• Journal of the Microelectronics and Packaging Society
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• v.23 no.4
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• pp.87-92
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• 2016

The importance of heat dissipation for the electric device modules along the thickness direction is increasing. Two types of two-layered materials, metal-metal bonding and dielectric-metal bonding, have been fabricated by roll bonding process and a thermal diffusivity of the specimens was measured along the thickness direction. The thermal diffusivity of specimens with metal-metal bonding measured by light flash analysis (LFA) showed a same value independent on the direction of heat flow. However, the thermal diffusivity of specimens with dielectric-metal bonding showed a big difference of 17.5% when the direction of heat flow changed oppositely in the LFA process. The measured thermal diffusivity of specimens when the heat flows from metal to dielectric direction showed smaller value of 17.5% compared to the value when the heat flow from dielectric to metal direction. The difference in thermal diffusivity of specimens with dielectric-metal bonding dependence on direction of heat flow is due to the electron-phonon resistance that occurred transfer process of electron energy to phonon energy near the interface.

• Journal of the Korean Chemical Society
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• v.57 no.4
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• pp.432-438
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• 2013

We report a contact angle goniometer that can be easily assembled and used in high school and general chemistry experiments. It consists of an LED flash, a sample stand, and a camera fixed on an optical bread board, and the sample area is covered to block light from outside with a box with holes on both sides. ImageJ, free image analyzing software and a JAVA plugin (Drop_analysis) were used to determine the contact angle of liquid drop resting on solid surface. The contact angles of various liquids were successfully measured on various surfaces. The solid surface energies have also been determined using the Owen-Wendt method from the contact angles of $H_2O$ and $CH_2I_2$. The results reasonably agree with the previously reported values, showing the surface characteristics and modification as well as the dispersive and polar contributions. These contact angle goniometer and method for determination of the contact angle and surface energy can be applied to observation of various surface properties including wettability, hydrophilicity, and water repelling. Students can learn how the surface properties are related to the intermolecular interactions and gain experience about the equilibrium between the related forces, optics, and mathematical derivations.

• Korean journal of applied entomology
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• v.13 no.4 s.21
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• pp.217-225
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• 1974

The damage by fruit-piercing moths in orchards, primarily on grapes cultivated on reclaimed hillsides in Koksung, Cholla Namdo, was surveyed during July to October, 1974. Moths collected at night, mostly with the aid of flash light, were then classified. Results are summairzed as follows; 1. In addition to the 14 species of fruit-piercing moths reported in Korea, 11 new species were collected lot the first time ia Korea. These include. Speiredonia retorta Clerck, Cocytodes coerulea Guenee, Metopta rectifasciata Menetries, Ophideres fullonica Linnaeus, Serrodes campana Guenee, Mythimna turca Linnaeus, Amphipyra livida Schiffermuller et Denis, Paralleia maturata Walker, Ophiusa tirhaca Cramer, Anomis mesogona Walker and Thyas dotata Fabricius. 2. The maximum emergence of moths in Koksung Orchard was from the 10th to the end of September. Only a few moths were observed befroe the begining of August or after October 10. 3. The number of moths flying to grape vines increased as the time advanced from sunset to midnight. Populations gradually decreased thereafter until 5:30 a. m., when only occasional moths were observed. 4. Average damage to grape fruits by these insects was virtually nil until August 10; with subsequent infestation rates of $1.0\%$ on August 15, $17.6\%$ on September 26, and $20.3%$ on October 4, respectively. 5. Fruits of less than 10 percent sugar content and higher than 6.2 acid value were free from damage by these moths, and those of higher sugar content and lower acid value to be more heavily attacked.

• The KIPS Transactions:PartD
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• v.11D no.2
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• pp.443-452
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• 2004

The paper presents an intelligent space management system for ubiquitous computing. The system is basically a home/office automation system that could control light, electronic key, and home appliances such as TV and audio. On top of these basic capabilities, there are four elegant features in the system. First, we can access the system using either a cellular Phone or using a browser on the PC connected to the Internet, so that we control the system at any time and any place. Second, to provide more human-oriented interface, we integrate voice recognition functionalities into the system. Third, the system supports not only reactive services but also proactive services, based on the regularities of user behavior. Finally, by exploiting embedded technologies, the system could be run on the hardware that has less-processing power and storage. We have implemented the system on the embedded board consisting of StrongARM CPU with 205MHz, 32MB SDRAM, 16MB NOR-type flash memory, and Relay box. Under these hardware platforms, software components such as embedded Linux, HTK voice recognition tools, GoAhead Web Server, and GPIO driver are cooperated to support user-friendly intelligent space.