• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.30 no.12
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• pp.800-805
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• 2017

Randomly patterned and wet chemical etching processes were used to treat anti-glare of display cover glasses. The surface and optical properties of grain size and surface morphology controlled by randomly patterned etching and wet chemical solution etching were investigated. The surface morphology and roughness of the etched samples were examined using a spectrophotometer and a portable surface roughness (Ra) measuring instrument, respectively. The gloss caused by reflection from the glass surface was measured at $60^{\circ}$ using a gloss meter. The surface of the sample etched by the doctor-blade process was more uniform than that obtained from a screen pattern etching process at gel state etching process of the first step. The surface roughness obtained from the randomly patterned etching process depended greatly on the mesh size, which in turn affected the grain size and pattern formation. The surface morphology and gloss obtained by the etching process in the second step depended primarily on the mesh size of the gel state etching process of the first step. In our experimental range, the gloss increased on decreasing the grain size at a lower mesh size for the first step process and for longer reaction times for the second step process.

• Journal of information and communication convergence engineering
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• v.17 no.1
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• pp.84-90
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• 2019

Applications of unmanned aerial vehicles (UAVs) in the military environment have become popular because they require minimum human contribution and can avoid accidents during missions. UAVs are employed in various missions such as reconnaissance, observation, aggression, and protection. Consequently, counter-measures, known as anti-drone technologies, have been developed as well. In order to protect against threats from anti-drone technologies and enhance the survivability of UAVs, this study proposes an evasive measure. The proposed bio-inspired evasive maneuver of a UAV mimics a dragonfly's irregular flight. The unpredictable UAV movement is able to confuse enemies and avoid threats, thereby enhancing the UAV's survivability. The proposed system has been implemented on a commercial UAV platform (AR Drone 2.0) and tested in a real environment. The experiment results demonstrate that the proposed flight pattern has larger displacement values compared to a regular flight maneuver, thus making the UAV's position is difficult to predict.

• Journal of Oral Medicine and Pain
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• v.41 no.1
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• pp.16-20
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• 2016

Purpose: Oral lichen planus (OLP) is relatively common mucosal disease in clinical dentistry. OLP is intractable and regarded having malignant potential. Until now, there is some debate on how far OLP can be malignant, and which characteristics can be a risk factor for malignant transformation. Clinician need to know some differences between OLP and lesions similar to OLP to manage properly and suppose prognosis correctly. Therefore, the aim of this study was to divide clinical OLP into two groups and to compare the results of direct immunofluorescence (DIF) between two groups. Methods: This study was conducted on outpatients who visited at the department of Oral Medicine in Chonbuk National University Hospital from January 2007 to November 2015. Patients with DIF result were retrospectively reviewed. The selected patients were classified 'clinical typical of OLP' (CTO) or 'clinical compatible with OLP' (CCW) by modified World Health Organization diagnostic criteria of OLP and oral lichenoid lesion. Results: DIF were classified by deposition intensity or pattern of anti-human antibody and fibrinogen. The classification of fluorescence pattern in each specimen was graded as positive, possibly positive or negative. Conclusions: Both CTO and CCW had positive and possibly positive pattern. Prevalence of positive pattern was 68.8% in CTO and 52.6% in CCW and that of possibly positive pattern was 9.4% in CTO and 5.3% in CCW. Prevalence of negative was 21.8% in CTO and 42.1% in CCW.

• Journal of the Korea Institute of Military Science and Technology
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• v.9 no.3
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• pp.48-55
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• 2006

This paper describes the antenna based GPS anti-jamming technology called CRPA(Controlled Reception Pattern Antenna), which used $2{\times}2$ array elements. In this system, the main functions are the antenna complex weight control and the GPS digital I/Q VM(Vector Modulator). To update the VM's I/Q complex weights, the PC based DAC(Digital to Analog Converter) module was also used and the two analog output voltages were applied to the $2{\times}2$ array elements to synthesize the null pattern. In the study, we also simulated the $2{\times}2$ GPS array null patterns to compare the null depth with experimental results. The VM was also modified at the frequency of 1.575GHz for the GPS L1 and controlled by the PC based VM software.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2009.05a
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• pp.240-243
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• 2009

Recently, many researches on the development of super-hydrophobic and anti-reflective surfaces have been concentrated on the fabrication of nano-patterned products. The nano-patterned mold is a key to replicate nano-patterned products by mass production techniques such as injection molding and UV molding. The present paper proposes fabricating nano-patterned mold with cost-effective method. The nano-pattern molded was fabricated by electroforming the anodic aluminum oxide template without E-beam lithography. The final mold with nano-patterns showed the pores with the diameter of $100{\sim}120$ nm and the height of 150 nm was fabricated.

• Proceedings of the Korean Society Of Semiconductor Equipment Technology
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• 2005.09a
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• pp.147-150
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• 2005

We process a novel approach cal led combined nanoimprint and photolithography (CNP) to greatly simplify the fabrication in conventional nanoimprint lithography (NIL). In this study, a novel HMM with anti-sticking $SiO_2$ layer is introduced to improve the quality of transferred pattern. The surface property was investigated using contact angle measurement and spectrophotometer. Replicate pattern with CNP using HMM showed complete pattern transfer without defect.

• Korean Journal of Microbiology
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• v.47 no.2
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• pp.163-166
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• 2011

For reduction of side effects by anti-fungal agents, a less toxic anti-fungal substance or a synergistic substance with a new mechanism is needed. The anti-yeast substance (AYS) originated from Rahnella aquatilis strain AY2000 is like to be a heterogeneous protein. The AYS inhibited the growth of Candida albicans in culture broth, and AYS-treated cells were arrested in each phase during cell cycle. Among AYS-treated cells, the population of the cells belonging to sub-G1 phase was not increased during cell cycle. Therefore, AYS has rather yeaststatic than yeastcidal effect to C. albicans. Moreover, with combination of itraconazole or fluconazole, AYS had a synergistic anti-yeast activity against Saccharomyces cerevisiae based on the analysis of fractional inhibitory concentration index.

• The Journal of the Acoustical Society of Korea
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• v.19 no.2
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• pp.90-94
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• 2000

In this paper, we propose an efficient method of estimating a critical threshold which is used to reject unreliable patterns in a HMM based recognition system. The rejection methods based on the anti-models which are formulated as the statistical hypothesis determine whether or not to accept an input pattern by comparing the likelihood ratio of HMM and anti-models to a critical threshold. It is quite difficult to fix a threshold for the probability of a HMM because the range of such probabilities varies severely depending on the chosen class model. We estimate the critical threshold, which is very class-dependent, using the likelihood scores for the training database. In our experiments, we applied the proposed estimating method of the threshold to the HMM based 3D hand gesture recognition system. We found that this method can be used successfully for rejecting unreliable input gestures regardless of the types of anti-models.

• The Korea Journal of Herbology
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• v.27 no.4
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• pp.33-44
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• 2012

Objectives : There is a pressing need to determine the clinical and scientific validity of herbal therapies for animal model with atopic dermatitis since some differences in systemic cytokine polarization between in animal model and in patients with atopic dermatitis has been reported. New studies for tang, medicinal herb itself or effective ingradients of medicinal herb showing anti-atopic dermatitis effectiveness are reviewed in terms of cytokine regulation. Methods : Those herbal therapies used to treat atopic dermatitis in animal model were introduced and the expression pattern of cytokine and the activity of mast cell were compared in both animal model and patients with atopic dermatitis. Results : In case of atopic dermatitis in human, there is a biphasic pattern of cytokine expression in atopic dermatitis, with acute skin inflammation associated with a predominance of IL-4 and IL-13 expression from Th2 cells, and chronic inflammation associated with increased IL-5 from Th2-cells and IFN-${\gamma}$ from Th1-cells. However, a pattern of cytokine expression in animal model with atopic dermatitis is not matched well to the biphasic pattern of cytokine expression in patients with atopic dermatitis. In addition, a kind of cytokine is different by animal model with atopic dermatitis. These differences would make herbal medicines, showing their effectiveness on atopic dermatitis, difficult to apply to patients with atopic dermatitis. Conclusion : The pattern of local cytokine expression plays an important role in modulating tissue inflammation, and in atopic dermatitis this pattern depends on the acuity or duration of the skin lesion. Thus, in order to develop medicinal herb itself or effective ingradients of medicinal herb showing anti-atopic dermatitis effectiveness, biphasic pattern of cytokine expression should be considered in animal model with atopic dermatitis.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.413-413
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• 2014

In this paper, we present a fabrication method of functionalized gold nanostructures on flexible substrate that can be implemented for plasmonic sensing application. For biomolecular sensing, many researchers exploit unconventional lithography method like nanoimprint lithography (NIP), contact transfer lithography, soft lithography, colloidal transfer printing due to its usability and easy to functionalization. In particular, nanoimprint and contact transfer lithography need to have anti-adhesion layer for distinctive metallic properties on the flexible substrates. However, when metallic thin film was deposited on the anti-adhesion layer coated substrates, we discover much aggravation of the mold by repetitive use. Thus it would be impossible to get a high quality of metal nanostructure on the transferred substrate for developing flexible electronics based transfer printing. Here we demonstrate a method for nano-pillar mold and transfer the controllable nanoparticle array on the flexible substrates without an anti-adhesion layer. Also functionalization of gold was investigated by the different length of thiol applied for effectively localized surface plasmonic resonance sensing. First, a focused ion beam (FIB) and ICP-RIE are used to fabricate the nanoscale pillar array. Then gold metal layer is deposited onto the patterned nanostructure. The metallic 130 nm and 250 nm nanodisk pattern are transferred onto flexible polymer substrate by bi-layer functionalized contact imprinting which can be tunable surface energy interfaces. Different thiol reagents such as Thioglycolic acid (98%), 3-Mercaptopropionic acid (99%), 11-Mercaptoundecanoic acid (95%) and 16-Mercaptohexadecanoic acid (90%) are used. Overcoming the repeatedly usage of the anti-adhesion layer mold which has less uniformity and not washable interface, contact printing method using bi-layer gold array are not only expedient access to fabrication but also have distinctive properties including anti-adhesion layer free, functionalized bottom of the gold nano disk, repeatedly replicate the pattern on the flexible substrate. As a result we demonstrate the feasibility of flexible plasmonic sensing interface and anticipate that the method can be extended to variable application including the portable bio sensor via mass production of stable nanostructure array and other nanophotonic application.