• 한국패류학회지
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• 제21권2호
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• pp.81-93
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• 2005

Reproductive cycle with the gonadal phases, first sexual maturity, artificial spawning amount by the size and spawning interval of the hard clam, Meretrix lusoria were investigated by histological observations and morphometric data by artificial spawning induction. Meretrix lusoria is dioecious and oviparous. The reproductive cycle of this species can be classified into five successive stages: early active stage (January to March), late active stage (February to May), ripe stage (April to August), partially spawned stage (June to September), and spent/inactive stage (September to February). The spawning period was from June to September, and the main spawning occurred between July and August when the seawater temperature exceeds over $20^{\circ}C$. Percentage of first sexual maturity of female and male clams ranging from 40.0 to 45.0 mm in shell length was over 50%, and all clams over 50.0 mm in shell length sexually matured. Female and male clams ranging from 40.0 to 45.0 mm in shell length are considered to be two years old. Therefore, we assume that the hard clams of both sexes begin reproduction from two years of age. The mean number of the spawned eggs increased with the increase of size (shell length) classes. In case of artificial spawning induction, the number of spawned eggs from the clams of a sized class was gradually decreased with the increase of the number of the spawning frequencies (the first, second, and third spawnings). In the experiments of artificial spawning induction during the spawning season, the interval of each spawning was estimated to be 15-18 days (average 17 days).

• 한국패류학회지
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• 제21권2호
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• pp.95-105
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• 2005

Gonadosomatic index, reproductive cycle, spermatogenesis and first sexual maturity of Chlamys farreri were investigated by cytological and histological observations, from January 1998 to December 1999. The gonadosomatic index (GSI) rapidly increased in April and reached a maximum in May when seawater temperature rapidly increase. Then the GSI gradually decreased from June to August when spawning occur. Accordingly, monthly changes in the GSI in males coincide with the reproductive cycle. The spermatozoon of Chlamys farreri is the primitive type found in external fertilization species. The head of the spermatozoon is approximately $2.75{\mu}m$ in length including the acrosome measuring about $0.50{\mu}m$ in length, and its tail was approximately $20{\mu}m$, the axoneme of the tail flagellum consists of nine pairs of microtubules at the periphery and a pair at the center. Five spherical mitochondria around the centriole (the satellite body) appear in the middle piece of the sperm. The spawning period was from June to August and the main spawning occurs from July to August when seawater temperatures are greater than $20^{\circ}C$ The reproductive cycle of this species can be categorized into five successive stages; early active stage (January to March), late active stage (March to April), ripe stage (April to August), partially spawned stage (June to August), and spent/inactive stage (August to January). Over 50% of male scallops attained first sexual maturity between 50.0 and 60.0 mm in shell height, and 100% of those over 60.0 mm in shell height achieved maturity. Accordingly, we assume that male individuals begin reproduction at three years of age.

• 대한치과교정학회지
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• 제28권3호
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• pp.409-417
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• 1998

경희의료원 치과병원 교정과에 내원한 부정교합자 중 전신 건강 상태가 양호한 123명의 좌측 수완부골 방사선 사진을 이용하여, 초경과 골격성숙도간의 상관관계를 연구한 결과 다음과 같은 결론을 얻었다. 1. 초경 발현 연령은 평균 12.31세, 최소 9.6세, 최고 15.6세로 개체간 변이가 심하였다. 2. 초경시 골성숙 상태는 SMI 7,8단계($73\%$), 즉 제5중절골의 골단이 골간을 둘러싸거나 제3말절골의 골간과 골단이 융합되는 단계이며, 초경시의 골격성숙도는 초경 발현 연령에 관계없이 일정하였다. 3. 골성숙단계에 따른 초경 후 경과기간간에는 유의한 차이가 있었다. 4. 요골의 융합은 초경 후 평균 1년 8개월이 지나면 시작되었다. 5.초경 발현 연령에 따른 성장 속도의 비교에서, 만기성숙아(초경을 늦게 경험하는 여아)는 초경 후 14개월이 지나면 요골의 융합이 시작되었고, 조기성숙아(초경을 일찍 경험하는 여아)는 초경후 22개월, 평균성숙아는 초경후 20개월이 지나면 요골의 융합이 시작되었다.

• 한국작물학회지
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• 제49권5호
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• pp.373-380
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• 2004

The production of sweet (su) and super sweet corns (sh2) has been economically feasible in Korea in recent years. Major factors limiting super sweet corn production are low germination and low seedling vigor. Since seed quality is closely related to seed maturity, the optimum harvest time for the seed production of sweet and super sweet corns was studied and the quality of seeds with varying maturities was investigated in 2001 and 2002 cropping seasons. The parents of the sweet corn seeds were Hybrid Early Sunglow and 'Golden Cross Bantam 70' and those of super sweet corn were Xtrasweet 82 and 'For­tune'. Seeds were harvested at 21, 28, 35, 42, 49, and 56 days after silking (DAS). As the seeds developed, seed weight of sweet corn increased and the seed moisture content decreased faster than that of super sweet corn. Germination rates of sweet corn seeds harvested 21 and 28 DAS at $25^{\circ}C$ and emergence rates in the cold soil test were significantly lower than those of seeds harvested after 42 DAS in both years. Although the germination rates of super sweet corn seeds with varying maturities showed similar patterns as sweet corn seeds at $25^{\circ}C$, the emergence rate of super sweet corn seeds in cold soil test continuously increased with seed maturity. This suggests that seed quality of super sweet corn should be tested in a cold soil test to estimate field emergence. As the seeds developed, leakage of total sugars and electrolytes from the both sweet and super sweet corn seeds decreased up to 42 or 49 DAS. The $\alpha-amylase$ activities of both sweet and super sweet corn seeds increased with seed maturity from 21 to 35 or 49 DAS depending on genotype and year. The optimum harvest time for the seed production of sweet corn was 42 DAS and 49 DAS for super sweet corn considering emergence rate and plumule dry weight in the cold soil test, leakage of sugars and electrolytes from the seeds, and $\alpha-amylase$ activity.

• 한국국방경영분석학회지
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• 제33권2호
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• pp.49-60
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• 2007

최근 임베디드 소프트웨어는 유 무선 통신의 발전 및 디지털 정보기기의 확장, 그리고 이러한 기기들의 컨버전스 등을 통해 그 활용 분야가 급격히 확장되고 있으며 그 기능이나 품질에서도 더욱 완전한 소프트웨어를 개발하려는 노력이 강조되고 있다. 이에 따라 소프트웨어 결함을 조기에 발견하여 임베디드 소프트웨어의 품질을 향상시키려는 소프트웨어 테스트 프로세스에 대한 중요성이 더욱 부각되었으나 고도의 정확성과 실시간 처리가 요구되는 임베디드 소프트웨어에 적용할 수 있는 테스트 프로세스 모델은 없는 실정이다. 따라서 본 논문에서는 임베디드 소프트웨어의 특징과 테스트 프로세스의 특성을 반영한 임베디드 소프트웨어 테스트 성숙도 모델(Emb-TMM) 설계를 위한 절차와 사례연구 결과를 제시한다. 이를 위해 Emb-TMM 설계절차를 참조모델 선정 및 영역 도출, 수준별 영역 분류 그리고 모델 설계라는 세 가지의 큰 부분으로 분류하여 제안한다. 그런 다음 제안한 Emb-TMM 설계절차를 통해 실제로 임베디드 소프트웨어 개발 시 어떻게 적용할 수 있는지를 사례연구를 통해 제시한다.

• 인터넷정보학회논문지
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• 제8권2호
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• pp.15-22
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• 2007

결함을 초기 단계에 발견하여 제거함으로써 품질이 좋은 소프트웨어를 만들 수 있다 이를 위해 결함을 효과적으로 추적하고 관리하는 결함 추적 시스템(Defect Trucking System)의 도입이 필요하다. 기존의 결함 추적 시스템은 한꺼번에 많은 종류의 데이터를 모음으로써 이를 도입한 조직에서 수많은 데이터를 왜 모아야 하는지에 대해 인식이 부족하고 결함 관리프로세스 없이 도구만 적용함으로써 결함 추적 시스템 도입에 어려움을 겪고 있다. 또한 CMMI 성숙도 수준 2, 3에서는 결함 관리 활동을 수행하는 프로세스 영역이 없기 때문에 CMMI 성숙도 수준 2, 3에 해당하는 조직이 결함 추적 시스템을 도입하는데 문제가 되고 있다. 이에 본 논문에서는 CMMI 기반의 조직이 기존의 결함 추적 시스템을 도입하였을 때 생기는 문제점을 해결하고 CMMI 각 성숙도마다 어떤 결함 데이터를 모아야 하는지, 어떻게 결함 관리를 해야 하는지에 대한 가이드라인을 제공하고자 한다. 그리고 검토 및 테스팅을 통해 도출된 결함 데이터에 대하여 각 담당자 별로 업무를 할당, 추적할 수 있게 하며, 결함에 관한 각종 상태정보와 통계 정보 등을 제공하는 결함 분석 및 통제 시스템을 개발하고자 한다.

• 원예과학기술지
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• 제30권4호
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• pp.400-408
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• 2012

Effects of initial controlled atmosphere (CA) treatment on quality maintenance of 'Fuji' apples were assessed and compared with 1-methylcyclopropene (1-MCP) treatment and continuous CA storage. Apples were harvested twice at different maturity, treated with 1 ${\mu}L{\cdot}L^{-1}$ 1-MCP and then stored for 8 months at $0^{\circ}C$ under 3 conditions: air, CA for the first month followed by air (initial CA), and continuous CA (full CA). CA storage was performed with 1.5 kPa $O_2$ and < 1.0 kPa ($N_2$ balance). Following long-term storage, export simulation, refrigerated shipment and local distribution, were performed by holding apples at $0^{\circ}C$ for 2 weeks and on the shelf at $20^{\circ}C$ for 7 days. Both the application of 1-MCP and CA storage reduced ethylene production and respiration rates. Initial CA storage was also effective on reducing the metabolism although the effects were not as noticeable as full CA. Full CA storage with or without 1-MCP treatment maintained titratable acidity, flesh firmness, and sensory quality at the acceptable to excellent level even after the export simulation following 8-month storage regardless of harvest maturity. In contrast, effects of initial CA storage were limited to the maintenance of firmness and texture in early-harvested apples. Overall results indicated that harvest maturity is the critical factor for export fruit quality after long-term storage when separate treatment of initial CA storage or 1-MCP treatment is applied as a postharvest program.

• Journal of Plant Biology
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• 제17권1호
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• pp.15-21
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• 1974

The most commonly grown economical and flue-cured tobacco cultivar Yellow Special A was used in pot-culture tests in order to study Ethrel (2-chloroethyl phosponic acid) effects on accelerating maturity of tobacco leaves in relation to the most adequate level of the chemical useful for field growing, nitrogen level in soil for the most pronounced response, and the most suitable spray period during the growth stages of pre-, post- and topping periods. The following conclusions, thus, were obtained from the present studies; 1. 500ppm Ethrel spray was reconfirmed to be adequate in the practical applications, although the extent of yellow-ripening of tobacco leaves was increased as the Ethrel level increased. The highest leevel treated resulted in causing chemically damaged lesions on leaves and early defoliation. 2. Ethrel-treated leaves showed deeper yellowish tinge to them than those without treatment, while different levels of the chemcial had less influence on the tinge. 3. An adequate level of nitrogen supply to plants favored the Ethrel response, whereas either very low or high level of nitrogen in the soil lowered the chemical effect on accelerating the yellow-ripening. When carbohydrates versus total nitrogen ratio became relatively high, the condition brought out some outstanding Ethrel effects. 4. Chlorophyll level of leaves increased as soil applications of nitrogen level increased, and that also increased carotenoid level of the tobacco leaves. Ethrel-treated leaves showed deeper orange tinge than those without treatment, while the highest level of nitrogen application showed the deepest orange tinge to tobacco leaves. 5. Pre-topping treatment (12 days before topping and flowering) resulted in almost no Ethrel response, and that treatment right on the day of topping, showed response of yellow-leaf ripening at nearly bottom-half leaves of a tobacco plant. The post-topping treatment (12 days after topping) made plants showing full response of Ethrel from bottom to the top leaves of tobacco plant in accelerating the leaf maturity. 6. The extent of Ethrel responses on accelerating yellow-ripening of tobacco leaves was discussed for the modifying influences brought about by certain environmental factors. Discussions were also made about the possible practical applications (particularly for pre-rice planting) and quality difference that may be caused by such growth environments.

• 한국구조물진단유지관리공학회 논문집
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• 제18권6호
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• pp.82-89
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• 2014

이 연구의 목적은 다양한 혼화재의 치환과 양생온도를 고려한 콘크리트의 압축강도 발현을 평가할 수 있는 단순모델의 제시이다. 이를 위해 ACI 209의 포물선 식을 성숙도 함수를 기반으로 하여 수정하였으며, 압축강도 발현 상수 A, B 그리고 재령 28일 압축강도는 264개의 기존 실험결과들의 회귀분석으로부터 결정하였다. 제시된 모델의 검증을 위하여 혼화재 치환과 양생온도를 변수로 3그룹의 실험을 수행하였다. 콘크리트의 28일 압축강도는 양생온도가 표준양생온도(20도시)보다 높을수록 또는 낮을수록 감소하였다. 초기 재령3일동안 표준온도에서 양생을 한 콘크리트의 압축강도 발현은 그 이후 양생온도 변화에 영향을 거의 받지 않았다. 제안된 모델의 예측값과 실험값의 비의 평균과 표준편차는 각각 1.00와 0.08로서 실험결과와 잘 일치하였다.

• 한국어류학회지
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• 제21권2호
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• pp.93-99
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• 2009

본 연구는 전남바다목장 해역 내에 서식하는 감성돔의 성숙과 산란에 관한 연구로, 2007년 3월부터 2008년 2월까지 낚시어업에 의해 어획된 시료를 대상으로 수행하였다. 감성돔의 50% 성전환 체장은 26.7 cm로 추정되었고, 암컷의 생식소 발달과정 및 생식소중량지수(GSI) 월변화로부터 감성돔의 산란기는 3~7월, 주 산란기는 5~6월로 추정되었다. 포란수는 최소 39,596립(체장 32.2 cm)에서 최대 2,894,913립(체장 42.0 cm)으로 계수되었고, 체장(FL)과 포란수(F)간의 관계식은 $F=1.264FL^{3.869}(R^2=0.736)$으로, 일반적 경골어류에서와 같이 체장이 커질수록 포란수도 증가하는 경향을 보였다. 산란에 참여하는 50% 군성숙도 체장은 암컷은 25.8 cm, 수컷은 19.0 cm이다.