• Journal of the Korean Society of Tobacco Science
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• v.16 no.1
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• pp.26-33
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• 1994

A tobacco ripeness grading meter was designed and constructed using the color sensor, its performance was evaluated. A degree of ripeness grading of a leaf is very closely related to the measured tobacco leaf color. Measuring the small amount of the reflectance precisely depends on the apparatus including color sensor, light source, detector sensitivity, and geometric characteristics of appratus. To analyze and minimize the variational effects, experiments to select the proper condition were performed. Because of the combined effect mentioned above, the system has some variation on its response. Basis on the results of the experiments, prototype was developed and interfaced to a computer system. The main components of prototype included a tungsten lamp as a light source, Amorphous full color sensor with three filters, regulated D.C. power supply, OP - AMP(741 TC) for amplification, AR - B3001 board for interfacing to a computer with analog to digital conversion, and a compatible IBM PC XT computer. The experimental results of the developed ripeness tobacco leaf measurement system are summarized as following: [1] The output readings of ripeness grade meter for tobacco leaf, which is based on harvesting time, showed the apparent difference in variety of different quality. It was considered suitable that three filters(red, green, blue) in Amorphous full color sensor could be used in four different ripeness degree measurement of tobacco leaf. [2] The output readings of ripeness grade meter for tobacco leaf, which is based on government procurement, showed apparent difference in variety of different quality. Tobacco leaf varieties to stalk position are divided into tips, leaf, cutters, and primings, It is considered suitable that only red filter in the sensor could be used to classify the grade of tobacco leaf within the same kind tobacco stalk. However, the ripeness grade meter was not adequate to classify all the tobacco grades in the four different tobacco leaves.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.59 no.4
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• pp.444-449
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• 2010

The PID control to the monitor color correction was applied. Converted Gamma LUT was applied to the video card. Color and brightness information from the PID controller was used as control inputs. Color and brightness information from a calibrated monitor is measured again. Then, the difference between the preset values for the PID controller was compensated by the feedback. The software measured by color meter was used for color and brightness information. All of the monitor does not measure the color and brightness was measured by sampling. The color and brightness from the monitor were measured not by complete enumeration but by sampling. In the experiment, the original image was displayed on the same monitor as well as two other brands, and then, Gamma and Contrast were measured and compared.

• IE interfaces
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• v.11 no.2
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• pp.139-147
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• 1998

The purpose of this study is to survey colors of background, marker, and pointer being used in passenger car's combination meter, and to suggest ergonomic design guidelines of combination meter to enhance driver's readability. An experiment was conducted, in which colors of background, marker, and pointer were selected as independent variables, and reading time, reading error, and preference for combination meter were measured as dependent variables. Most of passenger cars sold in Korea were found to have combination meter with black background, while marker. The experimental results showed that reading time of combination meter with white background, black marker and point was shortest, reading error was lowest in combination meter with black background, yellow marker pointer, and preference for combination meter with white background, black marker and black or red pointer was highest. The results implied that combination meter with white background, black marker and black pointer should be used for comprehensively optimizing reading time, reading error, and preference for it. It was expected that these results could be used as valuable design guidelines when designing combination meter of passenger car.

• Journal of the Ergonomics Society of Korea
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• v.7 no.1
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• pp.13-20
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• 1988

The purpose of this study is to provide basic research data on the readability of the car number license plate in Korea by experimental procedure. This study is performed by the combination of color contrasts, character forms, and stroke widths. Additionally it is focused on the distance of distinct vision and misreading rate. The results of the this study are as follows: First, as to the color contrasts, the plate which has black on yellow contrast has better readability than current contrast between white and green (white character on green plate, vice versa). Second, as the character forms, it is showed that Quasigothic and NAMEL types have less misreading rates by 42.86% and 42.15%, respectively, than current Gothic type, and they also increase distance of distant vision by 4 meter. Third, as to the stroke widths, it is showed that 12 milli-meter and 14 milli-meter of stroke widths have less misreading rates by 63.94% and 65.33 %, respectively, than current 6 milli-meter of stroke width.

• The Journal of Korean Academy of Prosthodontics
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• v.47 no.3
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• pp.348-355
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• 2009

Statement of problem: Although the use of colorimeter to improve the accuracy of tooth color measurement has increased, it is real situation that there is almost no comparative study about the accuracy among various colorimeters. Purpose: The purpose of this study is to compare the accuracy of porcelain color reproducibility using ShadeEye-Ncc dental chroma meter (Shofu Inc., Kyoto, Japan) and Shadepilot$^{TM}$ system (Degudent Inc., Hanau, Germany). Material and methods: Color of 2M2 and 3M2 shade tap of Vitapan 3D Master shade guide were measured using the above two colorimeters. Porcelain specimens were fabricated through this data. The porcelain systems used were Vintage Halo Porcelain system with ShadeEye-Ncc dental chroma meter, and VitaOmega900 Porcelain system with Shadepilot$^{TM}$ system. Colors of shade tap models and porcelain specimen were measured with spectrophotometer, and calculated delta E based on the results. Results: The following results were obtained. 1. Shadepilot$^{TM}$ system showed more suitable porcelain color reproducibility compared to ShadeEye-Ncc dental chroma meter (P <.05). 2. The result showed the difference of porcelain color reproducibility according to shade of Shade tap which is model. More suitable porcelain color reproducibility was shown at 3M2 shade tap than at 2M2 shade tap (P <.05). 3. The average of ${\Delta}E*$ of porcelain specimens which was made by the two colorimeters was 4.44-6.14, so the difference of shade was shown through the naked eye. Conclusion: Shadepilot$^{TM}$ system showed more suitable porcelain color reproducibility. When using ShadeEye-Ncc dental chromameter, it will be necessary to improve accuracy through coloring various parts of the whole tooth.

• Journal of Biosystems Engineering
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• v.18 no.4
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• pp.382-389
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• 1993

In this research, the surface color of 'Fuji' apples and tomatoes were measured by using Sharp PD 151 semiconductor color sensors. The measurements were compared with color-difference-meter readings and with visual sensory test scores. A negative exponential function was developed which describe the relationship between the dominant wavelength of the surface color of 'Fuji' apples and the ratio of the photoelectric currents of the color sensor. Also a linear relationship was found for the surface color of tomatoes and the color sensor output. There were good correlations between the visual test scores and the color sensor output for both 'Fuji' apples and tomatoes.

• Journal of Dental Rehabilitation and Applied Science
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• v.30 no.4
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• pp.289-298
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• 2014

Purpose: This study was designed to investigate the present conditions of illumination techniques in dental laboratories in order to distinguish colors for esthetic dentistry. Materials and Methods: A total of forty-eight local dental laboratories were selected for sampling a) luminous intensity and b) color temperature. We measured the luminous intensity and the color temperature on a center point of porcelain table with lux meter and color meter respectively. The measurements were performed twice, once on a clear day and on a cloudy day between 12 pm and 2 pm (day light and artificial illumination) and between 7 pm and 10 pm (artificial illumination only). Results: The results obtained were as follows. 1. The average luminous intensity in dental laboratories lighting was 1871 lx, and 67% of dental laboratories had luminous intensity greater than 1600 lx, which was appropriate for operations related to colors, while 33% of dental laboratories had in sufficient lighting for appropriate luminous intensity. 2. The average color temperature in dental laboratories lighting was 6506 K, which was inappropriate for operations related to color. None of the dental laboratories had a color temperature range of 5000 - 5500 K, which is appropriate for operations related to colors. 3. Between daytime and nighttime, also between clear day and cloudy day, the average luminous intensity and color temperature in dental laboratories were not significantly different. Conclusion: Illumination in most dental laboratories selected in this study was inappropriate for operations related to color.

• Journal of the Korean Society of Food Science and Nutrition
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• v.13 no.1
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• pp.1-8
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• 1984

The tools and techniques for measuring the spectral distribution of light emitted by, transmitted by, or reflected from food surfaces are described for determining the extent to which original natural color is preserved in processing and subsequent storage of foods. Color differences may be evaluated indirectly in terms of some physical characteristic of the sample or extracted fraction thereof that is largely responsible for the color characteristics. For evaluation more directly in terms of what the observer actually seen, color differences are measured by reflectance spectrophotometry and photoelectric colorimetry and expressed as differences in psychophysical indexes such as luminous reflectance and chromaticity. The standard system, against which other systems could be compared, is the one recommended by the International Committee on illumination and which is based on the 'standard observer', which is a simulated standard eye, consisting of three primary color filters Z, with X being essentially amber in color, Y, green and Z, blue. Any spectrophotometric curve of reflectance obtained from the surface of an object can be integrated in terms of X, Y and Z. Psychophysical notation may be converted by standard methods to the colorimetrically more descriptive terms of Munsell hue, value and chroma.

• Journal of the Korean Society of Clothing and Textiles
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• v.30 no.6 s.154
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• pp.971-980
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• 2006

The colors of apparel have a close relationship with the facial color types of consumers. To extract the favorable colors that flatter to consumer's facial color types, the facial colors of Korean females were analyzed. With color meter JX-777, 2 points of face were measured and classified into 3 clusters that had similar hue, value and chroma. Other new 10 college girls were measured and 3 subject among them were selected by the criteria that choose new subjects who have the classified facial color types. 175 respondents answered the degree of becomingness of color samples on three subjects. Data were analyzed by K-means cluster analysis, ANOVA and Duncan multiple range test using SPSS Win. 12. Findings were as follows: 1) 324 subjects who had YR facial colors were classified into 3 facial color groups. The average facial color Type 1 was 4.82YR 6.47/3.70 and composed 48.88% among total observations. Type 2 was 5.99YR 6.12/4.12 and 30.25%. Type 3 was 5.15YR 7.07/4.97 and 20.99% respectively. 2) Favorable colors for Type 1 were 18 colors that belonged to 'a' group from among colors that were divided into a, b, c group by Duncan post hoc test. 3) Type 2 showed that this type had many unfavorable colors. Unfavorable colors were 18 colors that belonged to 'c' by Duncan test. 4) Type 3 showed that black is the most favorable color and 18 colors were at middle level, which belonged to 'b' from among 18 colors that were divided into a, b, and c by Duncan test.

• Restorative Dentistry and Endodontics
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• v.26 no.2
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• pp.180-187
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• 2001

The structure of current guides is largely illogical and without any rational use of color ordering. The shade guides are generally made of plastic (rather than the actual composite material) and do not accurately depict the true shade. translucency. or opacity of the composite resin after polymerization. To solve this problem, information based on evaluations of natural teeth and material that use the same method and experimental conditions is necessary. The present investigation measured the color of natural maxillary anterior teeth in vivo and compared the results with those of composite resins. 269 Korean subjects were selected for this study. Intact central incisor. lateral incisor. and canine were selected. The clinical crowns were free of caries or restorations. The middle site of the coronal portion on the labial surface of the tooth was measured by Chroma Meter. The five light activated. resin-based materials (Amelogen, Denfil, Elitefil, Spectrum, Z100) were used in this study. Resin composite was condensed into plastic mold with a diameter of 8mm and a thickness of 4mm. pressed between glass plates to flatten the surfaces. and polymerized using a Visilux II visible light activation unit. The surfaces were polished sequentially on wet sandpaper. Color measurements of each specimen were accomplished by Chroma Meter. A computer program that compares each tooth color with each composite resin color was written and the minimum CIELAB color difference ($\Delta$E$^*$) between tooth and each material was calculated. Under the conditions of this study: 1. Teeth tend to become darker with advancing age. 2. Canines were darker. more yellow. and less green than incisors. 3. The teeth from the women were lighter. more green. and less yellow than the male teeth. 4. In general. composite resins were lighter. more green. and less yellow than teeth. Deficiencies were noted in Hues in YR range. 5. Mean color differences between the five composite resin products and teeth were detectable to the naked eye($\Delta$E$^*$>1.0). 6. In comparing the mean $\Delta$E$^*$ values of materials. Spectrum showed the least followed by Z100, Elitefil, Amelogen, Denfil in increasing order.