• Journal of the East Asian Society of Dietary Life
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• v.5 no.1
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• pp.93-99
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• 1995

For the improvement of the L-lysine productivity of Brevibacterium flavum and Corynebacterium glutamicum, fusants were induced by interspecific protoplast fusion of Bacillus subtilis with C. glutamicum and B. flavum. The following results were obtained through protoplast formation of strains condition of protoplast fusion, characteristics of the fusants, and the productivity of lysine form starch. B. flavum BF-5 and C. glutamicum protoplasts were made by the treatment of 0.3unit/$m\ell$ of penicillin G at the early stationary growth phase for 2 hours followed by incubation with 10mg/$m\ell$ of lysozyme at 37$^{\circ}C$ for 120 min. When a mixture of the protoplast was treated with 30% PEG(M.W.6,000) solution containing 50mM CaCl2 at optimal conditions, the intergeneric fusion frequency between protoplasts of C. glutamicum CG-2 and B. subtilis BD 224 was 7.1${\times}$105. The genetic properties on the L-lysine producing fusants were compared with those of parental strains. As a results, the intergeneric fusants were completed in each auxotrophic requirement, resistances for S-(2-amino-ethyl)-L-cysteine and kanamycine were confirmed. And one of fusants selected, FBB-41 were found to be genetically stable fusants. The aspartokinase activity of FBB-41 strain increased than that of the parent strain.

• KSBB Journal
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• v.5 no.3
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• pp.255-261
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• 1990

Cell fusion between complementary mutants isolated from astaxanthin-producing yeast, Phaffia rhodozyma, was carried out to obtain astaxanthin-overproducing strains by protoplast fusion technique. The frequency of protoplast fusion was ranged from 2.3$\times$10-5 to 6.0$\times$10-5, and nuclear fusion in the cells of hybrids was demonstrated by several techniques such as isolation of recombinants after mitotic segregation of parental genetic markers, estimation of DNA content, direct observation of nuclei with nuclear staining, and comparison of survival rate to UV exposure. One of several hybrids, Fl, showed approximately 3-fold increase in astaxanthin content when compared with wild parent.

• Korean Journal of Microbiology
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• v.22 no.3
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• pp.175-181
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• 1984

In order to develope a protoplast fusion system for industrial coryneform bacteria, the optimum conditions for the formation and regeneration of progoplast were examined for Brevibacterium flavum and Corynebacterium glutamicum and the protoplast fusion was performed. For the formation of the protoplast of B. flavum and C. glutamicum, the optimum time for penicillin G. treatment to obtain protoplast was mid-exponential growth phase ($O.D_{580}=0.6-0.8,\;8.0{\times}10^7-1.0{\times}10^8cell/ml$). At the optimum conditions (0.3units/ml penicillin G and $400{\mu}g/ml$ lysoyme for treatement), frequencies of protoplast formation and protoplast regeneration were 99% and 25%, respectively. Protoplast regeneration frequency was highest under the optimum conditions for the protoplast formation. Addition of 25mM $Mg^{2+}\;and\;50mM\;Ca^{2+}$ to the regeneration medium further increased the regeneration frequencies. The protoplast fusion frequencies of B. flavum and C. glutamicum in intraspecies fusion were $1.0{\times}10^{-8}\;and\;7.8{\times}10^{-4}$, of the regenerated protoplast respectively, when 33% of PEG (polythylene glycol) 6,000 was used as the fusing agent.

• Proceedings of the KAIS Fall Conference
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• 2001.05a
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• pp.281-283
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• 2001

The low foamed high strengthen styrofoam samples made by dielectric heating are discussed. We used the oscillator which have the frequency of 13.6MHz and the Power of 7kW. 3 times expanded beads by steaming method were used in our foam-molding test. Internal fusion properties and density of internal structure were improved by dielectric foaming process. At the temperature of 105-110$^{\circ}C$, the internal fusion property was maximally improved.

• Restorative Dentistry and Endodontics
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• v.41 no.1
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• pp.55-62
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• 2016

Objectives: The purpose of this study was to investigate the incidence of root fusion and C-shaped root canals in maxillary molars, and to classify the types of C-shaped canal by analyzing cone-beam computed tomography (CBCT) in a Korean population. Materials and Methods: Digitized CBCT images from 911 subjects were obtained in Chosun University Dental Hospital between February 2010 and July 2012 for orthodontic treatment. Among them, a total of selected 3,553 data of maxillary molars were analyzed retrospectively. Tomography sections in the axial, coronal, and sagittal planes were displayed by PiViewstar and Rapidia MPR software (Infinitt Co.). The incidence and types of root fusion and C-shaped root canals were evaluated and the incidence between the first and the second molar was compared using Chi-square test. Results: Root fusion was present in 3.2% of the first molars and 19.5% of the second molars, and fusion of mesiobuccal and palatal root was dominant. C-shaped root canals were present in 0.8% of the first molars and 2.7% of the second molars. The frequency of root fusion and C-shaped canal was significantly higher in the second molar than the first molar (p < 0.001). Conclusions: In a Korean population, maxillary molars showed total 11.3% of root fusion and 1.8% of C-shaped root canals. Furthermore, root fusion and C-shaped root canals were seen more frequently in the maxillary second molars.

• Journal of Ceramic Processing Research
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• v.20 no.6
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• pp.589-596
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• 2019

Pigments with minute particle sizes, such as carbon black (CB) and pigment red 48:2 (P.R.48:2), are the most important types of pigment and have been widely used in many industrial applications. However, minute particles have large surface areas, high oil absorption and low surface energy. They therefore tend to be repellent to the vehicle and lose stability, resulting in significant increases in viscosity or reaggregation in the vehicle. Therefore, finding the best way to improve the dispersion properties of minute particle size pigments presents a major technical challenge. In this study, minute particle types of CB and P.R.48:2 were treated with nitrogen gas plasma generated via radio frequency-plasma enhanced chemical vapor deposition (RF-PECVD) to increase the dispersion properties of minute particles in deionized (DI) water. The morphologies and particle sizes of untreated and plasma treated particles were evaluated using scanning electron microscopy (SEM) and atomic force microscopy (AFM). The average distributions of particle size were measured using a laser particle sizer. Fourier transform infrared spectroscopy was carried out on the samples to identify changes in molecular interactions during plasma processing. The results of our analysis indicate that N2 plasma treatment is an effective method for improving the dispersibility of minute particles of pigment in DI water.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.26 no.8
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• pp.1121-1129
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• 2022

Object recognition is carried out using RGB images in various object recognition studies. However, RGB images in dark illumination environments or environments where target objects are occluded other objects cause poor object recognition performance. On the other hand, IR images provide strong object recognition performance in these environments because it detects infrared waves rather than visible illumination. In this paper, we propose an RGB-IR fusion model, high-frequency interchange network (HINet), which improves object recognition performance by combining only the strengths of RGB-IR image pairs. HINet connected two object detection models using a mutual high-frequency transfer (MHT) to interchange advantages between RGB-IR images. MHT converts each pair of RGB-IR images into a discrete cosine transform (DCT) spectrum domain to extract high-frequency information. The extracted high-frequency information is transmitted to each other's networks and utilized to improve object recognition performance. Experimental results show the superiority of the proposed network and present performance improvement of the multispectral object recognition task.

• Journal of the Korean earth science society
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• v.26 no.2
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• pp.114-128
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• 2005

Fuzzy information representation of multi-source spatial data is applied to landslide hazard mapping. Information representation based on frequency ratio and non-parametric density estimation is used to construct fuzzy membership functions. Of particular interest is the representation of continuous data for preventing loss of information. The non-parametric density estimation method applied here is a Parzen window estimation that can directly use continuous data without any categorization procedure. The effect of the new continuous data representation method on the final integrated result is evaluated by a validation procedure. To illustrate the proposed scheme, a case study from Jangheung, Korea for landslide hazard mapping is presented. Analysis of the results indicates that the proposed methodology considerably improves prediction capabilities, as compared with the case in traditional continuous data representation.

• Korean Journal of Microbiology
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• v.21 no.3
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• pp.156-162
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• 1983

Conditions for effcient formation and regeneration of protoplasts of Micromonospora rosaria and Micromonospora purpurea were investigated. The state of inoculm, culture stage and growth in a medium containing partially growth-inhibiting concentration of glycing have significant effects on portoplasting. A high frequency of regeneration (up to 30%) was accomplished with a hypertonic regeneration agar medium defined by Okanishi for Strptomyces. Using the optimal conditions for protroplasting and regeneration, protoplast fusion of auxotrophic M.rosaria was carried out. Polyethylene glycol 1,000 was chosen for fusogenic agent. When signgle auxotrophs were used, the recombinant frequency of auxortrophic markers varied from 1.3 to 3.2%. Using two double auxotrophs, the recombinant frequencies of 0.7-4.3% were obtained. Much lower frequencies(three or more orders of magnitude) were observed by the conventional matings.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.6 no.8
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• pp.35-40
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• 1983

The fusion frequency of flicker (F.F.F.) of 40 pupils were examined every day repeatedly, from Monday to Saturday. (1) The individual Variations of F.F.F. were statistically highly significant, p < 0.01 (2) Day to day Variations of F.F.F. were statistically highly significant, p < 0.01 (3) The interaction between age and weekly change was highly significant, p < 0.01 (4) The interaction between sex difference and weekly change was also significant, p < 0.01 (5) The interaction among age, sex and weekly change was significant at 1% level of significance.