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Yong‐Sung Eom Keon‐Soo Jang Ji‐Hye Son Hyun‐Cheol Bae Kwang‐Seong Choi 《ETRI Journal》2019,41(6):820-828
A highly reliable conductive adhesive obtained by transient liquid‐phase sintering (TLPS) technologies is studied for use in high‐power device packaging. TLPS involves the low‐temperature reaction of a low‐melting metal or alloy with a high‐melting metal or alloy to form a reacted metal matrix. For a TLPS material (consisting of Ag‐coated Cu, a Sn96.5‐Ag3.0‐Cu0.5 solder, and a volatile fluxing resin) used herein, the melting temperature of the metal matrix exceeds the bonding temperature. After bonding of the TLPS material, a unique melting peak of TLPS is observed at 356 °C, consistent with the transient behavior of Ag3Sn + Cu6Sn5 → liquid + Cu3Sn reported by the National Institute of Standards and Technology. The TLPS material shows superior thermal conductivity as compared with other commercially available Ag pastes under the same specimen preparation conditions. In conclusion, the TLPS material can be a promising candidate for a highly reliable conductive adhesive in power device packaging because remelting of the SAC305 solder, which is widely used in conventional power modules, is not observed. 相似文献
153.
Pak Chanil An Kwangil Jang Paeksan Kim Jonggun Kim Sok 《Multimedia Tools and Applications》2019,78(9):12027-12042
Multimedia Tools and Applications - This paper introduces new simple and effective improved one-dimension(1D) Logistic map and Sine map made by the output sequences of two same existing 1D chaotic... 相似文献
154.
Byunghun Hwang Young‐Min Jang Rammohan Mallipeddi Minho Lee 《International journal of imaging systems and technology》2013,23(2):114-126
The ultimate purpose of augmented cognition is to enhance human cognitive abilities, which are intrinsically limited. To enhance limited human cognitive abilities, we developed a human augmented cognition system that can offer appropriate information or services by actively responding to the user's intention. This article mainly describes a framework for probing human implicit intentions for the purpose of augmented cognition. The type of user intention, either task‐free human implicit intention or task‐oriented human implicit intention, can be predicted based on fixation count, fixation length, and pupil size variation induced by eye response. Further, these features are used to detect the transition point between task‐free human implicit intention and task‐oriented human implicit intention. Maximum a Posteriori in Naïve Bayes classification model is used for selecting relevant query keywords to search and retrieve specific information from a personalized knowledge database. The experimental results show that the proposed human intention recognition and probing models are suitable for achieving the goal of augmented cognition. © 2013 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 23, 114–126, 2013 相似文献
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Scientometrics - This study describes the increase of research productivity of latecomer countries (latecomers) in the high-energy physics (HEP) community by research strategies based on a national... 相似文献
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Junho Lee Myung-Gyu Seo Jong-Dae Hong Tae Soon Kim Changheui Jang 《Journal of Mechanical Science and Technology》2016,30(11):4931-4936
The effect of hot bending on the Low cycle fatigue (LCF) behavior of 347 SS was evaluated in Room temperature (RT) air and simulated Pressurized water reactor (PWR) water environments. The LCF life of 347 SS in PWR water was shorter than that in RT air for the as-received and hot-bent conditions. The LCF life of hot-bent 347 SS was relatively longer than that of the as-received condition in both RT air and PWR water. Microstructure analysis indicated development of dislocation structure near niobium carbide particles and increase in dislocation density for the hot-bent 347 SS. Such microstructure acted as barriers to dislocation movement during the LCF test, resulting in minimal hardening for the hot-bent 347 SS in RT air. 相似文献
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Hyun Kyu Jung Chang Hee Kim A-Ra Hong Seung Han Lee Tae Cheol Kim Ho Seong Jang Dong Hun Kim 《Ceramics International》2019,45(8):9846-9851
Functional materials exhibiting magnetic and luminescent properties have been recognized as an emerging class of materials with great potential in advanced applications. Herein, properties of multifunctional ceramic composites consisting of two garnets, luminescent cerium-doped Y3Al5O12 (Ce:YAG) and magnetic Y3Fe5O12 (YIG), are reported. On increasing the sintering temperature, both the photoluminescence and saturation magnetization of the Ce:YAG-YIG composites decreased gradually because of the interdiffusion of trivalent ions such as Al3+ and Fe3+. At a constant sintering temperature of 1100?°C, the YIG contents in the composites increased, thereby causing their luminescent properties to degrade and the saturation magnetizations to increase. For application to electronics, Ce:YAG-YIG composite thin films were integrated on quartz substrates by sputtering the ceramic target. The composite thin films exhibited both magnetic and luminescent properties after annealing. These techniques facilitate the incorporation of multifunctional nanocomposites into various devices. 相似文献