• Natural Product Sciences
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• v.20 no.4
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• pp.274-280
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• 2014

Six compounds were isolated from the n-BuOH fraction of the aerial parts of Aruncus dioicus var. kamtschaticus including: sambunigrin (1), prunasin (2), aruncide A (3), aruncide C (4), 1-O-caffeoyl-${\beta}$-D-glucopyranose (5), and caffeic acid (6). Their structures were confirmed by comparing the spectral data with those reported in the literature. The isolated compounds (1 - 6) were then examined for their cytotoxic effects towards MCF-7, HL-60, and HeLa cancer cell lines, as well as their DPPH radical scavenging activity. The results indicated that compound 4 possessed the strongest inhibitory effect toward HeLa cell line with $IC_{50}$ value of $5.38{\pm}0.92{\mu}M$. Compound 3 possessed selective cytotoxic activity on HL-60 cells with $IC_{50}$ value of $6.27{\pm}0.17{\mu}M$, compound 5 was found as the best in inhibiting proliferation with $IC_{50}$ value of $2.25{\pm}0.09{\mu}M$, and the other compounds showed significant inhibition with $IC_{50}$ values ranging from 6.10 to $11.27{\mu}M$. Compound 5 also displayed the strongest cytotoxic effect toward MCF-7 cell line ($IC_{50}$ $4.32{\pm}0.15{\mu}M$). Both 5 and 6 demonstrated strong radical scavenging activity ($IC_{50}$ $6.87{\pm}0.03$ and $4.33{\pm}0.22{\mu}M$, respectively). Compounds 1 and 5 were isolated for the first time from this plant.

• The Journal of Advanced Prosthodontics
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• v.5 no.1
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• pp.36-43
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• 2013

PURPOSE. The objective of this study was to compare the fracture toughness ($K_{Ic}$) obtained from the single edge V-notched beam (SEVNB) and the fractographic analysis (FTA) of a glass-infiltrated and a zirconia ceramic. MATERIALS AND METHODS. For each material, ten bar-shaped specimens were prepared for the SEVNB method ($3mm{\times}4mm{\times}25mm$) and the FTA method ($2mm{\times}4mm{\times}25mm$). The starter V-notch was prepared as the fracture initiating flaw for the SEVNB method. A Vickers indentation load of 49 N was used to create a controlled surface flaw on each FTA specimen. All specimens were loaded to fracture using a universal testing machine at a crosshead speed of 0.5-1 mm/min. The independent-samples t-test was used for the statistical analysis of the $K_{Ic}$ values at ${\alpha}$=0.05. RESULTS. The mean $K_{Ic}$ of zirconia ceramic obtained from SEVNB method ($5.4{\pm}1.6\;MPa{\cdot}m^{1/2}$) was comparable to that obtained from FTA method ($6.3{\pm}1.6\;MPa{\cdot}m^{1/2}$). The mean $K_{Ic}$ of glass-infiltrated ceramic obtained from SEVNB method ($4.1{\pm}0.6\;MPa{\cdot}m^{1/2}$) was significantly lower than that obtained from FTA method ($5.1{\pm}0.7\;MPa{\cdot}m^{1/2}$). CONCLUSION. The mean $K_{Ic}$ of the glass-infiltrated and zirconia ceramics obtained from the SEVNB method were lower than those obtained from FTA method even they were not significantly different for the zirconia material. The differences in the $K_{Ic}$ values could be a result of the differences in the characteristics of fracture initiating flaws of these two methods.

• Transactions on Electrical and Electronic Materials
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• v.14 no.6
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• pp.304-307
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• 2013

Reverse engineering of semiconductor devices utilizes delayering processes, in order to identify how the interconnection lines are stacked over transistor gates. Cu metal has been used in recent fabrication technologies, and de-processes becomes more difficult with the shrinking device dimensions. In this article, reverse engineering technologies to reveal the Cu interconnection lines and Cu via-plugs embedded in dielectric layers are investigated. Stacked dielectric layers are removed by $CF_4$ plasma etching, then the exposed planar Cu metal lines and via-plugs are selectively delineated by wet chemical solution, instead of the commonly used plasma-based dry etch. As a result, we have been successful in extracting the layouts of multiple layers within a system IC, and this technique can be applicable to other logic IC, analog IC, and CMOS IC, etc.

• Proceedings of the KIEE Conference
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• 1999.07f
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• pp.2786-2788
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• 1999

In this paper, a mixed mode exciting resonant inverter topology applicable to high performance electronic ballast is presented. Mixed mode exciting technique combines the attractive features of self exciting resonant inverter with those of external exciting one. The control IC is designed and manufactured by using a 0.8um CMOS process for 5V operation and has only 8 pins. This performs the operations of filament preheating, dimming control, output power regulation and protections. The mixed mode exciting resonant inverter with control IC has very simple structure, high performance and expensive manufacturing cost.

• Journal of Mechanical Science and Technology
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• v.18 no.3
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• pp.357-369
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• 2004

The purposes of the paper are to analyze the fracture phenomenon by delamination and cracking when the encapsulant of plastic IC package with polyimide coating shows viscoelastic behavior under hygrothermal loading in the IR soldering process and to suggest more reliable design conditions by the approaches of stress analysis and fracture mechanics. The model is the plastic SOJ package with the polyimide coating surrounding chip and dimpled diepad. On the package without cracks, the optimum position and thickness of polyimide coating to decrease the maximum differences of strains at the bonding surfaces of parts of the package are studied. For the model delaminated fully between the chip and the dimpled diepad, C(t)-integral values are calculated for the various design variables. Finally, the optimal values of design variables to depress the delamination and crack growth in the plastic IC package are obtained.

• Proceedings of the KIEE Conference
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• 2002.11c
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• pp.481-484
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• 2002

In recent, the contactless IC card is widely used in traffic, access control system and so forth. And its use becomes a general tendency more and more because of the development of RF technology and improvement of requirement for user convenience. This paper describes the hardware module to process contactless protocol for implementation contactless IC card. And the hardware module consists of specific digital logic circuits that analyze digital signal from analog circuit and then generate data & status signal for CPU, and that convert the data from CPU into digital signal for analog circuit.

• Proceedings of the KIEE Conference
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• 1998.07f
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• pp.2085-2087
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• 1998

This paper presents the design method of a dimming electronic ballast for fluorescent lamps using a frequency control IC, and investigates the effects of circuit variables on its dimming characteristics. It is shown that effective dimming is possible with IC IR2151 for frequency control, and this leads to a feasible design of more smaller and cheaper dimming ballast. Five ballasts different in the values of the series inductance and capactance are designed, and their dimming characteristics are compared. As the result, the dimming range becomes more broader as the series inductance gets smaller and the capacitance larger. Thus appropriate selection of the values of L and C should be made according to the types of application site.

• Proceedings of the KIEE Conference
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• 2001.07d
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• pp.2039-2041
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• 2001

According to the deregulation of governments in the world, the power industries of United State and European nations are proceeding remote meter reading and remote load control. But the core technology of multifunctional electronic meter implemented by programmable one-chip IC, which can be the right answer of ail the power industy's efforts is now still under development in the advanced countries. Implementation of smallest size, lowest price three-phase meter with features which enable distribution automation such as bidirectional communication. The three phase metering IC and meter can be used as metering, automatic meter reading and transformer monitoring. Prepayment billing system.

• Journal of Korean Neurosurgical Society
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• v.29 no.9
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• pp.1188-1194
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• 2000

Objective : Internal carotid-posterior communicating artery(IC-PC) aneurysms can be clipped easily without any special preparations. Occasionally, however, it is difficult to clip the low-lying IC-PC aneurysms without some kinds of additional procedures. Clinical Material and Methods : We experienced four cases of low-lying IC-PC aneurysms, which the intradural anterior clinoidectomy and/or anterior petroclinoid fold(APF) resection was essential to expose the proximal side of the aneurysmal neck and/or proximal control. One patient harbored two low-lying IC-PC aneurysms bilaterally. The patients were divided into two groups according to the necessity of anterior clinoidectomy : Group I(n=4) that needed an intradural clinoidectomy and/or APF resection and Group II(n=29) that had IC-PC aneurysms, easily clipped without any special preparation. Also, various radiometric parameters were measured through the preoperative angiograms. Results : The incidence of such aneurysms was 12% among a total of thirty-three surgically treated IC-PC aneurysms during lasr 3 years. Among four cases, three cases presented with subarachnoid hemorrhage and all aneurysmal sac projected to postero-inferior direction. In our study, We initially considered the necessity of intraoperative anterior clinoid process(ACP) removal and/or resection of APF in cases of shorter distance less than 5.6mm between the proximal aneurysmal sac and tip of the ACP(p<0.001), and the proximal portion of aneurysmal neck has located below the interclinoid line(p=0.001). Conclusion : Through a careful preoperative evaluation, some radiometric parameters can be used to determine whether the ACP should be removed in clipping of the low-lying IC-PC aneurysms. Unlike to total removal of the ACP, the intradural partial anterior clinolidectomy and/or APF resection, which are more familiar to surgeons, reduce the risks of the premature rupture, operative time, and also contribute a more precise clip placement with proximal control than the extradural clinoidectomy.

• Proceedings of the KIEE Conference
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• 2003.11c
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• pp.713-716
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• 2003

In recent, the contactless IC card is widely used in traffic, access control system and so forth. Contactless smart cards use a technology that enables card readers to provide power for transactions and communications without making physical contact with the cards. Usually electromagnetic signal is used for communication between the card and the reader. Contactless card is highly suitable for large quantity of card access and data transaction. And its use becomes a general tendency more and more because of the development of RF technology and improvement of requirement for user convenience. This paper describes the hardware module to process contactless protocol for implementation contactless IC card. And the hardware module consists of specific digital logic circuits that analyze digital signal from analog circuit and then generate data & status signal for CPU, and that convert the data from CPU into digital signal for analog circuit.