• Korean Journal of Environmental Agriculture
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• v.17 no.2
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• pp.160-163
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• 1998

In this study, the compostable household wastes from a house were composted in a home composter without adding any bulking agent and microorganisms. Every day wastes of 1kg were added to the composter during the experimental period. The following results were obtained : 1. Each component of the compostable household wastes generated every day showed very difference. 2. While composting proceeded at room temperature by suppling 1,1322 l air per hour, the composting material maintained the water content of 74.36 ${\sim}$ 85.14%, whereas while composting proceeded at $45^{\circ}C$ by suppling 427 l air per hour, the compost had optimal water content. The electric power of 132kwh a month was required by operating the composting unit at $45^{\circ}C$. 3. During 20 day, decomposition of 28% at room temperature and 44% at $45^{\circ}C$ were obtained respectively. 4. The accumulation of inorganic compound contents were not shown during the composting period, However, the content of salt and Cd was very high. Therefore, using the compost for agriculture has to be careful. 5. The biofilter removed the odorous substants efficiently at the room temperature due to increasing surface loading.

• Korean Journal of Food Science and Technology
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• v.47 no.4
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• pp.413-418
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• 2015

This study was conducted to analyze the functional component contents and antioxidant activities of Cedrela sinensis extracts hydrolyzed using four different enzymes. The yield of Viscozyme extract was the highest among the samples, and all enzymatic extracts, except for the commercial glucoamylase (AMG) extract, had significantly higher total polyphenol and flavonoids contents compared to the non-enzymatic extract (p<0.05). Viscozyme extract showed the highest 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity and $Fe^{2+}$ chelating ability among the samples. All enzymatic extracts showed high>90% 3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical scavenging activity, and there was no significant difference between the enzymatic and non-enzymatic extracts. The reducing power of the extracts using Shearzyme or Viscozyme was significantly higher than that of the other samples (p<0.05). Therefore, the results indicated that all enzymatic extracts (especially Viscozyme extract), except for the AMG extract, showed high antioxidant activity compared to the non-enzymatic extract. These result suggested that the enzymatic extracts of C. sinensis can be used in functional foods.

• Journal of Internet Computing and Services
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• v.19 no.3
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• pp.49-56
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• 2018

Euclidean distance (ED) between error distribution and Dirac delta function has been used as an efficient performance criterion in impulsive noise environmentsdue to the outlier-cutting effect of Gaussian kernel for error signal. The gradient of ED for its minimization has two components; $A_k$ for kernel function of error pairs and the other $B_k$ for kernel function of errors. In this paper, it is analyzed that the first component is to govern gathering close together error samples, and the other one $B_k$ is to conduct error-sample concentration on zero. Based upon this analysis, it is proposed to normalize $A_k$ and $B_k$ with power of inputs which are modified by kernelled error pairs or errors for the purpose of reinforcing their roles of narrowing error-gap and drawing error samples to zero. Through comparison of fluctuation of steady state MSE and value of minimum MSE in the results of simulation of multipath equalization under impulsive noise, their roles and efficiency of the proposed normalization method are verified.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.6
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• pp.810-814
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• 2008

This study was conducted to examine the effect of a gamma irradiation on the antioxidant activity of ethanol extract from cooking drips of Thunnus thynnus (ECT). The electron donating ability against 1,1-diphenyl- 2-picryl-hydrazyl (DPPH), authentic hydroxyl radical scavenging activity by Ultra Weak Luminescence Analyzer, oxidative protection factors by Racimat method, ferric reducing antioxidant power (FRAP), and ${\beta}$-carotene bleaching activity were measured as indices of antioxidant activity. All of the results shown that irradiation increased the antioxidant activity of ECT. These results suggested that ECT could be used as an antioxidative component in food and gamma irradiation could enhance these antioxidative properties.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.42 no.4
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• pp.819-830
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• 2017

An FM radio based PCL system is a passive radar technique for detecting the multiple moving targets from FM radio signals and tracking the trajectories of the targets by calculating the cross-correlation function of direct-path signal and target echo signals. However, the interference signals are received from a surveillance channel, which is designed to receive the target echo signals. Because of this problem, the target echo signals are masked by the strong interference signals and this makes it difficult to detect the true targets from the cross-correlation function. Adaptive filters are known as effective methods for suppressing the interference signals but there is a problem to present their accurate performances in the PCL system because many literatures used the cross-correlation function and the ratio of input and output power as a measure of the performance analysis. In this paper, a performance analysis method is proposed to evaluate the performance of interference cancellation algorithms. By using the property that each component of the filter weight vector is adjusted to suppress the specific interference signal, a performance measure of the interference signal suppression is defined by a function of adaptive filter weights. Based on the proposed method, we compare the performance of the adaptive filters used in the PCL system. Simulation results show that the proposed method can be very effective for evaluating the performance of interference cancellation algorithms.

• Food Science and Preservation
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• v.19 no.2
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• pp.263-270
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• 2012

The chemical components and anti-oxidant activities of black currant were investigated. The pH, soluble solid and total acidity values were 3.36, 15.11 $^{\circ}Brix$, and 1.65%, respectively. The Hunter L, a, and b values were 18.20, 5.13, and 1.08, respectively. The proximate compositions were as follows; moisture, 77.64%; nitrogen free extract, 17.41%; crude fiber, 3.08%; crude protein, 1.28%; crude ash, 0.31%; and crude lipid, 0.28%, respectively. The mineral elements were K (177.36 mg/100 g), P (54.74 mg/100 g), and Ca (26.45 mg/100 g). The free sugar components were glucose (7.71%) and fructose (5.88%). The amino acid contents of the black currant were very rich in glutamic acid (105.73 mg/100 g) and deficient in cystine (5.29 mg/100 g). The ascorbic acid and total phenolic contents were 112.19 mg/100 g and 34.48 mg GAE/g, respectively. The ABTS and DPPH radical scavenging activity levels were 99.48% and 89.03% at the 10 and 1.25 mg/mL concentrations. The reducing power and FRAP of the black currant were dose-dependent. Thus, black currant can be an effective source of functional food substances, i.e., natural anti-oxidants.

• Microbiology and Biotechnology Letters
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• v.38 no.4
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• pp.373-378
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• 2010

Studies on standardization and quality upgrade of nuruk which is a basic component in brewing are required to increase the quality level of Korean traditional rice wines and to develop the technology for practical use of it. It is important to isolate best strains, to improve the properties and effectively preserve them for brewing industry. In this study, 16 commercial nuruk samples were obtained from the commercial markets located in Chungcheong areas in Korea. 174 fungal strains were isolated from the samples on DG18 medium using a dilution plating method and then screened for enzyme activity and acid production. The active strains were identified based on the morphological characteristics and ITS sequence analysis. Out of 174 strains, 12 strains showed high amylase activity. Especially, Rhizopus sp. CN084, CN174, Aspergillus sp. CN161 and Mycocladus sp. CN042 showed high saccharogenic power and dextrinogenic enzyme activity on cooked wheat bran medium. On the other hand, Aspergillus sp. CN010, CN161, Rhizopus sp. CN105, CN168 and Rhizomucor sp. CN088 produced high acid production on the same medium. Our results showed that the active strains may be used as microbial sources for nuruk starter with good quality in brewing.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.1
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• pp.74-79
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• 2014

The purpose of this study was to determine the efficacy of Aster koraiensis Nakai as a natural health food source. To accomplish this, the general and antioxidative contents of A. koraiensis were measured. Total contents of carbohydrates, crude protein, crude lipid, and ash were 72.15%, 13.49%, 5.09%, and 9.27%, respectively. Caloric content of A. koraiensis was 349.70 kcal, while total dietary fiber was 49.79%. Total proteins consisted of 18 different kinds of amino acids. Contents of essential and non-essential amino acids were 4.6 and 5.5 g/100 g, respectively. Regarding mineral contents, P was the most abundant mineral, followed by K, Ca, and Na. Therefore, A. koraiensis is an alkali material. Total phenol contents of the hot water and 80% ethanolic extracts of A. koraiensis were $87.7{\pm}5.01$ and $112.4{\pm}3.41$ mg GAE/g, respectively. Total flavonoid contents of the hot water and 80% ethanolic extracts were $86.6{\pm}3.71$ and $95.1{\pm}8.00$ mg RE/g, respectively. The DPPH radical-scavenging activity and reducing power of the 80% ethanolic extract of A. koraiensis were higher than those of the water extract. Therefore, the general nutrients and antioxidant bioactive materials in A. koraiensis are potential materials for health foods.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.4
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• pp.450-455
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• 2012

In this study, the nutritional components and antioxidant activities of boysenberry were investigated. The values of pH, soluble solids, and total acidity were 3.62, $13.436^{\circ}Brix$, and 1.15%, respectively. Hunter L, a, and b values were 20.14, 13.19, and 3.20, respectively. Proximate compositions were as follows: moisture 79.52%, crude protein 1.08%, crude lipid 0.73%, crude fiber 2.51%, ash 0.62%, and nitrogen free extract 15.54%. Mineral contents of boysenberry were K 219.30, P 46.25, and Ca 39.60 mg/100 g. Regarding amino acid contents, boysenberry was very rich in alanine 75.22 mg/100 g and deficient in cystine 2.83 mg/100 g. Free sugar compositions were as follows: glucose (6.91%) and fructose (5.88%). Contents of ascorbic acid and total phenolics were 79.52 mg/100 g and 39.20 mg GAE/g, respectively. The DPPH radical scavenging activity and reducing power of boysenberry extract were 89.11% and 1.31 (absorbance) at a concentration of 1.25 mg/mL, respectively. Therefore, boysenberry can be utilized as an effective source of functional food substances such as natural antioxidants.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.43 no.4 s.310
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• pp.9-18
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• 2006

In the digital camera system, CMOS image sensor (CIS) is widely used because its size and weight become smaller and power consumption becomes lower. However, there are common problems that colors of the recorded image do not match those of the photographed object and that spectral sensitivity of the CIS used in different cameras varies largely in each case. Therefore, color correction is needed because the spectral sensitivity of the CIS in each color is neither the same color component for most standard colors nor the appropriate color representation for any output devices. In the conventional method, a color correction is empirically obtained by a large number of iterative experiments, but the result is not so satisfied. In this paper, a new method to obtain the efficient color correction matrix for digital camera using CIS is proposed. We obtain camera transfer matrix under the certain white-balance point, and color correction matrix that makes the transfer characteristic of digital camera close to the transfer characteristic of ideal camera is obtained. The experimental results show that the transfer characteristic of digital camera by the proposed method is close to that of the ideal camera. In addition, the image quality of pictures of digital camera using the proposed method is dramatically improved.