• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1998.04a
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• pp.561-567
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• 1998

Recently, TV makers have tried for high sound quality and power, However, due to the high power of the speaker the structure of set brings about a sound vibration problem. Therefore, this paper illustrates the sound vibration phenomenon for a monotype TV set and suggests guide lines for reducing the sound vibration in the design of TV sets,

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.201.2-201.2
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• 2003

A novel lanostane-type triterpene, (24E)-3,4-seco-9${\beta}$H-lanosta- 4(28),7,24- triene- 3,26- dioic acid was isolated from Abies koreana (Pinaceae) which is a tall evergreen tree grown indigenously in southern Korea. The structure of this compound was characterized by spectroscopic methods. Cytotoxicity of the compound was evaluated in vitro using the SRB method, and it showed marginal activity against human cancer cell lines.

• Archives of Pharmacal Research
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• v.22 no.3
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• pp.306-308
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• 1999

The oxidative dimerization of ferulic acid has been carried out using horse-radish peroxidase as catalyst to give a dihydrobenzofuran neolignan (1), the structure of which was elucidated as (2SR, 3RS)-2,3-dihydro-2-(4-hydroxy-3-methoxyphenyl)-3n-butoxycarbonyl-5-(2E-carboxyethenyl)-7methoxybenzofuran by spectroscopic analyses. This compound showed more potent cytotoxicity against several tumor cell lines than the starting material.

• Journal of Industrial Technology
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• v.27 no.B
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• pp.145-151
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• 2007

In this paper, a BPF with a dual mode folded ring resonator is presented. The dual mode ring resonator is also exactly analyzed by using Y-parameter method, in which the difference in admittance of two lines make the ring resonator work as a dual mode resonator. The proposed BPF has an advantage of small size compared to conventional one with dual mode ring resonator.

• Structural Engineering and Mechanics
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• v.8 no.3
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• pp.233-242
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• 1999

In the present study, the elasto-plastic analysis of prismatic plate structures subjected to pure bending is carried out using the finite strip method. The end cross-sections of the structure are assumed to remain plane during deformation, and the compatibility along corner lines is ensured by choosing proper displacement functions. The effects of both the initial geometrical imperfections and residual stresses due to fabrication are included in the combined geometrically and materially nonlinear simulation. The von-Mises yield criterion and the Prandtl-Reuss flow theory of plasticity are applied in modelling the elasto-plastic behavior of material. Newton-Raphson iterations are carried out as the rotation of the end cross sections of the structure is increased step by step. The parameter representing the overall axial strain of structure is adjusted constantly during the iteration process in order to eliminate the resulting overall axial force on any cross-section of the structure in correspondence with the assumption of zero axial force in pure bending. Several numerical examples are presented to validate the present method and to investigate the effects of some material and geometrical parameters.

• YAKHAK HOEJI
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• v.43 no.5
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• pp.559-565
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• 1999

The two gericudranin E derivatives, GER-I & II, were synthesized and evaluated their antitumour activities for the elucidation of structure-activity relationship. 2,4,6-Trihydroxyacetophenone was converted to target molecules GER-I and GER-B in 5 steps via sequential protection, aldol condensation, Michael type-cyclization, regioselective C-benzylation. The cellular growth inhibition of compounds GER-I and GER-II were investigated against P388, L1210, K562, HCT-15, SK-HepG-1, MCF-7 as cancer cell lines and mouse splenocytes as a normal cell by MTT assay.

• Journal of the Korean Applied Science and Technology
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• v.25 no.3
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• pp.380-387
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• 2008

The effects of the applied stretch and MgADP binding on the structure of the actin and myosin cross-bridges in rabbit fibers in the rigor state have been investigatedwith improved resolution by x-ray diffraction using synchrotron radiation. To clarify the structure of the ATP hydrolysis intermediates formed by actin and myosin cross-bridges,the effects of various phosphate analogs in the of MgADP on the structure of the thin and thick filaments in glycerinated rabbit muscle fibers in the rigor state investigated by x-ray diffraction with a short exposure time using synchrotron radiation. These results strongly suggest that when MgADP and phosphate analogs such as metallofluorides(BeF3 and AlF4)and vanadate(VO4(Vi)) were added the rigor fibers in the presence of the ATP-depletion backup system, the intensities of the actin-based layer lines were markedly weakened. We found that the intensity of the 14.5 nm-based meridional reflections increase by 20-50% when phosphate analogs such as metallofluorides(BeF3 and AlF4) and vanadate(VO4(Vi)) was added to the rigor muscle.

• Progress in Superconductivity
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• v.4 no.1
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• pp.74-79
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• 2002

High-speed probe made to test single flux quantum(SFQ) circuits was comprised of semi-rigid coaxial cables and microstrip lines. The impedance was set at 50 $\Omega$to carry high-speed signals without much loss. To do performance test of high-speed probe, we have attempted to fabricate a test chip which has a coplanar waveguide(CPW) structure. Electromagnetic simulation was done to optimize the dimension of CPW so that the CPW structure has an impedance of 50$\Omega$, matching in impedance with the probe. We also used the simulation to investigate the effect of the width of signal line and the gap between signal line and ground plane to the characteristics of CPW structure. We fabricated the CPW structure with a gold film deposited on Si wafer whose resistivity was above $1.5\times$10$_4$$\Omega$.cm. The magnitudes of S／sub 21／ of CPW at 6 ㎓ in simulations and in the actual measurements done with a network analyzer were: -0.1 ㏈ and -0.33 ㏈ (type A),-0.2 ㏈ and -0.48 ㏈ (type B), respectively. Using the test chip, we have successfully tested the performance of high-speed probe made for SFQ circuits. The probe showed the good performance overthe bandwidth of 10 ㎓.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.11
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• pp.1662-1667
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• 2012

This paper describes the design of size-reduced ring hybrid couplers (RHC) using a common defected ground structure (CDGS). The proposed RHC consists of double-sided microstrip line and the CDGS patterns which are placed in the common ground plane of the double-sided microstrip line. The effects of DGS as a periodic structure are imposed on both microstrip lines, so the advantages of the existing DGS are doubled. The normal RHC is designed first and folded by the half reference plane with the CDGS realized on the common ground plane. So another trial for size-reduction is performed by folding the RHC and inserting CDGS besides to the conventional DGS. In order to show a design example, a 2GHz RHC is designed and miniaturized using CDGS. The size of the miniaturized RHS is around 50% of the normal one, while the performances are well preserved even after the size-reduction.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08b
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• pp.1168-1171
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• 2007

Integrating systems on TFT-LCD panels is more and more popular for the mobile display application. However, it may not be necessary to use LTPS TFT devices. A-Si TFTs are used to integrate systems on TFT-LCD panels, especially scan (gate) drivers. To further reduce the chip size of driver IC, the triplegate pixel structure is developed. Therefore, the number of the source lines is reduced to 1/3 times.