• Title/Summary/Keyword: Cold Former

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Peasant Societies in Colonial East Asia: The Universality and Particularity of Southeast Asia and Northeast Asia (식민시대 동아시아의 소농사회: 동남아와 동북아의 보편성과 특수성)

  • Park, Sa-Myung
    • The Southeast Asian review
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    • v.22 no.2
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    • pp.1-41
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    • 2012
  • The peasant societies of East Asia had been challenged by capitalist plantation since colonization and by socialist collectivization since decolonization. The former was decisively weakened due to the crisis of the capitalist system in the 1930s and the collapse of the colonial order in the 1940s; The latter was thoroughly discredited due to the reform of the socialist system in the 1980s and the end of the Cold War in the 1990s. The failure of the two epochal challenges demonstrates the historical sustainability of peasant societies in East Asia. Their survival represents the universality of Northeast and Southeast Asia, which can be ascribed to the ecological environment and production process of wet-rice agriculture for their common staple food. In spite of their diverse differences, indeed, peasant societies in colonial East Asia shared profound similarities in their basic motivations (morality-rationality), central tendencies (involution - polarization), structural outcomes (dualism - pluralism), and future prospects (survival-extinction).

Debonding strain for steel-concrete composite slabs with trapezoidal metal deck

  • Claudio Bernuzzi;Marco A. Pisani;Marco Simoncelli
    • Steel and Composite Structures
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    • v.49 no.1
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    • pp.19-30
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    • 2023
  • Steel-concrete composite slabs represent a very efficient floor solution combining the key performance of two different materials: the steel and the concrete. Composite slab response is governed by the degree of the interaction between these two materials, mainly depending by chemical and mechanical bond. The latter is characterized by a limited degree of confinement if compared with the one of the rebars in reinforced concrete members while the former is remarkably influenced by the type of concrete and the roughness of the profiled surface, frequently lubricated during the cold-forming manufacturing processes. Indeed, owing to the impossibility to guarantee a full interaction between the two materials, a key parameter governing slab design is represented by the horizontal shear-bond strength, which should be always experimentally estimated. According to EC4, the design of the slab bending resistance, is based on the simplified assumption that the decking sheet is totally yielded, i.e., always in plastic range, despite experimental and numerical researches demonstrate that a large part of the steel deck resists in elastic range when longitudinal shear collapse is achieved. In the paper, the limit strain for composite slab, which corresponds to the slip, i.e., the debonding between the two materials, has been appraised by means of a refined numerical method used for the simulation of experimental results obtained on 8 different composite slab types. In total, 71 specimens have been considered, differing for the properties of the materials, cross-section of the trapezoidal profiled metal sheets and specimen lengths.

Growth Characteristics and Dry Matter Yields of Domestic and Foreign Italian ryegrass (Lolium multiflorum Lam.) Cultivars in Cheonan Region (천안지역에서 이탈리안 라이그라스 국내육성 품종과 외국품종의 생육특성 및 수량성)

  • Kim, Ki-Yong;Choi, Gi Jun;Lee, Sang-Hoon;Hwang, Tae-Young;Lee, Gi-Won;Ji, Hee Chung;Park, Sung Min
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.36 no.4
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    • pp.280-286
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    • 2016
  • This study was conducted to evaluate the growth characteristics and dry matter yields of Italian ryegrass (Lolium multiflorum Lam., IRG) cultivars for three years (2011~2013). The cold-resistance of domestic cultivars was stronger than other foreign varieties. Among early-maturing cultivars, dry matter (DM) yield of 'Kowinearly' was significantly higher (8,751 kg/ha) than other cultivars (p<0.05). In medium-maturing cultivars, DM yield of 'Kowinmaster' and 'Tam 90' was 9,394 and 7,461 kg/ha, respectively. Of the two, the former's DM yield was higher than the latter's (p<0.05). Among late-maturing cultivars, DM yield of 'Hwasan 104' (9,809 kg/ha) was similar to 'Hwasan 101' (9,354 kg/ha), but significantly higher than the other late-maturing cultivars (p<0.05). According to the results obtained from present study, early-maturing cultivars with cold-tolerance and high productivity is required for the paddy field cultivation of an Italian ryegrass cultivar after rice harvest in Cheonan region. Medium- and late-maturing cultivars are more advantageous for the dry field cultivation of the maximum quantity that is possible. In conclusion, to select which cultivar/s to grow, the climate of the growing area, weather conditions, and the cropping system must all be considered.

Growth Characteristics and Yield Comparisons of Domestic and Foreign Italian ryegrass (Lolium multiflorum Lam) Varieties in Yecheon area of Korea (예천지역에서 이탈리안 라이그라스 국내육성 품종과 외국품종의 생육특성 및 수량성 비교)

  • Kim, Ki-Yong;Lee, Sang-Hoon;Ji, Hee Chung;Hwang, Tae-Young;Lee, Ki-Won;Park, Sung Min
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.35 no.1
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    • pp.43-49
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    • 2015
  • This experiment was conducted to evaluate the agronomic characteristics and forage productivity of Italian ryegrass cultivars in Yecheon, Kyeongbuk from 2011 to 2013. The experimental design was a randomized complete block design (RCBD) with three replications. Italian ryegrass cultivars were seeded on Sep. 26 in 2011 and Sep. 25 in 2012. The Italian ryegrass cultivars were harvested on the heading date of the variety. The cold-resistance of domestic cultivars was stronger than other foreign varieties. Among early-maturing cultivars, the dry matter (DM) yield of the "Kowinearly" was 10,031 kg/ha, which was significantly higher than that of other cultivars (p<0.05). In medium-maturing cultivars, the DM yield of the "Kowinmaster" and "Tam 90" were 10,484 and 8,191 kg/ha, respectively. Of the two, the former's DM yield was higher than the latter's (p<0.05). Among late-maturing cultivars, the DM yield of "Hwasan 104" was 10,641 kg/ha, which was similar to that of "Hwasan 101" and significantly higher than the other late-maturing cultivars (p<0.05). According to the results obtained from this study, an early-maturing variety with cold-tolerance and high productivity is required for the paddy field cultivation of an Italian ryegrass cultivar after rice harvest in the mid-northern region of Korea. A medium- or late-maturing variety is more advantageous for the field cultivation of the maximum quantity that is possible. In conclusion, to select which variety/ies to grow, the climate of the growing area, weather conditions, and the cropping system must all be considered.

Studies on the Varietal Differences of Tolerance to Cold Damage in Seedling Stage of the Rice Plant (수도 유묘기 내냉성의 품종간 차이에 관한 연구)

  • Chung-Ik Cho;Seong Kuk Bae
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.21 no.1
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    • pp.35-42
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    • 1976
  • In Korea, two types of rice varieties are being cultivated widely, Japonica and Japonica-Indica cross. Generally speaking, the latter shows weak cold tolerance than the former and so brought about many problems in cultural practices. This study was conducted to investigate the effect . of various temperature conditions on rice seedlings growth, especially the contents of chlorophyll and the percentage of nitrogen. And the result obtained indicated the varieties of Japonica-Indica intend to weak cold tolerance than Japonica varieties.

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A Study on the Effectiveness of Wind Corridor Construction forImproving Urban Thermal Environment: A Case study of Changwon, South Korea (도시 열환경 개선을 위한 취약지역 선정 및 바람길 조성 방안: 창원시를 대상으로)

  • Kim, Jong-Sung;Kang, Jung-Eun
    • Journal of Environmental Impact Assessment
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    • v.30 no.4
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    • pp.187-202
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    • 2021
  • This study examined the effectiveness of wind corridor construction by analyzing the thermal environment, cold air generation, ventilation, and geographical characteristics to improve urban thermal environment and establish the basis for specialized strategy in Changwon-si, Gyeongsangnam-do. Using spatial analysis and remote sensing techniques, surface temperature, land cover and land use, wind field, and slope were measured and through this, a wind corridor analysis model was constructed. As a result of the analysis as of 2020, Changwon-si generally has land cover characteristics that are advantageous for the generation of cold air, but the temperature in most urban areas is the highest, and the temperature in areas such as north Changwon area, Jinbukmyeon, Ung-dong, and Ungcheon-dong are relatively high. There was a typical trend of high average wind speed in mountain regions and low average wind speed in urban areas. Accordingly, the north Changwon area, the former Changwon downtown area, the Hogye-ri and Pyeongseong-ri areas, and the Changpo Bay area are derived as vulnerable areas to thermal environment, and various measures to reduce temperature and improve air quality that the inflow of cold air into the area considering the characteristics of each area and securing wind ventilation between the surrounding mountains, reservoirs, and park areas were proposed.

Studies on Growth Characteristics and Shallow Green-Roof Systems of Sedum album L. Introduced in Korea (국내에 도입된 Sedum album L.의 생육 특성 및 저토심 옥상 녹화 시스템에 관한 연구)

  • Kim In-Hye;Huh Moo-Ryong;Huh Keun-Young
    • Journal of the Korean Institute of Landscape Architecture
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    • v.33 no.5 s.112
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    • pp.69-82
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    • 2005
  • These studies were carried out (1) to investigate the growth characteristics of Sedum album L. in the field, (2) to propose a suitable shallow peen roof system for this plant, and (3) to evaluate plant growth in the proposed system over the long term. The growth characteristics, such as morphological properties, growth habit, shade tolerance, and flowering, were surveyed. In experimental shallow green-roof systems, the effects of drainage type, substrate type, and soil depth on plant growth were investigated. Then drought tolerance was investigated. After planting Sedum album L. in the proposed system survival rate, cover, and resistance to insects, heal and cold were evaluated for about 2 years. The results of these studies are summarized below. 1. In the field, the aboveground part of Sedum album L. did not die back during the winter. Plant height was 4$\sim$7 cm. Roots were distributed to a depth of 5$\sim$7 cm. Sedum album L. is a compact ground-cover plant that spreads vigorously. Shading condition of less than $30\%$ of full sunlight didn't cause any trouble, but shading conditions above $87\%$ made the shape of the shoots and leaves abnormal. The plant bloomed from June to August and had a rather large compound umbel of white, star-shaped flowers. 2. Two systems, a drainage-blend-10 cm soil depth and a reservoir$\cdot$drainage-blend-15 cm soil depth, performed best in terms of cover, fresh weight, and dry weight. The first has an advantage for green roofs because it is lighter than the latter. 3. In drainage-blend-10 m soil depth and modified reservoir · drainage-blend-10 cm soil depth system no plants died for about 4 months after stopping the irrigation. The visual quality of the latter system was above 5 for 4 months and that of the former was under 5 after 2 months. In the field, however, the drought tolerance of Sedum album L. grown in the former would be enough to withstand the dry season. Considering the urban ecosystem and the importance of healthy growth the modified reservoir $\cdot$ drainage-blend-10 cm soil depth system was finally recommended. This system was composed of a 4 cm thick drainage layer and drain outlets placed at a height of 2.5 cm. 4. In the proposed system, the survival rate was $100\%$, and there was no injury induced by insects and heat. The leaf density decreased a little in winter. Cover increased throughout the year. Sedum album L. was planted with a cover of 72$cm^{2}$ on 3 April 2003; on 16 June 2003 and 15 June 2004, cover was $132.66\pm$5.87 $cm^{2}$(1.8 times) and $886.98\pm$63.51 $cm^{2}$(12.3 times), respectively.

A Relationship between Oceanic Conditions and Meteorological Factors in the Western Sea of Korea in Winter (동계 서해의 해황과 기상인자와의 관계)

  • Go Woo-Jin;Kim Sang-Woo;Kim Dong-Sun
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.12 no.1 s.24
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    • pp.23-32
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    • 2006
  • This study was conducted to find out the effects of meterological factors on oceanic conditions when cold and dry continental air mass passes through the western sea of Korea The change of ocean conditions during the winter season were more obvious in coastal area than open sea And sea surface temperature (SST) during February is lower by $3^{\circ}C$ than December but in coastal area SST dropped by $3^{\circ}C$. As for the salinity, there was not much difference between areas except southern area of Mokpo. In the coastal regions, air temperature(AT) and SST showed a positive correlation; as the air temperature goes up with the increase of SST and when the former goes down the latter decrease. SST of open sea seems to be changed by latent (Qe) and sensible heat (Qs), when the open sea lose its heat by Qe and Qs then SST goes down And when they get the heat then the SST goes up. 1here was a positive correlation between the AT of the coastal region and sea surface salinity (SSS), when the AT goes up then SSS increase and when the former goes down the latter decrease. Precipitation during the summer seasons (June$\sim$September) appeared to the more closely related with salinity of February of the following year than those of October and December.

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Isolation of the Anti-tumor Promoters from Citrus Peels (감귤과피로부터 발암 promotion 억제활성성분의 분리)

  • Yoon, Chang-Hoon;Jwa, Seung-Mi
    • Applied Biological Chemistry
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    • v.49 no.1
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    • pp.25-29
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    • 2006
  • This study was carried out to isolate the possible anti-tumor promoters from the citrus peel (Citrus natsudaidai Hayata). We fractionated the cold-pressed oil of citrus peel by column chromatography, HPLC and TLC. The analysis on column chromate-graphy yielded seven peaks $(F-I{\sim}F-VII)$, all of which showed single spot on TLC analysis ($R_f$ for $F-I{\sim}VIII$; 0.31, 0.13, 0.13, 0.78, 0.79, 0.69 and 0.84). Among the seven fractions, three fractions (F-I, -II and F-IV) were re-analyzed on HPLC, also showing single peak except for one fraction (F-IV) which was divided two peaks. The retention times $(R_f)$ of F-I and F-II was 3 min. and 2.5 min., respectively, but these of two peaks from F-IV were 2 min. and 4.5 min., respectively. Since the area of the latter peak (4.5 min.) was very smaller than that of the former one (2 min.), it is considered that the latter one did not appear on TLC analysis. The inhibitory effect on tumor promoter 12-O-tetradecanoylphorbol-13-acetate(TPA)-induced Epstein-Barr virus activation in Raji cells was tested for the seven fraction obtained. It decreased in order of F-VI (82.3+1.3%) > F-I (80.4+1.6%) > F-II (77.2+0.9%) > F-III (75.0+1.2%) > F-IV (74.1=1.0%) > F-V (71.0+1.1%) > F-VII (70.2+1.2%). These results imply that some constiuents contained in citrus peels have the inhibitory activity of TPA-induced tumor promotion.

A study on Supply Extension Device of AED (AED의 보급 확대 방안에 관한 연구)

  • Koh, Jae-Moon;Kim, Young-Ho;Han, Sang-Hak
    • The Korean Journal of Emergency Medical Services
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    • v.9 no.2
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    • pp.147-168
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    • 2005
  • It examined the doubt point which AED motive relates until now, the AED should have bought a life how, present address of our country site pre-hospital care, comparison it tried to observe the advanced nation instance back. Gist of this research the AED important cold region once compared to informed to how many cardiac arrest patient, against him the what kind of preparation wanted informing the necessary cold region. It soaks simultaneously but the AED motive is widely supplied distant in future and it is generality and it is feeble but it wanted doing one morning. The habit difference of an American who does of course meat diet mainly and a Korean is many and it compares in the United States and the cardiac arrest patient comparison occurs holds a point few. To become Western anger but and be caused by with thin dietary life, stanching bleeding cung, with the fact that the heart attack is increasing rapidly with the hyperextension. It is a talk which anyone it knows all. The major league most Choi huy Sub in condition will catch the ball which floats and the multi co-player and to collide when falling down, the medical device which is committed with emergency aid is AED motive. From the United States subway station and the shopping which are a public place on the baseball field outside the jar which it will drive, the museum and the school, easily there is it will be able to discover the AED from the court of justice back. The Pittsburg university the students per the individual $30 the core phyey were receiving the smallness lifestyle alcoholic beverage and a AED motive actual training with mercy of degree. From the United States distant in future the AED motive is sold even from the retail store and. From our country like this plan government offices temporary disposal education from from 119 fire fighters emergency structure company in fire fighting government employee and nursing must magnify a former enterprise rainy spell in summer multi temporary disposal education with the head which it will burn with the head. This plan in early rising will be able to become fixed in Korea it forecasts with the fact that. The research which it sees it leads and like the United States to some day become fixed even from our country to believe and suspicion it is not and in the people in approach ease one AED supply plan fire fighting government employees stand in the first and feed with the fact that must be positive at this enterprise they become.

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