• 대한수학회지
• /
• 제47권5호
• /
• pp.935-945
• /
• 2010

The mixed width-integrals of convex bodies are defined by E. Lutwak. In this paper, the mixed brightness-integrals of convex bodies are defined. An inequality is established for the mixed brightness-integrals analogous to the Fenchel-Aleksandrov inequality for the mixed volumes. An isoperimetric inequality (involving the mixed brightness-integrals) is presented which generalizes an inequality recently obtained by Chakerian and Heil. Strengthened version of this general inequality is obtained by introducing indexed mixed brightness-integrals.

• 대한전자공학회:학술대회논문집
• /
• 대한전자공학회 2005년도 추계종합학술대회
• /
• pp.1291-1296
• /
• 2005

In this paper, we prevent a display quality drop for image of characteristics brightness ununiformity depend on LED use to LED vision. It is about that method also a control system development equipped with brightness compensation function of LED vision which is done easily for LED set up of LED vision. Generally, It is calculate driving current value is attended by each brightness to brightness characteristics mathematical function establish by "Y=aX+b", When is doing brightness value for "Y", driving current value for "X", brightness compensation value by using time for "b", characteristics value for "a" ground with characteristics curve of LED. So much, First It is create brightness data of each pixel take a photograph red, green and blue of LED vision. Second It is get average error about each pixel which get average brightness value of entire. Last, It is handle a complicated for about gradationally regulation to color and brightness of image send to LED vision. Also It raise the whole average brightness value of vision adjust for "b" value to solve brightness drop problem of LED using the long time.

• Journal of Electrical Engineering and Technology
• /
• 제10권4호
• /
• pp.1822-1829
• /
• 2015

In this study, artificial neural networks were used to determine the intensity of brightness in interior spaces. The illumination elements to illuminate indoor spaces were considered, not individually, but as a system. So, during the planned maintenance periods of an illumination system, after its design and installation, simple brightness level measurements must be taken. For a three-dimensional evaluation of the brightness level in indoor spaces in a speedy and accurate manner, the obtained brightness level measurement results and artificial neural network model were used. Upon estimation of the most suitable brightness level for indoor spaces by using the artificial neutral network model, the energy demands required by the illumination elements decreased. Consequently, in this study, with estimations of brightness levels, the extent to which the artificial neutral networks become successful was observed and more correct results have been obtained in terms of both economy and usage.

• 대한전자공학회:학술대회논문집
• /
• 대한전자공학회 2003년도 하계종합학술대회 논문집 Ⅳ
• /
• pp.2403-2406
• /
• 2003

When viewing images, the relative luminance of the surround has a profound impact on the apparent contrast of the image. The dark surround causes the image elements to appear lighter than those viewed in an illuminated surround. For this reason, it is worthwhile to briefly review the general results of brightness sealing under a various viewing condition. Two of the most often cited parers on the topic of brightness scaling are Stevens-stevens and Bartleson-Breneman's function. There are, however, significant differences between the perceptual functions for simple-field and complex-field viewing. In this paper, we research the relationship between Steven's power law and Bartleson-Breneman's function. We present an appropriate brightness perception function due to TV system viewing conditions. Highlight luminance peak and absolute brightness threshold value in various adaptation levels are obtained from the proposed brightness function . Also, the luminance value of black level to produce the same contrast ratio with variety of display highlight luminance peak is obtained from the proposed brightness function.

• 천문학회보
• /
• 제39권2호
• /
• pp.57.1-57.1
• /
• 2014

We present results of our investigation of intrinsic brightness temperatures of compact radio jets at radio frequencies. The intrinsic brightness temperatures of about 100 compact radio jets at 2, 5, 8, 15, and 86 GHz are estimated based on large VLBI surveys conducted in 2001-2003 (or in 1996 for the 5 GHz sample). The multi-freqeuncy intrinsic brightness temperatures of the sample of the jets are determined with a statistical method relating the observed brightness temperatures with the maximal apparent jet speed, assuming one representative intrinsic brightness temperature for the sample at each observing frequency. With investigating the observed brightness temperatures at 15 GHz in multiple epochs, we found that the determination of the intrinsc brightness temperature for our sample is affected by variability of individual jets in flux density at the time scales of a few years. This implies an importance of contemporaneity of the multi-frequency VLBI observations for the statistical method. Since our analysis is based on the VLBI observations conducted in 2001-2003, the results are less affected by the flux density variability. We found that the intrinsic brightness temperature $T_0$ increases as $T_0{\propto}{\nu}^{\epsilon}$ with ${\epsilon}{\approx}0.7$ below a critical frequency ${\nu}_c{\approx}10GHz$ where energy losses begin to dominate the emission, and above the critical frequency, $T_0$ decreases with ${\epsilon}{\approx}-1.2$ supporting for the decelerating jet model.

• 조명전기설비학회논문지
• /
• 제21권2호
• /
• pp.1-8
• /
• 2007

이 논문에서는 Lightscape를 사용할 때 보다 질적으로 나은 시뮬레이션 이미지를 산출하기 위해 각 재질에 따른 brightness 수치들을 변화시켜서 보다 사실적인 재질의 이미지를 표현하기 위한 최적의 brightness 수치를 산출하도록 하였다. 주간에 인공 광원의 광량과 강한 주광이 더해져서 광량이 초과되어 수치적으로 재질의 색이 변색되어 보이는 경우가 발생하기 때문이다. 그러므로 주간에는 낮은 수치의 brightness를 적용할 경우 재질의 느낌을 보다 사실과 근접하게 나타낼 수 있다는 결과를 추출하였다. 그리고 대부분의 재질들이 주간에는 낮은 brightness 수치를, 야간에 높은 brightness 수치를 입력하여야 원 재질의 RGB 데이터와 유사하여 가장 사실적인 시뮬레이션 이미지가 나온다는 사실을 알 수 있었다.

• 인지과학
• /
• 제17권4호
• /
• pp.337-356
• /
• 2006

본 연구에서는 시각디스플레이에서 단어와 배경간의 밝기, 대비부호, 색상 차이가 가독성 및 감성에 미치는 효과를 살펴보았다. 실험 1에서는 밝기차이(대, 중, 소)${\times}$대비부호(정적, 부적) 조건에 따른 가독성, 심미성, 선호도의 효과를 알아보았다. 실험 1의 결과, 밝기 차이가 커짐에 따라 가독성, 심미성, 선호도가 증가하였다. 실험 2에서는 실험 1 조건에 네 가지 색상 요인(초록, 빨강, 노랑, 파랑)을 추가하여 수행하였다. 그 결과 가독성에서는 밝기와 대비부호의 주효과, 밝기와 대비부호간의 상호작용효과가 유의미하였으며, 심미성과 선호도에서는 밝기, 대비부호, 색상의 주효과, 밝기와 색상간의 상호작용효과가 유의미하였다. 즉 밝기의 차이가 커짐에 따라 가독성, 심미성, 선호도가 증가하였으며, 정적대비가 부적대비에 비해 가독성, 심미성, 선호도가 더 좋았으며, 색상은 빨강, 파랑, 초록, 노랑 순으로 심미성과 선호도가 높은 결과를 보였다. 또한 가독성에서 밝기와 대비부호간의 상호작용효과는 밝기의 차이가 작은 조건에서 부적대비가 정적대비보다 반응시간이 길게 나타났기 때문인 것으로 보인다. 심미성과 선호도에서 밝기와 색상간의 상호작용효과가 나타난 것은 밝기 차이가 작은 조건에 비해 큰 조건에서 색상에 따른 심미성효과가 유의미하게 차이가 있었기 때문인 것으로 보인다. 실험 3에서는 텍스트 디자인과 단일색을 대상으로 18개의 감성 어휘를 평정하게 하여 감성의 유사성을 측정하였다. 그 결과, 특정 색이 지닌 주관적인 느낌이 텍스트 디자인에 잘 반영되기 위해서는 배경에 그 색을 사용하는 것이 더 적절하다는 결론을 얻었다.

• 천문학회지
• /
• 제46권6호
• /
• pp.243-251
• /
• 2013

We present results on the intrinsic brightness temperature of a sample of compact radio sources observed at 86 GHz using the Global Millimeter VLBI Array. We use the observed brightness temperatures at 86 GHz and the observed superluminal motions at 15 GHz for the sample in order to constrain the characteristic intrinsic brightness temperature of the sample. With a statistical method for studying the intrinsic brightness temperatures of innermost jet cores of compact radio sources, assuming that all sources have the same intrinsic brightness temperature and the viewing angles of their jets are around the critical value for the maximal apparent speed, we find that sources in the sample have a characteristic intrinsic brightness temperature, $T_0=4.8^{+2.6}_{-1.5}{\times}10^9K$, which is lower than the equipartition temperature for the condition that the particle energy equals to the magnetic field energy. Our results suggest that the VLBI cores seen at 86 GHz may be representing a jet region where the magnetic field energy dominates the total energy in the jet.

• 한국정보디스플레이학회:학술대회논문집
• /
• 한국정보디스플레이학회 2008년도 International Meeting on Information Display
• /
• pp.763-764
• /
• 2008

3D displays requires multiplexing of left and right pictures on the same screen so that they can be viewed independently by the view using various schemes, including LCD shutters, polarizers, narrow band filters, and lenticular lenses on the screen. All these methods reduce the effective screen brightness by as much as 10X. The eye responses to the lower brightness are analyzed and found to compensate partially giving a lower perceived brightness. This paper presents such eye response analysis and a low cost approach to increasing brightness in a RPTV using the long life DPR system, increasing the screen brightness by over 2.5 times, while maintaining acceptable lamp lifetime.

• 대한기계학회논문집A
• /
• 제28권4호
• /
• pp.362-369
• /
• 2004

LGP(Light-Guide Panel) of LCD backlight is one of the major componets which affect on the product quality of LCD. The optical relation between brightness and pattern has been investigated for LGP with the uniform distribution of brightness. When given the brightness distribution as target, the solutions of pattern distribution is not unique. Each solution of pattern designs shows the different brightness intensity even though they have the same brightness distribution with target's one. The manufacturing condition of pattern has an influence on the possibly-maximum-brightness intensity among the solutions of pattern design. The present study has examined the effects of LGP thickness, pattern shape errors, and reflection film on the optical characteristics of LGP.