• Journal of the Korean Chemical Society
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• v.45 no.1
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• pp.40-44
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• 2001

Benomyl, one of the known endocrine disrupting chemicals, was analyzed to understand the its fate in water. Benomyl analysis process in water sample include the following sequential steps. Hydrolysis of benomyl into carbendazim, solvent extraction, concentration, and the concentration of final carbendazim solution was determined by LC/MS (TOF). Recoveries of the spiked samples were good with the range of 80.6 to 118.6% and the MDL was 1,600 times lower than that of LC/UVD method. The use of LC/MS (TOF) successfully eliminated the positive error incurred by interferencing materials in the matrix.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.17 no.3
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• pp.305-310
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• 2004

We have studied the optimal phase retardation value of a homogeneously aligned liquid crystal (LC) driven by fringe-field when using the LC with positive dielectric anisotropy. In general, the transmittance of a homogeneous aligned LC cell under crossed polarizer is maximum when a twist angle of LC by in-plane rotation is 45$^{\circ}$ with polarizer and the cell retardation becomes λ/2. However, the device using the LC with positive dielectric anisotropy does not follow this since the degree of rotation of the LC is dependent on electrode position and in addition the LCs tilt up along the fringe-field. At the center of common and pixel electrode, the LC is most twisted around a middle position of a cell whereas at the edge position of pixel electrode, the LC is most twisted near bottom surface of a cell. Consequently, the optimal phase retardation of the device becomes much larger than λ/2 and the transmittance can be described using the combination of the in-plane switching and twisted nematic mode.

• The Transactions of the Korean Institute of Power Electronics
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• v.20 no.3
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• pp.239-246
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• 2015

A novel control method of a three-phase PWM inverter with LC filter is proposed. The transfer function of LC filter is the same as that of second-order low pass filter(LPF), which has a zero damping ratio. A simple method of implementing second-order LPF with damping ratio is to add a resistor in an LC circuit. However, in a real power system, adopting damping resistors is impractical because it results in losses proportional to the square of the current flowing through the resistors. Instead of inserting resistors, the proposed control strategy utilizes the measured capacitor voltages to control the oscillation of LC circuit. The overall transfer function of the proposed method is the same as a second-order LPF, and its damping ratio is controllable via control variables. The current controller can have overshoots caused by LC filter. Improved current controller is implemented by an equivalent second-order of LC filter. A 7.5 kVA PWM converter and a PWM inverter with a 5.5 kW induction motor are set up to verify the proposed control algorithm. Test waveforms are also presented to verify the proposed LC filter control algorithm.

• BMB Reports
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• v.29 no.5
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• pp.393-397
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• 1996

Sprague-Dawley male rats (150 g) were chronically treated with 5 v/v % ethanol admixed with nutritionally complete liquid diet and fed ad libitum for 3 weeks. Controls were pair fed with the isocaloric sucrose liquid diet. One half of each group was exposed to cold stress at $4^{\circ}C$ either for 24 h (for determination of mRNA by in situ hybridization) or for 48 h (for determination of enzyme activity). Chronic ethanol treatment (ethanol) did not affect tyrosine hydroxylase (TH) mRNA level in locus coeruleus (LC) of brain and adrenal medulla (AM) compared to controls. Cold stress showed strong increase of TH mRNA level in LC and AM compared to controls. Pretreated ethanol reduced the increased TH mRNA level by cold stress in LC and AM. Ethanol did not affect TH activity in LC and adrenal glands (adrenals). Cold stress increased TH activity in LC but not in adrenals. Pretreated ethanol did not reduce the increased TH activity by cold stress in LC but this result was not shown in adrenals. It is suggested that ethanol does not affect the message level and enzyme protein level for TH in LC and AM in normal rat. It is also hypothesized that pretreated ethanol reduces the magnitude of acute cold stress response, that is induction of TH mRNA in LC and AM, and does not reduce the increased TH enzyme protein that is also acute cold stress response in LC.

• The Journal of the Korea Contents Association
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• v.7 no.3
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• pp.50-59
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• 2007

IP address lookup is one of the most important and complex functions in the router. In this paper, we propose an improved technique of LC-trie to increase the performance of IP address lookup in the high performance router. We effectively apply the prefix pruning method, which is used for the compression of the forwarding table in TCAM((Ternary Content Addressable Memory), to the LC-trie. This technique can decrease the number of memory accesses and upgrade the lookup speed. Moreover, through the real forwarding table and the real traffic distribution, we evaluate the performance of our scheme in terms of the lookup time and the number of memory access, comparing with that of the previous LC-trie.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08a
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• pp.39-42
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• 2007

Since the scalability of OLED process is crucial factor for large-sized TV manufacturing, various technologies are reviewed based on the published information. Despite of recent technology advancement enabling high color purity, large-sized AMOLED, a lot of problems to solve still exist to enter the large-sized display market. Here, Samsung will discuss what has to be concerned for large panel and how far the OLED technologies need to go more for the large-sized AMOLED TV marketplace.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.22 no.1
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• pp.11-32
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• 2009

Objective : This study was designed to investigate anti-cancer and whitening activities (LC). So it was investigated the effects of LC on proliferation rates of melanoma genetic profile by LC. Methods : The genetic profile for the effect of LC on human derived melanoma cell, SK-MEL-2, was measured using microarray technique, and the functional analysis on these genes were conducted. Total 441 genes were up-regulated and 830 genes down-regulated in cells treated with LC. Genes induced or suppressed by LC were all mainly concerned with basic signalling pathways, which are involved in cell growth, differentiation and migration. Especially, many genes, which are related in apoptosis and cell cycle arrest were up-regulated by treatment with LC, and genes related in cell cycle were down-regulated. Result : The network of total protein interactions were identified by using cytoscape program, and some key molecules, such as BCL2L1, SIN3A, SMAD2 and c-myc that can be used for elucidation of therapeutical mechanism of medicine in the future. Conclusion : These results suggest possibility of LC as addition drug and whitening cosmetics. In addition, it was also suggested that related mechanisms are involved in BCL2L1, SIN3A, SMAD2 and c-myc related signalling pathways.

• The Transactions of the Korean Institute of Power Electronics
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• v.10 no.2
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• pp.117-123
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• 2005

The cutoff frequency of a LC output filter for Dynamic Voltage Restorers (DVR) limits the control bandwidth of a DVR system while it attenuates the inverter switching ripples. For a selected cutoff frequency of a LC output filter, infinite number of L-C combinations is possible. Although different L-C combination has different filter characteristics, the filter design on L-C combination has been depended on field experiences without clear analysis. This paper proposes a design criterion and design examples for the L-C filter combination considering the control characteristics and the size of DVRs. An experimental DVR system based on the proposed LC output filter design methodology is built and tested.

• Journal of the Korea Organic Resources Recycling Association
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• v.26 no.3
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• pp.23-31
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• 2018

This study was carried out to investigate the effects of livestock manure compost and fish-meal liquid fertilizer on the growth of cucumber and the soil properties for the stable production of organic cucumber. Cucumber was transplanted in greenhouse on the $6^{th}$ of April in 2017, and this experiment contained five treatments: livestock manure compost 100% (LC 100%), livestock manure compost 50% + fish-meal liquid fertilizer 50% (LC50 + LF50), livestock manure compost 50% (LC50), chemical fertilizer (NPK), and no fertilizer (NF). As a result, it was shown that soil chemical properties of LC50 + LF50 plot is not different from that of LC100 plot except for the EC content, but soil chemical properties of LC50 + LF50 plot is statistically significantly different from that of NPK plot except for pH. As a result of evaluating the functional diversity of soil microbial communities using Biolog system, the substrate richness (S) and the diversity index (H) were the highest in LC50 + LF50 plot. As a result of comparing the cucumber growth and yield, it was found that there was no statistically significant difference between the plant height and the fresh weight of LC100, LC50 + LF50, and NPK plot, but the plant height and the fresh weight of LC100, LC50 + LF50, and NPK plot were different from that of LC50 and NF plot. The yield of cucumber was the highest in NPK plot r(7,397 kg/10a), but there was no statistically significant difference in the yield of cucumber between NPK plot and LC100, LC50 + LF50 plot. The above-described results suggested that the livestock manure compost and fish meal liquid fertilizer can be used for organic cucumber production under greenhouse condition.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.4 no.4
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• pp.298-304
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• 1999

Toxic effect of landfill leachate on the larvae and juvenile stage of the river puffer fish, Takifugu obscurus, were investigated in order to assess severity of environmental impact of leachate effluent on the general population of estuarine fishes. A short-term toxic experiment was designed to test both laboratory hatched larvae and juveniles (5, 10 and 15 mm in length) and in-situ juveniles (30 and 45 mm in length) using the leachate concentrations between 0 and 16%. Lethal concentrations of 50% mortality ($LC_{50}$) were observed using Spearman-karber Method. 24hr-$LC_{50}$ appeared at the leachate concentrations ranging from 3.03 to 8.57%, 48hr-$LC_{50}$ at 2.73 to 6.21 %, 72hr-$LC_{50}$o at 2.45 to 5.53%, and 96hr-$LC_{50}$ at 2.38 to 4.93%, respectively. Leachate concentrations between 0.69 and 1.51% induced 96hr-$LC_1$. Respiratory frequency was significantly affected even at low leachate concentrations between 0.5 and 1.0% (P < 0.05). These results suggest that the leachate effluents may cause a harmful impact on the physiology of river puffer fish, especially for younger cohorts.