유한요소법을 이용한 마이크로 평엔드밀링에서의 공구변형 예측

임정수,조희주,서태일,Lim, Jeong-Su,Cho, Hee-Ju,Seo, Tae-Il 한국생산제조학회 2010 한국생산제조학회지 Vol.25 No.6

The main purpose of this study strongly concerned micro machining error estimation by using FEM analysis of tool deflection shapes in micro flat end-milling process. For the precision micro flat end-milling process, analysis of micro cutting errors is mandatory. In general, tool deflection is a major factor which causes cutting error and limits realization of the high-precision cutting process. Especially, in micro end-milling process, micro tool deflection generates very serious problems in contrast to macro tool deflection. Methods which deal with compensation of cutting error by tool deflection in macro end-milling process have been studied plentifully but, few researches transact with micro scaled cutting tool deflection in micro cutting process. Therefore, the trend of micro tool deflection was estimated by using FEM analysis in this paper. Cutting forces were acquired by micro dynamometer and these were utilized in FEM analysis. In order to verify FEM analysis results, micro machining processes were carried out and real machined profiles were compared with FEM results. Finally through the proposed approach well suited FEM results were obtained.

만성 염증시 치주 결체조직 세포 성장 및 총 단백질 변화에 관한 연구

임정수,오귀옥,김형섭,Lim, Jeong-Su,Oh, Kwi-Ok,Kim, Hyung-Sup 대한치주과학회 1993 Journal of Periodontal & Implant Science Vol.23 No.1

The investigation was undertaken to determin the altered function and structure of granulation tissue fibroblasts. Human granulation-tissue fibroblasts were cultured from periodontal chronic inflammatory lesions (SBI index : above 3) and compared with healthy gingival connective tissues fibroblasts a control(SBI index : below 1). Granulation tissue fibroblasts proliferated with a slower growth rate and exhibited larger cell size than control cells. Total protein profile of granulation tissue fibroblasts was almost identical to that of control cells with some exception. These results support tha theory that granulation tissue fibroblasts represent a distinct phenotype of fibrotic cells.

유아교사의 일터영성 척도 개발

임정수(Jeong-Su LIM),심은주(Eun-Joo SIM),이경화(Kyeong-Hwa LEE) 한국수산해양교육학회 2014 水産海洋敎育硏究 Vol.26 No.4

유한요소법을 이용한 마이크로 평엔드밀링에서의 공구변형 예측

임정수(Jeong-su Lim),조희주(Hee-ju Cho),서태일(Tae-il Seo) 한국생산제조학회 2010 한국생산제조학회지 Vol.19 No.4

The main purpose of this study strongly concerned micro machining error estimation by using FEM analysis of tool deflection shapes in micro flat end-milling process. For the precision micro flat end-milling process, analysis of micro cutting errors is mandatory. In general, tool deflection is a major factor which causes cutting error and limits realization of the high-precision cutting process. Especially, in micro end-milling process, micro tool deflection generates very serious problems in contrast to macro tool deflection. Methods which deal with compensation of cutting error by tool deflection in macro end-milling process have been studied plentifully but, few researches transact with micro scaled cutting tool deflection in micro cutting process. Therefore, the trend of micro tool deflection was estimated by using FEM analysis in this paper. Cutting forces were acquired by micro dynamometer and these were utilized in FEM analysis. In order to verify FEM analysis results, micro machining processes were carried out and real machined profiles were compared with FEM results. Finally through the proposed approach well suited FEM results were obtained.

다양한 치태조절기구가 타이타늄 임프란트의 표면조도와 형태에 미치는 영향

최승환,임정수,송인택,김형섭,Choi, Seoung-Hwan,Lim, Jeong-Su,Song, In-Taeck,Kim, Hyoug-Seop 대한치주과학회 1998 Journal of Periodontal & Implant Science Vol.28 No.2

The purpose of this' study was to compare surface roughness and morphologic changes after use of various plaque control devices to titanium implant surfaces. The study materials were 6 ITI titanium implants($Bonefit^{(R)}$) and 5 plaque control devices. 6 implants were divided into 6 different groups and instrumented by each plaque control devices as follows. 1) Group I : untreated control 2) Group II : Titanium curette(Titanium $curette^{(R)}$, 3i) 80 vertical/horizontal strokes 3) Group III : Plastic curette($Implacare^{(R)}$, Hu-Friedy) 80 vertical/horizontal strokes 4) Group N : Plastic tip-ultrasonic scaler($Amdent^{(R)}$, Amdent) 160 seconds 5) Group V : Rotating interdental brush($Identobrush^{(R)}$, Identoflex) 160 seconds 6) Group VI : Abrasive rubber cup polisher($Zircate^{(R)}$, Prophy paste, Dentsply) 160 sec-onds. All specimens were prepared for evaluation by surface roughness tester, optical stereomicroscopy(OM) and scanning electron microscopy(SEM). The Ra and Rt mean values of the tested specimens were 1) Group I ($Ra=0.170{\pm}0.007{\mu}m$, $Rt=1.297{\pm}0.016{\mu}m$) 2) Group II ($Ra=0.209{\pm}0.006{\mu}m$, $Rt=1.602{\pm}0.110{\mu}m$) 3) Group III ($Ra=0.179{\pm}0.001{\mu}m$, $Rt=1.429{\pm}0.055{\mu}m$) 4) Group IV ($Ra=0.182{\pm}0.005{\mu}m$, $Rt=1.511{\pm}0.085{\mu}m$) 5) Group V ($Ra=0.301{\pm}0.008{\mu}m$, $Rt=1.882{\pm}0.131{\mu}m$) 6) Group VI ($Ra=0.147{\pm}0.010{\mu}m$, $Rt=1.059{\pm}0.021{\mu}m$) In Ra values, experimental group II, V, VI were statistically significant different when compared with control. OM and SEM observation showed that experimental group III, IV were minimal changes when compared with control and group VI was smoothest among other experimental groups. The results suggested that plastic curette and plastic tip-ultrasonic scaler were predictable devices to titanium implant surface.

청소년의 음란물 이용이 성폭력 가해행동에 미치는 영향 : 가족지지의 조절효과를 중심으로

김재엽,최선아,임정수,Kim, Jae Yop,Choi, Sunah,Lim, Jeong Su 대한가정학회 2021 Human Ecology Research(HER) Vol.59 No.4

The purpose of this study was to identify the impact of pornography use among adolescents on their subsequent violent sexual behavior, and to ascertain the moderating effect of family support. The study was conducted with a sample of 2,087 Korean middle and high-school students. To analyze the data, a descriptive analysis, a correlation analysis, and a Poisson regression were conducted using SPSS 24.0. A Poisson regression was performed because the dependent variable, violent sexual behavior, was measured by the frequency of occurrence, and most responses were distributed at '0', indicating a non-normal distribution. The results indicated that 8.1% of adolescents admitted to having sexually violent experiences over the past year, with a relatively high rate of sexual harassment. Secondly, 53.3% of adolescents had used pornography over the past couple of years, with the highest percentage of use occurring via the Internet. Finally, pornography use among adolescents had a significant and direct impact on their sexually violent behavior, with family support playing a moderating role. This indicated that, for adolescents with a high level of family support, the impact of pornography usage on sexually violent behavior decreased. Based on these results, we discuss practical and policy interventions to prevent sexually violent behavior by adolescents.

기구조작에 따른 순수 타이타늄 표면 변화와 치은 섬유아 세포 부착에 관한 연구

서성찬,송인택,임정수,김형섭,Seo, Sung-Chan,Song, In-Taeck,Lim, Jeong-Su,Kim, Hyung-Seop 대한치주과학회 1999 Journal of Periodontal & Implant Science Vol.29 No.3

This study examined the human fibroblasts cell attachment to commercially pure titanium surface which had been instrumented by 3 types of periodontal instruments. Commercially pure titanium plates were uniformly scaled using plastic, stainless steel, titanium curette. these all experimental groups 65 undirectional strokes with the designated curettes. Alteration of the surfaces due to instrumentation was evaluated by Form Talysurf(R) and reported as Ra value(mean surface roughness). Then other experimental groups were immersed in a cell suspension of human gingival fibroblasts($1{\times}10^5$ cell/ml). After 3 days of culture, cell attachment and morphology was observed by SEM, and attached cell were counted by Hemocytometer. A significant difference in mean Ra value was observed for surface instrumented by metal curette compared to either control surface or surface instrumented by the plastic curette(P<0.01). No stastically significant difference was noted between control surface and those instrumented by the plastic curette. SEM observation showed that cell morphology and attachment to the commercially pure titanium plate was similar appearance on the all experimental groups. Experimental groups instrumented by titanium curette and stainless steel curette were more attached cell number than control group, but experimental group instrumented by plastic curette were similar with control groups(P<0.01). In summary, metal curette produced an significant alteration of the commercially pure titanium surface and more favorable surface topography for cell attachment. Otherwise plastic curette was insignificantly altered the commercially pure titanium surface(P<0.01).

다양한 치은 연하 수복물에 대한 치은 섬유아 세포 부착 연구

이은숙,송인택,임정수,김형섭,Lee, Eun-Suk,Song, In-Taeck,Lim, Jeong-Su,Kim, Hyung-Seop 대한치주과학회 1999 Journal of Periodontal & Implant Science Vol.29 No.3

When mucoperiosteal flaps are positioned and sutured to desirable position, the wound contains several interface between tissues which differ fundamentally in composition & biological reaction. Thus the C-T surface of the flap will, on one hand, oppose another vascularized surface, and on the other, the avascular dental material for example, when root resoptions, fractured root, endodontic perforation, deep root carious lesions were filled with amalgam, glass ionomer, resin etc. Recently, a number of case report described the successful treatment of a subgingival root lesion with restorative material & free gingival graft, open flap surgery, but more objective research was needed . Most of study on restorative materials were concerned for cytotoxicity not for actual healing event on that materials and its influencing factors such as biocompatibility, surface wettability, surface topography . The aim of this in vitro study was to evaluate the effect of amalgam, resin modified glass ionomer, composite resin per se, and their surface roughness on the growth of human gingival fibroblast. The cells were obtained and placed on culture flask and incubated for 3 days with the prepared test materials. Then count the attached cell number with hemocytometer,(n=12) and 2 samples were examined with SEM about attachment cell morphology . Another 4 samples were evaluated on their surface roughness with Talysurf and average surface roughness value(Ra) were obtained. Statistical difference in attached cell number, roughness value were analyzed using ANOVA. The number of attached cell was as follows, for root dentin specimen 16.7${\pm}$4.41, resin modified glass ionomer 14.0${\pm}$4.15, resin 8.13${\pm}$3.63, amalgam 0.72${\pm}$3.33(${\times}10^3$). Between root dentin and resin-modified glass ionomer, no significant difference was observed, but resin, amalgam showed a significant less cell numbers than for root dentin, resin modified glass ionomer cement. SEM examination expressed many cell surface attachment apparatus in root dentin and resin modified glass ionomer specimens. For resin specimen, cell attachment was observed but exposed less appratus. The average surface roughness value are following results. Dentin specimen 0.6972${\pm}$ 0.104, resin modified glass ionomer 0.0822${\pm}$0.009, resin 0.0875${\pm}$0.005, amalgam 4.2145${\pm}$0.985(${\mu}m$). Between root dentin, resin-modified glass ionomer, and resin, no significant difference was observed, but amalgam showed a significant more rough surface than other groups. When evlauated the interrelationship between cell attachment and surface roughness, therefore, there was weak reverse correlation.(pearson correlation : - 0.593) These results suggest that resin modified glass ionomer have the favorable healing potential when used for subgingival restoration. And for relationship between cell attachment and surface characteristics, further investigations were needed.

성인 서혜부 탈장에 대한 무긴장 탈장교정술의 임상경험

강구정(Koo Jeong Kang),임정수(Jung Su Lim),임태진(Tae Jin Lim) 대한외과학회 1999 Annals of Surgical Treatment and Research Vol.57 No.6

담도계 수술에서 담즙의 세균 배양과 예방적 항생제 사용의 임상적 의의

손병호(Byung-Ho Sohn),임정수(Jung-Su Lim),조두희(Du-Hee Jo),강구정(Koo-Jeong Kang),임태진(Tae-Jin Lim) 대한외과학회 1998 Annals of Surgical Treatment and Research Vol.54 No.1