• Journal of the Korean Society of Tobacco Science
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• v.31 no.1
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• pp.45-50
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• 2009

In this study, a simple gradient RRLC method for rapid determination of carbonyl compounds of cigarette smoke was developed. Within 10 min, 8 carbonyl compounds have been separated and identified on ZORBAX Eclipse XDB-C18 column ($4.6{\times}50\;mm$, $1.8\;{\mu}m$) with gradient elution using water and acetonitrile as a mobile phase. RRLC was used for the quantification of carbonyl compounds in mainstream smoke of 3R4F reference cigarette, and evaluated those efficiencies in the recovery, repeatability and reproducibility. The correlation coefficients ($r^2$) for calibration curves of carbonyl compounds were over 0.9998. The developed RRLC method was successfully applied to the analysis of smoke samples and the recoveries of carbonyl compounds were in the range of 97.5~102.1% with RSD<3.1%.

• Journal of the Korean Society for Precision Engineering
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• v.18 no.10
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• pp.184-193
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• 2001

In vector control technique, stator currents of an induction motor are transformed to equivalent d-q currents in a reference frame consist of d and q axis, each of which is coincide with flux and torque direction respectively. Since the current in q-axis is related to the torque in a synchronously rotating frame, torque is estimated as a function of q-axis current and flux. In this paper, a method to estimate torque of an induction motor based on the measurement of 3-phase currents and rotating velocity of a rotor is presented. Graphic-programming is used to measure signals, to estimate the torque and to show the result in the form of user friendly graph in window environment. To stabilize the fluctuation of estimated torque caused from the small measurement error of the rotor velocity, the stator current is reconstructed in a program based on measured signals. The experimental results executed under the velocity of 500 rpm, 1500 rpm without load and 1500 rpm with load show that the proposed method estimates the torque very well.

• Korean Journal of Pharmacognosy
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• v.31 no.3
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• pp.340-344
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• 2000

Lonicerae Flos, the flower of Lonicera japonica Thunb., has been used as a diuretic, stomachic, antipyretic, analgesic and anti-inflammatory agent in Korea. In order to evaluate the quality of Lonicerae Flos, the method of isolation and quantitative determination of luteolin $7-O-{\beta}-D-glucoside$ as a reference standard compound has been developed. Different specimens of Lonicerae Flos were collected from twenty Korean markets and were analyzed with HPLC using the mobile phase of MeOH-4.5% acetic acid solution (16.5:83.5). The average content of luteolin $7-O-{\beta}-D-glucoside$ from Lonicerae Flos in Korean markets was $0.43{\pm}0.34%$.

• Korean Journal of Pharmacognosy
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• v.31 no.3
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• pp.335-339
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• 2000

Polygoni Multiflori Radix, the root of Polygonum multiflorum Thunb., has been used as a tonic, and in the inflammation and constipation in Korea. In order to evaluate the quality of Polygoni Multiflori Radix, the method of isolation and quantitative determination of emodin as a reference standard compound has been developed. Different specimens of Polygoni Multiflori Radix were collected from twenty Korean markets and were analyzed with HPLC using the mobile phase of MeOH-water (64:36). The average content of emodin from Polygoni Multiflori Radix in Korean markets was 0.021%.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.19 no.8
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• pp.1433-1445
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• 1994

In this paper, an coherent optical correlator system based on the off-axis projection synthetic discriminant funtion (OA-pSDF) was analyzed and implemented optically. The filter was synthesized by combining conventional pSDF with single reference plane wave multiplexing. Synthesized pSDF were transformed to binary phase only filters (BPOFs) and fabricated as computer generated holograms(CGHs), which was used in the real time optical correlator system instead of using expensive spatial light modulators(SLMs). From the characteristic test, it was found that OA-pSDF showed distortion invariance and good performances in discrminating subset images. The proposed OA-pSDF BPOF could overcome the limitations of conventional BPOFs : that is distortion variance such as acale and rotation, especially out of plane variance.

• Korean journal of food and cookery science
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• v.30 no.5
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• pp.573-578
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• 2014

The objective of this study was to investigate the antioxidant activities and anthocyanin profiles in the anthocyanin rich fraction (ARFAM) of Aronia melanocarpa, which are considered functional substances and are available as food coloring agents in Korea. Anthocyanins were identified by reversed-phase C18 column chromatography and HPLC-DAD-ESI/MS analysis. The antioxidative activity of the acidic ethanol extract (AME) and the anthocyanin-rich fraction (ARFAM) was determined by scavenging of the diphenylpicrylhydrazyl (DPPH) radical, the hydroxy radical, and the superoxide anion in addition to reducing power using a commercial antioxidant as a reference.

• Food Quality and Culture
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• v.2 no.1
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• pp.27-31
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• 2008

The objective of this study was to develop sensory lexicons that can be utilized for various types of tofu such as pressed, unpressed, and tofu made from germinated soybeans, using generic descriptive analysis. In the first phase of the experiment, trained descriptive panelists developed and defined the appearance, aroma, flavor, and texture attributes that are commonly present in tofu. Then, the sensory characteristics of seven types of tofu were analyzed using the sensory lexicons established in the initial stage of the experiment. Four appearance, 6 odor/aroma, 6 flavor/taste, 7 texture, and 4 aftertaste attributes were identified, and reference standards were established for most of the terms in order to facilitate the understanding of the attribute definitions. The intensities of the sensory attributes were measured on a 15-point scale. Statistical analyses, including analysis of variance and principal component analysis, were used for the data. The seven tofu samples showed significant differences in the intensities of 22 attributes. The unpressed tofu samples were generally rated as being high in moistness, easy to cut, silky, and easy to swallow. The pressed tofu, on the other hand, was salty, astringent, beany, hard, and rough in texture. The tofu made with germinated soybeans was characterized as having a strong cooked bean flavor, salty and astringent aftertaste, and hard texture. Overall, the attributes of moistness, easy to swallow, and silkiness showed strong positive correlations; hardness and sticks to teeth were also positively correlated to each other.

• Journal of Microbiology and Biotechnology
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• v.15 no.3
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• pp.472-476
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• 2005

The present study was untaken to assess the capacity of Bacillus pumilis KHS-1 to grow on chicken flour and to prepare feather digest as fertilizer. To increase keratinolytic activity, the addition of cysteine (5.0 mM) showed the highest keratinolytic activity (245 unit) among the reducing agents tested. The production of soluble protein (feather digests) paralleled the tendency to the production of keratinolytic protease. In the growth curve of B. pumilis KHS-1 at $30^{\circ}C$ in the feather medium with 5 mM cysteine, the maximum keratinolytic activity of B. pumilis was about 161 units/ml after 84 h of incubation. The maximum enzyme activities were observed at the late logarithmic growth phase, and remained thereafter with little changes. Using 27-day plant growth assays on carrot and Chinese cabbage, feather digests and reference fertilizer were compared. In terms of the length and the weight of the above-ground vegetations, feather digests showed the same effect as that of the fertilizer. Therefore, our investigation shows that the feather digests can be used in agriculture.

• Transactions of the Korean hydrogen and new energy society
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• v.18 no.2
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• pp.132-139
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• 2007

Popular techniques for producing synthesis gas by converting methane include steam reforming and catalyst reforming. However, these are high temperature and high pressure processes limited by equipment, cost and difficulty of operation. Low temperature plasma is projected to be a technique that can be used to produce high concentration hydrogen from methane. It is suitable for miniaturization and for application in other technologies. In this research, the effect of changing each of the following variables was studied using an AC Glidarc system that was conceived by the research team: the gas components ratio, the gas flow rate, the catalyst reactor temperature and voltage. Glidarc plasma reformer was consisted of 3 electrodes and an AC power source. And air was added for the partial oxidation reaction of methane. The result showed that as the gas flow rate, the catalyst reactor temperature and the electric power increased, the methane conversion rate and the hydrogen concentration also increased. With $O_2/C$ ratio of 0.45, input flow rate of 4.9 l/min and power supply of 1 kW as the reference condition, the methane conversion rate, the high hydrogen selectivity and the reformer energy density were 69.2%, 36.2% and 35.2% respectively.

• Korean Journal of Construction Engineering and Management
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• v.16 no.2
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• pp.77-85
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• 2015

The data are often missed and many errors of the data are generated in the input process for the post evaluation system on the construction projects, and the reliability of the data falls down much. Accordingly, the detailed analysis about missing and error of data was conducted to ensure reliability of the analysis results about post evaluation on the construction projects. As results in this study, a lot of input data were missed at the initial construction phase, and the data errors were found in the inaccuracy of reference reports, the lack of understanding about input data, and the failure of KRW unit.