• Asian-Australasian Journal of Animal Sciences
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• 제5권3호
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• pp.449-454
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• 1992

Eight healthy Holstein bulls, 4-6 years old were used to study the effect of season of the year on the incidence of the morphologically abnormal spermatozoa. Semen was collected twice a week by A. V. over one-year period. The percentage of total abnormal spermatozoa was $14.1{\pm}0.5$. Ejaculates collected during hot summer season had significantly higher incidence of abnormal spermatozoa than those collected during winter time. Warm spring had moderate semen abnormality. In addition to its effect on the total number of morphologically abnormal spermatozoa, season affected significantly the primary as well as the secondary types of abnormalities. The differences between incidence of primary and secondary types of abnormalities were not significant for all seasons and seasons pooled together. The ratio between the total forms of abnormality in the head, mid-piece and tail of spermatozoa was as 1:1.5:1. Head and mid-piece had defected more during summer compared with both winter and spring. There was no variation in tail abnormalities due to season. The significant effect of season on head was observed by large, pyriform, free and detached heads, while that on mid-piece was by swollen, coiled mid-pieces and protoplasmic droplets.

• 소성∙가공
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• 제16권7호
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• pp.555-560
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• 2007

This paper shows some achievements at bending of extruded aluminum profiles during the extrusion process. The conventional process for the production of bent profiles involves a successive extrusion, stretching, and bending of the profiles. Conventional bending methods can not meet demands far precision and cost-effective production in some cases, due to cross sectional deformation, irregular decrease of tube wall thickness and a complication of the process design. An estimation of spring-back required for precision of the bending radius can not always be achieved by the over bending of the profile. Since the profile is hot during the bending process, the spring-back phenomenon can be avoided. This means that an additional bending process is not necessary. Consequently, flexible bending can be achieved with cost reduction and quality improvement. Experimental tests were completed to study the relationship between curvature radius of profile and position of guide on the extrusion for vehicle bumper. A7108 is applied as a billet material in order to increase strength. The overall correlation between the experimental and numerical results is good. It is therefore concluded that the present method provides an efficient means for the constant curvature extrusion process.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2016년도 추계 학술논문 발표대회
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• pp.132-133
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• 2016

This research team has developed single silk white bubble sheets to be used as surface sheath curing material for spring, summer, and autumn. But though its effects for spring and autumn temperature conditions have been proved, there haven't been any studies for summer temperature conditions. Therefore in this study, single silk white bubble sheets and single silk transparent bubble sheets as well as aluminum metalizing single silk bubble sheets have been applied to actual box-frame apartment slabs in construction, in order to compare temperature backgrounds of the concrete and other qualities. Upon application, the temperature of concrete cured in summer temperature conditions showed excellent scores, being the lowest for aluminum metalizing single silk white bubble sheets, then single silk transparent bubble sheets. But the aluminum metalizing single silk bubble sheet gave off a harmful glare, so for actual use, white single silk bubble sheets are recommended.

• Asian-Australasian Journal of Animal Sciences
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• 제26권1호
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• pp.43-49
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• 2013

The aim of this study was to compare both the performance of litters derived from two sire genetic origins (SGO), Vienna Blue (VB) and Burgundy Fawn (BF), along successive seasons of birth (SB; winter, spring, summer and autumn), and doe reproductive performance in an organic production system. A total of fifty-eight does consisting of a mixture of crosses of several medium-large size breeds at different parity order (P, 1 = nulliparous; 2 = primiparous; ${\geq}3$ = multiparous) and twelve males (6 VB and 6 BF) were housed indoors at environmental conditions that followed seasonality. An extensive reproductive rhythm was used and kits were weaned at $46{\pm}6$ d of age. Doe reproductive performance and the data of 105 litters (55 from VB and 50 from BF SGO) were recorded throughout the SB. No statistically significant differences related to SGO effect were observed. As regards parity order, multiparous does showed higher live weights (LW) (p<0.05), total born (p<0.01), total born alive (p<0.05) per delivery, and litter weight of born alive (p<0.05), but lower milk output at 21st d than primiparous does (p<0.05). The extensive reproductive rhythm mainly increased litter performance at birth in multiparous does but was not sufficient to permit a complete recovery of body reserves lost during lactation. Autumn SB negatively affected doe LW variation between deliveries. The number of pups born and born alive per delivery (p<0.05) and litter size at 21 d of age and at weaning (p<0.01) were lower during hot SB. Due to the lower litter size of pups born in summer and autumn, their individual weight at 21st d of age and daily individual growth rate 0 to 21 d were higher than those of pups born in winter (p<0.001). Litter performance at 21st d of age and individual pup pre-weaning growth rate were poorer for those born in spring than in other seasons due to the harmful effects of increased environmental temperatures. SB affected most of the performance traits of does and young rabbits reared under the organic farming system. The rabbits seemed better suited to organic rearing conditions during winter than in other seasons. The worst results overall were obtained in the spring SB, whereas the hot SB negatively affected both doe energy balance and prolificacy. In conclusion, the pups of the 2 SGO showed good pre-weaning performance and seemed suited to the organic rabbit production system.

• 한국조경학회지
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• 제44권5호
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• pp.47-58
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• 2016

이 연구는 지금까지 논의하지 않았던 근대 부산에서 벚꽃 명소의 실상을 밝히기 위하여 당시 부산에서 발간된 일간지 <부산일보(釜山日報)>와 <조선시보(朝鮮時報)>에 게재된 벚꽃 구경과 벚꽃 놀이의 기사를 발굴하여 그 장소를 토지 이용의 유형별로 분류하고, 벚꽃 구경에서 벚꽃 놀이로 변환하는 시기의 동정과 장소적 특성을 고찰하였다. 근대 부산에서 벚꽃의 명소에 관련한 신문기사는 봄의 도래를 알리는 계절화로서 벚꽃이 피어 있는 장소를 알리는 내용에서 점차 벚꽃이 군생하고 있는 장소에 모여드는 사람들의 유흥 행위를 소개하는 것으로 변화되어 간다. 단순히 벚꽃이 화려하게 피어 있는 장소는 신문지상에서 노출되는 빈도는 점점 적어지고, 벚꽃이 만개한 행락지에서 유흥 내용의 소개로 변화해 갔다. 이것은 근대 부산에서 벚꽃의 명소는 벚꽃 구경의 명소에서 벚꽃놀이의 명소로 성숙해갔다는 것을 의미한다. 첫째, 근대 부산의 벚꽃의 명소는 개인주택정원, 온천 여관의 정원, 사찰, 수원지, 배수지, 학교 등 공공용지, 동래온천장, 미도리마치 유곽 등 상점가로 나눌 수 있었다. 장소는 정주 환경의 가장자리, 다시 말해서 도시와 자연의 접점공간에 형성되었다. 둘째, 근대 부산의 벚꽃 명소는 1920년 무렵부터 벚꽃 구경에서 벚꽃 놀이로 변환되었다. 벚꽃의 명소가 성립한 것은 1920년 무렵으로 볼 수 있다. 그리고 벚꽃 구경의 명소가 개인 주택 정원, 배수지 등 공공의 접근의 어려운 곳도 거론되었지만, 벚꽃놀이의 명소는 누구나가 접근할 수 있는 공공의 장소가 주로 거론되었다. 벚꽃의 명소가 봄철 행락지가 되었다.

• 한국식품영양과학회지
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• 제36권7호
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• pp.932-937
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• 2007

양상추의 계절별(봄, 여름, 가을) 품질 차이 여부를 알아보기 위하여 일반성분, 색차, 클로로필, vitamin C 및 조직감을 측정하였으며 또한 양상추의 위해요소를 알아보기 위하여 48종의 잔류 농약을 측정하였다. 가식부 중량은 여름(953.40 g)>봄(912.27 g)>가을(895.28 g)에 수확한 양상추 순으로 나타났지만 당도는 봄에 수거한 시료가 가장 높게 측정되었다. 전체적인 색은 여름 양상추가 가장 밝은 색을 나타내었고, 다른 계절과 비교하여 가을 양상추는 노란 빛이 뚜렷하고 녹색 빛은 적은 것으로 나타났다. 무기질 함량은 가을에 수거된 시료에 가장 많이 함유되어 있었으며 또한 계절에 관계 없이 전체적으로는 칼륨 함량이 다른 무기성분에 비해 전체적으로 높게 측정되었다. 시료의 항산화능을 유추할 수 있는 chlorophyll과 vitamin C는 봄, 가을에 수거한 시료가 여름에 수거한 시료보다 높게 측정되어 전반적으로 여름에 수거한 양상추가 중량은 크지만 품질 면에서는 약간 떨어진 것으로 판단되어진다. 또한 계절별 양상추에서 검출되어진 잔류 농약은 chlorthalonil이었지만 그 양은 매우 미미하다고 판단되어진다.

• 한국환경과학회지
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• 제22권9호
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• pp.1181-1186
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• 2013

Due to climate change, the occurrence of abnormal weather conditions has become more frequent, causing damage to vegetable crops grown in Korea. Hot pepper, Chinese cabbage and radish, the three most popular vegetables in Korea, are produced more in the field than in the greenhouse. It has been a trend that the time for field transplanting of seedlings is getting earlier and earlier as the spring temperatures keep rising. Seedlings transplanted too early in the spring take a longer time to resume the normal growth, because they are exposed to suboptimal temperature conditions. This study examined the influence of air temperature during seedling growth on the time required to reach the first fruit maturity and yield of hot pepper. Seedling plants of 'Super Manita' hot pepper was grown in temperatures $2.5^{\circ}C$ and $5.0^{\circ}C$ lower than the optimum temperature (determined by the average of temperatures for the past 5 years). Seedlings were transplanted into round plastic containers (30-cm diam., 45-cm height) and were placed in growth chambers in which the ambient temperature was controlled under natural sunlight. The growth of seedlings under lowered temperatures was reduced compared to the control. The mineral (K, Mg, P, N) concentrations in the leaf tissues were higher when plants were grown with the ambient temperature $2.5^{\circ}C$ lower than the optimum, regardless of changes in other growth parameters. Tissue calcium (Ca) concentration was the highest in the plants grown with optimum temperature. The carbohydrate to nitrogen (C/N) ratio, which was the highest (18.3) in the plants grown with optimum temperature, decreased concomitantly as the ambient temperature was lowered $2.5^{\circ}C$ and $5.0^{\circ}C$. The yield of the early harvested fruits was also reduced as the ambient temperature became lower. The first fruit harvest date for the plants grown with optimum temperature (June 27) was 13 days and 40 days, respectively, earlier than that in plants grown with $2.5^{\circ}C$ (July 10) and $5.0^{\circ}C$ (Aug 6) lower ambient temperatures. The fruit yield per plant for the optimum temperature (724 g) was the greatest compared to those grown with $2.5^{\circ}C$ (446 g) and $5.0^{\circ}C$ (236 g) lower temperatures. The result of this study suggests that the growers should be cautioned not to transplant their hot pepper seedlings too early into the field, since it may delay the time of first harvest eventually reducing total fruit yield.

• 한국자동차공학회논문집
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• 제13권3호
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• pp.17-23
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• 2005

In this study, the high strength and superior toughness spring steels as the suspension material, used for automobile and railroad industries were utilized to carry out the following investigations. Corrosion times were controlled in 7, 14,30 and 60days to examine the relation between corrosion pit and compressive residual stress in the static corrosion environment after shot peened. And then corrosion current and corrosion potential were measured for every 24 hours to investigate the corrosion mechanism. Shot peened material shows the low or rate of corrosion current as compared with unpeened material. In case of hot peened material which has the highest residual stress, it has a low corrosion current density.

• 한국수학교육학회지시리즈D:수학교육연구
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• 제19권4호
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• pp.211-227
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• 2015

Information Technology influenced on classroom to change the teaching and learning method. Recently, flipped learning method became a hot issue in education by using Information Technology. Learning management system that is introduced in our university in the spring semester 2015, made it possible to apply flipped learning method. So, we used the flipped learning method in a calculus course. In this paper, we found that flipped learning in Calculus we was a little bit affirmative in the aspect of motivation and active learning from students' response on flipped learning method. We analyzed the reason that students were not so positive in continuing flipped learning even though they liked flipped learning a little bit better than traditional learning. We suggest what we pay attention to for applying the flipped learning method effectively.

• 환경영향평가
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• 제4권2호
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• pp.29-37
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• 1995

The national park should be preserved in accordance with the regulation, but the development planning or facilities management planning has not been faithful to the spirits of the regulation. Recently natural environment has been radically changed, and especially damaged by large scale development of Service Facilities Zone. Thus the effective land use planning of the national park is required. Therefore, the purpose of this study is to propose the alternative site for The Second Service Facilities Zone in Mt. Kyeryong National Park using the GIS, and to compare the alternative site with the existing development site. Site selection was based on Rules of Combination which covers topographic analysis, viewshod analysis, distance analysis from hot spring well, land use analysis, and forest stand analysis.