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이승환 ( Seung Hwan Lee ),천정미 ( Jung Mi Cheon ),정부영 ( Boo Young Jeong ),김한도 ( Han Do Kim ),천제환 ( Jae Hwan Chun ) 한국접착및계면학회 2015 접착 및 계면 Vol.16 No.4
본 연구에서는 수분산 폴리우레탄 아크릴레이트의 접착력 및 물성을 향상시키기 위하여 polyester polyol, 4,4-dicyclohexylmethane diisocyanate (H12MDI), dimethylol propionic acid (DMPA), acrylate monomer를 사용하여 수분산 폴리우레탄 아크릴레이트를 합성하였다. 또한 합성된 수분산 폴리우레탄 아크릴레이트의 물성은 FT-IR, 입도분석, UTM, 접착력 등을 평가하였다. 입도 분석에서 아크릴산의 함량이 증가함에 따라 입자의 크기가 증가하였고, 기계적 물성을 평가한 결과, 아크릴산의 함량이 증가함에 따라 인장강도는 증가하였고 신율은 감소하였다. 접착강도는 PU/acryl 비율 중 acryl의 함량이 증가, 아크릴산의 함량이 증가할수록 증가하였다. 아크릴산의 함량이 0.5 wt%일 때가장 높은 접착강도를 나타내었다. In this study, waterborne polyurethane acrylate were synthesized with polyester polyol, 4,4-dicyclohexylmethane diisocyanate (H12MDI), dimethylol propionic acid (DMPA), acrylate monomer to improve the properties and peel strength. In addition, the properties of the synthesized waterborne polyurethane acylate was evaluated through FT-IR, particle size analysis, UTM, peel strength. As the acrylic acid content increased, particle size increased. In the results of mechanical properties, when the acrylic acid contents increased, tensile strength was increased but elongation was decreased. All peel strength was improved as the acrylic acid contents of WPUA and acrylate ratio of PU/acrylate increased. Optimum peel strength obtained when acrylic acid was 0.5 wt%.
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정명숙 ( Myung Sook Jeong ),천정미 ( Jung Mi Chun ),김경아 ( Kyung Ah Kim ),고선영 ( Sun Young Ko ),이연경 ( Yeon Kyung Lee ),한병희 ( Byoung Hee Han ),신손문 ( Son Moon Shin ) 대한주산의학회 2005 Perinatology Vol.16 No.2
목적: 주산기 뇌경색은 신생아 신경계 질환의 중요한 원인으로 특히 신생아 경련을 보이는 환아의 10~20%에 이르며 출생아 4,000명당 1명 정도로 알려져 있으나 이에 대한 국내에서의 보고가 없어 저자들은 본 연구를 통하여 주산기 뇌경색의 원인, 증상, 방사선적 소견, 경과, 예후를 알아보고자 하였다. 방법: 2000년 1월부터 2004년 5월까지 주산기 뇌경색으로 신생아 집중치료실에 입원한 환아 8예를 대상으로 후향적으로 의무기록을 검토하여 원인, 증상, 병변 부위, 방사선적 소견, 임상경과를 살펴보았고 외래 추적 관찰시의 신경학적 검사와 발달 검사(BSID-II)를 통해 신경학적 발달 및 예후를 평가하였다. 결과: 주산기 뇌경색 환아 8예 중 만삭아가 6예, 미숙아가 2예였으며 성비는 남아가 5예 여아가 3예였다. 이들 중 초기 임상증상은 5예에서 신생아 경련, 3예에서 무호흡 및 호흡 곤란 증상이었으며 생후 2~6일에 시행한 초기 뇌초음파 검사상 전례에서 뇌경색을 의심하였고 이후 전산화 단층촬영, 자기공명 영상검사로 확진하였다. 뇌파검사상 4예에서 이상소견이 관찰되었으며 이상파의 출현이 병변 부위와 일치하였다. 주산기 뇌경색의 원인을 밝히기 위한 혈액 응고 인자 등 혈액검사와 태반조직 검사상 이상 소견을 보인 경우는 없었고 병변 부위는 좌측 반구가 총 8예 중 5예(63%), 우측 반구는 3예(37%)였으며, 좌중대뇌동맥이 8예 중 4예, 좌전중대뇌동맥 1예, 우중대뇌동맥 2예, 우후대뇌동맥 1예였다. 추적 관찰 기간은 3~42개월로 평균 17개월이었으며 외래 추적 관찰이 가능하였던 7예 중 신경학적 증상으로 경한 편측 부전마비가 3예, 간질이 1예 있었고 발달평가는 4예에서 시행하였는데 모두 정상 소견을 보였다. 결론: 주산기 뇌경색의 초기 임상증상으로 경련이 매우 중요하며 초기 진단방법으로 뇌 초음파 검사가 유용하였다. 신경학적 검사상 경한 편측 부전마비와 간질이 환아들의 절반에서 관찰되었으며 향후보다 많은 환아 들을 대상으로 학령기까지의 추적 관찰을 통한 장기간의 전향적 연구가 필요할 것으로 생각된다. Objective: Perinatal infarcts are an important cause of neonatal neurologic morbidity accounting up to 10~20% of neonatal seizures and annual incidence rate is about one in 4,000 live births. The purpose of this study is to describe the clinical presentation, course, radiologic and Electroencephlogram (EEG) findings and to evaluate the neurologic outcome of cerebral infarcts. Methods: Between January 2000 to May 2004, 8 of 40,204 delivered newborns (0.02%) were diagnosed as having cerebral infarcts. The clinical presentation, course, radiologic and EEG findings were characterized by retrospective chart review and neurological outcome was evaluated by neurological examination and developmental test (Bayley Scales of Infant Development-II) at out-patient department. Results: There were 5 males and 3 females. Six cases of them were full term, and other 2 cases were near-term neonates. Five cases presented neonatal seizure and 3 presented apnea or respiratory distress. All cases showed abnormal finding in the cranial ultrasonography that was performed immediately after the first symptoms. After then, diagnosis of cerebral infarct was confirmed by computed tomography and magnetic resonance imaging. Abnormal EEG finding was found in the 4 cases and a correlation between the location of these abnormalities and cerebral infarcts existed. The location of infarct was on the left hemisphere in five of the 8 cases and predominantly in the distribution of the middle cerebral artery. 7 cases were followed and the mean duration of follow up was 17 months (range 3~42 months). Neurologic outcome was normal in 3 cases and abnormal in 4 cases. Mild hemiparesis was present in 3 cases and recurrent epilepsy in 1 case. Developmental test was performed in 4 cases, all of them were normal. Conclusion: Neonatal seizure is an important presentation as the first sign of perinatal infarcts and cranial ultrasound can be used for initial evaluation of these perinatal infarcts. Neuological sequelae remains over half of the patients. Performing long term follow-up study of large cohort study is needed.
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1,5-펜타메틸렌 디이소시아네이트를 이용한 바이오 기반 수분산 폴리우레탄의 합성 및 특성 연구
이도혁(Do Hyeok Lee),천정미(Jungmi Cheon),정부영(Boo Young Jeong),박소영(So-Young Park),천제환(Jae hwan Chun),이원기(Won-Ki Lee) 한국고분자학회 2020 폴리머 Vol.44 No.3
바이오 기반의 isosorbide carbonate diol과 1,5-pentamethylene diisocyanate를 함께 이용하거나 1,5-pentamethylene diisocyanate만을 적용시킨 환경친화적인 폴리우레탄 접착제(WPIP)를 제조하였다. 사슬 연장제인 ethylene diamine(EDA)의 함량에 따라 WPIP를 제조하였고, FTIR과 ¹H NMR을 사용하여 WPIP의 합성을 확인하였다. 또한 DSC와 TGA를 통해 열적 특성인 유리전이온도 및 열분해 온도가 EDA의 함량이 높아질수록 향상되는 것을 확인하였고, UTM을 사용하여 WPIP의 접착 및 기계적 특성을 평가한 결과, prepolymer의 ratio of NCO/OH가 1.3일 때 접착 및 인장 강도가 가장 우수하였다. A new eco-friendly biopolyurethane adhesives (WPIP) were prepared by using bio-based isosorbide carbonate diol, 1,5-pentamethylene diisocyanate or 1,5-pentamethylene diisocyanate. WPIP was manufactured according to the content of ethlyene diamine (EDA) as the chain extender, and synthesized WPIP was confirmed by using FTIR and ¹H NMR. Through DSC and TGA, it was confirmed that the thermal properties such as glass transition temperature and thermal decomposition temperature were improved as the content of EDA was increased. Mechanical and adhesive properties were evaluated by UTM. When the ratio of NCO/OH of prepolymer was 1.3, tensile and adhesive strength were the best.
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기후변화협약 체결에 따른 인천공항 대응방안에 관한 연구
신태섭 ( Tae Sub Shin ),천정이 ( Jeong Lee Chun ),심윤태 ( Yoon Tae Sim ) 한국항공경영학회 2011 한국항공경영학회 춘계학술대회 Vol.2011 No.-
World community adopted UNFCCC in 1992, which recognized the urgency of extending effects in environment and economy caused from global warming. It is predicted that carbon emission in greenhouse gas and mandatory-duty measures would continuously increase. And it is highly probable that Korea would be included in the category of mandatory-duty implementional nations from 2013. From now on since IIAC(Incheon International Airport Corporation) might be included in the technical research of gas reduction and statistic structure in the avition field, which could impact air industry and national economy. Hence air corporations should build the cooperational system to lessen the emission level among agencies involved (government, airport operator, airline corporations). The measures are necessary to reduce the gas emissions by ground vehicles and equipments in airport areas. In addition multiple research and counter-measures also are required to decrease the amounts of gas emissions caused from all kinds of transportations such as visiting cars, public vehicles and staff cars.
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정부영 ( Boo Young Jeong ),천정미 ( Jung Mi Cheon ),이상진 ( Sang Jin Lee ),문진복 ( Jin Bok Moon ),천제환 ( Jae Hwan Chun ) 한국접착및계면학회 2013 접착 및 계면 Vol.14 No.3
본 연구에서는 신발에 사용되는 고무부품의 접착에 있어서 버핑 및 용매 세척 등의 표면처리 공정을 대체하기 위하여, 플라즈마 처리를 통한 표면 및 접착특성을 알아보았다. 플라즈마 처리 시분사노즐과 고무 시편과의 거리가 감소할수록 접촉각은 감소하였으며, 플라즈마 처리속도가 증가함에 따라 접촉각은 증가하였다. 고무 시편의 표면조도 측정결과 플라즈마 처리 후 Ra 값은 20%, Rz 값은 16%가 증가하는 결과를 나타내었다. 플라즈마 발생 노즐과 고무시편과의 거리가 증가함에 따라 접착력은 감소하고, 플라즈마 처리속도가 증가함에 따라 접착력은 감소하였다. In this study, we studied surface and adhesion properties with plasma treatment for substitution of buffing and solvent-cleaning in footwear adhesion process. The distance between nozzle and rubber parts was decreased with decreasing the contact angle. And when a speed of plasma treatment increased, the contact angle increased. The result of surface roughness, Ra and Rz increased in 20% and 16% after the plasma treatment. The distance of between nozzle and rubber parts was decreased with decreasing the peel strength. And the speed of plasma treatment was increased with decreasing the peel strength.
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미국의 대테러 항공보안 전략에서 얻은 시사점 연구 -미국 TSA 점검대비 및 항공보안 계획 보완-
신태섭 ( Tae Sub Shin ),천정이 ( Jeong Lee Chun ) 한국항공경영학회 2011 한국항공경영학회 추계학술대회 Vol.2011 No.-
9.11 terror attacks by way of simultaneously multiple crash gave a great amount of impacts on U.S. and worldwide community despite the numerous early warnnings by the intelligence agencies before the incidents,which could have been prevented if government had engaged in timely actions and measures. Based on that hard experiences, security and intelligence organizations scattered then were integrated by leading role of the Congress. As a result larger integration turned out a new birth of DHS with 170,000∼180,000 employees(currently 230,000 members) which have the direct control of TSA-fully in charge of aviation security and safety to the air domain. TSA have played key roles in developing the various operational plans according to the avaition strategy and standards. Under above guidence, TSA periodically inspect air operation companies around the world and give penalties unless meet their standards. TSA had analyzed all types of avaition threats and emphasized the strategic actions, which could produce the seven supporting plans including “aviation transportation system security plan” and “response plan” etc. From above suggestions in the plans, Incheon airport have to evaluate the threat assesment as a top priority on the zero-base view point and develop “preparation plans” from that estimations accordingly. Next step would be integration of information flow channel, lastly harmonization of activities carried by government agencies, airport operators, airport-resident establishment and local communities all together. In addition, this research would be helpful for the perfect preparations for TSA` visits to airport simultaneously.
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선도장 컬러강판용 도료에 적용하기 위한 자가 광경화형 폴리우레탄 아크릴레이트 올리고머 합성 및 물성
박소영 ( So-young Park ),천정미 ( Jungmi Cheon ),정부영 ( Boo Young Jeong ),이도혁 ( Do Hyeok Lee ),천제환 ( Jae Hwan Chun ) 한국접착및계면학회 2020 접착 및 계면 Vol.21 No.1
본 연구에서는 Michael addition 반응을 통해 자가 광경화형 중간체를 합성하여 이를 적용한 폴리우레탄 아크릴레이트 올리고머를 합성하였다. 합성된 중간체와 폴리우레탄 아크릴레이트 올리고 머의 분석 및 물성은 FT-IR, NMR 및 UTM을 통해 확인하였다. 중간체의 함량이 증가할수록 인장강도는 증가하고 신율은 감소하였으며 필름이 소수성을 띄어 표면에너지가 감소하는 경향을 보였다. 중간 체의 함량이 40 wt%일 때 부착성, 가공성, 연필경도가 우수했으며, 내용제성은 모두 우수한 결과를 나타내었다. In this study, we synthesized a self-photocuring intermediate(SPI) by Michael addition reaction and synthesized polyurethane acrylate oligomer. Analysis and physical properties of the synthesized SPI and polyurethane acrylate oligomer were confirmed by FT-IR, NMR and UTM. As the content of the SPI increased, the tensile strength increased and the elongation decreased. In addition, since the film was hydrophobic, the surface energy tended to decrease. When the content of the SPI was 40 wt%, adhesion, processability, and pencil hardness were excellent, and solvent resistance was excellent overall.
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