• 제목/요약/키워드: color calculation

검색결과 151건 처리시간 0.023초

보정된 X-색도 좌표를 이용한 색온도 변환 시스템의 성능 개선 및 구현 (Performance Improvement and Implementation of Color-Temperature Conversion System using Compensated X-Chromaticity Coordinate)

  • 변형수;강봉순;양훈기
    • 대한전자공학회논문지SD
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    • 제41권1호
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    • pp.61-70
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    • 2004
  • 본 논문은 보정된 X-색도 좌표를 이용한 색온도 변환 방법을 제안하고자 한다. 제안된 방법은 기존의 색온도 변환 시스템에서 문제점인 색온도 계산값의 오차를 줄이기 위하여 회귀방정식을 사용한다 또한, 광범위한 영역에서 색온도 변환을 실현하기 위하여 색온도 영역을 1,667K에서 25,000K까지 확대하고자 한다. 제안한 방법은 Robertson 방법 및 기존의 색온도 계산방법과 성능의 비교분석을 통하여 타당성을 보이고자 한다. 본 논문에서 제안된 방법은 하드웨어로 설계하여 Xilinx FPGA인 XCV2000E-BG560를 통하여 TV 시스템에서 실시간으로 동작을 검증한다.

정적 예혼합기 연소에 있어서 2영역 모델 및 2색법에 의한 연소온도 비교에 관한 연구 (A Study on Comparisons Between Combustion Temperatures Calculated by Two-Region Model and Measured by Two-Color Method in Premixed Constant-Volume Combustion)

  • S.K.Lee
    • Journal of Advanced Marine Engineering and Technology
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    • 제23권3호
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    • pp.300-310
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    • 1999
  • A constant-volume combustion chamber is developed to measure the burnt gas temperature over the wide ranges of equivalence ratio from 1.5 to 2.7 and pressure from 0.1 to 2.7 and pressure from 0.1 to 6 MPa by two-color method. The combustion temperature is also calculated by the conventional two-region model. The premixed fuel rich propane-oxygen-inert gas mixtures under high pressures are simultaneously ignited by eight spark plugs located on the circumference of combustion chamber with 45 degree intervals. The eight converging flames compress the end gases to high pressures. The transmissiv-ity in the chamber center during the final stage of combustion at the highest pressure is measured by in situ laser extinction method. Comparisons are made with the combustion temperatures between two-color method and two-region model. It is found that the burnt gas temperature mea-sured by two-color method is higher than that calculated by two-region model because of being the negative temperature gradient on the calculation and the temperature distribution of light path-length on the measurement and the burnt gas temperature for the turbulent combustion is higher than that of the laminar combustion under the same conditions because the heat loss for turbulent combustion is lower due to the shorter combustion period.

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체질에 따른 컬러테라피의 피부관리 적용방법의 안(案) (A Study on Personal Color Therapy practice to Skin Care)

  • 류지혜;성광숙
    • 한국의류산업학회지
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    • 제10권6호
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    • pp.1014-1022
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    • 2008
  • This study focuses on practical appliance of color therapy to skin care. After visiting the notion of color therapy and skin care, this study considers the ideas and background theories for diagnosis of constitution and skin. Cosmic duals force five element theory developed in China was the first introduction; Ayurvedic medicine and seven chakra notion are examined. Cosmic duals force five element theory, an idea describing the composition and movement rule of the cosmic components, adopted five colors(white, yellow, red, blue, and black) for cure purposes. In future, mental effect of the color is examined in the latter part of this study. The practice of the color therapy assigns solarized cream treatment and photo therapy, simultaneously proposes the use of color therapy to the skin care. For the diagnosis of the constitution, cosmic duals force five element theory and ayurvedic medicine are followed in a sequence. Cosmic duals force five element theory introduces five colors. Constitution medicine considers four types, ayurvedic medicine adopts three types, and seven colors are mentioned as chakra colors. Such a variations lead to possible disagreement on constitution analysis and driven colors. This study adopts the above methodologies for selecting potential color therapy for skin care. Adopt of selected cases are purely a part of the proposal. Initially, examined theories serve as a pilot for selecting a representative hypothesis. Followed selection of constitution and matched color for the use of the skin care are the scope of this study. In summary, background methodologies are implemented for the calculation of color therapy.

Consideration of NDVI and Surface Temperature Calculation from Satellite Imagery in Urban Areas: A Case Study for Gumi, Korea

  • Bhang, Kon Joon;Lee, Jin-Duk
    • 한국측량학회지
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    • 제35권1호
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    • pp.23-30
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    • 2017
  • NDVI (Normalized Difference Vegetation Index) plays an important role in surface land cover classification and LST (Land Surface Temperature Extraction). Its characteristics do not full carry the information of the surface cover typically in urban areas even though it is widely used in analyses in urban areas as well as in vegetation. However, abnormal NDVI values are frequently found in urban areas. We, therefore, examined NDVI values on whether NDVI is appropriate for LST and whether there are considerations in NDVI analysis typically in urban areas because NDVI is strongly related to the surface emissivity calculation. For the study, we observed the influence of the surface settings (i.e., geometric shape and color) on NDVI values in urban area and transition features between three land cover types, vegetation, urban materials, and water. Interestingly, there were many abnormal NDVI values systematically derived by the surface settings and they might influence on NDVI and eventually LST. Also, there were distinguishable transitions based on the mixture of three surface materials. A transition scenario was described that there are three transition types of mixture (urban material-vegetation, urban material-water, and vegetation-water) based on the relationship of NDVI and LST even though they are widely distributed.

소부(少府)(HT8) 레이저 침 시술이 정신적 스트레스를 가한 성인의 심박변이도에 미치는 영향 (Effect of Laserneedle Aupuncture Therapy for Mental Stress on Heart Rate Variability)

  • 박현철;강문수;김락형
    • 동의신경정신과학회지
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    • 제18권3호
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    • pp.113-122
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    • 2007
  • The purpose of this study was to evaluate the effects of mental stress measured with heart rate variability(HRV) in healthy adults and to evaluate the effects of laserneedle acupuncture therapy in healthy adults. Methods : 25 healthy volunteers participated in this study. The volunteers were divided randomly, the real laserneedle acupuncture therapy group or the sham laserneedle acupuncture therapy group. First, After 5 minute rest, mental stress was given with stroop color word task and calculation task. And then laserneedle acupuncture therapy or sham laserneedle therapy was done on HT8(少府) for 15 minute. HRV was recorded in 3 period-before stress, after stress, and after laserneedle or sham acupuncture therapy. Results : LF was significantly increased after mental stress. And there was no significant difference between the real laserneedle acupuncture therapy group and the sham laserneedle acupuncture therapy group. Conclusions : This results show that mental stress-stroop color word test and calculation test for 10 minute- contribute to activation of the sympathetic nervous system.

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내용기반 영상검색 시스템 (Content-based Image Retrieval System)

  • 유헌우;장동식;정세환;박진형;송광섭
    • 대한산업공학회지
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    • 제26권4호
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    • pp.363-375
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    • 2000
  • In this paper we propose a content-based image retrieval method that can search large image databases efficiently by color, texture, and shape content. Quantized RGB histograms and the dominant triple (hue, saturation, and value), which are extracted from quantized HSV joint histogram in the local image region, are used for representing global/local color information in the image. Entropy and maximum entry from co-occurrence matrices are used for texture information and edge angle histogram is used for representing shape information. Relevance feedback approach, which has coupled proposed features, is used for obtaining better retrieval accuracy. Simulation results illustrate the above method provides 77.5 percent precision rate without relevance feedback and increased precision rate using relevance feedback for overall queries. We also present a new indexing method that supports fast retrieval in large image databases. Tree structures constructed by k-means algorithm, along with the idea of triangle inequality, eliminate candidate images for similarity calculation between query image and each database image. We find that the proposed method reduces calculation up to average 92.9 percent of the images from direct comparison.

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헤드램프의 시계성 평가를 위한 야간 도로 영상 재현 알고리즘 (An reproduction algorithm of nighttime road-image for visibility evaluation of headlamps)

  • 이철희;하영호
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2000년도 추계종합학술대회 논문집(4)
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    • pp.69-72
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    • 2000
  • This study proposes a new calculation method for generating real nighttime lamp-lit images. In order to improve the color appearance in the prediction of a nighttime lamp-lighted scene, the lamp-lit image is synthesized based on spectral distribution using the estimated local spectral distribution of the headlamps and the surface reflectance of every object. The principal component analysis method is introduced to estimate the surface color of an object, and the local spectral distribution of the headlamps is calculated based on the illuminance data and spectral distribution of the illuminating headlamps. HID and halogen lamps are utilized to create beam patterns and captured road scenes are used as background images to simulate actual headlamp-lit images on a monitor. As a result, the reproduced images presented a color appearance that was very close to a real nighttime road image illuminated by single and multiple headlamps.

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학교 교실 LED 조명의 색온도에 대한 주관적 평가 (Subjective Evaluation on the Color Temperatures of LED illumination in the Classroom)

  • 지순덕;김채복
    • 조명전기설비학회논문지
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    • 제25권1호
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    • pp.30-41
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    • 2011
  • This study performs the subjective evaluations of LED illumination conditions according to three types of color temperatures (7,000[K], 5,000[K], 3,000[K]) after employing LED illumination system in the classroom, Since the objective of this study is to develop an artificial lighting conditions like day light comfortable to students in the classroom, the learning effect based on three types of LED illumination conditions are analyzed. Three factors (learning intention, learning environment, learning motivation) are extracted by ANOVA and there are preference differences of LED illumination conditions between learning intention and learning environment factors. Especially, preference differences of LED illumination conditions are existed about calculation, reading and fatigue reduction. The test results of this study can be applied to obtaining high achievement of learning based on the lighting conditions.

모바일 기기용 게임 개발을 위한 가변 인덱스 컬러 응용 (Applications of Variable Indexed Colors for Game Development of Mobile Devices)

  • 정종필;김치훈
    • 한국콘텐츠학회논문지
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    • 제8권11호
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    • pp.49-56
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    • 2008
  • PC나 콘솔 기반의 게임들은 탁월한 하드웨어 지원에 힘입어 화려한 3D 효과와 이펙트 등을 보여주고 있지만, 다양한 컨버전스 또는 모바일 기기들은 상대적으로 가벼운 하드웨어 사양과 배터리 시간의 한계 때문에 계산양이 적은 가벼운 게임들을 선호하고 있다. 이러한 하드웨어 상의 게임 제작에 있어 최소한의 그래픽 품질을 유지하는 것은 매우 중요하다. 본 논문에서는 인덱스 컬러(Indexed Color) 팔레트를 하드 웨어 사양을 극복하여 발전시킬 수 있는 방법으로 제안 한다.

A fast single image dehazing method based on statistical analysis

  • ;방성배;김원하
    • 한국방송∙미디어공학회:학술대회논문집
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    • 한국방송∙미디어공학회 2018년도 하계학술대회
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    • pp.116-119
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    • 2018
  • In this paper, we propose a new single-image dehazing method. The proposed method constructs color ellipsoids that are statistically fitted to haze pixel clusters in RGB space and then calculates the transmission values through color ellipsoid geometry. The transmission values generated by the proposed method maximize the contrast of dehazed pixels, while preventing over-saturated pixels. The values are also statistically robust because they are calculated from the averages of the haze pixel values. Furthermore, rather than apply a highly complex refinement process to reduce halo or unnatural artifacts, we embed a fuzzy segmentation process into the construction of the color ellipsoid so that the proposed method simultaneously executes the transmission calculation and the refinement process. The results of an experimental performance evaluation verify that compared to prevailing dehazing methods the proposed method performs effectively across a wide range of haze and noise levels without causing any visible artifacts. Moreover, the relatively low complexity of the proposed method will facilitate its real-time applications.

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