• 제목/요약/키워드: Luminous Intensity

검색결과 161건 처리시간 0.024초

난류확산화염의 화염구조와 연소특성에 관한 실험적 연구(2) (An Experimental Study on Flame Structure and Combustion Characteristics of Turbulent Diffusion Flame(II))

  • 최병륜;장인갑;최경민
    • 대한기계학회논문집B
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    • 제20권3호
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    • pp.1050-1060
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    • 1996
  • Recently, attention has been paid to the flame diagnostic by noncontact methods which dose not deform the flame shape. One of them is a method which is using the radical luminous intensity. Generally, this diagnostic method using radical luminous has been investigated its reliability by applying to laminar flame. This study, however, investigated each radical luminous signals through stocastical analysis like auto-correlation, cross-correlation, phase and coherence which were acquired from measuring radical luminous intensity of OH, CH, $O_{2}$, radicals in turbulent diffusion flame. To compare radical luminous intensity in flame with temperature, ion current and concentration , radious distribution of each properties was investigated and considered. In radical luminous intensity, correlation in the reaction zone of flame was higher than in correlation in combusted gas zone. And radious distribution of radical luminous intensity was corresponded with radious distribution of temperature, ion current and concentration. The result of the study confirms that a radical luminous flame diagnosis is possible in the turbulent diffusion flame.

치과 진료실의 조명에 관한 실태 조사연구 (A STUDY ON THE ILLUMINATION OF DENTAL CLINIC)

  • 최종인;김유리;동진근
    • 대한치과보철학회지
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    • 제44권4호
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    • pp.374-382
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    • 2006
  • Purpose: This study was designed to investigate the present conditions of illumination techniques in dental clinics in order to contribute improvement of operating environment. This study also aimed exploring qualitative and quantitative luminous intensity required for color temperature in dental clinic illumination, which was a critical part of esthetic dentistry. Materials and methods: A total of forty-eight local dental clinics were selected for sampling a) luminous intensity, and b) color temperature. The author measured the luminous intensity and the color temperature with lux meter and color meter respectively between 12pm and 2pm. The dental unit chair placed in the general operation positions were kept the distance 60 cm then all dental units were measured three times and averaged. The author measured the luminous intensity and color temperature with both common dental operating light and then without operating light in different office environments. The study was conducted under three conditions: 1 artificial illumination in clear day light 2. artificial illumination in cloudy day light, and 3. artificial illumination alone. Results : The results obtained were as follows. 1. The average luminous intensity in dental clinic lighting was 425 lux which was not sufficient to produce the optimal shade of the patient's teeth. Furthermore, the average luminous intensity even in full operating lighting was 9532 lux which fell short of the required level of 10,000 lux. 2. The average color temperature of all dental clinics surveyed was 5169 K which met the optimal range. However, only 33.3% fell in the correct region between 5,000-5,500 K as 25% were over 5,500 K and 41.6% were below 5,000 K. As a result, 66.7% were under insufficient color temperature conditions. 3. The dental unit chair placed next to a window, hence exposure to natural lighting, had significantly higher luminous intensity and color temperature compared to the dental unit chair which didn't have a window or natural lighting. 4. The data analysis revealed that only 6.3% of the dental clinic were met the standard of the average luminous intensity and color temperature.

선박용 실내조명기구의 배광에 따른 불쾌글레어 분석 (Analysis of Discomfort Glare by luminous intensity distribution of Marine Indoor Luminaires)

  • 조상희;김근율;유영문
    • 조명전기설비학회논문지
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    • 제28권3호
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    • pp.18-25
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    • 2014
  • In this paper, tried to find out the proper luminous intensity distribution for the cabin with low-level height by analyzing the changing tendency of discomfort glare according to luminous intensity distribution of marine indoor luminaires using Unified Glare Rating(UGR). First, we analyzed UGR of the indoor luminaires in the existing cabin, and then evaluated influence on luminous intensity distributions of marine indoor luminaire. The results showed that $cos^2{\Theta}$ distribution got almost low UGR results regardless of height and UGR 16.5 in cabin height of 2m. However, Gaussian distribution with the same beam angle showed that UGR results consistently increased by getting lower height and UGR 20.7 in the same height. In conclusion, the $cos^2{\Theta}$ distribution in consideration of luminous intensity on the direction of observer's eye was appropriate for general cabin indoor luminaires because it decreased UGR in the low-level height.

Plasma Jet의 동축평행 자계에 의한 영향에 관한 연구 ( 1 ) (A Study on the Influence of Coaxial Parallel Magnetic Field upon Plasma Jet)

  • 전춘생
    • 전기의세계
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    • 제22권2호
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    • pp.57-69
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    • 1973
  • The aim of this study was to investigate the behaviors of plasma jet under coaxial magnetic field in paralled with it for controlling optical characteristics and input power of plasma jet without impurity and instability of arc plasma column. Because the discharge characteristics of plasma jet were so distinctively different according to the existence or non-existence of magnetic field, the input power, luminous intensity of plasma jet and thermal efficiency were comparatively studied in respect of such variables as arc current, gap of electrode, quantity of argon flow, magnetic flux density, diameter and length of nozzle, with the use of several materials which were different in diameter and length of nozzel. The results were as follows; 1) The voltage tends to show a drooping characteristic at law current and then rises gradually. The luminous intensity of plasma jet increases exponentially with arc current. 2) Arc voltage increases and luminous intensity tends to decrease gradually as gap of electrode increases. 3) Arc voltage and luminous intensity tends to decrease gradually as gap of electrode increases. 3) Arc voltage and luminous intensity increase in accordance with the quantity of argon flow. 4) At first step, arc voltage increases to maximum value with the growth of flux density and then tends to show a gradual decrease. Luminous intensity decreases with the growth flux density. 5) Arc voltage decreases as the constriction length of nozzle increases, maximum decrease is shown at the constriction length of 20(mm) and it increases beyond that value. The luminous intensity decreases as the constriction length grows. 6) Arc voltage and luminous in tensity increase with the growth of diameters of nozzle. 7) Thermal efficiency has values between 50% and 75%, being influenced by arc current, the quantity of argon flow, flux density, the length of electrode gap and the constriction length of nozzle.

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간접 반사형 LED 조명기구의 반사판 형태에 따른 배광형태 및 조명환경 변화 분석 (Analysis of the Change of Intensity Distribution and Luminous Environment by Reflector Shape in Indirect Reflected LED Luminaires)

  • 김유신;최안섭
    • 조명전기설비학회논문지
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    • 제25권1호
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    • pp.9-17
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    • 2011
  • Development of high efficiency and eco-friendly LED source has been progressed continuously. Also, by nation's regulations, public institutions have changed existing luminaires to LED luminaires. However, there are several differences between existing luminaires and the intensity distribution of general planar LED luminaires. In case of changing existing luminaires to LED luminaires, by such differences, there are inefficiencies both quality aspect and energy aspect in luminous environment. Therefore, this study aims to conduct a study on the changes of intensity distribution and luminous environment by reflector shapes in indirect reflected LED luminaires with software for optical design of a luminaire (Photopia 2.0) and lighting design of a space (ReluxPro). This study shows the changes of intensity distribution and luminous environment of indirect reflected LED luminaires and indirect fluorescent lamp luminaires by reflector shapes.

LED 보안등의 광균일도 향상을 위한 비구면 Mirror형 광학 설계에 관한 연구 (A Study of Aspheric Mirror Optical Design to Improve Luminous Intensity Uniformity of LED Security Lights)

  • 정인호;윤철용;예인수;현동훈
    • 한국생산제조학회지
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    • 제20권1호
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    • pp.114-119
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    • 2011
  • There is a limit to technology of improving luminous intensity uniformity and glare, known as a weakness of existing LED lamp. Because of Using many LED, LED lamp not only waste energy but have bad effect on efficiency. Our goal is to develop security lights solution which is contented with suitable area in KS(Korean Industrial Standards) and to remove glare by combining asphere in optical system with different concept. To improve luminous intensity uniformity, a reflect mirror system was used after an aspheric optical system design for this study. We made a mirror and measured it after analysing luminance changes depend on aspheric shapes with simulation program to see if aspheric shapes effect luminance distribution. We made progress to find problems and improve them by comparing measured data and analysed data. This result of the study will contribute to industry of LED lighting through developing solution of emotional illumination of LED security lights by knowing the importance of reflectivity with this study and improving luminous intensity uniformity with solving the problem.

난류확산화염의 화염구조와 연소특성에 관한 실험적 연구 (An Experimental Study on Flame Structure and Combustion Characteristics of Turbulent Diffusion Flame(III))

  • 장인갑;최경민;최병륜
    • 대한기계학회논문집B
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    • 제20권7호
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    • pp.2326-2336
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    • 1996
  • So most practical combustor is considered to the swirl flame, it is very important to examinate swirl flame structure and combustion characteristics. Recently, attention has been paid to the flame diagnostic by radical luminous intensity. For swirl flame structure and combustion characteristic, reverse flow boundary, temperature, ion current and radical luminous intensity were measured in the double-coaxial swirl combustor which was used principle of multi-annular combustor. This study had three experimental condition, S-type, C-type, SC-type. S-type and C-type flames were formed recirculation zone, but SC-type flame wasn't formed. C-type flame had two recirculation zone. The position with maximum value of ion current and CH-radical, temperature and OH-radical had similarity distribution almost. Therefore, it is possible that the macro structure of flame was measured by radical luminous intensity in the high intensity of turbulent combustion field which was formed by swirl.

LEDs 광조성 및 광도가 베이비채소의 생육 및 기능성물질에 미치는 영향 (Response of Growth and Functional Components in Baby Vegetable as Affected by LEDs Source and Luminous Intensity)

  • 윤성탁;정인호;김영중;한태규;유제빈;제은경
    • 한국유기농업학회지
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    • 제23권3호
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    • pp.549-565
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    • 2015
  • LEDs 광원 및 광도에 따른 베이비채소 6작물의 생육 특성과 기능성물질 함량을 구명하고자 Fluorescent lamp (100, 125, $150{\mu}mol\;m^{-2}s^{-1}$), Red+Blue 1:1 (100, 125, $150{\mu}mol\;m^{-2}s^{-1}$), Red+Blue 2:1 (100, 125, $150{\mu}mol\;m^{-2}s^{-1}$), Red+Blue 4:1 (100, 125, $150{\mu}mol\;m^{-2}s^{-1}$) 광원하에서 파종 40일 후에 수확하여 조사한 결과는 다음과 같다. 1. 베이비채소의 엽수는 시금치를 제외한 비트, 치커리, 적상추, 쑥갓, 겨자에서 Red+Blue(4:1) $150{\mu}mol\;m^{-2}s^{-1}$ 처리에서 가장 많았다. 2. 초장은 비트를 제외한 치커리, 시금치, 적상추, 쑥갓, 겨자에서 Red+Blue(4:1) $150{\mu}mol\;m^{-2}s^{-1}$ 처리에서 가장 높았다. 3. 생체중과 건물중은 비트, 치커리, 시금치, 적상추, 쑥갓, 겨자에서 Red+Blue(4:1) $150{\mu}mol\;m^{-2}s^{-1}$ 처리에서 가장 높았다. 4. 엽록소 a, 엽록소 b 함량은 시금치, 적상추, 겨자가 대조구인 Fluorescent lamp $150{\mu}mol\;m^{-2}s^{-1}$에서 가장 높았다. 5. 총 안토시아닌과 총 폴리페놀 함량은 비트, 치커리, 시금치, 적상추, 쑥갓, 겨자에서 Red+Blue(4:1) $150{\mu}mol\;m^{-2}s^{-1}$ 처리에서 가장 높았다. 6. Free radical 소거능은 비트, 치커리, 시금치, 적상추, 쑥갓, 겨자의 $150{\mu}mol\;m^{-2}s^{-1}$에서 높았지만 LEDs 광원별로는 차이를 보이지 않았다. 이상의 결과를 종합해 볼 때 비트, 치커리, 시금치, 적상추, 쑥갓, 겨자의 베이비 채소를 Red+Blue (4:1) $150{\mu}mol\;m^{-2}s^{-1}$에서 재배한다면 더욱 좋은 생육 효과를 기대할 수 있고 기능성 물질 함량도 다른 광도와 비교하여 상대적으로 좋았으므로 추후 상기의 베이비채소 생산 시 유용한 기초자료가 될 것으로 생각된다.

치과 기공실의 조명에 관한 실태 조사 연구 (A study of illumination of dental laboratories)

  • 이효정;최종인;김성숙;동진근
    • 구강회복응용과학지
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    • 제30권4호
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    • pp.289-298
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    • 2014
  • 목적: 본 연구는 치과 기공실의 조명이 심미 보철을 위한 색조의 분별과 조화, 재현에 적당한지 알아보기 위한 실태 조사이다. 연구 재료 및 방법: 48곳의 치과 기공실을 대상으로 lux meter와 color meter를 이용하여 포세린 작업대(porcelain table) 상판 중심의 조도와 색온도를 측정 하였다. 각각의 기공실을 자연광(day light)과 인공조명(artificial illumination)이 있는 오후 12시 - 2시 사이와 인공조명 만이 있는 오후 7시 - 10시 사이, 2차례 측정하였고, 맑은 날과 흐린 날로 구분하였다. 결과: 1. 전체 기공실의 평균 조도는 1871 lx이었고, 67%의 기공실이 1600 lx를 넘겨 색과 관련한 작업을 하기에 적합한 조도를 갖추었으나 33%의 기공실은 이에 미치지 못하였다. 2. 전체 기공실의 평균 색온도는 6506 K로 색과 관련한 작업을 하기에 부적절하였다. 적정 색온도인 5000 - 5500 K를 만족하는 기공실은 없었다. 3. 전체 기공실의 낮과 밤의 조도(P = 0.73) 및 맑은 날과 흐린 날의 조도(P = 0.89)와 낮과 밤의 색온도(P = 0.17) 및 맑은 날과 흐린 날의 색온도(P = 0.51)는 유의한 차이를 보이지 않았다. 결론: 본 연구에서 조사된 치과 기공실의 조명은 색과 관련한 작업을 하기에 부적절한 경우가 많았다.

반사 광학계를 이용한 LED Simulation 분석 (LED simulation analysis using optical system of reflex)

  • 윤철용;노명재;김병만;정병조;노용기
    • 한국산학기술학회:학술대회논문집
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    • 한국산학기술학회 2010년도 추계학술발표논문집 1부
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    • pp.159-162
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    • 2010
  • There are some limitations to advance technology glaring and luminous Intensity uniformity known as the weak point of existing LED lamp. To improve the two weak points, there have been no special alternative methods so far. Instead, one method which is being used such as the twisting secondary lens or arbitrary structure to remove glaring and improve luminous Intensity uniformity. Based on this academic background, it is necessary to be examined on Technology of Optical System to solve the two weak points by using not complicated but simple methods. This paper will examine the angle of reflection in order to improve luminous intensity uniformity. Also, this research will present the method using lighting analysis program to verify a hypothesis. Through the analysis program, we could understand the simulation analysis method and got some problems about the analysis result. After analysis of causes through reinterpretation of problems, we have reached a conclusion that was changed according to reflectivity and the shape of aspherics by main cause which effected luminous Intensity uniformity and glaring.

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