• 한국건축시공학회:학술대회논문집
• /
• 한국건축시공학회 2021년도 가을 학술논문 발표대회
• /
• pp.131-132
• /
• 2021

According to the domestic specification, the curing of the specimen for strength management used to determine the time of the mold deformity of the structure concrete in early spring and early autumn is cured in the field structure condition. However, when the seal curing is performed in the field, the temperature of the specimen is very low compared to the temperature of the actual structure, so the strength of the structure concrete predicted based on the strength of the specimen is much undervalued than the actual one, which causes the mold to be deformed. Therefore, this study analyzed the temperature history and compressive strength characteristics of the specimen for strength management through other sealing curing at 5℃ and concrete of the actual structure, and presented the most suitable curing method.

• Asian-Australasian Journal of Animal Sciences
• /
• 제20권11호
• /
• pp.1684-1688
• /
• 2007

This study examined the caponization effects on the muscle characteristics (quality and quantity) of caponized male chickens fed before or after sexual maturity. Healthy and uniform Single Comb White Leghorn chickens were caponized at 3-week-old. Feeding was conducted until 16-week-old in trial 1 or from 12-week-old to 26-week-old in trial 2. Ten sham operated male chickens (Sham) were also assigned to each trial as the control group. Chickens used in both trials were housed in individual cages with each chicken representing one replicate. The results showed that early caponization (3-week-old) significantly increased (p<0.05) body weight and pectoral major muscle weight and percentage at 16-week-old compared to the Sham in trial 1. Caponization significantly increased (p<0.05) the protein content of the pectoral major muscle, but decreased (p<0.05) the ash content. Late caponization (12-week-old) significantly decreased (p<0.05) the ash content, myofibrillar ATPase activity and emulsification capacity of the pectoral major muscle in mature capons (26-week-old) compared to the Sham in trial 2. Early caponization (3-week-old) only increased the weight and protein content of the pectoral major muscle with decreased ash content in 16-week-old capons. Late caponization (12-week-old) showed no affects on pectoral major muscle quantity, while it decreased the ATPase activity and enhanced the emulsification capacity in mature (26-week-old) capons. Hence, the muscle quality improvement was shown as capons were fed to sexual maturity.

• Asian-Australasian Journal of Animal Sciences
• /
• 제20권1호
• /
• pp.19-24
• /
• 2007

Covariance components and genetic parameters of weekly live body weight from hatching to six weeks of age and age of sexual maturation were estimated in a laying type Japanese quail line. The univariate and bivariate animal model analysis included hatching group and sex as fixed effects. Each trait was analysed with animal as random effect to fit the additive direct effect. Additional random effects incorporated in the models were changed according to the trait examined. The best model for a trait was chosen based on a likelihood ratio test, comparing the models with and without maternal additive genetic and maternal permanent environmental effects. Heritability estimates of live-weight at hatch and one to six weeks of age with their standard errors were 0.22${\pm}$0.088, 0.39${\pm}$0.099, 0.31${\pm}$0.086, 0.38${\pm}$0.056, 0.46${\pm}$0.055, 0.50${\pm}$0.059, and 0.56${\pm}$0.062, respectively. Direct heritability value of age of sexual maturation was moderate (0.24${\pm}$0.055). The variances due to permanent environmental effect of dam after one week of age and maternal genetic effect after two weeks of age were not important sources of variation. The correlations between direct and maternal genetic effects were negative and ranged from high to moderate values (-0.21 to -0.83). Among the weekly live weights, genetic correlations were generally high between not only successive but also early and late weightings. It suggests that selection for final weight may be based on early weight records. Genetic correlations between age of sexual maturation and live weights were low, favourable but had high standard errors. These results indicate that selection for high weight will potentially result in lower age of sexual maturation only with accurate determination of breeding values.

• 복식
• /
• 제56권3호
• /
• pp.81-90
• /
• 2006

The objective of the study is to review trends of clothing export in important countries of the world and thus to know the present stage of clothing export in Korea. For the purpose, changes of export amount, competitiveness and product life cycle were analysed in the countries from the 1960's to the 1990's. The results are as following: First, on the aspect of export amount, industrialized countries lost the lead to newly industrializing countries from the 1960's. Developing countries, as China, win the lead. Second, on the competitiveness aspect, industrialized countries lost competitiveness to newly industrializing countries before the 1960's. And newly industrializing countries were outpaced by China in the export competitiveness from the early 1990's. Third, on the aspect of product life cycle, industrialized countries go first through each period of product life cycle, introduction, growth, maturity and decline, and they all, excluding Japan, sustained period of Maturity for a long time. newly industrializing countries and developing countries go orderly through each period of product life cycle after industrialized countries. As to Korea, duration of each period was short. Specially characteristics of decline period appeared partly in the early 1990's. From the results, the theory of product life cycle, helping to explain changes in production and trade in new product lines, estimated to applicable to clothing export. The phenomena, Italy, Hong Kong and America sustain high competitiveness in the world clothing market for a long time, is needed to be studied carefully. The study about strong points in their clothing industries and competitiveness drive program be to influence Korean export policy in the future.

• 대한수의학회지
• /
• 제14권1호
• /
• pp.1-7
• /
• 1974

Little work has been done on the changes in the blood picture occurring at different ages in cattle. In our country Kim (1963) and Jeong (1965) recorded the blood picture of mature Korean native cattle and, recently, Mun et al. (1974) has recorded the blood picture of Holstein cows. And a comprehensive survey of the blood picture of Korean native cattle has not been made. The object of the present investigation was to make good this deficiency, and to suggest standards for the blood picture of Korean native cattle at frequent intervals from birth to maturity. The cattle were kept under average farming conditions in this country. Observations were made at the following ages: at birth; 1, 2 and 4 days; 1, 2 and 4 weeks; 2,4,6 and 9 months; 1, 2 and 3 years of age. Blood samples were drawn from the jugular vein. Erythrocyte enumerations, concentration of hemoglobin in blood and hematocrit values were made in usual manner. Erythrocyte counts increased from $8{\times}10^6/mm^3$ during the first week to a level of $10{\times}10^6/mm^3$ at 2 months of age, showing steady state untill 6 months of age; it then fell to adult level ($8{\times}10^6/mm^3$) at 9 months of age. Concentration of hemoglobin in blood and hematocrit values were closely related to the changes of erythrocyte counts. The values increased from 10 g/100 ml and 31~35 ml/100 ml during the early life to 11 g/100 ml and 38 ml/100 ml at 2 months of age, showing steady state untill 6 months of age; these then fell to adult level (10 g/100 ml and 31~34 ml/100 ml) at 9 months of age for concentration of hemoglobin in blood and hematocrit values, respectively. Mean corpuscular volume and mean corpuscular hemoglobin showed a common pattern. The values were $42{\sim}43{\mu}m^3$ and 12.4 pg during the early life and fell a little to 6~9 months of age; these then increased to reach adult levels of $43{\mu}m^3$ and 12.6 pg for mean corpuscular volume and mean corpuscular hemoglobin, respectively. Mean corpuscular hemoglobin concentration was little affected with age.

• 한국응용곤충학회지
• /
• 제18권2호
• /
• pp.101-106
• /
• 1979

대두의 주요해충인 콩나방의 피해를 경감시키기 위해 생물학적구제책을 모색하기 위해서 재래수집종에 콩나방피해율과 형태적특성과의 관계를 검토하였다. 또 품종및 경종조건을 달리한 후 콩나방의 피해를 조사한 결과는 다음과 같다. 1474계통에 대한 콩나방피해율은 최고$38\%$에서 전혀 피해가 없는 계통까지 분포하고 평균피해율은 $5.2\%$이였다. 형태적특성으로서 협의 모용밀도 및 색과 콩나방의 피해율과는 일정한 상관성이 없으나 콩나방피해율과 maturity group 또는 진딧물피해와는 공히 $5\%$ 수준에서 정의 상관관계가 있었고 maturity group V에서 가장피해율이 높았으며 일반잎피해정도와 콩나방피해와는 부의 상관관계가 있었다. 특이한 것은 청색의 종피색을 띤 계통들에서 콩나방피해가 현저히 늘은 점이다. 파종기별 콩나방의 피해정도는 6월20일 파종구가 제일 심하여 만파구가 피해율이 현저히 높은데 이들 피해정도는 착협시기뿐만 아니라 착협에서 성숙기까지의 기간에도 관계가 있는것으로 보여진다. 재식거라에 따른 중나방피해는 소식할수록 큰 편이고 6개품종중 봉의, 충북백이 저항성인 반면 clark, 금강대립이 이충성품종으로 나타났다.

• 대한소아치과학회지
• /
• 제47권3호
• /
• pp.312-319
• /
• 2020

성조숙증은 2차 성징이 여자는 8세 이전, 남자에서는 9세 이전에 나타나는 경우를 말한다. 이 연구의 목적은 성조숙증으로 진단받은 여자 어린이들이 특별한 의과적 기왕력을 갖지 않는 여자 어린이들과 비교할 때 나타내는 치아 성숙도 특성에 관하여 분석하고자 하는 것이다. 성조숙증으로 진단받은 여자 어린이 99명과 의무기록상 특별한 의과적 기왕력을 갖지 않는 여자 어린이 99명의 파노라마 사진을 분석하였다. 하악 좌측 영구 견치, 제1, 2소구치, 제1, 2대구치의 치아 발육도를 Demirjian법을 이용하여 점수화하여 분석하여 비교하였고, 각각의 치아의 발육단계와 성조숙증 유무간의 상관관계를 분석하였다. 성조숙증군 어린이는 특별한 의과적 기왕력을 갖지 않는 대조군 어린이보다 나이가 통제된 조건 하에서 유의하게 더 진행된 치아성숙도 점수를 나타내었다(p = 0.003). 하악 제2소구치 및 하악 제2대구치의 발육단계는 성조숙증의 유무와 유의한 상관관계를 나타내었다(p = 0.000, 0.000). 모든 치아들의 발육단계를 동시에 고려한 로지스틱 회귀분석 결과에서는 하악 제2대구치의 발육단계만이 성조숙증의 유무와 유의한 상관관계를 나타내었다(p = 0.000).

• 한국초지조사료학회지
• /
• 제16권4호
• /
• pp.327-337
• /
• 1996

A field experiment was conducted at SNU Experimental Livestock Farm, Suweon in 1995 to determine effect of planting date on forage performance of wm hybrids of four different maturity groups. A split-plot design replicated three times was used, with com hybrids representing four maturity groups (115, 118, 121 and 125 days) being the main plots and planting dates (3124, 415, 415, 425, 515 and 5/15) the sub-plots. 1. Days to emergence and percent emergence from the March 24 planting were, on the average, 36 days and 58%, respectively, but those from the April 5 to May 15 planting averaged 12 days and 92%, respectively. 2. Plant and ear heights increased gradually as the dates of planting were delayed except the May 15 planting, however, percent ear was decreased as the dates of planting were delayed. There was a trend for the mean lodging percentage of the hybrids to be higher as the planting date was delayed. 3. The 115-and 118-day mediumearly maturing hybrids harvested on August 18 produced silages with a dry matter content between 27 and 30% at all planting dates except the May 15 planting, while the 121-and 125-day medium-late maturing hybrids produced silages with a dry matter wntent less than 27% regardless of any planting dates. 4. There were no significant differences in mean dry matter yield among the hybrids, but significant mean TDN yield differences were found. The 115-, 118- and 125-day hybrids had significantly higher mean TDN yield than the 121-day hybrid. There were significant differences in mean dry matter and TDN yields among the planting dates. The mean dry matter and TDN yields from the April 5, 15 and 25 plantings were significantly higher than those of other plantings, however, there were no significant differences in mean TDN yield among the April 5, April 15 and April 25 plantings. No significant planting date $\times$ maturity interactions were found for both the dry matter and TDN yields. 5. Mean stover NDF and ADF contents of the 115- and 118day hybrids were higher than those of the 121- and 125-day hybrids, but the reverse was true for mean stover IVDMD and RFV. Mean stover NDF an ADF contents increased with earlier plantings, but mean stover IVDMD and RFV increased when planting was delayed. Results of this experiment indicate that for corn planting in central and northern areas of Korea, early to mid-April may be the right time with the 115-to 118-day maturity hybrids when silage making before August 20 is taken into consideration.

• 한국수산과학회지
• /
• 제41권4호
• /
• pp.253-260
• /
• 2008

Gonadal development, gametogenesis, reproductive cycle, spawning, relative weight of flesh, and onset of sexual maturity of the murex shell, Ceratostoma rorifluum, collected from the rocky intertidal zone of Daehang-ri, Buan-gun, Jeollabuk-do, Korea were investigated monthly from January to December 2005 both cytologically and histologically. The gonads were widely placed on the digestive gland located in the posterior spiral fleshy part in the shell. C. rorifluum had separate sexes, and was an internal fertilizer. The sex ratio of females to males was approximately 1:1. The ovary and testis contained a great number of oogenic follicles and spermatogenic tubules, respectively. The oogonia and fully ripe oocytes were $15-19{\mu}m$ and $150-160{\mu}m$ in diameter, respectively, and the cytoplasm of the ripe oocytes contained a number of yolk granules. The relative weight of flesh reached a maximum in August($39.35{\pm}0.40%$), and then decreased rapidly in November($32.75{\pm}1.20%$). The percentages of female and male snails at first sexual maturity with shell heights ranging from 12.1-14.0 mm were 60.0% and 52.9%, respectively, while 100% of the snails of both sexes with shell heights over 18.1 mm were reproductively active. Based on the gonadal development and histological observations, the reproductive cycle of the snail could be categorized into five successive stages: early active(December to May), late active(March to July), ripe(June to September), spawning(July to October), and recovery(October to March). C. rorifluum spawned once a year between July and October, and the majority of spawning occurred in September when the seawater temperature exceeded $23.5^{\circ}C$.

• 한국패류학회지
• /
• 제29권4호
• /
• pp.313-323
• /
• 2013

Gonad development, the reproductive cycle, first sexual maturty and size at 50% of group sexual maturity (the biological minimum size) of Gomphina (Macridiscus) veneriformis were investigated for clams collected from the coastal waters of Donghae City, the East Sea of Korea by histological, and morphometric analysis. Monthly variations of the gonad index showed a pattern similar to that of the reproductive cycle. The reproductive cycle with the gonad developmental stages in female and male G. (M.) veneriformis can be classified into five successive stages: early active stage (December to March), late active stage (March to June), ripe stage (June to July), partially spawned stage (June to August), and spent / inactive stage (September to December). The spawning period continued from June to August, with a peak between July and August when the seawater temperature exceeds $20^{\circ}C$. The percentages of first sexual maturities of female and male clams ranging from 25.1 to 30.0 mm were 56.3% in females and 61.1% in males, and for clams over 30.1 mm shell length, it was 100%. Shell lengths at 50% of group sexual maturity (biological minimum size, $RM_{50}$) were 27.71 mm in females and 26.31 mm in males. Because harvesting clams < 26.31 mm in shell length could potentially cause a drastic reduction in recruitment, a measure indicating a prohibitory fishing size should be taken for adequate fisheries management.