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Interaction Between Surface Plasmon Resonance and Inter-band Transition in Gold Thin Film (금 박막에서 표면 플라즈몬 공명과 국소적 밴드 간 천이의 상호작용)

  • Kang, Daekyung;Kumar, Marredi Bharath;Adeshina, Mohammad Awwal;Choi, Bongjun;Park, Jonghoo
    • Journal of Sensor Science and Technology
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    • v.28 no.4
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    • pp.262-265
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    • 2019
  • The effect of inter-band transition on surface plasmon resonance in gold thin film was investigated. We induced localized inter-band transition in the film by using incident light on its surface from a green laser (532 nm) source, and the surface plasmon resonance for inter-band transition was investigated at different wavelengths. It was determined that the reflectivity of blue light (450 nm) was significantly reduced in the region where the green laser was incident. We demonstrated that this decrease is mainly due to the coupling between the blue light and the surface plasmon resonance of excited electrons in higher energy states, based on experimental results for the incident and polarization angle-dependent reflectivity of the blue light.

Correlation between Volume and Pressure of Dichloromethane using Equation of State (상태방정식을 이용한 디클로로메탄의 부피와 압력간 상관관계 연구)

  • Kwon, Woong;Kim, Jiyun;Lee, Kwonyun;Jeong, Euigyung
    • Textile Coloration and Finishing
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    • v.33 no.3
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    • pp.141-146
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    • 2021
  • Supercritical fluid has excellent dissolving power for various materials based on low viscosity and high diffusion coefficient and is used as solvents in various chemical processes. However, its industrial application can be very tricky because the design, especially the size of the supercritical apparatus, should be carefully chosen to optimize the cost and the production of supercritical fluidic state. And the first step of the supercritical fluid apparatus design is to choose the appropriate size of the reactor vessel to produce supercritical fluid above its critical pressure and temperature. Therefore, this study aims to analyze thermodynamic behaviors of dichloromethane based on ideal gas, van der Waals, Redlich-Kwong, Soave-Redlich-Kwong, and Peng-Robinson equations of state. The correlation between the volume and pressure of dichloromethane at 200℃ was revealed and it can be used to design the optimized size of the supercritical apparatus for industrial production.

Color Strength and Fastness of Pigment Ink with Various Binder Monomer Compositions (바인더의 공중합체 조성에 따른 안료잉크의 발색성 및 견뢰도 연구)

  • Kwon, Woong;Lee, Minkyu;Jeong, Euigyung;Bae, Jin-Seok
    • Textile Coloration and Finishing
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    • v.30 no.4
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    • pp.256-263
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    • 2018
  • The binder polymers for digital textile printing(DTP) pigment inks were prepared using miniemulsion polymerization with various monomer compositions to study effects of monomer compositions on particle size distribution, average molecular weight, Tg, and color strength and rubbing fastness of the dyed fabrics with the prepared binder based pigment ink. The monomers used were MMA(Methyl methacrylate), BA(Butyl acrylate), MAA(Methacrylic acid), NMA(N-methylol acrylamide), NEA(N-ethylol acrylamide) and the ratios of the monomers were changed. The particle size was the smallest with 136nm when the MMA to BA weight ratio was 4:16 and the largest with 290nm when the MMA, BA, MAA, NEA ratio was 2.5:17:0.25:0.25. However, the glass transition temperature was lowest with $-41.90^{\circ}C$ and the color strength and rubbing fastness of the resulting sample were the best when the MMA, BA, MAA, NEA ratio was used. This suggested that the introduction of the NEA monomer to the binder polymer for the pigment ink could be an efficient way to enhance the rubbing fastness of the DTP pigment inks present.

Effect of Polytriazolesulfone Addition on Fracture Toughness of DGEBA Epoxy Resin (DGEBA에 대한 폴리트리아졸술폰의 강인화 효과 연구)

  • Kwon, Woong;Lee, Minkyu;Han, Minwoo;Jeong, Euigyung
    • Textile Coloration and Finishing
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    • v.31 no.2
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    • pp.118-126
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    • 2019
  • This study aims to investigate the effect of polytriazolesulfone(PTS) addition on fracture toughness of diglycidyl ether of bisphenol A(DGEBA) and 4,4'-diaminodiphenylsulfone(DDS). Various amounts of PTS were added to DGEBA/4,4'-DDS in diazide and dialkyne monomer forms and polymerized during the epoxy curing process. Fracture toughness(K1C), tensile properties and thermal stability of the PTS added epoxy resin were evaluated and compared with those of PES, the conventional high Tg toughening agent, added epoxy resin. Fracture toughness of the PTS added epoxy resin was dramatically improved up to 133%, as the amount of PTS added increased, whereas that of the PES added epoxy resin was improved by only 67%. The tensile strength of PTS added DGEBA/4,4'-DDS was similar to the epoxy resin without PTS and tensile modulus was improved by 20%. And thermal stability of the PTS added epoxy resin was improved up to 14%. Therefore, PTS addition to DGEBA/4,4'-DDS, as a toughening agent, is very effective way to improve its fracture toughness without any lowering in other properties.

Dyeing of High Strength and High Molecular Weight Polyethylene Fiber Using Super Hydrophobic Red Fluorescence Dyes (고강도/고분자량 폴리에틸렌 섬유의 적색 초소수성 형광염료 염색)

  • Kim, Taegun;Lee, Junheon;Park, Jihoon;Kim, Taekyeong
    • Textile Coloration and Finishing
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    • v.30 no.4
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    • pp.237-244
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    • 2018
  • Three super hydrophobic red fluorescence dyes were selected to dye high molecular weight polyethylene fiber. Their absorbance and emission spectra were obtained and Stokes' shift was measured. Fluorescence emission strength of the dyes on the fiber was investigated and therefore Fluoro Red 3 was determined as the best one among those three dyes in this experiment. Dyeing properties and fluorescence intensities were investigated using the Fluoro Red 3 on high molecular weight polyethylene fiber at various dyeing conditions. The optimum concentration of a dispersing agent was appeared at 10wt% in aqueous solution. The best dyeing was obtained at $125^{\circ}C$ for 1 hour. The color fastnesses to the washing and rubbing were as high as ratings 4~5, however, the fastness to light was exhibited ratings 2~3.

Preparation and Evaluation of Self-cleaning Fabrics using Photocatalyst and Superhydrophobic Finishing (광촉매와 초발수 처리를 이용한 셀프클리닝 섬유의 제조 및 평가)

  • Jeong, Euigyung;Woo, Heejoo;Cho, Seungbin;Bae, Jin-Seok
    • Textile Coloration and Finishing
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    • v.30 no.4
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    • pp.288-293
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    • 2018
  • This study reported the dual functional self-cleaning PET fabrics prepared from $TiO_2$ and hexadecyltrimethoxysilane treatment, which have photodegradation and superhydrophobicity on the fabric surface. Phodegradation and superhydrophobicity of the resulting fabric were compared with $TiO_2$ or silane treated fabrics. The dual functional self-cleaning PET fabric showed less photodegradation than the $TiO_2$ treated fabric. However, the dual functional self-cleaning fabrics showed superior superhydrophobicity to silane treated fabric with increased water contact angle and significantly decreased roll-off angle. This suggested that the dual functional PET fabric has a great potential to be the commercialized self-cleaning fabric because it is repellent to soil or dust and even if soil or dust is adsorbed on the fabric surface, it can be removed by water rolling off on the surface or photodegradation by the photocatalyst.

Bozola Flap for Oral Cavity Reconstruction in Patients with Tongue Cancer (Bozola Flap을 이용한 설암 환자의 구강 재건술)

  • Kwak, Ji Hye;Lee, Gil Joon;Sohn, Jin Ho;Ahn, Dongbin
    • Korean Journal of Otorhinolaryngology-Head and Neck Surgery
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    • v.61 no.11
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    • pp.605-610
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    • 2018
  • Background and Objectives The purpose of the present study was to evaluate the usefulness of a posterior-based buccinator myomucosal flap (the Bozola flap) for the reconstruction of oral cavity defects after tongue cancer resection. Subjects and Method Fifteen patients who underwent from 2014 to 2016 reconstruction of the oral cavity with a Bozola flap after surgical management of tongue cancer were enrolled in the study. Patient characteristics, surgical outcomes, and complications associated with the Bozola flap were evaluated. Results The flap was successfully harvested and transferred in all patients. The mean flap harvesting time was 25.3 min. The donor site was closed primarily in 14 patients, and a buccal fat pad flap was used in one patient. Although partial necrosis of the flap occurred in two patients, no other major complications were noted. Conclusion The results of this study demonstrate that the Bozola flap is a good option for reconstruction of moderate sized oral cavity defects in tongue cancer patients.

Investigation on Rubbing Fastness of Pigment Ink with Polymer Binders having Various Comonomer Compositions (바인더 단량체 조성 변화에 따른 안료 잉크의 마찰견뢰도 연구)

  • Han, Minwoo;Kwon, Woong;Jeong, Euigyung;Bae, Jin-Seok
    • Textile Coloration and Finishing
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    • v.31 no.2
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    • pp.77-87
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    • 2019
  • To improve rubbing fastness of the printed fabrics, the binder polymers for Digital Textile Printing(DTP) pigment inks were synthesized with miniemulsion polymerization using various acrylic monomers, which are MMA(Methyl methacrylate), BA(Butyl acrylate), and Self-crosslinking monomers, such as NEA(N-Ethylol acrylamide) and MAA (Methacrylic acid). The acrylic monomer compositions were varied when synthesizing the binder polymers and their particle size distributions, average molecular weights, and Tgs were investigated. The prepared binder polymers were applied to prepare Cyan, Black, Yellow and Magenta pigment ink for DTP and the prepared inks were used to dye cotton fabrics. Then, color strength, and rubbing fastness were also investigated to study the effect of the comonomer compositions of the binder polymer on the color strength and rubbing fastness of the resulting pigment inks.

Sequence based Synchronization for Multi Drone Operation Simulation (다중 드론 운용 시뮬레이션을 위한 순서 기반 동기화 기법)

  • Kim, Deok Yeop;Seo, Kang Bok;Lee, Gwoncheol;Lee, Woo Jin
    • Proceedings of the Korean Society of Computer Information Conference
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    • 2019.07a
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    • pp.1-4
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    • 2019
  • 드론은 여러 센서를 사용할 수 있고 자율적으로 비행 가능하다는 이점 때문에 다양한 분야에 활용할 수 있다. 그러나 단일 드론으로는 수행할 수 있는 작업이나 미션이 제한적이기 때문에 최근에는 다중 드론을 활용한 군집 비행 기술 연구가 활발하게 이루어지고 있다. 드론은 테스트를 통해 동작 검증이 이루어지는데 테스트 비용이 크고 파손의 위험이 있기 때문에 시뮬레이션을 이용한 사전 검증이 먼저 이루어진다. 그런데 다중 드론을 이용한 군집 비행 시뮬레이션의 경우 드론들이 밀집해 있기 때문에 시뮬레이션 중 드론의 충돌사고가 발생할 수 있다. 동기화가 제대로 이루어지지 않은 시뮬레이션은 각 드론 소프트웨어의 정확한 동작을 보장할 수 없기 때문이다. 이러한 문제를 해결하기 위해서 본 논문에서는 순서 기반의 동기화 기법을 제안한다. 제안하는 기법은 기존 동기화 기법과는 달리 순서 기반의 동기화로 시뮬레이션 오버헤드를 줄이며 다중 드론의 군집 비행 시뮬레이션에서 예상하지 못한 드론의 동작을 최소화 할 수 있다.

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Farm Damage Prevention System Using Thermal imaging Camera and Deep Learning (열화상 카메라와 딥러닝을 이용한 농가피해방지 시스템)

  • Shin, Seung-min;Lee, Sang-hoon;Choi, Hyo-sun;Kim, Seung-hoo;Lee, Cherl-hee
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2019.05a
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    • pp.306-309
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    • 2019
  • The damage to farms due to wild animals such as wild boars and elks increases every year, but, in the current system, the catchers from government hunt animals by using guns at night as making an effort to detect wild animals personally by using flashlights. This is very time-inefficient and immediate follow-up action on being damaged is not possible. In this paper, we introduce a system which can detect and recognize the wild animals or the people with high accuracy using thermal imaging camera and infrared camera in company with deep learning technology, so that could kick out or catch the wild animals more quickly than current system.

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