• Title/Summary/Keyword: summer environment

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Woody Tissue Respiration in Stems of Red Pine (Pinus densiflora) Trees (소나무(Pinus densiflora) 줄기의 목부조직호흡)

  • Kim, Myung-Hyun;Nakane, Kaneyuki;Na, Young-Eun;Lee, Jeong-Taek
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.9 no.3
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    • pp.203-208
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    • 2007
  • The woody tissue respiration rates in stems ($R_{stem}$) of red pine (Pinus densiflora Sieb. et Zucc.) forest in Higashi-Hiroshima, west Japan, were measured using an open flow measurement system with several chambers in two seasons (the winter and summer in 2002). $R_{stem}$ ranged from 0.25 to $0.55{\mu}mol\;m^{-2}s^{-1}$ in winter, and from 1.25 to $1.63{\mu}mol\;m^{-2}s^{-1}$ in summer. The variability of $R_{stem}$ among the sampled trees (n=15) was similar between the two seasons, with the coefficient variation of about 23%. The numbers of sampling points required to estimate the stem respiration rate within 10 to 20% of its actual value were 24 and 6, respectively in both seasons (probability level is 95%). Based on the relationship between stem temperature and average $R_{stem}$ the $Q_{10}$ values of the winter and summer seasons were 1.49 and 1.45, respectively. The $R_{20}$($R_{stem}$ at $20^{\circ}C$ of stem temperature) was higher in summer ($1.23{\mu}mol\;m^{-2}s^{-1}$) than winter ($0.61{\mu}mol\;m^{-2}s^{-1}$). The woody tissue respiration in stems of red pine trees during the summer season amounted about 50% of the total respiration rates.

Monthly Variation of Water Mass Distribution and Current in the Cheju Strait

  • Pang, Ig-Chan;Hong, Chang-Su;Chang, Kyung-Il;Lee, Jae-Chul;Klm, Jun-Teck
    • Journal of the korean society of oceanography
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    • v.38 no.3
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    • pp.87-100
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    • 2003
  • The monthly observations of hydrography in the Cheju Strait from September 1995 to June 1998 show that the Cheju Strait is occupied mostly by Tsushima Current Water in winter and coastal waters in summer. In summer, the Yangtze Coastal Water appears in the upper layer and cold water in the lower layer. Especially, the Yellow Sea Bottom Cold Water appears in August 1997, and the clockwise flow of warm water along the northwestern coasts of Cheju Island is disturbed by an eastward expansion of the cold water from the northwest. The cold water expansion seems to be partly associated with strong southeasterly winds. Current measurements in the Cheju Strait suggest that there exists steady eastward barotropic component of about 5 cm/sec, which corresponds to 0.2 Sv barotropic transport in the Cheju Strait. Geostropic transport (baroclinic component) ranges from 0.1 Sv in winter to 0.4 Sv in summer. By adding the barotrophic component of 0.2 Sv, the total transport varies from 0.3 Sv to 0.6 Sv, which is consistent with previous estimations. The transport increase in summer seems to be caused by the expansion of coastal water to the Cheju Strait.

Studies on cropping system for year-round forage crops production

  • Kang, Heonil;Lee, Donghyun;Han, Sangcheol;Choi, Insoo;Yun, Eulsoo;Lee, Jongki
    • Proceedings of the Korean Society of Crop Science Conference
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    • 2017.06a
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    • pp.333-333
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    • 2017
  • This study was conducted to establish of cropping system for year-round forage crops production in east-southern part of Korea and investigated their productivity and feed values. Cropping systems were tested in experiment using oat (cv. Highspeed and Darkhorse) in spring and autumn season, corn (cv. Kwangpyeongok) and sorghum (ss-450) in summer season and rye (cv. Gogu) and triticale (cv. Joseong) in winter season. Considering the forage productivity and feed value such as acid detergent fiber (ADF), neutral detergent fiber (NDF) and total digestive nutrients (TDN), this result suggest that three cropping system for year-round forage crops production. The combinations with triticale (winter), corn or sorghum (summer) and oat (autumn) were would be suitable ones. And also the combinations with rye (winter), corn or sorghum (summer) and oat (autumn) were would be suitable. If forage crops cultivation was started in spring season, the combinations with oat (spring), oat (autumn), triticale or rye (winter), corn or sorghum (summer) and oat (autumn) were would be appropriable. For the more suitable cropping system, we are proceeding on verification experiment of year-round forage crops.

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Mathematical and experimental study of hydrogen sulfide concentrations in the Kahrizak landfill, Tehran, Iran

  • Asadollahfardi, Gholamreza;Mazinani, Safora;Asadi, Mohsen;Mirmohammadi, Mohsen
    • Environmental Engineering Research
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    • v.24 no.4
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    • pp.572-581
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    • 2019
  • The emission of hydrogen sulfide (H2S) from the Kahrizak landfill was studied. Firstly, the field measurements were conducted in the summer and winter seasons; and the samples were analyzed using Jacob method. We predicted the H2S concentrations in the downwind using AERMOD and ISCST3. According to the AERMOD, the maximum concentration of H2S in the summer and winter were 117 ㎍/㎥ and 205 ㎍/㎥ respectively. The downwind concentrations reached zero at the distance of 35 km from the leachate treatment plant. The Geometric mean bias, Geometric variance, Fractional bias, Fraction of predictions within a factor of two of the observations and Normalized mean square error for the AERMOD were 0.58, 1.35, -0.12, 1.91 and 0.042, respectively in the summer and 1.39, 1.35, -0.05, 1.46 and 0.027 in the winter; and for the ISCST3, were 0.85, 1.03, 0.02, 1.45 and 0.04 in the summer and 1.18, 1.03, 0.15, 1.16 and 0.04 in the winter. The results of the AERMOD were compared with the ISCST3 and indicated that the AERMOD performance was more suitable than the ISCST3.

Natural Ventilation Planning by Analysis on Air Velocity Property of a Traditional Korean House (한국 전통주거의 기류 분석을 통한 자연통풍 설계 연구)

  • 최윤정;김인선;허범팔
    • Proceedings of the Korean Institute of Interior Design Conference
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    • 2001.05a
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    • pp.117-120
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    • 2001
  • This study is a preliminary research to develop design principles for environmentally friendly housing. The purposes of study are to investigate the literatures related passive design for summer and theory of ventilation, to analyze the indoor airflow patterns in traditional Korean house during summer, and to propose the design factors for effective passive cooling system. The analysis for airflow patterns was focused on the ‘An bang’and the ‘Dae Chung’in the ‘An Chae’of a traditional house located in Seoul. Field measurements of air temperature and air velocity were carried out at 30 different measuring points with 8 different window-opening conditions. The measurements were taken on the hottest summer days in August 2000. It is concluded that from an environmentally friendly standpoint design factors to control indoor thermal environment by a passive cooling system during the summer are as follows; ceiling structure has thermal performance like a time-lag effect, optimum height and length of eaves which can prevent sunlight and divert airflow toward the sitting level, building arrangement acceptable the prevailing wind, strategic window arrangement which makes cross ventilation possible (especially north-south) at the sitting level, window opening condition which is possible to intersect two cross-ventilation stream at the main living areas, northward windows remaining in shade to create the air pressure difference, and planning building shape like a bracket that has optimum width and depth.

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An Overview of Teff (Eragrostis teff Zuccagni) Trotter) as a Potential Summer Forage Crop in Temperate Systems

  • Habte, Ermias;Muktar, Meki S.;Negawo, Alemayehu T.;Lee, Sang-Hoon;Lee, Ki-Won;Jones, Chris S.
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.39 no.3
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    • pp.185-188
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    • 2019
  • The production of traditional cool season grasses in temperate regions is becoming hampered during summer seasons due to water deficit. Thus, incorporating water use efficient warm season annual grasses are generally considered to fill the gap of summer season forage reduction that would offer considerable flexibility and adaptability to respond to forage demand. Teff (Eragrostis teff Zuccagni) Trotter) is, a C4 drought tolerant warm season annual grass primarily grown for grain production, recently gaining interest for forage production particularly during summer season. Previous reports have showed that teff is palatable and has comparable forage biomass and feed quality as compared to other warm season annual grasses which would make it an alternative forage. However, the available data are not comprehensive to explore the potential of teff as forage, hence further assessment of genotype variability and performance along with compatibility study of teff with forage production system of specific environment is key for future utilization.

The first case of summer-type hypersensitivity pneumonitis in Korea (Trichosporon cutaneum에 의한 summer-type hypersensitivity pneumonitis 1예)

  • Lee, Seung-Joon;Kim, Gye-Soo;Lee, Jae-Cheol;Yoo, Churl-Gyoo;Kim, Young-Whan;Han, Sung-Koo;Shim, Y.
    • Tuberculosis and Respiratory Diseases
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    • v.43 no.2
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    • pp.280-284
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    • 1996
  • We report the first case of summer-type hypersensitivity pneumonitis(SHP) in Korea diagnosed by positive serum antibodies to Trichosporon cutaneum. Hypersensitivity pneumonitis(HP) has been commonly classified as an occupational respiratory diseases. However, evidence that sensitizing organisms can also contaminate and cause pulmonary diseases in home environment has been increasing. One such disease is SHP. In Japan, 75% of cases with HP are SHP. Even though there has been no known SHP case in Korea yet, there has been high possibility of SHPs in Korea because our country has areas which have hot and humid summer climate similar to Japan. This first case of SHP in Korea suggests that there may be another cases in Korea and nation-wide survey may be required. We report here the first confirmed case of SHP in Korea.

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