• Journal of Sensor Science and Technology
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• v.29 no.1
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• pp.45-50
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• 2020

Magnetoelectric (ME) composites were designed using the PMN-PZT single crystal and Ni foils; the properties and magnetic-field sensitivities of ME composites with different piezoelectric vibration modes (i.e., 31, 32, and 36 modes that depend on the crystal orientation of the single crystal) were compared. In the off-resonance condition, the ME coupling properties of the ME composites with the 32 and 36 piezoelectric vibration modes were better than those of the ME composites with the 31 piezoelectric vibration mode. However, in the resonance condition, the ME coupling properties of the ME composites were almost similar, irrespective of the piezoelectric vibration mode. Additionally, in the off-resonance condition (at 1 kHz), the magnetic-field sensitivity of the ME composites with the 36 piezoelectric vibration mode was up to 2 nT and those of the ME composites with the 31 and 32 piezoelectric vibration modes were up to 5 nT. These magnetic-field sensitivities are similar to those offered by conventional high-sensitivity magnetic-field sensors; the potential of the proposed sensor to replace costly and bulky high-sensitivity magnetic field sensors is significant.

• International Journal of Concrete Structures and Materials
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• v.8 no.4
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• pp.301-307
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• 2014

Rice husk ash (RHA) is classified as a highly reactive pozzolan. It has a very high silica content similar to that of silica fume (SF). Using less-expensive and locally available RHA as a mineral admixture in concrete brings ample benefits to the costs, the technical properties of concrete as well as to the environment. An experimental study of the effect of RHA blending on workability, strength and durability of high performance fine-grained concrete (HPFGC) is presented. The results show that the addition of RHA to HPFGC improved significantly compressive strength, splitting tensile strength and chloride penetration resistance. Interestingly, the ratio of compressive strength to splitting tensile strength of HPFGC was lower than that of ordinary concrete, especially for the concrete made with 20 % RHA. Compressive strength and splitting tensile strength of HPFGC containing RHA was similar and slightly higher, respectively, than for HPFGC containing SF. Chloride penetration resistance of HPFGC containing 10-15 % RHA was comparable with that of HPFGC containing 10 % SF.

• Fisheries and Aquatic Sciences
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• v.14 no.4
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• pp.303-310
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• 2011

We characterized a cytoplasmic actin gene locus in greenling Hexagrammos otakii (Scorpaeniformes). Genomic clones isolated from the greenling DNA library contained two homologous cytoplasmic actin gene copies (HObact2.1 and HObact2.2) in a tail-to-head orientation. Their gene structure is characterized by six translated exons and one non-translated exon. Exon-intron organization and the nucleotide sequences of the two actin gene isoforms are very similar. However, only the HObact2.1 isoform contains microsatellite-like, dinucleotide repeats in the 5'-flanking region (named HOms2002) and intron 1 following the non-translated exon 1 (named HOms769). One microsatellite locus (HOms769) was highly polymorphic while the other (HOms2002) was not. Based on bioinformatic analysis, different transcription factor binding motifs are related to stress and immune responses in the two actin isoforms. Semiquantitative and real-time reverse transcription-PCR assays showed that both isoform transcripts were detectable ubiquitously in all the tissues examined. However, the basal expression levels of each isoform varied across tissues. Overall, the two isoforms showed a similar, but not identical, expression pattern. Our data suggest that the cytoplasmic actin genes may be the result of a recent duplication event in the greenling genome, which has not experienced significant subfunctionalization in their housekeeping roles.

• Ceramist
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• v.22 no.4
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• pp.357-367
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• 2019

Secondary Ion Mass Spectrometry(SIMS) is an analytical method that measures the distribution and concentration of elements or compounds by analyzing the mass of secondary ions released by irradiating ion beams with energy of hundreds eV to 20 keV on the sample surface. Unlike other similar analytical instruments, SIMS directly detect the elemental ions that constitute a sample, allowing you to accurately identify components and obtain concentration information in the depth direction. It is also a great feature for measuring isotopes and analyzing light elements, especially hydrogen. In particular, with the development of materials science, there is an increasing demand for trace concentration analysis and isotope measurements in the micro-regions of various materials. SIMS has a short history compared to other similar methods; nevertheless, SIMS is still advancing in hardware and is expected to contribute to the development of materials science through research and development of advanced analytical techniques.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.1
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• pp.1063-1066
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• 2005

Most reading systems that supply various study data generally support keyword search. But the usual keyword matching techniques have a problem to require the exact keyword matching, and could not find similar field materials. Futhermore, testing materials have too little information to apply the keyword matching search. To solve these problems, this thesis proposes the method to extract the important keyword from study data and to construct the database automatically when the data are stored at the storage. And using prepared similar terminology database, we suggest the intelligent and efficient technique to find study materials.

• Korean Journal of Metals and Materials
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• v.49 no.3
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• pp.250-255
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• 2011

The basic properties and electrical characteristics of sputtering films deposited with a commercial cast target and Spark Plasma Sintering (SPS) were compared and analyzed. From the results, the Cu film prepared heating $60^{\circ}C/min$ (SPS process) showed a similar specific resistance compared to the commercial cast Cu film. Also, auording to the results of XRD, SIMS, and TEM. There was not much difference in the crystal structure and impurities between the two films. Consequently, the SPS Cu target was found to have quite similar properties with the commercial one and it is expected to be applied in futare research to the metal wiring material for semiconductor/display devices.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.05a
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• pp.53-54
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• 2021

Grenfell Tower was renovated in 2014 and 2016 at a high cost to replace the exterior materials, windows and co-heating facilities of the building. The exterior materials used during the repair work were sandwich panels filled with polyethylene and plastic, which were expanded on the aluminum metal surface. It is a product called Celotex RS 5000, a low-resolution but inexpensive repair material, and is currently an external material that cannot be used in high-rise buildings. Similar domestic fire cases began to focus social attention on the safety of high-rise buildings through the Busan Residential Complex Fire (2010), Uijeongbu Urban Living Housing Fire (2015), and Ulsan Residential Complex Fire (2020), and residents' safety concerns are increasing. In Korea, the occurrence and risk of similar fires are high, so setting up fire prevention measures through fire case investigation is considered the most basic measure in securing human safety. Therefore, the purpose of this study is to examine the status of fire damage caused by domestic and foreign eruptions, domestic and international research status and related regulations on external materials and windows starting from the Grenfell Tower fire in England.

• Journal of the Korean Home Economics Association
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• v.42 no.6
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• pp.111-121
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• 2004

This study focused on the development of creative materials by applying tapestry to produce original and high-grade dresses with consideration the modems' tendency to place high value on personal taste and style. The development remained sensitive to current trends and attempted to expand into high value-added dresses. Materials in modem fashion design, as a basis of the fashion industry, can lead to a current of new fashion and produce novel and creative ideas by stimulating the designers' creativity. Designers can diversely express a form according to their intention, since tapestry allows the expression of various feelings of texture and forms according to the combination mode of technique, structure and materials on a basic plane. Moreover, tapestry encrourages the development of varied designs because it can effectively display the texture and color of a textile surface through the careful selection of materials even under the same technique. Tapestry can apply forms similar to a textile's basic structure to fashion design and can create high added value with the merit of being 'handmade'.

• ETRI Journal
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• v.31 no.6
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• pp.703-708
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• 2009

Silicon antimony films are studied as resistors for uncooled microbolometers. We present the fabrication of silicon films and their alloy films using sputtering and plasma-enhanced chemical vapor deposition. The sputtered silicon antimony films show a low 1/f noise level compared to plasma-enhanced chemical vapor deposition (PECVD)-deposited amorphous silicon due to their very fine nanostructure. Material parameter K is controlled using the sputtering conditions to obtain a low 1/f noise. The calculation for specific detectivity assuming similar properties of silicon antimony and PECVD amorphous silicon shows that silicon antimony film demonstrates an outstanding value compared with PECVD Si film.

• Archives of Metallurgy and Materials
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• v.66 no.4
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• pp.1023-1027
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• 2021

This study investigated the effect of flux type and amounts on recovery behavior of aluminum alloy during the melting process of Al can scrap. The heat treatment was conducted to remove the coating layer on the surface of can scrap at 500℃ for 30 min. The molten metal treatment of the scrap was performed at 750℃ in a high-frequency induction furnace with different flux types and amounts. It was observed that the optimum condition for recovery of Al alloy was to add about 3 wt.% flux with a salt and MgCl₂ mixing ratio of 70:30 during melting process. The mechanical properties of recovered Al alloy were about 254.8 MPa, which is similar to that of the virgin Al5083 alloy.