Cu matrix composites reinforced with chopped carbon fiber (CF), which is cost effective and can be well dispersed, are fabricated using electroless plating and hot pressing, and the effects of content and alignment of CF on the thermal properties of CF/Cu composites are studied. Thermal conductivity of CF/Cu composite increases with CF content in the in-plane direction, but it decreases above 10% CF; this is due to reduction of thermal diffusivity related with phonon scattering by agglomeration of CF. The coefficient of thermal expansion decreases in the in-plane direction and increases in the through-plane direction as the CF content increases. This is because the coefficient of thermal expansion of the long axis of CF is smaller than that of the Cu matrix, and the coefficient of thermal expansion of its short axis is larger than that of the Cu matrix. The thermal conductivity is greatly influenced by the agglomeration of CF in the CF/Cu composite, whereas the coefficient of thermal expansion is more influenced by the alignment of CF than the aggregation of CF.

본 연구에서는 게임 동영상의 고화질 변환이 가능한 초해상화 알고리즘을 제시한다. 본 알고리즘은 오픈 소 스 형태의 GPU에서 제공하는 MMU에서 구현될 수 있도록 희소 행렬 연산을 이용해서 설게된다. 이를 위해 서 일반적인 영상 해상도 향상 방법인 이중 일차 및 이중 삼차 보간 법과 심층 학습에 기반한 초해상화 모 델에서 사용하는 컨볼루션 연산을 희소 행렬 연산으로 변환하는 방법을 제시한다. 이는 각 픽셀에 적용되는 필터를 행렬 곱 형태로 표현하고, 이 행렬을 희소 행렬로 표현함으로써 수행되는데, 이러한 과정을 통해서 연산의 효율성을 추구함으로써 안정적인 초해상화 알고리즘을 제공한다. 이러한 희소행렬 연산 형태로 표현 되는 초해상화 알고리즘은 기존의 라이브러리를 이용해서 구현된 초해상화 알고리즘과 유사한 PSNR과 FPS 를 보인다.

Composite materials offer distinct and unique properties that are not naturally inherited in the individual materials that make them. One of the most attractive composites to manufacture is the aluminum alloy matrix composite, because it usually combines easiness of availability, light weight, strength, and other favorable properties. In the current work, Powder Metallurgy Method (PMM) is used to prepare Al2024 matrix composites reinforced with different mixing ratios of yttrium oxide (Y2O3) particles. The tests performed on the composites include physical, mechanical, and tribological, as well as microstructure analysis via optical microscope. The results show that the experimental density slightly decreases while the porosity increases when the reinforcement ratio increases within the selected range of 0 ~ 20 wt%. Besides this, the yield strength, tensile strength, and Vickers hardness increase up to a 10 wt% Y2O3 ratio, after which they decline. Moreover, the wear results show that the composite follows the same paradigm for strength and hardness. It is concluded that this composite is ideal for application when higher strength is required from aluminum composites, as well as lighter weight up to certain values of Y2O3 ratio.

Understanding of effects of changes in the particle size of the matrix material on the mullite whisker growth during the production of porous mullite is crucial for better design of new porous ceramics materials in different applications. Commercially, raw materials such as Al2O3/SiO2 and Al(OH)3/SiO2 are used as starting materials, while AlF3 is added to fabricate porous mullite through reaction sintering process. When Al2O3 is used as a starting material, a porous microstructure can be identified, but a more developed needle shaped microstructure is identified in the specimen using Al(OH)3, which has excellent reactivity. The specimen using Al2O3/SiO2 composite powder does not undergo mulliteization even at 1,400 oC, but the specimen using the Al(OH)3/SiO2 composite powder had already formed complete mullite whiskers from the particle size specimen milled for 3 h at 1,100 oC. As a result, the change in sintering temperature does not significantly affect formation of microstructures. As the particle size of the matrix materials, Al2O3 and Al(OH)3, decreases, the porosity tends to decrease. In the case of the Al(OH)3/SiO2 composite powder, the highest porosity obtained is 75% when the particle size passes through a milling time of 3 h. The smaller the particle size of Al(OH)3 is and the more the long/short ratio of the mullite whisker phase decreases, the higher the density becomes.

There is increasing demand for the development of a new material with high strength, high stiffness, and good electrical conductivity that can be used for high-voltage direct current cables. In this study, we develop aluminumbased composites containing C60 fullerenes, carbon nanotubes, or graphene using a powder metallurgical route and evaluate their strength, stiffness, coefficient of thermal expansion, and electrical conductivity. By optimizing the process conditions, a material with a tensile strength of 800 MPa, an elastic modulus of 90 GPa, and an electrical conductivity of 40% IACS is obtained, which may replace iron-core cables. Furthermore, by designing the type and volume fraction of the reinforcement, a material with a tensile strength of 380 MPa, elastic modulus of 80 GPa, and electrical conductivity of 54% IACS is obtained, which may compete with AA 6201 aluminum alloys for use in all-aluminum conductor cables.

Periodontal disease is an inflammatory disease that affects the destruction of the bone supporting the tooth and connective tissues surrounding it. Periodontal ligament fibroblasts (PDLFs) induce overexpression of matrix metalloproteinase (MMP) involved in periodontal diseaseʼs inflammatory destruction. Osteoclasts take part in physiological bone remodeling, but they are also involved in bone destruction in many kinds of bone diseases, including osteoporosis and periodontal disease. This study examined the effect of baicalin on proteolytic enzymesʼ production and secretion of inflammatory cytokines in PDLFs and RAW 264.7 cells under the lipopolysaccharide (LPS)-induced inflammatory conditions. Baicalin inhibited the expression of the protein, MMP-1 and MMP-2, without affecting PDLFs’ cell viability, suggesting its possibility because of the inhibition of phosphorylation activation of mitogen-activated protein kinase’s p38, and the signal transduction process of nuclear factor κB (NFκB)-related protein. Also, baicalin reduced the expression of MMP-8 and MMP-9 in RAW 264.7 cells. This reduction is thought to be due to the inhibition of the signal transduction process of NFκB-related proteins affected by inhibiting p65RelA phosphorylation. Also, baicalin inhibited the secretion of nitric oxide and interleukin-6 induced by LPS in RAW 264.7 cells. These results suggest that baicalin inhibits connective tissue destruction in periodontal disease. The inhibition of periodontal tissue destruction may be a therapeutic strategy for treating inflammatory periodontal-diseased patients.

이온성 액체 기반 혼합 멤브레인(MMM)은 이산화탄소 분리 매체로써 다양한 종류의 이온성 액체와 무기성 필러 폴리머에 의해 만들어진다. 이온성 액체와 무기성 필러의 강한 상호작용은 이산화탄소의 금속 유기체의 프레임워크 내 친화 력, 선택성, 흡착성을 높여 분리성능을 향상시킨다. 또, 이온성 액체에 의해 혼합 매트릭스 멤브레인의 구조적 특성이 조절되 어 이산화탄소 투과성과 선택성을 향상시킨다. 이 리뷰에서는 이산화탄소 분리를 위한 고분자 막에서의 이온성 액체(IL)와 금속 유기체 프레임워크(MOF)의 다양한 조합에 대한 연구가 논의될 것이다.

Recently, a multi facility, multi product and multi period industrial problem has been widely investigated in Supply Chain Network(SCN). One of keys issues in the current SCN research area involves minimizing both production and distribution costs. This study deals with finding an optimal solution for minimizing the total cost of production and distribution problems in supply chain network. First, we presented an integrated mathematical model that satisfies the minimum cost in the supply chain. To solve the presented mathematical model, we used a genetic algorithm with an excellent searching ability for complicated solution space. To represent the given model effectively, the matrix based real-number coding schema is used. The difference rate of the objective function value for the termination condition is applied. Computational experimental results show that the real size problems we encountered can be solved within a reasonable time.