• Journal of IKEEE
• /
• v.22 no.3
• /
• pp.585-589
• /
• 2018

Consumer demand for high quality image/video services led to growing trend in image quality enhancement study. Therefore, recent years was a period of substantial progress in this research field. Through careful observation of the image quality after processing by image enhancement algorithms, we perceived that the dark region in the image usually suffered loss of contrast to a certain extent. In this paper, the low-light stretch preprocessing algorithm is, hence, proposed to resolve the aforementioned issue. The proposed approach is evaluated qualitatively and quantitatively against the well-known histogram equalization and Photoshop curve adjustment. The evaluation results validate the efficiency and superiority of the low-light stretch over the benchmarking methods. In addition, we also propose the 255MHz-capable hardware implementation to ease the process of incorporating low-light stretch into real-time imaging systems, such as aerial surveillance and monitoring with drones and driving aiding systems.

• Ocean and Polar Research
• /
• v.25 no.4
• /
• pp.617-623
• /
• 2003

Organisms living in the Arctic and Antarctic regions are exposed to strong constraints, of which temperature is a driving factor. Evolution has led to special adaptations, some with important implications at the biochemical, physiological, and molecular levels. The northern and southern polar oceans have very different characteristics. Tectonic and oceanographic events have played a key role in delimiting the two polar ecosystems and influencing evolution. Antarctica has been isolated and cold longer than the Arctic; its ice sheet developed at least 10 million years earlier. As an intermediate system, the Arctic is a connection between the more extreme, simpler Antarctic system and the very complex temperate and tropical systems. By studying the molecular bases of cold adaptation in polar fish, and taking advantage of the information available on hemoglobin structure and function, we analysed the evolutionary history of the ${\alpha}\;and\;{\beta}globins$ of Antarctic and Arctic hemoglobin using the molecular clock hypothesis as a basis for reconstructing the phylogenetic relationships among species.

• Journal of Advanced Marine Engineering and Technology
• /
• v.33 no.5
• /
• pp.662-671
• /
• 2009

In this paper, a robot was developed for in-pipe cleaning and inspecting a large number of circular in-pipes of sea plants, ships, and buildings. A pressure generation mechanism was devised to inspect circular in-pipes with different diameters and to move up and down slant or perpendicular slopes in-pipes. For inspection of the dark inner side of the pipe, a light system using LED which dissipats small electricity was developed. Also, a design method was analyzed to decide the capacity of driving motor for the robot when the mass and maximum velocity of the robot are identified. The robot developed based on the design specification, was tested to verify the performance of the pressure generation mechanism. In addition, a control system was developed for the test.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2002.10a
• /
• pp.562-565
• /
• 2002

Recent technologic innovations have created possibilities for restorative dentistry, such as computer-aided design and computer-aided manufacturing. This article presents a CAD process that has been developed for the fabrication of dental restorations. This process uses a 4-axes driving mechanism and an improved optical displacement sensor, successfully applied in other industries. In optical displacement sensor, the light beam emitted from the LED is converged through the light source lenses and thrown on the object to be detected. When the light beam is reflected from the object, however, it is diffused. The diffused light beam is converged again by the receiver lenses and cast on the optical position detector element as a small spot.

• Laser Solutions
• /
• v.17 no.1
• /
• pp.17-21
• /
• 2014

Head up display is in increasing demand for advanced devices in the modern luxury vehicles. It helps drivers focus on driving environment on the road. While HUD technology with LED has advanced, the brightness in daylight can be still an issue to be resolved. Laser light source is a possible solution to overcome the brightness problem and optimal optics design is required for the best performance. Sample design of optics is proposed and detail procedure of lens design evaluation is presented in this paper. The results were characterized by using a ray tracing method and qualitative analysis for spot and DEE is also presented. The overall error or image distortion remained in the target range of $25{\mu}m$ and the simulated image demonstrated possible use in the automotive applications.

• Journal of the Semiconductor & Display Technology
• /
• v.4 no.2 s.11
• /
• pp.21-24
• /
• 2005

Ink-jetting characteristics of pulse width and pulse amplitude for a piezoelectric ink jet printer driver have been mapped with various polymer EL ink. In this study, the jetting characteristics have been classified into 4 regime; no Jetting, unstable jetting, stable jetting, and spraying, and the importance of fluid viscosity on the scope of the stable jetting regime has been emphasized. The relation between jetting speed and the width and amplitude of driving signal has also been investigated and the effect of the speed on the jetting characteristics has been discussed.

• Journal of Industrial Technology
• /
• v.27 no.B
• /
• pp.125-128
• /
• 2007

This paper presents Spectral-Domain optical measurement system using self-fabricated CCD sensor driver. The light source is a high brightness white LED and the detector is a 2048 array typed CCD image sensor. I have fabricated the CCD sensor driver to generate four pulse signals, which are the CCD-driving pulses. Using this Spectral Domain optical measurement system, the distance value between the reference mirror and the sample mirror can be obtained successfully.

• Proceedings of the KIEE Conference
• /
• 2003.07c
• /
• pp.1710-1712
• /
• 2003

This paper analyzes the effects of various operating voltages on the luminous efficacy of high flux RGB LEDs. At first, their equivalent diode model are established from measurements of the V-I characteristics. Operating voltages of three types are applied to a simple LED circuit: DC, square-wave, and full-wave-rectified sine wave. As the result, DC voltage driving gives the hightest efficiency, but invokes much greater variation in the luminous flux and more shift in the peak wavelength.

• Proceedings of the KIPE Conference
• /
• 2012.07a
• /
• pp.443-444
• /
• 2012

최근 각광받고 있는 반도체 발광 소자를 이용한 고체 상태 광원(Solid State Lighting)은 기존 광원에 비해 고효율이어서 에너지 절약적 측면에서 대두되고 있다. 점광원인 LED에 비해 면광원인 OLED는 두께를 얇게 구현할 수 있고, 다양한 모양으로 광원의 구현이 가능하다. 따라서, 본 논문에서는 효율적인 OLED 조명 구동을 위해 넓은 입력전압 범위를 지니는 Buck-Boost 컨버터를 제안한다.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2022.11a
• /
• pp.842-844
• /
• 2022

각종 유해조수로에 의한 피해가 농가에서 발생하고 있다. 이를 해결하기 위해 기존에 Drone을 이용한 유해조수 퇴치연구가 있엇지만 시간의 제약과 법적인 규제로부터 발생되는 문제점이 발견되어 이를 해결하기 위해 Drone을 Caterpillar 구동형 모바일 로봇으로 대체하였고, 자율주행 기능을 추가하였다. 텐서플로우 객체 검출 딥러닝을 적용하여 유해조수를 학습 및 파악한다. 이 후 유해조수 인식 시 사용자에게 실시간 알림 서비스 및 실시간 스트리밍을 제공하고, 유해조수 퇴치 로봇에 장착된 스피커와 Neo Pixel LED을 이용하여 유해조수의 시각과 청각을 자극하여 퇴치한다. ROS, SLAM과 Object Following을 이용하여 자율주행 로봇을 제어하고 객체를 추적한다.