흔들림이 있는 영상의 움직임 방향과 정도의 추정

최지웅,강문기,박규태 한국방송공학회 1997 한국방송공학회 학술대회 Vol.1 No.1

Fabrication of affordable pulse duplication system for the in-vitro cardiovascular experiments based on gear pump and orifice flowmeter

최지웅,Jae Hun Choe,정성용,박한욱,하호진 대한기계학회 2019 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.33 No.8

More than 18 millions of people are still suffering from cardiovascular diseases (CVD) globally. Although various hemodynamics features are known to be related to the development of the CVDs, scrutinizing all hemodynamic features in suffering patients is not technically feasible yet. Instead, in-vitro replications of physiological and pathological blood flows have been preferred to investigate the changes in hemodynamics. In this study, we manufactured affordable pulse duplication system for the in-vitro cardiovascular experiments. The instrument consists of gear pump, servo-motor, servo-driver, data acquisition modulus, reservoir and orifice, which costs less than 7000 $. The two pressure sensors are equipped on the orifice to measure the pulsatile flow rate based on the pressure drop. The flow rate is given to feedback system to exactly duplicate the desired flow waveform. The developed system was tested to replicate various aortic blood flow waveforms with 60 to 120 beat per minute, and the results showed that the pulse duplication system replicates the blood flow waveforms with an error of less than 0.4±0.4 L/min. The duplicated waveform was stable and changed less than 5 % after less than 40 feedback iterations.

HAB 조기탐지를 위한 수중음향기법 연구

최지웅,김정훈,윤영글,강돈혁 대한조선학회 2012 대한조선학회 학술대회자료집 Vol.2012 No.5

전자증권법제의 도입 및 향후 법적 정비 과제

최지웅 한국증권법학회 2019 증권법연구 Vol.20 No.3

Information Technology and digitalization have contributed the advent of the Fourth Industrial Revolution and now expand their influence to the financial market. The advanced IT system and networking have made it possible the automation and integration of primary and secondary securities market, which was difficult to realize, and have played a pivotal role in the enactment of 「the Act on the electronic registration of securities and bonds etc.」 and the electronic securities system based on the act which has been enforced this September. Information Technology and digitalization not only has great influence on the efficiency of instruments but also expand it to the essential areas. Thus it has enabled the processing by electronic system in almost whole areas ranging from issuance and circulation of securities to corporate actions related securities entitlements not using physical securities. However, electronic securities system has many attributes which are different from those of existing law theories and systems in that the rights are represented and managed in the form of electronic data not the physical ones though it is the advanced version of the securities deposit system based on the physical securities. Therefore, further detailed study is necessary on what the scope of rights is that can be registered electronically on the electronic ledger and on how the characteristics and scopes of the participants in the electronic securities system can be defined developing the logic at the legislation period. And checks are also necessary on how the legislative structure of the electronic securities system can be harmonized with other existing ones such as Financial Investments Services and Capital Market Act or Commercial Law. For these reasons, 「the Act on the electronic registration of securities and bonds etc.」 enacted in 2016 needs to be checked to find the items which is essential for operating the electronic securities system but has not been reflected, the items to be reflected among the related laws or market changes, and how those are reflected in the respective laws. These efforts can contribute to the completion of advanced electronic law system and the development of capital market. IT기술 및 이로 인한 전자화는 제4차 산업혁명의 출현에 기여하였고 이제는 금융시장에까지 그 영향력을 확대하고 있다. 발달된 IT 시스템과 네트워크에 의하여 기존에는 구현하기 어려웠던 증권의 발행․유통시장의 자동화․통합화가 가능하게 되었고, 올해 9월 시행된 「주식․사채 등의 전자등록에 관한 법률」 및 동법에 근거를 두고 있는 전자증권제도 역시 IT기술과 전자화에 힘입은 바 크다. 이러한 IT기술과 전자화는 단순히 수단을 효율화시키는 데 멈추지 않고 본질적인 영역에까지 범위를 확장하여 발전을 지속하고 있다. 그래서 증권의 발행, 유통 및 권리 행사 등 증권과 관련된 제반 영역에 있어 실물을 사용하지 아니하고 전산 시스템에 의한 처리를 가능하게 한 것이다. 그런데 전자증권제도는 실물 유가증권에 기반한 증권예탁제도를 고도화하여 발전시킨 제도이기는 하나 실물이 아닌 전자적 데이터에 의하여 권리가 표창되고 그 권리가 전자적 방식에 의하여 관리된다는 점에서 기존의 법 이론 및 체계와는 다소 다른 점들이 있다. 그래서 전산적 장부에 전자등록된 형태로 존재할 수 있는 권리의 범위는 무엇이고, 그 권리의 발생․소멸․이전에는 어떠한 법적 효력을 부여할 것이며, 전자증권제도에 참가하는 참가자들의 성격 및 범위는 어떠한지 등에 대해 입법 당시의 판단에서 더 나아가 세부적인 검토가 필요하다. 또한 이러한 전자증권법제는 자본시장법, 상법과 같은 기본 법제와는 어떠한 관계 하에서 조화를 이룰 수 있는 것인지에 대해서도 확인이 필요하다. 이러한 점에서 지난 2016년 제정된 「주식․사채 등의 전자등록에 관한 법률」은 그 제정 시점과 비교하여 보았을 때, 실제 전자증권제도의 운영에 필요하나 미반영되었거나, 관련 법률 또는 시장의 변화 사항 중 반영해야 할 사항에 대한 검토 및 각 법률에의 반영을 위한 정비 사항을 확인할 필요가 있다. 이를 통해 보다 고도화된 전자증권법제의 완성 및 자본시장의 발전에 기여할 수 있다고 생각된다.

콘크리트 포장 양생관리 개선을 위한 계측기반 연구사례 조사

최지웅,손병광,김성민 한국도로학회 2019 한국도로학회 학술대회 발표논문 초록집 Vol.2019 No.09

Impact of Pediatric Alopecia Areata on Quality of Life of Patients and Their Family Members: A Nationwide Multicenter Questionnaire Study

최지웅,김율희,곽현빈,박진,이원수,강훈,김정은,윤태영,김기호,장용현,김도원,김문범,유박린,심우영,전지현,서수홍,권오상,허창훈,이동윤,이양원,박병철,원종현,김도영,김효진,김범준,이영,김상석,최광성 대한피부과학회 2022 Annals of Dermatology Vol.34 No.4

Background: Pediatric alopecia areata (AA) can affect the quality of life (QoL) of patients and their family members. Research on the QoL and burden on family members in pediat- ric AA is limited. Objective: This nationwide multicenter questionnaire study described the QoL and burden of the family members of patients with pediatric AA. Methods: This nationwide multicenter questionnaire study enrolled AA patients between the ages of 5 and 18 years from March 1, 2017 to February 28, 2018. Enrolled patients and their parents completed the modified Children’s Dermatology Life Quality Index (CDLQI) and the modified Dermatitis Family Impact (mDFI). The disease severity was measured using the Severity of Alopecia Tool (SALT) survey scores. Results: A total of 268 patients with AA from 22 hospitals participated in this study. Our study found that the efficacy and satisfaction of previous treatments of AA decreased as the severity of the disease increased. The use of home-based therapies and traditional medicines increased with the increasing severity of the disease, but the efficacy felt by patients was limited. CDLQI and mDFI scores were higher in patients with extensive AA than those with mild to moderate AA. The economic and time burden of the family mem- bers also increased as the severity of the disease increased. Conclusion: The severity of the AA is indirectly proportional to the QoL of patients and their family members and directly proportional to the burden. Physicians need to under- stand these characteristics of pediatric AA and provide appropriate intervention to pa- tients and their family members.

Fish Composition and Trophic Guild Analysis as a Collection of Basic Data for Ecosystem Health Assessments in Yeongsan Lake

최지웅,An Kwang-Guk 한국하천호수학회 2007 생태와 환경 Vol.40 No.4

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Predictive Factors of the Outcome of Extracorporeal Shockwave Lithotripsy for Ureteral Stones

최지웅,송필현,김현태 대한비뇨의학회 2012 Investigative and Clinical Urology Vol.53 No.6

Purpose: Extracorporeal Shock Wave Lithotripsy (ESWL) has shown successful outcomes for ureteral stones. We investigated predictive factors for failure of ESWL for treating ureteral stones. Materials and Methods: A total of 153 patients who underwent ESWL between July 2006 and July 2009 for ureteral stones diagnosed by non-enhanced spiral computed tomography were divided into two groups: (group A, stone size ≤10 mm; and group B, stone size >10 mm). The failure was defined as remnant stones >4 mm. We assessed age, sex, body mass index, stone size, laterality, location, skin-to-stone distance (SSD), Hounsfield unit, and the presence of secondary signs (hydronephrosis, renal enlargement, perinephric fat stranding, and tissue rim sign). We analyzed predictive factors by using logistic regression in each group. Results: The success rates were 90.2% and 68.6% in group A and B, respectively. In the univariate analysis of each group, stone size, SSD, and all secondary signs showed statistically significant differences in terms of the outcome of ESWL (p<0.05). In the multivariate logistic regression, stone size (odds ratio [OR], 50.005; 95% confidence interval [CI], 6.207 to 402.852) was an independent predictive factor in group A. The presence of perinephric fat standing (OR, 77.634; 95% CI, 1.349 to 446.558) and stone size (OR, 19.718; 95% CI, 1.600 to 243.005) were independent predictive factors in group B. Conclusions: Stone size is an independent predictive factor influencing failure of ESWL for treating ureteral stones. In larger ureteral stones (>10 mm), the presence of perinephric fat stranding is also an independent predictive factor. Purpose: Extracorporeal Shock Wave Lithotripsy (ESWL) has shown successful outcomes for ureteral stones. We investigated predictive factors for failure of ESWL for treating ureteral stones. Materials and Methods: A total of 153 patients who underwent ESWL between July 2006 and July 2009 for ureteral stones diagnosed by non-enhanced spiral computed tomography were divided into two groups: (group A, stone size ≤10 mm; and group B, stone size >10 mm). The failure was defined as remnant stones >4 mm. We assessed age, sex, body mass index, stone size, laterality, location, skin-to-stone distance (SSD), Hounsfield unit, and the presence of secondary signs (hydronephrosis, renal enlargement, perinephric fat stranding, and tissue rim sign). We analyzed predictive factors by using logistic regression in each group. Results: The success rates were 90.2% and 68.6% in group A and B, respectively. In the univariate analysis of each group, stone size, SSD, and all secondary signs showed statistically significant differences in terms of the outcome of ESWL (p<0.05). In the multivariate logistic regression, stone size (odds ratio [OR], 50.005; 95% confidence interval [CI], 6.207 to 402.852) was an independent predictive factor in group A. The presence of perinephric fat standing (OR, 77.634; 95% CI, 1.349 to 446.558) and stone size (OR, 19.718; 95% CI, 1.600 to 243.005) were independent predictive factors in group B. Conclusions: Stone size is an independent predictive factor influencing failure of ESWL for treating ureteral stones. In larger ureteral stones (>10 mm), the presence of perinephric fat stranding is also an independent predictive factor.

부분철근 및 연속철근을 사용한 신개념 철근콘크리트 포장(ARCP) 시험시공

최지웅,손병광,김태형,김성민,이준호 한국도로학회 2020 한국도로학회 학술대회 발표논문 초록집 Vol.2020 No.09

RML 매핑에 기반한 RDF 지식 그래프 구조 검증을 위한 SHACL 스키마의 자동 생성

최지웅 한국컴퓨터정보학회 2022 韓國컴퓨터情報學會論文誌 Vol.27 No.9

In this paper, we propose a system which automatically generates SHACL schemas to describe and validate RDF knowledge graphs constructed by RML mappings. Unlike existing studies, the proposed system generates the schemas based on not only RML mapping rules but also metadata extracted from RML mapping input data in various formats such as CSV, JSON, XML or databases. Therefore, our schemas include the constraints on data type, string length, value range and cardinality, which were not present in the existing schemas. And we solves the problem with "repeated properties" which overlooked in existing studies. Through a conformance test consisting of 297 cases, we show that the proposed system generates correct constraints for the graphs. The proposed system can contribute to automation of the tedious and error-prone existing manual validation processes. 본 논문에서는 RML 매핑 방식으로 구축한 RDF 지식 그래프의 구조를 묘사하고 검증할 용도의SHACL 스키마를 자동으로 생성하는 시스템을 제안한다. 제안하는 시스템은 기존 연구와는 달리RML 매핑 규칙 뿐만 아니라 RML 매핑의 입력인 CSV, JSON, XML, 데이터베이스와 같은 다양한포맷의 데이터에서 추출한 메타데이터도 함께 사용하여 스키마를 생성한다. 따라서 기존 연구 기반의 스키마에서는 부재했던 데이터 타입, 문자열 길이, 값의 범위, 차수 관련 제약 조건이 스키마에 포함된다. 그리고 기존 연구에서 간과한 소위 반복된 속성 문제를 제안하는 시스템은 해결한다. 297개의 케이스로 구성된 적합성 테스트를 통해 제안된 시스템이 그래프에 대한 올바른 제약 조건을 생성함을 보여준다. 제안된 시스템은 오류가 발생하기 쉬운 기존 수동 검증 프로세스를 자동화하는 데 기여할 수 있다.