• Korean Journal of Optics and Photonics
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• v.18 no.1
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• pp.19-23
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• 2007

We derived analytically the generalized curvature linear equation useful in the initial optical design of a two-mirror system with finite object distance, including an infinite object distance from paraxial ray tracing and Seidel third order aberration theory for coma coefficient. These aberration coefficients for finite object distance were described by the curvature, the inter-mirror distance, and the effective focal length. The analytical equations were solved by using a computer with a numerical analysis method. Two useful linear relationships, determined by the generalized curvature linear equations relating the curvatures of the two mirrors, for the cancellation of each aberration were shown in the numerical solutions satisfying the nearly zero condition ($<10^{-10}$) for each aberration coefficient. These equations can be utilized easily and efficiently at the step of initial optical design of a two-mirror system with finite object distance.

• Journal of Korean Ophthalmic Optics Society
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• v.11 no.2
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• pp.77-83
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• 2006

We have studied the astigmatism according to the bevel position and the tilting(pantoscopic) angle of decentered spectacle lens for prism prescription. For prism prescription, generally we make a general spectacle lens into decentered spectacle lens. At this time the bevel position of decentered lens is a important matter, because the difference between optic axis and visual axis occur aberrations. Using the calculation we find that the case that the axis of bevel rotation band passes the front curvature center of (+) lens has a smaller astigmatism than the case that the axis of bevel rotation band passes the rear curvature center of (+) lens and that the case that the axis of bevel rotation band passes the rear curvature center of (-) lens has a smaller astigmatism than the case that the axis of bevel rotation band passes the front curvature center of (-) lens. We find the lens with higher refraction index has a smaller astigmatism.

• Clinical and Experimental Pediatrics
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• v.55 no.12
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• pp.487-490
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• 2012

We report a case of isodicentric chromosome 15 (idic(15) chromosome), the presence of which resulted in uncontrolled seizures, including epileptic spasms, tonic seizures, and global developmental delay. A 10-month-old female infant was referred to our pediatric neurology clinic because of uncontrolled seizures and global developmental delay. She had generalized tonic-clonic seizures since 7 months of age. At referral, she could not control her head and presented with generalized hypotonia. Her brain magnetic resonance imaging scans and metabolic evaluation results were normal. Routine karyotyping indicated the presence of a supernumerary marker chromosome of unknown origin (47, XX +mar). An array-comparative genomic hybridization (CGH) analysis revealed amplification from 15q11.1 to 15q13.1. Subsequent fluorescence in situ hybridization analysis confirmed a idic(15) chromosome. Array-CGH analysis has the advantage in determining the unknown origin of a supernumerary marker chromosome, and could be a useful method for the genetic diagnosis of epilepsy syndromes associated with various chromosomal aberrations.

• The Korean Journal of Physiology
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• v.19 no.2
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• pp.189-202
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• 1985

Enhanced activity of renin-angiotensin-aldosterone system has been suggested as a cause of the high blood pressure in certain forms of experimental hypertension. In spontaneously hypertensive rats, however, increased activity of the system has not been found, and even suppressed renin angiotensin system has been reported in the spontaneously hypertensive rat. In the present experiments it was attempted to explore the possible alteration of the short loop negative feedback control in the hypertensive rat. Experiments have been done in the anesthetized spontaneously hypertensive rats(SHR) as well as in normotensive Wistar and Sprague Dawley rats as control. Responses of the plasma renin activity to the intravenous L-isoproterenol were dose dependent, in both SHR and normotensive control rats. Hypotensive responses to smaller do sea of L-isoproterenol were more accentuated in SHR than in the normotensive control rats. Angiotensin If given intravenously suppressed plasma renin activity in a dose dependent fashion in both groups. However, these suppressive responses were significantly attenuated in SHR as compared with the normotensive control rats. Treatment with angiotensin I-converting enzyme inhibitor did not correct the attenuated responses of the plasma renin activity to angiotensin II in SHR. Intravenous infusion of arginine vasopressin also produced a dose-dependent suppression of plasma renin activity in both groups. The responses to arginine vasopressin were also significantly attenuated to the normotensive control rats. In the sodium-depleted SHR, arginine vasopressin did not suppress plasma renin activity, whereas the suppressive responses to arginine vasopressin in the normotensive control rats were not different from the untreated control rats. These data suggest that there may be a derangement in the short loop negative feedback control of the renin-angiotensin system in spontaneously hypertensive rat.

• Journal of the Semiconductor & Display Technology
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• v.15 no.3
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• pp.62-66
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• 2016

Optical system needs to be aligned before its undergoing process, is usually shows coma aberrations, which occurred due to imperfection in the lens or other components results in off-axis point sources, appearing to have a tail like a comet. There are some methods to correct coma aberration. In this paper, to correct coma aberration in optical system, using a robot arm type coordinate measuring machine(CMM). CMMs are widely used to measure the form of accuracy of parts and positioning accuracy of systems. Among them, robot arm type CMM has more advantages than the others, such as its mobility and measuring range. However, robot arm type CMM has lower accuracy than cantilever type CMM. To prove robot arm type CMM's accuracy, several factors were suggested in this paper and the final measuring results were compared to a commercial cantilever type CMM. Based on this accuracy, a typical optical system was successfully aligned by using our robot arm type CMM.

• Korean Journal of Optics and Photonics
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• v.16 no.1
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• pp.34-42
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• 2005

This paper presents the optimum initial design containing the first and third order properties of the three-group zoom system using lens modules, and the real lens design of the system. The optimum initial design with focal length range of 4.3 mm to 8.6 mm is derived by assigning appropriate first and third order quantities to each module along with the specific constraints required for the system. An initial real lens selected for each group has been designed to match its focal length and the first orders into those of the each lens modules, and then combined to establish an actual zoom system by adjusting the air space between the groups at all zoom positions. The combination of the separately designed groups results in a system which satisfies the first order properties of the zoom system composed of the original lens modules. As a result, by residual aberration correction, we could obtain a zoom system useful in compact digital zoom cameras and mobile phone cameras employing the rear focus method.

• Korean Journal of Optics and Photonics
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• v.17 no.2
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• pp.113-119
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• 2006

We need a good image of the retina of the human eye in order to inspect or cure it. In this work, an optical system design for a retinal camera is studied and the finite schematic eye model made by Sang Gee Kim and Sung Chan Park is used. The optical system is composed of four lens groups. The rays of the entire object field are collected on the center by the 1st group and the objective is imaged by all the other groups. The image is detected by the CCD array and displayed by a monitor The 1st lens group is employed singlet and other groups are employed triplets. Ray aberrations, spot diagrams, diffraction line spread functions and MTFs are calculated for optical performance assessment. This design may be very useful for the development of a retinal camera with high performance.

• Journal of Genetic Medicine
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• v.13 no.2
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• pp.95-98
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• 2016

We report the prenatal diagnosis of an unbalanced translocation between chromosome Y and chromosome 15 in a female fetus. Cytogenetic analysis of parental chromosomes revealed that the mother had a normal 46,XX karyotype, whereas the father exhibited a 46,XY,der(15)t(Y;15) karyotype. We performed cytogenetic analysis of the father's family as a result of the father and confirmed the same karyotype in his mother and brother. Fluorescence in situ hybridization and quantitative fluorescent-polymerase chain reaction analysis identified the breakpoint and demonstrated the absence of the SRY gene in female members. Thus, the proband inherited this translocation from the father and grandmother. This makes the prediction of the fetal phenotype possible through assessing the grandmother. Therefore, we suggest that conventional cytogenetic and molecular cytogenetic methods, in combination with family history, provide informative results for prenatal diagnosis and prenatal genetic counseling.

• Restorative Dentistry and Endodontics
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• v.25 no.1
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• pp.78-84
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• 2000

The aim of this study was to compare shaping ability of nickel-titanium rotary files with different taper in simulated resin canals. The instruments used in this study were GT with .04 taper ProFile with ISO-sized tip, .04 taper ProFile with ISO-sized tip alone, and .02 taper Naviflex file and all canals were prepared by crown-down technique. A total of 30 composite images were made from pre- and post-canal scanned images using Scanjet 4C scanner and Corel photopaint 8.0 and then, prevalence of canal aberrations was measured. The amount of coronal substance the instruments removed was also calculated two-dimensionally on digitized images with the Brain C software to compare the relative enlarging efficiency. Finally, the prepared internal canal form was evaluated three-dimensionally with impression technique. The results were as follows; 1. The incidence of zipping in Naviflex group was significantly high compared to the other two groups(P<.05). 2. The amount of coronal substance the GT combined group removed was significantly larger than the other two groups(P<.05). 3. The GT combined group produced canals with good taper and flow. Under the conditionas of this study, the combined use of larger tapered nickel-titanium rotary files prepared simulated canals safely, efficiently and with good three-dimensional form.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.57-57
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• 2007

Aspheric glass lenses have many optical advantages, for glass have superior optical performance and an aspheric form can reduce optical aberrations. Recently, the use of it is rapidly expanding as the mass production becomes possible by glass molding press and so this method is considered as the best method for fabricating an aspheric glass lens, but it is difficult to control many parameters for pressing and cooling process. Design of experiments (DOE) is a very useful tool to design and analyze complicated industrial design problems. This study investigated the pressing conditions to mold aspheric glass lenses for mega pixel phone camera module using DOE method. We have applied fractional factorial design and the response variable was set form accuracy (PV) of aspheric surface of molded lens. The results of analysis indicates that all factors expect for pressing force of each step are available for the form accuracy (PV). It was the optimum condition of the designed pressing conditions for lowering the form accuracy(PV) value of molded lens that all factors were at the low level. The form accuracy (PV) of mold and molded lens under the optimum condition are $0.85\;{\mu}m$ and $0.922\;{\mu}m$ respectively.