• Journal of the Korean Applied Science and Technology
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• v.22 no.2
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• pp.106-115
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• 2005

Bio-diesel as fatty acid methyl ester was derived from such oils as soybean, peanut and canola oil by lipase catalyzed continuous trans-esterification. So the activation of lipase(Novozym - 435) was kept to be up to 4:1, the limiting molar ratio of methanol to oil under one-step addition of methanol due to the miscibility of oil and methanol through the static mixer for 4hrs and the elimination of glycerol on the surface of lipase by 7wt% silica gel. Therefore the overall yield of fatty acid methyl ester from soybean oil appeared to be 98% at 50$^{\cdot}C$ of reaction temperature under two-steps addition of methanol with 2${\times}$2:1 of methanol to oil molar ratio at an interval of 5.5hrs, 7wt% of lipase, 24 number of mixer elements, 0.2ml/min of flow rate and 7wt% of silica gel.

• Proceedings of the KOSOMBE Conference
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• v.1997 no.05
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• pp.290-294
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• 1997

Chromosomes, as the genetic vehicles, provide the basic material for a large proportion of genetic investigations. The human chromosome analysis is widely used to diagnose genetic disease and various congenital anomalies. Many researches on automated chromosome karyotype analysis has been carried out, some of which produced commercial systems. However, there still remains much room for improving the accuracy of chromosome classification. In this paper, we propose an optimal pattern classifier by neural network to improve the accuracy of chromosome classification. The proposed pattern classifier was built up of two-step multi-layer neural network(TMANN). We are employed three morphological feature parameters ; centromeric index(C.I.), relative length ratio(R.L.), and relative area ratio(R.A.), as input in neural network by preprocessing twenty human chromosome images. The results of our experiments show that our TMANN classifier is much more useful in neural network learning and successful in chromosome classification than the other classification methods.

• Journal of the East Asian Society of Dietary Life
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• v.5 no.2
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• pp.27-38
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• 1995

This study was conducted to standardize ingredient ratio and preparation method of mafor traditional special kimchies in kyungsang province, korea. There were about 35 varieties of special kimchi in Kyungsang province. Six varieties of them such as burdock kimchi, wild leek kimchi, green thread onion kimchi, perilla leaf kimchi, Godulbaegi(Korean wild lettuce) kimchi, and red pepper leaf kimchi were selected, because they tasted good and the physiological functions of their main ingredients were excellent. The ingredient ratios of the selected special kimchi were standardized through surveying hereditary preparation of some families in kyungsang province and using the literatures including cooking books. The standardized ingredient ratio of the burdock kimchi was 15.1 pickled anchovy juice, 6.8 red pepper powder, 5.7 garlic, 2.2 ginger, 18.0 rice flour paste, 13.5 green thread onion, and 1.2 sesame seed in proportion to 100 of burdock. The standardized preparation step of the selected special kimchies was similar except some preprocessing methods of main ingredients. The diagonally cut-up burdock ws usually parboiled or soaked in salted water, then it was mixed with the other ingredients. Wild leek and green thread onion were usually pickled with salt or pickled anchovy juice. Sometimes the green thread onion pickled was dried in the sun. General preprocessing of perilla leaf, Korean wild lettuce, and red pepper leaf was soaking them in salted water for about 5-10 days. Sometimes red pepper leaf was heated with steam and dried in the sun, then it was mixed with the other ingredients.

• International Journal of Advanced Culture Technology
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• v.4 no.2
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• pp.47-56
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• 2016

In transformer cooling systems, oil temperature is controlled through the use of a blower and oil pump. For this paper, set-point algorithms, a reset algorithm and control algorithms of the cooling system were developed by neural networks and fuzzy logics. The oil inlet temperature was set by a $2{\times}2{\times}1$ neural network, and the oil temperature difference was set by a $2{\times}3{\times}1$ neural network. Inputs used for these neural networks were the transformer operating ratio and the air inlet temperature. The inlet set temperature was reset by a fuzzy logic based on the transformer operating ratio and the oil outlet temperature. A blower was used to control the inlet oil temperature while the oil pump was used to control the oil temperature difference by fuzzy logics. In order to analysis the performance of these algorithms, the initial start-up test and the step change test were performed by using the dynamic model of a transformer cooling system. Test results showed that algorithms developed for this study were effective in controlling the oil temperature of a transformer cooling system.

• Proceedings of the KOSOMBE Conference
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• v.1997 no.11
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• pp.133-136
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• 1997

The human chromosome analysis is widely used to diagnose genetic disease and various congenital anomalies. Many researches on automated chromosome karyotype analysis has been carried out, some of which produced commercial systems. However, there still remains much room or improving the accuracy of chromosome classification. In this paper, We propose an optimal pattern classifier by neural network to improve the accuracy of chromosome classification. The proposed pattern classifier was built up of multi-step multi-layer neural network(MMANN). We reconstructed chromosome image to improve the chromosome classification accuracy and extracted three morphological features parameters such as centromeric index(C.I.), relative length ratio(R.L.), and relative area ratio(R.A.). This Parameters employed as input in neural network by preprocessing twenty human chromosome images. The experiment results show that the chromosome classification error is reduced much more than that of the other classification methods.

• Proceedings of the KIEE Conference
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• 2000.07c
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• pp.1984-1986
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• 2000

In pulsed-power techniques. Marx generator is generally used for the high-power device. but this generator has insulation and spatial problems. So we will suggest a pulse transformer that has a small size to generate the high voltage pulse instead of Marx generator. In this paper, Pulse duration is 4 [${\mu}s$] and the ratio of input and output voltage is 40[kV]/200[kV](step-up ratio=5). The output voltage and the process of pulse compression for pulse circuit are simulated by EMTP (Electro-Magnetic Transient Program). The secondary voltage of pulse transformer is about 200[kV] and pulse width is 4[t/s]. When the secondary winding of the pulse transformer is saturated. the pulse width is 1.25[${\mu}s$]. We selected dummy load 50[$\Omega$] for impedance matching. The pulse voltage of dummy load is 100[kV] and pulse width is 500[ns].

• The Journal of Korean Physical Therapy
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• v.26 no.1
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• pp.1-8
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• 2014

Purpose: The aim of the present study was to understand the relationship between gait symmetry and functional balance, walking performance in stroke patients and to makes recommendation regarding the most suitable measure for standardization of expression of spatiotemporal gait symmetry. Methods: 45 subjects with stroke (31 men, 14 women, $57.3{\pm}10.3$ years old) participated in this study. Gait symmetry was calculated by equations of symmetry ratio (SR) and symmetry criterion (SC) for stance time, swing time, single leg support time (SLST), step length, and stride length. Spatiotemporal parameters were measured respectively by walkway system ($GAITRite^{TM}$ system). Limit of stability (LOS) by using forceplate (Balance Performance Monitor) during voluntary weight displacement and Berg Balance Scale (BBS) were measured as functional balance and Timed Up and Go test (TUG) and Functional Ambulation Category (FAC) were assessed as functional walking. Results: SR in stance time and swing time was correlation with BBS, TUG and FAC (p<0.05). SR in SLST only with BBS (p<0.01), SR in step length only with FAC (p<0.05). SC in stance time was correlation with BBS and TUG (p<0.05). SC in swing time and SLST with BBS, TUG and FAC (p<0.01), SC in step length with TUG and FAC (p<0.01), SC in stride length with BBS and FAC (p<0.01). Conclusion: Gait symmetry in spatiotemporal gait parameters provides meaningful information about functional balance and walking performance in stroke subjects. Our analysis may support the recommendations of the symmetry criterion as equation for standardization of gait symmetry.

• Proceedings of the KIPE Conference
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• 2011.07a
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• pp.25-26
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• 2011

In some cases of grid connected system using photovoltaic modules, high voltage step up ratio is required. In this paper, non-isolated 2-stage cascaded boost converter with coupled inductor is proposed. Due to reduce the input current ripple and size of the inductor by using coupled inductor method, this topology is suitable for MIC(Module Integrated Converter). The operational characteristic of the proposed topology is verified through the theorical analysis, simulation and experimental waveform.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1305_1306
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• 2009

Recently, piezoelectric transformer is applied to wide fields. Multi layer piezoelectric transformer has the advantage of high step up ratio, high electromechanical coupling coefficient(Kp) and high mechanical quality factor(Qm), however it shows the peeling-phenomenon of electrode, and high price due to high sintering temperature. Therefore this study focus on the method for fabrication of high power rosen type piezoelectric transformers.

• Journal of Electrical Engineering and Technology
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• v.10 no.4
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• pp.1578-1588
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• 2015

In this paper, an improved KY converter is presented, which is constructed mainly by one charge pump capacitor and one central-tapped coupling inductor. Besides, a passive clamping snubber is added to this converter to improve the efficiency above half load. As compared to the KY converter, the voltage conversion ratio of the proposed converter is upgraded significantly. In this paper, the basic operating principles and mathematical deductions of the proposed converter are described, along with some experimental results provided to demonstrate the feasibility and effectiveness of the proposed converter.