• Korean Journal of Optics and Photonics
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• v.10 no.6
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• pp.443-447
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• 1999

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.

• The Korean Journal of Zoology
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• v.34 no.4
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• pp.433-451
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• 1991

척추동물(7목 23종)의 췌장에서 insulin( B)세포, glucagon(A)세포, somatostatin( D)세포 및 pancreatic polypeptide( PP)세포 등을 면역세포화학법으로 동정하여 이들의 출현율, 분포양상 및 형태 등을 계통별로 비교하였다. 파충강의 거북목, 양서강의 유미목 및 어강의 악상대목 들을 제외한 모든 종에서 췌도의 형성을 관찰할 수 있었으며, 췌도를 구성하는 내분비세포의 크기에는 계통간의 차이가 있었다. B세포는 파충강의 것이 가장 크고, 양서강, 어강의 순이 었으며 A와 PP세포는 양서강, 파충강 및 어강의 순서였다. D세포는 양서강의 것이 가장 윤고, 다음이 어장이었으며, 파충강의 것이 가장 작았다. 이들 세포의 모양은 B세포의 경우 양서강과 어장에서는 원형, 난원형 및 방추형이었으며, 파충강에서는 원추형 및 단기형 등 다양한 모습이었다. A세포는 어강에서는 원헝, 난원형 및 방추형이 고르게 나타났고, 파충강과 양서 강에서는 원주형, 다각형 및 쐐기형이 나타났다. D세포는 모든 동물에서 원형, 난원형 및 방추형이 관찰되었고, 특히 파충강에서는 원추형및 쐐기형도 나타났다. PP세포는 주로 방추형 및 반원형이 대다수이였으며 간혹 원형 또는 다각형 등의 모습도 나타났다. 각 내분비세포의 출현율은 파충강 열 어강 들에서는 B, A, D 및 PP세포 순이었으나, 양서 강에서는 B, A, PP 및 D세포 순으로 나타났다. B와 PP세포는 양서강, 어강 및 파충강 순서로 출현하였고, A세포는 파충강, 어강 및 양서강의 순서이었으며 D세포는 어강, 파충강 및 양서강의 순서였다. 췌도 내에서의 세포의 분포 위치는 세포의 종류에 따라 차이를 보여 B세포의 경우 대다수 동물들에서 중앙부에 균등하게 분포하였으나 A, D및 PP세포는 주로 췌도 주변부에 분포하였고, 어강에서의 D세포는 췌도 중앙부에서도 관찰되었다. 일반적으로 파충강 및 양서 강에서는 외분비 선포조직에서초 내분비세포들이 출현하였으나, 어강에서는 내분비세포가 전혀 출현하지 않았다. 양서강 및 어강 들의 일부 수에서는 췌관상피에서도 드물게 나타났다.

• The Journal of the Acoustical Society of Korea
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• v.28 no.6
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• pp.557-565
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• 2009

To perceive the direction and the distance of a sound, we always use a couple of information. Head Related Transfer Function (HRTF) contains the information that sound arrives from a sound source to the ears of the listener, like differences of level, phase and frequency spectrum. For a reproduction system using 2 channels, we apply HRTF to many algorithms which make 3d sound. But it causes a problem to localize a sound source around a certain places which is called the cone-of-confusion. In this paper, we proposed the new algorithm to reduce the confusion of sound image localization. The difference of frequency spectrum and psychoacoustics theory are used to boost the spectral cue among each directions. To confirm the performance of the algorithm, informal listening tests are carried out. As a result, we can make the improved 3d sound in 2 channel system based on a headphone. Also sound quality of improved 3d sound is much better than conventional methods.

• Journal of Dental Rehabilitation and Applied Science
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• v.30 no.3
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• pp.206-214
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• 2014

This study is to evaluate how different bearing surface angles of abutment screw affect the mechanical stability of the joint in the conical seal design implant system. Materials and Methods: Internal connection type regular implants, two-piece cemented type abutments and tungsten carbide/carbon-coated titanium alloy abutment screws were selected. Titanium alloy screws with conical ($45^{\circ}$) and flat ($90^{\circ}$) head designs which fit on to abutment were fabricated. The abutments were tightened to implants with 30 Ncm by digital torque gauge. The loading was applied once to the central axis of abutment. The mean axial displacement was measured using micrometer before and after the tightening and loading (n = 5). The abutment was tightened to implants with 30 Ncm and T-shape stainless steel crown was cemented. Then the change in the amount of reverse-torque was measured after the repeated loading to the central axis, and the place 5 mm away from the central axis. Compressive bending and fatigue strength were measured at the place 5 mm away from the central axis (n = 5). Results: Both groups showed the largest axial displacement when abutment screw tightening and total displacement was greater in the flat head group compared to conical head group (P < 0.05). However, there were no significant differences in reverse torque value, compressive bending and fatigue strength (P > 0.05). Conclusion: Within the limitations of this study, the abutment screw head design had no effect on two groups regarding the joint stability, however the conical head design affected the settlement of abutment resulting in the reduced total displacement.

• Korean Journal of Plant Resources
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• v.29 no.4
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• pp.376-384
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• 2016

A comparative petal micromorphology of 15 taxa of tribe Sorbarieae was carried out using scanning electron microscopy (SEM) in order to evaluate their taxonomic and systematic implication. The characteristics of both adaxial and abaxial side of petal epidermal cells such as shape, arrangement, anticlinal wall and cuticular sculpture were described in detail. The Sorbarieae petal epidermal cells were identified as papillate or conical papillate (PCS) and rectangular-rugose tabular (TRS). Three types of petal micromorphology were found within the tribe based on the cell patterns of adaxial and abaxial side. Type I. PCS-TRS, Type II. PCS-PCS, Type III. TRS-TRS (adaxial-abaxial side). The petal epidermal cell types, anticlinal cell wall, and cuticular sculpture represent not only taxonomical importance for identification between or within the genera but also systematic implication. Moreover, this study provides a relation between petal epidermal cell pattern and insect pollinator (entomophily; melittophily) as an additional case.

• Journal of the Korean Academy of Esthetic Dentistry
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• v.24 no.2
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• pp.86-100
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• 2015

To harmonize with the remaining natural teeth a dentist and technician make an effort to do. Dental ceramic perfectly reproduce the functionality and esthetic is so moved that will deliver to the patient. However It is not easy to overcome the problem. Actually, it can't have the same spectrum curve between different object. The spectrum curve and reflectance is a unique feature of an object like fingerprints. So it is not that the identification of spectral curves that we usually focuses color. We need to understand the process of matamerism makes something like a combination of color perception. In other word that will tell in our field with ceramic teeth of the patient wish to match the color matching process to simulate the cone in our retinas with the same combination.

• Journal of Oral Medicine and Pain
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• v.31 no.2
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• pp.121-126
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• 2006

Hypohidrotic ectodermal dysplasia refers to a group of disorders with the following common features : thin, sparse or absent hair, missing or peg-shaped teeth and inability to sweat adequately. Both the primary and secondary dentition are affected. Teeth may be absent (anodontia) or reduced in number (oligodontia) and abnormally shaped. In case, A 5-year-old man presented with hypohidrosis and dry skin. He had no teeth in mouth. We report a case of hypohidrotic ectodermal dysplasia with anodontia.

• Geotechnical Engineering
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• v.14 no.5
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• pp.143-162
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• 1998

In the present study, a procedure to predict the depth from the ground surface to the center of bulging failure zone in each of the square granular group piles under a rigid mat foundation is proposed. This analytical procedure is established on the basis of the conical modeling of bulging failure shape and the replacement ratio of soft foundation soils. considering the effect of a share of procedure to estimate the ultimate cylindrical pressure in the area reinforced with granular piles and the ultimate bearing capacity of each of granular piles in group. This analytical procedure is also established on the basis of the pre-determined depth to the zone of bulging failure and an iterative solution technique. Finally the analytical procedures proposed in this study are verified by analyzing the results of 3D finite element analyses, and the predictions of ultimate bearing capacity of granular piles are compared with the results obtained from the tests, empirical equation and 3D finite element analyses.

• The Korean Journal of Zoology
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• v.39 no.4
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• pp.419-425
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• 1996

The five spedes of genus Iksookimia from Korea were investigated by electron microscopes to clarify the adhesive membranes on zona radiata. In the late vitellogenic stage the adhesive membranes could be classified into three form as follows: 1) villous form of Iksookimia koreensis, I pumila, and I. hugowolfeldi, 2) cotton-shaped form of I. longicorpus, and 3) vine-shaped form of I. choii. And although I. koreensis, I pumila, and I. hugowolfeldi possessed the same villous form, It was evident that fine structure of the zona radiata varied according to spedes. The adhesive membranes and fine structures of zona radiata in Iksookimla showed a species specificity related to closely their habitats and spawning properties.

• KOMUNHWA
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• no.61
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• pp.3-44
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• 2003

The plane structure of dwelling in korean peninsula has been transformed orderly as for shapes of round, square and rectangular in general. The exit and entrance structure take styles of stairs and when they are jotted out, take the slant stairs from the