• Proceedings of the KIPE Conference
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• 2001.10a
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• pp.232-235
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• 2001

This paper presents a circuit of the quasi-resonant DC link to achieve soft-switching three phase inverter using intelligent IGBT power module. The soft-switching operation in this circuit is confirmed simulation and experimental results. Its conductive noise is measured for electrical AC motor drive as compared with that of the conventional hard switching inverter.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.26 no.4
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• pp.380-386
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• 1990

The high stress, low cycle fatigue test were carried out on HT80 plates with artificial part-through notch. The LBB conditions by the net section stress approach was examined in detail. Finite element methods for the state of deformation were also applied and the results were compared with the results from experiments. From the test results, it was noted that the LBB condition in fatigue test was dependent upon the maximun load change before and after the crack penetration. The LBB criterion By the net section stress approach were slightly dependent on initial crack size. It was shown that the state of deformation can be used to predict whether the component is likely to show LBB condition or they will be broken rapidly.

• Journal of Chest Surgery
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• v.17 no.2
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• pp.197-204
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• 1984

The criss-cross, a term first used by Anderson and Ando , is a rare cardiac malformation in which the systemic and pulmonary blood streams cross at the atrioventricular level, without mixing. We have surgically experienced four cases of crossed atrioventricular connection, three concordant and one discordant, at Seoul National University Hospital from July 1982 to March 1984. The atrial situs, the atrioventriculoarterial connection, the spatial position of the ventricles, and associated cardiac anomalies were analyzed. We have performed right Blalock-Taussig shunt for case 1, modified Fontan operation for case 2, patch closure of VSD for case 3, and septation of common ventricle with primary closure of ASD for case 4. The relatively good postoperative results in these patients were gratifying and suggest that cardiac anomalies associated with this rare malformation can be successfully repaired without further risk. To our knowledge, this is the first report of surgical experience for criss-cross heart in the Korean literature.

• Journal of Information Display
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• v.12 no.3
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• pp.159-165
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• 2011

This research entailed the production of stereoscopic 3D (S3D) contents using 2D-to-S3D conversion for exhibition at a museum and subjective evaluation. Hybrid production combining S3D images of existing live-action videos using the 2D-to-S3D conversion technology and computer graphic ones created via stereo rendering was conducted. Design and control of the chronological analysis of the parallactic angle was conducted on the produced contents, using binocular information as well as subjective evaluations, with the intent of conducting an investigation on the characteristics of such contents from the perspectives of the producers and viewers. An investigation was also conducted on the effects of the viewing position on the impressions of the S3D images.

• Proceedings of the Korean Institute of Interior Design Conference
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• 2006.11a
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• pp.39-43
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• 2006

In recent years, local governments are interested in constructing museums of various scales in relationship to unique factors of each region regarding their positive effects on tourist industry. However, many museums have failed to reflect regional characteristics resulting uniformed, uninteresting museum architectures. This study analyzes museum architectures designed by Ando Dadao, Antoine Predock's, Charles Correa, Carlo Scarpa, and Ricardo Legorrata based on 7 criterias of Kenneth Prampton's critical regionalism theory which are natural environment, materials, light, weather, unique culture, and history. It Is hoped that this study may serve as a stopping stone towards designing museums that reflect distinctive regional identities of Korea.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.230-230
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• 2006

Density functional theory (DFT) calculations using the B3LYP hybrid functional and the 6-311++G(d,p) basis set have been performed to predict the wavelength dispersion of optical absorbance and refractive indices for organic compounds and polymers in the range between the vacuum UV (${\sim}157\;nm$) and near-IR (${\sim}850\;nm$). The DFT calculations can reproduce the experimental dispersions of absorbance and refractive indices with high accuracy and low costs. The calculated dispersions demonstrate that the judicious introductions of $-F\;and\;-CF_{3}$ into alicyclic and heterocyclic compounds are effective in reducing the absorption at shorter wavelengths. In addition, the calculated Abbe numbers that represent the refractive index dispersion in the visble region are linearly proportional to the calculated refractive indices at 589 nm.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.305-305
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• 2006

The molecular structure and dynamics of inclusion compounds (ICs) consisting of n-perfluoroalkane (PFA) guests and ${\Box}-cyclodextrin$ (${\Box}-CD$) host were investigated using $^{19}F$ magic angle spinning (MAS) and $^{1}H{\to}^{19}F$ cross polarization (CP) / MAS NMR spectroscopy with the aid of thermal analyses, FT-IR spectroscopy, X-ray diffraction, and $^{1}H{\to}^{19}F$ CP/MAS technique revealed that $C_{9}F_{20}$ molecules included in ${\Box}-CD$ undergo vigorous molecular motion and partly come out of the ${\Box}-CD$ channel above $80^{\circ}C$. In case of $C_{20}F_{42}/{\Box}-CD$, an exothermic peak is observed by differential scanning calorimetry (DSC) at ca. $40^{\circ}C$ which suggests that ${\Box}-CD$ molecules become mobile and commence rearrangements that form more ordered structures at higher temperatures.

• Kyungpook Mathematical Journal
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• v.49 no.1
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• pp.167-181
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• 2009

Based on Ricatti equation $XA^{-1}X=B$ for two (positive invertible) operators A and B which has the geometric mean $A{\sharp}B$ as its solution, we consider a cubic equation $X(A{\sharp}B)^{-1}X(A{\sharp}B)^{-1}X=C$ for A, B and C. The solution X = $(A{\sharp}B){\sharp}_{\frac{1}{3}}C$ is a candidate of the geometric mean of the three operators. However, this solution is not invariant under permutation unlike the geometric mean of two operators. To supply the lack of the property, we adopt a limiting process due to Ando-Li-Mathias. We define reasonable geometric means of k operators for all integers $k{\geq}2$ by induction. For three positive operators, in particular, we define the weighted geometric mean as an extension of that of two operators.

• Proceedings of the IEEK Conference
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• 2003.07b
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• pp.1007-1010
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• 2003

This paper presents in-circuit system-on-chip verification and debugging environment. To maximize the emulation speed, the software part is compiled natively for the host computer and the hardware part is mapped into FPGA. The two parts communicate with each other in transaction level. The operation of the hardware part and the software part is recorded independently during the emulation, and after the emulation is over, they are merged in a waveform to give user a unified view that covers both hardware and software.

• Proceedings of the IEEK Conference
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• 2003.07b
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• pp.859-862
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• 2003

This paper proposes an emulation environment for SoC designs using small number of large gate-count FPGA's and a PC system. To overcome the pin limitation problem in partitioning the design when the design size overwhelms the FPGA gate count, we use bus splitter modules that replicate on-chip bus signals in one FPGA to arbitrary number of other FPGA's with minimal pin count. The proposed scheme is applied to the emulation of 2 million gate multimedia processing chip using two Xilinx Viretex-2 6000 FPGA devices in 6.6MHz operating frequency. An ARM core, memories, camera and LCD display are modeled in software using dual 2GHz Pentium-III processors. This scheme can be utilized for more than 2 FPGA's in the same ways as two FPGA case without losing emulation speed.