기획특집 2 - 미래 그린카 시장의 전망과 대응

성낙환,Seong, Nak-Hwan 대한석유협회 2009 석유와 에너지 Vol.273 No.-

전력계통의 실시간 대칭성분 계산을 위한 알고리즘에 관한 연구

신명철,이복구,성낙환 成均館大學校 科學技術硏究所 1987 論文集 Vol.38 No.1

Nowadays as the power systems have been more complicated and have grown to ultra high voltage, it requires an accurate and high speed relaying scheme to improve the reliablity and stability of power systems for a harmonious power supplying. This paper presents a real-time algorithm for calculating symmetrical components from the distorted transient voltage and current signals in a power system. To compute the sequence components and hence to analyze the nature of the disturbance it is necessary to extract the fundamental frequency signals from the noise-ridden transient signals. The fundamental frequency components are filtered out from the transient signals using discrete Fourier technique. The fundamental frequency components of the 3-phase signals are first extracted using an algorithm based on discrete Fourier transformation and then real-time symmetrical components transformation is applied to obtain the sequence components. The algorithm presented is computationally efficient and fast. Experiment results on artificial transmission line demonstrate the validity of the proposed algorithm.

맥반석의 용출시험 및 중금속 흡착특성

김종부,신명국,성낙환,최문정,김경주,이동석 강원대학교 산업기술연구소 2000 産業技術硏究 Vol.20 No.A

This experiment was done to investigate the leaching and adsorption properties of heavy metals on porphyry. The comparison with respect to the leachability of heavy metals from porphyry between the Korea Standard Leaching Test (KSLT) and the Toxicity Characteristic Leaching Procedure (TCLP) was carried out. The fractional composition of leachate and the total concentration of heavy metal of porphyry were studied through Sequential Extraction Procedure (SEP) and EPA Method 3050. Adsorption experiment of porphyry has pointed out that the optimum dosage of porphyry for 50ppm Pb was over 10g/L, the effective particle size for absorption was below 200 mesh and the optimum pH was about 7. From the Freundlich' adsorption equation, l/n was 1.0722, and k was 0.0041. After adsorption, the fractional composition of Pb was changed. The exchangeable, carbonate, reducible fractions were increased, and the organic fraction was not changed, and the residual fraction was decreased.

모야모야병(Moyamoya disease) 환자의 치과치료시 고려사항 : 증례 보고

도레미,유태민,성낙환,송승례,신수일 대한통합치과학회 2019 대한통합치과학회지 Vol.8 No.1

Moyamoya disease is a chronic, progressive cerebrovascular disorder that leads to an abnormal vascular network at the base of a brain due to the stenosis or occlusion of the internal carotid artery. The purpose of this study is to provide a review of dental treatment considerations for Moyamoya disease patients. According to the article review, dental treatment of patients with Moyamoya disease needs the following considerations. Firstly, the treatment should consider stress reduction therapies. Secondly, bleeding tendency of patients should be taken into consideration. Lastly, medication treatment should be considered. As Moyamoya disease can be a progressive systemic vascular disease, if a bleeding operation is required in the dental treatment then medical consultation by a professional should precede the treatment. 모야모야병(Moyamoya disease)은 뇌경동맥의 협착이나 폐쇄에 의해서 뇌기저부에 비정상적 혈관망을 갖는 만성 진행성 뇌혈관 질환이다. 본 연구에서는 모야모야병에 대한 문헌 고찰과 함께 모야모야병 환자의 치과 치료 증례를 보고하면서, 모야모야병 환자에 대한 치과치료시 고려해야 사항에 대해 살펴보고자 한다. 모야모야병 환자의 치과 치료시 고려사항으로는 첫 번째로, 스트레스 감소 요법에 대한 고려가 필요하다. 두 번째로 출혈 경향에 대한 고려가 필요하며, 세 번째로 약물 처방에 대한 고려가 필요하다. 이 질환은 진행형인 전신 혈관 질환으로 고려될 수 있으므로, 치과 진료시 출혈을 일으키는 침습적 치료가 예정되어 있을시 반드시 의과 협진이 선행되어야 한다.

디지탈 계전기법에 의한 전선로 보호의 최적화

신명철,김철환,성낙환 成均館大學校 科學技術硏究所 1990 論文集 Vol.41 No.1

To maintain the high reliability and stability in the large scale electric power system for a stabilized power supplying, it requires an accurate high speed digital distance relaying techniques. For this purpose, when it comes to faults with the power system, the digital distance relaying techniques must be investigated to extract the fundamental frequency component and to predict fault location. In this thesis, it is presented the methodology of DFT(discrete Fourier transform), which accompanied aliasing, picket -fence effect, and leakage in the process of extracting fundamental frequency component and an algorithm of extracting fundamental frequency component, using the Kalman filter theory to improve upon these disadvantages. Also, a two-state and three---state Kalman filter are considered for the symmetrical components estimatin of voltages and currents respectively. It is presented an efficient digital distance relaying techniques for the purpose of extracting fundamental frequency component. Also, to confirm the validity of Kalman filtering techniques, it is shown the experimental results obtained by using the digital simulation of power system. And, it is discussed the extracted results of fundamental frequency components by means of the Fourier transform and Kalman filtering techniques.

상호상관 함수를 이용한 지중선로 고장점 추정

朴星完,林泳範,鄭州桓,成洛煥,金喆煥,申明徹 成均館大學校 科學技術硏究所 1994 論文集 Vol.45 No.2

This paper is intended as an investigation of fault location for underground line. Over the past few decades a considerable number of studies have been made on protection of underground line. However, these approaches require the interruption of electric power supply from source for fault location estimation. Therefore, we proposed fault location algorithm for underground line protection without interruption of electric power supply. Cross correlation function is used in this algorithm. Also, EMTP data is used to demonstrate the capability of the proposed fault location algorithm.

단국대학교 치과대학병원, 장애 환자의 전신마취 하 치과치료 현황

Tae-min You,성낙환,송승례,신수일,도레미 대한통합치과학회 2018 대한통합치과학회지 Vol.7 No.1

The patients with disability might be treated under general anesthesia according to their disability grade. From January 2011 to September 2017, this study examined whether 3,896 patients (2,342 males and 1,554 females) with disability type and grade were treated under dental general anesthesia in Dankook University Dental Hospital. According to the type of disability, 8,459 cases (36%) were physical disability, 5,009 cases(21%) were mental retardation, and 3,384 cases (15%) were brain lesion disorders. General anesthesia rate was the highest with 247 cases among 936 cases of autistic disorder(26.4%), followed by mental retardation(20.9%) and brain lesion disorders(5.7%). Among patients with these disorders (autistic disorder, mental retardation and brain lesion disorder where general anesthesia rate was high), we observed that those with higher degree of disability (i.e., greater the severity of the disorder) were more likely to be treated under general anesthesia. 단국대학교 치과대학병원에서는 장애 등급이 있는 환자들을 전신마취 하에 치과치료를 하기도 하고, 외래에서 술식을 진행하기도 한다. 본 연구에서는 2011년 1월부터 2017년 9월까지, 장애 유형과 등급이 있는 환자 3,896명(남자 2,342명, 여자 1,554명)명을 대상으로 전신마취 하 치료 여부에 대해 조사를 해보았다. 장애 유형별 내원 현황을 보면, 내원 case 기준으로 8,449건(36%)이 지체 장애였고, 5,019건(22%)가 지적 장애, 3,382건(15%)가 뇌병변 장애였다. 장애 유형별 전신마취 비율을 보면, 자폐성 장애일 경우 938건 중 247건(26.3%)로 전신마취 비율이 가장 높았으며, 그 다음이 지적 장애(20.8%), 뇌병변 장애(5.7%) 순이었다. 전신마취 비율이 높은 자폐성 장애, 지적 장애, 뇌병변 장애에서는 장애 등급이 높을수록(장애가 심각할수록) 전신마취 비율이 높은 경향을 보이기도 했다.

지대주 결찰부의 파절 제거 증례 보고

도레미,Tae-min You,신수일,송승례,성낙환 대한통합치과학회 2017 대한통합치과학회지 Vol.6 No.1

Various types of removal kits have been offered by several companies to address implant prosthetic complications, but complications are not easy to resolve. In particular, the fracture of the internal tapered abutment is difficult to remove with conventional tools if the abutment and the seal inside the fixture are rigid. This clinical report reported a case of abutment fracture in internal taper connection type fixture. A 63-year-old male patient presented with a broken implant restoration that was connected into an internal taper type implant. To retrieve the remnant of the broken abutment in the fixture, multiple instruments were applied to break conical seal. The broken abutment was barely removed with rotary diamond instrument, damaging the internal taper connection area of the fixture. Though there was no cold welding was reported, conical tight seal generated by applied preload make difficult to removal abutment without screw.

맥반석의 용출시험 및 중금속 흡착특성

김종부(Kim Jong Boo),신명국(Shen Ming Guo),성낙환(Sung Nak Whan),최문정(Choi Moon Jeong),김경주(Kim Kyung Joo),이동석(Rhee Dong Seok) 강원대학교 산업기술연구소 2000 産業技術硏究 Vol.20 No.1

This experiment was done to investigate the leaching and adsorption properties of heavy metals on porphyry. The comparison with respect to the leachability of heavy metals from porphyry between the Korea Standard Leaching Test (KSLT) and the Toxicity Characteristic Leaching Procedure (TCLP) was carried out. The fractional composition of leachate and the total concentration of heavy metal of porphyry were studied through Sequential Extraction Procedure (SEP) and EPA Method 3050. Adsorption experiment of porphyry has pointed out that the optimum dosage of porphyry for 50ppm Pb was over 10g/L, the effective particle size for absorption was below 200 mesh and the optimum pH was about 7. From the Freundlich’ adsorption equation, l/n was 1.0722, and k was 0.0041. After adsorption, the fractional composition of Pb was changed. The exchangeable, carbonate, reducible fractions were increased, and the organic fraction was not changed, and the residual fraction was decreased.

전력선 통신을 위한 채널 특성 분석

이정훈(J.H. Lee),서종완(J.W. Seo),이종주(J.J. Lee),신명철(M.C. Shin),성낙환(N.H. Sung) 대한전기학회 2000 대한전기학회 학술대회 논문집 Vol.2000 No.7