http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
구철인,정재헌,최한철,Koo Cheol-In,Chung Chae-Heon,Choe Han-Cheol 대한치과보철학회 2004 대한치과보철학회지 Vol.42 No.2
Statement of problem: Implant screw loosening has been remained problem in restorative practices. Surface treatment of screw plays a role of preventing screw from loosening in implant screw mechanism. Purpose : The purpose of this study was to investigate surface characteristics of TiN and ZrN film ion plated screw with titanium and gold alloy screw and to evaluate wear resistance, surface roughness, and film adhesion on screw surface using various instruments. Material and methods : GoldTite screws and titanium screws provided by 3i (Implant Innovation, USA) and TorqTite screws or titanium screws by Steri-Oss (Nobel Biocare, USA) and gold screws and titanium screws by AVANA (Osstem Implant, korea) were selected. Ion plating which is much superior to other surface modification techniques was carried out for gold screws and titanium screws using Ti and Zr coating materials with nitrogen gas. Ion nitrided surface of each abutment screw was observed with field emission scanning electron microscopy (FE-SEM, micro-diamond scratch tester, vickers hardness tester, and surface roughness tester. Results : 1) The surface of gold screw and GoldTite is more smooth than ones of other kinds of non coated screw. 2) The ZrN and TiN coated surface is the more smooth than ones of other kinds of screw. 3) The hardness of TiN and ZrN coated surface showed higher than that of non coated surface. 4) The TiN coated titanium screw and ZrN coated gold screw have a good wear resistance and adhesion on the surface. 5) The surface of ZrN coated screw showed low surface roughness compared with the surface of TiN coated screw. Conclusion : It is considered that the TiN and ZrN coated screw which would prevent a screw from loosening can be applicable to implant system and confirmed that TiN and ZrN film act as lubricant on surface of screw due to decrease of friction for recycled tightening and loosening.
구철(Cheol Koo),김미정(Mi Jung Kim),성종호(Jong Ho Sung),안영주(Young Ju Ahn),최성규(Sung Kyu Choi),유종선(Jong Sun Rew),김세종(Sei Jong Kim),윤종만(Chong Mann Yoon) 대한내과학회 1991 대한내과학회지 Vol.41 No.3
N/A To evaluate the colonic transit in patients with irri- table bowel syndrome, the authors measured the colonic transit time with radioopaque markers. The segmental colonic transit time with commercially available radioopaque markers (Sitzmarks) was studied in 28 healthy volunteers and 41 patients with irritable bowel syndrome (19 constipation dominant types and 22 diarrhea dominant types). The subjects ingested capsule (20 radioopaque 0-ring) at 9:00 a.m. on 3 successive days while they were fully ambulatory. A plain radiography of the abdomen was obtained on the 4th day. Using the modified Arhan and Wald method, the colonic transit was assessed. The results were as follows: 1) The total colonic transit was 22.4±4.9 h(Mean SE); segmental transits were 8.7±4.2 h for the right colon, 9.9±4.3 h for the left colon, and 3.9±4.8 h for the rectum in the normal control group. Age and sex did not influence transit significantly, 2) The total colonic transit was 50.8±12.0 h in the constipation group and 2. 5±1.7 h in the diarrhea group, and it was significantly different from that of the nor- mal control group. 3) Comparison between the normal contral group and patients with irritable bowel syndrome revealed that the right colonic transit time ratio significantly decreased in the constipation group, while the left colonic transit time ratio increased in the constipation group and significantly decreased in the diarrhea group, and the rectal transit time ratio significantly increased in the diarrhea group, This study suggests that the left colonic segment may be a major lesion site in irritable bowel syndrome.
류성열 ( Sung Yul Ryoo ),구철도 ( Chul Mo Koo ) 한국지식경영학회 2012 지식경영연구 Vol.13 No.4
Although the role of information systems (IS) on environmental sustainability much attention, the coordination between green practices and environmental management information systems (EMIS) in a firm remains unexplored area in environmental management and IS disciplines. This study elaborated the antecedents of the coordination between green practices and EMIS and then examines the links among them. Also, this study investigated the links from the coordination between green practices and EMIS to firm`s environmental performance. The results showed that both attitudes of managers who are responsible for a firm`s green practices and their support had direct effects on the coordination between green practices and EMIS. Also, consistent with environmental management literature, the study provides a better understanding of the relationship between the coordination between green practices and EMIS and environmental performance.