Design of Fluorinated Cyanoacrylates to Control Adhesiveness of Liquid Embolic Materials

학위논문(석사)--서울대학교 대학원 :공과대학 재료공학부,2020. 2. 안철희.Embolotherapy is a method of inserting a catheter into the body to block the vessel or necrosis the tissue by infusion of an embolic materials. Embolic materials are classified according to the location of the lesion of vessel or the disease. Cyanoacrylate, one of the liquid embolic materials, is used in clinic with tantalum powder or oil with radiopacity. In order to improve this, in the previous study, the cyanoacrylate which have radiopacity was designed and synthesized. This new cyanoacrylate monomer has a problem that polymerization of cyanoacrylate monomer is decreased when oil is added to reduce adhesiveness. To improve this, various fluorinated cyanoacrylates were designed and three monomer ( named F, CF, FF) were synthesized according to the fluorine content and carbon chain length of side group. The polymerization rate and adhesiveness of mixture of monomer and oil with ratio 1:0 to 1:3 were measured and compared Histoacryl® which already used in clinical purpose. As a result, it was confirmed that the polymerization rate was accelerated as fluorine content was increased. In addition, the polymerization rate of monomer FF ,the monomer with highest fluorine content among three monomers, was not as slow as the other monomer when oil is added. And at the same time, the adhesiveness was decreased with similar amount of other monomers. In conclusion, mixture of monomer FF and oil has fastest polymerization rate and similar adhesiveness with other monomers. Through it is expected to be used as a replaced cyanoacrylate in composition in previous study.1. 서론 1 2. 실험 방법 6 2.1. 불소화 시아노 아크릴레이트의 합성 6 2.2.1. 모노머 F, CF의 합성 6 2.2.2. 모노머 FF의 합성 6 2.2. In vitro 중합 속도 실험 9 2.3. In vitro 접착력 실험 11 3. 실험 결과 및 고찰 13 3.1. 디프로텍션 조건 최적화 13 3.2. 불소화 모노머의 특성 16 3.3. In vitro 중합 속도 실험 16 3.4. In vitro 접착력 실험 22 4. 결론 25 5. 참고문헌 28Maste

An Empirical Analysis on Learning Organizational Traits According to Typology of Quasi-Governmental Organizations: the Context of Debureaucratization

본 연구는 최근에 글로벌 경제구조와 지식기반사회에서 정부 서비스의 집행과 전달의 주요 조직인 준정부(Quasi-government) 조직을 대상으로 학습조직 메커니즘의 특성 및 수준을 파악하여 탈관료제의 수준을 실증 분석하며, 창의적이며 혁신적인 변화를 주도할 수 있는 학습조직 문화를 형성하기 위한 정책적 시사점을 제시하고자 한다. 분석결과를 종합하면, 시장 수요에 민감한 준정부조직의 학습조직이 환경변화에 적절히 대응하기 위해 폭넓게 확산되어 있었으며, 곧 상대적으로 높은 탈관료화를 성취한 것으로 보인다. 반면, 관리형 준정부조직은 조직의 기능과 역할의 특성상 학습조직의 확산의 편차를 크게 보이고, 전반적으로 낮은 학습조직 수준을 보인다. 이는 부분적으로 탈관료제화가 확산되었고, 일부 부분에서 탈관료제화가 더딘 상황이라는 것을 확인할 수 있다. 정책적 시사점으로는 첫째, 관료제의 문제를 완화 및 해소하기 위한 방안으로 환경과의 개방성을 높이고 지속적인 교류를 보장해야 하는 것이 필요하다. 둘째, 학습조직의 수준차이를 심하게 보이는 대졸 학력, 중간관리자․사원대리 직급, 일반행정직에서 자율적인 학습활동 여건을 실질적으로 제공해야 한다. 따라서 학습조직 활성화를 위한 교육과 업무방식 전환, 세미나, 자체 워크숍 등 다양한 형태의 학습조직 활성화 지원이 추진될 필요가 있다. 마지막으로 소통과 협력의 부족으로 조직내에 의견을 반영하지 못하는 낮은 직급과 여성에게 조직 차원에서 의사소통을 위한 다양한 제도가 실질적으로 운영되어야 할 것이다. This study aimed to analyze empirically the level of the debureaucratization by examining the traits and degrees of learning organization in quasi-government organizations that are primary institutions recently delivering and implementing governmental services in global economic structures and in information-basis society, and secondly to suggest policy implications for establishing a culture of learning organizations that leads to creative and innovative changes. According to the results, learning organizations more sensitive to the market among the quasi-government organizations has spread more in an appropriate response to environmental changes, and also show that it has achieved relatively high debureaucratization. On the other hand, the more management-oriented quasi-government organization shows various differences in dissemination of the traits of learning organizations because of the role and the function of the organization and generally shows a low level of learning organization. Several policy implications are suggested. First, continuous interaction with the organizational environment and expanding openness to the environment are necessary for the purpose of alleviating and resolving the problems of bureaucratic organizations. Secondly, leaders of organizations should supply opportunities and conditions of autonomous learning activity to general administrators, to middle-class managers and low-class employees, and to those who have graduated from university, showing deeply different levels of learning organization traits. It is necessary to back up different learning activities such as workshops, seminars, and to change work and educational methods. Third, different institutions for communication should be operated within an organizational level for women and for grades who cannot express their opinion enough intheir organization because of a shortage of cooperation and communication.이 논문은 2010년도 정부재원(교육과학기술부 인문사회연구역량강화사업비)으로 한국연구재단 지원을 받아 연구되었음(NRF-2010-413-B00024)

The Time-Spatio Destination Choice of Shopping Trips : A Case Study of Weekday Shopping Trips Workers in Seoul

This study based on the time-geographic concepts aims to investigate how workers choose the destinations of shopping trips, ie. the choice set. The study posits that the choice set should be understood first in order to understand the choice patterns of specific shopping places, because the formation of a choice set precedes the actual choices of the shopping places. In other words, eery specific shopping place cannot be considered as an element of choice set for everyone. A travel-diary survey was conducted in Spring 1994, to collect data of weekday shopping trips of workers in Seoul. This study treated each purchase as the unit of analysis, and time as well as space were included as the objects of a choice. Using the cluster analysis technique, the time-spatio types of choice sets were identified, and then the constraint-variables reflecting the relationship between the individual and the society were derived. A logit model was employed to investigate the relation ship between the choices of time-spatio types and the constraint-variables. The major findings of the analysis are as follows

0-Hecke 대수위에서 정의된 Cartan invariants에 대해

Thesis (master`s)--서울대학교 대학원 :수학과,2000.Maste