• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2008년도 추계학술대회 논문집 전력기술부문
• /
• pp.19-21
• /
• 2008

Renewable energy resources such as wind, wave, solar, micro hydro, tidal and biomass etc. are becoming importance stage by stage because of considering effect of the environment. Solar energy is one of the most successful sources of renewable energy for the production of electrical energy following wind energy. And, the solar/photovoltaic cell generators can not make two-state model as conventional generators, but should be modeled as multi-state model due to solar radiation random variation. The method of obtaining reliability evaluation index of solar cell generators is different from the conventional generators. This paper presents a basic study on reliability evaluation of power system considering solar cell generators with multi-states.

• 한국정보디스플레이학회:학술대회논문집
• /
• 한국정보디스플레이학회 2003년도 International Meeting on Information Display
• /
• pp.555-558
• /
• 2003

The bistability in a chiral-splay nematic liquid crystal cell, which is obtained by adding a chiral additive to a splay cell, is proposed. In this paper, we describe a new horizontal way of switching between the two states of the bistable chiral-splay cell, one state being characterized by a non-twisted director field with splay, the second state showing a director-field with $180^{\circ}C$ twist.

• 반도체디스플레이기술학회지
• /
• 제5권1호
• /
• pp.17-20
• /
• 2006

This paper presents of a new type of memory cell that could potentially replace both DRAM and flash memory. The proposed device cell operates by sensing the state of about 1,000 electrons trapped between unique insulating barriers in the channel region of the upper transistor. These electrons are controlled by a side gate on the transistor, and their state in turn controls the gate of the larger transistor, providing signal gain within the memory cell. It becomes faster and more reliable memory with lower operation voltage. Moreover, the use of a multiple tunnel junction (MTJ) fur the vertical transistor can significantly improve the data retention and operation speed.

• 한국전기전자재료학회논문지
• /
• 제16권10호
• /
• pp.908-913
• /
• 2003

We have performed computer simulation to obtain electro-optic characteristics of reflective hybrid aligned nematic liquid crystal displays (LCDs) driven by fringe field. The results show that the optimal retardation value (dΔn) of the cell is 0.289 ${\mu}$m, which allows for the cell to have a practical cell gap of larger than 3 ${\mu}$m when manufacturing. A reflectance of the dark state is only 0.114 % for an incident light 550 nm. At this condition, the light efficiency of white state reaches 92.7 %. The display with optimized cell parameters shows that the contrast ratio greater than 5 exists over 600 of polar angle in all directions and lower driving voltage than that of fringe-field driven homogeneously aligned reflective LCD.

• Journal of the Optical Society of Korea
• /
• 제13권3호
• /
• pp.335-340
• /
• 2009

Ultrashort pulse laser drilling of polycarbonate track-etched membrane (pTEM) material was used to fabricate a mouse embryo cell trapping device. Holes with a diameter of $2{\mu}m$ to $5{\mu}m$ were fabricated on a $10{\mu}m$ thick membrane using a femtosecond laser with a 150 fs pulse width and 775 nm wavelength and multiple-pulse irradiation. In cell trapping tests, the overall cell occupancy of the machined holes in the fabricated pTEM was found to be more than 80%. The results of a single pulse and multiple pulse irradiation were compared in terms of the surface quality. It was generally found that a single pulse with high energy was less desirable than irradiation with multiple pulses of lower energy.

• 한국정보디스플레이학회:학술대회논문집
• /
• 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
• /
• pp.1130-1132
• /
• 2009

We propose a novel way for enhancement of efficiency on a quasi solid-state dye-sensitized solar cell (DSSC). It contained gel type electrolyte mixing the liquid crystal (LC) of specific concentration and applied voltage for alignment of the LC. Aligned LC is supported charge transfer inside electrolyte and efficiency is increased in DSSC. We made a quasi solid-state DSSC which applied DC voltage or not and have measured the power conversion efficiency (PCE) and the fill factor. From measurement, we obtain high performances in case of cell applied voltage compare to reference cell.

• 한국정보디스플레이학회:학술대회논문집
• /
• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
• /
• pp.954-957
• /
• 2007

We analyzed conditions for fabricating zero-bias polymer-stabilized liquid crystal (PSLC) pi cells. A high curing voltage and a very low curing intensity are effective in fabricating the cell with a high bright state, a low dark state and therefore a steep T-V curve. However, the response time of the cell is slow. Finally, a dual-frequency PSLC pi cell with fast response time is developed. The obtained result reveals that the dual-frequency PSLC pi cell has a fast response of under 1ms.

• Molecules and Cells
• /
• 제27권2호
• /
• pp.135-142
• /
• 2009

The centrosome, an organelle comprising centrioles and associated pericentriolar material, is the major microtubule organizing center in animal cells. For the cell to form a bipolar mitotic spindle and ensure proper chromosome segregation at the end of each cell cycle, it is paramount that the cell contains two and only two centrosomes. Because the number of centrosomes in the cell is determined by the number of centrioles, cells have evolved elaborate mechanisms to control centriole biogenesis and to tightly coordinate this process with DNA replication. Here we review key proteins involved in centriole assembly, compare two major modes of centriole biogenesis, and discuss the mechanisms that ensure stringency of centriole number.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2007년도 추계학술대회 논문집
• /
• pp.3-4
• /
• 2007

Many electrochemical power devices such as solid state batteries and solid oxide fuel cell have been studied and developed for solving energy and environmental problems. Fuel cell is a modular, high efficient and environmentally energy conversion device, it has become a promising option to replace the conventional fossil fuel based electric power plants. This paper offers some new perspectives on fuel cell development and commercialization which come from the broad consideration of the commercialization efforts of the entire fuel cell industry.

• 진공이야기
• /
• 제1권4호
• /
• pp.10-13
• /
• 2014

Since the development of 9.7% efficient long-term stable solid state perovskite solar cell in 2012, intensive study on perovskite solar cell has been performed. As a result, power conversion efficiency (PCE) has reached 20.1%. In-dept study on perovskite light absorber enabled understanding of origin of superb photovoltaic performance of perovskite solar cell. In this article, historical evolutions of perovskite solar cell along with key physical properties enabling high PCE are presented. Several important results for development of high efficiency perovskite solar cell are introduced. Finally, in-present research issues and future direction for solving these issues are discussed.