• Advances in concrete construction
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• 제15권6호
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• pp.359-376
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• 2023

Ultra-high-performance concrete (UHPC) has become an attractive cast-in-place repairing material for existing engineering structures. The present study aims to investigate age-dependent high-early-strength UHPC (HESUHPC) material properties (i.e., compressive strength, elastic modulus, flexural strength, and tensile strength) as well as interfacial shear properties of HESUHPC-normal strength concrete (NSC) composites cured at different season temperatures (i.e., summer, autumn, and winter). The typical temperatures were kept for at least seven days in different seasons from weather forecasting to guarantee an approximately consistent curing and testing condition (i.e., temperature and relative humidity) for specimens at different ages. The HESUHPC material properties are tested through standardized testing methods, and the interfacial bond performance is tested through a bi-surface shear testing method. The test results quantify the positive development of HESUHPC material properties at the early age, and the increasing amplitude decreases from summer to winter. Three-day mechanical properties in winter (with the lowest curing temperature) still gain more than 60% of the 28-day mechanical properties, and the impact of season temperatures becomes small at the later age. The HESUHPC shrinkage mainly occurs at the early age, and the final shrinkage value is not significant. The HESUHPC-NSC interface exhibits sound shear performance, the interface in most specimens does not fail, and most interfacial shear strengths are higher than the NSC-NSC composite. The HESUHPC-NSC composites at the shear failure do not exhibit a large relative slip and present a significant brittleness at the failure. The typical failures are characterized by thin-layer NSC debonding near the interface, and NSC pure shear failure. Two load-slip development patterns, and two types of main crack location are identified for the HESUHPC-NSC composites tested in different ages and seasons. In addition, shear capacity of the HESUHPC-NSC composite develops rapidly at the early age, and the increasing amplitude decreases as the season temperature decreases. This study will promote the HESUHPC application in practical engineering as a cast-in-place repairing material subjected to different natural environments.

• 한국축산시설환경학회지
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• 제17권2호
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• pp.107-114
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• 2011

본 연구는 계절과 성 분리가 생산성, 스트레스, 도체품질 및 육질에 미치는 영향을 분석하기 위하여 여름과 겨울로 계절을 나누고 각 계절별 암컷구, 거세 수컷구 및 혼합구를 설정하고 평균체중 $82.1{\pm}0.82kg$인 삼원교잡$(LY{\times}D)$ 비육돈 270두를 공시하여 비육돈 생산성과 출하 과정의 스트레스 및 도체품질과 육질을 분석하였다. 사료섭취량은 겨울에 많았고 증체 또한 겨울에 우수하였다 (p<0.05). 성 분리는 사료요구율에 영향을 미치며, 겨울과 혼합구가 양호한 것으로 나타났다 (p<0.05). 상차 후 혈중 cortisol과 CPK치가 급격하게 상승하는 것으로 나타나 상차시 극도의 스트레스가 주어지는 것으로 나타났다. 상차시 급격한 상승을 보였던 혈중 cortisol과 CPK 농도는 수송과정에 낮아지며, 3시간 계류 후에는 출하 전 수준으로 안정되었다. 상차 후 계절 관계없이 혼합구가 가장 높은 cortisol 농도를 보여 돈 방내에서의 수준을 유지하는 경향을 나타내었고 거세 수컷 혹은 암컷만으로 구성된 돈 군간에는 차이가 없었다. 도체품질은 겨울에 우수하였고 PSE 발생율 또한 겨울이 낮아지는 경향을 보였다. 여름철 거세 수컷구가 가장 높은 PSE 발생율을 나타내었으나 겨울철 혼합구는 가장 낮게 나타났다 (p<0.05). 계절과 성 분리가 돼지고기의 pH, drip loss 및 육색 등 육질에는 영향을 미치지 않았다. 이상의 결과를 요약하면 여름철에 비육돈 관리 특히 출하취급에 보다 세심한 배려가 필요하며, 성 분리는 관리자, 시설 등 농장여건에 따라 적용 여부를 결정하는 것이 타당할 것으로 판단된다.

• 설비공학논문집
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• 제5권4호
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• pp.278-284
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• 1993

A simplified TAC method was developed for the selection of design temperature and absolute humidity for peak cooling and heating load calculation with ETD method. And the design data of the 11 major cities in Korea were obtained. Based on the simplified TAC method, the design data for summer and autumn cooling season were selected by the TAC 5.0% of July through August and TAC 5.0% of October, respectively. But the design data for winter heating season were selected by the conventional TAC 2.5% of the full winter season.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2014년도 춘계 학술논문 발표대회
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• pp.216-217
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• 2014

Optimum finishing position, thickness and phase change temperature of winter and summer season were selected and suitability of finishing materials was evaluated based on temperature measurement of specimens applying the coating material mixed phase change materials(PCM). As a result, when finishing position was interior and finishing thickness of coating material mixed n-Octadecane(28℃ PCM) was 4mm, thermal performance was effective. n-Octadecane in summer season and n-Hexadecane(18℃ PCM) in winter season are indicated effective on energy savings, respectively.

• 한국환경보건학회지
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• 제15권1호
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• pp.75-79
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• 1989

This study was carried out to investigate water quality of mineral water located in Nam san. 8 sites were pointed out by ramdom sampling and tested for 12 items in May and December 1988. The results were as follows: 1. The range of pH value in all sites was 5.4 - 6.8. 2. NH$_{3}$-N concentrations were suitable for drinking water criteria in winter season but site 1 was not for drinking water criteria. 3. NO$_{3}$-N concentrations were suitable for drinking water criteria in all samples. 4. Most of heavy metals were detected small amount, and espically zinc were detected much amount in all sites (0.01-0.32). 5. Coliform was not detected in all sites .in summer season but site 4 and 8 were detected in winter season.

• Asian-Australasian Journal of Animal Sciences
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• 제15권3호
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• pp.382-389
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• 2002

The aims of this study is to evaluate the effect of Aspergillus oryzae Fermentation Extract (AFE) on the performance of lactating cows in summer (May to July) and winter (December to February). The experiment was a completely randomized design (CRD) and dietary treatments were 1) basal diet without AFE, 2) basal plus 3 g/d AFE into the basal total mixed ration (TMR), 3) basal plus 45.4 mg AFE/kg the ensiling corn silage and 4) AFE inclusion in silage and TMR. Twenty-eight cows from each trial were selected and randomly allocated into the four treatment groups, confined in individual pens, and fed ad libitum for 8 weeks in both seasons of feeding trials. Results showed that AFE inclusion in corn silage significantly improved DM intake by 4.4% and milk yield by 3.1% (p<0.05) during summer. In the winter season, AFE inclusion in the diet significantly improved milk yield by 10%. Direct addition of AFE to the TMR even further significantly improved milk yield over the addition through corn silage by 7.4% in winter (p<0.05). An additive effect of AFE inclusion into TMR and through corn silage was also demonstrated in the winter-feeding. AFE inclusion however, did not improve DM intake during the winter trial. In the summer trial, inclusion of AFE showed an adverse effect on the percentage of milk fat, but did not impact on the milk fat yield. Adding AFE through corn silage showed a trend towards alleviating the negative effects of milk fat from direct AFE inclusion in TMR. The similar trend occurred in the winter trial. The inclusion of AFE through corn silage significantly lowered the milk protein content over direct AFE addition, but did not significantly impacted the milk protein yield in summer. AFE supplementation during the winter season significantly increased milk protein content. Adding AFE to the corn silage significantly increased milk protein content over direct AFE addition in winter although inclusion of AFE significantly decreased total milk solid content in the summer (p<0.005). During the winter season, inclusion of AFE required less DM to produce a unit of milk. Inclusion of AFE into corn silage required less DM, energy and protein to produce a unit of milk. But inclusion of AFE did not alleviate heat stress on the lactating cows.

• 한국패류학회지
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• 제32권4호
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• pp.269-277
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• 2016

본 연구는 2015년 우리나라 서해안에서 양식된 3배체 굴의 일반성분, 지방산, 아미노산 조성 및 글리코겐 함량의 계절적 변화를 조사하였다. 지방 함량은 겨울철에 가장 높았으며 (2월, $2.10{\pm}0.06%$), 단백질 함량은 가을철에 (11월, $9.09{\pm}0.04%$) 에서 가장 높았고 수분과 회분은 여름철 (8월, $86.00{\pm}0.12%$ 및 $2.67{\pm}0.03%$) 에 가장 높았다. 총아미노산 함량은 겨울철 (1,011.5 mg/100 g) 에 가장 높았고, 점차적으로 감소하여 여름철에 가장 낮았다 (486.7 mg/100 g). 아미노산조성은 taurine, aspartic acid, glutamic acid, glycine 및 alanine 등이 주요 아미노산으로 분석되었다. 지방산 조성에서 전체 지방산 함량의 50 % 이상을 차지하는 지방산은 EPA와 DHA로 확인되었다. 글리코겐 함유량은 여름철에 가장 높았으며 ($1.26{\pm}0.03g/100g$), 다른 시기에는 $0.69{\pm}0.04-0.86{\pm}0.01g/100g$의 범위로 일정한 함량을 보였다. 이상의 결과를 종합해 볼 때, 3배체 굴은 불임처리를 통해 산란을 하지 않아 여름철에 글리코겐 함량이 높아 겨울철뿐만 아니라 여름철에도 상업적 가치가 높은 것으로 확인되었다.

• 환경생물
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• 제23권2호
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• pp.206-213
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• 2005

본 연구는 환경요인의 변화, 특히 겨울철 저온이 식물체에 미치는 영향을 정량적으로 밝히기 위해, 저온감수성 식물인 문주란을 대상으로 겨울철 일주기에 있어서 항산화효소 활성과 O-J-I-P곡선의 변화를 조사하였다. 겨울철의 superoxide dismutase와 peroxidase의 활성은 여름철에 비해 다소 증가하였다. 특히, peroxidase는 겨울철 새벽과 밤에 높은 활성을 보였으며 초겨울에만 특이적으로 검출되는 isoenzyme들로 관찰할 수 있었다. 또한 겨울철 문주란 잎의 O-J-I-P곡선에서 J, I, P-단계의 형광세기가 여름철에 비해 현저하게 감소하였다. 그리고, O-J-I-P곡선으로부터 산출된 주요 형광변수들 중에 Fm과 $\Phi_{po}$는 겨울철 저온에 노출되는 기간이 길어짐에 따라 각각 $30\%$와 $50\%$로 감소하였으며, ABS/RC는 초겨울보다는 늦은 겨울에 2배정도 증가하였다.

• 한국산림과학회지
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• 제99권2호
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• pp.226-234
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• 2010

This study was conducted to examine the effects of pruning season on the compartmentalization of pruning wounds in Acer palmatum and Pinus strobus. A total of eighty five field-grown trees for each species were allocated to five different seasons, early- and late-winter, mid-spring, mid- and late-summer, for pruning treatments. Wound closure rate (WCR) of the two species for one year after treatment, area of discolored stem tissue on the medial longitudinal surface and cambial dieback length under the pruning wound of A. palmatum were measured. Changes of total phenols and variations of extractives, holocellulose and lignin at the treated branch unions were examined. In WCR of A. palmatum, late-winter (March, 39.8%) and mid-spring (May, 39.7%) were higher than any other seasons, while early-winter (November, 28.4%) was significantly lower than late-winter and mid-spring. P. strobus showed similar results with A. palmatum. The WCR of early-winter (57.2%) was the lowest significantly among the five seasons, and mid-spring (73.5%) and late-winter (71.4%) showed higher a WCR than other seasons. In the discolored/wound area ratio of A. palmatum, early-winter (73.2%) was the highest by far, and mid- (July) and latesummer (September, 36.7%, respectively) were the lowest among the five seasons. In the length of cambial dieback, two dormant seasons, early- and late-winter were longer than any other seasons. Phenol contents at the treated branch union were changed in line with the seasonal fluctuation of the tree. Total phenols in the below core of the treated union were higher than those of the branch union with living branch, while little differences were seen in the above core. At the branch core of the treated union, phenols of A. palmatum decreased one month after the treatments, but P. strobus maintained similar to or a little higher than those at the controls. The major changes in chemical composition at pruning wounds were extractives and lignin increased by less than 20% in A. palmatum, while extractives in P. strobus remarkably increased by 70%.

• 동굴
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• 제8호
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• pp.55-64
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• 1998

Many of the familiar roadside signs advertising caves open to the public carry the phrase, “Come underground and cool off”. This is reasonable advice, for during the heat of summer the temperature of these caves is indeed pleasantly cool. If the principal tourist season were in the winter instead of the summer, however, the signs would probably read, “Come underground and warm up”, for in winter these same caves are far warmer than the surface. Cave temperatures are nearly constant throughout the year.