세라믹-금속 브레이징 접합조인트의 고온 접합강도에 관한 연구

이수정,정명영,이대길,구형회,Lee, Su-Jeong,Jeong, Myung-Yeong,Lee, Dai-Gil,Goo, Hyung-Hoi 대한기계학회 1996 大韓機械學會論文集A Vol.20 No.2

Four point bending tests of the brazed joint composed of sintered silicon nitride and 0.2% carbon steel with Cusil ABA filler which were fabricated at 86$0^{\circ}C$ were performed at temperatures, 25, 100, 200, 300, 400, 50$0^{\circ}C$ From the experiments, the maximum bending strength was measured at 30$0^{\circ}C$ From the 3D FE analysis of the residual stress of the brazed joint, it was revealed that the thermally induced residual stresses were minimized when the environmental temperature was 35$0^{\circ}C$ Considering the degradation of the filler material at high temperatures, it was calculated that the maximum bending strength of the brazed joint occured just below the temperature of the minimum thermal residual stress and the thermal residual stress was the dominative parameter of the brazed joint.

직물의 Drape 특성과 Flare Skirt 의 헴라인 단면 형상

이수정,김연희,홍정민,이송자 ( Su Jeong Lee,Yeon Hee Kim,Jeong Min Hong,Song Ja Lee ) 대한가정학회 1995 Family and Environment Research Vol.33 No.4

수복재료와 내가동연결장치가 IMZ 임프란트 보철물의 충격흡수효과에 미치는 영향

이수정,정찬목,전영찬,Lee, Su-Jeong,Chung, Chan-Mo,Jeon, Young-Chan 대한치과보철학회 1997 대한치과보철학회지 Vol.35 No.1

The purpose of this study was to evaluate the shock absorbing effect of 4 restorative materials and intramobile connector. The damping effect of four restorative materials used to veneer test crown rigidly connected to IMZ implant and subjected to an impact force was measured. These materials included a gold alloy(stabilor G) : a noble metal ceramic alloy(Degudent H) : porcelain(Duceram) : composite resin(Dentacolor). In addition, this study compared damping effect of same restoretive materials after using polyoxymethylene intramobile connector(POM IMC). The result of this study suggest that : In case of using metal IMC 1. Veneered composite resin(group IV) reduced the impact force by 75%, when compared to an equivalent thickness of porcelain(group III). Group IV reduced the impact force by 87% and 89%, respectively, when compared to Stabilor G(group I) and Degudent H(group II). 2. The impact force recorded was higher for the alloy with the higher elastic modulus.(Stabilor G, group I, Young's modulus 107 Gpa, versus Degudent H, Group II, Young's modulus 95 Gpa) 3. It took the longest time for composite resin veneered group(IV) to reach to peak force when compared group I, II, III. In case of using POM IMC 4. The mean impact force recorded were reduced by 79%(group I), 78%(group II), 69%(group III), 84%(group IV), respectively, when compared to using metal IMC. 5. The time required to reach the peak force were increased by 78%(group I, II) 87%(group III), 34%(group IV), respectively, when compared to using metal IMC>.

Nd:YAG 레이저 조사시 치근면에 미치는 효과에 관한 주사전자현미경적 연구

이수정,김수아,서석란,김형섭,Lee, Su-Jeong,Kim, Soo-Ah,Seo, Seok-Ran,Kim, Hyung-Seop 대한치주과학회 1997 Journal of Periodontal & Implant Science Vol.27 No.3

The purpose of this study was to evaluate the in vitro effects of Nd:YAG laser irradiation on removal of a root surface smear layer after root planing in comparison with Tetracycline HCl. The 60 extracted human teeth due to severe periodontal disease were vigorously scaled and root planed with Gracey curet. Thirty specimen($5{\times}5{\times}2mm$) were obtained from root planed surface of 30 human teeth and assigned randomly to one of three groups : root planed group(5 specimen), Tetracycline HCI group(5 specimen, burnished for 5 minutes), and Nd:YAG laser group(25 specimen, German Dental Laser, Fotona Twinlight). Nd:YAG laser group was divided into 4 subgroups according to power of 1W, 1.5W, 2W, 3W at frequency to 10Hz. The specimen were then fixed, and examed by Scanning electron microscopic study. 30 of 60 human teeth used to measurement of the intrapulpal temperature rise during laser irradiation. Laser-irradiated surface exhibited various surface texture from relative flat surface to irregular surface with patent dentinal tubules of various shape and size. In some area, the root surface alteration which are carbonization, pit and crater formation and melting and resolidification were observed. The number of exposed dentinal tubules per unit($100_{\mu}m^2$) on tetracycline HCI group was more than that in the laser group below 1.5W of power(150mJ/pulse) and was significantly less than that in laser group above 2W of power(200mJ/pulse)(P<0.OOl). As power increased the intrapulpal temperature rise also increased. The result suggested that the parameter which effectively remove root surface smear layer than tetracycline HCI may cause thermal damage to pulp and root surface alteration result from laser exposure would indicate need for additional instrumentation. Thus, Nd:YAG laser irradiation in these parameter may not be appropriate for clinical use as adjunct to conventional periodontal therapy.

한반도 남부지역에서 산출되는 카올린광물의 고온영역에서의 광물학적 특성 연구

이수정,문희수,Lee, Su-Jeong,Moon, Hi-Soo 대한자원환경지질학회 1996 자원환경지질 Vol.29 No.3

Dehydroxylation and mullitization of primary and secondary kaolins were investigated in order to compare and understand the differences in thermal behaviours by DTA and TG up to $1,100^{\circ}C$. Chemical analyses and EPMA of the samples revealed nearly ideal unit-cell formulae of kaolins. The weight losses of dickite and halloysite are 14% and 12.5% on the average, respectively. The activation energies of dehydroxylation of kaolin minerals were calculated according to Kissinger's approach which uses various heating rates in DTA to estimate the activation energy of thermal reactions. The activation energies of dehydroxylation of halloysites from Daemoung and Buksam mines are about $163kJmor^{-1}$ (white), $168kJmor^{-1}$ (pink), and $176kJmor^{-1}$ respectively. The activation energies of dickites collected from Sungsan and Ogmae mines are about $166kJmor^{-1}$ and $387kJmor^{-1}$. The asymmetric shape of endothermic peak in DTA, the relative intensities of OH-stretching bands in FTIR spectroscopy and the existence of residual XRD peaks of the samples which were heated at $550^{\circ}C$ for 2 hours indicate that Sungsan dickite may be more disordered than Ogmae dickite. The new phase formed in thermally treated samples in the range of $900^{\circ}C$ to $1,100^{\circ}C$ was identified as mullite by XRD on the basis of disappearing of the characteristic peaks of kaolins and increasing of amorphous background upon heat treatment. On further heating, loss of more water from dehydroxylate resulted in the formation of mullite and the characteristic X-ray diffraction patterns of mullite began to appear at about $900{\sim}1,000^{\circ}C$ in kaolins.

Texture Electron Diffraction Pattern에 의한 결정구조 해석

이수정,주형태,김윤중,문희수,Lee, Su-Jeong,Jou, Hyeong-Tae,Kim, Youn-Joong,Moon, Hi-Soo 한국현미경학회 2002 Applied microscopy Vol.32 No.3

Texture electron diffraction pattern을 이용한 결정구조 해석 이론은 러시아어로 씌여졌거나, 영문판 저서의 일부에 간단히 소개 되어있어 이해에 어려움이 있다. 이들의 이론은 벡터의 이론과 관련된 여러 관계식을 이용해서 설명될 수 있으며, 이로서 몇 개의 식에 포함된 오류를 수정하였다. The works of texture electron diffraction patterns for crystal structure analysis are written in Russian or introduced briefly in books written in English, which makes it difficult to be understood. In addition to working out the equations, vector theory corrects some errors included in the established formulas for texture electron diffraction patterns.

카올리나이트의 상전이반응 과정 연구

이수정,김윤중,문희수 ( Su Jeong Lee,Youn Joong Kim,Hi Soo Moon ) 한국광물학회 1998 광물과 암석 (J.Miner.Soc.Korea) Vol.11 No.1

다이아세틸 (Diacetyl) 이슈의 등장과 미국 산업보건계의 동향-고소한 버터향 뒤에 숨겨진 치명적 폐독성-

이수정,Lee, Su-Jeong 한국산업간호협회 2007 한국산업간호협회지 Vol.14 No.3

세균성 뇌수막염에서 뇌척수액 Latex 응집 추적검사의 유용성

이수정,안소현,조수진,김혜순,이승주,Lee, Soo Jeong,Ahn, So Hyun,Cho, Su Jin,Kim, Hae Soon,Lee, Seung Joo 대한소아청소년과학회 2003 Clinical and Experimental Pediatrics (CEP) Vol.46 No.4

목 적 : 세균성 뇌수막염은 높은 사망률과 후유증을 가져오는 심각한 소아에서의 감염성 질환 중 하나이다. 본 연구에서는 이미 알려진 뇌척수액 latex 응집검사의 진단적 가치 외에도 추적검사에서 예후 예측 인자로서 유용성을 알아보고자 하였다. 방 법 : 1997년 1월부터 2002년 6월까지 세균성 뇌수막염으로 진단받고 이화의대 목동병원에서 입원치료 받았던 25명의 환아들중 뇌척수액 세균배양검사와 latex 응집검사가 모두 양성이었던 19명을 대상으로 하였다. 의무기록에서 임상증상, 뇌척수액 소견, 방사선학적 소견 그리고 신경학적 후유증에 대해 조사하였다. 뇌척수액 추적검사는 항생제 치료 후 3, 7, 14, 21일 그리고 28일에 시행하였고, 3일째 음성이 된 환아들을 I군으로, 3일 이후에도 지속적으로 양성으로 남아있는 환아들을 II군으로 나누었다. 결 과 : 대상 환아 19명의 평균 나이는 $10.6{\pm}12.3$개월(2-33개월)이었고, 원인균으로는 H. influenzae type b 11명(57.9%), Group B Streptococcus 4명(21.1%), S. pneumoniae 3명(15.7%), 그리고 E. coli 1명(5.3%)이였다. I군은 10명(52.6%), II군은 9명(47.4%)이였다. 뇌척수액 추적검사에서 세균배양검사는 3일째 모두 음성화되었고, latex 응집 추적검사는 3일째 9명(47.4%)에서 양성이었고, 7일째 31.6%, 14일째 26.3%, 21일째 10.5%에서 양성이었고, 28일째에 모두 음성이 되었다. I군에서는 2명(20.0%)에서 경막하삼출 소견을 보였다. II군에서는 9명(100.0%) 모두에서 경막하 삼출을 보였고, 이 중에서 44.4%에서 뇌수종 또는 뇌연화 소견을 보였다. 신경학적 후유증은 II군에서 감각신경성난청 1명, 경련성 질환 1명 그리고 우측반신마비 1명이 발생했고, I군에서는 발생하지 않았다. 결 론 : 세균성 뇌수막염 치료 시 뇌척수액 latex 응집 추적검사를 실시하는 것은 치료 초기에 신경학적 예후를 예측하는데 유용하였다. Purpose : Bacterial meningitis is a serious infection of childhood associated with a significant morbidity and mortality. Repeated cerebrospinal fluid(CSF) examination is a useful prognostic indicator and a delayed sterilization is associated with a higher incidence of neurologic abnormalities. In this study we tried to determine the prognostic value of repeated CSF latex agglutination testing. Methods : We retrospectively evaluated 19 patients admitted to Ewha Womans University Mokdong Hospital for bacterial meningitis from January 1997 to June 2002. Bacterial meningitis was confirmed by a positive CSF culture and a positive CSF latex agglutination test. Repeated CSF examinations were done at three, seven, 14, 21 and 28 days after antibiotics therapy. Neuroradiologic studies were performed. Results : The mean age was $10.6{\pm}12.3months$(range; two to 33 months). The male to female ratio was 2.8 : 1. The causative organisms were Haemophilus influenzae type b 57.9%, Group B Streptococcus 21.1%, Streptococcus pneumoniae 15.7% and Escherichia coli 5.3%. Three days after the initiation of antibiotics therapy, repeated CSF latex agglutination tests persisted as positive in nine (47.4%) out of 19 cases, but all CSF cultures became negative. In those cases with negative latex agglutination tests three days after antibiotics therapy, neuroradiologic findings were completely normal. But, in cases with positive latex agglutination tests three days after antibiotics therapy, neuroradiologic abnormalities such as cerebral infarction, encephalomalasia occurred in 44.4%. Conclusion : Repeated CSF latex agglutination testing was valuable as a prognostic factor in bacterial meningitis. Neuroradiologic abnormalities may occur in cases with delayed clearance of CSF latex agglutination tests more often than in cases with negative latex agglutination tests three days after antibiotics therapy.

한의원과 한방병원에서 행해지고 있는 소아에 대한 한약복약지도 현황 조사 연구

이수정,이승연,유선애,Lee, Su Jeong,Lee, Seung Yeon,Yu, Sun Ae 대한한방소아과학회 2013 대한한방소아과학회지 Vol.27 No.3

Objectives Children's unique taste bud often gives them difficult time to take oriental medicines. To overcome, survey was conducted focusing on useful and practical tips on how to take them. Methods The survey was carried out by posting mail questionnaire. Target clinics for the survey were selected by the internet search engine, Google, Daum, and Naver, and typing in "oriental treatment + pediatrics", "pediatrics + oriental medicine", "pediatric oriental clinic". 24 clinics were searched, but they were further narrowed down to the specialized pediatric oriental clinics. Also, total of 38 inquiry leaflets were distributed to 14 University Oriental Hospitals. Results If children refuse to take the medicine, mixture with sweeteners can be prescribed for them. Among them, oligosaccharide is the most recommended followed by sugar and honey. To avoid rejection to medication, use of different formulation, such as distillation medicine, soft X-Section, granulated medicine, and character printing can be used. Conclusions The most effective method is to investigate the mixture first, and then the alternative formulations.