• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.369-369
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• 2007

The physical and visual evaluation of the identical X-rays are analyzed for medical image clarity with CD-RAD Phantom on this study. The method of measurement is to research CD-RAD by X-rays and to acquire images through image processing equipment, the image analyses are carried out by physical evaluation with statistical method through CD-RAD analyser program, and the visual evaluation of the identical X-rays is carried out by blind test for 20 observers. The result of it is that IQF value of the physical evaluation of Contrast-detail curve is 25 and IQF value of the visual evaluation is 30, so it is revealed that the physical evaluation is superior to the visual one. The special qualities of medical images have much importance of the transmission capacity of information to the image analyser, so it is concluded that 0비ective methods of the physical and visual analyses should be carried out side by side.

• Korean Journal of Bronchoesophagology
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• v.18 no.2
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• pp.45-48
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• 2012

Background Neoplastic vessels tend to proliferate on the surface of malignant lesions in the aerodigestive tract. So, superficial malignant lesions can be detected earlier by enhancing mucosal vascular clarity. To enhance mucosal vascular clarity on endoscopic image, we developed an image processing algorithm of RGB (red-green-blue) channel substitution image (CSI). Methods Each pixel in original white light image (WLI) has its own value of red, green and blue channel. Various combinations of RGB channel substitution was tried on original WLI. Results To make superficial blood vessels darker than brighter background mucosa, in the CSI algorithm, RGB value in each pixel of WLI is substituted; red value to green one, green value to blue one. There was a good contrast between superficial mucosal vessels and background brighter mucosa in the CSI image. Conclusion By RGB CSI algorithm, WLI could be successfully converted to new images with enhanced mucosal vascular clarity. Using RGB CSI algorithm could provide added vascular visibility on original WLI.

• Journal of the Korean Institute of Gas
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• v.21 no.5
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• pp.1-8
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• 2017

Currently gas safety management in the industrial field has been done by LDAR as contact method or methane leak detector as non-contact method. But LDAR method requires a lot of man-power and methane leak detector have the limitation of methane only. Therefore the Research on the OGI(optical gas image) has big attention by industry. This research was undertaken to see the effect of background temperature difference of gas cloud on the clarity of OGI. The background temperature control panel was constructed to cool down the background temperature. OGI was taken at the various methane gas ejection rate and the designed temperature difference. The experimental results showed that the OGI(when the temperature difference is $-6^{\circ}C$) is more clear thane the OGI(when the temperature difference is zero). To quantify the clarity difference, MATLAB's RGB analysis method was employed. The RGB value of the OGI at ${\Delta}T-6^{\circ}C$ was 20% lower than the OGI at ${\Delta}T0^{\circ}C$. The clarity difference by T difference can be explained by the total radiation law. When the background temperature of the gas is lower than the air temperature, the radiation energy coming into the OGI lens is increasing. As the energy is increasing, the OGI image becomes clear.

• Korean Journal of Remote Sensing
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• v.26 no.5
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• pp.581-591
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• 2010

In this paper, we proposed a new wavelet-based image fusion algorithm, which has advantages in both frequency and spatial domains for signal analysis. The developed algorithm compares the ratio of SAR image signal to optical image signal and assigns the SAR image signal to the fused image if the ratio is larger than a predefined threshold value. If the ratio is smaller than the threshold value, the fused image signal is determined by a weighted sum of optical and SAR image signal. The fusion rules consider the ratio of SAR image signal to optical image signal, image gradient and local variance of each image signal. We evaluated the proposed algorithm using Ikonos and TerraSAR-X satellite images. The proposed method showed better performance than the conventional methods which take only relatively strong SAR image signals in the fused image, in terms of entropy, image clarity, spatial frequency and speckle index.

• International Journal of Computer Science & Network Security
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• v.24 no.1
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• pp.163-177
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• 2024

The fingerprint image quality relies on the clearness of separated ridges by valleys and the uniformity of the separation. The condition of skin still dominate the overall quality of the fingerprint. However, the identification performance of such system is very sensitive to the quality of the captured fingerprint image. Fingerprint image quality analysis and enhancement are useful in improving the performance of fingerprint identification systems. A fuzzy technique is introduced in this paper for both fingerprint image quality analysis and enhancement. First, the quality analysis is performed by extracting four features from a fingerprint image which are the local clarity score (LCS), global clarity score (GCS), ridge_valley thickness ratio (RVTR), and the Global Contrast Factor (GCF). A fuzzy logic technique that uses Mamdani fuzzy rule model is designed. The fuzzy inference system is able to analyse and determinate the fingerprint image type (oily, dry or neutral) based on the extracted feature values and the fuzzy inference rules. The percentages of the test fuzzy inference system for each type is as follow: For dry fingerprint the percentage is 81.33, for oily the percentage is 54.75, and for neutral the percentage is 68.48. Secondly, a fuzzy morphology is applied to enhance the dry and oily fingerprint images. The fuzzy morphology method improves the quality of a fingerprint image, thus improving the performance of the fingerprint identification system significantly. All experimental work which was done for both quality analysis and image enhancement was done using the DB_ITS_2009 database which is a private database collected by the department of electrical engineering, institute of technology Sepuluh Nopember Surabaya, Indonesia. The performance evaluation was done using the Feature Similarity index (FSIM). Where the FSIM is an image quality assessment (IQA) metric, which uses computational models to measure the image quality consistently with subjective evaluations. The new proposed system outperformed the classical system by 900% for the dry fingerprint images and 14% for the oily fingerprint images.

• Imaging Science in Dentistry
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• v.34 no.3
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• pp.145-150
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• 2004

Purpose: To compare three digital radiographic imaging sensors by evaluating the visibility of endodontic file tips with interobserver reproducibility and assessing subjectively the clarity of images in comparison with the x-ray film images. Materials and Methods: Forty-five extracted sound premolars were used for this study. Fifteen plaster blocks were made with three premolars each and #8, 10, 15 K-flexofiles were inserted into the root canal of premolars. They were radiographically exposed using periapical x-ray films (Kodak Insight Dental film, Eastmann Kodak company, Rochester, USA), Digora imaging plates (Soredex-Orion Co., Helsinki, Finland), CDX 2000HQ sensors (Biomedisys Co., Seoul, Korea), and CDR sensors (Schick Inc., Long Island, USA). The visibility of endodontic files was evaluated with interobserver reproducibility, which was calculated as the standard deviations of X, Y coordinates of endodontic file tips measured on digital images by three oral and maxillofacial radiologists. The clarity of images was assessed subjectively using 3 grades, i.e. plus, equal, and minus in comparison with the conventional x-ray film images. Results: Interobserver reproducibility of endodontic file tips was the highest in CDR sensor (p < 0.05) only except at Y coordinates of #15 file. In the subjective assessment of the image clarity, the plus grade was the most frequent in CDR sensor at all size of endodontic file (p < 0.05). Conclusion : CDR sensor was the most superior to the other sensors, CDX 2000HQ sensor and Digora imaging plate in the evaluation of interobserver reproducibility of endodontic file tip and subjective assessment of image clarity.

• International Journal of Contents
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• v.18 no.1
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• pp.1-16
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• 2022

With the advent of the 5G, networks and information and communication technologies have been continuously developed. In the fields of art galleries, virtual reality (VR) exhibitions that can be visited online have emerged, innovating the way of human-computer interaction and creating new artistic experiences for users. This study explores the three-dimensionality, clarity, and innovative interactions that users experience when viewing a VR exhibit, which affects the exhibit's presence. Besides, in terms of research method, the research sets spatial participation and immersion as dependent variables, with three-dimensionality (high versus low), clarity (high versus low), and innovation (high versus low) in a 2×2×2 design as the base, and explores their interaction effects. The results show that three-dimensionality and innovative interactions affect spatial participation. First of all, in groups with high innovation and low three-dimensionality, spatial participation presents a higher positive factor. Secondly, with regard to immersion, three-dimensionality, clarity and innovation present a tripartite interaction. Groups with low three-dimensionality and high clarity have a higher positive effect on immersion when the level of innovation is low. When the degree of innovation is high, the positive effect on immersion is higher in groups with high three-dimensionality and low clarity. The above results show that in the production of VR exhibitions, it is necessary to increase the three-dimensionality and clarity of exhibited image contents, while taking into account the user's perception and innovativeness. On the other hand, this study puts forward suggestions for the design, content and future development of VR exhibitions, which has important reference significance for the improvement and innovation of future VR exhibitions.

• Journal of the Korean Data and Information Science Society
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• v.19 no.3
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• pp.723-734
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• 2008

The main reason for deinterlacing is frame-rate conversion. The other reason for deinterlacing is of course improve clarity and reduce flicker. Using a deinterlacer can help clarity and stability of the image. Many deinterlacing algorithms are available in image processing literatures such as ELA and E-ELA. This paper propose a new statistical deinterlacing algorithm based on statistical tests such as the Bartlett test, the Levene test and the Kruskal-Wallis test. The results obtained from the proposed algorithms are found to be comparable to those from many well-known deinterlacers. However, the results in the proposed deinterlacers are found to be more efficient than other deinterlacers.

• Journal of the Korean Society for Precision Engineering
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• v.15 no.7
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• pp.36-43
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• 1998

Surface roughness of cold rolled steel sheet as well as the coating technique itself is quite important in obtaining high image clarity of electronic products and car outer panels. Especially, surface characteristics of steel sheet have acquired increasing attention from the steel and automotive industries. While the influence of such characteristics on paintability formability and painted surface appearance is important in defining steel surface requirements for automotive industries. Therefore this paper is dedicated primarily to the issue of paint appearance and reviews for improvement of roughness and peak count about the surface of work roll for the actual temper mill. The conclusions were obtained as follows ; 1) Roughness and peak count about the surface of steel sheet is strongly affected by surface condition of work roll. 2) The electro-discharge textured roll has more uniform roughness distribution than shot blasted roll and it's painted appearance of steel sheet has more improvement than that of the shot blasted because it has more harmonic wave roughness, and the higher peak count of surface roughness.

• Korean Journal of Digital Imaging in Medicine
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• v.11 no.2
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• pp.115-119
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• 2009

I think this will be valuable reference for assuring consistency and homogeneity of clarity and managing dental radiation equipment by experimentation of dental radiation equipment permanent which based on KS C IEC 61223-3-4 standard and KS C IEC 61223-2-7. Put a dental radiation generator and experiment equipment as source and film(sensor) length within 30 em, place the step-wedge above the film(sensor). Tie up tube voltage 60 kVp, tube current 7 mA and then get an each image through CCD sensor and film by changing the exposure time as 0.12sec, 0.25sec, 0.4sec. Repeat the test 5times as a same method. Measure the concentration of each stage of film image, which gained by experiment, using photometer. And the image that gained by CCD sensor, analyze the pixel value's change by using image J, which is analyzing image program provided by NIH(National Institutes of Health). In case of film, while 0.12sec and 0.25sec show regular rising pattern of density gap as exposure time's increase, 0.4sec shows low rather than 0.12sec and 0.25sec. In case of CCD sensor density test, the result shows opposite pattern of film. This makes me think that pixels of CCD's sensor can have 0~255 value but it becomes saturation if the value is over 255. The way that getting clear reception during decreasing human's exposed radiation is one of maintaining an equipment as a best condition. So we should keeping a dental radiation equipment's condition steadily through cyclic permanent test after factor examination. Even digital equipment doesn't maintain a permanent, it can maintain a clarity by post processing of image so that hard to set it as standard of permanent test. Therefore it would be more increase the accuracy that compare a film as standard image. Thus I consider it will be an important measurement to care for dental radiation equipment and warrant homogeneity, consistency of dental image's clarity through comparing pattern which is the result from factor test against cyclic permanent test.