• 상하수도학회지
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• 제30권1호
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• pp.33-40
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• 2016

In this study, a fluorescent silica nano particle is used as the surrogate for challenging test of membrane surface integrity. The particles are functionalized by a fluorescent dying agent so that as an ultraviolet light is imposed a bright fluorescent image from the particles can be taken. If a membrane surface is damaged and has a compromised part larger than the size of surrogate the fluorescent particles would pass through and contained in the permeate. An operator can directly notice whether the membrane surface is damaged or not by detecting a fluorescent image taken from the permeate. Additionally, the size of compromised part is estimated through analysing the fluorescent image in which we surmise the mass of particles included in the permeate by calculating an average RGB value of the image. The pilot scale experiments showed that this method could be applied successfully to determine if a membrane surface had a damaged parts regardless of the test condition. In the testing on the actual damaged area of $4.712mm^2$, the lowest error of estimating the damaged area was -1.32% with the surrogate concentration of 80 mg/L, flux of $40L/m^2/hr$ for 25 minutes of detection. A further study is still going on to increase the lowest detection limit and thus decrease the error of estimation.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.177-177
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• 2006

Copolymers containing oxime-urethane groups, which led to the formation of pendant amino groups photochemically, were applied to a fluorescent image-recording material through the reaction with fluorescamine, a prefluorescent dye for amino groups. This imaging method permits the fluorescent image to be erased or restored by treatment with base or acid. Copolymers containing phthalimide carbamate groups were applied to a bicolor fluorescent imaging material through the consecutive reaction with fluorescamine and rhodamine. A various colored fluorescent micropattern (green, red or red-yellow) was observed through the changes of excitation wavelength by using a conforcal microscope.

• 한국가시화정보학회지
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• 제9권2호
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• pp.16-20
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• 2011

This paper presents a fabrication method of microcapsules encapsulating fluorescent nanoparticles sensitive to an organic liquid, which is potentially applicable to the encapsulation of protein, cell and drug. It uses the supra-molecular self-assembly of a block copolymer at the interface of the stable and controllable droplets of water suspended with fluorescent nanoparticles and the polymer solved organic. The size and uniformity of the microcapsules were examined for the various polymer concentrations by using SEM image analysis. The maximum standard deviation of the produced microcapsules of less than 3.5% was obtained from the microcapsules produced from the same conditions. The inclusion of fluorescent nanoparticles was visualized in the fluorescence microscope and by using TEM image. It is shown that this fabrication method can provide the uniform size microcapsules with a higher inclusion.

• Journal of Biosystems Engineering
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• 제24권5호
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• pp.391-398
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• 1999

The spraying status of the electrostatic sprayer was evaluated by processing surface spraying images of the natural leaves. Water solution of the fluorescent material was used as a spray medium. The image of the lights reflected by fluorescent droplets was captured under UV light using a color CCD camera. Coverage rate, particle density, and the size distribution of particles were analyzed from the surface images of leaves under various spraying conditions such as spraying nozzle angle and object distance. Spraying characteristics of the electrostatic sprayer was evaluated in comparison with the conventional one. In a case of electrostatic sprayer, coverage rate and particle density increased by the average of 1.57times and 1.01times respectively under various nozzle angles and distances. The number of particle under the diameter of 50 ${\mu}{\textrm}{m}$ also increased significantly.

• 디자인학연구
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• 제19권4호
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• pp.205-208
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• 2006

본 작품은 jitter의 multiplex기능을 이용한 디지털 아트작품으로 두 가지 영상의 cross concept를 이용한 인터렉티브 영상 설치 작품이다. 평면스크린이 아닌 형광등을 이용하여 특수 제작한 스크린을 통해, 형광등에 비춰지는 영상과 그 틈새로 벽에 비춰지는 두 가지 영상을 보여주게 된다. 실시간으로 카메라에 의해 받아들여진 관객의 모습과 제작해 놓은 두 가지 영상은 jitter의 multiplex기능에 의한 합성과정을 거쳐 형광등 스크린에만, 또는 벽에만 비춰지게 된다. 한 영상이지만 관객의 모습은 벽과 형광등을 오가며 관객을 혼란에 빠트리게 된다. 제작한 영상과 실시간으로 입력되는 관객의 두 가지 모습은 상반, 또는 병치의 느낌으로 관객에게 다가가게 되며 그것은 인간의 이중성을 표현하게 되는 동시에 물리적인 존재공간과 우리가 느끼는 시각적 공간을 구분하여 서로 다른 지배 문법이 있다는 것을 표현하게 된다. 퍼스펙티브와 환경에 의해 왜곡되는 영상재현의 과정을 보여주기 위해 형광등으로 제작한 스크린과 cross concept의 영상을 제작 사용하였다.

• 대한의용생체공학회:의공학회지
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• 제28권2호
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• pp.195-198
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• 2007

In this paper, we introduce a digital cross-polarization and fluorescent color imaging system for quantitative evaluation of skin lesions. We describe the characterization of the imaging systems and the quantitative image analysis methods to show the feasibility for quantitative evaluation of skin lesions. The polarization color image was used to compute erythema and melanin index image which are useful for quantitative evaluation of pigmentation and vascular skin lesions, respectively. The fluorescent color image was used to quantitatively evaluate "sebum" and "vitiligo". In quantitative evaluation of various skin lesions, we confirmed the clinical efficacy of the imaging systems for dermatological applications. Finally, we sure that the imaging systems can be utilized as important assistant tools for the evaluation of skin lesions by providing reproducible quantitative result for widely distributed skin lesions.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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• pp.694-697
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• 2003

In applying LCD to TV application, one of the most significant factors to be improved is image sticking on the moving picture. LCD is different from CRT in the sense that it's continuous passive device, which holds images in entire frame period, while impulse type device generate image in very short time. To reduce image sticking problem related to hold type display mode, we made an experiment to drive LCD like CRT. We made articulate images by turn on-off backlight, and we realized the ratio of Back Light on-off time by adjusting between on time and off time for video signal input during 1 frame (16.7ms). Conventional CCFL (cold cathode fluorescent lamp) cannot follow fast on-off speed, so we evaluated new fluorescent substances of light source to improve residual light characteristic of CCFL. We realized articulate image generation similar to CRT by blinking drive. As a result, reduced image sticking phenomenon was validated by naked eye and response time measurement.

• 융합신호처리학회논문지
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• 제2권4호
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• pp.46-52
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• 2001

방사광을 이용한 형강 X선 CT 이미징의 고속화를 위한 촬상 시스템과 처리 알고리즘을 검토하였다. 본 논문에서 사용된 촬상시스템은 고계수율 영역에서 안정된 동작을 한 전자 시스템으로 불감시간이 약 6%로 감소되고 계측시간의 경우도 1 점 당 3초로 단축되었다. 또한 재구성 알고리즘의 효율화를 증명하였고, 메모리와 계산량을 약 1/100로 감소시켰다. 물리적 phantom으로 그 정량성을 확인하였고, 시험관내의 갑상선의 화상으로부터 요드 분포를 추정하였다. 이러한 결과는 생체내에서 형광 X선 CT 계측의 실현 가능성을 보여준 것이다.

• 한국가시화정보학회지
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• 제2권1호
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• pp.39-45
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• 2004

A time-resolved two-phase PIV system using a single camera has been developed, which introduces a method of image separation into respective phase images, and is applied to freely rising single bubble. Gas bubble, tracer particle and background have different gray intensity ranges on the same image frame when reflection and dispersion in the phase interface are intrinsically eliminated by optical filters and fluorescent particles. Further, the signals of the two phases do not interfere with each other. Gas phase velocities are obtained from the separated bubble image by applying the two-frame PTV. On the other hand, liquid phase velocities are obtained from the tracer particle image by applying the cross-correlation algorithm. As a result, the bubble rises rectilinearly just after it is released from an injector and then has a zigzag motion in the far field. From the trajectory of the bubble, it is found that the period of the zigzag motion is closely related to the vortex shedding although the wavelength of it varies along its movement.

• 한국위성정보통신학회논문지
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• 제7권3호
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• pp.145-148
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• 2012

최근의 TV용 TFT-LCD에서는 동화상에서의 잔상발생을 줄이는 것이 중요한 기술적 요구사항이 되었다. Single-LVDS 신호체계에서 3D를 대응하기 위한 Quad Signal Package 까지 진화하면서 보다 빠른 신호를 정해진 시간안에 처리해야 하는 문제가 발생하고 있으며, 이러한 특성을 구현하기 위해서 잔상효과가 없는 Backlight에 대한 연구가 활발히 진행되고 있다. 본 연구에서는 점멸방식의 Backlight 를 사용하여, 1Frame의 시간안에 이 동작이 가능하게 구현하는 것을 목표로 삼았으며, 광원으로는 기존의 냉음극관램프를 사용하였다. 통상 냉음극관램프는 주 발광파장대를 담당하는 녹색의 잔광시간이 길어서 위와 같은 특성을 구현하기에 어려움이 있었으나, 본 연구에서는 단잔광 특성을 가지는 녹색 및 적색 형광체를 적용한 냉음극관램프를 적용하여, 1Video Frame의 시간안에 점멸동작이 가능한 백라이트를 제작하였으며, 이를 사용하여, 동화상에서 비약적인 잔상 해결 효과를 확인할 수 있었다.