머리의 회전 속도와 시선 고정 거리, 머리 회전 방향에 따른 비디오두부충동검사에서의 전정안반사 이득의 변화

송찬일,김영은,차은혜,유명훈,이제연,박홍주 대한이비인후과학회 2015 대한이비인후과학회지 두경부외과학 Vol.58 No.8

Background and Objectives The conventional instrument for video head impulse test (vHIT) records the movement of the right eye only. The aim of this study was to evaluate the changes in the gain of vHIT results qdue to different directions of head rotation directons at different target distances and rotation speeds. Subjects and Method Horizontal head impulse was recorded by vHIT in 20 normal subjects. vestibulo-ocular reflex (VOR) gains to the right and left directions were compared at different test conditions. Two different impulses with low (50-150 deg/sec) and high (200-300 deg/sec) peak-head-velocities were tested and the subjects were also instructed to fixate a laser dot on a screen at different distances of 60, 100, and 200 cm. Eye movements were recorded on the right eye. Results Regardless of the target distances and peak-head-velocities, the VOR gains to the rightward head rotation were significantly greater than those to the leftward head rotation. In more than 85% of normal subjects, vHIT gain to the rightward head rotation was greater than that to the leftward head rotation. Mean gain asymmetries were 2.16-3.33% and the mean interaural vHIT gain differences were 0.04-0.07. Conclusion Regardless of the target distances and peak-head-velocities, the VOR gains to the rightward head rotation were significantly greater than those to the leftward head rotation. Directional asymmetry of VOR gain should be considered when interpreting vHIT results in patients with vestibular disorders.

架橋 Polyethylene의 Tree 發生機構에 關한 硏究

송찬일 조선대학교 에너지.자원신기술연구소 2002 에너지·자원신기술연구소 논문지 Vol.24 No.2

A tree can be formed by grounding the needle electrode after applying a considerably lower DC voltage than DC tree initiation voltage. The tree formed in this way will be called a grounding tree. As the AC voltage can be looked upon as repetition of charging and discharging, some similarity may exist between the mechanism of grounding tree initiation and the mechanism of AC tree initiation. And from the results of experiment, it is concluded that the tree initiation mechanism for superimposed voltage is similar to the grounding tree initiation mechanism.

2차측 능동크램프 방식의 영전압 영전류 스위칭 풀브리지 DC-DC 컨버터

송찬일,이상일,김병철 조선대학교 에너지.자원신기술연구소 2002 에너지·자원신기술연구소 논문지 Vol.24 No.2

The zero voltage switching(ZVS) full-bridge(FB) PWM dc-dc converter is characterized by high efficiency, low switching stress and simple topology. But because of primary current in the circulating period, conducting loss of the lagging leg device occur. In this paper, a novel zero voltage and zero current switching(ZVZCS) FB Phase-Shift(PS) PWM dc-dc converter was proposed. The converter has secondary auxiliary circuit using R, L, D. The proposed secondary auxiliary circuit is simple and lossless but removes the primary current for circulating period effectively. The 50kHz, 300W prototype converter was experimented for verification of the converter characteristics. The proposed converter has good characteristics of ZVZCS and high efficiency of 91%.

TiN이 증착된 SiO/TiN 박막의 전압-전류 특성

송찬일,김창석,정천옥,김병인 조선대학교 에너지.자원신기술연구소 2002 에너지·자원신기술연구소 논문지 Vol.24 No.2

In this study, the evaporation of SiO layers with different thickness on Si wafer(n-100) is conducted by using the RF sputtering method. Thin films are made with the structure of Si/SiO and Si/SiO/TiN by evaporating TIN which is used as a diffusion barrier of non-resistant superintegrated semiconductor circuit. The research is performed to increase the I-V characteristics depending upon the SiO thickness and the reliability and reproducibility of the TIN thin film. It is shown that, since the TIN is diffused into SiO surface and fosters the potential barrier highly in the SiO/TiN thin film, the saturation voltage appears after the SiO thin film does. The thicker the SiO film becomes, the weaker the current variation does and the less leakage current the TiN deposited thin film has. The leakage current variation with a little slope is found in the negative voltage zone due to the effect of the trap state density near the electrode. The spiking which occurs when the film is too very thin can be reduced by adding TiN. The stability can be obtained due to no pervasion of A1 into SiO. The experimental result matches the Ohm s law and satisfies the equation of current.

2차측 능동크램프 방식의 영전압 영전류 스위칭 풀브리지 DC-DC 컨버터

송찬일,이상일,김병철 조선대학교 에너지.자원신기술연구소 2001 에너지·자원신기술연구소 논문지 Vol.23 No.2

The zero voltage switching(ZVS) full-bridge(FB) PWM dc-dc converter is characterized by high efficiency, low switching stress and simple topology. But because of primary current in the circulating period, conducting loss of the lagging leg device occur. In this paper, a novel zero voltage and zero current switching(ZVZCS) FB Phase-Shift(PS) PWM dc-dc converter was proposed. The converter has secondary auxiliary circuit using R, L, D. The proposed secondary auxiliary circuit is simple and lossless but removes the primary current for circulating period effectively. The 50 kHz, 300 W prototype converter was experimented for verification of the converter characteristics. The proposed converter has good Characteristics of ZVZCS and high efficiency of 91%.

차량용 교류발전기의 소음 특성에 관한 연구

송찬일,송상기,송각기 조선대학교 에너지.자원신기술연구소 2002 에너지·자원신기술연구소 논문지 Vol.24 No.2

Automobile alternator noises are composed of mechanical noise, ventilation noise and magnetic noise. The design of magnetic parts, fans, bearing, and the rotor has an effect on these noises. In running automobile alternator, these elements can generate noises and vibrations. To know the noise sources of the various alternator, the characteristics of noises are analyzed as rotating speed is increased. Also, this study analyze the harmonics of the noise for the various alternators. The results of this study can lead the instruction t o the noise reduction on the automobile alternator.

雙計-平板 gap의 코로나 펄스 特性에 관한 硏究

송찬일 조선대학교 에너지.자원신기술연구소 2002 에너지·자원신기술연구소 논문지 Vol.24 No.2

This paper presents the obtained ecperimental results of a research program aimed to study corona on rough surfaces. This paper models the interaction between positive coronas using sewing needles attached to a thick conductor of smooth surface. The experimental research is focused on stundying of discharge ; namely the onset and offset voltages of the pulse mode. The obtained results will be analysed and the transition from burst pulses to continuous glow in labolatory air is discussed.

SF_(6)의 Impulse 破壞電壓-時間特性에 對한 硏究

宋燦日 조선대학교 에너지.자원신기술연구소 2002 에너지·자원신기술연구소 논문지 Vol.24 No.2

In this paper the impulse breakdown voltage-time characteristics of coaxial cylinder gaps in SF_(6) are experimentally and theoretically investigated. The factors influencing the voltage-time curve that are systematically studied in this paper include the nature and pressure of the gas and the polarity of the impulse applied to the high voltage electrode. The breakdown time delay probability is treated as a bivariate distribution in statical and formative time lags. A systematic method is developed to relate the statistics of breakdown delays in SF_(6) with their breakdown voltage-probability.

Ga_(0.6)Sb_(1.4)Se₃單結晶의 光傳導度 特性

宋燦日,劉炳守,李愚宣,金南伍,金亨坤 조선대학교 에너지.자원신기술연구소 2002 에너지·자원신기술연구소 논문지 Vol.24 No.2

Ga_(0.6)Sb_(l.4)Se₃single crystals were grown by the Bridgman technique method, These single crystals had orthorhombic structure, and lattice constant and electric conduction type of Ga_(0.6)Sb_(l.4)Se₃single crystals was a = 11.860Å , b = 12.057Å, c = 4.103Å and p-type, respectively. Direct band gap of Ga_(0.6)Sb_(l.4)Se₃single crystals obtained from optical absorption spectrum were 1.17 eV. Photoconductivity spectrum measured at 10K showed that the photoconductivity peak in Ga_(0.6)Sb_(l.4)Se₃single crystals was located in 960 nm.

고막 천공 없이 발생한 중이 콜레스테롤 육아종

송찬일,윤태현 대한이비인후과학회 2014 대한이비인후과학회지 두경부외과학 Vol.57 No.12

Cholesterol granuloma is a histopathologic term used to describe the giant cell reaction to cholesterol deposits that occurs in sequestered, fluid-filled air cells that are normally pneumatized compartments of the temporal bone. It is a benign lesion which is known to be found in the middle ear cavity, mastoid air cells and petrous apex. Although cholesterol granuloma is a pathologic term describing a tissue response to cholesterol crystals, it is now recognized as a clinical disease entity especially in cases of unilateral blue eardrum without tympanic membrane perforation. Three factors are considered to play an important role in the development of cholesterol granulomas: obstruction of ventilation, microhemorrhage, and impaired drainage. Cholesterol granulomas are often found as pathologic lesions like granulation tissue in the middle ear and mastoid cavities during middle ear surgeries in patients with chronic otitis media or cholesteatoma. Cholesterol granulomas of the middle ear typically present as conductive hearing loss and a blue eardrum, whereas those at the petrous apex are incidentally identified or manifest as bony erosion with sensorineural hearing loss, tinnitus, vertigo, or cranial nerve impairment. Cholesterol granulomas in middle ear cavity and mastoid air cells are related with Eustachian tube dysfunction, so initial treatment of cholesterol granuloma is the insertion of ventilation tube in many cases. However, it is often necessary for the complete cure to do excision of the lesion through tympanomastoidectomy surgery. Korean J Otorhinolaryngol-Head Neck Surg 2014;57(12):809-14