[제9주차 정규강좌] “탄소중립시대, 왜 도시인가?” / “지속가능발전의 의미와 전략”

송재민,김부열 서울대학교 환경대학원 2021 環境論叢 Vol.68 No.-

CDR을 사용한 FPGA 기반 분산 임베디드 시스템의 클록 동기화 구현

송재민,정용배,박영석,Song, Jae-Min,Jung, Yong-Bae,Park, Young-Seak 대한임베디드공학회 2017 대한임베디드공학회논문지 Vol.12 No.4

Time synchronization between distributed embedded systems in the Real Time Locating System (RTLS) based on Time Difference of Arrival (TDOA) is one of the most important factors to consider in system design. Clock jitter error between each system causes many difficulties in maintaining such a time synchronization. In this paper, we implemented a system to synchronize clocks between FPGA based distributed embedded systems using the recovery clock of CDR (clock data recovery) used in high speed serial communication to solve the clock jitter error problem. It is experimentally confirmed that the cumulative time error that occurs when the synchronization is not performed through the synchronization logic using the CDR recovery clock can be completely eliminated.

이미지 인식 기술의 산업 적용 동향 연구

송재민,이새봄,박아름 한국콘텐츠학회 2020 한국콘텐츠학회논문지 Vol.20 No.7

Based on the use cases of image recognition technology, this study looked at how artificial intelligence plays a role in image recognition technology. Through image recognition technology, satellite images can be analyzed with artificial intelligence to reveal the calculation of oil storage tanks in certain countries. And image recognition technology makes it possible for searching images or products similar to images taken or downloaded by users, as well as arranging fruit yields, or detecting plant diseases. Based on deep learning and neural network algorithms, we can recognize people's age, gender, and mood, confirming that image recognition technology is being applied in various industries. In this study, we can look at the use cases of domestic and overseas image recognition technology, as well as see which methods are being applied to the industry. In addition, through this study, the direction of future research was presented, focusing on various successful cases in which image recognition technology was implemented and applied in various industries. At the conclusion, it can be considered that the direction in which domestic image recognition technology should move forward in the future. 본 연구는 이미지 인식기술 서비스의 산업 적용 사례를 기반으로 인공지능이 이미지 인식기술에 어떠한 역할을 하고 있는지 살펴보았다. 이미지 인식 기술을 사용하여 위성사진을 인공지능으로 분석해 특정 국가의 원유 저장탱크의 산출 내역을 밝혀내거나, 사용자가 촬영하거나 다운로드한 이미지와 유사한 이미지나 제품을 검색해주기도 하며, 과일의 산출량을 정렬한다거나 식물의 질병을 탐지해 낼 수도 있다. 딥러닝과 신경망 알고리즘을 기반으로 사람의 나이, 성별, 기분까지도 인식할 수 있어 이미지 인식 기술이 다양한 산업에서 적용되고 있음을 확인하였다. 본 연구에서는 국내 및 해외의 이미지 인식 기술의 활용 사례를 살펴보는 것 뿐 아니라, 어떠한 형태로 산업에 적용되고 있는지 확인을 할 수 있다. 또한, 본 연구를 통하여 여러 산업에서 이미지 인식기술을 구현하고 적용하여 발전시킨 여러 성공 사례들을 중심으로 향후 연구의 방향성을 제시했으며, 향 후 국내 이미지 인식 기술이 나아가야 할 방향을 고찰해 볼 수 있다.

간장의 횡격막 탈장에 의한 Budd-Chiari 증후군: 1예 보고

송재민,윤중원,김재욱,정우경,정희선,김주형,최준호,김승호 대한영상의학회 2007 대한영상의학회지 Vol.56 No.1

Budd-Chiari syndrome is an uncommon disorder, and it is caused by obstruction of the hepatic venous outflow or inferior vena cava above the hepatic vein. It may result from a large number of conditions, including primary congenital obstructions of the hepatic veins or inferior vena cava by webs or bands. Secondary causes include trauma, polycythemia vera, chronic leukemia, pregnancy, tumors and use of oral contraceptives. No definitive etiologic factors have been identified in two thirds of all cases (1-3). We recently experienced a case of Budd-Chiari syndrome caused by diaphragmatic hernia in 21-year-old man. Postoperative follow up CT showed normal venous flow after reintroduction of the liver into the abdominal cavity and closure of the diaphragm defect. Budd-Chiari 증후군은 드문 질환으로서 간정맥 또는 하대정맥의 위치에서 간정맥 유출의 폐쇄를 특징으로 하는 여러 질병을 포함하여 통칭하는 질환이다. 원인으로는 일차성으로 막과 밴드에 의한 선천성 간정맥 유출의 폐쇄와 이차성으로 종양에 의한 간정맥 침범 또는 압박, 외상, 임신, 경구 피임제, 만성백혈병 등을 들 수 있으나 최근에 영상학적 진단의 발달에도 서구에서는 아직도 2/3 정도는 원인 미상으로 보고되고 있다(1-3). 임상증상으로 간비대, 복통, 복수 등이 관찰될 수 있으나 항상 관찰되는 것은 아니며 흔히 비특이적 간문맥압 상승, 황달, 정맥류 출혈을 보일 수 있다(1, 2). 저자들은 최근 간장의 횡격막 탈장에 의한 Budd-Chiari 증후군 1예를 경험하였고 이는 국내외적으로 드물게 보고되고 있어 흉부사진과 전산화단층촬영 소견을 보고하는 바이다.

녹차 카테킨

송재민 한국식품과학회 2008 심포지엄 Vol.2008 No.1

Electrooptical Threshold Behavior of Electroconvection in Twisted Nematic Liquid Crystal Cells

송재민,최규진,곽진석,손영구,허종훈 한국물리학회 2017 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.70 No.3

In this paper, the electrooptical threshold behavior of electroconvection caused by the electrohydrodynamic instability in twisted nematic liquid crystal cells is presented. We observed the electroconvection optically and analyzed the change in the electrical threshold behavior according to the twisted angles in twisted liquid crystal cells in the conduction region that shows the Williams domain, which is one of the most basic patterns for electroconvection in an anisotropic fluid like liquid crystals (LCs). As a result, we confirmed that in the low frequency conduction regio where the Williams domain appears, the threshold voltage decreased as the twist angle increased even though the twist structure enhanced the effective viscosity in liquid flow. The increase in the twist angle may shorten the charge relaxation time because a twisted LC is a structure that more easily accumulates electrical charges on local curvatures.

유경 횡복직근피판술 후 발생한 부분 피판괴사 및 지방괴사의 넓은등근피판을 이용한 재건 치험례

송재민,양정덕,정기호,정호윤,조병채,이상윤 대한성형외과학회 2009 Archives of Plastic Surgery Vol.36 No.1

Purpose: The transverse rectus abdominis musculocutaneous(TRAM) flap is the most commonly used autogenous tissue flap for breast reconstruction. Postoperatively, partial flap loss or fat necrosis are relatively common and it may result in a smaller breast volume with marked contour irregularities. These defects are not easy to reconstruct with local tissue rearrangement or with breast implants. The current authors present the results of 2 patients who underwent Latissimus dorsi(LD) flap reconstruction to correct partial flap or fat necrosis that developed after TRAM flap breast reconstruction. Methods: Case1: A 50-year-old woman with left breast cancer visited for breast reconstruction after radical mastectomy. Initially, breast reconstruction with pedicled TRAM was performed. Postoperatively partial flap necrosis was developed. Secondary breast reconstruction using LD flap was done. Case2: A 51-year-old woman with left breast cancer visited for breast reconstruction after radical mastectomy. Initially, breast reconstruction with pedicled TRAM was performed. Postoperatively fat necrosis was developed. Secondary breast reconstruction using LD flap was done. Results: Secondary breast reconstruction using LD flap survived completely and produce successful reconstruction. There was no significant complication in both patients. Conclusion: LD flap provides sufficient, vascularized skin and soft tissue. The flap can be molded easily to replace deficient tissue in all areas of the breast. These attributes make it an ideal candidate for salvage of the partially failed TRAM flap breast reconstruction.

초급성 허혈성 뇌졸중 환자에서 유로키나제를 이용한 국소적 동맥내 혈전용해술의 임상결과에 영향을 미치는 요인

송재민,윤웅,김재규,서정진,허숙희,박진균,정용연,강형근 대한영상의학회 2002 대한영상의학회지 Vol.47 No.4

Purpose: To evaluate the clinical outcome and other relevant factors in cases where local intra-aterial thrombolysis (LIT) is used for the threatment of hyperacute ischemic stroke. Materials and Methods: Forty-eight hyperacute ischemic stroke patients were treated by LIT, using urokinase, within six hours of ictus, and for evaluation of their neurological status, the National Institutes of Health Stroke Scale (NIHSS) score was used. Angiographic recanalization was classified according to Mori recanalization grades. Three months after LIT, the outcome was assessed by clinical examination using the modified Rankin scale (good outcome: RS=0-3; poor outcome: RS=4-6). In all patients, the findings of pre- and post-LIT CT, and angiography, as well as neurological status and hemorrhagic complications, were also analysed. Results: Thirty-three patients had occlusions of the middle cerebral artery (MCA), and 15, of the internal carotid artery (ICA). The NIHSS score averaged 16.9 at the onset of therapy and 13.5 at 24 hours later. Successful recanalization (Mori grade 3,4) was achieved in 28 (58.3%) of 48 patients, but in 20 (41.7%) the attempt failed. Twenty-two (45.8%) of the 48 patients had a good outcome, but in (54.2%) the outcome was poor. Thirteen (40.6%) of 32 patients with MCA occlusions and 13 (81.2%) of 16 with ICA occlusions had a poor outcome. Eight patients (16.7%) died. Overall, hemorrhages occured in 20 (41.7%) of 48 patients, with symptomatic hemorrhage in ten. Five (50%) of these ten died. Conclusion: LIT using urokinase for hyperacute ischemic stroke is feasible; patients with MCA occlusions had better outcomes than those with ICA occlusions. Hemorrhagic complications of LIT were frequent, and in cases of symptomatic hemorrhage a fatal outcome may be expected. 목적: 초급성 허혈성 뇌졸중 환자에서 국소적 동맥내 혈전용해술시 결과와 예후에 영향을 미치는 요인을 알아보고자 하였다. 대상과 방법: 뇌경색 증상 발현 6시간 이내에 유로키나제를 사용하여 국소적 동맥내 혈전용해술을 시행했던 초급성 허혈성 뇌졸중 환자 48명을 대상으로 하였다. 시술 전 환자의 신경학적 상태는 National Institutes of Health Stroke Scale(NIHSS) score를 측정하여 평가하였다. 시술 후 혈관조영상 폐색혈관의 재개통은 Mori 등급을 이용하여 분류하였고, 임상결과 판정은 혈전용해술 시행 3개월 후에 Modified Rankin scale(MRS)을 이용하여 0-3등급인 경우 만족, 4-6등급인 경우 불만족으로 분류하였다. 또한 모든 환자에서 혈전용해술 시행 전후의 전산화단층촬영과 혈관조영소견, 신경학적 상태 그리고 뇌출혈유무에 대해 분석하였다. 결과: 시술전 혈관조영상 중대뇌동맥의 폐색이 32명, 내경동맥의 폐색이 16명이었다. 시술전 평균 NIHSS score는 16.9였으며, 시술 24시간 후에 13.5였다. 성공적인 뇌혈관 재개통은 48명중 28명(58.3%)이었으며, 부분적인 재개통이나 재개통이 되지 않았던 경우는 20명(41.7%)이었다. 시술 후 임상결과는 48명중 22명(45.8%)에서 만족스런 결과를, 26명(54.2%)에서 불만족스런 결과를 보였다. 이중 중대뇌동맥 폐색이 있었던 32명중 13명(40.6%)과 내경동맥 폐색이 있었던 16명중 13명(81.2%)에서 불만족스런 결과를 보였다. 시술 후 3개월이내에 8명(16.7%)이 사망하였다. 48명중 20명(41.7%)에서 뇌출혈이 발생했고, 이중 10명은 증상을 동반하였으며, 증상이 있는 뇌출혈이 있었던 10명중 5명(50%)이 사망하였다. 결론: 초급성 허혈성 뇌졸중 환자에서 유로키나제를 이용한 국소적 동맥내 혈전용해술을 시행한 결과 중대뇌동맥의 폐색 환자가 내경동맥 폐색 환자에 비해 임상 결과가 좋았으며, 시술후 증상이 있는 뇌출혈의 합병증이 있었던 환자에서 치명적인 결과를 예측할 수 있었다.

Parenteral, non-live rotavirus vaccine: recent history and future perspective

송재민 대한백신학회 2021 Clinical and Experimental Vaccine Research Vol.10 No.3

Since the widespread introduction of oral and live attenuated rotavirus vaccines around the world in 2009, the impacts of disease burden and the effects of disease reduction in developing countries have been proven. However, in low and middle-income countries, the vaccine efficacy is somewhat lower than in developed countries due to differences in nutritional conditions, microbial environments of individuals, and other factors. In addition, as oral, live vaccines have been found to be associated with rare but serious side effects, the development of a next-generation vaccine with safety, improved effectiveness, and ease of storage is currently underway. New vaccine strain developed by the Centers for Disease Control and Prevention in the United States are undergoing preclinical testing of efficacy, antigen dose, and administration route in the form of a heat-treated inactive vaccine, and a recombinant protein-based trivalent subunit vaccine developed by the Program for Appropriate Technology in Health is undergoing clinical trial in phase III. Several research groups are also developing non-replicating protein-based rotavirus vaccines using virus-like particles and nanoparticles. This review provides a brief overview of the development status and technology of parenteral, non-live rotavirus vaccines worldwide.

교통사고 예방을 위한 교통사고 원인 데이터 활용방안

송재민,김명수,최진,임효진 대한교통학회 2020 대한교통학회 학술대회지 Vol.83 No.-