• Applied Chemistry for Engineering
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• v.26 no.5
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• pp.621-623
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• 2015

This article describes a purification method yielding high purity of MFB produced from DMT production process. Aldehyde functional group of MFB included in side-products were converted to acetal compound via reacting with methanol and further separated. Hydrolysis process of the acetal product was continued under acidic condition and highly pure MFB were obtained with 90% yield. The structure of MFB was analyzed by $^1H$ NMR and $^{13}C$ NMR spectroscopy. Also, the purity of MFB was estimated to be over 99% by GC analysis.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 2000.04a
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• pp.193-198
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• 2000

PCBs를 분해하는 bphABC유전자를 plasmid vactor pMFB2에 유전자조작한 Pseudomonas putida AC30(pMFB2)를 PCBs에 오염된 연안해역의 해수와 저니로 만든 microcosm에 도입한 결과, 각각 도입 4일과 7일만에 사멸하였다. 그러나, 도입한 P. putida AC30(pMFB2)는 사멸하였지만, 연안해수와 저니 microcosm에서 plasmid pMFB2가 전이한 토착미생물이 검출되었다. 도입한 P. putida AC30(pMFB2)의 생잔실패의 원인을 분석한 결과 공경 0.2$\mu\textrm{m}$의 filter를 통과하는 물질과 생물이 가장 크게 영향을 미치는 것으로 나타났다. 유전자조작 P. putida AC30(pMFB2)의 도입과 bphABC유전자의 토착미생물로의 전이에 따른 토착미생물군집에 미치는 영향을 개체수 변동으로 조사한 결과, 토착미생물 군집에 미치는 영향은 보이지 않았다. P. putida AC30(pMFB2)의 도입에 의한 PCBs의 생분해성을 분석하였다. 그러나, 도입한 유전자조작 균주가 생잔에 실패함으로써 잔류하고 있는 PCBs의 농도변화는 보이지 않았다.

• Proceedings of the KIEE Conference
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• 2008.04a
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• pp.99-100
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• 2008

This paper proposes a Gaussian Mixture Model (GMM) - based speech emotion recognition methods using four feature parameters; 1) Fast Fourier Transform(FFT) spectral entropy, 2) delta FFT spectral entropy, 3) Mel-frequency Filter Bank (MFB) spectral entropy, and 4) delta MFB spectral entropy. In addition, we use four emotions in a speech database including anger, sadness, happiness, and neutrality. We perform speech emotion recognition experiments using each pre-defined emotion and gender. The experimental results show that the proposed emotion recognition using FFT spectral-based entropy and MFB spectral-based entropy performs better than existing emotion recognition based on GMM using energy, Zero Crossing Rate (ZCR), Linear Prediction Coefficient (LPC), and pitch parameters. In experimental Results, we attained a maximum recognition rate of 75.1% when we used MFB spectral entropy and delta MFB spectral entropy.

• Journal of the Institute of Convergence Signal Processing
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• v.9 no.2
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• pp.121-128
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• 2008

Accurate voice activity detection have a great impact on performance of speech applications including speech recognition, speech coding, and speech communication. In this paper, we propose methods for voice activity detection that can adapt to various car noise situations during driving. Existing voice activity detection used various method such as time energy, frequency energy, zero crossing rate, and spectral entropy that have a weak point of rapid. decline performance in noisy environments. In this paper, the approach is based on existing spectral entropy for VAD that we propose voice activity detection method using MFB(Met-frequency filter banks) spectral entropy, gradient FFT(Fast Fourier Transform) spectral entropy. and gradient MFB spectral entropy. FFT multiplied by Mel-scale is MFB and Mel-scale is non linear scale when human sound perception reflects characteristic of speech. Proposed MFB spectral entropy method clearly improve the ability to discriminate between speech and non-speech for various in noisy car environments that achieves 93.21% accuracy as a result of experiments. Compared to the spectral entropy method, the proposed voice activity detection gives an average improvement in the correct detection rate of more than 3.2%.

• Applied Microscopy
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• v.16 no.2
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• pp.49-60
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• 1986

Ultrastructures of the large and elongated cells (idioblasts) in the haustorium of a parasitic angiosperm, Cuscuta australis R. Brown growing on the host plant, Trifolium repens L. were investigated by the electron microscopy. The idioblasts were characterized by the presence of a large nucleus, small vacuoles, and dense cytoplasm including a number of various cell organelles such as ribosome, rough endoplasmic reticulum(r-ER), mitochondrion, dictyosome, proplastid, multilamellar structure(MLS), microfilament bundle(MFB), and cytosegresome. Therefore, it is suggested that the idioblasts are metabolical1y very active. Particularly, MLS, MFB, and cytosegresome observed in this study did not appear in the haustorial cells of the other parasitic angiosperms. MLS was transformed into vacuole and also incorporated with cell wall. MFB composed of microfilaments, about each 7.5 nm in diameter, was observed in nucleus and also cytoplasm. Some types of MFB were distinguished on the basis of arrangement of microfilaments. A part of cytoplasm sequestered by stacked cisternae of smooth ER(s-ER), cytosegresome, was altered into a vacuole which was formed by digestion of the sequestered cytoplasm and of cisternae of s-ER. Cell organelles such as MLS, MFB, and cytosegresome were discussed in relation to the metabolic control of the idioblasts.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.11C
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• pp.682-693
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• 2011

Energy spreading transform (EST) based modulation is an effective technique to combat frequency-selective fading in broadband wireless communication. It performs close to the inter-symbol interference (ISI)-free matched filter bound (MFB) only at the complexity of a linear detector. Originally, EST-based modulation has been proposed for QPSK. However, to fully utilize the capacity of multipath fading channels, higher-order modulations are also necessary. In this paper, we review the EST based modulation that has originally been proposed for QPSK and discuss its extension to 8 PSK and 16 QAM. The performance of the extended system is verified through simulation in Proakis B and 8-tap fading channel. The EST based modulation for 8 PSK shows the performance which is very close to MFB and the EST based modulation for 16 QAM shows the performance gap between its receiver and MFB.

• Applied Chemistry for Engineering
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• v.28 no.3
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• pp.294-298
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• 2017

Six new fluorescent whitening agent's candidates with 4,4'-di((E)-styryl)-1,1'-biphenyl skeleton which is the same as that of Uvitex FP family were synthesized using methyl 4-formylbenzoate (MFB) as a starting material. MFB has been disposed as a by-product of dimethyl terephthalate (DMT) production process. Six candidates were synthesized by the reaction of MFB, and its derivatives with tetraethyl biphenyl-4,4'-diylbis(methylene)diphosphonate (3) using Wittig-Horner reaction. A series of UV spectra were recorded and the results were used for estimating molar absorptivities of each candidates in order to find their potential application as fluorescent whitening agents. Considering the molar absorptivity (log ${\varepsilon}$ 3.95~2.60) for all candidates was lower than that of the commercial Uvitex FP 127 (log ${\varepsilon}$ 4.85), it was concluded that they are not suitable for fluorescent whitening agent applications.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.41 no.9
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• pp.597-603
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• 2017

In this study, experiments were conducted on the MFB(minimum film boiling) point of highly heated vertical metal rod quenched in aqueous surfactant solution at various temperature conditions. The aqueous Triton X-100 solution(100 wppm) and pure water were used as the liquid pool. Their temperatures ranged from $77^{\circ}C$ to $100^{\circ}C$. A stainless steel vertical rod of initial center temperature of $500^{\circ}C$ was used as a test specimen. In both liquid pools, as the liquid temperature decreased, the time to reach the MFB point decreased with a parallel increase in the temperature and heat flux of the MFB point. However, over the whole present temperature range, in the aqueous Triton X-100 solution, the time to reach the MFB point was longer, while the temperature and heat flux of the MFB point were reduced when compared with pure water. Based on the present experimental data, this study proposed the empirical correlations to predict the MFB temperature of a high temperature vertical metal rod in pure water and in aqueous Triton X-100 solution.

• Applied Chemistry for Engineering
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• v.27 no.2
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• pp.195-198
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• 2016

A total four-step synthetic process of high quality optical brightening agent 4,4'-bis(2-benzoxazolyl)stilbene (BBS) from methyl 4-formylbenzoate (MFB) was developed with 73% total yield. MFB is one of the main by-products in dimethyl terephthalate (DMT) production process. Our process involves the formation of 4,4'-stilbenedicarboxylate (2) obtained from the reaction of an aldehyde in MFB with ethyl 4-((diethoxyphosphoryl)methyl)benzoate (1) and the subsequent transformation to 4,4'-stilbenedicarbonyl chloride (3). In order to prepare benzoxazole ring in BBS, various solvents and catalysts were studied. The best solvent and catalyst were found to be 1,2,4-trichlorobenzene and boric acid, respectively suitable for mass production of BBS.

• Applied Chemistry for Engineering
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• v.27 no.5
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• pp.508-511
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• 2016

A facile synthesis of 4-(aminomethyl)cyclohexanecarboxylic acid (AMCA) from recyclable methyl 4-formylbenzoate (MFB) was described. In particular, we investigated the best process variables such as catalyst, hydrogen pressure, reaction temperature, and reaction time for AMCA conversion from AMBA through hydrogenation reaction. The best conditions were found to be as follows: the catalyst as [5% Pd/C, 5% Pt/C, 5% Rh/C (1 : 1 : 1)] which is a composite catalyst, the pressure as 30 bar, the reaction time as 8 hours and the reaction temperature at $130^{\circ}C$. Under the condition, a 90% yield (purity 99.9%) for the mass production of AMCA was achieved.