• KSBB Journal
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• v.15 no.4
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• pp.337-341
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• 2000

The decanter is very useful to harvest biomass from plant cell cultures in large-scale process. It is very important to obtain high yield and low moisture content in recovered biomass so as to minimize solvent usage in subsequent extraction steps. Effluent clarity was also affected by the differential speed although this affect was more dramatic at higher flow rates than at lower flow rates. Moisure content was largely unaffected by flow rate. A decrease in moisture content was evident as differential speed decreased.

• Journal of Biosystems Engineering
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• v.22 no.4
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• pp.433-438
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• 1997

The freshness of apple was evaluated by characterizing the surface texture of flesh cells. The freshness index which was related to the amount of wrinkles on the cell surface was defined to quantify the freshness. Four parameters relevant to the amount of the cell wrinkles were selected and measured using image analysis including wrinkle extraction procedure and Fast Fourier Transform of a wrinkle-extracted image. Out of 4 parameters, three parameters had highly significant correlations with the time elapsed after harvest. But it was concluded that two parameters out of such 3 parameters could be used for description of freshness index.

• Journal of Nutrition and Health
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• v.36 no.2
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• pp.133-146
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• 2003

This study was performed to investigate the in vitro and in vivo anticancer effects of persimmon leaf extracts on human gastric cancer cells. In vitro anticancer effects of persimmon leaf extracts (water extract at 8$0^{\circ}C$ for 3 hours, water extract at room temperature for 48 hours, 50% ethanol extract at 8$0^{\circ}C$ for 3 hours, 50% ethanol extract at room temperature for 48 hours, 75% ethanol extract at 8$0^{\circ}C$ for 3 hours and 75% ethanol extract at room temperature for 48 hours) on SNU16 (Korean gastric cancer cell) were investigated by MTT assay. Persimmon leaf extracts exhibited strong in vitro anticancer effects. We found that the higher the ethanol content of the solvent, the stronger the in vitro anticancer effects. Extraction yields, contents of flavonoids, vitamin A, vitamin C and vitamin E were measured. We found that the higher the ethanol content of the solvent, the higher the extraction yields and the contents of flavonoids, vitamin A and vitamin E. Among persimmon leaf extracts, 75% ethanol 8$0^{\circ}C$ extract showed the highest extraction yield, the highest contents of flavonoids, vitamin A and vitamin E and exhibitied the strongest in vitro anticancer effect on SNU16. Therefore, 75% ethanol 8$0^{\circ}C$ extract was chosen as the material to investigate in vivo anticancer effects. In vivo anticancer effect of persimmon leaf 75% ethanol 8$0^{\circ}C$ extract was investigated in SNU16 transplanted nude mice. Twenty five female nude mice (BALB/c) were blocked into five groups according to body weight and raised for 4 weeks with diets containing 4% (w/w), 8% (w/w) persimmon leaf 75% ethanol 8$0^{\circ}C$ extract, with IT (intratumoral) injection treatment with 1.65 mg/100 $\mu$1, 3.3 mg/100 $\mu$1 concentration every other day 3 weeks after SNU16 was transplanted. Persimmon 75% ethanol 8$0^{\circ}C$ extract significantly lowered tumor weight and tumor volume in SNU16 transplanted nude mice. Tumor weight and tumor volume in all experimental groups were significantly lower than those in the control group. Helper T cell (CD4) levels of mice injected with 3.3 mg/100 $\mu$1 extract significantly increased. Cytotoxic T cell (CD8) levels in all experimental groups significantly increased and helper/cytotoxic T cell ratios in all experimental groups significantly decreased. Natural killer cell and MHC class II molecule in all experimental groups significantly increased. In conclusion, persimmon leaf 75% ethanol 8$0^{\circ}C$ extract exhibited strong in vitro and in vivo anticancer effects against SNU16 cells and it increased cytotoxic T cell, natural killer cell and MHC classII molecule in experimental groups in SNU16 transplanted nude mice.

• The Transactions of the Korean Institute of Power Electronics
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• v.14 no.5
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• pp.372-378
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• 2009

With the increase in capacity of photovoltaic generation systems, studies are being actively conducted to improve system efficiency. In order to develop the high performance photovoltaic power system it is required to understand the physical characteristics of the solar cell. However, solar cell models have a non-linear form with many parameters entangled and conventional methods suggested to extract the parameters of the solar cell model require some kind of assumptions, which accompanies the calculation errors, thereby lowering the accuracy of the model. Therefore, in this paper a novel method is proposed to calculate the ideality factor and reverse saturation current of the solar cell from the I-V curve measured and announced by solar cell manufacturers, derive the ideal I-V curve, and then extract the series and shunt resistances value from the difference between the ideal and measured I-V curve. Also, validity of the proposed method is demonstrated by calculating the correlation between I-V curve based on modeling parameters and I-V curve actually measured through least squares method.

• Proceedings of the IEEK Conference
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• 1998.06a
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• pp.82-85
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• 1998

Because ATM was originally designed for the optical fiber environment with bit error rate(BER) of 10-11, it is difficult to maintain ATM cell extraction capability in wireless environment where BER ranges from 10-6 to 10-3. Therefore, it must be proposed the algorithm of ATM cell extraction in wereless environment. In this paper, the frame structure and synchronization algorithm satisfyling the above condition are explained, and the new ASIC implementation method of this algorithm is proposed. The known method using shift register needs so many gates that it is not suitable for ASIC implementation. But in the proposed method, a considerable reduction in gate count can be achieved by using random access memory.

• The KSFM Journal of Fluid Machinery
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• v.15 no.5
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• pp.20-26
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• 2012

An APU(Auxiliary Power Unit) for helicopters has been developed in Korea and tested at the AETF(altitude engine test facility) in KARI(Korea Aerospace Research Institute) for the purpose of the military qualification. A cell correlation test was performed before the official test, and the results are within the tolerance. The APU has the capability of supplying electric power as well as compressed air to the helicopters. It was tested at bleed extraction conditions, electric power extraction conditions, and maximum continuous concurrent power conditions within the entire helicopter flight envelop. Some special test equipments were implemented for the measurement of air flowrate, electric power and so on. The tests were successfully performed and their results satisfy the requirements of the helicopters.

• Proceedings of the IEEK Conference
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• 2001.06b
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• pp.113-116
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• 2001

In this paper we present a new hierarchical layout object extraction algorithm, which is based on rectangles rather than edges. The original layout data is modeled as instances connected by wires. Each polygon shape is divided into a set of rectangles and the instances and wires are extracted and recognized from those rectangles together with their connection and size information. We have applied the algorithm to actual layouts. Experiments on several standard cell library demonstrate the effectiveness of the algorithm.

• Korean Chemical Engineering Research
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• v.50 no.3
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• pp.545-550
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• 2012

A 17-run Box-Behnken design (BBD) was used to optimize the extraction conditions of astaxanthin from shrimp waste. Three factors such as ratio of ethanol to raw material, extraction temperature ($^{\circ}C$) and extraction time (min) were investigated. The adjusted coefficient of determination ($R^2{_{adj}}$) for the model was 0.9218, and the probability value (p=0.0003) demonstrated a high significance for the regression model. The optimum extraction conditions were found to be: optimized ratio of ethanol to raw material 29.7, extraction temperature $49.5^{\circ}C$ and extraction time 59.9 min. Under these conditions, the mean extraction yield of astaxanthin was $17.80{\mu}g/g$, which was in good agreement with the predicted model value. Under these conditions, validation experiments were done and the mean extraction yield of astaxanthin was $17.77{\mu}g/g$, which is in good agreement with the predicted model value.

• Journal of Physiology & Pathology in Korean Medicine
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• v.26 no.6
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• pp.908-914
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• 2012

To investigate the difference and change of ingredient and efficacy of Galgeun-tang (GGT) according to extraction solvent, water and 70% EtOH, the quantities of index components and the several in vitro activities of two kinds of GGT extract were compared. The contents of extracts were analyzed with HPLC. The biological activities such as anti-inflammatory and anti-obesity effects were measured through cell line-based in vitro assay. The cytotoxicity was measured by CCK-8 assay in RAW 264.7 cell, BEAS-2B cell, HaCaT cell and 3T3-L1 cell. We compared effects of two kinds of extract by measuring NO, PGE2, IL-6 and TNF-${\alpha}$ in RAW264.7 cell, RANTES in BEAS-2B cell, MDC and RANTES in HaCaT cell and GPDH activity and leptin level in differentiated 3T3-L1. 70% EtOH extract of GGT contained more compositions than water extract. The inhibitory effect of water extract of GGT on NO in RAW 264.7 cell and GPDH activity in 3T3-L1 was stronger than that of 70% EtOH. 70% EtOH has a stronger inhibitory effect on PGE2 in RAW264.7 cell, RANTES in BEAS-2B cell, MDC, RANTES in HaCaT cell, leptin in 3T3-L1 cell than water extraction. These results suggest that the ingredient and efficacy from 70% EtOH extract of GGT are more effective than water extract.

• Journal of Korean Society on Water Environment
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• v.24 no.4
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• pp.488-498
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• 2008

Soil and Water Assessment Tool (SWAT) model have been widely used in simulating hydrology and water quality analysis at watershed scale. The SWAT model extracts topographic feature using the Digital Elevation Model (DEM) for hydrology and pollutant generation and transportation within watershed. Use of various DEM cell size in the SWAT leads to different results in extracting topographic feature for each subwatershed. So, it is recommended that model users use very detailed spatial resolution DEM for accurate hydrology analysis and water quality simulation. However, use of high resolution DEM is sometimes difficult to obtain and not efficient because of computer processing capacity and model execution time. Thus, the SWAT Topographic Feature Extraction Error (STOPFEE) Fix module, which can extract topographic feature of high resolution DEM from low resolution and updates SWAT topographic feature automatically, was developed and evaluated in this study. The analysis of average slope vs. DEM cell size revealed that average slope of watershed increases with decrease in DEM cell size, finer resolution of DEM. This falsification of topographic feature with low resolution DEM affects soil erosion and sediment behaviors in the watershed. The annual average sediment for Soyanggang-dam watershed with DEM cell size of 20 m was compared with DEM cell size of 100 m. There was 83.8% difference in simulated sediment without STOPFEE module and 4.4% difference with STOPFEE module applied although the same model input data were used in SWAT run. For Imha-dam watershed, there was 43.4% differences without STOPFEE module and 0.3% difference with STOPFEE module. Thus, the STOPFEE topographic database for Soyanggang-dam watershed was applied for Chungju-dam watershed because its topographic features are similar to Soyanggang-dam watershed. Without the STOPFEE module, there was 98.7% difference in simulated sediment for Chungju-dam watershed for DEM cell size of both 20 m and 100 m. However there was 20.7% difference in simulated sediment with STOPFEE topographic database for Soyanggang-dam watershed. The application results of STOPFEE for three watersheds showed that the STOPFEE module developed in this study is an effective tool to extract topographic feature of high resolution DEM from low resolution DEM. With the STOPFEE module, low-capacity computer can be also used for accurate hydrology and sediment modeling for bigger size watershed with the SWAT. It is deemed that the STOPFEE module database needs to be extended for various watersheds in Korea for wide application and accurate SWAT runs with lower resolution DEM.