• Journal of Welding and Joining
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• v.34 no.2
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• pp.30-35
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• 2016

Last few decades have seen a rapid increase in the fabrication and characterization of Al alloys for automobiles, heat exchangers and aerospace industries. Aluminium alloys are popular because of their high specific strength, light weight, excellent wear and high oxidation resistance. The development of aluminium alloys in these applications makes their study and research of utmost importance. Brazing is applied to the aluminium alloys for joining various aluminium parts together in most of the industrial applications. Various parameters affect the joining process of these aluminium alloys. In this article, various types of processing parameters have been discussed, and special attention has been given to the category of aluminium brazing alloys. The article reviews on the various parameters that affect the brazing property in various scientific and technological applications.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.06a
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• pp.322-322
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• 2008

Low-temperature co-fired ceramics (LTCC) have turned out to be very promising technology in accordance with the rapid developments in semiconductor technology. The demands for compact electrical assemblies, smaller power loss as well as high signal density can be fulfilled by LTCC. And for the multi-layered ceramic devices with embedded passive components such as high dielectric constant decoupling capacitor, LTCC materials require the several conditions to avoid delamination and internal cracks. For the present study, diopside-based glass is chosen as the LTCC substrate material in view of its high coefficient of thermal expansion (CTE). From the experimental resultsn the influence of each element on the CTE change can be revealed.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08a
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• pp.937-939
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• 2007

Carbon nanotubes (CNTs) have used as an electron field emitter of the field emission display (FED) due to their characteristics of high-electron emission, rapid response and low power consumption. However, to commercialize the FED with CNT emitter, some fundamental problems regarding life time and emission efficiency have to be solved. In this study, we investigated the $TiO_2$ coated CNT as a field emitter. $TiO_2$ nanoparticles can coated on CNT surface by chemical solution method. $TiO_2$ nanoparticles had uniform size with the average size of about 2.4 nm to 3.1 nm. Field emission performance of CNT coated with $TiO_2$ nanoparticles was evaluated and discussed.

• 한국전산유체공학회:학술대회논문집
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• 2002.10a
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• pp.8-16
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• 2002

Now, the era of information, the rapid acquisition of vast and various information acts as a key role. for the national competitiveness. The smart UAV is brought to the fore as a new future technology which will be able to satisfy the information needs in broad and stereoscopic manner. The smart UAV, with VTOL capability, higher performance, and reliability over the existing technology thresholds, will lead the aerospace technology in the future. In this paper, the technology concept of smart UAV, the necessity of development, and the trend of worldwide R&D are introduced and analyzed. In addition, for the Smart UAV Development Program which is launched by the 21c Frontier R&D program this year, the role and application area of the CFD will be discussed.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.20 no.5
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• pp.1-7
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• 2021

In recent years, automated process technology has allowed for the rapid manufacturing of metal parts. Maintaining high product quality is of vital importance during the production of these parts. Surface defects occurring after processing can compromise their assembly precision and performance. In this study, a deburring tool was developed that can remove burrs generated from drilling. Through the evaluation of processing, burrs were completely removed at entrance and exit surfaces. Therefore, this newly developed deburring tool shows better performance than deburring tools currently in use.

• Asian Journal of Innovation and Policy
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• v.12 no.3
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• pp.345-362
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• 2023

As the widespread adoption and proliferation of electric vehicles continue, the secondary battery market is experiencing rapid growth. However, lithium-ion batteries, which constitute a majority of secondary batteries, present high risks of fire and explosion. Solid-state batteries are thus garnering attention as the next-generation batteries since they eliminate fire hazards and significantly reduce the risk of explosions. Against this background, the study aimed to analyze research trends and provide insights by examining 2,927 domestic papers related to solid-state batteries over the past decade (2013-2022). Specifically, we used topic modeling to extract major keywords associated with solid-state batteries research and to explore the network characteristics across major topics. The changes in research on solid-state batteries were analyzed in-depth by calculating topic dominance by year. The findings provide an overview of the emerging trends in domestic solid-state battery research, and might serve as a valuable reference in shaping long-term research directions.

• Polymer(Korea)
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• v.38 no.1
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• pp.93-97
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• 2014

Biodegradable drug-eluting stent has dual functions of supporting the lumen and treating internal tumor preventing the restenosis by releasing drug. In this study, the polycaprolactone (PCL) based three dimensional (3D) mesh loaded with paclitaxel (PTX) was presented by rapid prototyping (RP) technique of solid freeform fabrication (SFF) for biodegradable drug-eluting stent application. PCL has many advantageous properties such as good biocompatibility, good mechanical properties, and good drug permeability. PTX is widely used in the cancer treatment by inhibiting tumor cell proliferation. Analytical methods of HPLC and NMR were used for simultaneous quantification of PTX. Scanning electron microscopy (SEM) was performed to observe the architecture and morphologies of 3D mesh. The cytotoxicity assay results indicated released PTX's biological activity. This study provided that PCL based 3D mesh loaded with PTX by RP technique has great potential for biodegradable drug-eluting stent application.

• Proceedings of the Korea Contents Association Conference
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• 2009.05a
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• pp.748-753
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• 2009

Large amounts of research results are being produced with the rapid growth of science and technology. The current method for constructing the database was way too time and cost consuming. In the currently upcoming technology and knowledge society, web service is required to provide the various professional service for national R&D reports. A process to manufacture E-Book for professional service is also required. This research shows the conversion models with efficient manufacturing process and the systems related to the development through defining the National R&D reports.

• BMB Reports
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• v.39 no.5
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• pp.502-510
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• 2006

2C-methyl-D-erythritol 2, 4-cyclodiphosphate synthase (MECPS, EC: 4.6.1.12) is the fifth enzyme of the non-mevalonate terpenoid pathway for isopentenyl diphosphate biosynthesis and is involved in the methylerythritol phosphate (MEP) pathway for ginkgolide biosynthesis. The full-length mecps cDNA sequence (designated as Gbmecps) was cloned and characterized for the first time from gymnosperm plant species, Ginkgo biloba, using RACE (rapid amplification of cDNA ends) technique. The full-length cDNA of Gbmecps was 874 bp containing a 720 bp open reading frame (ORF) encoding a peptide of 239 amino acids with a calculated molecular mass of 26.03 kDa and an isoelectric point of 8.83. Comparative and bioinformatic analyses revealed that GbMECPS showed extensive homology with MECPSs from other species and contained conserved residues owned by the MECPS protein family. Phylogenetic analysis indicated that GbMECPS was more ancient than other plant MECPSs. Tissue expression pattern analysis indicated that GbMECPS expressed the highest in roots, followed by in leaves, and the lowest in seeds. The color complementation assay indicated that GbMECPS could accelerate the accumulation of $\beta$-carotene. The cloning, characterization and functional analysis of GbMECPS will be helpful to understand more about the role of MECPS involved in the ginkgolides biosynthesis at the molecular level.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.21 no.9
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• pp.519-526
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• 2009

Environmental control system is adopted to control the thermal load from the avionic equipment in the reconnaissance pod which is mounted under a fighter aircraft, undergoing large and rapid environmental changes with the variations of flight altitude and velocity. In this study, an environmental control system was designed and built by adopting vapor compression cycle using R-124. The cooling performance characteristics of the system were measured varying operating parameters: thermal load in the pod, air mass flow rate through evaporator, condenser inlet air temperature, and air mass flow rate through condenser. The effects of the experimental parameters on the system performance were analyzed based on the experimental results. The problems on the designed system were also analyzed and the solutions were suggested to improve system efficiency and to obtain stable operation.