• 한국자동차공학회논문집
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• 제25권1호
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• pp.35-41
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• 2017

The use of engineering plastics in automotive components is increasing with the trend towards improving the car strength and reducing weight. Among the different choices of materials, engineering plastic emerged as the necessary material for achieving lower costs, reduced weight and improved production efficiency. To produce the automotive parts, it is important to predict defect and validation of injection molding prior to design. Injection molding analysis and structural analysis are widely applied as a part of the design process when developing automotive parts. Injection molding analysis, in particular, involves a highly complicated mechanism that requires deep knowledge of polymer properties as well as an analytic approach different from that used for a general isotropic material when the molded material is used as a structural material. This is because the parts made of polymer have pre-stress factors such as intrinsic deformation and residual stress. The most important factors for injection molded plastic products are injection molding condition and cavity design, taking into account ease of molding, mass production and application. Despite optimal injection molding conditions and cavity design, however, glass fiber orientation is critically linked to strength reduction. The application of injection molding and structural coupled analysis provides a low-cost solution for product molding and structural validation, all prior to the actual molding. The purpose of this study involves the validation, pre-study, and solution of defect in injection-molded polymer automotive parts using the simulation software for injection molding and structural coupled analysis. Finally, this thesis provides validation of an injection molding and structural coupled analytic mechanism that can demonstrate the effect of glass fiber orientation on mechanical strength. Design improvement ideas for the injection molded product of PPS (Poly Phenylene Sulfide)+40% glass fiber are also suggested.

• Journal of Chest Surgery
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• 제41권1호
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• pp.116-119
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• 2008

경피적 카테터를 이용한 시술은 선천성 심질환의 진단 및 치료에 폭넓게 이용되고 있다. 이러한 시술과 연관된 합병증은 흔하지 않으며 대부분 끈 문제가 없다. 그러나 드물게 응급 수술이 필요할 정도의 매우 심각한 합병증을 유발할 수 있다. 본 증례는 생후 2주된 선천성 대동맥 판막 협착증 환아에서 경피적 풍선 판막 성형술 중 발생한 우측 총장골 동맥의 파열을 적극적으로 조치하여 성공적으로 손상 혈관의 수술적 치료를 시행하여 좋은 결과를 보여 문헌 고찰과 함께 보고하는 바이다.

• 대한방사선기술학회지:방사선기술과학
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• 제45권4호
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• pp.305-312
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• 2022

The proportion and testing of portable radiation tests, which are limited at the request of the doctor, are gradually increasing only for patients in emergency situations and difficulties in moving. However, as there are many limiting factors compared to fixed devices, this study intends to measure and analyze the distortion of images according to the angle of the detector and the change in dose according to the position of the subject. For distortion experiments using a mobile radiation generator used in Hospital A, the SID was tilted by 110 cm, 14"×17" wireless FPD detector to 0°, -5°, -10°, -15°, -20°, and -35° to measure the change in area. The dose according to the location of the detector was analyzed on average by measuring the central dose at 110 cm of the SID and measuring the dose of 9 locations three times each. The analysis result of distortion by location according to the angle of the detector showed a statistically significant difference (f=58.74, p<0.000). Therefore, it can be seen that the angle of the detector and the tube is closely related to the distortion of the image. The difference in dose by location of the detector increased with respect to the center - pole, and decreased with the + pole. Tests using mobile radiation generators will require careful efforts by clinicians to position patients in the center of the detector for accurate diagnosis, and efforts will be made to level the angle between the mobile radiation generators and the detector.

• Genomics & Informatics
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• 제19권4호
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• pp.38.1-38.7
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• 2021

Kawasaki disease (KD) is an acute pediatric vasculitis that affects genetically susceptible infants and children. To identify coding variants that influence susceptibility to KD, we conducted whole exome sequencing of 159 patients with KD and 902 controls, and performed a replication study in an independent 586 cases and 732 controls. We identified five rare coding variants in five genes (FCRLA, PTGER4, IL17F, CARD11, and SIGLEC10) associated with KD (odds ratio [OR], 1.18 to 4.41; p = 0.0027-0.031). We also performed association analysis in 26 KD patients with coronary artery aneurysms (CAAs; diameter > 5 mm) and 124 patients without CAAs (diameter < 3 mm), and identified another five rare coding variants in five genes (FGFR4, IL31RA, FNDC1, MMP8, and FOXN1), which may be associated with CAA (OR, 3.89 to 37.3; p = 0.0058- 0.0261). These results provide insights into new candidate genes and genetic variants potentially involved in the development of KD and CAA.

• 한국산림과학회지
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• 제88권4호
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• pp.562-567
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• 1999

채취시기에 따른 황칠나무 잎중의 화학성분의 변화를 분석한 결과 수분 함량은 계절이 지남에 따라 점점 감소하였으나 지방, 회분 및 섬유 함량은 오히려 점점 증가하였고 단백질 함량은 봄부터 여름까지는 감소하다가 가을에서 겨울로 감에 따라 다시 증가하는 경향을 보였다. 유리당은 검출된 세 종류의 당이 모두 봄으로부터 겨울로 감에 따라 점정 증가하는 것으로 나타났고 지방산은 일반적으로 포화지방산보다 불포화지방산이 더 많이 함유되어 있었으며, 가장 많이 함유된 포화지방산 및 불포화지방산은 계절에 관계없이 각각 arachidic acid 및 cis-13,16-docosadienoic acid였다. 유리 아미노산은 15종이 검출되었는데 계절에 관계없이 arginine의 함량이 가장 높았고 계절이 지남에 따라 점차 감소하는 것으로 나타났다. 무기성분은 채취시기에 따라 그 함량이 약간씩 차이가 있어서 칼슘 또는 칼륨이 가장 많이 함유되어 있었고 다른 무기성분의 함량은 거의 동일한 경향을 보였다. 총 비타민 C 함량은 계절이 점차 겨울로 감에 따라 감소하는 경향이었으나 수용성 탄닌 함량은 오히려 증가하는 경향을 보여 새잎보다 성숙된 겨울에 채취한 잎에 훨씬 더 높은 것으로 밝혀졌다.

• Applied Biological Chemistry
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• 제43권1호
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• pp.63-66
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• 2000

황칠나무 잎과 종실의 일반성분을 분석한 결과 수분은 잎에 70.2%, 종실에 72.6%, 지방은 종실에 0.6%, 잎에 2.7%, 회분은 잎에 1.7%, 종실에 0.9%가 각각 함유된 것으로 분석되었고 단백질은 잎에 1.2%, 종실에 6.2%, 섬유는 잎에 5.1%, 종실에 9.0%가 함유된 것으로 분석되었다. 총 비타민 C는 잎(56.9 mg%)이 종실(10.7 mg%)보다 더 많이 함유하였고 수용성 탄닌함량도 잎(746.1 mg%)이 종실(60.7 mg%)보다 더 높은 것으로 분석되었다. 잎과 종실에 함유된 유리당은 주로 sucrose, glucose 및 fructose로 구성되어 있었으며 종실에는 잎에서 검출되지 않은 turanose와 xylose가 적은 양이지만 검출된 것이 특징이었다. 지방산 조성은 불포화 지방산의 함유율이 더 높았으나 잎과 종실에 가장 많이 함유된 포화 지방산 및 불포화 지방산은 서로 달라 지방산 조성이 약간 차이가 있음을 알 수 있었다. 유리 아미노산 함량은 낮은 편이었고 주요 아미노산은 일과 종실 모두 arginine, aspartic acid, glutamic acid등으로 비슷하였으며, 무기성분은 잎에는 칼슘, 종실에는 칼슘이 가장 많이 함유된 것으로 밝혀졌다.

• 에너지공학
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• 제20권4호
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• pp.346-352
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• 2011

본 연구의 목적은 한국화력발전소에서 사용되는 석탄의 촤 산화반응율을 연구하는 것이다. 석탄촤 산화반응율은 입자의 점화온도에 근거한 Semenov의 열착화이론을 활용하여 도출하였다. 석탄촤의 입자를 열전대를 통해 직접 가열 및 온도 측정을 할 수 있으며, 광각기 센서를 통해 석탄촤점화시 발생되는 빛의 강도를 계측함으로써 점화시점을 결정 할 수 있는 실험장치를 제안 하였다. 아역청탄인 Wira와 역청탄인 Yakutugol의 석탄촤 점화온도는 입자 직경의 변화에 따라 측정을했으며, 입자의 직경이 커질수록 석탄촤 점화온도는 상승하였다. 입자 직경에 따른 석탄촤 점화온도의 결과를 통해 활성화에너지 및 빈도인자를 도출하였다. 본 연구를 통해 도출한 석탄촤 산화반응율 값을 기존의 연구 데이터와 비교한 결과 유사함도 확인할 수 있었다.

• 한국구조물진단유지관리공학회 논문집
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• 제15권2호
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• pp.116-124
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• 2011

본 연구에서는 현재 신교통 수단으로 연구 중인 바이모달 트램의 전용 교량을 개발하는데 있어 바이모달 트램 운행 특성을 고려한 실물크기의 중공화된 프리캐스트 바닥판을 새롭게 설계 제작하여, 신뢰성 있는 비선형 유한요소해석 프로그램(RCAHEST)을 통한 해석 결과와의 비교 분석을 바탕으로 적합성과 타당성을 검증하였다. 하중 재하 위치를 변수로 실험을 수행하여 설계 하중에 비하여 약 8~9배의 충분한 안전율을 확보하고 있음을 확인하였으며, 본 연구에서 적용한 재료적 비선형성을 고려한 비선형 유한요소해석 프로그램을 통한 해석 결과 역시 콘크리트의 균열 발생 및 철근의 항복을 포함한 파괴시까지의 극한 거동 특성을 비교적 적절히 평가하고 있음을 알 수 있다.

• 대한방사선기술학회지:방사선기술과학
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• 제44권5호
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• pp.535-543
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• 2021

The purpose of this study is to investigate various opinions on changes and revisions in the Medical Technician Act, to compare the curriculum of radiological technologist and physicians or dentists, and to compare the definitions and scope of work of radiological technologist in Korea and abroad. From the information, The goal is to review whether the phrase 'guidance of a doctor or dentist' specified in the definition of the 'Act on Medical Technicians, etc.' is realistically appropriate. radiological technologist receive specialized college education on radioligical science & medical imaging. The training hours for radiolgical science student are greater than medical students. In addition, radiological technologists are continuously developing their competencies for new knowledge and skills through continuing education in clinical fields. In particular, radiological technologist are making steady research efforts to reduce patient exposure and improve medical image quality. As a result of this investigation, it is considered that the term "guided by a doctor or dentist" as currently defined in the 'Act on Medical Technicians, etc.' may need to be revised in consideration of the professionalism of the radiological technologist.

• 한국환경과학회지
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• 제16권3호
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• pp.385-392
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• 2007

Currently, portable equipment for recycling of waste asphalt concrete (ASCON) has been used. However, any air pollution control devices are not attached in the simple portable one. Thus, a lot of air pollutants have been produced from recycling processes of waste ASCON which resulted from aging of paved roads or repavement of roads. This study deals with a preliminary result of concentration analysis of air pollutants obtained from a pilot and a real recycling processes of waste ASCON using simple portable recycling equipment. Air pollutants were taken from 4 steps of the pilot recycling process including an initial heating by liquid petroleum gas (LPG), intermediate heating and melting (H&M) process, final H&M process, and pavement processes using recycled ASCON at the recycling site. Also, air pollutants were taken front 4 steps of the real recycling processes including an initial H&M, final H&M and mixing, loading of recycled ASCON to dump trucks, and at the recycling site after leaving the loaded dump trucks for real pavement sites. The air pollutants measured in this study include volatile organic compounds (VOCs), aldehydes, particulate matter (PM: PM1, PM2.5, PM7, PM10, TSP (total suspended particulate)). The identified concentrations of VOCs increased with increasing time or degree for H&M of waste ASCON. In particular, very high concentrations of the VOCs at the status of complete melting, which is exposed to the air, of the waste ASCON just before paving tv the recycled ASCON at the recycling site. Also, considerable amount of VOCs were identified from the recycling equipment after the dump trucks leaded by recycled ASCON leaved the recycling site for the pavement sites. The relative level of formaldehyde exceeded 80% of the aldehydes Identified in the recycling processes. This is because the waste ASCON is exposed to direct flame of LPG during H&M processes. The PM concentrations measured in the winter recycling processes, such as the loading and rotation processes of waste ASCON into/in the recycling equipment for H&M, were much higher than those in the summer ones. In particular, the concentrations of coarse particles such as PM7 and PM10 during the winter recycling were very high as compared those during the summer one.