무선방송환경에서 거래관리를 위한 오류무관 동시성제어

학위논문(박사) - 한국과학기술원 : 경영공학전공, 2003.8, [ vii, 110 p. ]In order to provide information to numerous concurrent clients, broadcast delivery is attractive for use in a number of emerging database applications because it is independent of the number of users the applications are serving. However, the distribution of data over a broadcast channel cannot be reliable because an acknowledgement explosion phenomenon is raised when a reliable communication protocol of retransmissions and acknowledgements is applied to the broadcast channel. Therefore, a concurrency control scheme in wireless broadcasting environments should overcome broadcast errors because they are unavoidable when data is distributed over the broadcast channel. This thesis proposes a novel concurrency control scheme, called error-resilient concurrency control (RCC), which exploits broadcast delivery but is not vulnerable to broadcast errors in the wireless broadcasting environments. The performance of RCC was evaluated with an analytical model focusing on the effects of broadcast errors on concurrency control. The performance was also measured with a simulation model. The analytical results conformed to those of the simulation model. The results show that RCC is not only applicable to a broad range of broadcast error rates, but it also achieves better performance than the two compared models, the optimistic concurrency control scheme and the certification reports scheme.한국과학기술원 : 경영공학전공

Modulatization of National Technical Qulifications Related IT in General Clerical Fields

이 연구는 IT기술의 변화와 업무수행에서의 IT 활용능력의 일반화에 따라 국가기술자격 중 기초사무에 분류되어 있는 IT관련 자격으로서 워드프로세서와 컴퓨터활용능력 자격과 관련하여 새로운 기초사무 관련 IT 능력모형을 도출하고, 이를 토대로 모듈식 자격으로 개편하는 방안을 모색하기 위해 이루어졌다. 연구결과 워드프로세서, 스프레드시트, 데이터베이스, 프레젠테이션, 웹활용, 컴퓨터일반 6개 능력에 대해 30개 하위능력, 67개 세부하위능력을 도출하였다. 또한 능력변화에 따른 자격개정과 수요자의 요구에 따른 자격취득이 용이하도록 모듈식 자격으로의 개편방안으로서 ① 기초사무 IT능력별 모듈자격화, ② 기초사무 IT 능력간 연계성을 고려한 모듈자격화, ③ 단일자격종목 내 능력별 시험과목 모듈화, ④ 능력별 모듈자격화 및 종합자격 신설 등 네 가지 방안을 구안하였으며, 각 방안별로 자격의 관리？운영, 직업자격으로서의 사회적 위상, 검정능력의 유연성 및 확장성을 고려하여 장？단점을 도출하였다. 한편 기초사무 IT분야 국가기술자격의 모듈화에 따른 자격명칭, 검정 과목 및 방법, 등급체계, 응시자격 등 자격운영을 위해 필요한 사항을 제언하였다.The purpose of this study was to develop The IT competency model related to wordprocessor qualification and computer practical ability qualification which are part of national technical qualifications and to search for a plan to modify into modular qualifications based on the IT ability model. It was concluded that there were six key abilities, which were word, spreadsheet, database, presentation, using the web, general computer, and developed 30 subabilities and 67 detailed subabilities according to the key abilities. It is also developed modular qualification plans and suggested each plans’ strengths and weaknesses The plans are ① modular qualifications which are based each IT abilities ② modular qualifications which are considered each IT abilities relation, ③ single qualification and modular examination subjects, ④ modular qualifications which are based each IT abilities and establish total qualification. Moreover, this study suggested qualification title, examination subjects and methods, grade, test requirements and conditions