• Korean Journal of Ichthyology
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• v.23 no.1
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• pp.75-79
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• 2011

This study was conducted to investigate protocol standardization for cryopreservation spermatozoa of the bar-tailed flathead Platycephalus indicus. The suitability of the cryoprotectants, dimethyl sulphoxide (DMSO), glycerol and methanol were tested against three freezing rates and three thawing temperatures. DMSO and glycerol gave significantly higher motile index and survival rates than methanol. Among the freezing rates, freezing at a height of 2 cm above $LN_2$ surface for $10\;min^{-1}$ gave higher motile index and survival rates. In terms of best thawing temperature, $20^{\circ}C$ obtained the highest motility.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2010.04a
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• pp.196-196
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• 2010

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2005.05a
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• pp.119-121
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• 2005

• 전기의세계
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• v.20 no.6
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• pp.44-49
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• 1971

본고에서는 영국의 원자력계획의 가능규모와 이를 위한 경제적 배려의 점에서 원자력에 대한 전망을 고찰하고 다음에 모든 것이 순조로우면 1980년대 후기에 가서 발전설비계획을 석권한 초속로계통을 예로들어 연구개발, 발전소건설, 연료공급을 포함한 전반적인 산업양태에 대하여 검토한다.

• Proceedings of the Korean Nuclear Society Conference
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• 1997.05b
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• pp.463-468
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• 1997

우리나라 원전이 위치하고 있는 해안지역에서 빈번히 발생하는 해륙풍 둥과 같은 국지순환을 고려할 수 있는 삼차원 라그랑지 입자확산모델을 개발하였다. 개발된 모델을 이용하여 월성원전 부지를 대상으로 봄철 약한 북풍이 부는 밝은 날에 대해 방사성 물질의 대기확산을 모델링하였다. 모델링 결과를 통해 해륙풍에 의한 방사성 입자의 시ㆍ공간적 분포와 일주기적 확산 양태를 규명하고, 해륙풍의 풍향변화에 의한 방사성 입자의 재순환의 중요성을 확인하였다.

• Journal of The Korean Association For Science Education
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• v.29 no.1
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• pp.116-136
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• 2009

Since there are differences in the content, structure and functions of interpersonal communication during the practice of school science classes, it needs to articulate the difference of the modality of pedagogical practice in order to understand science teaching in detail. These characteristics of science teaching can be investigated by further insightful analysis on language in the science classroom. In this study, classroom discourse language codes using Bernstein's code theory were analyzed in the case of a middle school science class on the unit of minerals. The discourse language code was identified by the value of classification, which revealed power relations to the contexts of discourse and participants of discourse. It was also identified by the value of framing, which showed hierarchical relation between teacher and students as discourse subjects, and discursive control on the initiative of discourse. The results addressed that six types of discourse language codes were constructed and that those language codes reflected diverse modalities of science teaching from student-centered instruction to teacher-centered instruction in relation to classroom discourse. The modality of science teaching according to the transition tendencies of discourse language code showed dynamic variations of 'controlled student-centeredness inducing teaching' - 'positional student-centeredness permissive teaching' - 'controlled students' participation permissive teaching' - 'controlled student-centeredness facilitative teaching' - 'student-centeredness enhancing teaching'. In addition, results released that discursively and hierarchically weak control of discourse is necessary for enhancing student-centeredness of science teaching. Moreover, teaching practice enhancing student-centeredness can be accomplished by the harmony of a teacher's perception of discourse language code and his/her orientation to constructivist teaching and student-centered teaching.

• Journal of Educational Research in Mathematics
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• v.23 no.4
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• pp.517-531
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• 2013

In this study, from the viewpoint that there should be no inconsistencies in stating the learning-content achievement standards of elementary mathematics curriculum, non-consistent use of the verb 'understand', 'know' and the noun 'meaning' which are used very frequently in the learning -content achievement standards of the Korean 2011 elementary mathematics curriculum are discussed. To this end, the modes that appear inconsistently in the 2011 curriculum, the 1997 curriculum, and the 2006 curriculum are investigated and analyzed. The result is that it is difficult to see that the verb 'understand', 'know' and the noun 'meaning' in the 2011 curriculum are used on the base of some principles. Based on this result, the following three suggestions are presented as the conclusions for the development of the future curriculum. First, it is necessary to restrict the contexts in which the verb 'understand' is used in stating the learning-content achievement standards. Second, it is necessary to clarify the difference between the verb 'know' and the verb 'understand'. Third, when 'the meaning of ~ ' is used, it is necessary to clarify what the meaning implies.

• Journal of the korean academy of Pediatric Dentistry
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• v.26 no.2
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• pp.275-283
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• 1999

Authors evaluated 152 patients at the department of Pediatric Dentistry in Seoul National University Hospital through clinical records and radiographs. And the following features were studied ; age, sex distribution, number of mesiodens per patients, location, status of eruption, shape and orientation of crown, and complication. From the above results, the relationship between features of mesiodens and complications were evaluated using chi-square analysis. 1. Complications due to the presence of mesiodens did not occur in 31.6%, delayed eruption of adjacent teeth was observed in 33.6%, midline diastema in 22.4%, rotation in 8.6%, displacement in 3.3%, and crowding in 0.7% of all evaluated patients. 2. As compared with the above 8.5 year group, in the under 8.5 year group, the frequency of complications was significantly higher(P<0.05). As compared with those positioned lingually, in mesiodens labially or within the arch the frequency of complications was significantly higher(P<0.01). Also, the frequency of complications was significantly higher when the mesiodens was tuberculate in form(P<0.05). 3. Of the 104 patients with complications, the frequency of delayed eruption was significant higher in the under 8.5 year group, and in above 8.5 year group, the frequency of malocclusion was significantly higher(P<0.05). When mesiodens were located in the midline region, the frequency of malocclusion was significant higher, while in case with laterally positioned mesiodens the frequency of delayed eruption was significantly higher(P<0.01).

• Journal of the Korean Society for Precision Engineering
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• v.17 no.7
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• pp.170-180
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• 2000

In this paper, to evaluate ease of exchange of subassembly considering module, it needs to analyze structure and function of subassembly, assembly and disassembly process. Exchange process of module can be divided into pre-process and in-process, and determination factors of exchange process are defined by analyzing characteristics of assembly and disassembly process. Based on the analysis of characteristics for structure and function of subassembly, influential factors of module can be proposed. Considered the interrelationship between determination factors of ease of exchange and influencing factors of module, ease of exchange can be evaluated.

• Proceedings of the Korean Nuclear Society Conference
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• 1996.11b
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• pp.611-616
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• 1996

원자력 발전소에서 대기중으로 방출된 방사성 물질의 이동 양태는 지형과 기상조건에 의해 크게 좌우되므로, 해안가에 위치해 있는 월성부지의 경우는 빈번히 발생하는 해륙풍 특성을 규명하여 이에 적합한 환경영향평가 및 비상대응체제를 구축해야 한다. 월성부지의 해륙풍 순환구조를 파악하기 위해 봄철 해륙풍 상층기상 특별관측을 월성부지를 중심으로 4개 지점에서 실시하였다. 관측결과를 분석하여 해륙풍이 방사성 물질의 대기확산에 미치는 영향을 분석하고, 해륙풍을 반영할 수 있는 새로운 환경영향평가 방법론을 고찰하였다.