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In this study, an alumina coated silver core/shell structure particles were prepared through a solgel approach. Various techniques were used to characterize the as-prepared products, including field emission scanning electron microscopy (FE-SEM), field emission transition electron microscopy(FE-TEM), energy-dispersive X-ray spectroscopy (EDS) and thermal transient method. FE-SEM images showed a morphology of alumina coated Ag(ACA) particle and FE-TEM images showed a cross-section of synthesized alumina shell. EDS mapping confirmed that the synthesized shell was composed of Al and O. The thickness of the alumina shell satisfying high insulation resistivity and thermal conductivity was 23.5 nm. The electrical resistance and thermal conductivity of underfill using this alumina coated Ag (ACA) particle was 1.6E12 ?-cm and 1.9 Wm^-1 K^-1. When alumina coated Ag (ACA) particle and alumina were mixed to increase the thermal conductivity, it could be possible to achieve 2.34 Wm^-1 K^-1.

In this study, we investigated the correlation between thermal conductivity and insulative shell thickness of SiO2 coated Ag (SCA) particles for the thermal filler material in the high performance underfill with focus on improved thermal conductivity. We synthesized the coating of various SiO2 insulation layer on the surface of spherical Ag powder and used them for underfill material formulation to achieve >2 W/mK grade high thermal conductivity capillary underfill. In order to achieve powder distribution with gaussian curve additional spherical alumina was mixed with SCA powder. This mixture blended with epoxy based multifunctional resin matrix. Trend profiling of thermal conductivity and electrical resistivity as a function of SiO2 shell thickness were performed. In addition, correlation of thermal conductivity and viscosity were investigated. Resulting capillary underfill with SCA powders showed 2.14 W/mK thermal conductivity and passed thermal cycling test corresponding to JEDEC LEVEL 3.

We investigated the PANDA type polarisation-maintaining optical fibers which were drawn VAD synthesized preforms with stress-applying parts(SAP) by VAD method. The fabricated fiber has 1.3 mm beatlength in the 633 nm region, and −25 dB/km crosstalk. So ths fiber can be used in precision gyroscope system.

Recently, the use of bend-insensitive fiber in FTTH applications has become a major issue. The R&D center of OPTOMAGIC is in the process of verifying and presenting the possibility of using holey fiber in the telecommunications field through various reliability testing while comparing it to conventional single mode optical fiber.

The authors propose a two-stage recognition procedure using adjusted fuzzy membership functions. In the first stage, the recognition procedure inspects the rough feature in unknown patterns, and generates an alpha-cut set by the adjusted fuzzy membership function. If ambiguity is found in the first stage, the second stage procedure is invoked. Also weight values for calculating the distance are generated at each stage. An adjusted fuzzy membership function consists of a conventional fuzzy membership function and a fuzzy membership function changed by objective conditions. >