• Title/Summary/Keyword: Cold day

Search Result 563, Processing Time 0.027 seconds

담배나방의 발생과 휴면에 따른 혈림프 생체물질의 변화

  • 박희윤;이형철;이옥경;박계주;유종명
    • Journal of the Korean Society of Tobacco Science
    • /
    • v.20 no.2
    • /
    • pp.144-152
    • /
    • 1998
  • Changes of biological components in haemolymph of Helicoverpa assulta Guenee were investigated during the development and pupae of cold-stress periods. Protein content was the highest in the larval stage, whereas it showed somewhat lower level at the cold-stressed pupae. The level of free amino acids was high in the larval and adult stages. Althougth decresed in pupal stage, the level of free amino acid remarkably increased at the cold-stressed pupae. Total lipids were a little increased at the pupal stage, after small quantity decreased in I-day old adults, and then remarkably decreased at the cold-stressed pupae. Glycogen was increased at the pupal stage, and somewhat decreased in the stage of adult, but remarkably decreased at the cold-stressed pupae. From thin layer chromatographic analysis, glucose was detected in small quantity at 1-day old pupae, one-day old adults, and cold-stressed pupae, respectively. Each .activity of acid and alkaline phosphatases was the highest in the 1 and 7-day old pupae, respectively, and both enzyme activities were increased about two-fold compared to the activity in the cold-stressed pupae. A total of 2 phosphatase isozymes were observed in throughout the developmental stage, and a new isozyme specific to cold-stressed pupae was identified.

  • PDF

Study of the Curing Time of Cementless Cold Central Plant Recycled Asphalt Base-Layer through Field-Application Review (무시멘트 상온 재활용 아스팔트 기층의 현장 적용성을 통한 양생기간에 관한 연구)

  • Choi, Jun Seong;Jung, Chul Ho;Lee, Chan Hee;Lim, in su
    • International Journal of Highway Engineering
    • /
    • v.19 no.2
    • /
    • pp.67-74
    • /
    • 2017
  • PURPOSES : The objective of this study is to ascertain the curing period of cementless cold central plant recycled asphalt base-layer, using mechanical analyses and specimen quality tests on the field. METHODS : Cold central plant recycled asphalt base-layer mixture was produced in the plant from reclaimed asphalt, natural aggregate, filler for the cold mix, and the modified emulsion AP using asphalt mix design and plant mix design. In order to examine the applicability of the curing period during the field test, the international standards for the possibility of core extraction and the degree of compaction and LFWD deflection were analyzed. Moreover, Marshall stability test, porosity test, and indirect tensile strength test were performed on the specimens of asphalt mix and plant mix design. RESULTS : The plant production process and compaction method of cementless cold central plant recycled asphalt base-layer were established, and the applicability of the optical moisture content for producing the mixture was verified through the field test. In addition, it was determined that the core extraction method of the conventional international curing standard was insufficient to ensure performance, and the LFWD test demonstrated that the deflection converges after a two-day curing. However, the back-calculation analysis reveals that a three-day curing is satisfactory, resulting in a general level of performance of dense asphalt base-layer. Moreover, from the result of the specimen quality test of the asphalt mix design and plant mix design according to the curing period, it was determined that the qualities satisfied both domestic and international standards, after a two-day curing. However, it was determined that the strength and stiffness after three-day curing are higher than those after a two-day curing by approximately 3.5 % and 20 %, respectively. CONCLUSIONS:A three-day curing period is proposed for the cementless cold central plant recycled asphalt base-layer; this curing period can be demonstrated to retain the modulus of asphalt-base layer in the field and ensure stable quality characteristics.

Spatial Distribution Patterns of Winter Daytime and Nighttime Apparent Temperature in South Korea (남한의 겨울철 주.야간 체감 온도의 공간적 분포 특성)

  • 최광용;강철성
    • Journal of the Korean Geographical Society
    • /
    • v.37 no.3
    • /
    • pp.237-246
    • /
    • 2002
  • This study classified wintertime bioclimatic zones of South Korea based on daytime and nighttime distribution of wind chill index calculated from climate data during the coldest month for latest 30 years (1971- 2000). The results show that the winter daytime and nighttime wind chill index were influenced by climatic factors such as elevation, land-sea breeze, topology, and sea currents etc. as well as climatic components such as temperature, wind speed, and sunshine, so that South Korea was divided into five bioclimatic zones; Cool day- cold night zone, Keen day- Cold night zone, Keen day-Very Cold night zone, Cold day and night zone, and Cold day-Extremely Cold night zone. Especially, coasts and island areas, except for south coast of Korea, shows Keen bioclimatic response during daytime and Very Cold bioclimatic response during nighttime. This indicates that coasts and island areas, except for south coast of Korea are affected by moonson and land-sea breeze. In addition, highly elevated Daegwallyeong shows Cold bioclimatic response during daytime and Extremely Cold during nighttime due to the influence of adiabatic temperature lapse rate and monsoon. This study offers basic data necessary to make decisions concerning insulation such as clothing and architect etc. by classifying winter bioclimatic zones of South Korea based on various daytime and nighttime distribution of wind chill.

Comparison of Meat Quality Characteristics and Proteolysis Trends associated with Muscle Fiber Type Distribution between Duck Pectoralis Major and Iliotibialis Muscles

  • Cheng, Huilin;Song, Sumin;Park, Tae Sub;Kim, Gap-Don
    • Food Science of Animal Resources
    • /
    • v.42 no.2
    • /
    • pp.266-279
    • /
    • 2022
  • This study was conducted to evaluate the proteolysis trends and change in meat quality during 10 days of cold storage in duck M. pectoralis major (PM) and M. iliotibialis (IL). Duck IL had a higher pH and greater degree of lightness but lower cooking loss than PM (p<0.05). During the 10-day cold storage, the pH value of PM declined significantly (p<0.05), while the meat quality traits of IL were not affected by cold storage (p>0.05). In PM, the redness increased from day 1 to day 5, while cooking loss was lower on day 10 compared to day 5 (p<0.05). There were no significant differences in the activities of cathepsin B and proteasome 20S during cold storage (p>0.05). The activity of calpains declined gradually during 10 days of storage (p<0.05), and the activity of calpains in PM was higher than that in IL (p<0.05). A total of 5,155 peptides were detected and derived from 34 proteins of duck PM muscle, whereas 4,222 peptides derived from 32 proteins were detected from duck IL muscle. Duck PM muscle was composed only of fast type of muscle fiber, whereas IL muscle was composed of both slow and fast types. The proteins responsible for glycolysis or myofibrillar proteins were closely related to changes in meat color or water-holding capacity during cold storage. These results suggest that changes in meat quality characteristics during cold storage are closely related to protein degradation, which is also related to the distribution of muscle fiber types.

Enhancement of Seed Germination by Aging, Cold-stratification, and Light Quality during Desiccation in Burcucumber (Sicyos Angulatus L.)

  • Kang, Jin-Ho;Jeon, Byong-Sam;Lee, Sang-Woo;Choe, Zhin-Ryong;Shim, Sang-In
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.48 no.1
    • /
    • pp.13-16
    • /
    • 2003
  • Seeds of burcucumber were treated with accelerated aging, cold-stratification, and light quality illuminated during desiccation to enhance their germination and seedling emergence. The germination was increased by aging and cold-stratification although the latter treatment showed greater effectiveness than the former one. In the combined treatment of aging 6 days at $45^{\circ}C$ and cold-stratification, the germination was promoted under longer period of cold-stratification to reach nearly 100% in 3 week cold-stratification on the ninth day from sowing. In the sequentially combined treatment of aging, cold-stratification, and light quality during 24 hour desiccation at $35^{\circ}C$, no-stratified seeds showed the highest rate in red light treatment but the lowest in far-red light. This implies that the phytochrome action run during the desiccation of imbibed seeds. The red light exposure during drying for the cold-stratified seeds after aging accelerated the germination even more than the dark treatment and germinated 100% on the next day of sowing. It is concluded that the sequential treatment of aging, cold-stratification, and red light illumination during desiccation can highly promote percentage and speed of burcucumber seed germination.

The Study of Evaluation for Stability of Serum Free PSA In Vitro

  • Park, Jum Gi;Joo, Kyung Woong
    • Korean Journal of Clinical Laboratory Science
    • /
    • v.45 no.1
    • /
    • pp.5-8
    • /
    • 2013
  • In the specimen of free PSA in the low concentration, the result in % bias from our institution and comparable evaluation institution was -33.7% which is exceeded % bias ${\pm}20%$ ; however, it was the domestically allowable limit recommended by the laboratory accreditation commission for specimen at the low concentration. In this paper, the cause was accredited by instability of free PSA substance within the specimen, and the specimen stability test was performed according to CLSI documents GP29-A2. After the low and high concentration specimen were made, and rapidly cooled down in a deep freezer with $-30^{\circ}C$, serum of two concentrations was measured for 10 consecutive days with 3 times a day by Architect i2000 and observed a change in the mean value. As the results of two groups, there were changes in the established target value, and a change level was evaluated by calculating it with % bias. The low concentration specimen had no significant reduction until the 4 day lapse in cold storage. However, % bias were reduced by -17.5% from the 5 day lapse, by 21.5% after the 7 day lapse, and by -26.9% after the 9 day lapse. The frozen specimen had only intra-day variation for 10 days. In the high concentration specimen, bias began to show as -12.2% from the 3 day lapse in cold storage. There was reduction by -28.9% from the 5 day lapse, by -39% after the 7 day lapse, and by -42.9% after the 9 day lapse. In the frozen specimen, there was only intra-day variation like the low concentration specimen in cold storage.

  • PDF

A Study on the Effect of Cold Water Mass on Observed Air Temperature in Busan (부산지역 기온에 미치는 냉수대의 영향에 대한 연구)

  • Park, Myung-Hee;Lee, Joon-Soo;Ahn, Ji-Suk;Suh, Young-Sang;Han, In-Seong;Kim, Hae-Dong;Bae, Hun-Kyun
    • Journal of the Korean Association of Geographic Information Studies
    • /
    • v.17 no.3
    • /
    • pp.132-146
    • /
    • 2014
  • The effects of the cold air generated from large cold water mass at the coastal area on observed air temperature in Busan were investigated using AWS(Automatic Weather Station) data at the Busan area operated by Korea Meterological Administration and SST(Sea Surface Temperature) data at the Gijang and Busan area operated by Korean National Fisheries Research Development Institute. First, the temperature difference between the coastal area and the city area was about $1^{\circ}C$ during cold water mass day while it was about $0.5^{\circ}C$ if cold water mass was not appeared. Second, for day time, the temperature at the coastal area was about $1^{\circ}C$ lower than that at the city area during cold water mass day, but the difference was only about $0.4^{\circ}C$ without cold water mass. On the other hand, for night time, the temperature at the coastal area was about $1.2^{\circ}C$ lower than that at the city area during cold water mass day and the difference was about $0.9^{\circ}C$ without cold water mass. As a result, temperature differences at night time were higher than those at day time whether or not cold water mass appeared. The reason for higher temperature at night time might be the urban heat island phenomenon.

Relation between the Heat Budget and the Cold Water in the Yellow Sea in Winter (동계의 열수지 황해냉수와의 관계)

  • Han, Young-Ho
    • Journal of the Korean Society of Fisheries and Ocean Technology
    • /
    • v.14 no.1
    • /
    • pp.1-14
    • /
    • 1978
  • To study the fluctuation of cold water in the East China Sea in summer heat budget of the Yellow Sea in winter was analysed based on the oceanographic and meteorological data compiled from 1951 to 1974. The maintain value of insolation was observed in December($160{\sim}190ly/day$), while the maximum in February ($250{\sim}260ly/day$). The range of the annual variation was found to be less than 50 ly/day. The value of the radiation term ($Q_s-Q_r-Q_h$) was remarkably small (mean 20 ly/day) in winter. It was negative value in December and January, and a positive value in February. The minimum total heat exchange from the sea ($Q_({h+c}$) was found value (471 ly/day) in February 1962, and the maximum (882 ly/day) in January 1963. The annual total heat exchange was minimum (588 ly/day) in 1962, and maximum (716 ly/day) in 1968. If the average deviation of mean water temperature at 50m depth layer were assumed to be the horizontal index ($C_h$) of colder water, $C_h$ is $C_h=\frac{{\Sigma}\limit_i\;A_i\;T_i}{{\Sigma}\limit_i\;A_i}$ where $A_i$ denotes the area of isothermal region and $T_i$ the value of deviation from mean sea water temperature. The vertical index ($C_v$) of cold water can be expressed similarly. Consequently the total index (C) of cold water equals to the sum of the two components, i.e. $C=C_h$$C_v$. Taking the deviation of mean sea surface temperature(T'w) in the third ten-day of Novembers in the Yellow Sea as the value of the initial condition, the following expressions are deduced : $C-T'w=32.06 - 0.049$ $\;Q_T$ $C_h-T'w/2=12.20-0.019\;Q_T$ $C_v-T'w/2=18.07-0.027\;Q_T$ where $Q_T$ denotes the total heat exchange of the sea. The correlation coefficients of these regression equations were found to be greater than 0.9. Heat budget was 588 ly/day in winter, and minimum water temperature of cold water was $18^{\circ}C$ in summer of 1962. The isotherm of $23^{\circ}C$ extended narrowly to southward up to $29^{\circ}N$ in summer. However, heat budget was 716 ly/day, and minimum water temperature of cold water was $12^{\circ}C$ in summer of 1968. The isotherm of $23^{\circ}C$ extended widely to southward up to $28^{\circ}30'N$ in summer. As a result of the present study, it may be concluded that the fluctuation of cold water of the East China Sea in summer can be predicted by the calculation of heat budget of the Yellow Sea in winter.

  • PDF

Synoptic Characteristics of Cold Days over South Korea and Their Relationship with Large-Scale Climate Variability (한반도 혹한 발생시 종관장 특성과 대규모 기후 변동성 간의 연관성)

  • Yoo, Yeong-Eun;Son, Seok-Woo;Kim, Hyeong-Seog;Jeong, Jee-Hoon
    • Atmosphere
    • /
    • v.25 no.3
    • /
    • pp.435-447
    • /
    • 2015
  • This study explores the synoptic characteristics of cold days over South Korea and their relationship with large-scale climate variability. The cold day, which is different from cold surge, is defined when daily-mean surface air temperature, averaged over 11 KMA stations, is colder than 1-percentile temperature in each year by considering its long-term trend over 1960~2012. Such event is detected by quantile regression and the related synoptic patterns are identified in reanalysis data. Composite geopotential height anomalies at 500 hPa show that cold days are often preceded by positive anomalies in high latitudes and negative anomalies in midlatitudes on the west of Korea. While the formers are quasi-stationary and quasi-barotropic, and often qualified as blocking highs, the latters are associated with transient cyclones. At cold days, the north-south dipole in geopotential height anomalies becomes west-east dipole in the lower troposphere as high-latitude anticyclone expands equatorward to the Northern China and mid-latitude cyclone moves eastward and rapidly develops over the East Sea. The resulting northerlies cause cold days in Korea. By performing composite analyses of large-scale climate indices, it is further found that the occurrence of these cold days are preferable when the Arctic Oscillation is in its negative phase and/or East Asian monsoon circulation and Siberian high are anomalously strong.

An experimental study on the difference of temperature and strength according to member size for cold weather concrete (한중콘크리트의 부재 단면별 온도범위와 강도변화특성에 관한 실험적 연구)

  • Kim, Meyong-Won;Park, Kwang-Su;Cho, Young-Kweon;Lee, Joon-Gu;Kim, Kwan-Ho
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • 2005.05b
    • /
    • pp.421-424
    • /
    • 2005
  • Discusses the results of an investigation of the relationship between maturity in field-cured specimens and that from the thinner dimension structure to thick, particularly at cold weather concrete. Tests were carried out on two different concrete mixes with 28 day compressive strengths ranging approximately 30MPa. Ready-mixed concrete was used, and test specimens were the conventional field-cured 10$\times$20cm concrete cylinder with insulating materials and without them, and test structures were the thinner(width 20cm), the general(width 40cm), the thick dimension(width 60cm), respectively. Tests were performed at age of 3, 7, 14, 28 day. Analyses of test results show that the maturity of concrete for require compressive strength was suggested to be keep higher than $164D^{circ}D$ until at least from 8day to 10day

  • PDF