• Photonics industry news
• /
• s.16
• /
• pp.46-53
• /
• 2003

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2003.06a
• /
• pp.386-389
• /
• 2003

Recent issues in Optical Disk Drive (ODD) are focused on small size. Blu-ray Disk (BD), using blue laser (405nm wavelength) and high NA (0.85) objective lens. can store 25Gbyte on a conventional 12cm optical disk. Small Form Factor Optical (SFFO) drive uses 3cm disk which can store 1.5Gbyte on a disk. This kind of Small Form Factot Optical (SFFO) drive correspond to PCMCIA type memory (Compact Flash or Micro Drive). Preferably, Optical Disk has relatively low cost of the storage media per Byte rather than PCMCIA type memory. To make Small Form Factor Optical (SFFO) drive. optical pickup and its component must be miniaturized. Miniaturization of the component needs new concept of Optical Pickup. This paper is focused on two main subjects. One is Objective Lens design which can be manufactured on a wafer, and the other is optical path design of the pickup which has 2mm thickness.

• Proceedings of the Optical Society of Korea Conference
• /
• 2003.02a
• /
• pp.248-249
• /
• 2003

아조벤젠 고분자는 광 정보저장 및 광 스위치 소자 등의 응용가능성 때문에 많은 연구가 진행되어왔다. 이것은 바로 아조 분자가 가지고 있는 두 이성체 간의 광 이성화 과정에 의한 아조 분자의 정렬과 이 때문에 야기되는 광 유도 anisotropy가 생기는 특성 때문이다. 이와 더불에 아조 분자 필름에 빛을 쪼여 주었을 때 표면에 주기적인 부조 격자(SRG)가 형성됨이 보고 된 이후에 광 정보 저장은 물론 액정의 anchoring 이나 phase mask로의 응용, 특히 photonic band gap(PBG) 효과를 기대 할 수 있는 주기구조 형성에의 응용성 때문에 더욱 관심이 집중되고 있다. (중략)

• Proceedings of the KIPE Conference
• /
• 2014.07a
• /
• pp.470-471
• /
• 2014

본 논문은 에너지 저장장치를 태양광 발전 시스템에 적용시에, 필요한 충전 균형회로를 전력조절기와 통합시키는 방법에 관한 것이다. 기존의 방식은 전력조절기와 별도로 충전 균형회로를 이용하게 되는데, 이는 복잡한 구성을 필요로 하고, 단가 상승의 원인이 된다. 본 논문에서는 태양광 전력변환 시스템 제작 단가를 낮추기 위해 태양광 모듈을 저장장치와 함께 직렬형 구조로 구성한 뒤 적절히 결선하여, 태양광 전력조절기를 셀 밸런싱 회로로 사용하는 방법을 제안하며, 이를 48W 하드웨어 제작 및 실험을 통해 검증하였다.

• Journal of the Korean Society for Precision Engineering
• /
• v.18 no.4
• /
• pp.46-54
• /
• 2001

Technology of data storage device has developed noticeably as demands and needs of new media increase, Huge data can be conveniently handled using removable type optical disk. In the present paper, the trend and current issue of development for optical disk media are introduced. Standardization of next generation optical disk media, technology of recording and reading, and applications of magneto-optical devices are also discussed. Finally, a methodology of process optimization for design and fabrication of high density optical disk substrate is proposed.

• Korean Journal of Weed Science
• /
• v.7 no.2
• /
• pp.130-138
• /
• 1987

The effects of light and storage conditions on the germination of Oenothera lamarckiana were investigated. Germination was induced by red light, but inhibited by green, blue or infrared. No germination occurred in the dark. Radicle was more photosensitive than other parts of the seed. The rate of germination was proportional to increase in Light intensity ranging from 10 to 3000 Lux. Photosensitivity occurred 6 hrs after water imbibition of air-dried seeds. Maximum photosensitivity was detected 1-2 days after seeding under the light condition at 300 Lux. Germination was almost completed 3 days after seeding. When seeds stored in the chilling and wetting condition were kept at constant temperature in the dark, they germinated well. Air-dried seeds, however, didn't germinate. Whereas, the seeds which kept at alternating temperature had the tendency that seeds stored at room temperature (25$^{\circ}C$) germinated better than those stored at low temperature (4$^{\circ}C$).

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2004.05a
• /
• pp.60-60
• /
• 2004

광디스크 미디어 저장기기에 있어서 음악과 영상을 재생하는 광디스크 플레이어의 기구부품 중 턴테이블은 디스크를 장착, 고정하여 디스크에 기록된 신호를 재생케 하는 광디스크 메커니즘의 중요기능 부품이다. 특히 별도의 클램퍼 없이 턴테이블에 부설된 탄지력만으로 디스크를 장착, 고정하는 슬림형 플레이어에서 스핀들 모터의 회전 시 턴테이블에 장학된 광디스크의 슬립은 재생에러를 야기한다. 스피닝 회전속도가 증가할수록 디스크의 슬립을 방지하기 위해서는 디스크와 턴테이블의 증가된 마찰력이 요구된다.(중략)

• Proceedings of the Optical Society of Korea Conference
• /
• 2003.02a
• /
• pp.178-179
• /
• 2003

단일기본모드 수직공진표면광레이저(VCSELs)는 광네트워크, 광연결, 광저장 및 레이저 프린팅 등 다양한 분야에 응용이 가능한 소자로서 많은 관심과 연구가 증대되고 있다. 일반적으로 VCSELs은 공간홀버닝(spatial hole burning)과 열 렌즈효과(thermal lensing)로 인하여 단일기본모드로 동작하기가 쉽지 않다. 지금까지 여러 가지 연구가 진행되고 있는데 대표적인 예로서 VCSEL의 공진기를 길게 하거나 출력경 표면을 정교하게 식각하는 방법, 그리고 이온 주입구경과 산화막을 함께 사용한 것들이 있다. (중략)

• Journal of Satellite, Information and Communications
• /
• v.11 no.2
• /
• pp.42-47
• /
• 2016

Due to advances such as photovoltaic power generation and energy storage system, energy self-consumption smart home system in which energy management system is built and energy is generated in house has been actively researched. In particular, due to the instability of the grid after the Fukushima nuclear accident, home system in which generating electricity from photovoltaic, storing and using it in energy storage system was commercialized in Japan. While subsidizing renewable energy projects through a combination of solar and energy storage systems in North America and Europe has expanded home installation. In this paper, we describe development of self-consumption smart home system which is connecting photovoltaic system and energy storage system in home area network and operating it based on real-time price. We implemented automated self-consumption home in which optimizing the use of energy from the power grid with minimal user's intervention.

• Food Science and Preservation
• /
• v.8 no.4
• /
• pp.362-366
• /
• 2001

This study was conducted to reduce degradation of marketability by the rot and discolor of onion bulbs under room temperature from 1977 to 1998. Allium cepa cv. Changnyungdeago, late strain, was used for the test at the storage condition of non-shading, 55% and 95% shadings. The results obtained are as follows: The mean temperature was maintained lowly 1.0∼2.9$\^{C}$ in 55% and 2.0∼3.8$\^{C}$ in 95% shadings in contrast to nun-shading, but the relative humidity was a tittle higher in high shading than other shading condition. The illumination and color density maintained lowly in high shading. After 21 days of storage, the rate of discolored onion bulbs was significantly higher in non-shading(90.0%) than 55%(35.7%) and 95%(13.3%) shadings. The rotting rate by the end of August was a little decreased at 55%(25.4%) and 95% shadings(26.5%) in contrast to non-shading(28.9%), and total weight loss was maintained lowly in high shading.