• 한국구조물진단유지관리공학회 논문집
• /
• 제8권2호
• /
• pp.177-183
• /
• 2004

적산온도은 시멘트 수화의 결과로서 시간이 경과함에 따라 콘크리트 강도가 얻어진다는 것으로 콘크리트의 강도는 시멘트의 수화반응과 관계가 있다. 시멘트의 수화반응은 온도와 경과시간에 큰 영향을 받는다. 따라서 본 연구에서는 콘크리트 강도예측에 있어서 양생시간과 온도의 함수인 적산온도와 고강도콘크리트 강도의 상관성을 검토하고자 하였다.

• 한국철도학회:학술대회논문집
• /
• 한국철도학회 2005년도 추계학술대회 논문집
• /
• pp.21-26
• /
• 2005

The recent developments in the field of reliability and safety is the realisation that these aspects are not only a function of the product but also of the organisation realising this product. Comparing with old DIN 0801 and new method IEC61508, quantitative analysis is required at not only product's quality but also organization's level. Product's life cycle also should be evaluated by analyzing relevant or maturity of business processes. This paper shows the necessity for an analysis on all aspects in a safety certification process, and presents an overview of the available tools and techniques for the various quadrants. Especially, tools and techniques for IEC61508 quadrant C are unavailable currently. Therefore, this paper propose the method which improves the maturity of an organization on reliability management.

• 한국콘크리트학회:학술대회논문집
• /
• 한국콘크리트학회 2004년도 추계 학술발표회 제16권2호
• /
• pp.245-248
• /
• 2004

The prediction of the strength of cold weather concrete and the analysis of the insulating material effect were performed to apply the prediction function with maturity concept for quality control of them in this study. The several results driven from above processes were summarized as followings. First, the difference between the temperature of cylinder covered with insulating materials and that of cylinder without them was $4.5\~6.0^{\circ}C$. Second, the maturity of concrete was suggested to be keep higher than $96\~115^{\circ}C{\cdot}D$ until at least 7-day and the temperature of fresh concrete was suggested to be keep above $10^{\circ}C$ directly after set.

• International Journal of Computer Science & Network Security
• /
• 제21권4호
• /
• pp.223-228
• /
• 2021

As a consequence of sudden outbreak of COVID-19 pandemic worldwide, educational institutes around the globe are forced to switch from traditional learning systems to e-learning systems. This has led to a variety of technology-driven pedagogies in e-teaching as well as e-learning. In order to take the best advantage, an appropriate understanding of the cognitive capability is of prime importance. This paper presents an intelligent cognitive maturity recognition system for confidence-based e-learning. We gather the data from actual test environment by involving a number of students and academicians to act as experts. Then a Genetic Programming based simulation and modeling is applied to generate a generalized classifier in the form of a mathematical expression. The simulation is derived towards an optimal space by carefully designed fitness function and assigning a range to each of the class labels. Experimental results validate that the proposed method yields comparative and superior results which makes it feasible to be used in real world scenarios.

• 대한수학회보
• /
• 제58권2호
• /
• pp.349-364
• /
• 2021

This paper studies the optimal surrender policies for a variable annuity (VA) contract with a surrender option and a fixed insurance fee for guaranteed minimum maturity benefits (GMMB). In our proposed model, a policyholder pays the fixed insurance fee. Based on the integral transform techniques, we derive the analytic integral equations for the optimal surrender boundary and the value function of the VA contract that can be solved numerically by recursive integration method. We provide numerical values for the value function, the optimal surrender boundary, and the expected optimal surrender time.

• 한국수산과학회지
• /
• 제53권1호
• /
• pp.36-42
• /
• 2020

The maturation and spawning of white crocker Pennahia argentatus were investigated using samples collected in the Southern Sea of Korea from January to December 2018. We analysed monthly changes in maturity stage, gonad-osomatic index (GSI), total length (TL) at 50% group maturity. The spawning period was May to July. Fecundity varied between 71,627 and 888,041 eggs. The relationship between the fecundity and TL of the fish was expressd in the fecundity equation as F=0.2198TL^4.2784 (r²=0.8423). The percentage of sexually mature females estimated from a logistic function was over 50% for the size group 19.33 cm (total length, TL).

• Journal of the Korean Data and Information Science Society
• /
• 제25권3호
• /
• pp.513-522
• /
• 2014

옵션가격의 결정에 있어서 실제 변동성은 사후에 알 수 있는 정보이므로 대용값으로 내재변동성을 가장 많이 사용하는데 본 연구에서는 동일한 기초자산을 가진 옵션의 잔존만기와 행사가격을 이용하여 내재변동성을 추정하고자 한다. KOSPI200 옵션 데이터와 서포트벡터회귀, 나무모형 및 회귀모형을 통해 모형의 설명력을 평균제곱근오차 (RMSE)와 평균절대오차 (MAE)를 사용하여 살펴보았다. 그 결과 서포트벡터회귀와 MART의 성능이 최소제곱회귀보다 우수한 것으로 나타났으며, 서포트벡터회귀와 MART의 성능은 거의 비슷하였다.

• 한국작물학회지
• /
• 제50권1호
• /
• pp.11-15
• /
• 2005

This experiment was conducted to investigate the changes of growth and maturity and to clarify the function of supernodulating characters, excessive nodules and high biological nitrogen fixation rate (BNF), on maturity in response to different planting time in supernodulating soybean mutants. Two supernodulating soybean mutants, Sakukei4 and SS2-2, and their parent cultivars, Enrei and Shinpaldalkong2, were planted on May 24 and June 15, 2004. The degrees of the shortening of growth days by the planting time delay were 18 to 22 days in four cultivar, and there were no significant differences among the cultivars. However, four cultivars showed the different maturity properties. Sakukei4, mutated from Enrei, showed later maturity than that of Enrei, and 882-2, mutated from Shinpaldalkong2, showed earlier maturity than that of Shinpaldalkong2. The plant and nodule dry weights at R6 stage of Sakukei4 showed the smallest decrement and those of SS2-2 was showed the largest decrement by the delay of planting time. The photosynthetic rates of Sakukei4 during the late reproductive growth period were slowly decreased, however those of SS2-2 were steeply decreased in two planting time treatments. Overall, the growth of Sakukei4 was decreased slowly, however the growth of SS2-2 was decreased sharply according to the delay of planting time. The percentage of seed yield of Sakukei4 in June planting plot compared with May planting plot at R8 stage was $92\%$, which was the lowest decreasing rate of yield among the cultivars, and in the case of SS2-2, it was in $76\%$, the highest one. These results indicated that the responses of supernodulating mutants by the delay of planting time were very similar to the wild types. This means supernodulating characters in supernodulating soybean mutants might not affect to the maturity property. Additionally, the maturity property could be considered as an important characteristics to decide or to select on the developments of supernodulating soybean mutants, which have a low productivity by an excessive nodules, especially.

• 융합보안논문지
• /
• 제12권4호
• /
• pp.25-31
• /
• 2012

정보보호수준 검증방법은 프로세스를 중심으로 정보보호 제품, 시스템, 서비스를 개발하려는 조직의 개발능력을 평가하는 SSE-CMM(System Security Engineering-Capability Maturity Model)모델이 있다. CMM은 소프트웨어 개발업자의 개발능력을 평가하고 개선시키며 조직 전체의 성숙도 수준을 측정하는 모델이다. 그러나 이 방법은 보안엔지니어링 프로세스의 개선과 능력을 평가하는데 조직차원이 아닌 개별 프로세스의 능력수준 평가에 그치고 있다. 본 연구과제에서는 이들 기존연구를 근간으로 기술적 관점에서 정보보호수준 성숙단계를 정의하고자 한다. 연구방법은 정보보호취약점 진단, 기술보안체계 검증, 기술보안 이행실태 진단으로 구성한다. 제안하는 방법론은 업무현장에서의 범위와 수준에서 정보시스템의 현재 상태, 취약점 실태, 정보보호 기능 이행과 기능만족도 수준을 평가한다. 제안된 방법에 의한 평가결과는 정보보호 개선대책 권고모델 수립 근거로 활용하여 정보보호 개선의 활용을 목표로 하고 있다.

• 한국수산과학회지
• /
• 제53권1호
• /
• pp.67-73
• /
• 2020

The maturity and spawning of the yellow goosefish Lophius litulon were studied using samples collected monthly from January to December 2018 from the coastal waters of Korea. We analyzed monthly changes in maturity stage, gonadosomatic index (GSI), total length (TL) at 50%, 75%, and 97.5% group maturity, egg diameter and fecundity. The spawning period was from January to June. The size of eggs spawned was between 0.30 to 1.28 mm. Fecundity varied between 328,314 to 1,624,783 eggs. The percentage of sexually mature females estimated from a logistic function was over 50% at 48.67 cm TL, 75% at 56.76 cm TL and 97.5% at 74.89 cm TL.