• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2005년도 추계 학술논문 발표대회
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• pp.25-28
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• 2005

This study investigates the field application of surface insulation curing method, which combined double layer bubble sheet(DBS) and thick-curing-material(TCM) for cold weather concreting. According to the test, deck slab, curing only upper section with DBS and TCM, does not make big different temperature history with that, curing both upper and bottom section during daily average temperature 6.5t. It is concluded that combination of DBS and TCM in only upper section can be safely cured in early period of time during cold water concreting. The field test was carried out with this favourable data. The upper deck slab was insulated by combination of DBS and TCM, and the construction was surrounded by tent. in order to protect from outside wind. The test result shows that the lowest temperature of deck slab indicated 6$ ^{circ}C $. It demonstrated that this curing method can resist early frost and save construction cost in the side of management and saving labor cost, compared with previous method. In addition, the column specimen, combined both form and bubble board, exhibited favorable temperature history, due to internal hydration heat insulation effect.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2003년도 학술.기술논문발표회
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• pp.19-22
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• 2003

The purpose of this study is to analyze the curing effect of planar surface heater for concreting in cold weather. Some experiments were conducted to evaluate the temperature history of concrete structures cured with heating sheets. Results are as follows ; (1) The temperature of concrete showed continuously rising trend with the heating by planar surface heater under the cold environmental condition of 3~-12$^{\circ}C$. And after about 24 hours the maximum temperature of concrete was reached at 25~3$0^{\circ}C$. (2) The temperature of slab concrete heated by planar surface heater of 130W/$m^2$ was at least $25^{\circ}C$ higher than that of an exterior air, and the curing performance was much more effective than heating by hot wind machine. (3) Through the curing by planar surface heater for 48 hours, the concrete maturity of about 1.5 times to heating by hot wind machine was acquired.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1999년도 학회창립 10주년 기념 1999년도 가을 학술발표회 논문집
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• pp.763-766
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• 1999

The objective of this study was to investigate the influence of low temperature curing on resistance of freezing and thawing of self-compacting concrete placed in cold weather regions. The experimental study results indicated that the self-compacting concrete incorporating ground granulated blast-furnace slag showed good resistance to freezing and thawing, and the self-compacting concrete cellulose viscous agent had relatively poor resistance to freezing and thawing.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1994년도 봄 학술발표회 논문집
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• pp.260-265
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• 1994

High strength concrete(65MPa) was used for construction of the bulk cement storage silo by using sliding form. This paper presents mix design, production, quality control and experience with field application of high strength concrete under cold weather conditions. It is shown to be possible to produce high strength concrete of compressive strength of 50~60 MPa by using high-range water reducer to lower w/c ratio with appropriate quality control.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2013년도 춘계 학술논문 발표대회
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• pp.67-68
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• 2013

In this paper, the compressive strength of an insulating gang form member, which was developed to improve the cold weather concreting quality, and a general gang form member was measured by age to examine the compressive strength characteristics of the two members compared with the standard curing test piece.

• 한국환경과학회지
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• 제26권10호
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• pp.1155-1166
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• 2017

This study selected commonly known species of fruit trees, and re-selected the species that endure the stress of extreme cold weather and physiologically restore themselves to the previous state until the following year. Then we could go ahead to propose the species that were appropriate as urban greening plants in weather condition of any part of the country. To do this, we conducted an experiments for six species of fruit trees based on the preference of the general public and recommendation of the experts; Morus alba (English name: mulberries), Diospyros kaki (English name: Persimmon), Prunus persia (English name: Peach), Elaeagnus umbellata var. coreana (English name: Korean Autumn Olive), Malus domestica 'Alps Otome' (English name: Alps Otome), and Prunus mume (English name: Blue Plum). The experiment verifies whether the trees survive without any stress from the cold weather under the national climate conditions (one in the suburbs of Seoul: Yongin city, one in the central Chungcheong region: Daejeon city, and in the southern Gyeongsang region: Jinju city in Korea). The experiment lasted for a year from August 2016 to August 2017. The levels of electrolytic efflux, chlorophyll content, plant height, fresh weight, and dry weight were measured four times (on August of 2016, January, February, and August of 2017) for each tree planted bare ground outdoors. Results showed that Diospyros kaki, Prunus persia, and Malus domestica 'Alps Otome' were proven durable and resistant to winters of all three areas (one in the suburbs of Seoul: Yongin city, one in the central Chungcheong region: Daejeon city, and in the southern Gyeongsang region: Jinju city in Korea). Especially, the increase of chlorophyll content and the reduction of electrolytic efflux were noticeable in Prunus persia than in the other two species, proving itself as the most cold-tolerant among the six species used in the experiment. In addition, interpreting from the physiological restoration data of one-year span before and after getting through winterer, Prunus persia was proven to be the most cold-tolerant species.

• The Korean Journal of Pain
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• 제34권1호
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• pp.66-71
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• 2021

Background: Trigeminal neuralgia is a debilitating craniofacial pain syndrome that is characterized by paroxysms of intense, short-lived electric shock-like pains in the trigeminal nerve distribution. Recently, the presence of triggers has become one of the key diagnostic criteria in the 3rd edition of the International Classification of Headache Disorders. Light touch is the most common trigger, however other non-mechanical triggers, such as cold weather and certain foods, have been thought to provoke trigeminal neuralgia anecdotally. We aimed to characterize the prevalence and characteristics of these atypical triggers. Methods: We conducted a retrospective, cross-sectional study of atypical triggers in trigeminal neuralgia patients seen in a tertiary pain clinic in Singapore. Patients were recruited via clinic records, and study data were identified from physician documentation. Results: A total of 60 patients met the inclusion criteria. Weather triggers were observed in 12 patients (20%), of which five patients (8%) reported strong winds, 4 patients (7%) reported cold temperatures, and 3 patients (5%) reported cold winds as triggers. Fifteen patients (25%) had a specific food trigger, of which 10 patients (17%) reported hard or tough food, 5 patients (8%) reported hot/cold food, 4 patients (7%) reported spicy food, and 2 patients (3%) reported sweet food as triggers. Conclusions: Although trigeminal neuralgia is most commonly triggered by mechanical stimuli, atypical triggers such as cold temperatures and certain foods are seen in a significant proportion of patients. These atypical triggers may share a common pathway of sensory afferent Aδ fiber activation.

• 대기
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• 제26권1호
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• pp.193-201
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• 2016

An anomalous cold-weather period occurred during January 2011 in East Asia, and this study investigates the event by focusing on the blocking phenomena formed at Northeastern Asia. The area of cold weather is determined to represent the characteristic features of abnormal cold temperature. The 2010/11 winter is divided into three periods P1, P2 (cold period), and P3. For the cold area ($30-50^{\circ}N$, $115-135^{\circ}E$) the corresponding cold period P2 is determined to be 39 days from 23 December 2010 through 30 January 2011. During P1 and P3 temperature anomalies from the climatological mean are small with large standard deviation compared to those of P2, which has large negative anomaly and small standard deviation. The period P2 is dominated by blocking, which was determined by distributions of 500-hPa geopotential height and potential temperature on the 2 PVU surface. Correlation-coefficient analyses show that during P2 the temperature in the cold area is related with pressure of Northeastern Asia, while the temperature during P1 and P3 is related with pressure of Northwest of Korea. Also, during P1 and P3 the temperature pattern shows eastward propagation, but during P2, a stationary pattern. All the observations imply that, during the cold period P2, the temperature in the cold area is related with blocking in Northeastern Asia. During P1 and P3 temperature pattern is related with 500-hPa geopotential height in Siberia, and this relationship is also observed in the climatological mean state.

• 한국환경과학회지
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• 제28권9호
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• pp.765-784
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• 2019

The synoptic structural characteristics associated with heavy snowfall (Bukgangneung: 31.3 cm) that occurred in the Yeongdong area on 20 January 2017 was investigated using surface and upper-level weather charts, European Centre for Medium-Range Weather Forecasts (ECMWF) reanalysis data, radiosonde data, and Moderate Resolution Imaging Spectroradiometer (MODIS) cloud product. The cold dome and warm trough of approximately 500 hPa appeared with tropopause folding. As a result, cold and dry air penetrated into the middle and upper levels. At this time, the enhanced cyclonic potential vorticity caused strong baroclinicity, resulting in the sudden development of low pressure at the surface. Under the synoptic structure, localized heavy snowfall occurred in the Yeongdong area within a short time. These results can be confirmed from the vertical analysis of radiosonde data and the characteristics of the MODIS cloud product.

• 한국환경과학회지
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• 제31권12호
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• pp.1069-1078
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• 2022

This study investigated the weather conditions, fine particle concentration, and ion components in PM_2.5 when two cold fronts passed through Busan in succession on February 1 and 2, 2021. A analysis of the surface weather chart, AWS, and backward trajectory revealed that the first cold front passed through the Busan at 0900 LST on February 1, 2021, with the second cold front arriving at 0100 LST on February 2, 2021. According to the PM₁₀ concentration of the KMA, the timing of the cold front passage had a close relationship with the occurrence of the highest concentration of fine particles. The transport time of the cold front from Baengnyeongdo to Mt. Gudeok was approximately 11 hours . The PM₁₀ and PM_2.5 concentrations in Busan started to increase after the first cold front had passed, and the maximum concentration occurred two hours after the second cold front passed. The SO₄^2-, NO₃^-, and NH₄⁺ concentration in PM_2.5 started to increase from 1100 to 1200 LST on February 1, after the first cold front passed, and peaked at 0100 LST to 0300 LST on February 2. However, the highest Ca²⁺ concentration was recorded 2-3 hours after the second cold front had passed.