• Korean Journal of Optics and Photonics
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• v.4 no.4
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• pp.420-427
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• 1993

Dielectric thin film mirrors are embedded in multimode and single-mode fibers by a fusion splicing technique. The fibers with $45{\circ}$ angled embedded mirrors serve as ultra-compact directional couplers with low excess optical loss of 0.2 dB for multimode and 0.5 dB for single mode at 1.3 ${\mu}m$ and excellent mechanical properties. The reflectance is wavelength dependent and strongly polarization depencient. Far-field scans of the reflected output power measured with a white-light source show a pattern which is almost circularly symmetric with aspect ratio of 1.09 at 5% of the peak power. The splitting ratio in a multimode coupler measured with a diode laser source is much less dependent on input coupling conditions than in conventional fused biconical-taper couplers, indicating that these couplers are less susceptible to modal noise occuring in optical fiber communication systems. Spectral properties of multilayer internal mirrors normal to the fiber axis have been investigated experimentally, and a matrix analysis has been used to explain the results.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2008.11a
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• pp.767-771
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• 2008

From industrial field spearhead IT and new create an added value and market with fusion of traditional industry composition researches actively to be in the process of advancing. The application possibility of high-tech IT technique is coming to be high in construction industry. Currently, the user requirements that upgrade existing system to high-tech construction project information system combined construction CALS system applying in road/river business management service with high-tech IT such as ubiquitous and mobile techniques are increasing. Therefore, the objective of this study is to verify site application of RFID and mobile equipment for applying in high-tech field with ubiquitous and mobile techniques so that construction CALS system gets advanced increasingly.

• The Journal of the Korea Contents Association
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• v.14 no.9
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• pp.45-53
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• 2014

In this study, we analyzed the next generation ITS (C-ITS) technology trends, focusing on the national and international C-ITS projects. Based on the promotion practices of developed countries, we pointed out the lack of linkages with the existing ITS infrastructure. As a way to overcome this problem, we proposed the three-direction to enable the existing ITS infrastructure corresponding to the C-ITS. First one is developing a technique to improve the performance of the existing ITS infrastructure and automate the performance management (Performance-enhanced ITS). Second, developing active sensors or fusion sensor which along with V2X communication technology implement of an active safety driving support system (Safety-enhanced ITS). Third, we need to develop a technology that generate the new advanced traffic data by integrating the collected data from existing ITS infrastructure and nomadic device (Cloud-ITS). By improving the function of the existing ITS infrastructure for adaptation to the new V2X communication environment, we enhanced the efficiency of maintenance performance and would maximize the benefit of the introduction of C-ITS.

• Journal of Microbiology and Biotechnology
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• v.23 no.7
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• pp.942-952
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• 2013

Monoliths are functional porous materials with a three-dimensional continuous interconnected pore structure in a single piece. A monolith with uniform shape based on poly(${\gamma}$-glutamic acid) (PGA) has been prepared via a thermally induced phase separation technique using a mixture of dimethyl sulfoxide, water, and ethanol as solvent. The morphology of the obtained monolith was observed by scanning electron microscopy and the surface area of the monolith was evaluated by the Brunauer Emmett Teller method. The effects of fabrication parameters such as the concentration and molecular mass of PGA and the solvent composition have been systematically investigated. The PGA monolith was cross-linked with hexamethylene diisocyanate to produce the water-insoluble monolith. The addition of sodium chloride to the phase separation solvent affected the properties of the cross-linked monolith. The swelling ratio of the cross-linked monolith toward aqueous solutions depended on the buffer pH as well as the monolith fabrication condition. Copper(II) ion was efficiently adsorbed on the cross-linked PGA monolith, and the obtained copper-immobilized monolith showed strong antibacterial activity for Escherichia coli. By combination of the characteristic properties of PGA (e.g., high biocompatibility and biodegradability) and the unique features of monoliths (e.g., through-pore structure, large surface area, and high porosity with small pore size), the PGA monolith possesses large potentials for various industrial applications in the biomedical, environmental, analytical, and separation fields.

• Journal of international Conference on Electrical Machines and Systems
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• v.3 no.1
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• pp.78-82
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• 2014

Power Transformers with more than one secondary winding are not uncommon in industrial applications. But new classes of applications where very large number of independent secondaries are used are becoming popular in controlled converters for medium and high voltage applications. Cascade H-bridge medium voltage drives and Pulse Step Modulation (PSM) based high voltage power supplies are such applications. Regulated high voltage power supplies (Fig. 1) with 35-100 kV, 5-10 MW output range with very fast dynamics (${\mu}S$ order) uses such transformers. Such power supplies are widely used in fusion research. Here series connection of isolated voltage sources with conventional switching semiconductor devices is achieved by large number of separate transformers or by single unit of multi-secondary transformer. Naturally, a transformer having numbers of secondary windings (~40) on single core is the preferred solution due to space and cost considerations. For design and simulation analysis of such a power supply, the model of a multi-secondary transformer poses special problem to any circuit analysis software as many simulation softwares provide transformer models with limited number (3-6) of secondary windings. Multi-Secondary transformer models with 3 different schemes are available. A comparison of test results from a practical Multi-secondary transformer with a simulation model using magnetic component is found to describe the behavior closer to observed test results. Earlier models assumed magnetising inductance in a linear loss less core model although in actual it is saturable core made-up of CRGO steel laminations. This article discusses a more detailed representation of flux coupled magnetic model with saturable core properties to simulate actual transformers very close to its observed parameters in test and actual usage.

• Journal of Digital Convergence
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• v.14 no.12
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• pp.267-281
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• 2016

This study analyzed the contents of articles on GMO in Chosun Ilbo and Hankyoreh from 1994 through 2015 to check the trend of reporting on GMO as a science and technology risk issue. As a result, 'risk' and 'anxiety/concern' were continuously treated as important subjects, and there was a lack of depth and journalist's professionalism in all three periods: 'Introduction of GMO technology (1994-2000)', 'Development of GMO technology (2001-2010)' and 'Social acceptance of GMO (2011-2015).' In a comparison between the media with different ideological goals, the Chosun Ilbo had a stronger new-technological inclination to GMO than the Hankyoreh in reporting topics and tones of arguments. As a result of checking the relation of the tones in reporting with the 'risk-benefit' of GMO, reports in negative tones underlined 'risk' while those in positive tones, 'benefit.' This study could suggest improvements of subject bias and unprofessionalism in the domestic science journalism, the barometer of public awareness of disputes over science and technology risk.

• Journal of the Korean Institute of Intelligent Systems
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• v.19 no.1
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• pp.34-39
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• 2009

As a subjective recognition effect, human's emotion has impulsive characteristic and it expresses intentions and needs unconsciously. These are pregnant with information of the context about the ubiquitous computing environment or intelligent robot systems users. Such indicators which can aware the user's emotion are facial image, voice signal, biological signal spectrum and so on. In this paper, we generate the each result of facial and voice emotion recognition by using facial image and voice for the increasing convenience and efficiency of the emotion recognition. Also, we extract the feature which is the best fit information based on image and sound to upgrade emotion recognition rate and implement Multi-Modal Emotion recognition system based on feature fusion. Eventually, we propose the possibility of the ubiquitous computing service reasoning method based on Bayesian Network and ubiquitous context scenario in the ubiquitous computing environment by using result of emotion recognition.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.6
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• pp.1355-1360
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• 2014

In this paper, we apply the learning of the mobile robot insect augmented reality Digilog Book. In the era of electronic, book written in paper space just have moved to virtual reality space. The virtual reality, constraints spatial and physical, in the real world, it is a technique that enables to experience indirectly situation not experienced directly as user immersive experience type interface. Applied to the learning robot Digilog Book that allows the fusion of paper analog and digital content, using the augmented reality technology, to experience various interactions. Apply critical elements moving, three-dimensional images and animation to enrich the learning, for easier block assembly, designed to grasp more easily rank order between the blocks. Anywhere at any time, is capable of learning of the robot in Digilog Book to be executed by the mobile phone in particular.

• Journal of the Korean Society of Costume
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• v.65 no.2
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• pp.105-124
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• 2015

This research was started to study how the design identity of an overseas fashion house was formed, changed and connected. For the purpose of the study, Saint Laurent House was selected as the subject of the study, because it began as a couture house and launched the $pr\hat{e}t-\grave{a}-porter$ for the first time among the designer brands, and also contributed to the development of modern women's fashion. Literature survey on related books and papers was performed to study the Saint Laurent House. Then, fashion collection photos of the house from 1962 SS to 2014 SS were collected to analyze and compare the features of the designs. The photos were collected from related books, fashion magazines and internet sites. The results are as follows: The features of Yves Saint Laurent's early designs were contemporarily sensational with their couture tradition. His representative designs including Le Smoking, Pea Coat, Loose Fit Blouse, Safari Look, Jumpsuit, Ethnic Look and Art Look became the signature looks of the Saint Laurent House. His designs expressed the liberation of sex, multi-cultural sensitivity and the fusion of art and fashion. His successor, chief designer Tom Ford designed with strong sensitivity of his own. He dealt with Yves Saint Laurent's design themes and signature looks in sensual as well as trendy and sophisticated way. Stefano Pilati showed the Parisienne chic and elegance. He re-made the legacies of Yves Saint Laurent with his own design style using new materials or cutting technique. Hedi Slimane reinterpreted the signature looks of the house with his rock' n roll mood for young, modern women while reflecting the spirit of Yves Saint Laurent's early stage. In conclusion, the design identity of Saint Laurent House is not just a fixed one. By the subsequent chief designers, the signature items and design spirit of Yves Saint Laurent have been succeeded, reintroduced or changed to be trendy and to reflect the designers' design sensitivity. All of these make and maintain the design identity of the fashion house.

• Structural Engineering and Mechanics
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• v.52 no.5
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• pp.889-901
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• 2014

Very long life fatigue tests were carried out on 16Mn steel base metal and its welded joint by using the ultrasonic fatigue testing technique. Specimen shapes (round and plate) were considered for both the base metal and welded joint. The results show that the specimens present different S-N curve characteristics in the region of $10^5-10^9$ cycles. The round specimens showed continuously decreasing tendency while plate specimens showed a steep decreasing step and an asymptotic horizontal one. The fatigue strength of round specimen was found higher than plate specimen. The fatigue strength of as-welded joint was 45.0% of the base material for butt joint and 40% for cruciform as-welded joint. It was found that fracture can still occur in butt joint beyond $5{\times}10^6$ cycles. The cruciform joint has a fatigue limit in the very long life fatigue regime ($10^7-10^9$ cycles). Fatigue strength of butt as-welded joint was much higher as compared to cruciform as-welded joint. Improvement in fatigue strength of welded joint was found due to UPT. The observation of fracture surface showed crack mainly initiated from welded toe at fusion areas or geometric discontinuity sites at the surface in butt joint and from welded toe in cruciform joint.