특별초청강의 : 맞춤형 시력교정 연구(Customized Vision Correction)

박성종 한국안광학회 2007 논문집 Vol.2007 No.2

단락된 가우스 광이 광학 디스크 재생 신호에 미치는 영향

박성종,정창섭 한국광학회 1996 한국광학회지 Vol.7 No.4

To investigate influence of the incident beams which have the truncated Gaussian amplitude and of the shapes of bump on read-out signal is an optical disc, and the point spread function on bump, the scalar diffraction theory is used in this paper. We consider the truncated Gaussian amplitudes which are $\sigma$=0, 0.5, 1.5, and 2.5, the height of bump which is given by $n{\Delta}_0={\lambda}/4$, and the phase height of bump which is then given by ${\Phi}_0={\pi}$. We also consider the shapes of the bump which are a rectangular shape, a frustoconical shape, and a conical shape. It is shown that as the truncation of incident beam reduces the radius of central spot on bump decreases, the maximum value of read-out signal increases, and that the size of bump decreases. From these results, we get better read-out signal and the reduced cross-talk in optical disc when the truncation of incident beam reduces. Therefore a laser beam having less truncated Gaussian amplitude may useful for an actual optical disc.

속도군 선택 광펌핑 분광학

박성종,조혁,이호성,Park, Sung-Jong,Cho, Hyuck,Lee, Ho-Seong 한국광학회 1997 한국광학회지 Vol.8 No.5

We performed the velocity selective optical pumping(VSOP) spectroscopy using the rubidium atomic vapor in the room temperature. This spectroscopic technique removes the Doppler broadening by both optical pumping effect and the selection of atoms with a particular velocity. In this experiment, we used two independent lasers; one was a locked laser whose frequency was fixed and the other was a sweep laser whose frequency was tunable. The two beams were passing through the sample in the same direction unlike the conventional VSOP spectroscopy using two counter-propagating beams. We could make the velocity selective range of atoms much wider with this method than the old one.

Shaded apodizer가 광학 디스크 시스템의 wotodf 신호에 미치는 영향

박성종,심상현 한국광학회 1999 한국광학회지 Vol.10 No.6

To investigate the effect of a shaded apodizer on the read-out signal in an optical disc system, we consider the is apodizer in which the amplitude transmittance decreases gradually from the center of pupil toward its edge and the iH apodizer in which the amplitude transmittance increases gradually from the center of pupil toward its edge, using the scalar diffraction theory. We also consider the bump shapes which are a cylindric, a semi-conic, and a conic bump, and bump height which is given by $\lambda/4$ and occurs to the phase change $(\pi)$). The read-out signal of is apodizer increases from S = 0 upto maximum value, and then decreases for increasingly larger values of bOo While the iH apodizer has two maximum values. When an optical disc system has a spherical aberration $(W_{40}=0.5\lambda)$, the maximum read-OUt signal of is apodizer is higher than that of iv apodizer which has no apodizer.odizer.

대손충당금 분류조정을 이용한 상호저축은행의 이익관리; 특별대손충당금을 중심으로

박성종,정준희,조석희,기도훈 예금보험공사 2019 金融安定硏究 Vol.20 No.2

This study examines earnings management method of savings banks which serve as representative financing institution for people with poor credit. Because regulatory and supervisory regulations of savings banks are different to those of commercial banks, managers of savings banks may reflect these characteristics in earnings management method. Especially, managers of the savings bank are expected to choose the earnings management method considering resulting costs and benefits such as effects on BIS ratio, discretion of loan assets classification, and the magnitude of earnings management. Empirical evidence indicates that savings bank discretionarily exploit classification of loans assets to smooth earnings. Specifically, managers discretionarily classify loan assets items upwards or downwards within non-performing assets. In addition, savings banks with BIS ratio lower than 7% tend to manage earnings upwards by classifying loan assets items upwards within non-performing assets to increase both net income and BIS ratio. The results of study imply that limitation of present regulatory and supervisory rules on savings banks incurs unintended negative effects on agency problem 본 연구는 상호저축은행이 특별대손충당금의 분류조정을 이용하여 이익을 조정하는지를 살펴보았다. 상호저축은행은 일반(상업)은행과 달리 고정여신에 대한 충당금을 일부 자본으로 인정받는다. 상호저축은행이 위 규정을 이용하여, 특별대손충당금의 분류조정을 통해 이익관리 및 자본관리를 수행하는지 살펴보았다. 이를 검증하기 위하여 대손충당금 전입액을 일반대손충당금과 특별대손충당금으로 구분하고 대손충당금과 대손충당금 전입 및 법인세 전 이익과의 관련성을 살펴보았다. 실증분석결과 저축은행은 이익을 유연화하기 위하여 대출자산 항목의 분류조정을 이용하는 것으로 나타났다. 구체적으로, 상호저축은행은 고정이하여신 내 분류조정을 이용하여 특별대손충당금 전입액을 조정하여 이익을 유연화하고 있다. 재무건전성이 취약한(BIS 7% 미만) 저축은행의 경우에는 특별대손충당금 전입액을 이용한 이익조정을 더 많이 하는 것으로 나타났다. 이러한 결과는 저축은행의 고정여신의 충당금을 자본으로 인정하는 현행 제도의 수정보완이 필요함을 시사한다.

MOT에서 좌표의존 비대칭 광압에 의한 루비듐 원자의 운동과 원자 구름 분포

박성종 한국광학회 2000 한국광학회지 Vol.11 No.4

We observed the spatial distributions of atom in a magneto-optical trap. These distributions include sphere, stick, ring, ring with core, sphere-sphere, sphere-ring etc. Coordinate-dependent asymmetry radiation force (CDARF) that arises due to laser beams misalignment and transverse profile of the laser beams is exerted on atoms, and the shape of trapped cloud is changed with the misalignment parameter. We use equations of motion that takes into account the Zeeman sublevels of the 87Rb atom, magnitude and direction of magnetic field, polarization of trapping lasers, and transverse profile of the laser beams. A theoretical analysis of the equation of motion for the trapped atom explained all the experimental observations.

광원 및 디스플레이 기기의 색특성 측정의 불확도 평가

박성종,이동훈,김용완,박승남,Park, Seong-Chong,Lee, Dong-Hoon,Kim, Yong-Wan,Park, Seung-Nam 한국광학회 2009 한국광학회지 Vol.20 No.2

This work introduces the uncertainty evaluation formulation on color measurement of light sources and display devices, such as CIE 1931 (x, y) chromaticity, CIE 1960 (u, v) chromaticity, correlated color temperature, and distribution temperature. All the mentioned quantities are reduced from spectral data in the visible range, for which uncertainties are strongly correlated between different wavelengths. Using matrix algebra we have formulated the uncertainty propagation from the SI- traceable spectral irradiance standard to the individual color related measurement quantities taking the correlation between wavelengths into account. As a result, we have demonstrated uncertainty evaluation examples of 3 types of light sources: CIE illuminant A, LED white light, and LCD white light. This method can be applied to any other quantities based on spectral measurement such as solar irradiance, material color measurement, etc.

외상 후 스트레스 장애 동반 여부에 따른 정신분열병 환자의 임상증상과 치료효과의 비교 : 1년간의 전향적 추적연구

박성종,김남희,정재열,이선이,Park, Sung-Jong,Kim, Nam Hee,Jeong, Jae-Yeol,Lee, Sunny 대한생물정신의학회 2009 생물정신의학 Vol.16 No.4

Objectives : The aims of this study were to assess a) the prevalence of trauma and posttraumatic stress disorder(PTSD) in schizophrenic patients and b) the differences in symptomatology and outcome after 1year treatment between those with and without PTSD. Methods : Twenty eight schizophrenia and schizoaffective disorder patients completed the Positive and Negative Syndrome Scale(PANSS), Life Stressor Checklist-Revised(LSCL-R), Clinician-Administered PTSD Scale(CAPS), Dissociative Experiences Scale(DES), Hamilton Psychiatry Rating Scale for Depression(HAM-D), and Rosenberg Self-Esteem Scale(RSE). Results : Twenty six patients(92.9%) had at least one trauma in their life time. Eleven patients(39.3%) were diagnosed with PTSD. PTSD group had significantly higher scores on HAM-D and DES but lower scores on RSE. PTSD group also had significantly lower score in the baseline PANSS Negative score. Higher CAPS scores were significantly correlated with lower baseline PANSS Negative score and greater change after 1year of PANSS Negative score. Conclusion : These results showed that the prevalences of trauma and PTSD are high in schizophrenic patients and suggested that PTSD and trauma-related symptoms affected the symptomatology and treatment outcome. More research is warranted to better understand the effects of PTSD in schizophrenic patients.

Defous에 따른 bessel beam의 회절 특성

박성종,최기준,박민경,김재범,심상현,정창섭 한국광학회 1995 한국광학회지 Vol.6 No.2

To investigate the diffraction property of the Bessel beam for defocus which acts CFAP (Combined Filter of Amplitude and Phase), we calculated numerically the intensity, the radius of central spot, and the optical transfer function for the number of node of the Bessel beam when an optical system has an aberration-free or a spherical aberration. The Bessel beam has larger the maximum intensity and the OTF value for an optical system with a spherical aberration than that with an aberrationfree. Particularly, the OTF value at the point of maximum intensity for $W_{40}=3\lambda$is higher for the Bessel beam than for the Clear aperture. From these results, we know that the Bessel beam has the compensating effect. The Bessel beam also has the radius of central spot having a superresolution. We will useful for the fabrication of semiconductor device and the optical recording system using these effects.ffects.

Amplitude Filter와 Phase Filter가 결합된 광학계의 결상특성

박성종,이종진,정창섭 한국광학회 1993 한국광학회지 Vol.4 No.1

We chose Bessel beamu[$J_o(ar)}$)l in order to investigate image forming property of the optical system with combined filter of amplitude and phase(CFAP). This paper investigated numerically the influence of number of nodes of these beams on the PSF, encircled energy(E), transmission ratio(TR), gain((;) for an aberrated(1aberration-free) optical system. These results showed that the property of PSF differ considerably from the one of the existing amplitude filter and that Bessel beam has super compensating effect for an optical system with spherical aberration. Particularly, the Bessel beam has less the size of central spot than the radius of Airy disk, this result can therefore be applied to the fabrication of semiconductor device.