• 한국환경농학회지
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• 제30권4호
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• pp.414-418
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• 2011

우리나라에서 주로 사용되고 있는 흑색 비닐멀칭과 신개발된 적색 비닐멀칭의 표면 반사광 특성을 분석하고 참외와 토마토에 대한 영향을 구명하여 작물생산에 대한 적용 가능성을 검토하였다. 적색 비닐멀칭의 표면에서 반사된 적색광과 초적색광의 일일 누적 강도는 흑색 비닐멀칭보다 2.6배 강했다. 적색광과 초적색광 반사광의 강도는 적색 비닐멀칭의 표면 높이 30 cm에서 가장 강하였다. 일중 태양광 강도가 강한 오후 1시 20분의 흑색 비닐멀칭의 Red/F-Red는 1.14, 적색 비닐멀칭은 0.93, 태양광은 1.16으로 적색 비닐멀칭이 흑색 비닐멀칭보다 초적색광 강도가 높았다. 적색 비닐멀칭의 Red/F-Red는 표면 높이 30 cm에서 가장 낮았으며 표면높이가 높아질수록 초적색광 강도가 감소하여 Red/F-Red는 증가하였다. 적색 비닐멀칭 반사광의 Red/F-Red는 정오부터 오후 4시경까지는 흑색 비닐멀칭보다 낮게 경과하였다. 흑색 비닐멀칭 처리구보다 적색 비닐멀칭 처리구의 참외 과실의 무게가 증가하여 수량이 증가하였고 당도가 높았다. 토마토의 과실 무게와 당도도 적색 비닐멀칭 처리가 흑색 비닐멀칭 처리구보다 높았다. 지중온도는 적색 비닐멀칭 처리가 흑색 비닐멀칭 처리보다 다소 낮은 경향이었다. 따라서 적색 비닐멀칭으로 토양을 피복하면 작물생산에 적색광과 초적색광을 더 많이 이용할 수 있을 것으로 판단된다.

• 대한원격탐사학회지
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• 제37권5_1호
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• pp.959-974
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• 2021

Forel-Ule Index (FUI)는 자연에 존재하는 담수 및 해수의 색을 남색부터 고동색까지 21 가지의 등급으로 구분하는 지표이다. FUI는 여러 선행연구에서 수계의 부영양화 지수, 수질인자, 광 특성 등과 연관 지어 분석되었으며, 여러 수질인자의 광학적 정보를 동시에 가지고 있는 새로운 수질 지표로써의 가능성이 제시되었다. 본 연구에서는 500 m의 높은 공간해상도를 가지는 정지궤도 해양위성해색탑재체(Geostationary Ocean Color Imager; GOCI) 관측 자료와 Random Forest (RF) 기계학습 기법을 활용하여 Ocean Colour-Climate Change Initiative(OC-CCI) 기반의 4 km FUI 자료를 공간 상세화 시켰다. 이를 활용하여 우리나라 연안 해역에 대한 수질인자와의 상관관계와 주요 해역에 대한 FUI의 공간적 분포 및 계절별 특성 변화를 분석하였다. 검증 결과 RF 기법으로 추정한 RF FUI는 결정계수(R²)=0.81, 평균 제곱근 오차(Root Mean Square Error; RMSE)=0.7784로, Pitarch의 OC-CCI FUI 알고리즘을 적용하여 계산한 GOCI FUI 추정 정확도(R²=0.72, RMSE=0.9708) 대비 향상된 결과를 보였다. RF FUI는 총 질소(Total Nitrogen), 총 인(Total Phosphorus), 클로로필-a(Chlorophyll-a), 총 부유물질(Total Suspended Solids), 투명도(Secchi Disk Depth)를 포함하는 5가지 수질인자와 각각 0.87, 0.88, 0.97, 0.65, -0.98의 상관계수로 강한 상관성을 보였다. 산출된 FUI의 시간적 패턴 역시 여러 수질인자와의 물리적 관계를 반영하며 유의미한 계절적 패턴의 변화를 보였다. 본 연구의 결과로 한반도 연안 수질 관리에서 고해상도 FUI의 활용 가능성을 제시하였다.

• 한국양봉학회지
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• 제34권2호
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• pp.107-115
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• 2019

Bumblebees have apposition compound eyes (one on either side of the head) of about 6,000 ommatidia and three small single-lens ocelli on the frons of their head capsule. The surface of the eye is smooth and interommatidial hairs, as in the honeybee, are not developed. Each ommatidium (approx. 26 ㎛ in diameter) is capped by a hexagonal facet and contains in its centre a 3 ㎛ wide, columnar light-perceiving structure known as the rhabdom. Rhabdoms consist of thousands of regularly aligned, fingerlike microvilli, which in their membranes contain the photopigment molecules. Axons from each ommatidium transmit the information of their photic environment to the visual centres of the brain, where behavioural reactions may be initiated. Since bumblebee eyes possess three classes of spectrally different sensitivity peaks in a ratio of 1:1:6 (UV= 353 nm, blue= 430 nm and green=548 nm) per ommatidium, they use colour vision to find and select flower types that yield pollen and nectar. Ommatidial acceptance angles of at least 3° are used by the bumblebees to discriminate between different flower shapes and sizes, but their ability to detect polarized light appears to be used only for navigational purposes. A flicker fusion frequency of around 110Hz helps the fast flying bumblebee to avoid obstacles. The small ocelli are strongly sensitive to ultraviolet radiation and green wavelengths and appear to act as sensors for light levels akin to a photometer. Unlike the bumblebee's compound eyes, the ocelli would, however, be incapable of forming a useful image.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
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• pp.773-775
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• 2004

For high end, large area displays, all current LC modes require some degree of optical compensation to improve the front of screen viewing experience. Currently most optical films are laminated to the outside of the LCD cell, between the glass and polariser. In this paper we wish to show how it is possible to integrate the compensating optical film within a VA mode LCD cell. The paper will describe the process of making the biaxial film through the process of in-situ photopolymerisation of an aligned film of reactive mesogens in the cholesteric phase using polarised UV light. The film can be made on the colour filter array side of the LCD panel. In addition the process of fabricating a VA mode LCD containing this film will be described and the performance of this module will be presented

• 한국염색가공학회:학술대회논문집
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• 한국염색가공학회 2011년도 제44차 학술발표회
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• pp.31-31
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• 2011

Lanasol dyes containing ${\alpha}$-bromoacrylamide or ${\alpha},{\beta}$-dibromopropionylamide group are used for wool dyeing. They are normally applied to wool under pH 4.5 to 6.5 at $100^{\circ}C$. Although wool fabric can be dyed to obtain deep colour, high light and wet fastness, the dyeing processes need long dyeing time at high temperature, with salt addition, which inevitably causes environmental problems. Grafting is a modification method for textile where monomers are covalently bonded onto the polymer chain. It can be initiated by ozone, ${\gamma}$ rays, electron beams, plasma, corona discharge and UV irradiation. Coloration by UV-induced photografting exhibits several advantages such as fast reaction rate, energy saving, simple equipment, easy exploitation and environmentally friendliness. Also it requires much lower energy compared to the conventional dyeing and less damage to the substrate. In this study, a direct sequential UV-induced photografting onto wool fabrics was discussed. To understand the graft polymerization mechanism further, several characterization methods were used. Moreover, the effects of several principal factors on the graft photopolymerization were investigated. Furthermore, the colorfastness results were compared with conventional dyeing methods.

• 한국잠사곤충학회지
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• 제40권1호
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• pp.78-85
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• 1998

Colorants were prepared by extraction of natural indigo which was harvested just in the blooming season(in the late of July). 100 g of fresh leaves soaking in 1 ιwater was kept at 3$0^{\circ}C$, 30 hours. A solution of 3g/l calcium hydroxide was added into it to precipitate dye substance and it was freezing-dried into powder form. The fermentation and dyeing conditions were investigated. The results obtained are summarized as follows; K/S value of dyed silk fabrics of fermentation conditions was higher at 95$^{\circ}C$ for 20 min. than at 4$0^{\circ}C$ for 20 hours. Furthermore, K/S value of dyed silk fabric was raised by the addition of 5g/l of glucose and 5g/l of NaOH. K/S value of dyed silk fabric was raised by the addition of 5g/l of glucose and 5g/l of NaOH. K/S value increased as extending of dyeing time when dyed till 2 hours at 3$0^{\circ}C$. K/S value decreased in order of 3$0^{\circ}C$, 4$0^{\circ}C$ and 5$0^{\circ}C$, at the various dyeing temperatures and dyeing concentrations, and colour fastness ranged from 4 to 5 grade in terms of washing, perspiration and light fastness.

• The International Journal of Costume Culture
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• 제13권1호
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• pp.1-4
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• 2010

The hand printed cottons of India are historically world-renowned for their rich fast colours, elaborate designs, and matchless quality. Until the discovery of synthetic dyestuffs in the latter part of the nineteenth century, the unsurpassed master dyers of cotton were the craftsmen of India-birthplace of cultivated cotton. The Indian printers and dyers monopolised this arcane art of permeating cotton cloth with richly hued, colour-fast designs, and the fruits of their labour proved hugely influential in international trade and the development of modern textile technologies. This paper focuses on a lesser-known body of hand printed cottons, traditionally produced in rural Rajasthan for everyday use by the local pastoral communities. Drawing on extensive research carried out with the region's Chhipa community of hereditary cloth printers, the complex and multiple applications of mordant, dye and resist are illustrated. Often taking months to complete, the enduring popularity of these labour-intensive hand printed cottons is then discussed, particularly in the light of the hugesocial importance borne by cloth in Rajasthan. Cloth and clothing are widely recognised as indicators of social status, gender, rank, and individual and group affiliations. In addition, cloth and clothing have been established as indicators of social, economic, political and technological change. The paper concludes by drawing attention to the recent influx of machine-printed polyester textiles, often replicating the designs or colours of the traditional locally produced cottons. Thus women of the region, whilst using these modern synthetic textiles as part of newer ways of expressing their identity, also visibly retain the values associated with hand printed cottons and traditional dress codes.

• 한국염색가공학회지
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• 제23권2호
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• pp.69-75
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• 2011

A pre-treatment process has been developed for natural dyeing of wool by which the dyed materials have been imparted antimicrobial efficacy against both gram-positive and gram-negative bacteria durable up to 20 washes. In this process, wool fabrics were treated with citric acid under oxidizing condition prior to dyeing. The treated fabrics were then dyed with four different types of natural dye powders obtained from leaves of silver oak, wattle, tanner's senna and flame of forest. All the natural dyes produced yellowish brown colour on wool fabrics. The washing and light fastness properties of the fabrics subjected to pre-treatment were one grade higher compared to those of the dyed fabrics without pre-treatment. The pre-treated wool fabrics showed antimicrobial efficacy against both gram-positive bacteria (Staphylococcus aureus) and gram-negative bacteria (Escherichia coli). The fabrics dyed without pre-treatment showed antimicrobial efficacy against gram-positive bacteria (Staphylococcus aureus) only. The durability of antimicrobial efficacy was higher in pre-treated and dyed wool fabrics compared to the dyed fabrics without pre-treatment.

• 한국염색가공학회지
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• 제21권6호
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• pp.29-38
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• 2009

Natural dyes seem to be more profitable on human and environment, and recently they could be considered as a better alternative to synthesized dyes. The aim of the current work was to investigate the dyeing property and antimicrobial activity of commercial cotton fabrics dyed with kumazasa (usually called in japan) which is known as conventional japan bamboo leaves. Actually, the dyeability and antimicrobial property of dyed fabric with natural mordant/dyeing was compared with synthetic mordant/dye process. The results of this study obtained are as follows. The apparently colour of kumazasa leaves extract dyed fabrics showed with light green or slightly yellow-green. In colorfastness to washing, ${\Delta}E$ and K/S values of dyed fabrics with natural chitosan as mordant used was shown to be more excellent results, than was synthetic mordant used. However, the decrease rate was recorded nearly 50% when washing repeated 20 cycles. In result of antimicrobial effect for bacteria, the dyed fabrics didn't show the significant antimicrobial activity to the both dyed with and without mordant. Results of this investigation considered that low-cost, natural, bio-mordant are relatively effective in natural coloration.

• 한국재료학회지
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• 제27권7호
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• pp.353-358
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• 2017

Recycled cenosphere, which is a hollow shaped particle from fly ash, has become attractive as a building material due to its light weight and excellent heat insulation and soundproof properties. In this paper, we investigated the effect of cenosphere size on the physical and optical properties. High brightness of cenosphere as raw material is required for a wide range of ceramics applications, particularly in fields of building materials and industrial ceramic tiles. Cenospheres were sorted by particle size; the microstructure was analyzed according to the cenosphere size distribution. Cenospheres were generally composed of quartz, mullite, and amorphous phase. Colour measurement corresponding to chemical composition revealed that the contents of iron oxide and carbon in the cenospheres were the major factors determining the brightness of the cenospheres.