• The Journal of the Acoustical Society of Korea
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• v.39 no.2
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• pp.120-130
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• 2020

This paper solves the problem in underdetermined convolutive mixture by improving the disadvantages of the multichannel nonnegative matrix factorization technique widely used in blind source separation. In conventional researches based on Spatial Covariance Matrix (SCM), each element composed of values such as power gain of single channel and correlation tends to degrade the quality of the separated sources due to high variance. In this paper, level and frequency normalization is performed to effectively cluster the estimated sources. Therefore, we propose a novel SCM and an effective distance function for cluster pairs. In this paper, the proposed SCM is used for the initialization of the spatial model and used for hierarchical agglomerative clustering in the bottom-up approach. The proposed algorithm was experimented using the 'Signal Separation Evaluation Campaign 2008 development dataset'. As a result, the improvement in most of the performance indicators was confirmed by utilizing the 'Blind Source Separation Eval toolbox', an objective source separation quality verification tool, and especially the performance superiority of the typical SDR of 1 dB to 3.5 dB was verified.

• Journal of Life Science
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• v.27 no.6
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• pp.702-707
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• 2017

Insects and their extract have been traditionally used as medicinal resources in Asia. Recently, Gryllus bimaculatus and the larva of Tenebrio molitor, Protaetia brevitarsis, and Allomyrina dichotoma were enlisted as general food ingredients by Korean Ministry of Food and Drug Safety. As the interest in these insects is growing, the detailed investigation is needed for the standardization of suitable and safe rearing techniques. This survey was conducted via personal interviews about edible insect rearing farms in Korea. The basic feed is fermented oak sawdust for P. brevitarsis and A. dichotoma and wheat bran for T. molitor. The various feed additives are blended with each farm's own recipes. The overall growth condition, including sawdust fermentation method, feeding period, and rearing density, varies among the investigated farms. It seems that weight of last instar larva was correlated with the rearing density and duration of the larval period. The heavy metal contents were analyzed after 48 hour starvation and they were very small amount or not detected in investigated insects. We believe that the present data will contribute to develop and standardize the safe rearing techniques of edible insects in Korea.

• Journal of Life Science
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• v.27 no.10
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• pp.1185-1190
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• 2017

Insects are gaining recognition as an alternative source of protein. As a result, more and more domestic farms have begun mass rearing of edible insects. In order to produce high quality insects, studies on the development of safe and nutritious feed sources are needed. Given the cost of rearing insects, agricultural and industrial by-products are good sources for feed. The efficient utilization of these by-products can help in reducing the cost of production and preventing environmental pollution. In the current study, Citrus unshiu peel (CP), soybean curd cake (SCC), soybean oil meal (SOM), and brewers dried grain (BDG) were investigated for their effects on larval growth and development of Protaetia brevitarsis. Interestingly, the feed with 10% SCC increased larval weight by 3.5 times. For the larval period, the group of 10% SCC was significantly shorter than the control. Furthermore, minerals such as Zn, Ca, K, Mg, Na, and P were recorded to be high in 10% SCC. A total of 17 amino acids were present in 10% SCC, of which tyrosine and arginine were predominant. The heavy metal contents were very small amounts or not detected in any of the investigated groups. These findings provided a scientific basis for the utilization of soybean curd cake as a nutritional feed source to promote larval growth and produce quality insects.

• Journal of Life Science
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• v.28 no.5
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• pp.563-568
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• 2018

The insect industry is a promising agricultural resource and expected to grow steadily. In Korea, Gryllus bimaculatus and the larvae of Tenebrio molior, Protaetia brevitarsis, and Allomyrina dichotoma were listed as general food ingredients. As interest in these edible insects increases, rearing techniques and nutritious food sources are needed for mass production. In this study, wheat bran, dog feed, and pig feed were investigated for their effects on the larval growth of P. brevitarsis and A. dichotoma. When fermented sawdust with 30% wheat bran was used, the larval survival rate of P. brevitarsis and A. dichotoma (p=0.244341 and p=0.007966, respectively) and growth rate (p=0.001400 and p=0.000051, respectively) were significantly lower than those of the control (fermented sawdust with no supplement). Therefore, fermented sawdust with a high density of wheat bran was inappropriate for both insects. When fed fermented sawdust with 2.5 or 5% of dog and pig feed, the survival rate and growth rate of the larvae were higher than those of the control. Interestingly, the maximum larval weight with 2.5% dog feed was increased by $3.35{\pm}0.10g$ and $32.59{\pm}0.79g$ for P. brevitarsis and A. dichotoma, respectively. In addition, the larval period of both was shorter than that of the control by 40 days or more. Therefore, it is considered that animal feed can be used as a feed source for these edible insects.

• Archives of design research
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• v.17 no.1
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• pp.163-178
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• 2004

In this study, in order to achieve the before-mentioned study purpose, the importance of developing the new product, the relationship with the design, and the design element for developing the new product were considered. In order to extract the importance of the design element which is applied to the development of the new product design, the research model about the induction of the priority was created, the evaluation items were instituted, and the demonstrative research approach was performed in order to recognize the relationship among those elements. Firstly, in the process of selecting the items for the application, 14 evaluation elements which were extracted through the advanced study data were grouped in 4 kinds of dimensions, and the properties which are related with the Digital TV product were composed up of 36 items. Through the factor analysis, by decreasing the detailed standard for the evaluation of 36 items, the parsimony was secured, and the characteristics which the various items contain induced into one factor. Secondly, the detailed factors which were united into one factor went under the paired comparison as one by one through AHP again, and then the importance degree was generated. First of all, as the first stage of AHP, the decision making factors which affect the whole achievement of purpose of the decision making were classified as in a hierarchical style. From these research results, it was known that the functional factor and esthetic factor in the process of designing the new product are the major affecting variables, and it was confirmed that in case of the Digital TV products group, the factors such as the high quality of picture, big screen, user interface, sound, product reliability, style, size, indoor reproduction, and guarantee are the main factors which influence the need of the consumers in purchasing products.

• Korean Journal of Food Science and Technology
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• v.50 no.3
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• pp.297-307
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• 2018

The aim of this study was to develop a seasoning paste fermented by Aspergillus oryzae and Bacillus subtilis using three edible insects: Tenebrio molitor larvae, Gryllus bimaculatus, and Bombyx mori pupa. No significant changes in pH and titratable acidity were observed between the insect pastes and soybean control during a 5-week fermentation process. The amino nitrogen was 0.35-0.50% (w/w) in the early stage of the fermentation and increased to 0.72-0.78%. The total nitrogen was 2.36-3.62% (w/w) in the early stage and was preserved during the fermentation period. Free amino acids of the insect pastes were similar to those in soybean paste. In general, the fermented insect pastes showed a lower flavor and color than soybean paste but B. mori pupa-fermented paste did not show any significant difference in preference from soybean. Glutamate, aspartate, lysine, phenylalanine, arginine, and serine were found to affect taste preference. It was possible to ferment edible insect protein to produce a fermented seasoning paste like Korean doenjang.

• Journal of Life Science
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• v.28 no.12
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• pp.1501-1506
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• 2018

Edible insects have recently been increasingly promoted as a source of protein. As the number of farms rearing these insect increases, it is important to develop safe and nutritious feed sources to improve their commercial quality. The aim of the current study was to determine the effect of food by-products as feed supplements for the Korean rhinoceros beetle, Allomyrina dichotoma, which has been registered as a general food ingredient in Korea. We compared the effects of waste citrus peel, soybean curd cake, soybean oil meal, and brewers' dried grain on the growth of third instar larvae of A. dichotoma. Groups of larvae were fed with fermented sawdust and nine different combinations of the above by-products and the effects on their growth were measured until pupation. The highest survival rate was with feed supplemented with 10% brewers' dried grain (66.7%, p<0.05), and these larvae were also 26% heavier (p<0.05) than the control group that received no supplementation. In the 10% brewers' dried grain group, the larval period of third instar was shortened by almost 28 days (p<0.01) compared to the control group. Of all the groups, only that which was fed the brewers' dried grain supplement showed more than a 90% pupation rate (p<0.05). Therefore, brewers' dried grain may be useful as a source of feed for A. dichotoma.

• Science of Emotion and Sensibility
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• v.26 no.3
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• pp.3-14
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• 2023

This study used intersubject representational similarity analysis (IS-RSA) to identify participant-response consistency patterns in previously published data. Additionally, analysis of variance (ANOVA) was utilized to detect any variations in the conditions of each experiment. In each experiment, a combination of ASMR stimulation, visual and auditory stimuli, and time-series emotional video stimulation was employed, and emotional ratings and physiological measurements were collected in accordance with the respective experimental conditions. Every pair of participants' measurements for each stimulus in each experiment was correlated using Pearson correlation coefficient as part of the IS-RSA. The results of study revealed a consistent response pattern among participants exposed to ASMR, visual, and auditory stimuli, in contrast to those exposed to time-series emotional video stimulation. Notably, the ASMR experiment demonstrated a high level of response consistency among participants in positive conditions. Furthermore, both auditory and visual experiments exhibited remarkable consistency in participants' responses, especially when subjected to high arousal levels and visual stimulation. The findings of this study confirm that IS-RSA serves as a valuable tool for summarizing and presenting multidimensional data information. Within the scope of this study, IS-RSA emerged as a reliable method for analyzing multidimensional data, effectively capturing and presenting comprehensive information pertaining to the participants.

• Korean Journal of Clinical Laboratory Science
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• v.56 no.2
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• pp.135-146
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• 2024

Urinalysis is a fundamental diagnostic test routinely performed in clinical laboratories. We evaluated two manual microscopy methods, including a novel protocol, against the standardized chamber method. A total of 402 specimens, comprising 201 positive each for red blood cells (RBCs) and white blood cells (WBCs) by the strip test and automated urine sediment analyzer, were selected for the analysis. The correlation coefficients between the standardized chamber method and the novel protocol RBC and WBC test were both r=0.98, indicating a high degree of correlation. The pair-wise agreement rates for the same grade between these two methods were 86.1% for RBCs and 88.6% for WBCs, with rates within one grade difference of both at 99.5%. In contrast, the agreement rates between the standardized chamber method and smaller or medium-sized laboratory methods were notably lower, with the same-grade rates at 11.9% for RBCs and 13.4% for WBCs, and within one grade difference at 67.2% and 74.1%, respectively. Additional analyses using the intraclass correlation coefficient and Bland-Altman plots confirmed that the novel protocol exhibited superior agreement compared to the other three manual microscopy methods tested. Therefore, we recommend the novel protocol as a standardized procedure for urine sediment preparation, given its high correlation and agreement with the standardized chamber method.

• Korean Journal of Food Science and Technology
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• v.52 no.4
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• pp.317-324
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• 2020

In order to create the national food nutrient database, a total of 41 animal foods (ham, seafood, edible insects and eggs) were analyzed for their vitamin B₁₂ content and the applied immunoaffinity-HPLC was verified. Ham vitamin B₁₂ contents were 0.30-0.65 ㎍/100 g. Seafood showed relatively high vitamin B₁₂ level, where the values of fermented clam were the highest (26.80 ㎍/100 g) followed by fermented pollack roe. Vitamin B₁₂ was not detected in silkworm pupae and beetles, while relatively high levels were found in the two-spotted cricket imago (6.70 ㎍/100 g). Chicken and quail egg yolk had roughly 100- and 30-times higher vitamin B₁₂ levels as compared to their egg white. Vitamin B₁₂ contents in quail and chicken eggs were significantly enhanced by boiling (p<0.05). Results based on accuracy (97-102% recovery) and precision (<5% RSD) indicate that this study provides reliable vitamin B₁₂ information on animal foods consumed in Korea.