• Journal of Pharmaceutical Investigation
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• v.41 no.5
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• pp.295-300
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• 2011

Paclitaxel is a well known anticancer agent and has been a pharmaceutical challenge because of its extremely poor water-solubility and susceptibility to the p-glycoprotein (p-gp)-mediated efflux in multi-drug resistant (MDR) cancer cells. Tributyrin (TB), a triglyceride with relatively short fatty acid chains, was chosen as solubilizing vehicle for paclitaxel based on the solubility study (26.6 mg/mL). Tributyrin (10%) o/w emulsion containing paclitaxel (5%), egg phosphatidylcholine (5%) and pegylated phospholipid (0.5%) was prepared by high pressure homogenization to obtain submicron-sized emulsion. The mean particle size of the resultant TB emulsion was 395.5 nm. Paclitaxel in TB emulsion showed higher anticancer activity against human breast cancer cell line, MCF-7, than free form delivered in DMSO solution. On the other hand, its anticancer activity was significantly reduced in MCF-7/ADR, a MDR variant cancer cell line of MCF-7, and recovered by the presence of verapamil, suggesting of the susceptibility to the p-gp mediated efflux even though paclitaxel was encapsulated into emulsion. The TB emulsion showed great potential as a promising vehicle for water-insoluble anticancer agent, paclitaxel.

• Journal of information and communication convergence engineering
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• v.6 no.2
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• pp.122-128
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• 2008

Multiprocessor architectures and platforms, such as, a multiprocessor system on chip (MPSoC) recently introduced to extend the applicability of the Moore's law, depend upon concurrency and synchronization in both software and hardware to enhance design productivity and system performance. With the rapidly approaching billion transistors era, some of the main problem in deep sub-micron technologies characterized by gate lengths in the range of 60-90 nm will arise from non scalable wire delays, errors in signal integrity and non-synchronized communication. These problems may be addressed by the use of Network on Chip (NOC) architecture for future System-on-Chip (SoC). We have modeled a concurrent architecture for a customizable and scalable NOC in a system level modeling environment using MLDesigner (from MLD Inc.). Varying network loads under various traffic scenarios were applied to obtain realistic performance metrics. We provide the simulation results for latency as a function of the buffer size. We have abstracted the area results for NOC components from its FPGA implementation. Modeled NOC architecture supports three different levels of quality-of-service (QoS).

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.05b
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• pp.30-33
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• 2001

Chemical mechanical polishing(CMP) process has been widely used to planarize dielectrics, which can apply to employed in integrated circuits for sub-micron technology. Despite the increased use of CMP process, it is difficult to accomplish the global planarization of free-defects in inter-level dielectrics (ILD). Especially, defects like micro-scratch lead to severe circuit failure, and affects yield. CMP slurries can contain particles exceeding $1{\mu}m$ size, which could cause micro-scratch on the wafer surface. The large particles in these slurries may be caused by particle agglomeration in slurry supply line. To reduce these defects, slurry filtration method has been recommended in oxide CMP. In this work, we have studied the effects of filtration and the defect trend as a function of polished wafer count using various filters in inter-metal dielectric(IMD)-CMP. The filter installation in CMP polisher could reduce defect after IMD-CMP. As a result of micro-scratches formation, it shows that slurry filter plays an important role in determining consumable pad lifetime.

• Proceedings of the KSRS Conference
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• v.1
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• pp.316-319
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• 2006

Monthly-mean aerosol parameters derived from the 1998-2004 SeaWiFS observations over East Asian waters are analyzed. SeaWiFS GAC Level 1 data covering the Northeast Asian area are collected and processed by the standard atmospheric correction algorithm released by the SeaWiFS Project to produce daily aerosol optical thickness (AOT) and ${{\AA}}ngstr{\ddot{o}}m$ exponent imageries. Monthly mean AOT and ${{\AA}}ngstr{\ddot{o}}m$ exponent values are extracted from the daily composite images for six study areas chosen from the surrounding waters of Japan. A slight increasing trend of ${{\AA}}ngstr{\ddot{o}}m$ exponent is found and interpreted as about 4-5% increase in submicron fraction of aerosol optical thickness at 550nm. Two cloud screening methods, including the standard cloud masking method of SeaWiFS and the one based on the local variance method, are applied to the SeaWiFS data processing, in an attempt to inspect the influence to the observed statistical uptrend which probably induced by different cloud mask algorithms. The variability comes from the different cloud masking algorithms are discussed.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.11a
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• pp.707-710
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• 2004

Chemical mechanical polishing (CMP) process has been widely used to planarize dielectric layers, which can be applied to the integrated circuits for sub-micron technology. Despite the increased use of CMP process, it is difficult to accomplish the global planarization of in the defect-free inter-level dielectrics (ILD). In this paper, we have investigated slurry properties and CMP performance of silicon dioxide (oxide) as a function of different temperature of slurry. Thermal effects on the silica slurry properties such as pH, particle size, conductivity and zeta potential were studied. Moreover, the relationship between the removal rate (RR) with WIWNU and slurry properties caused by changes of temperature were investigated. Therefore, the understanding of these temperature effects provides a foundation to optimize an oxide CMP Process for ULSI multi-level interconnection technology.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.14 no.7
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• pp.557-561
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• 2001

Chemical mechanical polishing (CMP) process has been widely used to planarize dielectric layers, which can be applied to the integraded circuits for sub-micron technology. Despite the increased use of CMP process, it is difficult to accomplish the global planarization of in the defect-free inter-level dielectrics (ILD). Especially, defects such as micro-scratch lead to severe circuit failure which affect yield. CMP slurries can contain particles exceeding 1㎛ in size, which could cause micro-scratch on the wafer surface. The large particles in these slurries may be caused by particles agglomeration in slurry supply line. To reduce these defects, slurry filtration method has been recommended in oxide CMP. In this work, we have studied the effects of filtration and the defect trend as a function of polished wafer count using various filters in inter-metal dielectrics(IMD)-CMP process. The filter installation in CMP polisher could reduce defects after IMD-CMP process. As a result of micro-scratch formation, it is shown that slurry filter plays an important role in determining consumable pad lifetime. The filter lifetime is dominated by the defects. We have concluded that slurry filter lifetime is fixed by the degree of generating defects.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07b
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• pp.735-738
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• 2003

Downsizing electronics requires precision position control with an accuracy of sub-micron order, which demands development of ultra-fine displacive devices. Piezoelectric transducer is one of devices transferring electric field energy into mechanical energy and being capable for fine displacement control. The transducer has been widely used as fine Position control device Multilayer piezoelectric actuator, one of typical piezo-transducer, is fabricated by stacking alternatively ceramic and electrode layers several hundred times followed by cofiring process. Electrode material should be tolerable in the firing process maintaining at ceramic-sintering temperatures up to $1100{\sim}1300^{\circ}C$. Ag-Pd can be used as stable electrode material in heat treatment above $960^{\circ}C$. Besides, adding small quantity ceramic powder allow the actuator to be fabricated in a good shape by diminishing shrinkage difference between ceramic and electrode layers, resulting in avoidance of crack and delamination at and/or nearby interface between ceramic an electrode layers. This study presents synthesis of nano-oxide-added Ag/Pd powders and its feasibility to candidate material tolerable at high temperature. The powders were formed in a co-precipitation process of Ag and Pd in nano-oxide-dispersed solution where Ag and Pd precursors are melted in $HNO_3$ acid.

• Journal of the Korean Ceramic Society
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• v.38 no.6
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• pp.551-557
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• 2001

La$_{0.7}$Ca$_{0.3}$MnO$_3$분말을 용액연소법으로 제조하였으며 분말 특성과 CMR에 응용하기 위해 박막의 전기적, 자기적 특성을 조사하였다. 조성과 구조 특성을 XRD와 SEM으로부터 조사하였으며 분말의 하소온도를 TG 분석으로부터 결정하였다. 또한 소결성은 dilatometer에 의해 조사되었으며 분말 특성은 BET에 의해 조사되었다. 소결성이 우수한 분말을 이용하여 스퍼터 타겟으로 제조하였으며 SiO$_2$/Si 기판 위에 스퍼터링한 후, 온도에 따른 four point probe 측정으로 막의 MR비를 측정하였다. VSM (Vibrating Sample Magnetometer)를 이용하여 증착된 막의 온도에 따른 자화율(Magnetization:M)을 측정하였다. 분말 특성으로는 평균입자 크기가 sub-micron 이하로 초미세하고 49.44$m^2$/g의 비표면적 값을 얻을 수 있었으며 고순도의 perovskite 구조를 갖는 La$_{0.7}$Ca$_{0.3}$MnO$_3$분말을 쉽게 얻을 수 있었다. 온도에 따른 저항값의 변화로부터 96K에서 최고의 MR값을 얻을 수 있었으며, 240K에서 강자성체로 전이되었다.로 전이되었다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.104-104
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• 2010

With the advent of nano-particle fillers in insulating materials, the insulating materials of superior quality have come to fore. In the recent past, nanocomposite LDPE/XLPE (Low Density Polyethylene/Cross Linked Polyethylene) power cable dielectrics have been synthesized. A preliminary evaluation of these new class of materials seem to show that, addition of small amounts of sub-micron inorganic fillers improved the dielectric properties of the composite, in particular, the volume resistivity, and the DC breakdown strength. The thermal behaviour, for example, the stability of composites against decomposition and ensuing electrical failure, do not seem to have been addressed. In a conventional XLPE insulated cable, the average thermal breakdown strength and maximum temperature at the onset of breakdown were seen to be markedly lower than the corresponding intrinsic breakdown strength and decomposition temperature. In this page, analysis of DC Breakdown of nano-composite insulating material for HVDC Cable is introduced.

• Proceedings of the IEEK Conference
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• 2008.06a
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• pp.525-526
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• 2008

This paper proposes a new high-speed level shifter using a special high voltage device with low threshold voltage. Also, novel low voltage swing method is proposed. The high voltage device is a standard LDMOS(Laterally Diffused MOS) device in a $0.18{\mu}m$ CMOS process without adding extra mask or process step to realize it. A level shifter uses 5V LDMOSs as voltage clamps to protect 1.8V NMOS switches from high voltage stress the gate oxide. Also, level-up transition from 1.8V to 5V takes only 1.5ns in time. These circuits do not consume static DC power, therefore they are very suitable for low-power and high-speed interfaces in the deep sub-quarter-micron CMOS technologies.