응용 데이타베이스 시스템 保安 向上을 爲한 接近 統制

강재화 東國大學校 情報産業大學院 1993 국내석사

금강과 새만금호 주변 갯벌에서의 다모류 군집구조

강재화 국립군산대학교 2025 국내석사

This study was conducted to investigate the benthic community structures of polychaete worms in the intertidal zones of Sinsi-do and Wi-do, influenced by the discharge from the Saemangeum Lake and the Geum River on the west coast of Korea. Seasonal surveys of benthic organisms were conducted at two stations along the intertidal zone of Wi-do from March 2023 to October 2023. Similarly, seasonal surveys of benthic polychaetes were conducted at three stations in the intertidal zone of the Geum River estuary and Sinsido from April 2023 to January 2024. The habitat conditions such as water temperature, salinity, grain size, TOC (total organic carbon), and Chl-a (chlorophyll-a) were monitored. There was a weak salinity gradient between sites, ranging from 24.4 psu in the tidal flats of the Geum River to 30.4 psu and 32.8 psu in the tidal flats of Sinsi-do and Wi-do, respectively. A total of 26 species of polychaetes occurred in the tidal flats of Wi-do with highest species diversity compared to those near the Geum River and Sinsi-do. The dominant species were different between tidal flats; in Wi-do, they were Scoloplos armiger, Heteromastus koreanus and Aricidea pacifica while those in mudflats of the Geum River estuary was Hediste japonica known as a typical brackish water species in the west coast of Korea. The dominant polychaete species in the Sinsi-do tidal flats were Cirriformia tentaculata, H. koreanus, and H. japonica. The presence of H. japonica in Sinsi-do tidal flats suggests that Sinsi-do tidal flats are likely influenced by the outflow from Saemangeum Lake toward Sinsi-do tidal flat. The most dominant feeding types in both Sinsi-do and Wi-do were BMX (burrowing, motile, non-jawed) and SDT (surface deposit-feeding, discrete, tentaculate), showing similar trends. In contrast, the most dominant feeding type in the Geum River estuary was SMJ (surface deposit-feeding, motile, jawed) represented by H. japonica. The Geum River estuary is the area most influenced by freshwater among the three regions, and polychaete communities are most affected by organic matter content and TOC (Total Organic Carbon). Sinsido and Wido, being island areas, showed the highest correlation between salinity and polychaete communities. There was the highest correlation between salinity and polychaete communities at both Sinsi-do and Wi-do tidal flat.] This study revealed regional differences in the distribution, biodiversity, and community structure of polychaete worms along the salinity gradient from the Geum River tidal flat to Seocheon coast, Sinsi-do, and Wi-do tidal flats. 본 연구는 새만금호의 방류수에 영향을 받는 신시도, 위도의 조간대와 금강하구의 영향을 받는 금강하구 조간대의 저서 다모류 군집을 비교 분석하기 위해 수행되었다. 위도 조간대에서는 2023년 3월부터 2023년 10월까지 2개 정점에서 계절별 저서생물 조사를 실시하였고, 금강하구와 신시도 조간대에서는 2023년 4월부터 2024년 1월까지 각각 3개 정점에서 계절별 저서 다모류 조사를 실시하였다. 저서 다모류와 퇴적물 시료는 캔 코어를 이용하여 채취하였다. 해수 수온, 염분, 입자크기, 퇴적물 TOC, Chl-a 등의 저서생물 서식 조건을 조사하였다. 평균 염분은 금강하구 갯벌에서 24.4 psu를, 신시도와 위도 갯벌에서 각각 30.4 psu와 32.8 psu까지 거리에 따라 정점 간 염분 차이가 뚜렸하게 나타났다. 위도 갯벌에서 26종의 다모류가 확인되었으며, 금강 인근보다 해안 갯벌에서 더 다양한 다모류 종이 서식하였다. 다모류 우점종 조성은 금강하구 갯벌에서 채집된 주요 우점종은 Hediste japonica 한종이었고, 새만금호의 방류에 영향을 받는 신시도 갯벌의 우점 다모류는 Cirriformia tentaculata, Heteromastus koreanus, H. japonica였고, 외해에 위치한 위도 갯벌의 우점종은 Scoloplos armiger, H. koreanus, Aricidea pacifica, Glycera nicobarica, Pseudopolydora antennata 등이었다. 금강하구와 신시도 갯벌에서 H. japonica가 출현한 것은 신시도 갯벌이 새만금호에서 신시도로 방류되는 담수 유출의 영향을 받고 있음을 시사한다. 다모류 군집의 기능군의 하나인 섭식조합의 조성을 보면 신시도와 위도에서는 BMX (burrowing, motile, non-jawed), SDT (surface deposit-feeding, discrete motile, tentaculate) 등이 우점하였으나, 금강에서는 SMJ (surface deposit-feeding, motile, jawed)가 가장 우세한 섭식조합이었다. 금강하구는 세 지역 중 가장 담수의 영향을 많이 받는 지역으로 유기물함량과 TOC에 다모류 군집이 가장 영향을 받는다. 신시도와 위도는 도서 지역으로서 염분이 다모류 군집과 가장 상관관계가 높았다. 본 연구에서는 금강, 서천, 신시도, 위도로 감에 따른 염분 구배에 따른 저서 다모류의 분포, 생물 다양성 및 군집구조에 지역적 차이를 확인하였고, 이 결과는 향후 하구 환경에 반응하는 다모류 군집에 대한 기본정보 제공에 기여할 것이다.

조직의 ITA/EA 기능이 IT 거버넌스에 미치는 영향

강재화 國民大學校 비즈니스IT專門大學院 2007 국내박사

This research covers the possible influence to IT Governance infrastructure to organization by various effect and function of ITA/EA. Also, provides corroborative verification of differential of influence based on character of organization by effects of ITA/EA. Recently, the government, public organization, Private Corporation, bank and Insurance Company are in preparation to have major informationlization and consider to participate on ITA/EA and IT Governance. With the efforts by government and NIA(National Information society Agency), the concept of ITA/EA has been in the thesis stage but in the result of research shows that 33.6% of total is planning to adopt the ITA/EA, 68.1% of total are in 1-2 stages to recognition and form of formation, and 22.7% are in 3 stages to developing stage. As it indicated total of 90% are either in developing stage or recognition stage. Also for the consideration of IT governance, it's not even in forming stage of getting a concept. Due to the lack of execution on research of ITA/EA, developed the research variable by using all the capabilities and effects from domestic and international references to come up with 24 categories and to tie up to four (4) major sections. Also with various lead on definition and field of IT Governance, gather around all the categories from existing research data and organization to put into five (5) major sections to developed the research variable. Therefore, with survey and analysis procession the developed variable determined categories, it regrouped to five (5) kind of ITA/EA's function and three (3) kind of IT Governance. Thus, some of categories came out to be differently than what it predicted originally. However, organically the research was focus on factor analysis, appropriate analysis and reliability analysis of the presented article and the result came out to be exceed the point of reliability, it required continuous research with modified research model. It actually formed to new research model after include regulation variable and add new variable to the topic. After the verified result on new research model, it indicated the adequate statistical point led to function of ITA/EA could apply the affection to IT Governance. Therefore, when ITA/EA needs to be measured, it arranged in order of importance of IT integration, Infrastructure systemization, IT alignment, improvement on effective use of resource and efficiency of investment. With this sequence, the influence are effecting to IT Governance. When the concept of IT Governance is limiting and effecting by function of ITA/EA, the arrange of importance are management of IT resource & result, management of IT project, and management of IT service. Also, the result provides a statistical differential based on the type of organization whether it's a planning type, performance type, and mixed type. This research offers the following results. First, on function of ITA/EA originally arranged with 20 types of specific function, the result of this research developed to five (5) type of positive variable with evolution management of IT resource, Infrastructure systemization, effect of decision-making, improvement on effective use of resource and efficiency of investment. Second, with various lead on definition and field of IT Governance, gather around all the categories from existing research data and organization to have three (3) types at the result of this research, which are management of IT resource & result, management of IT project, and management of IT service. Third, the research verified the positive answer that focus on ITA/EA could gives infrastructure to establish the IT Governance. Forth, based on business type of organization, the function of ITA/EA has different effects to establish the IT Governance. To summarize the result of this result, the ITA/ EA & IT Governance are very popular in informationalize field and this research is indicating that the successful adoption of ITA/EA will benefits to establish the IT Governance. Also, it gives meanings to the territory of function of ITA/EA and IT Governance that were developed based on environment of domestic market. But the this research might has limitation due to the possibility of leave out partial categories from using all the capabilities and effects from domestic and international references and possibility of leave out few other kind of field on character of organization even efforts to cover most of different organization. As it indicated in above, the more organization shall need to adopt the ITA/EA and operating of IT Governance. Then more detailed and research should be achieve based on the reference and experience. Hope this research could bring the foundation to have continuous research on ITA/EA & IT Governance which are the foundation to informationlization. This research covers the possible influence to IT Governance infrastructure to organization by various effect and function of ITA/EA. Also, provides corroborative verification of differential of influence based on character of organization by effects of ITA/EA. Recently, the government, public organization, Private Corporation, bank and Insurance Company are in preparation to have major informationlization and consider to participate on ITA/EA and IT Governance. With the efforts by government and NIA(National Information society Agency), the concept of ITA/EA has been in the thesis stage but in the result of research shows that 33.6% of total is planning to adopt the ITA/EA, 68.1% of total are in 1-2 stages to recognition and form of formation, and 22.7% are in 3 stages to developing stage. As it indicated total of 90% are either in developing stage or recognition stage. Also for the consideration of IT governance, it's not even in forming stage of getting a concept. Due to the lack of execution on research of ITA/EA, developed the research variable by using all the capabilities and effects from domestic and international references to come up with 24 categories and to tie up to four (4) major sections. Also with various lead on definition and field of IT Governance, gather around all the categories from existing research data and organization to put into five (5) major sections to developed the research variable. Therefore, with survey and analysis procession the developed variable determined categories, it regrouped to five (5) kind of ITA/EA's function and three (3) kind of IT Governance. Thus, some of categories came out to be differently than what it predicted originally. However, organically the research was focus on factor analysis, appropriate analysis and reliability analysis of the presented article and the result came out to be exceed the point of reliability, it required continuous research with modified research model. It actually formed to new research model after include regulation variable and add new variable to the topic. After the verified result on new research model, it indicated the adequate statistical point led to function of ITA/EA could apply the affection to IT Governance. Therefore, when ITA/EA needs to be measured, it arranged in order of importance of IT integration, Infrastructure systemization, IT alignment, improvement on effective use of resource and efficiency of investment. With this sequence, the influence are effecting to IT Governance. When the concept of IT Governance is limiting and effecting by function of ITA/EA, the arrange of importance are management of IT resource & result, management of IT project, and management of IT service. Also, the result provides a statistical differential based on the type of organization whether it's a planning type, performance type, and mixed type. This research offers the following results. First, on function of ITA/EA originally arranged with 20 types of specific function, the result of this research developed to five (5) type of positive variable with evolution management of IT resource, Infrastructure systemization, effect of decision-making, improvement on effective use of resource and efficiency of investment. Second, with various lead on definition and field of IT Governance, gather around all the categories from existing research data and organization to have three (3) types at the result of this research, which are management of IT resource & result, management of IT project, and management of IT service. Third, the research verified the positive answer that focus on ITA/EA could gives infrastructure to establish the IT Governance. Forth, based on business type of organization, the function of ITA/EA has different effects to establish the IT Governance. To summarize the result of this result, the ITA/ EA & IT Governance are very popular in informationalize field and this research is indicating that the successful adoption of ITA/EA will benefits to establish the IT Governance. Also, it gives meanings to the territory of function of ITA/EA and IT Governance that were developed based on environment of domestic market. But the this research might has limitation due to the possibility of leave out partial categories from using all the capabilities and effects from domestic and international references and possibility of leave out few other kind of field on character of organization even efforts to cover most of different organization. As it indicated in above, the more organization shall need to adopt the ITA/EA and operating of IT Governance. Then more detailed and research should be achieve based on the reference and experience. Hope this research could bring the foundation to have continuous research on ITA/EA & IT Governance which are the foundation to informationlization.

선박감속기용 헬리컬 코니칼 기어의 백래쉬와 물림에 관한 연구

강재화 경상대학교 대학원 2011 국내석사

Korea is the best country for ship-building. But nowadays, the speedboat and yacht are not mostly developed yet. For the sleek lines of ship, more innovative transmission system should be obtained in the ship industry. In general, marine transmissions often use the straight shafts and the helical gears. So it makes problem that engine-room requires large space. In this case, conical gear is the best solution for this. Conical involute gear or beveloid gear is very useful in machine design part. But it had not been using until several years ago, because there are some weak points, such as point contact phenomenon of tooth bearing at crossed axes and skewed axes except for parallel axes theoretically, and limited tooth width in terms of addendum modification coefficient which change along the axis of gear. However, conical involute gear is rising as new gear technology. AUDI has already used conical gear in passenger's car gearbox which is called S-tronic to transfer power from transmission's output shaft to front axle and ZF makes Down Angle Transmission for marine gearbox. They not only show conical involute gear can be applied to commercial gearbox recently, but also know that conical gear is very useful and has many attractive applications. In conclusion, until now, this technology is not generalized, but it will be increased more through many applications. So, in order to get conical gear design technology by ourselves, this thesis is conducted. As preciously stated, this paper was written to gain useful information of marine gearbox design applied conical gear through the measurement of backlash, computer analysis and tooth contact test of helical conical involute gear pairs.