• Title/Summary/Keyword: cold environment

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BIO-GREEN' FUNCTIONAL WATER SUPPLY INFLUENCES MINERAL UPTAKE AND FRUIT QUALITILE IN 'TSUGARU' APPLES (바이오 그린' 기능수 처리가 사과 '쓰가루' 품종의 무기성분 흡수와 과실품질에 미치는 영향)

  • Kim, Wol-Soo;Chung, Soon-Ju
    • Proceedings of the Korean Society for Bio-Environment Control Conference
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    • 1997.05a
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    • pp.23-27
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    • 1997
  • Bio-Green(B.G.) functional water was manufactured by Kyungwon Enterprise Co. through a series of processes ; water longrightarrow ultra-purification longrightarrow adding catalysts longrightarrow energy imprinting fermenting with energized water + zeolite and others + photosynthetic bacteria in fermenter longrightarrow filtering. Control(0), 5 or 10 liters of B.G. functional water were supplied to the orchard soil under canopy of 10 year old 'Tsugaru'/M26 apple trees on March 20, May 20 and June 20, 1995, respectively. Some orchard soil characteristics, not only pH, but also Ca and Mg of exchangeable cations were increased by supply with B.G. functional water. However, P$_2$O$_{5}$, K, and B contents were not influenced by the treatment. At harvest time soluble solid content of flesh and anthocyanin of fruit skin were increased by the treatment. B.G. functional water treatment showed higher root activities, and photosynthesis of leaves than that of control. Also B.G. functional water treatment showed higher Ca content in fruit skin and flesh tissues, whereas not affected N, K, and Mg contents. During storage at 4$^{\circ}C$ cold room, the more volume of B.G. functional water supply showed lower bitter pit symptom. Respiration and ethylene evolution in fruit were decreased, while fruit firmness increased by the treatment during storage.e.

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Overwintering Capacity Affected by Seeding Time and Method of Chinese Milk Vetch, Astragalus sinicus L., in Upland Field

  • Lee Ji Hyun;Kang Byeung Hoa;Shim Sang In
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.50 no.2
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    • pp.67-72
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    • 2005
  • Overwintering capacity, closely related to winter hardiness, of Chinese milk vetch planted with different sowing times and sowing practices was investigated to improve the incorporation into cropping system in Korea. The tolerance to low temperature was evaluated with $LT_50$ using leaf disc leaching method. Dry weight of CMV was reduced remarkably with delayed planting from Sep. 5 to Oct. 20. The differences in tolerance to freezing temperature were not conspicuous among CMV genotypes, however, the differences between genotype (collections at different regions) were due to the plant architecture, mainly to the leaf angle. The crouching genotype collected at central region of Korean peninsula, which showed excellent freezing tolerant, has planophile leaves. The feature of internal constituents of CMV genotypes did not show any noticeable differences with respect to the freezing tolerance which evaluated by leaf disc leaching experiment. To overcome the poor overwintering capacity, tolerant genotype should be developed by selection with considering the plant architecture. The reduction of CMV growth during overwintering period was ameliorated with furrow-sowing under late-sown condition, therefore, when the CMV is inevitably sown late after recommended time, the seeds should be sown on furrow to overcome the cold stress.

Mechanism for Bank Erosion and Local Scouring in Estuary of the Hangang River

  • Lee, Samhee;Han, Hyeongjun;Choo, Jeongho
    • Journal of Wetlands Research
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    • v.16 no.4
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    • pp.453-462
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    • 2014
  • The levee and bridge pier in estuary of the Hangang River are exposed in a dangerous condition due to bank erosion and local scouring occurred since the summer season in 2011. At first, it is presumed that the high sandbar formed in river channel of the study area was an important element in the occurrence of bank erosion and local scouring. It can be presumed that the record-breaking depth of freezing due to cold wave for the long term during the winter season between 2010 and 2011 as well as the heavy intensive rainfall of 2011 had a decisive effect on the first damage of A section. The second damage of B section mainly occurred around the bridge pier constructed on the high water channel before it was washed away during the winter season between 2011 and 2012. It is considered that the second damage was caused by ice formation and ice floes.

Design and evaluation of the thermal capability to secure a working time of cryogenic explosion-proof camera in LNG carrier tank

  • Kang, Geun-Il;Kwak, Si-Young;Park, Chun-Seong
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.9 no.5
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    • pp.568-576
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    • 2017
  • With an increase in the usage of LNG, there is a heightened interest about its safety aspects regarding the explosion of LNG carrier tank. The need for a cryogenic explosion-proof camera has increased. The camera has to work in cryogenic environment (below $-160^{\circ}C$) in LNG carrier. This study conducted design and heat transfer analysis of cryogenic camera to secure working time in limitation of heat source. The design with gap width of double pane windows was conducted based on simple vertical cavity model to insulate from cryogenic environment. The optimal gap width was 12.5 mm. For effective analysis considering convection within the camera, equivalent thermal conductivity method was adopted with ABAQUS. The working time of the camera predicted was over 10 h at warm-start condition. In cold-start condition, it required about 5 h of pre-warming time to work. The results of analysis were compared with the ones of the actual cryogenic test.

Characteristics of Polymer irradiated by Low energy Ion Beam

  • sung Han;Yoon, Ki-Hyun;Jung, Hyung-Jin;Koh, Seok-Keun
    • Proceedings of the Korean Vacuum Society Conference
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    • 1999.07a
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    • pp.109-109
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    • 1999
  • Recently, low energy ion beam irradiation has been adopted for surface modification. Low energy ion beam irradiation has many advantages in polymer engineering such as weak damage, good adhesion, noticeably-enhanced wettability(less than 15 degree), good reproducibility and so on. In this experiment, chemical reactions between free radicals and environment gas species have been investigated using angle-resolved XPS and TRIM code. In the case of low ion beam energy (around 1 keV), energy loss in polymer is mainly originated from atomic collisions instead of electronic interference. Atomic collisions could generated displaced atoms and free radicals. Cold cathode-ion source equipped with 5cm convex grid was used in an O2 environment. Base and working pressure were 5$\times$10-6 and 2.3$\times$10-4 Torr. Flow rates of argon and oxygen were fixed at 1.2 and 8 sccm. target materials are polyethylene polyvinyidenefluoride and polytetrafluoroethylene.

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Thermal Diary - 24 hours' Exposed Temperature and Thermal Comfort in Urban Life, Summer (여름철 도시의 일상생활에서 폭로되는 환경온도와 온냉감 평가)

  • 이민정;전정윤
    • Proceeding of Spring/Autumn Annual Conference of KHA
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    • 2002.11a
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    • pp.333-337
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    • 2002
  • All the outdoor and indoor spaces are connected with each other. The human being moves toward those spaces and experiences temperature fluctuation between the natural and artificial temperature. We conducted an experiment which subjects are the college students wearing the data logger in urban life, and measured 24 hours' exposed temperature and thermal comfort in summer. Results were as follows. 1. Most subjects get weather information(84.6%). Fashion(46.2%) and weather (30.8%) are the reasons to select clothes. They spend their time in indoor environment for 84.92% hours of a day and have an air-conditioner(61.5%) in their houses. 2. Exposed temperature fluctuation were from 33.8$^{\circ}C$ to 15.6$^{\circ}C$. The median value of experienced temperature were 26-27$^{\circ}C$ and average temperature was 26.3$^{\circ}C$. Subjects experienced cold shock of 3.96 times in a day and 67.21% of all evaluated thermal comfort in the range of -1 and 1 by ASHRAE 7 Category Scales. Artificial environment which connected with outside let people experienced temperature fluctuation in wide range.

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The "Warm Zone" Cases: Environmental Monitoring Immediately Outside the Fire Incident Response Arena by Firefighters

  • Caban-Martinez, Alberto J.;Kropa, Bob;Niemczyk, Neal;Moore, Kevin J.;Baum, Jeramy;Solle, Natasha Schaefer;Sterling, David A.;Kobetz, Erin N.
    • Safety and Health at Work
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    • v.9 no.3
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    • pp.352-355
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    • 2018
  • Hazardous work zones (i.e., hot, warm, and cold) are typically established by emergency response teams during hazardous materials (HAZMAT) calls but less consistently for fire responses to segment personnel and response activities in the immediate geographic area around the fire. Despite national guidelines, studies have documented the inconsistent use of respiratory protective equipment by firefighters at the fire scene. In this case-series report, we describe warm zone gas levels using multigas detectors across five independent fire incident responses all occurring in a large South Florida fire department. Multigas detector data collected at each fire response indicate the presence of sustained levels of volatile organic compounds in the "warm zone" of each fire event. These cases suggest that firefighters should not only implement strategies for multigas detector use within the warm zone but also include respiratory protection to provide adequate safety from toxic exposures in the warm zone.

A Research on Algific Sites' Value as Geosites and Their Conservation Strategies (풍혈지대의 지질명소로서의 가치와 보호대책에 관한 연구)

  • Kim, Jeongyun;Park, Kyeong
    • Journal of The Geomorphological Association of Korea
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    • v.23 no.2
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    • pp.15-27
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    • 2016
  • Since restoration of damaged geomorphological sites is almost impossible, it is necessary, to select and conserve geomorphological heritages in a preemptive action. Algific (=producing cold) sites are one of the natural resources which have not been protected well due to the lack of understanding of their value, despite their conservation importance. This research aimed to help people to recognize such geosites' actual value and make them understand the necessity of protecting these sites. Algific areas are valuable by the simple fact that it is a mysterious phenomenon in which the ice forming may happen even in the mid-summer and the environment is always cool. Algific sites deserve geomorphological research in the sense that topographic condition called talus causes this phenomenon. They are also valuable in plant geographic sense because northern rare plants survive isolatedly due to low-temperature environment of these sites. Their cultural-historical value is also high by the fact that they have been connected closely with local residents' lives shown by its nicknames, "natural refrigerator" or "natural air conditioner".

A Study on the Change of Heavy Snow Strength by SST in Influence of Continental Polar Air Mass

  • Park, Geon-Young;Ryu, Chan-Su
    • Journal of Integrative Natural Science
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    • v.7 no.1
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    • pp.39-44
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    • 2014
  • The results of the synoptic meteorological analysis showed that when the cold and dry continental high pressure was extended, heavy snow occurred at dawn when the upper atmosphere cooled. In particular, when the continental high pressure was extended and the upper pressure trough passed through, heavy snow occurred due to the convergence region formed in the west coast area, sometimes in the inland of the Honam area. In addition, it was verified that the changes in the humidity coefficients in the upper and lower layers are important data for the determination of the probability, start/end and intensity of heavy snow. However, when the area was influenced by the middle-latitude low pressure, the heavy snow was influenced by the wind in the lower layer (925 hPa and 850 hPa), the equivalent potential temperature, the convergence field, the moisture convergence and the topography. In Case 2010 (30 December 2010), OSTIA had the best numerical simulation with diverse atmospheric conditions, and the maximum difference in the numerically simulated snowfall between NCEP/NCAR SST and OSTIA was 20 cm. Although there was a regional difference in the snowfall according to the difference in the SST, OSTIA and RTG SST numerical tests, it was not as significant as in the previous results. A higher SST led to the numerical simulation of larger snowfall, and the difference was greatest near Buan in the west coast area.

Effect analysis of ISLOCA pathways on fission product release at Westinghouse 2-loop PWR using MELCOR

  • Kim, Seungwoo;Park, Yerim;Jin, Youngho;Kim, Dong Ha;Jae, Moosung
    • Nuclear Engineering and Technology
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    • v.53 no.9
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    • pp.2878-2887
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    • 2021
  • As the amount of fission product released from ISLOCA was overestimated because of conservative assumptions in the past, several studies have been recently conducted to evaluate the actual release amount. Among several pathways for the ISLOCA, most studies were focused on the pathway with the highest possibility. However, different ISLOCA pathways may have different fission product release characteristics. In this study, fission product behavior was analyzed for various pathways at the Westinghouse two-loop plant using MELCOR. Four pathways are considered: the pipes from a cold leg, from a downcomer, from a hot leg to the outlet of RHR heat exchanger, and the pipe from the hot leg to the inlet of RHR pump (Pathway 1-4). According to the analysis results, cladding fails at around 2.5 h in Pathways 1 and 2, and on the other hand, about 3.3 h in Pathways 3 and 4 because the ISLOCA pathways affect the safety injection flow path. While the release amount of cesium and iodine ranges between 20 and 26% in Pathways 1 to 3, Pathway 4 allows only 5% to the environment because the break location is submerged. Also, as more than 90% of cesium released to the environment passes through the personnel door, reinforcing the pressure capacity of the doors would be a significant factor in the accident management of the ISLOCA.