• Journal of The Korean Association For Science Education
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• v.18 no.4
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• pp.601-615
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• 1998

Establishing and evaluating science education policies and revising and monitoring the effectiveness of science curriculum should be based upon the results of systematic and scientific research studies. Advanced nations have already been administering and developing national level science assessments for these purposes. The science assessments administered in Korea have been reported having many limitations and problems, and not succeeded in providing data for science education policy making and curriculum reform. The major purpose of the study is developing national level science knowledge assessment system in order to identify longitudinal trends of elementary and secondary school students science knowledge achievements. The research team consisted of science education experts and teachers from various school levels, decided the directions and major elements of national level science knowledge assessment with the consultation of educational evaluation experts. Item developing ability of the researchers was improved by seminars? and workshops on national assessment in advanced nations and developing skills of writing science items. Nearly 500 items were developed and revised. Pilot test was administered with 958 students at various school levels. 380 items were selected and tested with 8766 students, and the characteristics were analyzed in terms of item response theory. The target populations for national level science knowledge assessment are 5th-grade of elementary school, 2nd-grade of middle school, 1st and 2nd-grade of high school students. The proper period for the assessment is February every year. Multi-stage clustered sampling method is desirable and rotated forms are recommendable for the test format. Bridge items should be introduced to compare the results of multiple tests, and various grades. Anchor items should also be used for longitudinal interpretations of the results. The items for elementary school require low to medium abilities, for middle school and first grade of high school require medium to high abilities and for 2nd-grade of high school high abilities. The discrimination ability of the items developed is high.

• Biomedical Science Letters
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• v.4 no.1
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• pp.27-33
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• 1998

This study has been designed in order to examine a physiological role of $Ca^{2+}$ which has been known as an essential factor for capacitation, to confirm whether the enzyme activity of $Ca^{2+}$-ATPase on capacitation is important or not, and to clarify relationship between various levels of the $Ca^{2+}$ concentration and $Ca^{2+}$-ATPase which has been known to be an important factor of the plasma membranes. In the present study applying quercetin, a $Ca^{2+}$-ATPase inhibitor, the enzymatic effect of $Ca^{2+}$-ATPase on capacitation was found to be remarkable: a significant increase of the transition from the original type (type A) to the type B and the type AR of the spermatozoa. This finding suggests that $Ca^{2+}$-ATPase plays an important role in the efflux and the influx of the $Ca^{2+}$ which has been known to be an essential factor the capacitation and acrosome reaction, and that the inhibitory action of the $Ca^{2+}$-ATPase might be a prerequsite step toward the acrosome reaction. The conclusion reached can be deduced as follows: increment of the intracelluar $Ca^{2+}$ concentration occurred by controlling the slope of $Ca^{2+}$ concentration through $Ca^{2+}$-ATPase activities in both the intra- and extracelluar fluid may be an important procedure for capacitation and acrosome reaction, and ultimately for fertilization of the spermatozoa and the ova.

• Clinical and Experimental Reproductive Medicine
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• v.31 no.2
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• pp.119-131
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• 2004

연구 목적: 난소에서 분비되는 스테로이드 호르몬인 에스트로젠과 프로게스테론은 포유동물의 생식기관 발달과 정상적인 생식 기능, 수정과 배아의 착상에 중요한 역할을 한다. 특히 에스트로젠은 자궁내액을 내강으로 분비하여 자궁부종 기작에 중요한 역할을 한다. 자궁내액은 정자의 수정능력 획득과 착상전 배아의 발달에 매우 중요하다. Aquaporin (AQP)은 막관통 물수송 단백질로서 여러 조직에 넓게 분포되어 있으며, 세포간 또는 상피세포간 물의 이동에 중요한 역할을 한다. 본 연구에서는 생쥐 자궁에서 스테로이드 호르몬에 의해 조절되는 자궁내액의 이동에 AQP 유전자가 관여하는지를 알아보았다. 연구 재료 및 방법: 난소 절제술을 시행한 생쥐에 스테로이드 호르몬을 피하주사하고 6, 12, 24시간 간격으로 자궁조직을 적출하였다. 대조군은 sesame oil만을 주사한 후 6시간째에 수획한 자궁조직을 사용하였으며, 실험군은 시간대별과 스테로이드 처리별로 채취한 자궁조직에서 역전사중합효소반응을 수행하였다. 역전사중합효소반응을 통해 막관통 단백질인 AQP-4, -5, -8 mRNA의 발현양상을 살펴보았다. 또한 mRNA의 위치를 살펴보기 위해 laser microdissection을 이용하여 RT-PCR을 수행하였다. 마지막으로 자궁조직내에서의 단백질 발현 부위를 관찰하기 위해 면역조직화학염색을 실시하였다. 결 과: AQP-4, -5, -8 mRNA은 프로게스테론을 처리한 군보다 에스트로젠을 처리한 군에서 많이 발현되었으며, 에스트로젠을 주사한 지 6시간째 발현정도를 대조군과 비교할 때 AQP-4, -5, -8 mRNA가 각각 7.9배, 2.8배, 3.8배로 나타났다. AQP-4, -5, -8 mRNA는 간충조직보다 자궁내 상피조직에서 스테로이드 호르몬의 영향을 받아 발현양상의 차이가 나타났으며, 주로 에스트로젠의 영향을 받아 발현이 증가하였다. AQP-4 단백질은 에스트로젠을 24시간 처리한 후 프로게스테론을 처리한 군의 자궁내 상피조직에서 많이 발현되었으며, AQP-5와 -8 단백질은 에스트로젠을 처리한 군의 자궁내 상피조직에서 발현이 증가하였다. 결 론: 이상의 결과를 통해 AQP-4, -5, -8은 주로 에스트로젠에 의해 자궁내 상피세포에서 발현이 증가되는 것으로 보아 에스트로젠의 영향하에 일어나는 자궁내액의 이동으로 인한 자궁부종기작에 이동통로로서 관여하는 것으로 사료된다.

• Korean Journal of Animal Reproduction
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• v.23 no.1
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• pp.13-18
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• 1999

The totipotential spermatogonial stem cells of adult testis which give rise to mature sperm cells is well-known to incorporate foreign DNA as well as those of somatic cells. Also, the integration rates of foreign DNA after haploid stages are generally known to decrease and /or is simply bound foreign DNA into the sperm plasma membrane. To overcome these problems, liposome and DNA complexes were used to determine how direct injection of these complexes into testis were integrated into sperm genome and resulted in transgenic offspring. To study this purpose, cation liposome was gently mixed with WAF/hGH DNA (1 : 2) and the complexes were injected into testis. At 10, 20, 40, 60, and 80 days after direct injection into testis, mature sperm cells were recovered by using artificial virgin method from two goats and each semen except a part of semen used for DNA analysis such as PCR or Southern blotting was cryopreserved for the artificial insemination. The results obtained in this study are summarized as follows. 1. By PCR, the presence of exogenous DNA was confirmed up to 80 days after injection with liposome/DNA complexes. The highest integration rates were obtained at day 40 after direct injection. This results suggested that spermatogonial stem cells were integrated exogenous DNA into their genome. 2. Among 23 Korean Native Goats which were artificially inseminated, 4 goats resulted in pregnancy and produced 7 young goats. 3. Two young goats were confirmed as a transgenic by PCR and Southern blot analysis. Therefore, our results suggested that testis-mediated gene transfer can be used as a feasible tools for the production of transgenic livestock.

• Journal of The Korean Association For Science Education
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• v.32 no.1
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• pp.95-112
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• 2012

The research evaluated the effects of the improvements in scientific inquiry for elementary school students and focused on the development and application of the explicit and reflective learning strategy through observation and classification. The explicit and reflective learning strategy was modified and completed with the review of the experts after the development of the draft based on the theoretical approach. The students were evaluated for their academic achievements in scientific inquiry skills before and after taking the course. The results were as follows: First, the steps of the developed learning strategy (1) to motivate, (2) to explore reflectively, (3) to guide explicitly, (4) to inquire explicitly, and (5) to verify reflectively were set to reflect the verification. Second, the results of applying the developed model to the lessons based on the quantitative analysis was effective for observation and classification skills in the quest for improved performance of the whole (the sum of observation and classification, inquiry skills) and the observed features, but there was no effect on classification. Also, the lessons applied the developed teaching strategy and showed effectiveness in improving academic achievement. Particularly in analyzing the relationship between the academic achievement and exploration capabilities, in order to improve academic achievement, the importance of improving inquiry skills was found. Third, the qualitative analysis of teaching and learning strategy developed by applying the lessons of this teacher guide and small group activities through the explicit and reflective observation and classification of the student learning activities showed the significant improvement of ability of the scientific inquiry skills. In addition to the improvement in the abilities of the classification showed after the formation of the most basic observation skills of the scientific inquiry.

• The Journal of Korean society of community based occupational therapy
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• v.2 no.1
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• pp.75-84
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• 2012

Objective : This study aims to identify the effect of an occupational therapeutic intervention program including horticultural therapy on cognition and daily living performance of the elderly with dementia. Methods : For the purpose, the study measured the changes before and after the therapy, targeting sixteen women with dementia who were living in nursery facilities. We used MMSE-K to analyse the cognition, and evaluated daily living performance using K-MBI(p<.05). Results : The results of the study were presented as follows: 1. To identify changes of MMSE-K before and after the therapy between the control and test groups. As a result, it was discovered that MMSE-K of the control group was $16.25{\pm}1.38$ before the therapy and $16.00{\pm}.92$ after the therapy, which indicated no significant differences, but MMSE-K of the test group was $16.00{\pm}1.51$ before the therapy and $17.87{\pm}1.35$ after the therapy, which was statistically significant (p<.05). 2. To identify changes in daily living performance(K-MBI) between the two groups before and after the therapy, and it was discovered that scores of the control group were $74.00{\pm}1.30$ before the therapy and $74.25{\pm}1.16$ after the therapy, which showed no significant difference, but those of the test group were $73.75{\pm}1.28$ before the therapy and $76.37{\pm}1.30$ after the therapy, which was statistically significant(p<.05). Conclusion : Based on the results above, it was demonstrated that the an occupational therapeutic intervention program including horticultural therapy had a positive effect on cognition and daily living performance of elderly women with dementia and it is suggested that the results can be used as basic data for clinical intervention of the elderly with dementia.

• Proceedings of the Korean Information Science Society Conference
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• 2012.06a
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• pp.98-100
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• 2012

모바일 웜의 전파 속도는 시간이 지날수록 급격히 빨라진다. 급속도로 전파하는 웜을 억제하기 위한 연구가 계속 진행되어 왔다. 기존 연구 중 하나로 소셜 네트워크를 그래프(Graph)로 표현하고 분할한 뒤 각 파티션의 대표노드(Key Node)를 선택해 웜 패치를 전파하는 기법이 있다. 이 기법은 패치 전파 속도를 웜 전파 속도보다 빠르게 해서 웜을 억제 시킨다. 하지만 이 기법에서는 대표노드에 가중치(Weight)가 낮은 간선(Edge)이 연결 될 수 있거나 대표노드가 없는 파티션이 생길 수 있다. 잘못된 대표노드 선정은 패치 전파속도를 저하시키고 웜 억제를 지연시킬 수 있다. 본 논문에서는 페이지랭크를 이용해서 대표노드를 선정하는 개선된 소셜 네트워크 기반의 웜 패칭 기법을 제안한다. 제안 기법은 웜 패칭 전략에 사용할 수 있도록 수정한 페이지랭크를 각 파티션에 적용해서 대표노드를 선정한다. 파티션마다 전파 능력이 가장 높은 노드가 대표노드로 선정되기 때문에 웜 패치 전파 속도를 향상시킬 수 있다.

• Journal of the Korean Society of Marine Environment & Safety
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• v.18 no.6
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• pp.563-568
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• 2012

In 2010 the Manila Amendments established the highest practicable standards for officers and engineers. This amendments includes knowledge, understanding, skills, and proficiency required for a deck officer in terms of the BRM (Bridge Resource Management) to reduce human errors, stated in the International Convention on Standards of Training, Cerification and Watchkeeping for Seafarers (STCW). This paper proposes a proper direction to improve BRM education program in Korea. In relation to the BRM program, its contents and education method were analyzed through the satisfactions survey for cadets and the experienced officers. As a consequence, this research gives several suggestions to improve the current BRM course.

• Journal of The Korean Association of Information Education
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• v.7 no.1
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• pp.48-56
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• 2003

In this study, I have developed a template system for development of educational homepages. So teachers can easily maintain and repair it. This system consists of a information management system that manages the information of members and a school, a template management system that is consisted of interfaces by the template files that are informations and ASP codes, a menu management system that easily make and modify system menus for user. As results of applying the developed system, it improved the utilization of school homepage. This system will improve the teachers's and student's ICT utilization ability and contribute to our country's education information policy.

• KDI Journal of Economic Policy
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• v.22 no.1_2
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• pp.3-55
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• 2000

본 연구는 세입증가율 예측을 위해 사용되는 각종 세수추계모형의 예측능력을 상호비교하는 데 목적이 있다. 본 연구에서 고려하는 세수추계 방식은 네 가지이다. 첫째는 단순 ECM 모형으로서 오차수정모형(error correction model)을 각각의 세목에 적용하여 세수를 예측하는 것이다. 둘째는 SUR-ECM 모형으로서 단순 ECM 모형의 개별 회귀방정식을 통합하여 SUR(Seemingly Unrelated Regression) 방식으로 추정한 후 이를 이용하여 세수를 예측하는 것이다. 셋째와 넷째는 흔히 사용되는 탄성치 방식으로서, 과거의 연도별 탄성치를 5년간 또는 10년간 평균하여 이를 바탕으로 향후의 세수를 예측하는 것이다. 이러한 모형비교를 통해 얻은 결과는 다음과 같이 요약될 수 있다. 첫째, 단순 ECM 모형과 5년 평균 탄성치 모형은 예측력에 있어 큰 차이가 없다. 둘째, SUR-ECM 모형과 10년 평균 탄성치 모형은 예측력에 있어 큰 차이가 없다. 셋째, 단순 ECM 모형보다는 SUR-ECM 모형의 예측력이 높으며, 5년 평균 탄성치 모형보다는 10년 평균 탄성치 모형의 예측력이 높다. 넷째, 어느 경우에든 예측 오차가 상당히 크고 이러한 오차는 예측시계가 넓어질수록 커진다. 예를 들어, 5년 후의 세수에 대한 예측치는 평균적으로 오차의 절대값이 10% 수준에 이른다. 탄성치 모형이 단순 ECM 모형이나 SUR-ECM 모형에 비해 그리 나쁜 예측결과를 낳지 않는다는 것은 새로운 사실이다. 또한 5년 평균 탄성치보다 10년 평균 탄성치를 사용하는 것이 더 나은 예측치를 낳는다는 것은 세수예측에 있어 최근의 자료만을 사용하는 것보다는 과거 꽤 오랜 기간의 자료를 사용하는 것이 바람직하다는 점을 시사한다.