• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.150.1-150.1
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• 2014

Showerhead is used as a main part in the semiconductor equipment. The face plate flatness should remain constant and the cleaning performance must be gained to keep the uniformity level of etching or deposition in chemical vapor deposition process. High operating temperature or long period of thermal loading could lead the showerhead to be deformed thermally. In some case, the thermal deformation appears very sensitive to showerhead performance. This paper describes the methods for robust design using computational fluid dynamics. To reveal the influence of the post distribution on flow pattern in the showerhead cavity, numerical simulation was performed for several post distributions. The flow structure appears similar to an impinging flow near a centered baffle in showerhead cavity. We took the structure as an index to estimate diffusion path. A robust design to reduce the thermal deformation of showerhead can be achieved using post number increase without ill effect on flow. To prevent the showerhead deformation by heat loading, its face plate thickness was determined additionally using numerical simulation. The face plate has thousands of impinging holes. The design key is to keep pressure drop distribution on the showerhead face plate with the holes. This study reads the methodology to apply to a showerhead hole design. A Hagen-Poiseuille equation gives the pressure drop in a fluid flowing through such hole. The assumptions of the equation are the fluid is viscous-incompressible and the flow is laminar fully developed in a through hole. An equation can be expressed with radius R and length L related to the volume flow rate Q from the Hagen-Poiseuille equation, $Q={\pi}R4{\Delta}p/8{\mu}L$, where ${\mu}$ is the viscosity and ${\Delta}p$ is the pressure drop. In present case, each hole has steps at both the inlet and the outlet, and the fluid appears compressible. So we simplify the equation as $Q=C(R,L){\Delta}p$. A series of performance curves for a through hole with geometric parameters were obtained using two-dimensional numerical simulation. We obtained a relation between the hole diameter and hole length from the test cases to determine hole diameter at fixed hole length. A numerical simulation has been performed as a tool for enhancing showerhead robust design from flow structure. Geometric parameters for the design were post distribution and face plate thickness. The reinforced showerhead has been installed and its effective deposition profile is being shown in factory.

• KSBB Journal
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• v.23 no.1
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• pp.65-69
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• 2008

The culture broth of a ${\beta}$-glucan-producing bacterium, Paenibacillus polymyxa JB115, was confirmed to show the antibiosis against pathogenic bacteria of livestock disease. The antibacterial substance produced by P. polymyxa JB115 exhibited strong bactericidal or bacteriostatic effect on the growth of livestock pathogenic bacteria including Staphylococcus aureus, Salmonella choleraesuis, Escherichia coli and Pseudomonas aeruginosa. This antibacterial substance also showed high stabilities in broad pH range (pH 3-11) and in broad temperature range $(40-121^{\circ}C)$, which is good enough to apply spray-dry method for the formulation of culture broth. It was also found that the antibacterial substance was very stable in artificial gastric fluid and bile acid, which implies the anticipated antibacterial activity against gastrointestinal bacteria harmful for livestocks. In conclusion, the culture broth of P. polymyxa JB115 can be developed as a multifuctional feed additive containing immune-enhancing ${\beta}$-glucan as well as antibacterial agent against livestock pathogenic bacteria.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.12
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• pp.310-320
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• 2017

The purpose of this study is to examine the effects of a chorus program in a local child center regarding character, social skills, problematic behaviors, and ADHD. Subjects of this study included 24 children in elementary schools participating in the daytime programs at a local child center located in Suwon, South Korea. The chorus program was comprised of 12 sessions of 60 minutes each, conducted from April 5-July 5, 2017. Results of this study were as follows: First, during the interviews on the character of the children before and after participation in the chorus program, it was noted that the children became more active in terms of the relationships with others and leadership. However, it was also noted that children were more active at the center than they were at their schools. Second, the differences in social skills before and after the chorus program among children were significant in overall social skills and their sub-variables, indicating that there were effective in adjusting social skills. Third, the differences in problematic behaviors before and after participation in the chorus program were significant only in overall problematic behaviors and excessive behavior. This indicates that the program was effective in improving problematic behaviors, particularly for excessive behavior. Fourth, the differences before and after participation in the chorus program in terms of ADHD were statistically significant for ADHD and its sub-variables of carelessness and hyperactivity impulsiveness. This indicates that there was an overall improvement in attention deficit/hyperactivity disorder. Therefore, the findings in this study showed that the chorus program was effective on enhancing character, social skills, problematic behaviors, and ADHD behaviors.

• Microbiology and Biotechnology Letters
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• v.41 no.3
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• pp.263-271
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• 2013

A xylanase-producing bacterium was isolated from a soil sample collected in Yongin city, Korea. The strain was aerobic and gram positive, and grew between pH 5.0 and 11.0, forming a yellow-colored colony. The strain was classified as a novel subspecies bacterium of Paenibacillus barcinonensis by 16S rRNA gene sequence similarity, phylogenetic analysis, phenotypic, and biochemical characteristics, and thus named Paenibacillus sp. HX-1. This strain produced extracellular endo-${\beta}$-1,4-xylanase, and the best xylanolytic activity (205.17 unit/ml) was obtained at 96 h in an optimized TNX medium containing 1% (w/v) bacto tryptone, 1% (w/v) NaCl, and 0.7% (w/v) beechwood xylan at pH 7.0, $37^{\circ}C$ and 200 rpm. The endo-${\beta}$-1,4-xylanase produced by the strain HX-1 yielded xylobiose as the end product from beechwood xylan hydrolysis. The enzyme exhibited optimum pH and temperature at pH 7.0 and $45^{\circ}C$, respectively. The remarkable enhancing effect of the TNX medium on xylanase production by HX-1, in spite of its simple formula, may have great advantages for industrial applications of xylanase.

• Korean Security Journal
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• no.54
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• pp.127-148
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• 2018

As the role and the importance of private security are emphasized in an independent way, as well as in a supportive way for police affairs, this study aims to figure out factors affecting job satisfaction of private security guards by investigating their job satisfaction. This study also suggests some solutions for improvement of their job satisfaction, such as enhancing task motivation and professionalism of private security guards. For the research were used SPSS(Statistical Package for the Social Science) WIN 24 programs. Frequency analysis, correlation analysis, multiple regression analysis and Crosstabulation analysis were performed as analytic methods. As a result of the study, the most fundamental factor in the job satisfaction of the private security guards was 'social recognition'. Social recognition forms when private security guards are trusted as professionals and the value of a job is enhanced. The policy recommendations to improve the job satisfaction of private security guards can be explained as follows. First, a government certification system should be established in an attempt to recruit professional private security guards. Second, in order to improve the work ability of private security guards, it is necessary to designate a special educational institution for a private security guards and provide systematic education. Third, the wage of private security guards should be readjusted to a realistic level. Fourth, it is necessary to secure substantial effect on the permission and the supervision of private security business. Finally, the business area based on public interest should be expanded.

• Journal of Technology Innovation
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• v.20 no.1
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• pp.199-234
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• 2012

Technology roadmaps (TRMs) are considered to be the essential tool for strategic technology planning and management. Recently, rapidly evolving technological trends and severe technological competition are making TRM more important than ever before. That is because TRM plays a role of "map" that align organizational objectives with their relevant technologies. However, constructing and managing TRMs are costly and time-consuming because they rely on the qualitative and intuitive knowledge of human experts. Therefore, enhancing the productivity of developing TRMs is one of the major concerns in technology planning. In this regard, this paper proposes a technology roadmapping approach based on function of which concept includes objectives, structures and effects of a technology and which are represented as Subject-Action-Object structures extractable by exploiting natural language processing of patent text. We expect that the proposed method will broaden experts' technological horizons in the technology planning process and will help to construct TRMs efficiently with the reduced time and costs.

• Biomolecules & Therapeutics
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• v.22 no.1
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• pp.17-26
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• 2014

${\alpha}$-Asarone exhibits a number of pharmacological actions including neuroprotective, anti-oxidative, anticonvulsive, and cognitive enhancing action. The present study investigated the effects of ${\alpha}$-asarone on pro-inflammatory cytokines mRNA, microglial activation, and neuronal damage in the hippocampus and on learning and memory deficits in systemic lipopolysaccharide (LPS)-treated C57BL/6 mice. Varying doses of ${\alpha}$-asarone was orally administered (7.5, 15, or 30 mg/kg) once a day for 3 days before the LPS (3 mg/kg) injection. ${\alpha}$-Asarone significantly reduced TNF-${\alpha}$ and IL-$1{\beta}$ mRNA at 4 and 24 hours after the LPS injection at dose of 30 mg/kg. At 24 hours after the LPS injection, the loss of CA1 neurons, the increase of TUNEL-labeled cells, and the up-regulation of BACE1 expression in the hippocampus were attenuated by 30 mg/kg of ${\alpha}$-asarone treatment. ${\alpha}$-Asarone significantly reduced Iba1 protein expression in the hippocampal tissue at a dose of 30 mg/kg. ${\alpha}$-Asarone did not reduce the number of Iba1-expressing microglia on immunohistochemistry but the average cell size and percentage areas of Iba1-expressing microglia in the hippocampus were significantly decreased by 30 mg/kg of ${\alpha}$-asarone treatment. In the Morris water maze test, ${\alpha}$-asarone significantly prolonged the swimming time spent in the target and peri-target zones. ${\alpha}$-Asarone also significantly increased the number of target heading and memory score in the Morris water maze. The results suggest that inhibition of pro-inflammatory cytokines and microglial activation in the hippocampus by ${\alpha}$-asarone may be one of the mechanisms for the ${\alpha}$-asarone-mediated ameliorating effect on memory deficits.

• Journal of Plant Biotechnology
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• v.37 no.2
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• pp.174-185
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• 2010

Full-length cDNAs are essential for the correct annotation of genomic sequences and for the functional analysis of genes and their products. To elucidate the functions of a large population of Chinese cabbage (Brassica rapa) genes and to search efficiently for agriculturally useful genes, we have been taking advantage of the full-length cDNA Over-eXpresser (FOX) gene hunting system. With oligo dT column it purify the each mRNA from the flower organs, leaf and stem tissue. And about 120,000 cDNAs from the library were transformed into $\lambda$-pFLCIII-F vector. Of which 115,000 cDNAs from the library were transformed into T-DNA binary vector, pBigs for transformation study. We used normalized full-length cDNA and introduced each cDNA into Arabidopsis by in planta transformation. Full-length Chinese cabbage cDNAs were expressed independently under the CaMV 35S promoter in Arabidopsis. Selfed seeds were harvested from transgenic Arabidopsis. We had selected 2,500 transgenic plants by hygromycin antibiotic tolerant test, and obtained a number of transgenic mutants. Each transgenic Arabidopsis was investigated in morphological changes, fertility and leaf colour. As a result, 285 possible morphological mutants were identified. Introduced cDNA was isolated by PCR amplification of the genomic DNA from the transgenic mutants. Sequencing result and BLAST analysis showed that most of the introduced cDNA were complete cDNAs and functional genes. Also, we examined the effect of Bromelain on enhancing resistance to soft rot in transgenic Chinese cabbage 'Osome'. The bromelain gene identified from FOX hunting system was transformed into Chinese cabbage using Agrobacterium methods. Transformants were screened by PCR, then RT-PCR and real time PCR were performed to analyze gene expression of cysteine protease in the T1 and T2 generations. The anti-bacterial activity of bromelain was tested in Chinese cabbages infected with soft rot bacteria. The results showed that the over-expressed bromelain gene from pineapple conferred enhanced resistance to soft rot in Chinese cabbage.

• Journal of Life Science
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• v.26 no.12
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• pp.1438-1445
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• 2016

Yeast can be post-contaminated by the equipment, producer, or air, and this can degrade yogurt quality. This study aimed to demonstrate the yeast inhibiting effect in fermented milk by adding Lactobacillus paracasei and Lactobacillus rhamnosus along with current fermenting lactic acid bacteria such as Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus. A certain amount of yeast was added to fermented milk samples that were soon after stored at variable temperatures, and the number of yeast cells was counted periodically. The swelling phenomenon caused by the gas produced by the yeast in fermented products was also observed. In the two experiments, compared to the control, the L. paracasei- and L. rhamnosus-added-groups showed much slower rate of yeast appearance and lower frequency of swelling phenomena. This suggests that using a mixture of L. paracasei and L. rhamnosus in fermented milk inhibits the growth of yeast. Furthermore, if the products are stored at $10^{\circ}C$, post-acidification is rarely seen in the experimental group compared to the control group. This means that the organoleptic flavor can be kept consistent from the production day till the expiration day, resulting in improved organoleptic quality for customers. In other words, the use of L. paracasei and L. rhamnosus in fermented milk will result in the following positive effects: improvement in storage stability by delaying yeast appearance, increase in quality consistency by inhibiting post-acidification, and improved organoleptic quality by enhancing texture and flavor.

• Applied Biological Chemistry
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• v.8
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• pp.61-63
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• 1967

1. This experiment was carried out, as part of virgin soil application project conducted by Chung Buk Province in 1966, to determine the effect of application of field red soil to rice paddy for enhancing the fertility of sterile paddy soil. 2. This applied field soil from the mountain near Chung Buk College contains 1.31% of active iron. 3. The plots of 15,000 kg, 22,500 kg, 30,000 kg, and 7,500 kg had increased yields of 11%, 9%, 8%, and 6% in weight of unhulled rice, respectively. 4. Although any significance was not recognized among the levels of treatment at 5% level in F test, the plot of 15,000 kg was highly significant, and those of 22,500 kg and 30,000 kg significant, where as that of 7,500 kg was non-significant compared with the control. 5. It seems that the most effective amount of application is 15,000 kg/10 a in this experiment. 6. The infection rate of rice blast and neck rot decreased with the increased amount of application.