• 대한음성학회지:말소리
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• 제52호
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• pp.133-144
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• 2004

The quality of narrowband speech can be enhanced by the bandwidth extension technology. This paper proposes a mixed excitation and an energy compensation method based on Gaussian Mixture Model (GMM). First, we employ the mixed excitation model having both periodic and aperiodic characteristics in frequency domain. We use a filter bank to extract the periodicity features from the filtered signals and model them based on GMM to estimate the mixed excitation. Second, we separate the acoustic space into the voiced and unvoiced parts of speech to compensate for the energy difference between narrowband speech and reconstructed highband, or lowband speech, more accurately. Objective and subjective evaluations show that the quality of wideband speech reconstructed by the proposed method is superior to that by the conventional bandwidth extension method.

• 한국식품과학회지
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• 제53권2호
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• pp.126-132
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• 2021

Cheonggukjang (CGJ) is a famous traditional Korean food that is typically produced by fermenting steamed soybean seeds and has a unique flavor and taste. The objective of this study was to evaluate the effect of addition of lotus seeds on the quality and antioxidant activities of CGJ. Color value, 1,1-diphenly-2-picrylhydrazyl radical scavenging potential, and the amounts of total polyphenol, total flavonoid, mineral, and free amino acid were evaluated. The CGJ sample produced with lotus alone or a mixture of soybean and lotus produced in Korea showed relatively high antioxidant potential. The amount of essential and total free amino acids was also high in the sample prepared with lotus seeds grown in Korea. On the other hand, the total mineral content was low in the lotus-based samples. The results indicated that a mixture of an equal proportion of soybean and lotus seeds could be a good option to prepare nutritious CGJ.

• 한국물환경학회지
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• 제30권3호
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• pp.329-339
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• 2014

This study aims to estimate chlorophyll-a concentration in rivers using multi-spectral RapidEye imagery and Spectral Mixture Analysis (SMA) and assess the applicability of SMA for multi-temporal imagery analysis. Comparison between images (acquired on Oct. and Nov., 2013) predicted and ground reference chlorophyll-a concentration showed significant performance statistically with determination coefficients of 0.49 and 0.51, respectively. Two band (Red-RE) model for the October and November 2013 RapidEye images showed low performance with coefficient of determinations ($R^2$) of 0.26 and 0.16, respectively. Also Three band (Red-RE-NIR) model showed different performance with $R^2$ of 0.016 and 0.304, respectively. SMA derived Chlorophyll-a concentrations showed relatively higher accuracy than band ratio models based values. SMA was the most appropriate method to calculate Chlorophyll-a concentration using images which were acquired on period of low Chlorophyll-a concentrations. The results of SMA for multi-temporal imagery showed low performance because of the spatio-temporal variation of each end members. This approach provides the potential of providing a cost effective method of monitoring river water quality and management using multi-spectral imagery. In addition, the calculated Chlorophyll-a concentrations using multi-spectral RapidEye imagery can be applied to water quality modeling, enhancing the predicting accuracy.

• 마케팅과학연구
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• 제16권2호
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• pp.77-94
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• 2006

이 연구는 가격을 품질의 지표로 사용하는 상황의 가격반응함수를 도출하여 다음과 같은 연구를 수행하였다. 첫째, 다속성 선택기준의 조합을 이용하여 세분시장별로 가격을 품질의 지표로 사용하는 하위집단과 그렇지 않은 하위집단을 추출하였고, 둘째, 기존연구에서 사용된 분석단위인 제품이나 상표에서 벗어나 세분시장을 분석단위로 하여 가격이 품질의 지표로 사용되는 세분시장을 확인하였다. 이를 위해 첫째, 중국의 홈씨어터 시장을 대상으로 CBC(choice-based conjoint analysis)를 통해 얻어진 자료를 혼합회귀분석(mixture regression model)에 의해 시장 세분화하였고, 그 결과 표본전체시장 및 세개의 세분시장에서 가격을 품질의 지표로 사용하는 독특한 가격반응함수를 가진 세분시장을 확인하였다. 이를 통해 학술적으로는 가격-품질 평가집단 연구의 범위를 세분시장별로 확대하고, 실무적으로는 실무종사자는 가격-품질 평가가 이루어지는 가격대보다 높은 가격을 시장에 제시함으로써 이익을 더 많이 취할 수 있게 되는 장점을 기대하였다.

• 한국토양비료학회지
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• 제47권6호
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• pp.480-485
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• 2014

In satsuma mandarin (C. unshiu Marc. cv. Miyagawa), alternate bearing is frequently occurred. It is very difficult to control and maintain the optimum production because satsuma mandarin is a very sensitive citrus cultivar. We carried out the experiment to find out the effects of foliar application of gibberellic acid ($GA_3$) and machine oil emulsion mixture on flowering and fruit quality of satsuma mandarin grown on open field. The treatments were composed of control (no application), $GA_3$ (25, 50 and $100mg{\cdot}L^{-1}$), machine oil emulsion 100 times and mixture of $GA_3$ (25 and $50mg{\cdot}L^{-1}$) with machine oil emulsion 100 times on 16 year-old 'Miyagawa' satsuma mandarin on December 30, 2012. Foliar application of $GA_3$ during winter season led to a reduction of the flowering in the following year. $GA_3$ decreased flowering in dose dependant manner. However, application of $GA_3$ and machine oil emulsion (100 times-diluted mixture) inhibited effectively the flowering compared to $GA_3$ only. Also, flower-leaf ratio was significantly decreased by the application of $GA_3$ 25 (0.54) and $50(0.41)mg{\cdot}L^{-1}$ with machine oil emulsion mixture in comparison to $GA_3$ 25 (0.86) and $50(0.60)mg{\cdot}L^{-1}$ only. The number of leaves per fruit increased in application of $GA_3$ and machine oil emulsion mixture as concentration of $GA_3$ increased. Fruit weight and sugar-acid ratio also increased in comparison to the control whereas fruit size, soluble solid content and acidity remained unchanged. From the results, it was suggested that $GA_3$ application can reduce the number of flowers on the alternate bearing of satsuma mandarin. Moreover, application of $GA_3$ (25 and $50mg{\cdot}L^{-1}$) with machine oil emulsion 100 times mixture can reduce the flowering effectively without altering fruit maturity and soluble solid contents. Therefore, it can be concluded that the application of $GA_3$ 25 and $50mg{\cdot}L^{-1}$ with machine oil emulsion 100 times might be useful in controlling alternate bearing in satsuma mandarin.

• 한국유기농업학회지
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• 제12권2호
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• pp.231-241
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• 2004

In recent years, many researches are actively undertaken for environmental-friendly animal production according to the increased understanding about food safety because of the outbreak of various diseases such as mad cow disease, Foot and mouth disease and Poultry Influenza virus. However, high quality(higher safety)- animal production may not be successful without increasing of disease resistance of animal and the improvement of feeding environment. To increase the disease resistance is able to be accomplished by stimulating the immune function. The present study was undertaken to investigate the effects of enzyme mixture reinforced with ${\beta}$-glucanase activity which degrade polysaccharide to release ${\beta}$-glucan known as stimulator of immune function on the change of milk production and somatic cell count. After 12weeks of experimental feeding, milk production tended to be increased and somatic cell count was decreased from average $227{\times}10^4$ to $37.1{\times}10^4$. Milk protein and solid-fat content were tended to increase but milk fat showed decreasing tendency by the feeding of enzyme mixture. All together, it has been suggest6d that the improvement of high quality milk production may be possible through the dietary addition of immune modulating enzyme mixture in lactating dairy cows.

• 한국식생활문화학회지
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• 제21권6호
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• pp.685-694
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• 2006

The quality characteristics of cookies containing brown rice flour, which has a greater variety of functional components than wheat flour, were studied. The results of the pasting properties shows that the inclusion of brown rice flour to the wheat flour-mixture did not affect the pasting temperature for up to 30% inclusion. The total dietary fiber and total polyphenol content increased and color of the cookies became darker with increasing brown rice flour content. According to the results from TA on texture, the hardness decreased and the crispness increased significantly(p<0.001, p<0.05, respectively) with increasing brown rice flour content. From the acceptance test, the aroma and texture of the cookies with added brown rice flour were significantly(p<0.001) lower than those of the wheat flour cookies. However, the appearance, taste, and overall acceptance of the cookies with added brown rice flour did not differ significantly from those of the wheat flour cookies. According to the results from the sensory evaluation, the savory aroma of the cookie with 30% brown rice flour was significantly strong(p<0.001). The brown rice flavor of the cookies with brown rice flour was significantly stronger(p<0.001) than that of the wheat flour cookie, but there were no significant differences among the cookies with brown rice flour in it. The crispness of the cookies increased significantly(p<0.001) with the inclusion of brown rice flour in the mixture, especially for the mixture with 30% brown rice flour which had the highest value of crispness among the cookies. The graininess and brown color of the cookies increased significantly(p<0.001) with increasing brown rice flour content, especially for the mixture with 30% brown rice flour which had the highest values among the cookies.

• 한국식품조리과학회지
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• 제12권1호
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• pp.92-98
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• 1996

쌀가루(200 mesh)로 만든 슈의 품질을 향상시키기 위하여 가장 효과적인 첨가물의 종류와 첨가비율을 구명하고져 본 실험을 수행하였다. 첨가물로는 lecithin, span 20, span 40, span 80 등의 유화제와, gelatin, arabic pm, methylcellulose, CMC 등의 점증제를 사용하였다. 1. 쌀가루만으로도 슈형성은 가능하였다. 2. 그러나, 유화제를 첨가하면 쌀가루만의 무첨가구 보다 관능평가에서는 유의차가 없었지만 팽화력이 우수하였다. 3. 점증제로는 큰 효과가 없었으며, 오히려 다량첨가시에는 반죽의 경도가 커져서 슈내부에 공동이 형성되지 않았다. 4. 두가지의 유화제나 점증제와의 복합사용은 유화제 단독 사용시보다 효과가 없었다. 5. Lecithin을 0.6%로 첨가할 경우, 슈의 품질이 가장 우수하였다.

• International Journal of Automotive Technology
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• 제7권3호
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• pp.237-244
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• 2006

Limited and nonlimited emissions of scooters were analysed during several annual research programs of the Swiss Agency of Environment Forests and Landscape(SAEFL, BUWAL). Small scooters, which are very much used in the congested centers of several cities are a remarkable source of air pollution. Therefore every effort to reduce the emissions is an important contribution to improve the air quality in urban centers. In the present work detailed investigations of particle emissions of different 2-stroke scooters with direct injection and with carburetor were performed. The nanoparticulate emissions with different lube oils and fuels were measured by means of SMPS, (CPC) and NanoMet. Also the particle mass emission(PM) was measured with the same method as for Diesel engines. It can be stated, that the oil and fuel quality have a considerable influence on the particle emissions, which are mainly oil condensates. The engine technology influences the (nano)particle emissions by: mixture preparation, mixture tuning, oil consumption, postoxidation, quality, condition and temperature of the catalyst. Since the particulate emission of the 2-S consists mainly of lube oil condensates the minimization of oil consumption stays always an important goal.

• 설비공학논문집
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• 제5권3호
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• pp.217-225
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• 1993

Nonflammable mixtures of flammable and nonflammable refrigerants are possible as substitute refrigerants for use in domestic heat pumps and refrigerators. Refrigerant leakage from such a system is of paramount concern since it is possible that the resulting mixture composition remaining in system will reside in the flammable range. This paper presents a simulation of a leakage process of refrigerant mixtures. Idealized cases of isothermal leakage process are considered in this study representing a slow leak. Simulation is performed for selected composition of binary and ternary refrigerant mixture; R-32/134a and R-32/125/134a. Mixture compositions with respect to percentage leak of original charge are presented. In isothermal leakage process, both vapor and liquid compositions of more volatile refrigerant decrease during vapor and liquid leak, but the total composition of this component decreases during vapor leak and increases during liquid leak. Vapor and liquid compositions are determined depending on the vapor-liquid equilibrium relation of the refrigerant mixture. The refrigerant mixture left in the system can go to a nonflammable direction relying on which component in the mixture is flammable.