• Journal of Korean Ophthalmic Optics Society
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• v.4 no.2
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• pp.17-22
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• 1999

In this study, corneal power and eye refraction error were studied on myopic of unaccommodated koreans. The mean of refraction error power is -2.39D(male : -2.75D, female : -2.02D). The mean of corneal refraction error power is +43.90D(male : +44.07D, female : +43.71D). It is +0.90D higher than that of the model eye by Gullstrand(about + 43.00D).

• Journal of Korean Ophthalmic Optics Society
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• v.4 no.1
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• pp.27-35
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• 1999

The corneal power and eye refraction error were studed in 472 unaccommodated right eyes of Korean adult human aged above 20 years. The mean corneal refractive power is 44.08D (female : 44.28D, male : 43.76D). It is 1.1D higher than that of the medel eye by Gullstrand (about 43.0D). The mean corneal power of myopia(44.11D) is similar that of emmetropia(43.97D) and hyperopia(44.24D), but mean corneal power of myopia between the ages of 20 and 29 is 1.42D higher than that of emmetropia. The corneal powers as a function of ages are enlarged with increasing rate of 0.2D~0.3D/10years.

• IT SoC Magazine
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• s.12
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• pp.43-43
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• 2006

• Bulletin of the Korean Space Science Society
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• 2003.05b
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• pp.43-43
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• 2003

No Abstract, See Full Text

• Bulletin of the Korean Mathematical Society
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• v.43 no.4
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• pp.831-839
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• 2006

By relaxing the requirements for a sequence of functions to be a delta sequence, a space of Boehmians on the torus ${\beta}(T^d)$ is constructed and studied. The space ${\beta}(T^d)$ contains the space of distributions as well as the space of hyperfunctions on the torus. The Fourier transform is a continuous mapping from ${\beta}(T^d)$ onto a subspace of Schwartz distributions. The range of the Fourier transform is characterized. A necessary and sufficient condition for a sequence of Boehmians to converge is that the corresponding sequence of Fourier transforms converges in $D'({\mathbb{R}}^d)$.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.14 no.7
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• pp.692-698
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• 2003

This paper presents IM model which is produced in 3 port RF passive component. We calculated forward and reflect PIM of 3 port component by using the model. And they are reasonable agreement with measurement result like below. In the case of forward IM, calculated result is -122 dBc(at 43 dBm), which differ 2.5 dB with measurement result. And reflected IM, the average calculated result is -130 dBc(at 43 dBm), which differ 3 dB with measurement result. The results which are calculated and measured under various condition(IM source level, frequency sweep, contour length, etc.) show that forward method gets more fixed result than that of reflect. Consequently, PIM of 3 port component is predicted and analyzed for desensitizing by the proposed model.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.1
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• pp.49-56
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• 2000

The 2-O-$\alpha$-D-glucopyranosyl L-ascorbic acid (AA-2G) which was enzymatically glucosylated with the cyclodextrin glucanotransferase (CGTase) [EC 2.4.1.19] from Bacillus sp. JK-43 has been reported previously. The presnet experiments examined the optimal conditons for the productio of AA-2G from AA and soluble starch, and characterized the properties of the CGTase from Bacillus sp. JK-43. The reaction mixture for the maximal production of AA-2G was followings; 12% total substrate concentration, 1,400 usits/mL of CGTase and a mixing ratio of 2 : 3(g or AA : g of soluble starch). Under this condition, 1.76mM of AA-2G, which corresponded to 2.53% yield based on AA, was produced after incubation for 24hrs at 45$^{\circ}C$ (pH 5.5). The optimum pH and temperature for the CGTase activity were 6.0 and 45$^{\circ}C$, respectively. The enzyme was stable at pH 5.5 to 9.5, and at temperature up to 5$0^{\circ}C$. The thermostability of the enzyme could be enhanced up to 6$0^{\circ}C$ by the addition of 30mM CaCl2.

• Journal of IKEEE
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• v.23 no.2
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• pp.425-430
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• 2019

This work describes the design and characterization of a X-band power amplifier (PA) monolithic microwave integrated circuit (MMIC) using a $0.25{\mu}m$ gate length gallium nitride (GaN) high electron mobility transistor (HEMT) technology. The developed X-band power amplifier MMIC has small signal gain of over 22.7 dB and saturated output power of 43.02 dBm (20.04 W) over the entire band of 9 to 10 GHz. Maximum saturated output power is a 43.84 dBm (24.21 W) at 9.5 GHz. Its power added efficiency (PAE) is 41.0~51.24% and the chip dimensions are $3.7mm{\times}2.3mm$, generating the output power density of $2.84W/mm^2$. The developed GaN power amplifier MMIC is expected to be applied in a variety of X-band radar applications.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.43 no.3
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• pp.87-94
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• 2020

In this study, the factors affecting the efficiency of 48 projects of private R&D institutes were analyzed using the Tobit model. Influencing factors were selected as open R&D network size, IT industry, interaction between R&D network size and IT industry, and type of R&D network cooperation. As a result of Tobit analysis, the R&D network size, the IT industry, and the type of R&D network cooperation were found to be significant. The larger the open R&D network size, the lower the efficiency, and the IT industry showed lower R&D efficiency than other industries. In addition, cooperation with universities and research institutes showed lower R&D efficiency than cooperation with companies. As a result of these studies, companies will be able to select and focus on cooperation with the outside in relations and investment allocation.

• Korean Journal of Remote Sensing
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• v.23 no.1
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• pp.43-53
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• 2007

In this study, two standard specifications such as GML (Geography Markup Language) from OGC (Open Geo-spatial Consortium, Inc.) and X3D (extensible 3D) from Web3D consortium were dealt with for a web-based 3D urban application without using commercialized tools. In the first step of this study, DEM (Digital Elevation Model) and 3D GIS data sets were converted to GML structure with attribute schema. Then, these GML elements were projected onto a common coordinate system, and they were converted to the X3D format for visualization on web browser. In this work, a 3D urban data model, as a simple framework model, is extended to a framework model having further detailed information, depending upon application levels. Conclusively, this study is to demonstrate for practical uses of GML and X3D in 3D urban application and this approach can be applied to other application domains regarding system integrators and data sharing communities on distributed environments.