Chlorhexidine과 fluoride 성분의 varnish가 타액 내 mutans streptococci 수에 미치는 효과

서정아,김재곤,백병주,양연미,이용희,김상훈 大韓小兒齒科學會 2004 大韓小兒齒科學會誌 Vol.31 No.4

본 연구의 목적은 chlorhexidine(Cervitec)과 fluoride(Fluor-protector) 성분을 각각 포함한 varnish를 치아에 적용하였을 때 타액내의 mutans streptococci의 수의 감소에 미치는 효과를 알아보기 위한 것이다. 전북대학교 치과대학생 40명을 대상으로 하여 mutans streptococci 균종 수를 평가하였으며, 이들을 무작위로 네 군으로 나누어 다음과 같이 varnish를 적용하였다; A) varnish를 적용하지 않은 군(n=10), B) chlorhexidine varnish 적용군(n=10), C) fluoride varnish 적용군(n=10), D) chlorhexidine과 fluoride varnish를 모두 적용한 군(n=10), Mutans streptococci 수 측정에는 Orion diagnostica 사의 Dentocult SM을 사용하였다. Varnish를 적용하지 않은 상태에서 1차로 Mutans streptococci 수를 측정한 후 각각의 varnish를 적용하였으며, varnish 적용 12주 후 다시 측정하여 기록하였다. 모든 실험군(group B, C, D)에서 12주 후에 측정한 Mutans streptococci 수가 감소한 개체가 증가한 개체보다 많았으나 통계적으로 유의한 차이는 보이지 않았다(p>0.05). 실험에 사용된 어떠한 varnish도 적용 12주 후에 타액 내 mutans streptococci 수에 통계적으로 유의할 만한 변화를 주지는 못하는 것으로 나타났다(p>0.05). The objective of the present prospective trial was to compare the efficacy of chlorhexidine(Cervitec), Fluoride(Fluorprotector) and combination of chlorhexdine and fluoride varnishes in decreasing the level of salivary mutans streptococci. Forty healthy students of school of dentistry, Chonbuk national university were investigated to evaluate mutans streptococci(MS) counts and randomized into four groups to treat with the experimental varnishes: A) untreated group(n=10), B) chlorhexidine group(n=10), C) fluoride group(n=10), D) chlorhexidine and fluoride group(n=10). Dentocult SM^(�)(Orion Diagnostica) strip method was used for measurement of the level of mutans streptococci in saliva. Stimulated saliva were collected at baseline for mutans streptococci counts evaluation(ms1), 12 weeks later the completion of each varnish treatment, mutans streptococci counts were re-evaluated. In varnish group with chlorhexidine, fluoride and combination of chlorhexidine and fluoride, the level of mutans streptococci was lower after 12 weeks than at baseline, but there were no significant differences in saliva(p>0.05), when compared with baseline. After 12 weeks, a remarkable reduction was still found in the subjects with high level of mutans streptococci at baseline, but not different in the low and moderate level of mutans streptococci(p>0.05).

영역분류를 이용한 블록화 현상 감소 기법

서용수,김중곤,김우열 東西大學校 2000 동서논문집 Vol.6 No.-

본 논문에서는 DCT(Discrete Cosine Transform)를 기반으로 정지영상을 압축한 후 복원된 영상의 블록화 현상을 감소시키기 위한 방법을 제안하였다. 제안한 블록화 현상 감소기법은 BCT 계수의 특성에 따라 단순영역과 복잡영역으로 분류한 후 분류된 영역에 따라 서로 다른 양자화 테이블을 적용시켰다. 인간시각 특성상 블록화 현상이 잘 나타나는 평탄영역과 단순에지 영역은 저주파 영역의 양자화 요소값을 작게 하여 블록화 현상을 감소시키고, 복잡 영역에서는 블록화 현상이 눈에 잘 나타나지 않기 때문에 양자화 요소값을 증가시켜 비트발생률을 줄일 수 있도록 하였다. 제안한 블록화 현상 감소 기법의 타당성은 컴퓨터 모의실험을 통하여 확인하였다. In this paper, we proposed a method of reducing blocking effects in reconstructed image that was compressed on DCT(Discrete Cosine Transform). The proposed blocking effects reduction techniques use difference quantization table according to region classification such as simple and complex region. The regions are classified by the characteristics of DCT coefficient. In flat and simple edge region, where blocking effects are more visible, we use small valued quantization table to reduce blocking effects. For complex region, blocking effects are less visible, we use large valued quantization table to reduce generated bit rate. Computer simulation results show that blocking effects of proposed method is reduced that of conventional method.

원격감지 영상의 콘트라스트 향상

서용수,김중곤 東西大學校 2001 동서논문집 Vol.7 No.-

In this paper we discussed the processing procedures of histogram equalization(HE) method and brightness preserving hi-histogram equalization(BBHE) method in the contrast enhancement methods for the performance comparison. With remotely sensed image data of Landsat TM we compared the performances of four methods about Min-Max method, ± 1SD method, HE method, BBHE method. The simulation results demonstrate that the HE method and BBHE method are more effective in the contrast enhancement performances than the Min-Max method and ± 1SD method. In the HE method the mean brightness of the resultant output images approached to the middle gray level with regardless of input image mean. In the BBHE method, it is capable of preserving the mean brightness of a input image compared to the HE method while enhancing the contrast of input image effectively. Thus it is provided more natural enhancement effect than the HE method.

경계 방향 특성을 이용한 변위추정 기법

서용수,김중곤 東西大學校 2001 동서논문집 Vol.7 No.-

In this paper, we propose an efficient block based disparity estimation method which use the disparity vector of spatially adjacent blocks and edge orientation characteristics for the stereoscopic image. The proposed disparity estimation method calculates initial disparity vector at first, and then the final disparity vector is obtained by the full search disparity estimation for small search region. The method can obtain smoothed disparity vector in smooth region and can obtain a small error in the simple edge and texture region. An additional feature of this method is that its computational load decreased for calculating the disparity vector on account of estimating initial disparity vector and searching for smaller region. The simulation results demonstrate that disparity vectors are smoothed and PSNR is close to the one of full search.

지능화 진단 시스템개발을 위한 광바이오 텔레미트리 칩 제작

서희돈,박차훈,배용욱,최세곤 嶺南大學校 工業技術硏究所 1997 工業技術硏究所論文集 Vol.25 No.1

In this paper, we fabricated optical telemetry IC chip using CMOS process. The telemetering IC with the size of 4 ×4㎟ has the following functions: receiving of command signals, initialization of internal state of all functional blocks, decoding of subject-selection signal, time multiplexing of 4-channel modulated physiological signals, transmission of telemetry signal to extemal system, and auto power down control. The designed synchronous oscillator with low supply voltage dependence operates at a supply voltage from 4.6V-6.0V. And the nonlinearity error of PIM modulator was less than 1.2%FS. In order to demonstrate the principle operations of the implemented CMOSIC chip, the experiments of biotelemetry was performed by telemeter unit and external unit. Main features of this system are to select one of the 4 subjects, to enable measurement of biological signals using the same optical signal, and transmit them back to the extemal unit.

부울함수의 논리곱의 배타적 합 논리로의 간략화

이상곤,이진흥,서용수 東西大學校 1998 동서논문집 Vol.4 No.-

In this paper, a Boolean function minimization algorithm in the form of exclusive-or sum of products(ESOP) is proposed Since Boolean furctions expressed as the ESOP are convenient to determine the structural equivalence among functions, they may be used in developing Boolean functions for hash function.

생체신호처리용 ASIC 칩 개발

배용욱,박차훈,서희돈,최세곤 경북대학교 센서기술연구소 1998 센서技術學術大會論文集 Vol.9 No.1

The biotelemetry system transmits monitored physiological signal from multiple subjects to an electrical instrument at remote place where this information can be observed via electrical or optical link. In this paper, we developed an optical linked telemetry system which can transmit 6-channel physiological signals from 4 subjects, simultaneously. The proposed telemetry system is fabricated with Altera FPGA chip(EPM7128LC84-20) and 0.8μm CMOS n-well process technology. We designed a All-Digital PLL to synchronize with the external measurement system which consisted of a command signal transmitter and a telemetry signal demodulator. The operation characteristic of a All-Digital PLL is superior than an enforced synchronization oscillator which consisted of negative elements and a comparator. The required time to synchronize with a external measurement system at the maximum phase error is about 10.3ms. The novel external measurement system is implemented with Altera FPGA chip (EFM7096LC84-15).

Inpatient cardiac rehabilitation programs’ exercise therapy for patients undergoing cardiac surgery : National Korean Questionnaire Survey

Yong Gon Seo,Mi Ja Jang,Won Hah Park,Kyung Pyo Hong,Jidong Sung 한국운동재활학회 2017 JER Vol.13 No.1

Clinical outcomes of inpatient cardiac rehabilitation for patients with treated left ventricular assist device in Korea : 1-year follow-up

Yong Gon Seo,Won Hah Park,SuKi Oh,Jidong Sung,Eun Seok Jeon,Jin Oh Choi,Jae K. Oh,Yun Hee Kim,Ho Young Kim,Mi Ja Jang,Nam Gyung Choi,Yang Hyun Cho 한국운동재활학회 2019 JER Vol.15 No.3

Milliwatt-class non-polar a-plane InGaN/GaN light-emitting diodes grown directly on r-plane sapphire substrates

Yong Gon Seo,Kwang Hyeon Baik,송근만,Seokwoo Lee,윤형도,Jae-Hyoun Park,오경환,Sung-Min Hwang 한국물리학회 2010 Current Applied Physics Vol.10 No.6

Non-polar a-plane (1120) light-emitting diodes (LEDs) in InGaN/GaN multiple quantum well structures were successfully fabricated by metal organic chemical vapor deposition (MOCVD) directly grown on r-plane (1120) sapphire substrates. The full width at half maximums (FWHMs) of the X-ray rocking curve (XRC) of an a-plane GaN template along the c- and m-axes were measured to be ~349 and ~533 arcsec,respectively. The optical output power and external quantum efficiency (EQE) at drive currents of 20 mA and 100 mA under direct current operation in on-wafer measurements were 1.24mW, 2.4% and 100 mA,1.7%, respectively. The a-plane LED showed 2.8 nm blue shift with change in drive current from 5 mA to 100 mA. The polarization ratio at room temperature was 0.4 and it indicates that the a-plane LED has polarization anisotropy.