• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.9
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• pp.536-547
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• 2020

This study analyzed the correlation between adolescents' smartphone addiction as well as depression, self-esteem, and self-regulation based on QEEG (Quantitative Electroencephalogram) analysis. The study period was from March 19 to July 12, 2019, and the subjects were 76 students at P Middle School in Gyeonggi-do (normal group 47, risk group 29) who filled out a questionnaire and were subjected to quantitative EEG. The data analysis was performed via frequency analysis, independent t-test, correlation analysis, and path analysis of the IBM SPSS Statics 21.0 program. First, smartphone addiction had a positive correlation with depression. Second, smartphone addiction showed a negative correlation with self-esteem and α wave. Third, depression showed a negative correlation with self-esteem, which did not show a significant correlation with self-regulation. Fourth, depression was higher in the risk group than the normal group. For self-esteem, the normal group scored higher than the risk group. Self-regulation showed higher significant differences with the normal group than the risk group. Fifth, for α wave and SMR, the normal group scored higher than the risk group. Sixth, α waves had a negative effect on smartphone addiction. This study is meaningful in that it applied a brain science approach using quantitative analysis for objective evaluation of smartphone addiction.

• Journal of the Korean Society for Nondestructive Testing
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• v.26 no.2
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• pp.99-107
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• 2006

Magnetic nondestructive testing is very useful far detecting a crack on the surface or near of the surface of the ferromagnetic materials. The distribution of the magnetic flux leakage (DMFL) on a specimen has to be obtained quantitatively to evaluate the crack. The magnetic camera is proposed to obtain the DMFL at the large lift-off. The magnetic camera consists of a magnetic source, magnetic lens, analog to digital converters (ADCs), interface, and computer. The magnetic leakage fields or the distorted magnetic fields from the object, which are concentrated on the magnetic lens, are converted to analog electrical signals tv arrayed small magnetic sensors. These analog signals are converted to digital signals by the ADCs, and are stored, imaged, and processed by the interface and computer. However the magnetic camera has limitations with respect to converting and switching speed, full range and resolution, direct memory access (DMA), temporary storage speed and volume because common ADCs were used. Improved techniques, such as those that introduce the operational amplifier (OP-Amp), amplify the signal, reduce the connection line, and use the low pass filter (LPF) to increase the signal to noise ratio are necessary. This paper proposes the exclusive embedded ADC including OP-Amp, LPF, microprocessor and DMA circuit for the magnetic camera to satisfy the conditions mentioned above.

• Korean Journal of Ecology and Environment
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• v.42 no.3
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• pp.404-406
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• 2009

This study note wished to introduce special-purpose ship for algae removal that is developed by core technology of our country. The ship is consisted of main frame and adjuvant that can attach and detach as cross (+) shape of a character. The characteristics of ship are super light weight and low draft. That is consisted of four devices as suction, collection, filtration and recovering units. Among these, filtration used screen filter (mesh size 30 ${\mu}m$). Also, can separate and remove water and algae by compression air participle notion. Percentage of moisture content of concentrated algal particle was 85%. Water parted with algae finally is exhausted to water area. Removal efficiency that compare by chlorophyll-$\alpha$ concentration was about 57% (inflow: 83.2 ${\mu}g\;L^{-1}$, outflow: 35.8 $[\mu}g\;L^{-1}$) without physical and chemical pretreatment. Forward, need to achieve effect test in various conditions (algal biomass, flow etc.) for efficiency and technological elevation of exclusion device. We wished to contribute in presuppression system construction of massive algal development that manage blue-green algae occurrence area effectively, and prevents spread as lower part of reservoir.

• Imaging Science in Dentistry
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• v.38 no.4
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• pp.203-208
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• 2008

Purpose : The purpose of this study was to develop a system for the measurement and simulation of the TMJ movement and to analyze the mandibular movement quantitatively. Materials and Methods : We devised patient-specific splints and a registration body for the TMJ movement tracking. The mandibular movements of the 12 subjects with facial deformity and 3 controls were obtained by using an optical tracking system and the patient-specific splints. The mandibular part was manually segmented from the CT volume data of a patient. Three-dimensional surface models of the maxilla and the mandible were constructed using the segmented data. The continuous movement of the mandible with respect to the maxilla could be simulated by applying the recorded positions sequentially. Trajectories of the selected reference points were calculated during simulation and analyzed. Results : The selected points were the most superior point of bilateral condyle, lower incisor point, and pogonion. There were significant differences (P<0.05) between control group and pre-surgical group in the maximum displacement of left superior condyle, lower incisor, and pogonion in vertical direction. Differences in the maximum lengths of the right and the left condyle were 0.59${\pm}$0.30 mm in pre-surgical group and 2.69${\pm}$2.63 mm in control group, which showed a significant difference (P<0.005). The maximum of differences between lengths of the right and the left calculated during one cycle also showed a significant difference between two groups (P<0.05). Conclusion : Significant differences in mandibular movements between the groups implies that facial deformity have an effect on the movement asymmetry of the mandible. (Korean J Oral Maxillofac Radiol 2008; 38 : 203-8)

• Journal of the East Asian Society of Dietary Life
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• v.25 no.4
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• pp.667-671
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• 2015

This study investigated the antioxidant capacities and inhibitory activity of peeled lotus root (Nelumbo nucifera) as a food material on angiotension-converting enzyme (ACE). The antioxidant effects on total polyphenol and total flavonoid contents were not signicant. However, DPPH radical scavenging activity decreased from 85.07% to 80.70% by peeled treatment. SOD-like activity decreased from 20.84% to 17.97%, and ACE inhibitory activity decreased from 53.4% to 50.1% by peeled treatement. Thus, consumption of non-peeled lotus root should increase.

• The Journal of the Petrological Society of Korea
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• v.27 no.1
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• pp.25-36
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• 2018

The volcanic rocks around Mieukdo Island, Tongyeong, are classified as lower andesitic rocks (Jusasan Subgroup) and rhyolitic rocks (Unmunsa Subgroup), and upper andesitic rocks (Yokji Subgroup) and rhyolitic rocks (Saryang Subgroup). We confirmed their eruption timings and stratigraphic relationships, based on SHRIMP U-Pb zircon dating for zircons from major stratigraphic units of the subgroups. By the SHRIMP U-Pb dating, the samples yield the concordia ages of $88.95{\pm}0.44Ma$(n=11) in Punghwari Tuff and $82.56{\pm}0.95Ma$(n=10) in Chudo Tuff of the lower andesitic rocks, and $73.01{\pm}0.75Ma$(n=11) in Dara Andesite of the upper andesitic rocks. And then samples show a concordia age of $71.74{\pm}0.47Ma$(n=14) in Namsan rhyolite dyke of the upper rhyolitic rocks and an apparent age of $70.7{\pm}3.5Ma$ in granodiorite dyke, These data confirm the eruption or injection timings of the units and allow them to distinguish chronostratigraphy of Jusasan, Unmunsa, Yokji and Saryang Subgroups around the Mireukdo Island. In addition, the subgroups give a clue that can make a chronostratigraphical correlation with different volcanic units of the Late Cretaceous Yucheon Group in the Gyeongsang basin.

• Korean Journal of Plant Resources
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• v.33 no.6
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• pp.624-637
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• 2020

High-quality and high-phytonutrient watermelon fruits have strong market opportunities besides their health related benefits. Hence, investigating quality and nutritional related traits of watermelon genetic resources could provide important baseline data in breeding for increased lycopene content thereby increasing the marketability of watermelon. To this end, we have examined some fruit morphological traits and lycopene content of 105 genetic resources. Seeds, originally obtained from 22+ countries, were obtained from the National Agrobiodiversity Center, Jeonju, South Korea, grown in an experimental field and harvested at a fully mature stage. The size of pistil scar (SPS), the width of stripes (WS), weight of fruit (WF), length of fruit (LF), width of fruit (WIF), the thickness of pericarp (TP), soluble solids content (SSC), fruit shape in longitudinal section, ground color of skin, the intensity of the green color of skin, fruit shape at the apical part, grooving distribution, conspicuousness of stripes, and main color of the flesh were recorded on the field and inside laboratory and the lycopene was measured using spectrophotometric and HPLC methods. Watermelon fruits have shown a diverse morphological characters. Red and pink fleshed fruits dominated in the entire collections. Fruits with higher thickness of rind were found to exhibit less soluble solid content (SSC). Korean origin fruits were characterized by intermediate SSC while the United States of America (USA), Russia (RUS), Tajikistan (TJK), Turkmenistan (TKM), Taiwan (TWN), and Uruguay (URY) originated fruits had the highest SSC. The lycopene content varied between 41.37 and 182.82 ㎍/g, 2.81 and 163.72 ㎍/g, and 3.54 and 255.47 ㎍/g using HPLC, UV-Vis spectrophotometer, and microplate reader spectrophotometer, respectively. Red- and pink-fleshed fruits had the highest levels of lycopene content compared to the yellow- and orange-fleshed. Lycopene content had a significant positive correlation with SSC, however, no correlations were detected between lycopene and other quantitative fruit morphological characters. Our study demonstrated high diversity exists in fruit morphological traits and lycopene content of the germplasm collections which provide beneficial baseline data for a future breeding program and utilization of watermelon germplasm collections in gene banks for the maintenance and improvement of the current levels of production, marketability, and health-related benefit of watermelon fruits.

• Korean journal of food and cookery science
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• v.14 no.1
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• pp.1-8
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• 1998

The characteristics of Kimchi, associated with proceeding velocity of fermentation, and microbial changes, were investigated during fermentation where kimchi were prepared by the addition of different kinds of minor ingredients. In all samples, total acidity increased, and the pH and total reducing sugar content decreased as the fermentation proceeded. Redox potentials decreased from early to middle fermentation period but thereafter increased and had the lowest value at optimum ripening stage. The counts of total viable and lactic acid bacteria increased rapidly at the begining and decreased slowly. These bacterial counts of kimchi samples containing ginger, red pepper powder, and mixture of all minor ingredients were higher than those of other samples. The number of Leuconostoc mensenteroides reached the maximum at the optimum fermenting stage, Lactobacillus plantarum appeared at the time when Leu. mesenteroides reduced. All these phenomena were observed earlier in the samples containing raw red pepper and later in the samples added garlic than in other samples. It is suggested that garlic is the ingredient which improved storage capacity by prolonging fermentation period by lactic acid bacteria beneficial to less acidification, and ginger and red pepper powder are materials which gave better taste to kimchi by stimulating the growth of Leu. mesenteroids. And redox potential was an useful indicator in choosing optimum ripening time during fermentation.

• Journal of the Korean Data and Information Science Society
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• v.27 no.4
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• pp.865-874
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• 2016

This study was carried out to investigate the effect of dietary addition of herbal probiotics on the Hanwoo steers' physiochemical property. A total of 50 Hanwoo steers (5 treatment groups${\times}$10 heads) were used. The crude fat content of beef has been found significant high in T2 and T3 group, and the Con 2 group had the highest heating loss (p<0.05). The water-holding capacity ranged from 56.73% through 60.16%, and the treatment group was generally higher than the control group. In particular, the T3 group showed significantly high water-holding capacity (p<0.05). The cholesterol content ranged from 41.64mg/100g through 47.33mg/100g. In the overall and the Con 2 group had significantly high cholesterol content (p<0.05). Furthermore, the oleic acid and MUFA had significant high T2 and T3 group in the fatty acid composition (p<0.05), but the amino acid content made no difference between the treatment groups.

• Journal of the Korean Data and Information Science Society
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• v.27 no.5
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• pp.1307-1316
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• 2016

This study was to execute the random arrangement of total 120 heads (10 heads per treatment plot ${\times}$ 3 repeats ${\times}$ 4 treatment plots) for four breeds [Blue arakana commercial Fowl (BC), Yeonsan silky fowl (YS), Korean native fowl (KN), White leghorn fowl (WL)] with the initiation of laying hens at 32 weeks old in order to comparatively analyze egg quality and composition by sorts of laying hens. In case of evaluation of the quality of eggs, this study has shown that BC had higher degree of Haugh unit coefficient (82.82) and in case cholesterol content of eggs, BC had significantly low content as 317.55mg/100g, but YS had rather higher content as 381.30mg/100g. Furthermore, this study has found out that BC had significantly low Oleic acid (C18:1n9) and WL had higher Amino acid content by breeds than those of other breeds (p<0.05).