• Proceedings of the KIPE Conference
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• 2016.07a
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• pp.331-332
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• 2016

본 논문에서는 PWM 슬루율을 제한하기 위한 LC 필터 설계를 제안한다. 기존의 연구에서는 PWM 입력전압과 필터링된 출력 전압에 대한 주파수 분석을 통해 출력단에 나타나는 슬루율을 제한하였다. 하지만 이러한 분석은 순시 출력 슬루율을 정량적으로 분석하기 어렵다. 본 논문에서는 LC필터의 출력 슬루율을 시간 영역에서 분석하고, 이를 제한하는 LC 필터의 정량적인 설계법을 제시한다.

• 한국정보디스플레이학회:학술대회논문집
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• 2004.08a
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• pp.479-482
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• 2004

We report a method for simultaneous measurements of cell gap, twist angle, birefringence dispersion of liquid crystal (LC) material and alignment directions in filled reflective LC cells. The method is based on spectral measurements of the LC cell reflectivity for three orientations ($0^{\circ},45^{\circ},90^{\circ}$) of the exit polarizer and may be applied for LC cells with low and high gaps.

• 한국정보디스플레이학회:학술대회논문집
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• 2004.08a
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• pp.30-33
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• 2004

Sharp has developed industry's largest high-definition LC TV, Aquos LC-45GDI. In this paper, we discuss its 10-bit signal processing as one important enabler of its excellent picture quality. Utilizing 10 bits signal processing, in combination with full-spec High-Definition panel and "Intelligent Environment Illumination Sensor", we have succeeded to realize a beautiful gigantic LC TV.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07a
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• pp.755-758
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• 2005

The mechanism responsible for liquid crystal (LC) alignment on solid substrates treated with mechanical rubbing or polarized UV is not understood. The results of x-ray reflectivity study of LC alignment on a large number of different alignment layers show that the anisotropy in the surface roughness of the substrate completely determines the LC alignment. The anchoring energy depends on the degree of roughness anisotropy and chemical interactions between the substrate and LC molecules.

• Journal of Information Display
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• v.2 no.4
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• pp.19-22
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• 2001

In this paper, we describe the electro-optic effects of photonic crystals made of a synthetic opal filled with a nematic liquid crystal(LC). By applying an external electric field, a shift in the Bragg reflection peak position(stop band) and a field-induced change in its peak reflectivity are observed. These significant surface alignment effects of the opal-LC composite are discussed in a similar manner for Freederick-type transitions of LC within a confined geometry in the presence of external fields.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2002.05a
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• pp.121-125
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• 2002

이동통신기기 등의 고주파용 LTCC(Low Temperature Co-fired Ceramic) LC filter의 소결결에 있어 기존의 소결공정인 전기로 소결공정과 microwave를 이용한 소결공정을 이용하여 소결하였을때 LC filter의 수축율과 무게감소, 그에 따른 밀도의 변화, SEM을 이용한 표면형상 분석을 통해 급속가열을 통한 공정시간의 단축, 낮은 에너지 소비로 인한 제조단가의 절감, 균일한 가열로 인한 소결온도의 저하 등의 장점을 갖는 microwave sintering을 적용할 수 있는 가능성을 제시하였다.

• The Korean Journal of Pesticide Science
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• v.17 no.4
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• pp.363-370
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• 2013

Susceptibility of each developmental stage of Phthorimaea operculella (Lepidoptera: Gelechiidae) were investigated using 16 insecticides which are available in the market in Korea. For the eggs and pupae, only spinosad showed a 71.1% inhibition rate for egg hatchability and a 66.7% inhibition rate for emergence. For the 3rd instar larvae, the feeding toxicities were over 90% for fenitrothion ($LC_{50}$ 336.6 ppm), esfenvalerate ($LC_{50}$ 8.6 ppm), ethofenprox ($LC_{50}$ 35.7 ppm), and emamectin benzoate ($LC_{50}$ 0.05 ppm). Furthermore, the contact toxicities were over 90% for esfenvalerate ($LC_{50}$ 0.87 ppm), ethofenprox ($LC_{50}$ 16.5 ppm), emamectin benzoate ($LC_{50}$ 0.53 ppm), and spinosad ($LC_{50}$ 2.48 ppm) at the recommended concentrations. Deltamethrin and spinosad yielded 100% mortality for adult P. operculella 48 h after treatment. The adult female fecundity was inhibited by deltamethrin, esfenvalerate, emamectin benzoate, spinosad and dinotefuran, which were significantly different from the control. The adult longevities (7.3-8.3 days) were reduced by approximately 1-2 days compared with the control (9.3 day). The emamectin benzoate maintained 100% insecticidal activity 14 days after treatment and ethofenprox maintained over 90% activity 7 days after treatment.

• The Korean Journal of Pesticide Science
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• v.4 no.2
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• pp.56-62
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• 2000

Effects of sublethal dose of imidacloprid on biological characteristics, such as longevity, fecundity and excretions from brown planthopper (BPH) and its repellency to imidacloprid were examined. Topical application of imidacloprid to BPH at the dose of $LD_{10}$ and $LD_{30}$ (These values were determined at 48 hours after topical application of imidacloprid) was remarkably increased the mortality from 3 days after application and showed over 90% mortality on 4 days after application. Topical application of imidacloprid at dose of $LD_{10}$ (16 days) showed no difference compared to the control (16.9 days) in the longevity, while application of $LD_{30}$ was reduced the longevity of BPH to 13.5 days. Application of sublethal dose of imidacloprid to BPH adults reduced the number of eggs laid per day and for adult stage, and the hatchability of their eggs. By root zone application at the dose of $LC_{30}$, 50% longevity and 40% fecundity was reduced respectively, but showed no effect on number of eggs laid per day. The day on which BPH laid 50 % of eggs in number were 7.6 days at the $LC_{10}$ and 5.9 days the of $LC_{30}$ respectively. Hatchabilities of the groups treated with imidacloprid were lower than that of the control. Topical application to BPH at the dose of $LD_{10}$ did not reduce the amount of excretes, but application at the dose of $LD_{30}$ was reduced 26.5% of excretion compared to the control. Leaf dipping into the solution of concentration of $LC_{10}$ and $LC_{30}$ was reduced 96.4% and 98.0% of excretion, respectively. And root zone treatment at the concentration of $LC_{10}$ and $LC_{30}$ reduced 79.5% and 96.6% of excretion, respectively. Repellency rates of BPH to imidacloprid were 20% regardless of the dose of application.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.2
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• pp.182-187
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• 2013

This study was conducted to examine the effect of calcium extracted from salted anchovy (Engraulis japonicus) on the calcium metabolism of rats. Sprague-Dawley male rats were fed low-calcium diets (0.15%) for 2 weeks after the adjustment period. Rats were divided into five groups and were fed experimental diet for four weeks. Experimental diets were low calcium (LC, 0.15% $CaCO_3$), 0.5% $CaCO_3$ (CC), seaweed calcium (SC), calcium lactate (LC), anchovy calcium (AC). The low-calcium diet group (LC) showed the lowest weight gain and had no differences among the groups with adequate calcium intake. Calcium retention was lowest in the LC group and higher in the CL, SC, AC groups than in SC groups. Serum alkaline phosphatase (ALP) level was highest in LC group, and significantly low in the CC and AC groups (p<0.05). Parathyroid hormone and osteocalcin levels showed no differences among experimental groups. The urine deoxypyridinoline (DPD) level was lower in AC and CC groups compared to the LC group (p<0.05). The dry weight of the femur showed no significant differences among normal calcium groups. The bone mineral density of the femur in AC and CC group were significantly higher than the LC group (p<0.05). From these results, calcium extracted from salted anchovy can be useful as a calcium supplement comparable with calcium carbonate.

• Journal of The Korean Society of Grassland and Forage Science
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• v.25 no.4
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• pp.259-266
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• 2005

The objective of this study was to determine which mixture types are suitable for maintaining grazing pasture at alpine area. The mixtures types were evaluated by the botanical composition and dry matter (DM) of forage. The experiment was carried out on the grazing pasture at Daekwanryeong area (altitude ; 840m) from 1991 to 1993. Treatments were composed of seven mixture types made of both different components and amounts of sowing. The components of each mixture were Orchardgrass (OG), Tall fescue (TF), Timothy (TI). Kentucky bluegrass (KBG), Reed cannarygrass (RCG), Red clover (RC) and Ladino clove. (LC). The seeding .ate of OG, TF, TI, KBG and LC in control(C) was 18:9:8:3:2 kg/ha, respectively and those of treatments of T1 (OG:TF:KBG:LC), T2 (OG:TF:KBG:RC), T3 (OG:TI:KBG:LC), T4 (OG:TF:KBG:LC), T5 (OG:TI:KBG:LC) and T6 (OG:RCG:KBG:LC) were 24:8:2:2, 24:8:2:2, 26:8:2:2, 8:28:2:2, 5:24:2:2 and 8:26:2:2 kg/ha, in seeding rate. respectively. The plant heights of mixtures in 1991, 1992 and 1993 were 33, 37, and 33 cm on average of before and after grazing, respectively. The 12cm of stubble height was left after grazing during 3 years which can result in the reduction of forage intake and utilization. This result indicates the grazing period will be needed to adjust. The proportions of TI, OG, KBG and LC in mixtures were increased constantly, and the proportions of weeds and bare lands were little. The T5, in which the smaller amounts of seeds were sown, is considered as proper mixture type for Alpine pasture. The DM yield tended to increase with the increased grazing period, and the highest DM yield was occurred in 1993. No significant difference among treatments was observed for the DM yield, however the 75 was highest (9,344 kg/ha) in the DM yields which is $5.7\%$ greater than the C (8,840 kg/ha). This result indicates that T5 (OG:TI:KBG:LC : 8:24:2:2 kg/ha) is considered to be proper mixture type at alpine pasture considering the botanical composition and forage yield.