• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2005년도 추계 학술발표회 제17권2호
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• pp.599-602
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• 2005

In this research, the characteristics of the strength development and chloride attack resistance on the concrete using high early strength cement by steam curing temperature condition were studied. As a result, It is observed that the early strength(16hr) is increasing and the strength of 28 days is decreasing, according as the rising of the steam curing temperature without the kinds of base cement(OPC and high early strength cement). On the other hand, it is observed that the more the contents of the unit binder(base cement + GGBF) is abundant, the more the steam curing temperature can be reduced in case of the high early strength. Also, the chloride attack resistance is improved according as the amount of GGBF is increased with the kinds of base cement(OPC and high early strength cement).

• Journal of Information Processing Systems
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• 제6권3호
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• pp.385-402
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• 2010

Most of the data warehouse (DW) requirements engineering approaches have not distinguished the early requirements engineering phase from the late requirements engineering phase. There are very few approaches seen in the literature that explicitly model the early & late requirements for a DW. In this paper, we propose an AGDI (Agent-Goal-Decision-Information) model to support the early and late requirements for the development of DWs. Here, the notion of agent refers to the stakeholders of the organization and the dependency among agents refers to the dependencies among stakeholders for fulfilling their organizational goals. The proposed AGDI model also supports three interrelated modeling activities namely, organization modeling, decision modeling and information modeling. Here, early requirements are modeled by performing organization modeling and decision modeling activities, whereas late requirements are modeled by performing information modeling activities. The proposed approach has been illustrated to capture the early and late requirements for the development of a university data warehouse exemplifying our model's ability of supporting its decisional goals by providing decisional information.

• 한국건축시공학회지
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• 제12권6호
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• pp.566-574
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• 2012

To address the problem of global warming, consumption of cement, the main material of concrete, should be decreased. Unfortunately, when industrial by-products are used in large quantities as admixture, the early age strength of concrete will be decreased, reducing its viability for use in concrete structures. Therefore, in this study, the application of an ionization accelerator and alkaline activator as addition agent of superplasticizer were investigated to secure a similar early age strength to that of normal concrete, thus increasing the viability of low cement concrete. Through the investigation, it was found that specimens that used a combination of Alkaline-activator (Na2Sio3) and ionization accelerator (Amine) had the highest early and long-age compressive strength. From this, we can determine an appropriate range of application of superplasticizer to improve early-age compressive strength of low cement concrete.

• 한국보육지원학회지
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• 제18권1호
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• pp.23-50
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• 2022

Objective: The purpose of this study was to develop an early childhood teacher's autonomy scale in the implementation of the Early Childhood Curriculum and to verify its validity and reliability. Methods: A literature review and a delphi survey were conducted in order to explore conceptual characteristics and develop a preliminary questionnaire. A main survey was conducted on 375 early childhood teacher to test their item quality, validity and reliability. Results: The final scale was composed of 24 items with four factors: 'support for child-centered play environment and interaction' (7 items), 'use of learning community' (4 items), 'cooperation and participation with family and local community' (6 items), and 'flexible daily management' (7 items). And the scale was verified as a stable and reliable tool. Conclusion/Implications: This is expected to contribute to the correct understanding of children's education and to actively realize the autonomy of early childhood teachers in the implementation of the Early Childhood Curriculum.

• Clinical and Experimental Pediatrics
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• 제55권11호
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• pp.414-419
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• 2012

Purpose: This study aimed to assess early development in very low birth weight (VLBW) infants with mild intraventricular hemorrhage (IVH) or those without IVH and to identify the perinatal morbidities affecting early neurodevelopmental outcome. Methods: Bayley Scales of Infant Development-II was used for assessing neurological development in 49 infants with a birth weight <1,500 g and with low grade IVH (${\leq}$grade II) or those without IVH at a corrected age of 12 months. Results: Among the 49 infants, 19 infants (38.8%) showed normal development and 14 (28.6%) showed abnormal mental and psychomotor development. Infants with abnormal mental development (n=14) were mostly male and had a longer hospitalization, a higher prevalence of patent ductus arteriosus (PDA) and bronchopulmonary dysplasia (BPD), and were under more frequent postnatal systemic steroid treatment compared with infants with normal mental development (n=35, P<0.05). Infants with abnormal psychomotor development (n=29) had a longer hospitalization and more associated PDA compared to infants with normal psychomotor development (n=20, P<0.05). Infants with abnormal mental and psychomotor development were mostly male and had a longer hospitalization and a higher prevalence of PDA and BPD compared to infants with normal mental and psychomotor development (n=19, P<0.05). Using multiple logistic regression analysis, a longer duration of hospitalization and male gender were found to be significant risk factors. Conclusion: Approximately 62% of VLBW infants with low grade IVH or those without IVH had impaired early development.

• 대한조선학회 특별논문집
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• 대한조선학회 2013년도 특별논문집
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• pp.35-41
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• 2013

Nowadays, automated modeling system for steel margin based on interactive user interface has been developed and applied to the production design stage. The system could increase design efficiency and minimize human error owing to recent CAD technique. However, there has been no approach to the pre-nesting design stage at all in early modeling process especially where ship model should be handled at more than two design stages using AVEVA Marine. A designer of the design stage needs artificial intelligence system beyond modeling automation when 3D model must be prepared in early modeling process using AVEVA Marine because they have focused on 2D nesting traditionally. In addition, they have a hard time figuring out the model prepared in previous design stage and modifying the model for steel purchase size in early modeling process. In this paper, artificial intelligence modeling system for automated application of steel margin in early modeling process using AVEVA Marine is developed in order to apply to the pre-nesting design stage that can detect effective segments before a calculation to find if a segment locates near block butt boundaries by filtering noise segments among lines, curves and surface intersections based on IT big data analysis.

• 한국수정란이식학회지
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• 제9권2호
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• pp.167-172
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• 1994

This experiment was arried out to investigate the development of ea4y rabbit embryos in vivo. Twenty-six New Zealand White does were superovulated by treatment with PMSG(Intervet Co; I. M single injection, 150. U./rabbit) followed 3 day later by simultaneous I.V injection of 100 I.U HCG (Intervet Co, )and natural service with fertile male. All of does was killed at the specific times (24, 27, 30, 36, 42, 50 and 93 h post-hCG) to find out the early embryonic development in vivo respectively. Embryos at the specified stages of development were obtained at the following times after injection of hCG; one-ceH at 24 h, two-cell at 24~27h, four-cell at 27~36 h, morulae at 50 h and early blasto-cyst at 93 h and expanded or hatching blastocyst at 144 h. Number of embryos recovered per rabbit superovulated was 26.1 and average of recovery rate was 83.7%. The results suggest that superovulation was efficient for the increase of embryo number in rabbits, and as shown in results, asynchronous cleavage was prevalent among the recovered embryos.

• Genomics & Informatics
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• 제17권3호
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• pp.24.1-24.8
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• 2019

Early environmental exposure is recognized as a key factor for long-term health based on the Developmental Origins of Health and Disease hypothesis. It considers that early-life nutrition is now being recognized as a major contributor that may permanently program change of organ structure and function toward the development of diseases, in which epigenetic mechanisms are involved. Recent researches indicate early-life environmental factors modulate the microbiome development and the microbiome might be mediate diet-epigenetic interaction. This review aims to define which nutrients involve microbiome development during the critical window of susceptibility to disease, and how microbiome modulation regulates epigenetic changes and influences human health and future prevention strategies.

• 한국산학기술학회논문지
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• 제21권10호
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• pp.386-392
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• 2020

3D 프린팅 콘크리트는 연속 적층 시 적층고가 높아짐에 따라 콘크리트의 자중이 증가되기 때문에 연속 적층성 확보를 위해 하단부 콘크리트가 적정 시간에 경화되어야 한다. 특히, 기온이 낮은 동절기의 경우 콘크리트의 경화속도가 늦어지게 되는데, 3D 프린팅 콘크리트 시공 중 하단부 콘크리트의 강도발현이 낮아 콘크리트의 자중을 버티지 못하게 되면 적층된 콘크리트가 무너지게 되는 문제가 발생된다. 이러한 문제점을 해결하기 위해서는 저온환경에서의 3D 프린팅 콘크리트의 초기강도를 증진이 필수적이다. 국내외 문헌에서는 Amine계, Nitrate계, Sodium계, Calcium계 등의 무기계 화학 첨가제를 사용하여 콘크리트의 초기강도를 증진시킨 사례가 보고되고 있다. 이에 본 연구에서는 Amine계, Nitrate계 및 Sodium계 조강형 첨가제 샘플 5종을 제작하여 그 성능을 평가하였고, 우수한 성능을 보인 샘플을 선별하여 이를 적용한 3D 프린팅 콘크리트의 초기강도 특성을 확인하였다. 그 결과 Nitrate계 첨가제 사용 시 10 ℃ 환경에서 기존 20 ℃ 환경의 3D 프린팅 콘크리트 배합대비 동등 이상의 초기강도 발현이 가능한 것을 확인할 수 있었다.

• 생명과학회지
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• 제13권1호
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• pp.34-41
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• 2003

The hatching of fertilized egg and early development of larval black seabream, Acanthopngrus schlegeli by immersion of 3,5,3'-triiodo-L-thyronine ($T_3$) with doses of 0.01~0.5 ppm in tank were examined for early development periods and compared with control fish immersed by 0.1 N NaOH and 99% alcohol. Larvae were fed with rotifers for first 5 days during experimental period. Yolk absorption of larvae from $T_3$ immersion groups were significantly faster than that of control. Although hatching times among each groups were not significant difference. the hatching rates of larvae in higher doses (0.1 ppm and 0.5 ppm $T_3$ groups) were significantly lower than control. The results of $T_3$ immersion experiments to newly hatching larvae indicated that exogenous $T_3$induced significant faster the absorption of yolk and oil globule, faster the development of myotome and digestive duct and higher the growth rate of larvae than larvae of control. These results indicate that $T_3$ immersion supplements appear to confer a distinct advantage to eggs and larvae of black seabream, which is in early fragile developmental stage.