공작기계 주축계의 오일에어윤활특성에 관한 연구

김석일,최대봉 한국항공대학 항공문제연구소 1992 航空問題硏究所 硏究誌 Vol.2 No.-

최근 오일에어윤활방법은 고속용 구름베어링에 대한 효과적인 윤활방법의 하나로서 많은 주목을 받고 있다. 본 연구에서는 공작기계의 생산성과 가공정밀도를 향상시키기 위한 노력의 일환으로 오일에어윤활방법에 기초를 둔 공작기계용 고속주축계를 개발하였다. 그리고 개발된 고속주축계의 성능을 평가하기 위한 일련의 윤활실험을 수행하였다. 특히 공작기계 주축계의 고속화에서 고려해야 할 윤활조건과 구조설계조건을 도출하기 위해서 공급유량, 주축회전수, 그리고 주축계의 구조가 베어링의 온도상승, 베어링의 온도분포, 그리고 주축계의 마찰토오크에 미치는 영향을 고찰하였다. Recently the oil-air lubrication method has attracted special interest as one of the effective lubrication methods for a high-speed rolling bearing. In this study, the high speed spindle system of machine tools based on the oil-air lubrication method is developed to reduce the machining time and to improve the machining accuracy. And a lubrication experiment for evaluating the performance of the developed spindle system is carried out. Especially, in order to establish the lubrication and structural design conditions related to the development of a high-speed spindle system, the effects of oil supply rate, rotational spindle speed and spindle system structure on the bearing temperature rise, bearing temperature distribution and frictional torque are investigated.

삼차동맥존속증을 동반한 정중엽 다리뇌경색

하윤석,김명국,유봉구 고신대학교 의과대학 2010 고신대학교 의과대학 학술지 Vol.25 No.2

Persistent trigeminal artery (PTA) is the most frequently observed fetal anastomosis between the carotid and vertebrobasilar circulations. PTA is usually associated with hypoplasia or aplasia of the vertebrobasilar artery. A 56-year-old woman presented with right hemiparesis and dysarthria. Brain MRI showed acute infarction in the right paramedian pons. CT angiogram revealed right persistent trigeminal artery and hypoplasia of the proximal basilar artery

두경부에 발생한 방선균증 3예

홍석중,주준범,김용재,이봉재 대한이비인후과학회 2000 대한이비인후과학회지 두경부외과학 Vol.43 No.11

신경섬유종증(렉클링하우젠병)에 의한 급사 1예 보고

이봉우,서중석,권태정,이원태 大韓法醫學會 2000 대한법의학회지 Vol.24 No.1

Neurofibromatosis type1(von Recklinghausen's disease) is characterized by multiple skin tumors and abnormal cutaneous pigmentation(cafe au lait spots). Unlikely the solitary neurofibroma, those encountered in von Recklinghausen's disease may cause significant morbidity. The vasculopathy, although poorly recognized manifestation of von Recklinghausen's neurofibromatosisis a major case of fatal cases. One of its most dramatic presentation is the spontaneous hemothorax. We report a case of Von Recklinghausen's disease with multiple neurofibromatosis accompanying intrathoracic hemorrhage due to vascular rupture, which is the first legal autopsy case in Korea.

진화 알고리즘을 이용한 충격강성설계에 관한 연구

조석수,주원식,이선봉 東亞大學校 大學院 1997 大學院論文集 Vol.22 No.-

Impact loads may be expected in many of the engineering applications of composites. The suitability of composites for such applications is determined not only by the usual parameters, but its impact or energy-absorbing properties. Genetic algorithms(GA) is probabilistic optimization technique by principle of natural genetics and natural selection and neural networks(NN) is useful for predication operation on the basis of learned data. Therefore, This study presents optimization techniques on the basis of genetic algorithms and neural networks to minimum stiffness and weight design of laminated composites.

다발성 모기질종 1예

신봉석,정병수,최규철 朝鮮大學校 附設 醫學硏究所 2008 The Medical Journal of Chosun University Vol.33 No.2

Pilomatricoma, often called calcifying epithelioma of Malherbe, is a tumor with differentiation toward hair cells, particularly hair matrix cells. It presents as a firm, deep-seated nodule that is covered by normal or pink skin. It is occuring usually as a single lesion which is most commonly found on the face, neck, or proximal upper extremity. Multiple lesions are quite unusual, comprising only 2-3.5% of cases. A 32-year old man had 3 subcutaneous nodules on the both upper extremities. Histological findings of the lesion showed the typical pattern of pilomatricoma. We presented herein one case of multiple pilomatricoma with the review of literatures.

폐 림프관확장증 3예 보고

이봉우,서중석 大韓法醫學會 1999 대한법의학회지 Vol.23 No.1

Congenital pulmonary lymphangiectasis is a rare cause of severe respiratory distress in the newborn period and most of these patients die, usually within the first 24 hours of life. The light microscopic characteristics of the lungs are a network of partly tubular, partly cystically enlarged lymph vessels with-in large areas of connective tissue and they have thin walls lined by endothelium. Also congenital pulmonary lymphangiectasis is closely associated with cardiovascular malformation, and most frequently occurs in the clinical setting of congenital heart disease with or without pulmonary venous obstruction(total anomalous venous return, atresia of large pulmonary veins). The authors describe three typical cases of congenital pulmonary lymphangiectasis.

학교교육에서의 교육과정의 의미에 관한 후기구조주의적 이해

김봉석 仁川敎育大學校 初等敎育硏究所 1997 교육논총 Vol.14 No.-

This study was written to investigate the meaning of school-curriculum in terms of a poststructuralist perspective. Traditionally, generally and narrowly, curriculum means a teaching plan or teaching program which is intended to teach students systematically. It is a bundle or body of knowledge, skills, attributes and values that are deserve to teach in schooling. This view implies that curriculum has a role which restricts and products a personalities/subjectivities of students. That is, a student is formed in accordance with the intention of 'the thing to learn in school.' And this technological and systematic meaning of curriculum is criticised by the curricularists, so called 'reconceptualists,' as the main causality of do-humanizing education and students. But, these critics have ignored in the curriculum field by the fact that they didn't suggest practical alternatives in the process of education and reduced to a nihilistic viewpoint with regard to knowledge-teaching. Here, the poststructuralist approach to curriculum is suggested to understand the identification and implication on the school-curriculum as an alternative perspective to a positivist and essentialist view of curriculum. To understand curriculum as poststructuralist text, we should regard the curriculum as a series of discourse on educating pupils. As a discourse, the curriculum plays an important role that forms and produces the group-subjectivity of students. For poststructuralists, discourse, which includes knowledge, does not represent reality. For poststructuralists, discourse constructs reality. Really, so the curriculum is. The curriculum as a discourse constructs the reality of child that learns knowledge, skills, attributes and values in school. We call this point of view in poststructuralism 'the genealogy of knowledge' in accordance with Michel Foucault. As a result, the school-curriculum is a displinary knowledge with related to social power, which makes the learning-subject(the learner) the object that are subjected to discipline or subject-matter as curricular.

1930년대 전반기 프로연극의 대중화운동 연구

정봉석 동아대학교 1992 국어국문학 Vol.11 No.-

연약지반에 설치된 조립질 말뚝의 지지력 특성

李鳳職,裵佑錫 충주대 산업과학기술연구소 2000 産業科學論文集 Vol.8 No.-

This paper presents the performance of ground treatment to support road embankment on soft ground. The long-term settlement characteristics of refuse landfill were analyzed by Sower(1973);Yen and Scanlon(1975). As a result of field test, the predicted settlement exceed the allowable settlement and ultimate bearing capacity is not satisfied. Therefore, the ground was treated by stone columns. The effectiveness of dynamic replacement was verified by Standard Penetration Test(SPT), Pressure Meter Test(PMT) performed before, during and after construction of the stone columns. From the pressure meter test, estimation of critical embedded ratio to classify the failure mechanisms, critical and yielding pressure on treated and untreated ground is suggested. Also deformation modulus of stone columns and untreated ground is suggested. The results indicated that the settlement of the treated foundation should be reduced to about 70 percent and the bearing capacity should be increased to about 60 percent comparing with the treatment. Due to the non-homogeneity of refuse landfill, stress concentration factors were distributed in wild range.