• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2006.11a
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• pp.275-278
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• 2006

In this paper we have compared three materials which are used for background in virtual studio. Each material reflects the illumination in different ways. In our experimental comparison, the 'chromatte' have the best quality in making good background image. Without predetermined light condition, chromatte provides wide range of adaptability.

• Journal of Satellite, Information and Communications
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• v.7 no.2
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• pp.36-41
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• 2012

In this paper we have compared three materials which are used for background chromakey in virtual studio. Each material reflects the illumination in different ways. In our experimental comparison, the 'chromatte' have the best quality in making good background image. Without predetermined light condition, chromatte provides wide range of adaptability.

• Journal of Information Processing Systems
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• v.14 no.6
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• pp.1405-1419
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• 2018

An image fusion method is proposed on the basis of depth model segmentation to overcome the shortcomings of noise interference and artifacts caused by infrared and visible image fusion. Firstly, the deep Boltzmann machine is used to perform the priori learning of infrared and visible target and background contour, and the depth segmentation model of the contour is constructed. The Split Bregman iterative algorithm is employed to gain the optimal energy segmentation of infrared and visible image contours. Then, the nonsubsampled contourlet transform (NSCT) transform is taken to decompose the source image, and the corresponding rules are used to integrate the coefficients in the light of the segmented background contour. Finally, the NSCT inverse transform is used to reconstruct the fused image. The simulation results of MATLAB indicates that the proposed algorithm can obtain the fusion result of both target and background contours effectively, with a high contrast and noise suppression in subjective evaluation as well as great merits in objective quantitative indicators.

• Journal of The Korean Astronomical Society
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• v.29 no.spc1
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• pp.1-5
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• 1996

Recent discussions of observational constraints on the standard hot big bang model are reviewed and it is argued that now there is room for considering alternative cosmologies. The quasi-steady state cosmology is briefly described. This model seems to explain most of the observed features of the universe, including the m-z relation, radio source count, the light nuclear abundances and the microwave background.

• The Bulletin of The Korean Astronomical Society
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• v.43 no.1
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• pp.48.2-48.2
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• 2018

SPHEREx is expected to provide us with the opportunity of unbiased sampling of small Solar System objects along with near-infrared ($0.75-5.0{\mu}m$) spectroscopic (R ~ 41) information. The estimated numbers of detections are tens of thousands for asteroids, thousands for Trojans, hundreds for comets, and several for Kuiper Belt Objects, Centaurs and Scattered Disk Objects. Wide spectral range covering many bands from carbon-bearing molecules and ices will enable us to systematically survey the volatile materials throughout the Solar System. SPHEREx will, for the first time, produce the near-infrared spectral map of the zodiacal light to pin-down the relative contributions of various populations of Solar System objects and interstellar dust to the dust grains in the interplanetary space. The study of the zodiacal light is also important to remove the foreground for the EBL (extragalactic background light) study, one of the main topics of the mission.

• Proceedings of the IEEK Conference
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• 2006.06a
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• pp.941-942
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• 2006

A depth measurement system to recognize 3D shape of objects using single camera, line laser and a rotating mirror has been investigated. The camera and the light source are fixed, facing the rotating mirror. The laser light is reflected by the mirror and projected to the scene objects whose locations are to be determined. The camera detects the laser light location on object surfaces through the same mirror. The scan over the area to be measured is done by mirror rotation. The Segmentation process of object recognition is performed using the depth data of restored 3D data. The Object recognition domain can be reduced by separating area of interest objects from complex background.

• Fisheries and Aquatic Sciences
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• v.19 no.6
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• pp.28.1-28.7
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• 2016

Background: Significant increases in the bacterial resistance to various antibiotics have been found in fish farms. Non-antibiotic therapies for infectious diseases in aquaculture are needed. In recent years, light-emitting diode technology has been applied to the inactivation of pathogens, especially those affecting humans. The purpose of this study was to assess the effect of blue light (wavelengths 405 and 465 nm) on seven major bacterial pathogens that affect fish and shellfish important in aquaculture. Results: We successfully demonstrate inactivation activity of a 405/465-nm LED on selected bacterial pathogens. Although some bacteria were not fully inactivated by the 465-nm light, the 405-nm light had a bactericidal effect against all seven pathogens, indicating that blue light can be effective without the addition of a photosensitizer. Photobacterium damselae, Vibrio anguillarum, and Edwardsiella tarda were the most susceptible to the 405-nm light (36.1, 41.2, and $68.4J\;cm^{-2}$, respectively, produced one log reduction in the bacterial populations), whereas Streptococcus parauberis was the least susceptible ($153.8J\;cm^{-2}$ per one log reduction). In general, optical density (OD) values indicated that higher bacterial densities were associated with lower inactivating efficacy, with the exception of P. damselae and Vibrio harveyi. In conclusion, growth of the bacterial fish and shellfish pathogens evaluated in this study was inactivated by exposure to either the 405- or 465-nm light. In addition, inactivation was dependent on exposure time. Conclusions: This study presents that blue LED has potentially alternative therapy for treating fish and shellfish bacterial pathogens. It has great advantages in aspect of eco-friendly treating methods differed from antimicrobial methods.

• Korean Journal of Environmental Agriculture
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• v.30 no.4
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• pp.382-389
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• 2011

BACKGROUND: Light-emitting diodes (LEDs) with lower electric cost and the specific wavelength have been considering as a novel light source for plant production in greenhouse conditions as well as in a closed culture system. Supplementary lighting for day-length extension was considered as light intensity, light quality, and/or photoperiod control on plant growth and development. Effects of supplementary blue or red LED radiation with lower light intensity on growth of Ageratum (Ageratum houstonianum Mill., cv. Blue Field), African marigold (Tagetes erecta L., cv. Orange Boy), and Salvia (Salvia splendens F. Sello ex Ruem & Schult., cv. Red Vista) were discussed during sunrise and sunset twilight in the experiment. METHODS AND RESULTS: Supplementary lighting by blue and red LEDs for 30 (Treatment B30; R30) or 60 (Treatment B60; R60) min. per day were established in greenhouse conditions. Photosynthetic photon flux for supplementary radiation was kept at $15{\mu}mol\;m^{-2}\;s^{-1}$ on the culture bed. Natural condition without supplementary light was considered as a control. The highest shoot and root dry weights were shown in African marigold exposed by red light for 60 min. per day. Supplementary blue and red lighting regardless of the radiation time significantly stimulated development of lateral branches in African marigold. Stem growth in Ageratum and Salvia seedlings was significantly promoted by red radiation as well as natural light. CONCLUSIONS: Extending of the radiation time at sunrise and sunset twilight using LEDs stimulated reproductive growth of flowering plant species. Different characteristics on growth under supplementary blue or red lighting conditions were also observed in the seedlings during supplementary radiation.

• Journal of dental hygiene science
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• v.23 no.2
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• pp.123-131
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• 2023

Background: As a restorative material used to treat dental caries, the light-curing type resin is widely used, but it has the disadvantage of polymerization shrinkage. The Bulk-Fill composite resin was developed to solve these shortcomings, but the existing research mainly focused on comparing the physical properties of a composite resin and a Bulk-Fill resin. A study on the light curing time and distance of the Bulk-Fill resin itself tend to be lacking. Methods: This study compares the surface microhardness of specimens prepared by varying the light curing time and distance of smart dentin replacement (SDR) as a flowable Bulk-Fill resin and Tetric N-ceram as a packable Bulk-Fill resin, and confirms the polymerization time and distance that becomes the optimum hardness. To determine the hardness of the specimen, it was measured using the Vickers Hardness Number (Matsuzawa MMT-X, Japan). Results: In SDR, the surface microhardness decreased as the distance increased in all time groups in the change distance from the curing tip. In the change of light curing time with respect to the distance from curing tip, the surface microhardness increased as the time increased. In Tetric N-ceram, the surface microharness showed no significant difference in the change of the distance of curing tip in the group of 20 and 60 second. But in the group of 10 and 40 seconds, decreased as the distance increased. The surface microharness increased as the light curing time increased in all distance groups. Conclusion: When using SDR and Tetric N-ceram in clinical practice, it is considered that as the distance from the polymerization reactor tip increases, a longer light curing time than the polymerization time recommended by the manufacturer is required.

• Journal of the Korean Society of Clothing and Textiles
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• v.26 no.11
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• pp.1627-1637
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• 2002

The objective of this study is to analyze the images of basic bodice apparel displayed on the PC monitor connected to digital camera, and to suggest a more efficient alternative method that enables the expert judge to evaluate the subject both traditional method and displayed images on the computer. Appearance evaluation has traditionally been assessed using subjective method dependent upon expertjudges' senses with the naked eye after direct observation of a living model. This research faces the new challenge focusing on the sensory evaluation of appearance for basic apparel patterns, which can overcome the space and time limitations of the traditional feet methods. A total fifteen basic bodice garment (3 types of $pattern\;{\times}\;5$ subject) were constructed with same fabrics. The appearance evaluation items consist of lg questions of upper torso. The image takes font, back and side view of the dressed subject with three different situations. Data was analyzed using percentiles, standard deviation T-test and ANOVA. Taken together, the present result of appearance evaluation through digital camera image shows that there is a significant difference ($p{\leq}.001$) in the response to the placement of the neckline, the waist & shoulder dart, the general ease of the bust & waist area, the side seam, the perpendicular of the waist hem and general acceptability between the above three different situations; the image in the condition of greenish yellow background with front light showed the highest score through all questions. These results depend on the kind of background colors with the light.