PCL-MMT 나노복합재료의 기계적 성질과 생분해에 관한 연구

최현국 ( Hyun-kuk Choi ),이영세 ( Young-sei Lee ),박재경 ( Jae-kyeung Park ) 한국산업융합학회 2005 한국산업융합학회 논문집 Vol.8 No.1

PCL were intercalated into organically modified MMT(PCL-MMT) at 80°C for 4hrs to prepare the PCL-MMT nanocomposite. PCL-MMT and PCL were mixed mechanically with two-roll mill at 150 ℃ for 15mins. From the results of XRD and TEM, it were found that PCL-MMT nanocomposite were prepared. And mechanical properties and biodegradation of nanocomposite have been investigated by tensile meter and biodegradability analysis experiment. Because of MMT dispersed homogeneously in PCL matrix, the Young's modulus of the nanocomposite was found to be excellent. But the tensile strength and elongation were decreased as increase of MMT. And MMT dispersed in PCL matrix was almost not affected on the biodegradation of PCL.

정상안에서 Pressure Eye Patch가 외안부에 미치는 영향

김재호,온영훈,신환호,정순국 순천향의학연구소 1996 Journal of Soonchunhyang Medical Science Vol.2 No.1

Immobilizaiton of eyelids by pressure eye patch may relieve photophobia and some ocular pain. Although many ophthalmologists prefer pressure eye patch after operation and ocular trauma, it was not considered that eye patch may induce some ocular symptoms. We therefore studied the effects of pressure eye patch in normal eyes of healthy young adults. Thirty two medical students and doctors participated in this study. The pressure eye patch in normal eyes of healthy young adults. Thirty two medical students and doctors participated in this study. The pressure eye patch was applied for 14 hours on one eye of participants. Both eyes of all participants were examined twice, before and after patching. The examination included opthalmic examination and questionnaire of subject symptoms. Each symptom and sign was graded on a scale from 0 to 3. The scores were statistically evaluated by using the the Wilcoxon signed-rank test. In group 1 (patched eyes), 30 of 32 participants had clinical symptoms and signs. In comparison between group 1 (patched eyes) and group 2 (unpatched eyes), participants in the group 1 had more symptoms and signs such as discomfort (P<0.01), itching (P<0.01), congestion (P<0.01) and irregular astigmatism (P<0.01). Thus we concluded that complicaitons of varialbe severity and shape were induced by eye patch in normal eyes. So we considered that Eye Patch ater operation and trauma may contribute the above mentioned complicaitons and we must doing this procedure cautously.

위암 환자에서 세포성 면역 기능에 관한 연구

이재익,윤일국,이종선,김종완,장준,안정기,송민호,정현용,이헌영,김삼용,김영건 충남대학교 암연구소 1991 癌共同硏究所 硏究誌 Vol.1 No.1

We performed a variety of lymphocyte stimulation tests, delayed hypersensitivity skin tests, and enumeration of several lymphocyte subpopulations in 21 patients with gastric cancer who did not receive any form of anticancer therapy, and in 20 healthy controls. The gastric cancer patients had significantly decreased number and total score of positive reactions in delayed hypersensitivity skin tests compared with the healthy controls. The percent of CD_(4) positive lymphocytes in the gastric cancer patients was significantly decreased compared to the normal control subjects, but it had no correlation with the total score of delayed cutaneous hypersensitivity reactions. The ratio of helper to suppressor cells was lower in the cancer group. The uptake of 3H-thymidine was markedly depressed in cancer patients when stimulated with various mitogens. There was little correlation between any of the stimulation tests and any of the lymphocyte subpopulation proportions to delayed hypersensitivity cutaneous reactions. Optimal proliferative response was found in lymphocytes stimulated with 10 micrograms of concanavalin-A and 10 microgram of phytohemagglutinin. Advanced stage patients had greatly depressed delayed hypersensitivity skin reactions and proliferative responses to mitogens compared with localized diseases. These results suggest that gastric cancer patients have depressed cellular immune functions, which mainly result from the decreased helper cells and defects in functional proliferative response to mitogens. Interleukin-2 and interferon-gamma restored the in vitro proliferative response of lymphocyte in patients with gastric cancer.

정보화시대의 공동체 : 정보화의 진전과 기업·소비자 관계 변화를 중심으로

이대식,김성국,김영삼,신종국,임정덕,조영복,조정문 釜山大學校 商科大學 2000 釜山商大論集 Vol.71 No.-

In this study, we questioned about the possibility of the formation of the new community like relationship at the market on the contrary to the traditional market relationship. We conjectured that kind of new community like relationship may possibly arise because of wide spread of new information technology at market behavior of both consumer and producer side. Traditional buyer-seller relationship was characterized as an anonymous one-shot relationship, however, recent changes were mainly emphasized the rich mutual interactions from both sides. Producers needs more consumer side informations as well as consumers begin to participate on production side at more organized level. Some theoretical studies predict that more rich social relationship will appear at the market since the adoption and wide spread of new information technology. We assume that main functions and ingredients of the community are first, the coordination mechanism which reduces conflicts among community members and second, functional efficiency which meets the common needs of community and third, communicational rationality which enhances the integrity of community members. We surveyed about 100 small and medium sized firms located at Pusan and Kyung-Nam area in order to find out whether firms have community like relationship with their consumers. We fine that most of firms realize the impotance of consumer networks, however most of firms consider this kind of network as a marketing strategy and a source of product design instead of more community oriented characteristics like mutual trust building and social interactions.

보편적 이동전화 서비스를 위한 방안에 관한 연구

김영곤,노순국,박창균 조선대학교 전자정보통신연구소 2000 電子情報通信硏究所論文誌 Vol.3 No.1

Mobile phone service one of services for the realization of high information society of 21C, has made and repeated a rapid development. Now our country, the subscriber number of mobile communication has outrun the one of wire telephone But several problems caused by that has been making appearance on the stage as a new social phenomenon are appeared In this study at time of information and communication in 21C one of the problems caused by mobile phone rapidly developing, to choose universal service of mobile phone, as compare the cases of many advanced countries with present our conutry situation, we propose that the methods for the offer of universal service of mobile phone

單純便秘症의 治療

尹榮國 慶北大學校 醫科大學 1980 慶北醫大誌 Vol.21 No.2

Obstinate constipation is one of the most frequent conditions which the physician is called upon to treat. In spite of its frequent occurrence, there is probably no other disorder which is so often badly managed. This is unfortunate, since the results of adequate treatment are usually very satisfactory. All patients with simple constipation must be managed by conservative methods initially. Physiologic bowel action is preferable to the use of cathartics. Thus, if possible, exercise, a diet adequate in fiber content, and establishment of a proper "habit time" should be employed first. If these measures are ineffective, laxatives and/or enemas may be necessary but chronic use of cathartics or enema is contraindicated. Colon irrigation has no place in the management of ordinary constipation. It may be required for the removal of fecal impactions in case of megacolon, or in very senile patients, and are necessary occasionally in the constipation in the insane. The most of constipations usually respond well to the medical treatment, but some of them are intractable for a long period of time. Therefore surgical intervention is reserved for these severe intractable types of chronic constipation. Several operative procedures may be done successfully, i.e., plication of the colon, by-pass surgery, adhesiolysis, sympathetic ganglionectomy, and excision of the affected colon. To evaluate the length of the resection of the affected segment of the colon, "Barium intestinogram" is the most practical and valuable method. Surgical treatment of simple constipation has long been a somewhat provocative subject. Long-term follow-up will be required before surgical intervention in the treatment of constipation can be accepted without provocation.

葡萄잎茶의 開發을 위한 탄닌과 카페인咸量의 測定

李暎鍾,黃安國 大田大學校 1987 論文集 Vol.6 No.2

지구과학의 地震 학습을 위한 STS 프로그램의 개발

주국영,김종희,김상달 부산대학교 사범대학 과학교육연구소 1997 科學敎育硏究報 Vol.24 No.-

과학적 소양을 갖춘 시민 양성이 오늘날 과학교육의 중요한 목적 중의 하나임은 주지의 사실이다. 이를 위한 교육방법의 하나인 STS 교육은 우리나라에서도 그 중요성이 크게 인정되고 있는 형편이다. STS 교육을 활성화하기 위해서는 실제로 우리 나라의 교육 환경 하에서 활용할 수 있는 STS 프로그램, 진행을 위한 안내서 및 기본 자료의 개발이 필요하다. 본 연구에서는 이러한 점들을 고려하여, 학습자들이 교수-학습 활동의 중심이 되며 교사는 조력자로서의 역할을 하는 STS 수업의 실제 상황을 예시하고, 이 과정에서 적용한 교수-학습 방법과 활용한 자료들을 바탕으로 고등학교 지구과학의 지진 분야 학습을 위한 STS 프로그램을 개발하여 제시하여 지구과학 수업에서 STS 교육이 가능하도록 하는데 도움이 되고자 한다. It is a well known fact that it is a one of important objects of science education today to bring up citizens with scientific attainments. As a way to achieve the above object, STS's importance is being highly emphasized. To activate STS education, it is needed to develop STS programs, guide books and fundamental materials. Considering these sectors, this study shall present actual situations of STS education in which students are at the center of teaching and learning process and teachers are assistants. Based on teaching learning methods and material applied in the above process, this study shall help to enable STS in earth science by developing and presenting STS program for earthquake portion in high school earth science.

최근 사범대학 수학교육과 교육과정 개정 현황 : 1997년까지 개정된 교육과정을 중심으로

김영국 서원대학교 교육연구소 1999 敎育發展 Vol.18 No.1

Recently, Korean teacher's colleges have confronted with problems of substantiality and the over - production of prospective teachers. In fact, these problems were caused by recent fast growth in the number of universities and enrolled students. To coup with theme problems, from 1996, all teacher's college began to study the reformation of curricula which could facilitate a major-minor system or double major system. For this, the main idea was to reduce the students' burden of getting necessary credits for graduation. To inspire the advancement of teachers education, the Ministry of Education had planed to evaluate all teacher's college comprehensively in 1998. Among many evaluation items, the reformation of curriculum occupied the most important portion. In this paper, I investigated the recent curriculum reformative trends of departments of mathematics education and made some suggestions which must be taken into consideration in applying the new one. They are listed as follow. (1) The structure of the newly reformed curriculum followed the former styles. i.e., the new curricula kept the liberal art area, teaching professional category, math. category and math. educational category. Changes were made only in the ratio of credits among these categories. (2) The results proved to be increase of total credits for graduation and math. education category. But the minimum credits of liberal arts and mathematics categories decreased heavily. To facilitate the double major systems and major-minor systems, there had been many recommendations to reduce the minimum credits for graduation to 130. On the contrary, the reformed result showed that average credits increased by 4.4 to 144.4. They reduced the credits of required subjects only. (3) Almost all mathematics education processors think that only with the credits of the required subjects, it is impossible for students to be well equipped with mathematics knowledge which is required for competent math. teachers. To cope with the shortage of the credits, we recommend to devide the courses in mathematics category into two groups and to apply different teaching methods. First, considering the allocated credits, select a group of principal courses which are closely related with the four basic fields of school mathematics. Then, the teaching of these courses should be done from a pure mathematical point of view, strictly to their mathematical nature. The other complementary courses which connect the principal courses with secondary school math., would be better if coordinated with math education courses. (4) Since the credits of teaching professional category are reduced, We recommend all courses in this category should be made and taught in connection with math. education courses. Through this, we could increase the relationship among the teaching professional category, math. education category, and the group of non principal mathematics. (5) In the reformed curriculum, the credits of teaching practicum course proved to be increased only average 0.7 credits. The 2.7 credits are far behind the expectations. This course gives students not only teacher experience, but also opportunities to establish themselves more firmly as secondary school teachers. So, it would be better to strengthen this course.

유사체액에서의 전기화학적 처리가 티타늄 표면의 인산갈슘 흡착에 미치는 영향

조국현,김문영,송광엽,배태성,이민호 大韓齒科器材學會 2002 대한치과재료학회지 Vol.29 No.3

This study was performed to examine the effect of electrochemical treatment on the precipitation of apatite-like calcium phosphate in a simulated body fluid. Titanium plates of 20×20×1 ㎣ in dimensions were polished sequentially from #600 to #2,000 emery paper and one surface of each specimen was received an additional polishing sequence through 0.1㎛ alumina paste. To improve the bioactivity of titanium plates, they were electrochemically treated at 100 mA for 20 min in an electrolyte containing the calcium and phosphate ions, and the Hanks' solution with pH 7.4 at 36.5℃ for 30 days, and the surfaces were examined with X-ray diffractometer(XRD), scanning electron microscope(SEM) and X-ray photoemission spectroscopy(XPS). Precipitation of calcium phosphate and CaO were observed on the electrochemically treated titanium surface in a simulated body fluid after treatment at 600℃. Precipitation of calcium phosphate was densified and coarsened with increasing the temperature of the electrolyte solution in the range of 20-80℃. The calcium phosphate contained phosphate in the form of Po₄^3-, HPO₄^2-, and H₂PO₄^-.