주택형 태양광발전시설의 전압품질 분석

김세호,김철성 제주대학교 공과대학 첨단기술연구소 2005 尖端技術硏究所論文集 Vol.16 No.2

According to the economy growth and altitude of industrial society life, demands for the electricity enlarge We are faced with serious situation lacking of energy and changes surrounding the earth environment. Related experts commonly have agreed that strong measures must be taken to reserve long-term stability of electricity supply. Meanwhile, solar photovoltatic power generation is drawing most attention from the experts. Because this system uses unlimited and unpolluted solar energy, It doesn't need costs of fuel and doesn't have no air pollution and no waste matter. The paper investigates the influences of Solar photovoltatic power generation system on voltage and harmonics

밀폐에 의한 기계설비 소음의 감쇠 예측

윤세철,오종민 경희대학교 환경연구소 1997 環境硏究 論文集 Vol.7 No.-

The considerations in the noise control by enclosure are the rise of temperature and sound pressure, transmission loss, absorption coefficient of the materials, the structure of the soundproof panels, an opening and coincidence frequency. But it is very difficult that we obtain the accurate data about those in design, so, the noise reduction after enclosing does not correspond. The difference of the noise reduction between the calculation and the measurement was average 4.8dB

시차주사열량분석기를 이용한 치과용 접착시멘트의 경화기전 및 반응열에 관한 연구

김철위,이용근,윤태호,김효종,남세진 大韓齒科器材學會 2000 대한치과재료학회지 Vol.27 No.3

The working time of dental cement has a close relation with the setting time, where the setting reaction can be said as the result of the chemical reaction between cement liquid and powder. The purpose of this experiment was to investigate the setting characteristics and setting rate of dental cements by measuring the exothermic heat(Joule/gram) from the setting reaction at specified times using a differential scanning calorimeter (Differential Scanning Calorimeter, DSC 204, TASC 414/3A Controller, Netzche, Germany). Graphs of time-exothermic heat at 37℃ isothermal condition, showing the setting reaction of dental cements were plotted. Three types of luting cements studied were zinc-phosphate cement (ZPC), polycarboxylate cement (PCC), and glass ionomer cement (GIC). The effects of powder-liquid ratio on the setting characteristics of cements were also included. The amount of heat (calory) released per one gram of cement was calculated at each specified time, and was analyzed. ANOVA and Scheff's multiple comparison test (p=0.05) were used for statistical analysis using SPSS/PC+. The setting rate of cement was not constant during the setting reaction, and different setting characteristics were observed depending on the type of cement and powder/liquid ratio. Generally, 70∼90% of the setting reaction, measured by the exothermic heat release, occurred within 5 minutes after mixing. The exothermic heat released by ZPC was very high immediately after mixing, and the duration of the heat release was prolonged compared with other cements. The exothermic heat release of PCC finished most rapidly. It was generally observed that the amount of heat release (rise in temperature) per one gram of cement was highest for ZPC, followed by GIC, and then PCC. However, heat release during the first 2∼5 minutes after mixing was highest for GIC, followed by ZPC and then PCC. According to the Scheff's multiple comparison test, the duration of the total setting reaction did not show any significant difference among the cements(p>0.05), and also among the different power/liquid ratio groups(p>0.05). It was observed that more heat was released with the lower powder/liquid ratio than the higher powder/liquid ratio.

환경불확실성에 따른 품질경영 활동과 경영성과에 관한 연구

정상철,오세구 충남대학교 경상대학부설 경영경제연구소 1997 경영논집 Vol.13 No.2

본 연구는 품질경영에 대한 이론적 배경을 고찰하고, 우리나라 제조업체의 실질적인 품질 경영활동과 경영성과간의 관계에 대하여 분석하였다. 본 연구는 기존의 대다수의 연구들이 취하던 품질경영의 성과측정에 그치지 않고 변수들간의 구조분석을 통하여 실제 어떤 활동이 성과에 주된 역할을 하는지에 대하여 살펴보았다. 실증분석결과 동기부여, 신기술개발등이 재무성과, 비재무성과에 공통적으로 큰 영향을 미치는 활동으로 확인되었다.

지하철 운행구간중 D철교 주변지역의 소음도 예측에 관한 연구

윤세철,오종민,이해경 경희대학교 환경연구소 1998 環境硏究 論文集 Vol.8 No.-

This study was carried out to predict and evaluate the outdoor noise levels around the D railway bridge of the subway line. The counter-measure for noise control was reviewed as the tunnel. The outdoor noise levels are generally calculated by subtracting sound transmission loss of the tunnel envelope from indoor noise levels. The coefficient of sound absorption of tunnel envelope was NRC 0.6 and sound transmission loss STC 23. Prediction of the noise levels around the D railway bridge was achieved by dividing the circumference into 10m×l0m regular grid spaces. The indoor noise levels at the tunnel ranged from approximately 45dB(A) to l07dB(A) and the outdoor noise levels 37dB(A) to 67dB(A) as peak sound level. In this study the maximum sound level at all locations around the subway line should not exceed 60dB(A) as energy equivalent sound level(Leq). As a result all points around the D railway bridge satisfied the noise level limit with the above tunnel.

성격의 변화를 수반한 Wilson씨병 1례

유세종,이상렬,박민철 圓光大學校 醫科大學 神經精神科學敎室 1994 圓光精神醫學 Vol.10 No.2

We had a 22 year old male patient with Wilson's disease showing neuropsychiatric symptoms. He showed neuropsychiatric symptoms such as personality change, regressed and childish behavior, wing-beating tremor and rigidity on the upper extrmity, open mouth, drooling, bradykinesia, dysarthria and dysphagia. In brain MRI findings, bilateral high signal intensity on T2WIs were observed in basal ganglia, thalamus, central midbrain and periaqueductal pons. In liver scan, splenomegaly was detected. At a slit-lamp examination, we detected the brownish colored pigments(Kayser-Fleisher ring) on Descement's membrain of both eye corneas. Laboratory findings were a low serum ceruloplasmin(2.63㎎/dl, normal: 25~45㎎/dl), low serum copper level(32㎍/dl, normal: 80~130㎍/dl), and an increased 24 hous urine-copper excretion level(258㎍/day, normal: 15~30㎍/day). Therefore, we diagnose the patient as having wilson's disease and we started medication treatment with penicillamine.

공동주택 바닥충격음 차단성능 평가

윤세철,오종민 慶熙大學校 地球環境硏究所 2002 지구환경논문집 Vol.13 No.-

In apartment buildings, floor-impact sound has been regarded as the major source which induces complaints from residents. It is mainly due to the use of light-weight structures and the lack of researches in terms of the sound transmission characteristics through the structures of a receiving room. The vibration produced by the impact on one part of an apartment building would travel as far as the other parts of structure only with with a little alleviation. As a result, the impact sound from upstairs has been regarded as a main source of noise causing discontentment among occupants. This study was carried out to measure the floor-impact sound levels and evaluate the insulation performance of floor-impact sound for the K apartment buildings which complaints induced and the newly-founded Y apartment buildings. The major results of this study are as followers; 1. The comparison showed that the light-impact sound levels and the levels of estimated light-impact sound ranged from 51.0dB to 73.9dB and 60dB to 66dB in the K apartment buildings, 50.2dB to 70.6dB and 57dB to 62dB in the Y apartment buildings. 2. The levels of estimated impact sound exceed the criteria of light-impact noise insulation 58dB by 6∼8dB and the criteria of heavy-impact noise insulation 50dB by 4∼6dB in the K apartment buildings and 4dB, 1dB in the Y apartment buildings, respectively.

외안각 절제술과 경결막 절개에 의한 안와 접근법

정종철,김성범,서지훈,송민석,전창훈,최세훈,김현민 대한악안면성형재건외과학회 2002 Maxillofacial Plastic Reconstructive Surgery Vol.24 No.4

Various surgical approaches to the orbits have been used. But the transconjunctival approach, also called the inferior fornix incision, provides adequate access to the orbital floor with esthetic results. Additionally, transconjunctival approach with lateral canthotomy allows more wide surgical field and good access to the orbital area. Generally, preseptal approach is more used rather than postseptal approach in the transconjunctival incision for the prevention of fat herniation during surgery. There are some complications in transconjunctival approaches but these complications can be prevented with careful surgical techniques. We report clinical results in 12 patients who were treated by preseptal transconjunctival incision with lateral canthotomoy for the treatment of orbital trauma. We were satisfied with this technique for reduction and reconstruction of the orbital trauma and we could also observe relatively good esthetic results.

요크셔테리어견에서 발생한 기능성 양측성 난소 과립막세포종

오승준,정성목,김명철 忠南大學校 獸醫科大學 附設 動物醫科學硏究所 2008 動物醫科學硏究誌 Vol.15 No.1

A 12-year-o1d, intact female Yorkshire terrier was presented with a vulvar enlargement and progressive vaginal discharge purulently for 3 weeks. On radiographic, ultrasonographic and computed tomographic evaluation, a large mass was detected in left upper abdomen which measured about 3x4 centimeters. And a lesser large mass was detected in right upper abdomen and it had several discrete anechoic follicles and large cysts. Moreover, an enlargement of uterus was detected in a caudal abdomen. The masses and the uterus were removed by complete ovariohysterectomy and the resected specimen was histopathologically examined. Based on the gross, histopathologic findings, and the hormonal test, the masses were definitely diagnosed as bilateral functional malignant granulosa cell tumor (GCT). Until now, the dog has been successfully managed more than 4 months without complications.

高張力鋼熱影響部 微視組織의 類別

鄭世喜,金台永,李聖哲 全北大學校 1979 論文集 Vol.21 No.-

The assessment of the toe HAZ fracture toughness is one of the most troublesome problems to resolve because the fracture toughness depends to a large extent upon microstructural gradients such as variations of the microstructure and the grain size in the HAZ and because such microstructural characteristics are directly influenced by the thermal cycle during welding. The aim of the present study is to classify metallurgically the distribution of the constituents of microstructure in the HAZ by measuring Vickers microhardness. The metallurgical observation and microhardness measurement for the toe HAZ of 60㎏/㎟ low alloy steel, which was submerged are welded as bead-on-plate, were carried out. The experimental results were summarized as follows; There is a linear relationship between the ratio of hardness Hv/(Hv)_M (Hv:Vickers hardness, (Hv)_M : Vickers hardness of 100% martensite) and the area percentage of their structural constituents, and it is independent on chemical composition of materials. It was concluded, consequently, that the transformation behavior for the structure of other 60㎏/㎟ low alloy steel in the HAZ and the ratio of mixture of structural constituents in its every position can be quantitatively classified by the ratio of microhardness Hv/(Hv)_M.