Coupled Inductor-Based Parallel Operation of a qZ-Source Full-Bridge DC-DC Converter

이형민,김흥근,차헌녕,전태원,노의철 전력전자학회 2015 JOURNAL OF POWER ELECTRONICS Vol.15 No.1

This study presents a novel transformer isolated parallel connected quasi Z-source (qZ-source) full-bridge DC-DC converter that uses a coupled inductor in both the qZ-source network and output filter inductor. Unlike traditional voltage-fed or current-fed converters, the proposed converter can be open- and short-circuited without damaging switching devices. Therefore, the desired buck and boost functions can be achieved and converter reliability can be significantly improved. All the bulky inductors in the qZ-source network and output filter can also be minimized with the proposed inductor structures. A 4 kW prototype DC-DC converter is built and tested to verify the performance of the proposed converter.

외상성 횡격막 손상

이형민 대한흉부심장혈관외과학회 1994 Journal of Chest Surgery (J Chest Surg) Vol.27 No.8

We evaluated sixteen patients of traumatic diaphragmatic injuries that we have experienced from Jan. 1987 to Aug 1993. Age was ranged from 6 to 71 years, predominantly in the fourth and fifth decades. 13 were male and 3 were female, a ratio of 4.3: 1. Blunt trauma was develped in 11 [Lt 7, Rt 4], penetrating trauma in 5 [Lt 2, Rt 3]. Preoperative diagnosis of diaphragmatic injury was possible in 8 patients [72.2 %] in blunt trauma, and 1 patient [20 %] in penetrating trauma. 8 cases[54.5%] in blunt trauma, and 4 cases in penetrating trauma were treated within 24 hours,meanwhile, patients treated after 10 days were 3, all by blunt trauma.The repair of 16 cases were performed with thoracic approach in 4 cases, thoracoabdominal approach in 3 cases, and abdominal approach in 9 cases. The herniated organs in thorax were stomach [5], colon [3], liver [2], and pancreas [1]. Postoperative complication were developed in 9cases[56.3%] significantly related with delayed operation time [p < 0.01 ]. Hospital mortality was 12.5 % [2/16], and the causes of death were hypovolemic shock in one and hepatic failure due to portal vein rupture in another.

선천성 기관 협착환자에서 늑연골 절편을 이용한 기관성형술 1례

이형민 대한흉부심장혈관외과학회 1994 Journal of Chest Surgery (J Chest Surg) Vol.27 No.5

Congenital long-segment tracheal stenosis which involves nearly entire trachea and carina is very rare disease, but leads to life threatening obstruction in infancy and childhood. Symptoms are ranged from stridor and wheezing to severe cyanosis and respiratory failure. Routine chest X-ray is somewhat helpful to diagnose it, but definitive diagnosis can be made by bronchoscopy or tracheogram for severely narrowed tracheal lumen.Recently, we experienced a case of congenital tracheal stenois, type 1 by Cantrell classification with carinal involvement. After costal cartilage was designed as oval shaped flap and covered with pericardium, anterior and posterior augmentation was done with prepared costal cartilage.This patient died of respiratory failure at 13 days postoperatively, probably due to sustaining obstruction in association in with failure to make a sufficient widening at carinal level.Important issues in the management of congenital tracheal stenosis are rapid diagnosis, selection of appropriate surgical procedure, and detailed anesthetic schedule.In the future, more biocompatible material and more effective surgical procedures should be studied to reduce the surgical mortality and morbidity of the complicated tracheal stenosis.

원자력 발전소 관련 미디어 노출이 원자력 관련 태도와 행동의도에 미치는 영향

이형민 한국광고PR실학회 2018 한국광고PR실학회 학술대회 Vol.2018 No.06

OOH(Out-of-Home) 광고 매체 유효접촉인구의 과학적 측정 : WiFi 감지 기술과 수용자 시선 행태 측정(Eye-tracking) 기술의 복합 적용 사례 연구

이형민,김신엽,천용석 한국지역언론학회 2019 언론과학연구 Vol.19 No.2

This study was designed to measure the audience exposure to OOH(Out-of-Home) advertising in a more scienctific and sophisticated way. With a couple of newly emerging technologies, WiFi sensing detector and eye-tracking device, we attempted to empirically measure the effects of OOH advertising. WiFi sensing technology was used to identify the number of people who were potentially exposed to the OOH advertising. In addition, we used wireless mobile communication subscriber information to identify the demographic characteristics of such people. We also attempted to analyze physiological responses to the OOH advertising with eye-tracking devices, and further, to calculate the cost effectiveness (CPM) of OOH advertising. This study aimed to empirically validate and discuss the advantages and limitations of such technologies in measuring OOH advertising effectiveness and efficiency. 본 연구는 최근 새롭게 등장하고 있는 여러 가지 기술들을 활용하여 보다 과학적 이고 정교한 방법으로 OOH(Out-of-Home) 광고 매체에 대한 유효접촉인구를 측 정해 보고, 주목 효과와 효율성을 산출하기 위해 설계되었다. 보다 구체적으로 WiFi 감지 기술과 무선이동통신 가입자 정보를 활용하여 OOH 광고 게첨 지역을 통행하 는 유동인구의 수를 파악하고, 이러한 사람들의 인구사회학적 특성을 추론해 보았 다. 또한 수용자 시선 행태 측정(Eye-tracking) 기술을 이용하여 실제 OOH 광고 게첨 지역을 통행하는 보행자들의 생리적 반응과 광고 주목 효과 측정을 병행함으로 써 OOH 광고의 비용 효율성(CPM: Cost Per Millenium) 산출을 시도하였다. 연 구 결과, WiFi 감지 기술을 활용하여 OOH 광고 게첨 지역의 유동인구를 계측할 경우 여러 가지 차별적인 방법론상의 장점들이 있었다. 또한 무선이동통신 가입자 정 보를 더해 OOH 광고 게첨 지역의 유동인구를 분석할 경우 과거에는 입수가 거의 불 가능했던 정보(연령대별, 거주지별 등)를 추출할 수 있었으며, 이를 전략적인 OOH 광고 기획 및 집행에 활용할 수 있다는 사실을 확인할 수 있었다. 뿐만 아니라 수용 자 시선 행태 측정 연구 결과를 통해 OOH 광고 메시지 주목률을 산정함으로써 이전 까지 불가능하다고 여겨졌던 OOH 광고 효율성 측정을 시도하였다. 본 연구는 이러 한 OOH 광고 유효접촉인구 계측 방법에 대한 장점과 한계를 실증적으로 검증하고 논의해 보고자 한다.

소아 어지럼의 원인과 임상 양상

이형민,박지훈,이범상,이건희,박수경,장지원 대한이비인후과학회 2018 대한이비인후과학회지 두경부외과학 Vol.61 No.9

Background and Objectives Dizziness is not uncommon in children. The etiology of dizzinessvaries according to different studies due to different methods of examination or characteristicsof the dizziness center. To assess meaningful causes of dizziness in children, a multidisciplinaryapproach would be needed. The purpose of this study was to analyze the mainpathologies associated with vertigo and dizziness in children, paying particular attention torecent diagnostic advances with a multidisciplinary approach. Subjects and Method A total of 73 children, aged between 4-18 years, who visited thePediatric Dizziness Clinic of the University Hospital from January 2016 to June 2016 were includedin this study. Medical records were reviewed retrospectively. All of the subjects wereexamined by history, questionnaires, physical examinations, electrocardiogram, hematologictests, brain MRI scan, audiogram and vestibular function tests. Patients who had orthostaticsymptoms additionally underwent a tilt table test, and in selective cases, a caloric and vestibularevoked myogenic potential tests as well. Results Vestibular migraine (VM) and benign paroxysmal vertigo of childhood (BPVC)were found in 35.6% and 27.4% of the children with dizziness, respectively. The incidence oforthostatic hypotension and postural orthostatic tachycardia syndrome were 12.3% each, bothof which are higher than other previous reports. Other causes were Meniere’s disease, benignparoxysmal positional vertigo, vestibular neuritis and so on. Conclusion VM and BPVC were the most common causes of pediatric dizziness. Also, theincidence of orthostatic dizziness was rather high in pediatric population. The evaluation of dizzinessin children should include a thorough check of history (questionnaire), neurotologicalexamination, vestibular function tests and a tilt table test.

독사 교상 후에 생긴 뇌경색 1례

이형민,홍훈표,김동필,김명천,고영관 대한응급의학회 2004 大韓應急醫學會誌 Vol.15 No.5

There are only three species of poisonous snakes in Korea. Deaths from poisonous snakebites are rare in Korea, but the World Health Organization estimates that as many as 30,000 to 40,000 death occur following venomous snakebites. The most important factor for determining a prognosis for a victim of a venomous snakebite is the grade of envenomation, because the grade of envenomation is highly correlated with severe complications such as disseminated intravascular coagulopathy, a bleeding tendency, acute renal failure, pulmonary edema, and sepsis. Also, bleeding complications with the central nervous system are well known to occur following a snakebite. However, non hemorrhagic manifestations, such as ischemic stroke, are extremely rare. We report the case of 72-year-old male who suffered a cerebral infarction following a snakebite. We also present a review of the literature of possible mechanisms for the cerebral infarction.

대상적 Reality의 표현

이형민 중앙대학교 예술대학 회화학과 1979 卒業作品硏究報告書集 - 中央大學校 藝術大學 繪畵學科 Vol.1979 No.-

지방자치단체의 국제교류

이형민 경북대학교 지방자치연구소 1999 地方自治硏究 Vol.3 No.-

적극적 매개자의 정파적 허위정보(disinformation) 공유와 확산

이형민 한국PR학회 2023 한국PR학회 학술대회 Vol.2023 No.11