was low. On the contrary, cold water in the southern region of the Ulleung Basin developed in the years when bottom temperatures decreased considerably in the middle.

A study on coil temperature bariation in 75% hydrogen batch annealing furnace (75% 수소 BATCH 소둔시에서의 코일 온도변화에 관한 연구)

  • Jeon, Eon-Chan;Kim, Soon-Kyung
    • Journal of the Korean Society for Precision Engineering
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    • v.11 no.2
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    • pp.173-181
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    • 1994
  • A Cold spot temperature control system for the batch annealing furnace has been estabilished in order to reduce energy consumption to improve productivity and stabilize the propertics of products. Therefore we confirmed a relation between annealing cycle time and atmospheric gas, variation of coil cold spot temperature with time during heating and actual temperature measurements at mid-width of each coil during heating and actual temperature measurements at mid-width of each coil during soaking. The results of the tempaeature variation effect on the batch annealing are as follows. 1) Heating time is reduced to one half with increasing atmospheric gas flow rate and changing of atmospheric gas component from HNx to Ax gas, and annealing cycle time is reduced to 2.7 times. 2) In case of short time healing, the slowest heating part is the center of B coil, in case of long time heating, the low temperature point moves from the center of coil to inside coil. And the temperature in this part is higher than other parts when cooling. When finished heating, the cold spot is located 1/3 of coil inside in case of HNx atmospheric gas. But center of coil in case of Ax atmospheric gas. 3) The outside of top coil is the highest temperature point when heating, which becomes the lowest temperature point when cooling. So, this point becomes high temperature zone at heating and low temperature zone at cooling, It has relation according to atmospheric gas component and flow rate. 4) Soaking time at batch annealing cycle determination is made a decision by the input coil width, and soaking time for quality homogenization of 1214mm width coil must be 2.5 hours longer than that of 914mm width coil for the same ciol weight. 5) Annealing cycle time with Ax atmospheric gas is extended 1 hour in of slow cooling during 5 hours in order to avoid rapid cooling.

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