• Journal of Electrical Engineering and information Science
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• v.2 no.5
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• pp.129-133
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• 1997

A circuit model for a field emission triode has been proposed. The model parameters have been extracted from he fabricated silicon tip array and verified by comparing with the results simulated by circuit simulator(SPICE). The cut-off frequency can be calculated from the parametric capacitance and the transconductance values extracted from measurements. For the field emission triode, the capacitance of 3.45fF/tip and the transconductance of 0.94nS/tip have been measured under the emission current of 4.1nA/tip. From these values, the cut-off frequency is predicted to be 43 kHz but th measured one came out to be 6 kHz. because o the parasitic capacitance components.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.17 no.6
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• pp.61-67
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• 2018

The face milling cutter, which is mainly used for the face milling, is used to cut the Carbon steel(SM20C) in the machining center for 5 times and 10 times respectively. This study clarify the dimensional accuracy characteristics according to the number of fine machining varied the condition of cutting depth, table feed speed and spindle speed. Cutting depth is varied 0.05~0.2mm, table feed speed is varied 0.05~0.2mm/min and spindle speed is varied 1500~2500rpm. As a result, the dimensional accuracy was stable 6 times machining with table feed speed 150mm/min and 10 times machining with table speed 100mm/min and cutting depth 0.05mm regardless times of machining.

• Korean journal of applied entomology
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• v.61 no.4
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• pp.539-548
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• 2022

In recent decades, the world has entered a new era in terms of the number and variety of biological invasions, due to economic progress and transportation efficiency. Biological invasion is becoming more likely as demand for foreign fresh foods and decorative goods grows. Alien species continue to infiltrate Korea in a variety of ways, and disturb on the insect fauna of Korea. The goal of plant quarantine is to decrease the economic impact of alien pests on the agriculture and forestry industries. In this study, we focused on insects found in imported cut flowers from 1996 to 2020 using pest information system. Overall, 147,160 cut flowers (159 items) were imported into Korea from 69 countries during this time period. Throughout this time, 467 species of insects were found in all imported cut flowers to Korea, total 13,757 detections. They were classified as provisional regulated pests in 273 species, quarantine managed pests in 78 species, and non-quarantine pests in 118 species. Thysanoptera and Hemiptera had the largest number of alien insect detections (more than 80% of the alien insects) among the nine orders. The outcomes of this study have highlighted the need for ongoing inspection activities targeted at preventing quarantine alien pests from entering or incursion in Korea.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.22 no.2
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• pp.81-88
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• 2011

Objectives : This study examined the reliability and validity of the Korean version of Asperger Syndrome Diagnostic Scale (K-ASDS), to calculate the cut-off score in the diagnosis of Asperger syndrome. Further, we examined classification error rate when applying cut-off scores. Methods : One hundred sixty-seven children participated in this study, including 46 with Asperger syndrome, 26 with PDD or PDD NOS, 43 with ADHD, and 52 normal children. Results : An ANCOVA demonstrated no significant differences in the K-ASDS total score between the Asperger and the PDD & PDD NOS groups. However, these groups did show significantly higher scores than the ADHD and normal groups. Among the five subscales on the K-ASDS, the Asperger group obtained significantly higher scores on the language and cognition subscales than the PDD & PDD NOS groups. Two scales were found to be useful in distinguishing the Asperger group from the PDD & PDD NOS group through a discriminant analysis. According to an analysis of ROC curve, the cut-off score on the K-ASDS for the diagnosis of PDD including Asperger syndrome was 121. Conclusion : We discussed that K-ASDS has pretty limit.

• Journal of Applied Biological Chemistry
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• v.54 no.3
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• pp.190-196
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• 2011

Effectiveness of edible coatings containing soy protein isolate (SPI), in reducing oxidative browning and moisture loss during storage ($4^{\circ}C$) of cut apples, potatoes, carrots, and onions was investigated. The SPI coatings were shown to have antioxidative activity. Furthermore, addition of carboxymethyl cellulose (CMC) to the formulations significantly improved its antioxidative activity. Oxidative discoloration, as determined by Commission Internationale De I'Eclairage (CIE) lightness ($L^*$), redness ($a^*$), and yellowness ($b^*$) color scale, was significantly reduced (p <0.05) by SPI coating treatments over a storage time of 120 min. Loss of lightness was reduced by SPI coatings with and without CMC. These respectively showed 4.03 and 3.71% change of $L^*$ value compared to 8.56% for control. Browning of the control in cut potatoes was significantly increased by 106.6% in contrast to 34.3 and 35.2% for SPI coatings with and without CMC, respectively. The $b^*$ values also reflected effectiveness of SPI. Moisture barrier effect was significantly better for the treatments, compared to the control. SPI coatings reduced moisture loss in apples and potatoes, respectively, by 21.3 and 29.6% over the control. Cut onions did not show any treatment effect both in terms of browning and moisture loss. SPI coatings prove to be good moisture barrier and antioxidative property.

• Steel and Composite Structures
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• v.45 no.5
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• pp.621-640
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• 2022

In the present article, the vibration response of a geometrically imperfect bi-directional functionally graded plate (2D-FGP) with geometric discontinuities and micro-structural defects (porosities) has been investigated. A porosity model has been developed to incorporate the effective material properties of the bi-directional FGP which varies in two directions i.e. along the axial and transverse direction. The geometric discontinuity is also introduced in the plate in the form of a circular cut-out at the center of the plate. The structural kinematic formulation is based on the non-polynomial trigonometric higher-order shear deformation theory (HSDT). Finite element formulation is done using C° continuous Lagrangian quadrilateral four-noded element with seven degrees of freedom per node. The equations of motion have been derived using a variational approach. Convergence and validation studies have been documented to confirm the accuracy and efficiency of the present formulation. A detailed investigation study has been done to evaluate the influence of the circular cut-out, geometric imperfection, porosity inclusions, partial supports, volume fraction indexes (along with the thickness and length), and geometrical configurations on the vibration response of 2D-FGP. It is concluded that after a particular cut-out dimension, the vibration response of the 2D FGP exhibits non-monotonic behavior.

• Korean Journal of Food Science and Technology
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• v.38 no.2
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• pp.183-187
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• 2006

Surface browning, caused by cutting and other wound during minimal processing, is very important quality criterion to consumers. Shelf-life of fresh-cut potatoes was extended using natural antibrowning treatments. Fresh-cut potatoes dipped with licorice and green tea extracts were packed with LDPE film and stored at $4^{\circ}C$ for 14 days. Quality characteristics of fresh-cut potatoes were investigated during storage. During storage, L value decreased and PPO activity increased. PPO showed the lowest activity at around 7 days storage, during which browning was effectively inhibited in licorice- and green tea extract-treated potatoes. Total phenol and chlorogenic acid contents increased for 7 days. Results suggest natural licorice extracts with ascorbic acids are effective antibrowning agents for maintaining quality of fresh-cut potatoes.

• Food Science of Animal Resources
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• v.34 no.5
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• pp.665-673
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• 2014

We compared standard culture methods as well as conventional PCR and real-time PCR for the detection of Listeria monocytogenes (L. monocytogenes) in milk, cheese, fresh-cut vegetables, and raw beef that have different levels of background microflora. No statistical differences were observed in sensitivity between the two selective media in all foods. In total, real-time PCR assay exhibited statistically excellent detection sensitivity (p<0.05) and was less time consuming and laborious as compared with standard culture methods. Conventional culture methods showed poor performance in detecting L. monocytogenes in food with high levels of background microflora, generating numerous false negative results. While the detection of L. monocytogenes in fresh cut vegetable by culture methods was hindered only by L. innocua, various background microflora, such as L. innocua, L. welshimeri, L. grayi, and Enterococcus faecalis appeared on the two selective media as presumptive positive colonies in raw beef indicating the necessity of improvement of current selective media. It appears that real-time PCR is an effective and sensitive presumptive screening tool for L. monocytogenes in various types of foods, especially foods samples with high levels of background microflora, thus complementing standard culture methodologies.

• FLOWER RESEARCH JOURNAL
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• v.16 no.1
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• pp.57-62
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• 2008

The objective of this study was to investigate the effect of triazole compounds [hexaconazole ($50mg{\cdot}L^{-1}$), diniconazole ($50mg{\cdot}L^{-1}$), myclobutanil ($150mg{\cdot}L^{-1}$), difenoconazole ($50mg{\cdot}L^{-1}$), tebuconazole ($500mg{\cdot}L^{-1}$), and bitertanol ($50mg{\cdot}L^{-1}$)] on commercial quality improvement of cut flowers of Dendranthema grandiflorum 'Baegkwang' Plant height, cut flower length and internode length decreased by all triazole compounds. Plant height, cut flower length, internode length and flower neck length were shortened by treatment of $50mg{\cdot}L^{-1}$ diniconazole and $500mg{\cdot}L^{-1}$ tebuconazole. Flower neck was thickened by hexaconazole and myclobutanil. Flower diameter increased with myclobutanil and bitertanol, while it decreased with tebuconazole. Among physiological injury, open center increased with bitertanol treatment. Overall $50mg{\cdot}L^{-1}$ diniconazole and $500mg{\cdot}L^{-1}$ tebuconazole showed a possitive effect on length flower neck and increasing chlorophyll content, while decreasing plant height, cut flower length and diameter of flowers. Thus it is necessary to consider kind, concentration, and treatment times for effective control of cut flower quality.

• Horticultural Science & Technology
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• v.34 no.5
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• pp.799-806
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• 2016

A standard rose cultivar, 'To Dios'(Rosa hybrida) was selected for use as a cut flower from the progeny of a cross between 'Vanilla perfume' and 'Marcia' at the research and development division of the Goyang-si Agricultural Technology Center in 2013. 'Vanilla perfume', an orange-colored (RHS Orange Group 27C) standard rose cultivar with 48 petals, was used as the female plant. 'Marcia', a white-colored (RHS Green white Group 157B) standard rose cultivar with 96 petals was used as the male parent. A cross was made in 2009 and seedlings were produced. Selections were made between 2010 and 2013, and a plant with good cut flower traits was finally selected and named 'To Dios'. 'To Dios' is a standard rose with large flowers of 11.2 cm in diameter and 128 peach-colored (RHS Red Group 36B) petals per flower. Vase life of this cultivar is up to 15 days. It takes 47 days from pruning to blooming and cut flower productivity is approximately $160stems/m^2$ per year. 'To Dios' was registered as a new cultivar No. 4875 with the Korea Seed & Variety Service on March 19, 2014.