• Korean Journal of Culture and Social Issue
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• v.11 no.2
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• pp.1-29
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• 2005

This research examined the effect of social anxiety on psychological adaptation. Higher the social anxiety, higher in neurotism & worry but lower in Psychological Well-Being and Satisfaction with Life. Among the sub-factors of social anxiety, negative adaptation was significantly predicted by personal anxiety. However positive adaption were predicted by personal anxiety, fairness anxiety and future anxiety. Among the sub-dimensions of social anxiety, negative and positive adaptation were significantly predicted only by anticipatory anxiety. And there were significant positive correlations between social anxiety and aggressive/give-up response. Particularly, personal anxiety was the predictor of aggressive response, but safe anxiety and political anxiety were the predictors of give-up response. The dimension predicted the aggressive/give-up response was anticipatory anxiety dimension. Finally, respondents used problem solving stress coping strategy most. But the respondents whose social anxiety level especially safe anxiety and political anxiety were high used wishful thinking strategy. Moreover higher the reactive anxiety level, more frequently used the avoidance coping strategy.

• Journal of the Korean Society of Propulsion Engineers
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• v.14 no.2
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• pp.71-79
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• 2010

As hypersonic flight speeds and engines efficiencies increase, heat loads on an aircraft and it's engine increase. Because the temperature of the air flow is too high to cool the aircraft structure at hypersonic flight speeds, it is essential to use the aircraft fuel as the primary coolant. Endothermic fuels are liquid hydrocarbon aircraft fuels which are able to absorb the heat loads by undergoing endothermic reactions, such as thermal and catalytic cracking. The endothermic reactions are improved by catalysts which change the extent of reaction and product distribution. At high temperature, liquid hydrocarbons would lead to coke formation that can reduce the effectiveness of heat exchanger and cause rapid degradation of the catalyst, thus endothermic capacity of endothermic fuels is limited to the temperature at which coke doesn't form. In this study, the essential cooling technologies by applying endothermic fuels and the properties of the endothermic fuels are described.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.12
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• pp.41-46
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• 2018

In this research, numerical analysis was performed to determine the effects of hydrogen on biogas combustion for homogeneous charged compression ignition (HCCI) engines. The target engine specifications were a 2300cc displacement volume, 13:1 compression ratio, 15kW of electricity, and 1.2 bar boost pressure. The engine speed was fixed to 1800rpm. By varying the excess air ratio and hydrogen contents, the cylinder pressure, nitric oxide, and carbon dioxide were measured as a function of the hydrogen contents. According to preliminary studies related to the reaction mechanism for methane combustion and oxidation, a GRI 3.0 mechanism as the base mechanism was selected for HCCI combustion calculations describing the detailed reaction mechanism. By adding hydrogen, NO was increased while $CO_2$ was decreased. The cylinder pressure was also increased, having advanced timing for the maximum cylinder pressure and pressure rise region. Furthermore, lean operation limits were extended by adding hydrogen to the HCCI engine.

• Clean Technology
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• v.15 no.4
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• pp.253-257
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• 2009

The waste solution discharged form the LCD(Liquid Crystal Display) manufacturing process contains phosphoric acid, nitric acid, acetic acid and metal ions such Al and other impurities. In this study, vacuum evaporation and diffusion dialysis was developed to commercialize an efficient system for recovering the high-purity phosphoric acid and manufacturing monoammonium phosphate. By vacuum evaporation, almost 99% of nitric and acetic acid was removed. Also, by diffusion dialysis, about 97.5% of Al was removed. Monoammonium phosphate was manufactured from purified phosphoric acid and ammonium hydroxide. In order to get the optimum manufacturing condition, the molar ratio of ammonium hydroxide and phosphoric acid, pH and temperature was controlled. Using this optimum condition, we obtained the recovery rate of monoammonium phosphate of about 90%.

• Journal of The Korean Association For Science Education
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• v.22 no.2
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• pp.345-356
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• 2002

This study investigated the trends in the number of applicants and mean score and applicants' responses on the test items of 'science inquiry' of the College Scholastic Ability Test(CSAT) implemented for 3 years$(1999\;{\sim}2001)$. The results of this study were as follows: The percentage of applicants of science track for 1995 CSAT were 43.13%, but reduced to 29.5% for 2001 CSAT. And unlike other tracks, the percentage of male applicants, ranking above average, of science track was 65.58%, which is about twofold of female applicants(34.42%). The mean score of 'Science inquiry' was 58.6 in 1999, and 69.5 in 2001. And the score of the applicants, ranking above average, of humanity and social science course and science course, were 85.8 and 90.7 respectfully in 2001 CSAT. These high mean scores were caused by the policy of "easy CSAT" so called. Most of test items were developed to have difficulty 60-79% or above 80%. This easy CSAT provoked intense dispute about the discriminating power of CSAT. The mean score of male applicants was higher than that of female. But the difference decreases every year. Applicants were generally very good at solving tests focusing on process skills only but poor at solving tests related to physics or calling for two or more science concepts. Thus special measures to cope with the decrease in applicants, especially female applicants, for science track should be provided. To increase discriminating power of CSAT, it is recommended to develop test items with wider range of difficulty and to reduce test items which are focussing process skills and can be solved without any special science concepts. And special consideration should be given to teaching the content area with poor achievement and high actual difficulty compared to the expected.

• Clean Technology
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• v.26 no.4
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• pp.311-320
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• 2020

In this study, the photocatalytic degradation of rhodamine B (RhB), methyl orange (MO) and methylene blue (MB) was carried out under visible light irradiation using CdS and CdZnS/ZnO photocatalysts prepared by a simple precipitation method. This study focused on examining the effect of physicochemical properties of dye and photocatalyst on the reaction pathway of photocatalytic degradation. The prepared photocatalysts were characterized by XRD, UV-vis DRS and XPS. Both the CdS and CdZnS/ZnO photocatalysts exhibit an excellent absorption in the visible light and the UV light regions. It was observed that the photocatalytic degradation of MO proceeds via the same reaction mechanism on both the CdS and CdZnS/ZnO photocatalysts. However, the photocatalytic degradation of RhB and MB was found to proceed through a different reaction pathway on the CdS and CdZnS/ZnO catalysts. It is interesting to note that MB dimer was formed on the CdS catalyst at the beginning of the photocatalytic reaction, while the MB monomer was degraded during the overall photocatalytic reaction on CdZnS/ZnO. The above results may be mainly ascribed to the difference of band edge potential of the conduction band in the CdS and CdZnS/ZnO semiconductors and the adsorption property of dye on the catalysts.

• Proceedings of the Materials Research Society of Korea Conference
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• 2010.05a
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• pp.35.2-35.2
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• 2010

최근 $Cu(In,Ga)Se_2$(CIGS)와 같은 박막 태양전지에 대한 연구가 많은 관심을 끌고 있다. CIGS 태양전지의 광투과층으로 사용되고 있는 II-VI족 화합물 반도체인 CdS는 상온에서의 에너지 밴드 갭(band gap)이 2.42eV 정도로서, 가시광영역의 많은 빛을 투과시키고, 적절한 제작 조건하에서 비교적 낮은 비저항을 나타내기 때문에 널리 사용되고 있다. 하지만 CIGS 태양전지 연구는 주로 CIGS 흡수층 제조공정에 편중되어 있으며, CdS 버퍼층 공정조건에 대한 체계적인 연구가 부족하다고 판단된다. 습식공정인 Chemical Bath Deposition (CBD)에 의해 주로 제조되는 CdS는 단순한 제조공정에도 불구하고 CIGS 태양전지의 성능에 지대한 영향을 미치는 것으로 알려져 있다. 특히, CdS합성반응이 개시되기 전까지의 용액잔류시간 (dip time)은 CIGS내로의 Cd이온 농도를 결정하는 중요한 공정변수로 판단된다. CIGS 표면에 Cd이 도핑될 경우, CIGS는 n형 전도성을 갖는 얇은 층을 갖게 되어 전체적으로 n-CIGS/p-CIGS의 동종 접합을 형성하는 장점을 부여할 것으로 기대된다. 따라서 본 논문에서는 dip time을 주요변수로 하여 CIGS 태양전지의 성능에 미치는 영향을 주로 고찰하였다. Cd의 확산 정도는 secondary ion mass spectroscopy (SIMS)를 이용하여 정량화하였으며, 제조된 CIGS 태양전지의 전류-전압 특성과 상관성을 제시하고자 한다.

• Korean Journal of Child Education & Care
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• v.18 no.4
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• pp.65-89
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• 2018

Objective: The purpose of this study is to analyze the science concepts and teaching and learning methods presented in the science education-related activities of the Nuri Curriculum teacher guidebooks for ages 3-5. Methods: The research data included 772 activities related to science education in the teachers' guidebook. The analysis of science concepts was based on physical science (force and motion, physical structure, electricity and magnetism, light and shadow, sound properties), chemistry (material properties, material reaction), life science (organizational structure, growth and change, heredity and evolution, animal plant and human relationships), earth science (earth system interaction, earth system structure, and universe), engineering (designed world, engineering design, engineering, technology and society) and ecology (environment preservation). Teaching and learning methods were analyzed according to the types of small and large group activities and of free play activities. Results: Science concepts were mainly presented in the fields of engineering, chemistry, and life science commonly among children aged 3-5, whereas the concepts of physical science were lowly presented in all ages. Science concepts appeared mainly in the daily subjects of 'animal plant and nature', 'life tools', 'environment and life', and 'spring, summer, autumn and winter'. As the teaching and learning method, free paly activities (science area, free outdoor selection activity, math and manipulative activity) were mostly used for the ages of 3 and 4, and small and large group activities (cooking, story sharing, music activity) were for the age of 5. Conclusion/Implications: It is necessary to select the level of science area and concept that can be taught according to the age of children and the timing of the teaching.

• Journal of Oral Medicine and Pain
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• v.26 no.3
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• pp.181-187
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• 2001

스트레스가 인체의 항상성에 영향을 미쳐 다양한 질병 및 동통을 일으킬 수 있다는 것은 선학들의 연구에 의해 증명되어 왔다. 특히 정서적으로 중요한 구강안면영역에는 스트레스와 관련된 질병 및 동통이 많이 존재하는데, 이에대한 병리적 기전은 아직 뚜렷하게 밝혀져 있지 않다. 이에 저자는 스트레스와 말초 및 중추신경과의 병리적 관계를 알아보고자, 구속스트레스하에서 구강안면영역의 감각과 운동에 중요한 역할을 하는 삼차신경의 집합체인 삼차신경절과 뇌간조직의 단백질 변화를 western blot을 통해 살펴보았다. 실험동물은 생후 8주된 Sprague-Dawley계 웅성 백서 (323-367 g/bw)를 대조군 3마리, 실험군 15마리로 배정하였고 실험군은 실험 전기간에 걸쳐 구속스트레스를 부여하였다. 실험동물의 삼차신경절과 뇌간은 희생 즉시 적출되었으며, western blot을 시행하여 다음과 같은 결론을 얻었다. 1. 삼차신경절의 모든 군에서 약 18 KDa의 단백질이 균일하게 나타났다. 2. 뇌간의 모든 군에서 약 18 KDa 단백질이 발현되었으며, 정상 대조군, 실험 즉일, 1일, 3일, 7일에서는 뚜렷한 변화가 없었으나 실험 5일군에서는 현저한 감소를 보였다. 구속스트레스에 의해 뇌간의 5일군에서 약 18 KDa의 특수한 단백질이 뚜렷이 감소된 후 7일 군에서 다시 증가되었던 것은 스트레스에 의한 뇌간세포의 반응으로 생각되며, 뇌간에서와 다르게 삼차신경절에서는 그 변화가 나타나지 않았던 것은 스트레스에 대한 조직의 반응 차이라고 생각된다. 따라서 이를 명확하게 확인하기 위해서는 향후 수종의 스트레스와 관련된 단백질 변화에 대한 추가적인 연구가 필요하리라 사료된다.

• Proceedings of the Korean Society for the Gifted Conference
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• 2003.11a
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• pp.165-166
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• 2003

2002년 3월부터 영재교육법 시행령이 적용됨에 따라 과학기술부에서는 교육인적자원부, 부산광역시 교육청과의 협약을 통하여 부산과학고등학교를 과학영재학교로 지정하였으며 2003년 3월 신입생 입학 이후 현재까지 운영되고 있다. 과학영재를 조기에 발굴하여 맞춤식 교육을 체계적으로 실천함으로써 지식기반 사회를 선도할 수 있는 창의적인 과학영재를 육성하려는 과학영재학교의 설립목적에 부합되도록 계획, 운영, 평가되기 위해서 현재 진행되고 있는 운영 전반에 대하여 점검 및 분석이 이루어질 필요가 있다. 이에 과학영재학교 운영상의 주요 측면인 교육과정 운영 분야에 대하여 그 실태와 학생 반응을 분석하는데 본 연구의 목적이 있다. 과학영재학교의 교육과정 기본 방침은 과학 분야에 대한 깊은 이해와 논리적, 비판적, 창의적 사고력과 태도를 통하여 지식을 창출하는 자기 주도적 탐구자의 양성을 전제로 하고 있으며 교육과정 편제는 교과, 자율연구, 위탁교육 및 특별활동으로 구성되어있다. 교과에는 국어, 사회, 외국어, 예체능을 포함하는 보통교과와 수학, 과학, 정보과학을 포함하는 전공교과가 있다(과학영재학교 교수요목안내서, 2003). 본 연구에서 교육과정 편제, R&E, 교수학습 및 평가의 하위 영역별로 그 실태와 각 영역별 학생 설문 결과를 분석한 결과는 다음과 같다. 첫째, 영재학교 교육과정 편제 및 운영에 대한 학생들의 인식을 조사한 결과, 심화 선택과목의 학점 비중을 더 높여야한다는 의견과 보통교과의 학점을 줄이고 전공교과의 학점을 늘려야 한다는 의견이 상대적으로 높게 나타났다. 이러한 결과는 대상 학생들이 과학영재학교 선발과정에서 수학, 과학 각 분야별 우수자로 선발된 경우가 많아 학생 개인적으로 자신감을 가지는 과목만 집중적으로 학습하고자 하는 의도의 반영으로 볼 수 있다. 이와 관련하여 영재교육과정의 운영지침(이상천, 2002)에 의하면, 대학 수준의 내용을 그대로 도입하는 속진보다 창의성과 사고력 계발에 보다 충실할 수 있도록 내용의 폭을 넓히고 접근방법을 달리하는 심화 중심으로 교육과정을 구성하고 운영한다고 하였다. 그러나 현재 개발된 교육과정 편성과 운영은 창의성 교육의 구현보다는 압축형 속진 교육과정의 특성이 강하여, 이와 같은 운영지침을 실현하기 어려운 것이 현실이므로 교육과정 편제의 개선이나 운영지침에 적합한 교육내용의 개발이 시급히 이루어져야 할 것이다. 둘째, R&E(Research ＆ Education)는‘연구를 통한 교육’,‘교육을 통한 연구’를 의미하며 과학영재교육과정의 가장 큰 특징이라 할 수 있는 자율연구와 위탁교육을 위한 프로그램이다.