• 환경생물
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• 제22권1호
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• pp.89-92
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• 2004

The effects of different light quality on the change of membrane potential difference (PD) of the guard cell in the intact leaf have been investigated. The mombrane PD was about -5.5 mV by white light of 600 $\mu$moles $m^{-2}\; s^{-1}$. The mean PD of change caused by red light was about -5.2 mV at the light intensity of 80 $\mu$moles $m^{-2}\; s^{-1}$. Membrane PD of guard cells in response to blue light was saturated at low light intensity. However, red and green light enhanced the change of membrane PD of guard cells with increasing intensity. In green light the biggest change of memrane PD was around -4 mV, whereas, with blue light the change of of memrane PD was around -2 mV. Accordingly, the membrane PD of guard cell showed the different degree of hyper-polarization by each wavelength.

• 한국정보통신학회논문지
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• 제25권2호
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• pp.221-227
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• 2021

최근 발광다이오드를 이용한 마스크 형식의 피부 관리기에 관한 관심이 증가하고 있으며, 특정 파장의 광학적 자극은 노출 광량 및 파장대, 광선 조사 시간을 조절함으로써, 피부 미백, 여드름 치료, 탄력 및 주름 개선 등과 같은 다양한 효과를 보인다고 알려져 왔다. 특히, 피부 노화 억제, 세포증식 유도, 피부의 염증 완화 등을 목적으로 하는 마스크의 경우 각각 다른 파장의 광원이 사용된다. 본 논문에서는 마이크로컨트롤러를 사용하여 피부재생 마스크에 활발하게 사용되는 발광다이오드 제어시스템을 개발하였다. 단일 또는 복합적으로 피부 섬유아세포에 인가하여, 세포의 증식에 어떠한 효과가 있는지 확인한다. 또한, 세포증식률에 긍정적 효과를 보이는 특정 파장대를 찾아 다양한 자극에 기인한 세포증식 효과를 확인하고, 영상처리를 활용한 정량분석법을 제시하여 그 효과를 평가하였다.

• 한국발생생물학회지:발생과생식
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• 제20권1호
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• pp.23-29
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• 2016

In fish, light (photoperiod, intensity and spectra) is main regulator in many physiological actions including growth. We investigate the effect of light spectra on the somatic growth and growth-related gene expression in the rearing tiger puffer. Fish was reared under different light spectra (blue, green and red) for 8 weeks. Fish body weight and total length were promoted when reared under green light condition than red light condition. Expression of somatostatins (ss1 and ss2) in brain were showed higher expression under red light condition than green light condition. The ss3 mRNA was observed only higher expression in blue light condition. Expression of growth hormone (gh) in pituitary was detected no different levels between experimental groups. However, the fish of green light condition group was showed more high weight gain and feed efficiency than other light condition groups. Our present results suggest that somatic growth of tiger puffer is induced under green light condition because of inhibiting ss mRNA expression in brain by effect of green wavelength.

• 한국식품과학회지
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• 제47권6호
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• pp.785-788
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• 2015

식품 저장 중 효소적 갈변을 일으키는 타이로시네이스의 활성을 저해시킬 수 있는 LED의 파장을 구명하기 위하여 파란색, 초록색, 빨간색 LED와 형광등을 이용하여 타이로시네이스에 7일동안 조사하였다. 또한 강도에 따른 타이로시네이스의 활성을 조사하기 위하여 파란색, 초록색, 빨간색 LED를 선택하여 빛의 강도를 3단계로 구분하여 사용하였다. 파장에 따른 타이로시네이스의 활성 저해율은 형광등에서 가장 컸으며 그 다음으로 파란색 LED에서 높은 저해율을 보였다. 빨간색 LED에서는 대조구와 유사한 저해율을 보였으며 초록색 LED에서 저해율이 가장 낮았다. 상대적 빛의 강도에 따른 타이로시네이스 활성은 초록색과 빨간색 LED 조사 시 효소활성의 변화가 크지 않았고, 반면 파란색 LED에서 강도가 증가할수록 큰 저해효과를 보였다. 이러한 결과를 토대로 볼 때 여러 가지 파장의 LED 중 고강도의 파란색 LED에서 타이로시네이스에 의한 식품의 갈변을 최소화 할 수 있을 것으로 판단되며 이는 갈변 억제를 유도함으로써 과일 및 채소의 저장 중 품질을 향상시킬 수 있을 것이다.

• 한국광학회지
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• 제22권3호
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• pp.122-128
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• 2011

하향신호를 위해서는 반사형 반도체 증폭기를 기반으로 한 광역선폭 광원 기술이 사용되었고 상향신호를 위해서는 파장 재사용 기술이 사용된 양방향 파장분할 다중화 수동 광네트워크 (WDM-PON)가 컴퓨터 시뮬레이션을 통해 구현되었다. 이 시스템에서 세가지 다른 종류의 광필터들이 비교되어 필터링의 영향이 분석되었고, 광 스펙트럼과 아이 다이어그램 (eye diagram)의 분석을 통해 파장 재변조 기술을 최적화 하였다. 최적화된 시스템 조건을 이용하여 양방향 신호의 전송 성능 곡선을 구하였고 이 시스템에서 반사에 의한 신호 왜곡의 영향을 분석하였다.

• 한국염색가공학회지
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• 제13권3호
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• pp.165-171
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• 2001

In this study, UV/vis. spectra of color solution extracted from onion shell and dyeing properties of polyamide fibers such as wool, silk, and nylon were investigated. Also, the effect of mordanting on wash fastness and light fastness was Investigated. The amount of colors extracted was increased with extracting temperature and time. The wavelength of maximum absorption of onion shell extract corresponds to flavonol peak and quercetin peak. Also, spectra of color solution were shifted to longer wavelength at higher pH values. It appeared that the optimum condition of the dyeing of wool, nylon, and silk fabrics with onion shell extract was $60^\circ{C}$ , 30min, and pH 4.0 of dyed bath. Surface colors of the dyed fabrics were different according to the used mordants: Al and Cr mordanted fabrics were dyed in yellowish colors, Cu mordanted fabric in greenish color, Sn mordanted fabric in orange color, and Fe mordanted fabric in khaki color. The mordanting was effective at improving wash fastness and light fastness.

• 한국어업기술학회:학술대회논문집
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• 한국어업기술학회 2000년도 춘계수산관련학회 공동학술대회발표요지집
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• pp.153-154
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• 2000

Many bioactive photosensitizers have been isolated from plants and some of theses possess antiviral activities which, depend on UVA(320-400nm) and visible light. Many complex quinonoids have been isolated from plants and recently some of them, such as hypericin and hypocrellin, have been shown to possess light-dependent antiviral activities. these compounds only exert their desired biological activities in the presence of long wavelength ultra-violet UVA but these activities are also strongly influenced b chemical structure(Hudson et al, 1995). the importance of light in the use of certain medicinal plant extracts has been appreciated, if not understood, for centuries. Also, many seaweed extracts will effect photo(UVA, visible light) for algicidal activity. (omitted)

• 태양에너지
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• 제13권2_3호
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• pp.133-139
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• 1993

본 논문은 순수한 CdS 박막시편에 미소량의 불순물(활성제)을 첨가하고 각 시편에 대한 파장(380-760nm) 및 온도변화($120-360^{\circ}K$)에 따른 전기적 특성을 비교, 조사 하였다. 그 결과는 다음과 같다. 1) 순수한 CdS 박막의 경우 열처리함에 따라 저항이 증가 하였으며 분광응답의 최대치는 더욱더 장파장쪽으로 이동하였다. 2) 여러가지 일정한 온도에서 여러가지 파장의 광을 조사하였을때 실온도에서 보다는 저온도($160^{\circ}K$)에서 민감한 광응답특성을 나타냈다. 3) 불순물의 첨가량이 0.5wt%일 때 비교적 양호한 광응답특성을 나타내고 있다.

• 센서학회지
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• 제31권3호
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• pp.151-155
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• 2022

In this paper, we present a highly-sensitive gate/body-tied (GBT) metal-oxide semiconductor field-effect transistor (MOSFET)-type photodetector using multi-finger structure whose photocurrent increases in proportion to the number of fingers. The drain current that flows through a MOSFET using multi-finger structure is proportional to the number of fingers. This study intends to confirm that the photocurrent of a GBT MOSFET-type photodetector that uses the proposed multi-finger structure is larger than the photocurrent per unit area of the existing GBT MOSFET-type photodetectors. Analysis and measurement of a GBT MOSFET-type photodetector that utilizes a multi-finger structure confirmed that photocurrent increases in ratio to the number of fingers. In addition, the characteristics of the photocurrent in relation to the optical power were measured. In order to determine the influence of the incident the wavelength of light, the photocurrent was recorded as the incident the wavelength of light varied over a range of 405 to 980 nm. A highly-sensitive GBT MOSFET-type photodetector with multi-finger structure was designed and fabricated by using the Taiwan semiconductor manufacturing company (TSMC) complementary metal-oxide-semiconductor (CMOS) 0.18 um 1-poly 6-metal process and its characteristics have been measured.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 춘계학술대회 초록집
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• pp.88.2-88.2
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• 2010

Dye-sensitized solar cells (DSSCs) have attracted considerable attention on account of their high solar energy-to-conversion efficiencies and low cost processes compared to conventional p-n junction solar cells. The mechanism of DSSC is based on the injection of electrons from the photo excited dyes into the conduction band of the semiconductor electrode. The oxidized dye is reduced by the hole injection into either the hole conductor or the electrolyte. Thus, the light harvesting effect of dye plays an important role in capturing the photons and generating the electron/hole pair, as well as transferring them to the interface of the semiconductor and the electrolyte, respectively. We used the organic fluorescence materials which can absorb short wavelength light and emit longer wavelength region where dye sensitize effectively. In this work, the DSSCs were fabricated with fluorescence materials added $TiO_2$ photo-electrode which were sensitized with metal-free organic dyes. The photovoltaic performances of fluorescence aided DSSCs were compared, and the recombination dark current curves and the incident photon-to-current (IPCE) efficiencies were measured in order to characterize the effects of the additional light harvesting effect in DSSC. Electro-optical measurements were also used to optimize the fluorescence material contents on TiO2 photo-electrode surface for higher conversion efficiency (${\eta}$), fill factor (FF), open-circuit voltage (VOC) and short-circuit current (ISC). The enhanced light harvesting effect by the judicious choice/design of the fluorescence materials and sensitizing dyes permits the enhancement of photovoltaic performance of DSSC.