Mica에 대한 이산화티탄의 흡착에 관한 연구

강익균,한상현,김용권 慶熙大學校 1984 論文集 Vol.13 No.-

Titanium oxide was prepared by the hydrolysis of TiCl_4 and was coated on mica. The optical characteristics such as reflection and transmission of the latter was studied. The effects of concentrations of TiCl_4 on the rate of hydrolysis, particle size of hydrolysis product (Ti0_2), and crystal induction time, were found to be quite reverse to the general principle. Graphical analysises show that the crystal induction time was shorter as the concentra-tion of TiCl_4 decreased. By proper regulation of the condition of hydrolysis of TiCl_4 solution, mica pigments of colours ranging from silver-white to red was produced. Their maximum intensity of light reflection and maximum transmittance were from 300 to 800nm and from 400 to 700nm respectively.

Sol-Gel 코팅법에 의한 TiN/Al_2O_3/Tialon 복합체의 제조 및 분석에 관한 연구

姜益均,車銀姬,韓相鉉,金勇權 慶熙大學校 1990 論文集 Vol.19 No.-

TiN/Al_2O_3/Tialon comlposite was prepared by sol-gel processing of alumina sol, TiN, AIN, and Y_2O_3. The resultant composite was calcined at 900℃ and a number of test bars were cut from the composite to press uniaxially and isostatically at 20,000 psi and to sinter at 1650℃ and 1,700℃ for one hour in nitrogen atmosphere. Examination of the bar showed the structure of the composite to be a mixure of closest packed microcrytalline materials, and its mechanical property to be available for metal cutting, abrasive, protective, and decorative object ;

초등학교 과학 수행평가에 대한 교사의 인식

서승조,조태호,백남권,박강은,김성규,박장서 晋州敎育大學校 科學敎育硏究所 2001 科學敎育硏究 Vol.27 No.-

The purposes of this study are to examine how Science Performance Assesment is being well conducted in elementary schools and to check the teachers' awareness through surveying the actual condition. To achieve this purpose, the author, in this study, distributed questionnaire developed by researcher under supervision of academic advisor to the elementary school teachers in Gyeongnam province. Based on the data. the research results were mainly analyzed by the statistical method using Chi-square test. The survey was consisted of questions which was designed to perceive teachers' awareness about elementary school science performance assessment. The main findings of this study are summarized as follows', 1. Elementary teacher's are doing affirmative estimation about induction of performance assessment. 2. Most teacher are recognizing performance assessment right and teachers' understanding appeared high. 3. Material development of performance assessment is recognizing that people who have opinion which is special must develop. 4. The biggest problem of performance assessment fixing is recognizing that number of persons per class are many and amount of training courses is much also with the tribe during time. 5. It was recognizing positively whether it is in class improvement of performance assessment effect. 6. Teachers had awareness that confirm studies accomplishment degree through performance assessment, or will utilize to improvement material of teaching-learning method.

초등학교 교사들의 과학과 실험연수에 대한 의식 조사

서승조,조태호,백남권,김성규,박강은,정순호 晋州敎育大學校 科學敎育硏究所 2001 科學敎育硏究 Vol.27 No.-

This study investigated the perceptions of elementary school teachers' on the science experimental training course using closed-form questionnare. 437 elementary school teacher, 21 school, 14 cities and counties in Gyung Nam province were selected as the objects for researching these matters. The results were as follows; First, without system and holding type teachers choose on the training not the same time but their ability freely. Second, to extend the trust the composition of place and instructor must be based on professor and research in the national university of education. Third, the composition of the text must be made of scientific growth based on important experimental activities teaching strategy, the using of materials. It must be increase multimedia training course on the science education. Fourth, the method of training course it must be happen on the experiment and discussion and it is necessary to grow up training level. Fifth, the type of training it must not give the score. Therefore it will be free and comfortable without difficulties. In the results, the improvement of science experimental training course is compatible on the purpose and it will help on the science teaching-learning.

초등교사의 과학과 환경 교육에 대한 수업실태 분석 및 인식도

조태호,서승조,백남권,김성규,박강은,박원석 한국환경과학회 2002 한국환경과학회지 Vol.11 No.7

The purpose of this study was to analyze the elementary school teachers' perception toward the environment-related subjects in science education and to investigate their instructional methods in delivering the subjects in the classroom. The participants of this study were 300 elementary school teachers sampled from elementary schools in Kyung Nam Province. The findings of this study were as follows; First, more than half of the teachers surveyed showed that the environment-related units and contents in the science textbook were insufficient to the existing issues. Second, the large portion of teachers responded that the teaching materials in the textbook were insufficient to deliver the contents. Third, the largest portion of respondents replied that their preferred instructional method was a teacher-directed instruction followed by a case study approach. Fourth, in terms of the effectiveness of environmental education, both male and female teachers showed negative responses. Furthermore, male teachers were more negative than female teachers. Fifth, total means of their preference of the environment-related units was 3.13. The unit for sixth graders titled 'Environmental Pollution and Protecting Nature' showed the highest preference, whereas the unit for fifth graders titled 'Structure and Functions of Plants' showed the lowest preference. Sixth, there was no statistically significance in gender and their working areas. Seventh, there was statistically significant differences between male and female teachers in terms of teaching experience. In detail, the teachers with 5 to 9 teaching experience showed the lowest scores, while the teacher with more than 15 years teaching experience showed the highest scores in their perception of the units. Eighth, there was a significant difference between two groups in terms of their educational background. For example, two-year college graduates showed higher preference than four-year college graduates.

초등학교 과학과 에너지영역의 STS 내용 변천

서승조,조태호,백남권,김성규,박강은,정인재 晋州敎育大學校 科學敎育硏究所 2001 科學敎育硏究 Vol.27 No.-

This research compared and analyzed the content ratio of the STS (Science-Technology-Society) Education and subjects and types of learning activities to determine the characteristics of STS education in science classes of elementary schools. In the 5th curriculum, the STS-related content on energy section took up 6.6% , in the 6th curriculum, compared with that of the 5th, the STS content ratio on the energy section increased 7.9% and the STS content on the energy section in the 7th curriculum showed an increased 20.8% proportion. Comparing the main subjects of the STS in the energy section for the science class according to curriculum in the 5th, they obviously have influenced technological development, energy, the development of space studies, and sociology of science, in that order. In the 6th curriculum. compared with that of the 5th, the energy section decreased and the sociology of science increased much. There were no significant changes in other subjects. In the 7th, the STS elements were distributed evenly but the extent of the STS main subjects reduced compared to that of the 6th. The STS education activities represented in science textbooks of elementary schools were mainly executed through discussion, research activities, and actual activities. Other activities such as role-playing, simulation tests, problem solving and decision making, data analysis, research design, case studies, etc. were hardly made.

Improvement of low gray-level linearity using perceived luminance of human visual system in PDP-TV

Kang, Sung-Jin,Do, Hyun-Chul,Cho, Byung-Gwon,Chien, Sung-Il,Tae, Heung-Sik IEEE 2005 IEEE TRANSACTIONS ON CONSUMER ELECTRONICS - Vol.51 No.1

One of the factors deteriorating the image quality of PDP-TV is the low gray-level contour occurring mainly due to inverse gamma correction. From the viewpoint of human visual perception, the low gray-level contour becomes more serious because of the nonlinear output luminance of PDP at low gray-levels. In this paper, a modified inverse gamma correction method and a gray-level linearization technique considering human visual perception are proposed for enhancing image quality at low gray-levels.

Design of a Cylindrical Flexure Jointed Stewart Platform for Aligning the Condenser in an X-ray Microscope

Kang Sung-Hoon,Kang Dong-Woo,Gweon Dae-Gab,Yoon Gwon-Ha,Min Jin-Young Korean Society for Precision Engineering 2006 International Journal of Precision Engineering and Vol.7 No.3

This paper proposes a new type of six degree-of-freedom fine positioner that can be used to align the condenser in X-ray microscopy precisely. The new concept was based on the requirements for an X-ray microscope. A proposed modeling method was used to obtain an optimal design, which was verified with a finite element analysis. The fine positioner was then constructed and an experiment was used to validate its performance.

Design of a Cylindrical Flexure Jointed Stewart Platform for Aligning the Condenser in an X-ray Microscope

Sung-hoon Kang,Dong Woo Kang,Dae-Gab Gweon,Gwon-Ha Yoon,Jin Young Min 한국정밀공학회 2006 International Journal of Precision Engineering and Vol.7 No.3

This paper proposes a new type of six degree-of-freedom fine positioner thai can be used to align the condenser in X-ray microscopy precisely. The new concept was based on the requirements for an X-ray microscope. A proposed modeling method was used to obtain an optimal design, which was verified with a finite element analysis. The fine positioner was then constructed and an experiment was used to validate its performance.

Review : Gastrointestinal Stent Update

( Sung Gwon Kang ) The Editorial Office of Gut and Liver 2010 Gut and Liver Vol.4 No.s1

The use of self-expanding metallic stents in the upper gastrointestinal tract, placed under radiologic imaging or endoscopic guidance, is the current treatment of choice for the palliation of malignant gastrointestinal outlet obstructions. Advances in metallic stent design and delivery systems have progressed to the stage where this treatment is now considered a minimally invasive therapy. Metallic stent placement will broaden further into the field of nonsurgical therapy for the gastrointestinal tract. To date, metallic stents placed in the esophagus, gastric outlet, colorectum, and bile ducts are not intended to be curative, but rather to provide a palliative treatment for obstructions. The evolution of metallic stent technology will render such procedures not only palliative but also therapeutic, by enabling local drug delivery, and the use of biodegradable materials will reduce procedure-related complications. (Gut Liver 2010;4(Suppl. 1):S19-24)