• 한국정보디스플레이학회:학술대회논문집
• /
• 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
• /
• pp.799-802
• /
• 2004

In this paper, the active backlight control technology with data processing algorithm was developed in order to improve image quality for IPS-mode LCD-TV applications. The image blinking problem caused by repeatedly abrupt change of the backlight luminance was solved by algorithms-Fba(Flexible Boundary algorithm) and Cfa(Cumulative Feedback algorithm)-and the optimized number and space of backlight dimming steps based on perception. In the IPS-mode 42" TFT-LCD panel, the dynamic contrast ratio can be more than twice the typical level by means of lower block luminance and higher white luminance. Additionally, Power consumption and LCD temperature was decreased.

• 한국환경보건학회지
• /
• 제28권5호
• /
• pp.22-27
• /
• 2002

The composting practice has been recognized as the most popular way of controlling food waste and many attempt have been made in the field to establish more efficient and economical process. Some of the efforts are mixing cured compost with sawdust as alternative bulking agent, seeding commercially produced microorganism and/or combination of above. However, verification of such efforts is often restricted because of either the lack of engineering consideration on the limitation of composting facility scales. In this study, the effect of mixing materials in food waste composting was investigated by controlling the combination and the mixing ratio of them. When the cured compost was mixed with saw dust. the decomposition of organic material was proven to be more active by observing the compost temperature, the oxygen (O$_2$) consumption, and the cumulative carbon dioxide ($CO_2$) profile. However, the quantity of compost mix-ing seemed not to influence the reaction as long as the minimum required amount was mixed. The feeding of com-mercially produced microorganism had a tendency to prolong the thermophilic stage, which helped to increase the decomposition but it resulted in composting period. Regardless of the composting condition, bacteria and actinomycetes increased in population as the reaction approached to the end. The population of bacteria and actinomycetes were rel-atively higher than those of fungi and yeast throughout the reaction.

• 한국건축시공학회지
• /
• 제16권3호
• /
• pp.211-217
• /
• 2016

본 연구에서는 2015년 가을철 실제 시공중인 고층 아파트를 대상으로 1중 백색 버블시트로 타설된 콘크리트의 표면을 덮어주는 버블시트 피복양생 공법과 표면을 노출한 채로 양생없이 유지하는 표면노출 방법간을 비교하여 소성 및 건조수축균열의 저감정도를 분석하였다. 실험 결과, 버블시트를 시공하였을 경우, 수화열 및 적산온도는 표면노출보다 약간 높았고, 바닥 균열의 갯수, 길이, 최대 균열폭, 균열 면적 모두 현저하게 적은 값이 측정되었다. 따라서 가을철 버블시트를 타설된 콘크리트 표면에 적용 할 경우에는 소성 및 건조수축균열을 획기적으로 방지할 수 있는 효과적인 표면피복 양생공법인 것으로 판단되었다.

• 한국농업기계학회:학술대회논문집
• /
• 한국농업기계학회 2000년도 THE THIRD INTERNATIONAL CONFERENCE ON AGRICULTURAL MACHINERY ENGINEERING. V.III
• /
• pp.777-783
• /
• 2000

Composting by negative aeration is a reasonable proposition to control odor generated during composting process. Cattle manure and rice hulls mixtures were composted in a bin composting system by negative aeration. Continuous(CA) and intermittent(IA) aeration methods were applied to analyze the composting characteristics. The composting temperature and the ammonia emission during composting were investigated according to the aeration methods. The main problem for the negative aeration was the generation of condensate in the suction line of blower. The quantity of condensate was significant for continuous aeration. The aeration method should be modified to escape from the cooling effect of continuous aeration at the initial stage of composting. It took a longer time to finish a composting for intermittent aeration on account of lower aeration. It was concluded that the composting by negative aeration could be accomplished by either continuous or intermittent aeration method if the flow rate would be controlled more efficiently and the water vapor in suction line of blower could be removed effectively. Ammonia emission increased up to maximum value of 675ppm for continuous aeration while 300ppm for intermittent aeration. However, the cumulative value of ammonia emission was larger for intermittent aeration than for continuous aeration.

• 한국잠사곤충학회지
• /
• 제4권
• /
• pp.47-50
• /
• 1965

본 시험은 중장형다각체병이 과연 우리나라에서도 전염하는가를 알기 위하여 실시한 것이다. 그 결과 우리나라에서도 이것이 전염함을 알았기에 이를 보고한다. 1. 여러 가지 인위적 유발처리에 의하여 중장형다각체병이 유발되며 기중에서도 5령 기잠을 향식 적기에 저온처리한 것이 (5$^{\circ}C$, 24시간) 가장 효과적이었다. 2. 추잠기 보통사육잠에서도 해잠병이 발생하였으니 사육중의 모든 악조건의 총화가유인이 되어서 발병한 것이라고 하겠다.

• 한국응용과학기술학회지
• /
• 제28권1호
• /
• pp.57-63
• /
• 2011

Polymer electrolyte membrane fuel cell (PEMFC) performance degrades when hydrogen sulfide ($H_2S$) is present in the fuel hydrogen gas; this is referred to as $H_2S$ poisoning. This paper reveals $H_2S$ poisoning on PEMFC by measuring electrical performance of single cell FC under various operating conditions. The severity of $H_2S$ poisoning depended on $H_2S$ concentration under best operating conditions($65^{\circ}C$ of cell temperature and 100% of anode humidification). $H_2S$ adsorption occured on the surface of catalyst layer on MEA, but not on the gas diffusion layer(GDL) by analyzing SEM/EDX data. In addition, MEA poisoning by $H_2S$ was cumulative but reversible. After poisoning for less than 150 min, performance of PEMFC was recovered up to 80% by just inert nitrogen gas purging.

• 조명전기설비학회논문지
• /
• 제29권3호
• /
• pp.45-53
• /
• 2015

A I-V and P-V characteristic of solar cell is changed to nonlinear by radiation and temperature. Therefore, to use efficiently PV system, operating point of PV system is must operate at maximum power point always. A performance of conventional the PO and the IC method is depend on the step size. So it has weakness which is must select optimal step size. Also, MPPT control applying PI and fuzzy control is not expected satisfactory performance, because of PI controller has fixed gain and fuzzy control has cumulative error by an integral calculus. Therefore, this paper proposes the VS-PO(Variable Stepsize - Perturbation & Observation) MPPT control that is automatically adjusted the step size according to the operating conditions. The VS-PO MPPT method proposed in this paper analyzes control characteristic about condition of radiation and compares with conventional methods. The validity of this paper proves using this results.

• 한국식품과학회지
• /
• 제18권2호
• /
• pp.168-172
• /
• 1986

본 연구는 홍미삼으로부터 홍삼엑기스를 제조할 때 추출용매와 온도 그리고 추출시간의 변화가 추출과정중 원료삼의 팽윤성과 흡수성 그리고 홍삼엑기스의 고형분 수율의 차이를 비교한뒤 이들의 관계를 통계적으로 분석함으로서 추출조건에 따른 이들 성질을 예측코져 하였다. 홍미삼의 팽윤율과 흡수율은 에탄올의 농도가 높을수록 현저히 감소되었으며, 온도의 상승으로 흡수율은 증가되었으나 평형시의 팽윤율에는 영향을 주지않았다. 한편 가용성 물질이 용출율은 에탄올의 농도가 높을수록 감소되어었으며 온도상승에서는 반대로 증가되었다. 또한 각 추출조건에서 추출시간에 따른 팽윤율과 흡수율 그리고 용출율은 높은 상관관계를 갖는 대수함수적 관계를 가지고 있었다. 따라서 이들의 관계식으로부터 주어진 에탄올의 농도와 추출시간에서의 이들의 성질을 예측할 수 있었다.

• 한국응용과학기술학회지
• /
• 제28권4호
• /
• pp.497-501
• /
• 2011

Polymer electrolyte membrane fuel cell (PEMFC) performance degrade when sulfur dioxide is present in the fuel hydrogen gas, this is referred as $SO_2$ poisoning. This paper reveals $SO_2$ poisoning on PEMFC cathode part by measuring electrical performance of single cell under 1 ppm and 5 ppm on $SO_2$ gas operating. The security of $SO_2$ poisoning depended on $SO_2$ concentration under the best operating conditions($65^{\circ}C$ of cell temperature and 100% of relative humidity between anode and cathode). $SO_2$ adsorption occured on the surface of catalyst layer on membrane electrode assembly (MEA), In addition, MEA poisoning by $SO_2$ was cumulative but reversible. After poisoning within 5 ppm $SO_2$ for 1hr, the electrical performance of PEMFC was found to recover up to about 93% by cyclic voltametry scan.

• 전자공학회논문지D
• /
• 제34D권5호
• /
• pp.32-44
• /
• 1997

A three-dimensional (3D) full-dynamic damage model for ion implantation in crystalline silicon was proposed to calculate more accurately point defect distributions and ion-implanted concentration profiles during ion implantation process. The developed model was based on the physical monte carlo approach. This model was applied to simulate B and BF2 implantation. We compared our results for damage distributions with those of the analytical kinchin-pease approach. In our result, the point defect distributions obtained by our new model are less than those of kinchin-pease approach, and the vacancy distributions differ from the interstitial distributions. The vacancy concentrations are higher than the interstitial ones before 0.8 . Rp to the silicon surface, and after the 0.8 . Rp to the silicon bulk, the interstitial concentrations are revesrsely higher than the vacancy ones.The fully-dynamic damage model for the accumulative damage during ion implantation follows all of the trajectories of both ions and recoiled silicons and, concurrently, the cumulative damage effect on the ions and the recoiled silicons are considered dynamically by introducing the distributon probability of the point defect. In addition, the self-annealing effect of the vacancy-interstitial recombination during ion implantation at room temperature is considered, which resulted in the saturation level for the damage distribution.