• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.3
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• pp.49-55
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• 2019

An open office or a shared office is emerging as the emphasis on the collaborative and communicative work environments is increasing. In the past, the user maintained the space, but the maintenance of indoor space became difficult because there is no fixed user. Indoor space information can be collected using the ICBM framework system. The facility management can achieve this with data. Therefore, this study proposed a framework based on ICBM (Internet of Things, Cloud, Big Data, and Mobile) for verifying the possibility of a smart facility management system for indoor space. IoT (Internet of Things) technology was used to measure the indoor temperature, humidity, occupancy, and brightness continuously, and provided the data to Web API via WiFi. Data acquired automatically via IoT, existing maintenance data, and spatial information were integrated through the Cloud. Big data collected by sensors were processed as meaningful spatial information for maintenance. Indoor space information and maintenance information can be delivered to the manager through the mobile. Based on the collected data, room occupancy recognition is limited due to a range of ultrasonic wave sensors. On the other hand, brightness represents the space conditions. The difference between lighting on/off, weekday and weekend can be shown. The temperature data and the relative humidity data were collected steadily to evaluate the comfort.

• Journal of Platform Technology
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• v.6 no.4
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• pp.59-68
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• 2018

The objective of this study is to develop an embedded antenna structure with NFC and WPC composite functions. By selecting stable materials, the optimal component ratio of the polymer sheet was determined. The low cost embedded winding method compared to the existing FPCB was devised. During the winding process, characterization and process technology were developed. We also fabricated a ferrite mold to process the WPC grooves and developed the process technology for optimizing the WPC antenna. The following conclusions were obtained. (1) Optimum composition ratio was derived as Fe 87.5%, Si 7%, Al 5.5% and selected as the final material. (2) Optimal sheet conditions were derived from the experimental evaluation method and the experimental design method through the combination test of the optimized sheet and the conventional mass production FPCB. (3) According to coil diameter and inner diameter, Q value fluctuation, resistance value and efficiency fluctuation are obtained. Therefore, the most suitable coil condition is selected and Rx matching is performed. (4) The EMV load modulation test and the cognitive distance test of the polymer sheet and the ferrite sheet showed that the recognition distance of the polymer sheet at 1k and 4K was 32-33 mm and the recognition distance of the ferrite sheet at the same condition was 30-31 mm.

• Journal of Korean Society of Disaster and Security
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• v.11 no.2
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• pp.53-60
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• 2018

To diagnosis the local damages of the steel plates, magnetic flux leakage (MFL) method that is known as a adaptable non-destructive evaluation (NDE) method for continuum ferromagnetic members was applied in this study. To analysis the sensitivity according to thickness of steel plate in MFL method based damage diagnosis, several steel plate specimens that have different thickness were prepared and three depths of artificial damage were formed to the each specimens. To measured the MFL signals, a MFL sensor head that have a constant magnetization intensity were fabricated using a hall sensor and a magnetization yoke using permanent magnets. The magnetic flux signals obtained by using MFL sensor head were improved through a series of signal processing methods. The capability of local damage detection was verified from the measured MFL signals from each damage points. And, the peak to peak values (P-P value) extracted from the detected MFL signals from each thickness specimen were compared each other to analysis the MFL based local damage detection sensitivity according to the thickness of steel plate.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.9
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• pp.465-473
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• 2019

This paper is meaningful as the first case where a 4 - sided hull-fixed phased array radar was installed on a mast separated from Korea and the alignment was verified. The mechanical alignment method was studied for accurately mounting two separate masts for naval ships and the 3D scanner for alignment. Hull-fixed phased array radar uses very high frequency, so the short wavelength can cause a phase difference of the device due to the small positional error. Since the array antenna is fixed with the hull, it has higher accuracy control than the rotary radar for 4 array surfaces. The study describes a method of checking the flatness of two radar masts manufactured at a factory, a method of aligning masts in a shipyard, and a method of aligning four array pad mounting surfaces. As a tool for this, a 3D laser scanner and a software-based method for comparing survey results with 3D CAD are used. This paper is meaningful as the first example of installing a four-sided hull-fixed phased array radar on a separate mast from a Korean naval ship and deriving a mechanical alignment method.

• Journal of Food Hygiene and Safety
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• v.36 no.4
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• pp.289-297
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• 2021

In this study, multiplex PCR and real-time PCR were performed on Theragra chalcogramma (walleye pollock), Pangasianodon hypophthalmus (iridescent shark) and their processed foods, such as changnan-jeot and gaiyang-jeot (salted iridescent shark intestine). Species-specific primers for T. chalcogramma and P. hypophthalmus were designed, and genomic DNA was directly extracted from each sample to perform single PCR and multiplex PCR. As a result of PCR, in the case of single PCR, PCR bands of T. chalcogramma (297 bp) and P. hypophthalmus (132 bp) were identified, and in the case of multiplex PCR, it was confirmed that amplification occurred without cross-reaction between T. chalcogramma and P. hypophthalmus. As a result of checking the PCR sensitivity, the concentration of genomic DNA was detected up to 0.1 ng/µL in both single PCR and multiplex PCR. The real-time PCR results showed that the average Ct value of T. chalcogramma was 20.765±0.691, and the average Ct value of P. hypophthalmus sample was 35.719±1.828 in the T. chalcogramma species-specific primers. In the P. hypophthalmus species-specific primers, the average Ct value of the T. chalcogramma sample was 35.996±1.423, and the mean Ct value of the P. hypophthalmus sample was 20.096±0.793. These results demonstrated the significant differences in the efficiency, specificity and cross-reactivity of species-specific primers in real-time PCR. Based on these findings, 7 of changnan-jeot or gaiyang-jeot products were confirmed by multiplex PCR and real-time PCR, and valid results were confirmed in all samples.

• Journal of Dental Rehabilitation and Applied Science
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• v.38 no.3
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• pp.127-137
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• 2022

Zirconia is fabricated through various processes. Each element in fabricating process can affect the physical properties of the definitive prosthesis. In particular, both the milling process and the sintering process can affect the final integrity of the zirconia prosthesis. Most of the milling machines adopt the ultra-precision 5-axis machining method, and the results vary depending on which milling method was used and how the milling equipment was managed. Milling blocks are selected according to cutting efficiency and aesthetic reproducibility. The sintering method can affect the grain growth and optical properties, and an accurate evaluation can be made only with additional research on the recent speed sintering procedure. Not only the sintering temperature but also the temperature holding time can affect the quality of definitive prosthesis.

• Korean Journal of Environmental Biology
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• v.39 no.4
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• pp.445-451
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• 2021

In this study, we described the production of an antibody to living modified organisms (LMOs) containing the gene encoding for 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) from Agrobacterium tumefaciens strain CP4 EPSPS provides resistance to the herbicide glyphosate (N- (phosphonomethyl) glycine). These LMOs were approved and have recently been used in the feed, food production, and processing industries in South Korea. Highly efficient monoclonal antibody (mAb) production is crucial for developing assays that enable the proper detection and quantification of the CP4 EPSPS protein in LMOs. This study describes the purification and characterization of recombinant CP4 EPSPS protein in E. coli BL21 (DE3) based on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and matrixassisted laser desorption/ionization time-of-flight mass spectrometry. The production of mAbs was undertaken based on the standard operating procedure of Abclon, Inc.(South Korea), and the purity of the mAbs was assessed using SDS-PAGE. The following five mAb clones were produced: 2F2, 4B9, 6C11, 10A9, and 10G9. To verify the efficiency and specificity of the five developed mAbs, we performed Western blotting analysis using the LM (living modified) cotton crude extracts. All mAbs could detect the CP4 EPSPS protein in the LM cotton traits MON1445 and MON88913 with high specificity, but not in any other LM cottons or non-LM cottons. These data indicate that these five mAbs to CP4 EPSPS could be successfully used for the further development of antibody-based detection methods to target CP4 EPSPS protein in LMOs.

• Journal of the Microelectronics and Packaging Society
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• v.30 no.2
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• pp.65-70
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• 2023

Nanoimprint lithography (NIL) has attracted much attention due to its process simplicity, excellent patternability, process scalability, high productivity, and low processing cost for pattern formation. However, the pattern size that can be implemented on metal materials through conventional NIL technologies is generally limited to the micro level. Here, we introduce a novel hard imprint lithography method, extreme-pressure imprint lithography (EPIL), for the direct nano-to-microscale pattern formation on the surfaces of metal substrates with various thicknesses. The EPIL process allows reliable nanoscopic patterning on diverse surfaces, such as polymers, metals, and ceramics, without the use of ultraviolet (UV) light, laser, imprint resist, or electrical pulse. Micro/nano molds fabricated by laser micromachining and conventional photolithography are utilized for the nanopatterning of Al substrates through precise plastic deformation by applying high load or pressure at room temperature. We demonstrate micro/nanoscale pattern formation on the Al substrates with various thicknesses from 20 ㎛ to 100 mm. Moreover, we also show how to obtain controllable pattern structures on the surface of metallic materials via the versatile EPIL technique. We expect that this imprint lithography-based new approach will be applied to other emerging nanofabrication methods for various device applications with complex geometries on the surface of metallic materials.

• Composites Research
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• v.36 no.3
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• pp.167-172
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• 2023

The manufacturing technology of composite material is applicable with filler characteristics maintaining low cost, flexibility, and easy process to develope the various functional composite materials. To realize functional composites, various researches on the high performance of composite materials using graphene as a filler is being actively conducted. In this study, physical and chemical properties were investigated using graphene to improve high functional properties. Graphene oxide (GO) was prepared using graphane nanoplatelet (GNP), and reduced graphene oxide (R-GO) was formed by reducing GO. The physical properties of GO and R-GO were analyzed, and the reliability of the manufactured method was reviewed by comparing that of GNP results. As a result of analysis by Raman spectroscopy, in the case of R-GO, it was confirmed that the intensity of D-peak and G-peak decreased compared to GO, and an increase of 0.08 was observed through the ratio of ID/IG. For the FTIR results, GO and RGO has a repeating C-C and C=C connection structure unlike GNP. GO and R-GO show clear peaks for C-O bond, C=C bond, C=O bond, and O-H bonding. As a result of X-ray diffraction analysis, GNP showed a wide diffraction peak at 25.86° of (002) plane characteristics, whereas GO and R-GO showed peaks corresponding to (001) and (100) planes. It was also found that the interlayer distance of GO increased by about 2.6 times compared to GNP.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.24 no.2
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• pp.65-71
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• 2018

Paper packs, glass bottles, metal cans, and plastic materials are classified according to packaging material recycling groups that are Extended Producer Responsibility (EPR). In the case of waste paper pack, the compressed cartons are dissociated to separate polyethylene films and other foreign substance, and then these are washed, pulverized and dried to produce toilet paper. Glass bottle for recycling is provided to the bottle manufacturers after the process of collecting the waste glass bottle, removing the foreign substance, sorting by color, crushing, raw materializing process. Waste glass recycling technology of Korea is largely manual, except for removal of metal components and low specific gravity materials. Metal can is classified into iron and aluminum cans through an automatic sorting machine, compressed, and reproduced as iron and aluminum through a blast furnace. In the case of composite plastic material, the selected compressed product is crushed and then recycled through melt molding and refined products are produced through solid fuel manufacturing steps through emulsification and compression molding through pyrolysis. In the recycling process of paper packs, glass bottles, metal cans, and plastic materials, the influx of recycled materials and other substances interferes with the recycling process and increases the recycling cost and time. Therefore, the government needs to improve the legal system which is necessary to use materials and structure that are easy to recycle from the design stage of products or packaging materials.