• Convergence Security Journal
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• v.23 no.4
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• pp.3-15
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• 2023

As remote services and remote work become commonplace, the use of the Metaverse has grown. This allows transactions like real estate and finance in virtual Second Life. However, conducting economic activities in the Metaverse presents unique security challenges compared to the physical world and conventional cyberspace. To address these, the paper proposes solutions centered on authentication and privacy. It suggests improving data preprocessing based on Metaverse data's uniqueness and introduces a new authentication service using NFTs while adhering to W3C's DID framework. The system is implemented using Hyperledger Indy blockchain, and its success is confirmed through implementation analysis.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.39C no.2
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• pp.184-190
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• 2014

Until now ship communication micro serial network communication method is designed for the communication between the controller and the RS-422 communication on the international standard ISO 1993, but gradually progresses NMEA 2000 standardized fast Ethernet-based communications environments expected to be replaced. In addition, the ship's main instrumentation equipment versatility with ease gradually to control devices by monitoring and controlling are. Wind anemometer, ship mast end, where the highest wind farms typically install a separate console boxes, data loggers, indicators was required in order to manage them, to maintain them, to go through the procedures and cumbersome data update firmware were Therefore, in this paper, using the PC network, ultrasonic wind speed data processing system for implementing functional was expressed as a function of the technology elements, NMEA 2000 standard certified in separate operating console without the features of the data loggers, indicators, implementation by ultrasonic wind data processing system was implemented to minimize the maintenance cost of the operating system.

• International Journal of Highway Engineering
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• v.13 no.3
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• pp.65-73
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• 2011

Recently, researches to introduce the performance warranty contract are in progress for quality improvement of road pavements. The performance warranty contract is a type of contract in which contractors guarantee to maintain certain level of performance during a period from completion of construction. The contract use in Europe and the U.S is being increased because it has been known to contribute to improvement of structure quality, reduction of life cycle cost, development of construction techniques, and etc. The research on performance indicators, threshold values, and warranty durations is essential to effectively introduce the contract in Korea. In this study, literatures on the performance warranty contract for concrete pavements of the Minnesota, Indiana, and Florida of the U.S. were reviewed. Major distresses influencing the pavement performance were investigated and analyzed in the jointed concrete pavement sections of 21 Korean expressway routes to be compared to the performance indicators, threshold values, and warranty durations of the states. More accurate comparison is expected by investigation in planned sections for a long time.

• Fashion & Textile Research Journal
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• v.14 no.5
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• pp.749-757
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• 2012

The purpose of this study is to consider the characteristics of Latin American style expressed in modern fashion. Latin American fashion has been overlooked the influences, scope and diversity of dress within this world culture region. So, this study aim to unravel the history and significance of Latin American fashion. As for the research methodology, to classify types of the Latin American fashion style theoretical study and content analysis for Vogue magazine has been undertaken. In this study, the term of Latin American fashion style refers to the dress of common characteristics involving Latin American culture. To inquire into the characteristics of the types, various cases has been searched through books, internet, and designer's collections. The results of this study can be summarized as followings. The major types of Latin American fashion style are Indio-ethnic style, tropical-exotic style, and latin-romantic style. First, Indio-ethnic style has been involving traditional costumes and patterns which are originated in ancient Mexico and Peru. Second, tropical-exotic style has been involving bright color, tropical fruit and African flower pattern, various textures, and relaxed silhouette which are inspired by free and easy culture in Brazil and the Caribbean. Third, latin-romantic style has been involving the mix of Latin American tradition and romantic detail such as see-through material, lace, ruffle, spanish flower motif. In conclusion, Latin American style on contemporary fashion is based on interest to cannibalize folk theme, technique, icons and exotic others.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2017.04a
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• pp.64-64
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• 2017

노지 고추 수확작업은 7~9월에 걸쳐 5~6회 수행되며 가장 더운 한 여름의 태양볕에 노출되어 장시간 수확작업을 하며 노지채소 및 고추 수확작업시 자외선 과다 노출되어 악성흑생종, 광선각화증, 편평세포 암 및 각종 피부암발생의 원인되기 때문에 적절한 해가림 장치의 설계가 필요하다. 해를 가려주는 장치에 사용되는 재질로는 우산 및 양산에 널리 사용되어지는 섬유로 폴리에스테르를 선정하였으며 두께로 우산의 재질로 많이 사용되는 75 denier을 채택하였다. 코팅의 종류로는 Foam, Milky, Silver, 폴리우레탄을 채택하여 섬유의 코팅 종류에 따른 차단 효과를 실험하였다. 실험 방법으로서는 KS K 0850 텍스타일의 자외선 차단율 및 차단지수 시험방법에 의거 하여 실험하였다. 자외선 UV-A(365n/m), UV-B(315n/m) 측정장치는 자외선 센서, UV램프, 인디케이터로 구성된 측정기를 이용하였으며 각 재료별 5회 반복 실시하여 평균치를 산출 하였다. UV-A(365n/m) 측정값으로는 FOAM, MILKY코팅이 된 섬유재질이 KS의 우산 및 양산품질표시기준에 부합하여 해가림 장치에 사용이 적절하였으며 UV-B(315n/m) 파장 차단율 측정값으로는 KS의 우산 및 양산품질표시기준에 모두 부합되었다. 또한 해가림 장치는 태양고도에 따라 각도를 조절 가능한 형태로 설계하였으며 직사광선이 가장 강한 시간대인 10시부터 12시를 기준하여 틸팅의 최대 각도는 20도로 개발하였다. 또한 바람에 의한 날림현상을 방지하고 통풍효과를 높이기 위해서 해가림 장치의 섬유를 2중 구조로 설계하여 바람의 순환이 되게하였다.

• Textile Coloration and Finishing
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• v.21 no.3
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• pp.10-18
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• 2009

Dyeing process of the natural indigo powder onto ramie and silk fabrics was investigated by using glucose and calcium hydroxide as a reducing system. Effect of reduction and dyeing conditions such as temperature and time of reduction/dyeing, and concentrations of glucose and calcium hydroxide on the dyeing process were explored. Indigo powder was obtained by drying the conventional niram paste in an oven at $50^{\circ}C$. Color strength of the dyed fabrics was evaluated by K/S value measured at the wavelength of maximum absorption(${\lamda}$max). Munsell color coordinates(H V/C) were used to compare fabric colors of ramie and silk. Ramie fabric showed purple-blue color for all the temperature and time. On the contrary, silk fabric showed wide range of color including brown, brown-green, green at the different temperature. With the increase of K/S value, the coordinate of value(lightness) decreased for both of ramie and silk fabrics. The coordinate of hue(shade) changed drastically with the increase of K/S value for silk fabric, compared with that of ramie fabric which showed nearly constant value at the whole range of K/S value. Optimum concentrations of calcium hydroxide were for 6 g/L for ramie and 4 g/L for silk at $60^{\circ}C$ and 50 min. K/S value increased with the indigo concentration. Maximum K/S value was shown at $10{\sim}12$ g/L of glucose concentration. For both of ramie and silk fabrics, the colorfastness of washing and light was lower than that of rubbing. All the colorfastness values were improved with the increase of color strength.

• Textile Coloration and Finishing
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• v.22 no.2
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• pp.101-109
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• 2010

The objective of this study is to investigate the characteristics of natural indigo dyeing of cotton fabric. Reduction and dyeing were carried out by one-step process using an infrared dyeing machine at the liquor ratio of 1:100, and subsequently oxidation and washing in water were followed. Dye uptake was increased with the increase of indigo concentration. Over the full range of dyeing tests, the dyeing condition was optimized to $40^{\circ}C$ for 40min. For most of dye concentrations, the cotton fabrics showed mainly PB color. Maximum K/S value was shown at 4g/L of sodium hydrosulfite concentration and the color strength increased with the increase of dye concentration. Value(lightness) decreased with the increase of dye uptake irrespective of mercerization or reduction method, while the mercerized cotton showed two times higher dye uptake than the untreated cotton. Whereas hue of the untreated cotton showed large decrease of P character(5.6~3.5 PB) with the increase of dye uptake, that of the mercerized cotton increased P character(4.7~5.5 PB). Irrespective of mercerization, value and chroma decreased with the increased of dye uptake. In addition, the untreated showed lower chroma than the mercerized cotton. In the case of traditional reduction, hue of the untreated cotton was changed very little with the increase of dye uptake. For hydrosulfite reduction, P character decreased with the increase of dye uptake. The difference of hue value was small with the change of reduction method(hydrosulfite reduction or traditional fermentation). Color character was not influenced by the changed maximum absorption wavelength. Washing fastness showed 4~4/5 shade change rating without any staining. And dry rubbing fastness was good at low color strength. The bacterial reduction ratios of dyed cotton fabric were also increased.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.48 no.3
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• pp.57-65
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• 2016

Indigo (Polygonum tinctorium L.) is a typical blue dye which had been used from ancient times. This study was going to shade the complicated traditional methods extracting indigo dye by the fermentation and producing as adsorbate on calcium hydroxide, which says so called as the 'Indigo lime'. Accordingly we were going to make indigo through the hydrolysis of the hot water extractives of indigo leaves simply. During hot-water extraction, ${\beta}$-glucosidase which required hydrolysis of the linkage between indigo and glucose was not activated. To achieve this goal, indican was acid-hydrolyzed to glucose and indigo. The acetic acid, citric acid, hydrochloric acid, and sulfuric acid were used for the hydrolysis of hot water extractives. The hydrolysis conditions of extractives performed in water bath at $80^{\circ}C$ for 120 minutes and in an autoclave for 120 minutes. In the acid hydrolysis of extracted indican by hot water, the indican yields of acetic acid and hydrochloric acid hydrolysis were higher than sulfuric acid in water bath. Also, the indican yield of hydrochloric acid hydrolysis was better than sulfuric acid in autoclave. The hot water extracted indican was confirmed by HPLC analysis and its structure was confirmed by UV-Vis and FT-IR spectroscopy, compared with isolated indigo and commercial synthesized indigo. This improved extraction and hydrolysis methods can be replace the traditional indigo making method.

• Proceedings of the Korea Water Resources Association Conference
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• 2009.05a
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• pp.1380-1383
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• 2009

수질오염총량관리제도(TMDL)는 유역의 수질 회복 및 관리를 위해 우리나라를 비롯해 미국의 여러 주에서 수립되어 적용되고 있다. 현재 미국에서는 유역 관리를 위한 TMDL의 기준설정에 있어 오염부하지속곡선(LDC)의 활용이 급격히 증가되고 있다. 그러나 기존의 LDC 방법은 사용자로 하여금 충분한 교육이 필요하고 LDC 생성을 위한 데이터 구축이 수동적으로 이루어지고 있다. 이러한 문제를 해결하기 위해 최근 Web GIS 기반의 LDC 시스템이 개발되어 활용되고 있다. 웹기반의 LDC 시스템은 미국 지질 조사국(USGS)이나 한국 환경부(MOE) 서버 등을 통해 구축된 자료를 이용하여 오염부하지속곡선을 생성하기까지의 모든 과정이 자동으로 처리되어 기존 수작업에 의한 방법의 단점을 보완하고 있다. 그리하여 본 연구에서는 우리나라 수질오염 총량 관리제도 단위유역인 낙본A와 금본C, 그리고 미국 인디애나 주의 Yellow River와 펜실베이니아 주의 Borkenstraw Creek 유역을 대상으로 웹기반 LDC 시스템을 이용하여 유역의 특성을 분석하였다. 본 연구에서 사용된 유량 및 수질 자료는 본 시스템에서 연계된 환경부 서버와 USGS 서버를 통해 구축하였다. 분석 결과 낙본 A 단위유역의 BOD 오염부하량과 농도가 대체적으로 목표수질 기준을 만족하는 것으로 나타났으나 전반적으로 유량이 적을 때 다소 목표수질을 초과하고 있는 나타나, 적합한 수질관리 대책이 필요한 것으로 분석되었다. 금본 C 단위유역의 경우 대부분 BOD 배출부하량이 할당 부하량보다 낮게 나타나는 것을 알 수 있고, 목표수질 농도에 비해 배출되는 BOD 농도 또한 대체적으로 낮은 것을 알 수 있다. 또한 Yellow River 유역의 경우는 유량이 많을 때 배출되는 수질농도가 목표수질을 초과하는 것으로 보아 강우시 배출되는 오염물에 대한 대책이 요구되고, Borkenstraw Creek 유역의 경우 유량이 적을 때를 제외하고 대부분 구간에서 배출부하량이 할당부하량을 초과하여 이에 대한 적합한 수질관리가 필요할 것으로 분석되었다. 본 연구의 결과에서 나타난 바와 같이 웹기반 LDC 시스템을 통해 수질오염총량관리제도 단위유역에 대한 수질 평가 및 특성 분석이 용이하며 수질 회복을 위한 근본적인 해결방법을 제시할 수 있을 것으로 판단된다.

• Proceedings of the Korea Water Resources Association Conference
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• 2009.05a
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• pp.1417-1421
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• 2009

최근 들어 유역의 정확한 수문현상을 파악하기 위하여 유역의 유출량 자료를 직접 유출과 기저유출로 분리한 후 수문 모형의 직접유출 및 기저유출의 수문컴포넌트 검증에 활용하는 연구가 많이 이루어지고 있다. 미국 국립지리국 (USGS) 에서 개발한 HYSEP 모형이 지난 수 년 동안 유출 컴포넌트 분리에 널리 이용되어 오고 있다. 그러나 USGS 기반의 HYSEP의 경우 능숙한 컴퓨터 사용자가 아닌 비전문가들이 HYSEP을 운영하기에는 여러 가지 많은 제한점이 있어 왔다. 그리하여 본 연구에서는 고해상도 위성영상 Google Map 기반의 기저유출분리 프로그램인 Web-based HYSEP 인터페이스를 개발하였다. 이 시스템에는 HYSEP에서 제공하는 3가지 방법인 Fixed Interval / Sliding Interval / Local Minimum 방법이 제공되고 있다. 본 연구에서 개발된 Google Map 기반의 HYSEP 시스템은 USGS 유량 관측지점들에 대해 XML 데이터 포맷으로 DB를 구축하여 Google Map 과 연계하였으며 이를 통해 사용자가 원하는 관측소의 실시간 유량자료를 다운로드 할 수 있도록 개발되어졌다. Google Map 기반의 HYSEP 기저유출 분리 시스템(http://www.EnvSys.co.kr/${\sim}$hysep)은 Perl/CGI 및 자바스크립트, Google Map script 등을 이용하여 개발되었다. 현재 개발된 Google Map 기반의 USGS HYSEP 시스템은 한 곳의 유량관측지점에 대해서 총 3가지 기저유출 모듈을 적용하여 결과를 제공하고 있으며, 그 결과를 테이블이나 그래프 형태로 제공하도록 되어 있다. 본 연구에서는 Google Map 기반의 USGS HYSEP 시스템을 이용하여 미국 인디애나 주의 Little Eagle Creek 유역의 유량자료와 Fixed Interval / Sliding Interval / Local Minimum 방법을 이용하여 기저유출을 분리하였으며, 기존에 널리 활용되는 기저유출 분리 프로그램인 Web 기반의 WHAT 시스템 (http://www.EnvSys.co.k.r/~what) 산정 기저유출량과 비교분석하였다. 분석결과 HYSEP 예측 기저유출치가 전반적으로 WHAT 예측치보다 크게 산정되었다. WHAT 시스템과 본 연구에서 개발한 Web 기반의 HYSEP 일단위 기저유출량을 비교해 본 결과 $R^{2}$가 0.56, EI는 0.52로 어느 정도 비슷한 경향을 나타냈으나, 유역의 특성을 반영하는 WHAT 시스템과는 달리 주어진 유량자료만을 이용하여 기저유출을 분리하는 Web 기반의 HYSEP 기저유출 분리모듈을 개선할 필요가 있는 것으로 판단된다.