• Title/Summary/Keyword: Luminous

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ON THE PHYSICAL BASIS OF THE TULLY-FISHER RELATION

  • RHEE MYUNG-HYUN
    • Journal of The Korean Astronomical Society
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    • v.37 no.1
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    • pp.15-39
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    • 2004
  • We analyse the results of mass models derived from the HI rotation! curves of spiral galaxies and find that the slope of the luminous mass-circular velocity relation is close to 4. The luminous mass-circular velocity relation with a slope of about 4 can be explained by an anti-correlation between the mass surface density of luminous matter and the mass ratio of the dark and luminous components. We also argue that the conspiracy between luminous and dark matter exists in a local sense (producing a flat or smooth rotation curve) and in a global sense (affecting the mass ratio of the dark and luminous matter), maintaining the luminous mass-circular velocity relation with a slope of about 4. We therefore propose that the physical basis of the Tully-Fisher relation lies in the luminous mass-circular velocity relation. While the slope of the luminous mass-circular velocity relation is fairly well defined regardless of the dark matter contribution, the zero-point of the relation is still to be determined. The determination of the slope of the Tully-Fisher relation needs one more step: the mean trend of the luminosity-luminous mass relation determines the overall shape (slope) of the Tully-Fisher relation. The key parameter needed to determine the zero-point of the luminous mass-circular velocity relation and the slope of the Tully-Fisher relation obviously is the luminous mass-to-light ratio.

The Influence of Luminous Source Affecting on the Perception of Textile Color (직물색의 지각에 미치는 광원의 영향)

  • Choi, Na-Young;Yang, Lee-Na;Lee, Jong-Sook
    • The Research Journal of the Costume Culture
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    • v.15 no.2 s.67
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    • pp.214-220
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    • 2007
  • The purpose of this study is to derive the use of the luminous source corresponding to the intention and contribute to product display by visually evaluating the relations between luminous source and colors, analyzing and reviewing the subjective perceptions depending on the luminous source, and clarifying the colors of artificial luminous source that look close to natural lights by each color. Hence, the researcher objectified the subjective evaluation for which they used sensory evaluation method with four colors of luminous sources(natural colors, 2800K, 4200K, and 6500K) and five colors of textiles(purple, blue, green, yellow, and red) by quantifying the evaluation. As a result, we could obtain the conclusion as follows. As for the temperature of textile colors under artificial luminous sources that appeared most close to the colors of textiles under natural luminous sources, 6500K was most frequent, and the temperature of the luminous sources that appeared most different was 2800K. However, as there were also 4200K colors that looked most close to the textile colors under natural light source, it was observed that the temperature differs depending on the textile colors. In addition, less glossy textiles exhibited more visual changes by luminous source colors than comparatively more glossy textiles, and it was observed that the most influenced color was purple, as purple has shown the largest difference among colors.

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Comparison of Measurement and Calculation Model of Solar Luminous Efficacy for All Sky Conditions in Seoul (천공구분에 따른 서울지역 일사의 발광효율 측정 및 예측모델과의 비교 연구)

  • Yoon, Kap-Chun;Yun, Gyeong;Kim, Kang-Soo
    • Journal of the Korean Solar Energy Society
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    • v.31 no.6
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    • pp.86-94
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    • 2011
  • For accurate dayligh tsimulation, accurate exterior illuminance is necessary. But, Korea Meteorological Agency provides only the solar irradiance data. Thus, there is a need for the research on luminous efficacy. In this study, global horizontal irradiance, diffuse horizontal irradiance, global horizontal illuminance, and diffuse horizontal illuminance were measured to calculate the luminous efficacy in SEOUL. And, we evaluated the applicability of the Perez's model by comparing the measured data and calculated data. As a result, measured global luminous efficacy is 126(110~129)lm/W and diffuse luminous efficacy is 127(115~133)lm/W in Seoul. Perez's model was relatively accurate with 5% difference in the diffuse luminous efficacy. But, it can be predicted about 15% lower in the global luminous efficacy.

Influence of luminous jig to catching of squid jigging in the Korean waters (오징어 채낚기 낚시의 야광이 어획에 미치는 영향)

  • RYU, Kyung-Jin;KIM, Hyung-Seok
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.55 no.4
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    • pp.303-309
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    • 2019
  • This study identified the characteristics of squid jig in korea waters by investigating the effect of color and luminous performance of squid jig on the catch of squid and experimenting the result of jig according to green jig or white jig, and whether using luminous or not were tested in the sea to improve the jig of squid jigging. For this purpose, a total of 13 sea experiments were conducted using T/S No. 2 Galmaegi. As a result, 341 squids were caught. Among them, 221 squids were caught by green jig (64.8%), 64 squids were caught by white jig (18.8%), 41 squids were caught by green luminous jig (13.8%), and nine squids were caught by white luminous jig (2.6%). The green jig commonly used in jigging vessel was most effective, and luminous jig was less effective than that non-luminous jig. The squids caught were Japanese flying squid (Todarodes pacificus), swordtip squid (Loligo edulis) and spear squid (Loligo bleekeri), and no significant characteristics were found according to the color of jig and the presence of luminous.

Discharge and Luminous Characteristics of Coplanar Type Xe Plasma Flat Lamp (면방전형 Xe 플라즈마 평판 램프의 방전 및 발광 특성)

  • Kim, Hyuk-Hwan;Lee, Won-Jong
    • Korean Journal of Materials Research
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    • v.21 no.10
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    • pp.532-541
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    • 2011
  • The Xe plasma flat lamp, considered to be a new eco-friendly LCD backlight, requires a further improvement of its luminance and luminous efficiency. To improve the performance of this type of lamp, it is necessary to understand the effects of the discharge variables on the luminous characteristics of the lamp. In this study, the luminous characteristics of a coplanartype Xe plasma flat lamp with a teeth-type electrode pattern were analyzed while varying the gas composition, gas pressure and input voltage. The effects of the phosphor layer on the discharge and the luminous characteristics of the lamp were also studied. The luminous efficiency of the coplanar-type Xe plasma flat lamp improved as the Xe input ratio and gas pressure increased. Higher luminous efficiency was also obtained when helium (He) was used as a buffer gas and when a phosphor layer was fabricated on the electrode region. In contrast, the luminous efficiency was reduced with increasing the input voltage. It was found that the infrared emissions from the lamp were affected by the Xe excitation rate in the plasma, the Xe gas density, the collisional quenching of excited Xe species by gas molecules, and the recombination rate between the Xe ions and electrons.

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

  • Choe, Byeong-Ryun;Jang, In-Gap;Choe, Gyeong-Min
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.20 no.3
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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.

Effect of Self-Erase Discharge on the Luminous Efficacy of Long Gap AC PDPs

  • Kim, Tae-Jun;Jung, Jae-Chul;Jung, Hae-Yoon;Whang, Ki-Woong
    • 한국정보디스플레이학회:학술대회논문집
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    • 2007.08a
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    • pp.585-588
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    • 2007
  • We studied the effect of self-erase discharge on the luminous efficacy of ac PDPs. We observed through discharge current analysis to confirm that the selferase discharge occurred mainly between sustain cathode and address electrode, which have an influence on the luminous efficacy. The amount and timing of the self-erase discharge was varied to observe its effect on the luminous efficacy. It has been found that the luminous efficacy could be improved by the self-erase discharge when it is adjusted to occur right before the main discharge in the small gap structure. In the long gap structure, on the contrary, the luminous efficacy could be increased when the self-erase discharge is suppressed. Also, various waveforms to control self-erase discharge are suggested and tested in the panel experiments.

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Improvement of Luminous Efficacy in AC PDP with Asymmetric Metal Electrode Structure (AC PDP의 효율 향상을 위한 비대칭형 금속전극구조)

  • Dong, Eun-Joo;Ok, Jung-Woo;Yoon, Cho-Rom;Lee, Hae-June;Lee, Ho-Joon;Park, Chung-Hoo
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.57 no.4
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    • pp.660-667
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    • 2008
  • To improve the luminous efficacy of PDPs, an AC PDP with new metal electrode structure is suggested. Operating voltage margin, power consumption, luminance, luminous efficacy, addressing jitter and ICCD image of test panel with proposed structure are measured, to compared with performances of the conventional ITO structure and proposed structures. To enhance luminous efficacy, we designed new structure which have asymmetric metal electrode structure. The experimental results show that the suggested structure shows luminance to maximum 89% and luminous efficacy to maximum 107% compared with conventional ITO standard structure. In addition, proposed structures with asymmetric electrode show low power consumption by $2{\sim}3%$, high luminance by $5{\sim}7%$, and high luminous efficacy by $2{\sim}3%$ compared with proposed symmetric electrode structures.

The Luminous Efficiency Improvement of Color AC Plasma Display Panel by adding Ar Gas (Ar Gas 첨가에 따른 칼라 플라즈마 디스플레이 패널의 효율 향상)

  • Shin, Jae-Hwa;Choi, Hoon-Young;Lee, Seok-Hyun
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.51 no.3
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    • pp.132-136
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    • 2002
  • In this study, we analyzed the luminous efficiencies of Ne-Xe-Ar and He-Ne-Xe-Ar mixing gas in compared with those of Ne-Xe and He-Ne-Xe mixing gas to improve luminous efficiency by adding a small amount of Ar gas. At the Xe 4%, the brightness of Ne-Xe and He-Ne-Xe mixing gas is higher than others. As the Xe % increases, power consumption decreases. Thus, in the Ne-Xe and He-Ne-Xe mixing gas of Xe 4%, we obtained maxium luminous efficiency. The Ar concentration is varied from 0.1% to 0.7% in this study. The luminous efficiency of the Ne-Xe(4%) mixing gas is improved to 1.16 and 1.13 lm/W by adding an Ar concentration of 0.4% and 0.5%, respectively. The luminous efficiency of the He-Ne-Xe(4%) (He : Ne = 7 : 3) mixing gas is considerably improved by adding an Ar concentration of above 0.3%. The maximum luminous efficiency of this mixing gas is 1.38 lm/W at the condition of adding an Ar concentration of 0.5%.

Predicting Daylight Illuminances on Vertical Surfaces Using Luminous Efficacy of SolarIr radiance (일사의 발광효율을 이용한 수직면 주광조도 예측에 관한 연구)

  • Yoon, Kap-Chun;Kim, Kang-Soo
    • Journal of the Korean Solar Energy Society
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    • v.34 no.1
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    • pp.19-27
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    • 2014
  • Exterior vertical illuminance is an important factor for lighting control. But, there are not many researches about the exterior illuminance on a vertical surface. In this study, we predicted the exterior illuminance on a vertical surface using vertical luminous efficacy. First, we calculated the vertical luminous efficacy according to the sky clearness category. And we performed the statistical analysis of the measured and the calculated illuminance with luminous efficacy. The MBE and RMSE of the predicted exterior illuminance were-1.2% and 15.5%, respectively. Second, the annual illuminance on a vertical surface calculated with the luminous efficacy and the short-term measured solar irradiance was suggested in this study.