Organic Solar Cells: Solution‐Processable Reduced Graphene Oxide as a Novel Alternative to PEDOT:PSS Hole Transport Layers for Highly Efficient and Stable Polymer Solar Cells (Adv. Mater. 42/2011)

Yun, Jin‐,Mun,Yeo, Jun‐,Seok,Kim, Juhwan,Jeong, Hyung‐,Gu,Kim, Dong‐,Yu,Noh, Yong‐,Jin,Kim, Seok‐,Soon,Ku, Bon‐,Cheol,Na, Seok‐,In WILEY‐VCH Verlag 2011 Advanced Materials Vol.23 No.42

<P>Solution‐processable reduced graphene oxide as a hole‐transporting layer for highly efficient and stable organic solar cells is reported on page 4923 by Dong‐Yu Kim, Seok‐In Na, and co‐workers. Introduction of a newly reduced graphene oxide by simple solution processing into solar cells dramatically raises the cell efficiency and cell life‐time. The results will allow full use of chemically reduced graphene and will advance the realization of carbon‐based printable optoelectronic devices. </P>

Estimation of the Extreme Value Index Ⅱ : Efficiency Optimal Estimators 효율 및 최적 추정량

Yun, Seok Hoon 수원대학교 기초과학연구소 1997 基礎科學論文集 Vol.6 No.-

극단값 지수의 추정량으로서 Falk(1994)가 제시한 추정량과 Yun(1997)이 제시한 추정량은 모두 Pickands 추정량의 저효율을 개선시키는 효과가 있다. 본 논문에서는 Falk의 추정량과 Yun이 제시한 추정량이 각기 최적의 방법으로 선택되었을 경우 점근적으로 동일한 효율을 가짐을 보인다. 또한, 유한표본의 경우 시뮬레이션을 통하여 Yun의 추정량이 Falk의 추정량보다 우수함을 보인다.

A Study on the Miniaturization of a Protective Device for the Micro Smart Grid Simulator

Yun‑Seok Ko,Kyung Ryu,Min‑Soo Oh,Hyuk‑Sik Yoon 대한전기학회 2020 Journal of Electrical Engineering & Technology Vol.15 No.1

In this paper, a miniaturization methodology of protective devices (PDs) was proposed which plays a key role in evaluating the efectiveness of the developed protection and control algorithms in the micro smart grid simulator. The micro PD was designed to have the rated voltage of 19 V and the breaking current of 20 A, and was designed in a multi-layered hardware structure to satisfy the size of 13×13 cm2 . Also, the micro PD was designed in a multifunctional structure to allow one micro PD to perform all the functions of the circuit breaker, recloser and switches on the micro smart grid simulator to enhance the efciency of development. Finally, it was verifed that the developed micro PD can be applied as protective devices of the micro smart grid simulator by showing that it operates correctly according to the predetermined operation sequence for the test scenarios on the built test system.

Gilbert 증후군에서 열량 제한 시험과 Phenobarbital 자극 시험의 의의(14예)

이헌영,채경훈,정재훈,강윤세,김연수,문희석,박기오,이엄석,김선문,김석현,성재규,이병석,이강욱 충남대학교 의학연구소 2003 충남의대잡지 Vol.30 No.2

Gilbert 증후군은 인구의 7%에서까지 나타날 수 있는 매우 흔한 증후군으로서 비진행성인 양성의 만성적 경과를 치하며, 간질환의 증상과 징후가 없는 경한 비포합형 고빌리루빈혈증이 특징인 일종의 체질적인 증상으로서 혈장 빌리루빈 농도에 대한 사춘기의 영향 때문에 10대와 20대에 자주 진단이 된다. 따라서 임상적인 중요성은 미약하지만 높은 빈도가 예상되는 점에 그 중요성이 부여되어야 할 것이다. 따라서 적정한 임상적 진단법으로 기왕에 소개된 열량제한 시험과 phenobarbital 유도 시험을 시행하고 이들의 진단적 가치를 알아보기 위하여 본 연구를 시행하였다. 1990년 7월부터 1999년 4월까지 충남대학교병원에 내원하여 HBsAg, IgG anti-HBc 및 anti-HCV가 음성이고, 간 초음파 스캔에서 이상이 없으며, 혈청 AST, ALT 및 AP가 정상인 비음주자에서 경한 비포합형 고빌리루빈혈증이 있는 14예의 환자들을 대상으로 ^(99m)Tc-DISID 스캔을 시행하였으며, 기저 치 총빌리루빈 및 포합형 빌리루빈 치를 측정한 다음에 하루에 400Kcal로 48시간동안 제한한 열량 제한 시험을 시행하였고, phenobarbital을 하루 60mg씩 5일간 투여한 후에도 각각 총빌리루빈과 포합형 빌리루빈 치를 검사하여 비포합형을 구하였다. 대상 환자들은 모두 14예로서 남자가 11예(78.6%)였고 여자가 3예(21.4%)여서 3.7:1로 남자에서 많았으며, 20대가 6예(42.9%), 30대가 역시 6예(42.9%) 및 40대가 2예(14.2%)로서 2,30대가 대부분(85.8%)이었다. 열량 제한 시험 후의 총빌리루빈 치, 비포합형 및 포합형 빌리루빈 치들은 평균 각각 5.5±2.7, 4.2±2.3 및 1.3±10mg/dL 로서, 시험 전 치들인 3.0±0.8, 2.2±0.8 및 0.7±0.4mg/dL 보다 유의하게(p=0.001, p=0.001, p=0.023) 상승하였다. 포합형 빌리루빈 치도 유의하게 상승하였으나 비포합형의 상승보다는 훨씬 낮아서 주로 비포합형이 증가하였다. phenobarbital 투여 중 설사가 발생하여 중단한 1예를 제외한 13예에서 열량 제한 시험 후에 상승하였던 총, 비포합형 및 포합형 빌리루빈 치가 phenobarbital 유도 시험후에는 2.0±1.1, 1.5±0.8 및 0.5±0.4mg/dL로서 열량 제한 시험 결과보다 유의하게 낮아졌고(p=0.00, p=0.000, p=0.001), 열량 제한 시험 전의 기초치들인 3.0±0.8, 2.2±0.8 및 0.7±0.4mg.dL 보다도 더욱 낮아졌으며 유의한 차이(p=0.001, p=0.02, p=0.005)를 나타내었다. 14예에서 시행한 ^(99m)-Tc DISIDA 스캔에서 9예(64.3%)가 정상이었고, 5예(35.7%)에서는 심장 및 신장으로의 간외 섭취가 3예였고, 60분까지 소장 배출이 없는 배설 지연 예와 담낭 수축 불량 예가 각각 1예 씩 발견되었다. Phenobarbital 투여시험에서 민감도가 열량제한시험에 비해 더 높았다(92.3%와 50.0%). Gilbert 증후군에서 1일 400 Kcal로 48시간의 열량제한 시험과 1일 60mg의 phenobarbital을 5일간 투여하는 유도 시험은 편리하고 유용한 임상적인 진단법으로 이용할 수 있다고 생각된다. 그러나 열량 제한 시험에서는 증가 기준의 통일이 필요하다고 유추되며 phenobarbital 유도 시험이 민감도가 더 높은 것으로 생각된다. Gilbert's syndrome is very frequent and benign chronic process characterized by mild, intermittent, unconjugated hyperbilirubinemia without any symptom and sign of liver disease. Previously intoduced caloric restriction test and phenobarbital stimulation test as two appropriate clinical tests had been examined and their diagnostic values were reevaluated. Fourteen patients with mild, persistent, unconjugated hyperbilirubinemia were included. Subsequently caloric restriction has been applicated by 400 Kcal/day for 48 hours and phenobarbital has been prescribed by 60 mg/day for 5 days. Therafter serum levels of total and direct bilirubin were measured. Most of the patients were third and fourth decade(85.8%) and male predominant. Each basal serum levels of total, indirect and direct bilirubin were 3.0±0.8, 2.2±0.8 and 0.7±0.4 mg/dL. After caloric restriction test, each levels were increased significantly to 5.5±2.7, 4.2±2.3 and 1.3±1.0 mg/dL(p=0.001, p=0.001, p=0.023). After phenobarbital stimulation test for 13 patients had been practiced, increased levels of each bilirubin after caloric restriction test were decreased significantly to 2.0±1.0, 1.5±0.8 and 0.5±0.4 mg/dL(p=0.000, p=0.000, p=0.001) and these levels were significantly lower than basal levels(p=0.001, p=0.02, p=0.005). The sensitivities of caloric restriction test were 85.7%, 50.0%, and 71.4%, 35.7%(1.0, 1.5 mg increase of total bilirubin and 1.0, 1.5 mg/dL increase of indirect bilirubin). The sensitivities of phenobarbital stimulation test were 93.2% and 92.3% at criteria of 1.5 mg/dL increase of total bilirubin and indirect bilirubin. On the diagnosis of Gilbert syndrome, caloric restriction test and phenobarbital stimulation test are convenient and useful diagnostic tools in clinical face. And also phenobarbital stimulation test has higher sensitivity than caloric restriction test. Furthermore, standardization of bilirubin increment would be necessary in caloric restriction test.

휴대폰용 FBAR Duplexer에 내장되는 위상천이기에 관한 연구

윤석출,송인상,이연승,김학선 한밭대학교 정보통신전문대학원 2004 정보통신전문대학원 논문집 Vol.2 No.1

본 논문은 WCDM용 Duplexer의 소형화를 위한 집적화된 1×lmm^(2)이하 크기의 RF Phase Shifter를 설계 하고 제작 평가하였다. 제안된 Phase Shifter는 PCB상에서 긴 마이크로스트립 라인 대신에 실리콘 기판 상에 집중 수동 소자인 high-Q 인덕터와 MIM 커패시터로 구현되었다. 제작된 Phase Shifter를 측정한 결과 삽입손실은 0.37 dB를 얻었고, 입력 VSWR은 15.69 dB를 얻었으며, 위상은 81˚를 얻었다. 크기도 0.8×O.9㎟ 로 제작되어 Phase Shifter의 소형화의 가능성을 보였다. In this paper, we have designed, and evaluated the integrated RF phase shifter to reduce the chip size below 1×1mm^(2) for WCDMA duplexer application. Instead of the large transmission lines on the PCB, the proposed phase shifter was used small-sized lumped elements, such as integrated high-Q inductor and MIM capacitors on silicon substrates. In the measurement results of the fabricated phase shifters, the insertion loss was 0.37dB and input VSWR was 15.68dB, the phase was 81˚. Also, the final chip size was 0.8×0.9㎟, which clearly showed the feasibility of the miniaturized RF LC phase shifter.

고혈압 환자들의 건강행태

김석범,강복수,윤성호,황정희,이경수 韓國保健敎育.健康增進學會 2000 보건교육건강증진학회지 Vol.17 No.1

This study was conducted to examine health behaviors in hypertensive patients and the factors that would affect these healthy life-styles, and to provide basic data for effective and continuous hypertension control in private medical facilities. Among those patients diagnosed as hypertension who had visited the Department of Internal Medicine of Yeungnam University Hospital during the two month period from August 2 to September 30, 1999, the present study included 222 patients who were in more than one month after the initial diagnosis of hypertension and those who had hypertension for less than 10 years. Using a structured questionnaire, the present study was conducted by a self-administered survey method, and the obtained data were analyzed with t-test, χ2-test and one-way analysis of variance using the SPSS statistical program. The scores on knowledge related to hypertension were higher as the education level of a patient was higher(p〈0.05). As for occupation, those who performed office or management jobs showed higher scores than those who were into manufacturing jobs, and as for economic status, although those patients who were in middle class showed highest scores, however, no statistical significance was observed. The scores of knowledge on hypertension was higher when the family history hypertension was present(p〈0.05). The scores of health-related behaviors were higher with higher education level and higher economic status, higher in those with family history of hypertension, and higher in those with office or management jobs than those who had manufacturing jobs(p〈0.05). Blood pressure measurement on regular basis was performed most frequently in those who were between 50∼59 years old with 83.3% and was least frequent in those who were older than 70 years old with 50%(p〈0.05). The frequency of regular blood pressure measurement was higher with higher education level, higher economic status, higher in those with family history of hypertension, and the highest in those with management position with 93.5%, however, on statistical significance was observed. Changes in health-relaxed behaviors after hypertension diagnosis were higher with higher education level, higher economic status, and in those patients performed office or management work. In particular, diet change was observed in female and higher economic status and smoking cessation was observed in 60∼69 years old. Housewives and office workers or managers have taken exercise more regularly and those who had management jobs and had high scores on knowledge related to hypertension would participate health education program more actively. Thus, for improving health-related behaviors for continuous management of hypertension, changes in health-related behaviors can be followed through conduction health education to improve understanding of knowledge related to hypertension as the method of helping to improve changes in health life-styles in those with little education and those in low economic status.

인터넷 취업알선의 형성배경과 개선방향

윤석천,어수봉,김주일,이재엽 한국항공대학교 경영연구소 2000 경영연구 Vol.7 No.2

인터넷 취업알선은 디지털시대로의 변화에 따라 취업의 새로운 패러다임으로 대두되고 있다. 인터넷 취업알선의 대두를 거래비용이론의 접근에 따르면 탐색비용을 비롯한 거래비용은 줄어드는 대산 도덕적 해이와 역선택 비용은 증가하는 것으로 분석된다. 따라서 인터넷 취업알선이 확산되기 위해서는 두가지 방안이 제시될 수 있다. 단기적으로는 도덕적 해이와 역선택을 축소하기 위하여 개인정보 보호 및 보안 등을 비롯한 시장질서를 정립하는 것이며, 장기적으로는 새로운 비용의 증가분을 담보하는 신뢰의 구축을 위하여 채용부터 인사노무관리 및 해고에 이르기까지 전과정을 수행할 수 있는 인적자원 종합 기업을 육성하고 양성하는 것이다. The internet employment service becomes new paradigm of recruiting in the digital ages. Transaction cost approach explains that emergence of internet employment service results from the reduction of selection and recruiting cost. Because transaction cost is reduced utilizing internet tool, internet employment service becomes very popular. But that service increase the cost of moral hazard and adverse selection. The effective strategy of internet employment service enlargement make, shortly, a rule of internet employment market including solving the security and safety problems. The long term strategy i s developing the human resource firms with the integrated HRM functions in order to basically solve the moral hazard and adverse selection problem by the formation of trust.

순천향대학교 천안병원에 입원한 로타바이러스 감염 위장관염 환자의 임상양상

최석주,전세윤,김승수,박경배,김용배,박준수 순천향의학연구소 2006 Journal of Soonchunhyang Medical Science Vol.12 No.1

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수냉쿨러의 냉각 효율 향상을 위한 플레이트 부품의 형상에 관한 연구

성윤호,김형찬,김선민,윤석영,이영웅,이상욱 순천향대학교 부설 산업기술연구소 2021 순천향 산업기술연구소논문집 Vol.27 No.2

This study investigates changes in cooling efficiency for heat sink plate width, perforated width, and chamfer angle as part of a parameter study to maximize cooling efficiency of heat sink by setting various variables on plates. The width of the plate is set to 16, 20, 24, 28 mm, perforated width 1.5, 2.0, 2.5 mm, chamfer angles 5, 10, 15 and 20°. By conducting a computational study with Ansys Fluent, the sink plate with plate width of 16mm, perforated width of 3mm and chamfer angle of 10° is shown to be the best cooling efficiency.

저압 아크 고장 차단 기술에 대한 기초 조사 연구

고윤석 남서울대학교 2008 남서울대학교 논문집 Vol.14 No.-

The ELCB(Earth Leakage Circuit Breaker) determines whether the earth leakage is or not by comparing the sensitive current furnished from ZCT(Zero Current Transformer) with the predefined threshold value. However, it can not recognize the arc fault in which the magnitude of fault current is very small and so, the arc fault is expanded into very severe electrical fire. The America has propelled making the laws for the arc fault protection from 1999, and NEC(National Electrical Code) defines and mandates the installation of the AFCI(Arc Fault Current Interrupter)s in diverse places such as bedroom, living room, dinner room, sunroom and closets in 2008. GE and Siemens developed the determination technology of arc fault by making R&D effort for AFCI practicalization, and to mitigate the electrical fire, the developed AFCIs are applied widely to home. However, the effort of us about this field is insufficient, and the level also is very low. Accordingly, this paper surveys and analyzes systematically the basic technology needed in developing the arc fault determination technology. Key Words : AFCI, Electrical Panel, ELCB, ZCT, NEC