• Asian-Australasian Journal of Animal Sciences
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• 제10권3호
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• pp.298-303
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• 1997

Sixteen holstein heifers were employed to study the effect of thermal stress on rectal temperature and mineral status of heifers around parturition during hot and cool weather. During the hot weather, rectal temperatures of the heifers measured at 08:30 and 15:30 h from 7 d prepartum to parturition were higher than those during the cool weather. Blood hematocrit and hemoglobin were not significantly different between the hot and cool weather, but at 2 and 1 wk prepartum, those during the hot weather were higher. Plasma Ca, inorganic P and Fe of the heifers during the hot weather were higher than those during the cool weather, but plasma Mg and Zn and serum alkaline phosphatase during the hot weather were lower. Colostral protein and Mg of heifers at parturition during the hot weather were lower than those during the cool weather, but colostral Ca, P, Fe and Zn were not affected by the weather.

• 한국도로학회논문집
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• 제19권3호
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• pp.1-10
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• 2017

PURPOSES : This paper focuses on strength development according to the mix design with cement type and mineral admixture from laboratory and field tests in cool weather. METHODS : Two methods evaluated the mix design of concrete pavement in cool weather. Firstly, laboratory tests including slump, air contents, setting time, strength, maturity, and freezing-thawing test were conducted. Three alternatives were selected based on the tests. Secondly, a field test was conducted and the optimum mix design in cool weather was suggested. RESULTS : It is an evident from the laboratory test that a mix with type III cement showed better performance than the one with type I cement. There was a delay in strength development of a mix with mineral admixture compared to mix design without any mineral admixture. In the field test, type III cement+flyash 20% mix design proved the best performance. CONCLUSIONS : For concrete pavement in cool weather, mix design using type III cement could overcome the strength delay due to mineral admixture. Moreover, it is possible to make sure of durability of pavement. Therefore, strength and durability problems due to cool weather would decrease.

• 한국도로학회논문집
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• 제19권3호
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• pp.11-18
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• 2017

PURPOSES : This study investigates the effect on concrete pavement accordance with the curing methods in cool weather and supports the best method in the field. METHODS : Two field tests evaluated the curing methods of concrete pavement in cool weather. Firstly, five curing methods were tested, including normal curing compound, black curing compound, bubble sheet, curing mat, and curing mat covered with vinyl. Concrete maturity was compared from temperature data. Secondly, normal curing compound and curing mat with vinyl, which showed the best performance, were compared in terms of maturity and join condition index. RESULTS:From the field tests, it is an evident that curing mat with vinyl accelerated the concrete strength. Therefore, it is possible to conduct saw-cut works in cool weather, which minimizes damage on concrete at joint. CONCLUSIONS : For concrete pavement in cool weather, using curing mat with vinyl as the curing method could overcome the strength delay. Therefore, strength and durability problems on concrete at joint due to cool weather would be fewer in the future.

• 한국작물학회지
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• 제27권4호
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• pp.291-295
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• 1982

The biosphere of the earth is not only about to overpass the limit to meet the food demand of the world but also the stability of its food production has been also jeopardized by the disasters and pests, especially by the unpredictable weather disasters. In addition the agricultural and industrial pollution against biosphere aggravates the unstability of agricultural production and constitutes a threat in securing the food of the world. In Korea the yield level of crops has been greatly enhanced by the improved agrotechnologies and varietal improvement, but the yield variability due to unfavorable weather events and pests remained unchanged with the change in time. Among weather-related disasters the drought and flood damages has occurred most frequently and impacted most greatly on the agricultural production and its stability. During last decade (1970-l980) the rice production experienced the average annual loss of 0.544 million metric ton which was composed of 0.21 million M/T by climatic disaster, 0.21 million M/T by disease and 0.12 million M/T by insects, and the annual loss of upland crop production from climatic disasters amounted to 0.06 million metric tons. Especially in 1980, the global climatic disasters due to cold or hot temperature endangered the agricultural production all over the world and also the rice production of Korea recorded the unprecedented yield reduction of about 30 percent due to cool summer weather. Nowadays, the unusual weather conditions are prevaling throughout the world, and agro-meteologists predict that the unpredictable cool summer and drought will often attack the rice and other crops in 1980's. To meet the coming weather unstability and to secure the stable crop production, multilateral efforts should be rendered. Therefore, the Korea Society of Crop Science, which commemorates the 20th anniversary of its founding, prepared the symposium on Meteological Stress in Crop Production and its Countermeasures to discuss the decrease in agricultural production due to weather-related disasters and to devise the multilateral counter-measures against the unfavorable weather events.

• 물과 미래
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• 제5권2호
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• pp.17-29
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• 1972

The persent study aims at finding out a means of prevention cool spell damages on the hilly areas. The irrigation plots of 24 hour stored water warm water way and warm water plots, cool water way are respectively established to find out water temperature and influnce on the growing rice plants. The results obtained are summed up as follows. 1. Warm water areas consisted of $5 m^2 Q=0.93 1{\ell}/sec$, V=31 cm/sec, S=1/1, 000, L=81.6m, B=5cm, h=6cm, t=4min 33sec, drops=9 areas, are constructed to help the water temperature of $14.5^{\circ}C$ rise to that of $21.6^{\circ}C$. This indicates lower temperature than $23^{\circ}C$ of critical water temperature in irrigation facilities by $1.45^{\circ}C$ and than $26.2^{\circ}C$ of balanced water temperature of Seoul arears by $4.6^{\circ}C$. But this does not give much influance on rice plant cultivation. 2. The rising of water temperature is influened according to the temperature, solar radiation but the water temperature changes according to the heat absorption of organized materials, weather and terraces. The difference of water temperature could be found in the first growing stage. 3. Through the warm water way of water rises to the temperature of $21.6^{\circ}C$ which also rises to the temperature of around $30^{\circ}C$ in the paddy field of submerged irrigation. The rice plants are comparatively free from prolonged cool damage, reproduction abstructive damage. 4. The water temperature in rice field in proportion to temperature influence of weather condition but the water temperature approaches to that of weather in the days of later growing stage and water temperature become lower than the air temperature in the fruit stage. 5. The water in the submreged field is $10^{\circ}C$ warmer than in the warm water way during the first growing stage period but the water temperature in the warm water way is warmer in the later growing stage period. The cool water of $14.5^{\circ}C$ is warmed to $30.1^{\circ}C$ and rice plants cultivation is free from other damages. 6. The 12% increased production or 570.98kg/10a is made cool water plot by rising the temperature of water from $14.5^{\circ}C$ to $21.6^{\circ}C$ making the water run through warm water way. 7. The damage inflicted by the cool water irrigation during the first growing stage period is the obstruction of peak tillering stage and the obstruction of heading the later growing stage period and the obstruction of fruiting and number of panides per fill.

• 한국농림기상학회지
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• 제4권3호
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• pp.169-174
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• 2002

When the long - lasting stationary fronts were pushed northward by the Pacific Highs in late July, mostly clear skies with intermittent showers were a typical weather of August in Korea. However, torrential rains and flash floods are now a seasonal event of August in recent years. Some meteorologists suspect this unusual phenomenon might be connected with the global change and are concerned about the possibility of change in summer climatic pattern in Korea. August of year 2002 must be remembered to be one of the record breaking months with respect to the rainfall events. In this paper, we analyzed the weather and crop data nationwide for August in 2002, and suggest a few countermeasures necessary to overcome the wet and cool summer impacts on agricultural sector.

• 한국잠사곤충학회지
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• 제36권2호
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• pp.110-114
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• 1994

93년 뽕나무 생육기에 내습한 이상저온 현상에 대한 감수정도와 요인을 분석하는 한편, 경감대책을 마련하기 위해 수원 잠업시험장과 충남 공주군에 소재한 충남도 잠업사업소 등 2개 장소에서 방임구를 대조로 요소엽면시비구 (요소 0.7%), 잠시비료 8호구 (요수 0.7%와 미량요소 함유), 그리고 질소질 6kg/10a를 황산암모늄으로 덧거름한 4개처리구를 설치하여 시험결과 다음과 같았다. 1. 여름베기후 뽕나무 생육기간 중인 6월 하순-9월 상순사이에 전국적으로 평년대비 평균기온은 1.4$^{\circ}C$ 낮았으며, 강우량은 83mm나 많았으며, 그 결과 가을뽕 수량은 평년대비 16.4% 감수되었는데, 뽕잎의 감수에 더 크게 영향하는 요인은 기온의 저하보다는 강우량의 과다에서 오는 질소질의 용탈에 원인하는 것으로 판단되었다. 2. 이상저온 내습시 생육부진을 막기 위해 요소 및 잠시비료 8호를 각각 엽면시비한 구보다는, 질소질 6kg/10a를 덧거름으로 시비한 구에서 5% 수준에서 통계적인 유의차가 인정될 정도로 증수되었다. 3. 뽕잎분석 결과 전질소 함량은 요소살포구와 질소질 덧거름구에서 방임구 3.53% 대비 0.53% 높았다.

• 대한설비공학회지:설비저널
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• 제14권2호
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• pp.125-137
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• 1985

Standard weather data for Seoul has been developed for use in computer calculations for energy requirements, and the 8760 sequential hourly values for seven weather elements have been placed in magnetic tape and cards. Applying the method determining average month, developed by Japanese Society of Heating, Air-Conditioning and Sanitary Engineers, the standard year data have been selected from the monthly average values for three weather elements during the 10year period of 1971 through 1980. The followings are obtained. 1. The Test Reference Year, consisting of 12 months chosen from different calendar years, has been determined, and TRY tape which contains seven weather elements has been prepared. 2. The Typical Weather Year, which means a year close to the average value, is the year of 1978 during the above 10 year period. 3. During the period, Winter Season needs the maximum heating load is from Dec. 1976 to Mar. 1977 and Summer Season needs the maximum cool ins load is from Jun. to Sep, 1978.

• 한국의류학회지
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• 제24권5호
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• pp.696-701
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• 2000

Stockings are considered to be excellent in retention of heat in cool weather. This study was to investigate the physiological effects of wearing support panty stocking when exposed to the cool environment from mild environment. Five healthy female college students wearing(ST) or not wearing(NST) support panty stocking, rested at 25$\pm$1$^{\circ}C$, 50$\pm$5% R.H. and were exposed to 18$\pm$1$^{\circ}C$, 50$\pm$5% R.H. for 90 minutes. The results obtained were as follows: Rectal Temperatures were lower in ST than in NST at both environments. Skin temperatures in ST were revealed higher at $25^{\circ}C$, but lower at 18$^{\circ}C$ than in NST. Heat production and total weight loss didn't show significant difference between ST and NST. Total thermal conductance from the body to the environment was higher in ST than in NST at 18$^{\circ}C$. It was suggested that wearing support panty stocking would keep the body warm in mild environment, but facilitate heat loss from the body in cool environment.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1995년도 봄 학술발표회 논문집
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• pp.154-159
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• 1995

Cold weather concrete presents the many characteristic variation of quality, according to the mixing and cooling point, the cooling time and the quantity of air besides the compressive strength of concrete. Thus, in this study to verify the character of cold-weather concrete we make the concrete specimens at laboratory and cool them at cooling-melting machine and then test the 7days compressive strength of them, with the variation of compressive strength of concrete, cooling point, cooling time, cooling weather and air quantity. At the results, the compressive strength of concrete decrease in the case of early cooling point, long cooling time, low cooling temperature and the low design compressive strength