• 한국분무공학회지
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• 제23권4호
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• pp.212-220
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• 2018

As increase the number of vehicles, the issue of greenhouse gas that was emitted by them became important. As a result, greenhouse gas (GHG) regulations are being strengthened and efforts are being actively made to reduce greenhouse gas emissions in the automotive industry. In the other hand, regulations for harmful emission of vehicles have been reinforced by step. Especially, the lastly applied step, so called Euro 6, not only decreased NOx limit down to half of Euro 5 but also introduced real driving emission limit for NOx and PN. It is a challenge for manufacturers to meet the recent GHG regulation as well as the latest emission regulation. To overcome these regulations a De-NOx after-treatment system is being applied to diesel vehicles that are known emitting the lowest GHG among conventional internal combustion engines. At the time of the introduction of Euro 6 emission standard in Korea, in the domestic fuel economy certification test, some diesel vehicles emitted more $CH_4$ than Euro 5 vehicles. As a result, it was confirmed that LNT-equipped vehicles emitted a high level $CH_4$ and the level exceeded the US emission standard. In order to determine the reason, various prior literature was investigated. However, it was difficult to find a detailed study on the methane increase with LNT. In this paper, to determine whether the characteristics of vehicles equipped with LNT the affects the above issue and other greenhouse gases, 6 passenger cars were tested on several emission test modes and ambient temperatures with a environment chamber chassis dynamometer. 2 cars of these were equipped with LNT only, other 2 cars had SCR only, and LNT + SCR were applied to remaining 2 cars. The test result shown that the vehicles equipped with LNT emitted more $CH_4$ than the vehicles with SCR only. Also, $CH_4$ tended to increase as the higher acceleration of the test mode. However, as the test temperature decreases, $CH_4$ tended to decreased. $CO_2$ was not affected by kinds of De-NOx device but characteristic of the test modes.

• 한국자동차공학회논문집
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• 제24권4호
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• pp.454-462
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• 2016

This study was conducted in order to estimate the exhaust emissions analysis method of the real driving emission(RDE). The Association for Emissions Control by Catalyst(AECC) has developed a test procedure by using a random cycle method based on the chassis dynamometer. In order to confirm this approach in Korea, Euro 5(DPF), Euro 6(DPF + LNT), and Euro 6(DPF + SCR) were performed on three different vehicles to determine the exhaust gas characteristics of the random cycle, real-road driving test(PEMS), and emission certification driving mode(NEDC). Six different random cycle driving modes were generated by the vehicle specifications(e.g. curb weight, engine power, gear ratio, and maximum acceleration). The NOx emissions were increased in the NEDC, random cycle, and PEMS order in this study regardless of the test vehicles. The random cycle method has the advantage because it utilizes a chassis dynamometer in the laboratories for a repeatable data collection, and it allows any eminent emission improvement checked prior to a real-road driving test with PEMS.

• 한국분무공학회지
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• 제25권1호
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• pp.27-33
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• 2020

NOx, PN and CO emissions from diesel trucks make up a significant portion of domestic air pollutant emissions. Therefore, test vehicles with various emission standards and driving modes were selected to evaluate the emission characteristics of regulated pollutants (NOx, PN, CO) in medium-duty trucks. As a result of test, all test vehicles were satisfied with Euro 5 or 6 regulation. NOx emissions of Euro 6 vehicles with after-treatment of LNT + DPF were lower than those of Euro 5 vehicles with DPF. In WLTC mode, all vehicles have high NOx emissions at section of extra high speeds, which are determined by increased fuel consumption and high combustion temperatures. CO and PN emissions from all vehicles were found to be low at section of low speeds. Also, The NO₂/NOx ratio was analyzed at 7-23% in each mode, and the NO₂/NOx ratio increased as the average vehicle speed increased. In NIER 9 mode, the CO, HC, and PN emissions were higher under cold conditions of engine than hot conditions of engine. In addition, vehicles with after-treatment system of LNT have similar NOx emissions level in this study.

• 한국건축시공학회지
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• 제18권6호
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• pp.577-584
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• 2018

본 논문은 합성수지 거푸집 성능평가를 위해 길이 변화율, 충격시험, 소음테스트를 실시하였다. 또한 현장 적용을 통해 합성수지 거푸집 시공성에 대해 검토하였다. 실험결과, 가열 길이 변화 시험, 충격시험은 KS기준치를 모두 만족하는 것으로 나타났다. 소음 테스트의 경우 유로폼이 평균 106dB(A)을 나타냈으며, 합성수지 거푸집은 평균 100.4dB(A)을 나타났다. 음압레벨의 경우, 합성수지 거푸집이 유로폼보다 고주파영역에서 낮게 나타나 시공시 소음 피로도가 적고 주변민원은 감소할 것으로 판단된다. 마지막으로 현장적용결과, 콘크리트 타설 중 거푸집 휨 현상이나 배부름 현상은 발생하지 않았다. 또한 콘크리트 표면 마감도가 합성수지 거푸집이 유로폼면 보다 더 우수한 것으로 나타났다.

• Journal of Chest Surgery
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• 제29권8호
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• pp.816-821
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• 1996

장기이식 수술의 개발과 성공은 신장, 간장, 췌장, 심장 및 폐와 이식을 가능하게 하였으나 공여 장기 의 후송, 장시간 보관의 어려움과 이식 중에 발하는 허혈성 손상에 대한 예방에 많은 문제가 있었다. 현 재까지 폐의 장기 보존에 있어서 그 보존용액에 대해서는 많은 연구가 있었으나 혓태학적 연구가 부족 한 것 같다. 따라서 본 연구의 목적은 기존의 Euro-Collin용액과 University of wisconsin용액의 효과를 시간에 따 른 형태학적 변화와 폐의 수분도의 변화를 관찰함으로써 냉한에 보존된 폐의 변화의 차이를 알아보는데 있다. 방법은 황견을 세 군으로 나누어 보존액을 Group 1(n:5)은 normal saline으로, Group 2(n:5)는 Euro-Collins solution으로, Group )(n:6)는 University of Wisconsin solution등으로 나누어 60시 간까지 냉한에 보존하면서 시간에 따른 형태학적 변화와 폐의 수분율의 변화를 관찰하였다. 결과를 보면 폐의 수분율은 보존 후 6시간부터 증가하여 12시간 후 최대치가 되나,각군 별로는통계 적 인 차이는 없었다. 형 태학적 인 변화로는 제 1군에서 5예 중 1예에서 냉한 보존 1시간 후 자장 먼저 al- veolar septum의 변화를 \ulcorner였고, 2군은 냉한 럴존 6시 간 후부터 5예 중 )예에서 alveolar septum의 distor- tion과 swelling이 있었으며 또 pneumocyte의 변화를 보였고, 3군에서는 6시간 후에는 5예 중 I예에서, 12시간 후에는 5예 중 4예에서 alveolAr septum의 swelling을 보였다. 또 pneumocyte에 대한 변화는 1군 에서는 24시간 후부터, 2군에서는 48신간 후부터, 3군에서는 냉한 보존 60시 간 후에 나타났다 이와 같이 세포의 형태학적 보존은 3군에서 잘 되는 것으로 나타났다.두 군간에 퇴원일자가 P value 0.03으로 의의 있게 흥강경으로 수술한 군에서 짧았다. Group C는 평균연령 45.8세, 수술시간 105분, 통증제거 3.2회, 흥관삽관 6.1일이 었으며 진단율은 81.8 % 였고 group D는 평균연령 53.3세, 수술시간 121분, 통증제거 2.6회, 흥관삽관 10.5일이었으며 진단율 은 100%였다. 수술과 관련된 합병증으로 Group A는 수술중 혈액 량감소성쇽과 심장마비가 각각 1예씩 있었으나 회 복이 되었고수술후농흥과출혈이 각각 1예씩, 일시적 호흡정지 1예, 흉관 7일 이상유지가)예 있었다. Group B에서는 성Til마비와 흥관 7일 이상 유지가 각각 2예씩 있었으며 Horner's 증후군과 brachial neuropathy가 각각 1예씩 있었다. 본 저자들은 비디오 흥강경을 이용한 종격동 종양의 제거를 비교적 안전하게 하였으며 입원기간도 짧 고 수술과 관련된 이병율 및 사망율도 적어 환자를 적절히 선택함으로서 비디오 흥강경수술이 종격동종 괴 절제시 에 좋은 치료방법이라고 사료된다.지수가 유의한 증가를 보였는데 이는 수술 \ulcorner 동반된 폐동맥 성형술등의 영향이 있었음을 감안하여야 할 것으로 생각되었다. 한편 수술전 폐동맥 크기에 대한 지표로서 폐동맥 지수(PAI)와 McGoon 비(MGR)와는 다음과 같은 유의한 상관관계가 있 음을 알 수 있었다 상관식 : PAI : MGRxl18.0-12.4. 결론적으로 양방향성 상대정맥-폐동맥 단락술이 동맥혈내 산소포화도는 증가시키나 폐동맥 지수는 단기간의 본 연구에서는 증가하지 않는 것으로 나타났다. 향후 박동성 양방향성 상대정맥-폐동맥 단락 술이나 또는 Blalock-Taussig 단락술등이 폐동맥의 성 장에 미치는 영 향에 대한 연구가 필요할 것으로 생각된다.0s, in addition to the topics which were interested in before

• 한국분무공학회지
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• 제22권4호
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• pp.218-224
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• 2017

In order to improve the quality of air in urban areas, the emission regulations are being strengthened by the government. The on-road test of light-duty vehicles was started with PEMS because certification test mode does not sufficiently reflect on-road conditions. Therefore, The PEMS-based test was implemented from Sep. 2017 in Europe and Korea. However, this is lack of data on various on-road patterns in Korea. The purpose of the present study has analyzed the effect of speed per acceleration and acceleration on NOx emission on-road driving. The test route consisted of urban, rural, and motorway in Seoul. This study has been conducted by Euro-6 vehicles using on SCR system with PEMS. The on-road emission characteristics were evaluated by moving averaging windows (MAW) method. In results, RDE-NOx by severe driving pattern has been 1.4 times higher than soft driving pattern NIER Route 1.

• 식물병연구
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• 제10권1호
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• pp.25-29
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• 2004

구미시 옥성면 국화 집단재배지에서 국화 생육불량 원인을 조사한 결과, 대부분의 국화(98％)가 뿌리혹선충(Meloidogyne hapla)에 감염되어 있었다. 주요 3품종 중 뿌리에 생긴 난낭의 수는 뿌리 1 g당 'Ardilo' 3.3개, 'Euro' 6.5개, 'Monarisa' 17개로 'Monarisa' 품종에서 난낭 발생이 많았고 'Ardilo' 품종에서 적었다. 국화의 초장, 화경장, 줄기 굵기, 엽수, 착화수, 첫 번째 화수장, 절화중, 엽록소(SPAD), 뿌리무게, 뿌리혹선충의 난낭수 사이의 상관관계를 조사한 결과 난낭수와 엽록소 함량(SPAD) 사이에 부의 상관이 인정되었다(r = -0.418, p = 0.059; r = -0.463, p=0.040). 식물 생육은 키가 크고 화경장이 길수록 꽃수, 잎수가 많고 꽃 무게도 무거웠다(p < 0.05).

• 자동차안전학회지
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• 제8권1호
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• pp.31-37
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• 2016

The Child Occupant Safety Assessment was first introduced and carried out by Euro NCAP in 2003, with the goal of ensuring manufacturers to develop safe vehicles for passengers of all ages; the objective was to evaluate the safety and protection offered by different Child Restraint Systems (CRS) in the event of a crash. In 2013, the formerly used P child dummy series was replaced by newer and more biofidelic Q1.5 and Q3 child dummies, representing 1.5 and 3 year old children respectively. The frontal and side impact dynamic performances of the Q1.5 and Q3 were tested within all classes of vehicles assessed by Euro NCAP at the time. As an extension to that initiative, Q6 and Q10 child dummies were later developed representing children of 6 and 10 years old. Since the protection of larger children during vehicle crashes relies greatly on the interaction of vehicle restraint systems such as seat belt and the CRS, instrumented Q6 and Q10 dummies will be used to assess the protection offered in the event of front and side impact crashes. In this paper, we focused on injury criteria of Q6 and Q10 child dummies at 64 kph 40% offset frontal crash test. The whole procedure was designed with DFSS analysis. The full vehicle sled test results of both dummies were conducted with different restraint systems settled through previous sled test. It showed that several injury criteria and image data were collected as the result of the full vehicle sled test. Based on the results of these investigations, this paper describes which factor is most important and combination shows the best performance when evaluating rear seat occupant protection for Q6 and Q10 child dummies.

• 한국철도학회논문집
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• 제10권6호
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• pp.633-639
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• 2007

본 연구에서는 RFID 기술을 적용하여 이동하는 철도 화차를 인식하는 최적의 조건을 도출하였다. 이동하는 철도 화차를 인식하기 위해서는 주파수 대역의 선정, 안테나의 각도, 이동하는 속도, 태그의 부착위치 등의 고려해야할 요소들이 있다. 그래서 이동하는 철도 화차를 최적으로 인식하는 조건을 도출하기 위하여 주파수 대역은 900MHz/2.45GHz대역을, 안테나의 각도를 0, 30, 45, $60^{\circ}$로, 이동속도 10/30/50km로, 태그의 부착위치를 3부분으로 나누어 실증 테스트하였다. 그 결과 이동하는 철도 화차를 인식하기 위한 최적의 조건을 실험을 통하여 검증하였다. 따라서 철도물류의 위치인식(Location Detection)과 추적(tracking)을 실시간(Real-time)으로 모니터링 할 수 있으며, 나아가 일반 철도에도 적용하여, EURO-Balis 처럼 철도차량을 검지, 추적 등 철도 신호에 적용될 수 있을 것이다.

• Journal of Chest Surgery
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• 제25권3호
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• pp.220-231
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• 1992

We have performed 28 single lung transplantation in mongrel dogs transplanting the left lung exclusively from November 1989 to September 1991, in the department of thoracic surgery of Seoul National University Hospital. In the donor dogs, the main pulmonary artery was divided proximal to its bifurcation, and the left atrium was incised freeing the left veins with a generous atrial cuff. We used cold saline in the first 7 transplantations and Euro-Collins or modified Euro-Collins solution in the remaining 17 transplantations as a lung preservatives. The bronchus was divided at two cartilage rings proximal to the upper lobe bronchus take off. In the recipient procedure, we used a Fogarty catheter as a bronchus block. Left atrial anastomosis was performed first using 5-O prolene and the pulmonary artery was anastomosed using 6-O prolene. The bronchus was anastomosed next with 4-O vicryl interruptedly and covered with a greater omentum which had been prepared previously. All dogs received cyclosporin A and azathioprine as immunosuppressants and were divided into two group. In the 10 Group I dogs, they survived within 6 days, mean survival time was 66.8$\pm$53.4 hours. In remainder 14 Group lI dogs, they survived above 6 days, mean survival time was 9. 5$\pm$5.6 days. The cause of death were as follows: 2 cases of sacrifice, 2 cases of respiratory insufficiency during operation, 2 cases of arrhythmia immediate postoperatively, 2 cases of bleeding, others in Group I, and 6 cases of sacrifice, 4 cases of sepsis, 3 cases of bleeding, others in Group lI. Results of bronchoscopic findings were obstruction above 50% in 12 cases of 16 performance cases within 5th day. Early chest radiologic haziness were showed, and total lung perfusion defect was frequently showed in both group within 7th day. Main autopsy findings were left atrial and pulmonary arterial thrombi and bronchial obstruction The major histologic findings of Group I were pleural exudate, hemorrhagic infarct, pulmonary congestion, and interesting histologic findings of Group II were 3 cases of perivascular or peribronchial lymphocyte infiltration, 3 cases of hemorrhage infarct, 2 cases of interstitial pneumonitis. The structual change of bronchioles, suggesting bronchiolitis obliterans was not observed due to improper preparation of proximal pulmonary tissue and short term survival times.