• Journal of applied mathematics & informatics
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• v.16 no.1_2
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• pp.515-524
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• 2004

We prove the local existence of solution for nonconvex-valued differential inclusion under time-varying state constraints.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.390-393
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• 2001

The optimal temperature, pH and aeration rate for spore production by Bacillus polyfermenticus SCD in 500 ml shake flask and 5-1 jar fermenter were found to be $32^{\circ}C$, 7.0 and 1.0 vvm. respectively. When batch culture processes was performed under optimized culture conditions. viable cells were $3.3{\times}10^{10}$ CFU/ml and spore cells were $3.3{\times}10^{10}$ CFU/ml. Fed-batch culture processes were also examined with regard to higer maximum viable cell and spore production. The highe viable cells and spores were obtained in 5-1 jar fermenter at 72 h cultivation time by strategy in an intermediate feeding mode with 60% glucose solution 150 ml and 5% soybean flour solution 150 ml fed to the fermenter twice, and the productivity of spore cells was significantly increased. Finally. volumetric productivity of spore cells on fed-batch culture indicated $9.9{\times}10^8$ CFU/ml/h, which was approximately 2 times higher than batch culture. Thus, fed-batch culture show a promise as an industrial production method.

• Proceedings of the KSR Conference
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• 2003.10b
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• pp.111-116
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• 2003

The Permanent Way consisting of rails and sleeper laid on ballast is a technically and economically viable solution. After two decades of targeted research and development activities Slab Track turned out to be a reasonable option on special fields. Slab Track proves that especially under extreme condition and loads - they reliably help stability and a long service life of track. Technical and experimental solution of slab track are particularly underlined. This paper presents a few Results of the experiments of SFRC slab tracks under fatigue load.

• Proceedings of the KSR Conference
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• 2001.10a
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• pp.508-513
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• 2001

State of the German high speed railway slab track were investigated. The Permanent Way consisting of rails and sleepers laid on ballast is a technically and economically viable solution. After two decades of targeted research and development activities Slab Track turned out to be a reasonable option on special fields.

• Food Science and Biotechnology
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• v.15 no.3
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• pp.458-461
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• 2006

To determine whether the toxicity of Bacillus cereus would be seen in human cell lines and mice, we screened B. cereus B-38B, B. cereus B-50B, and B. cereus KCCM40935 for genes that coded for 5 enterotoxins using the polymerase chain reaction and cultivated them for 17 hr, by whose time they had grown to $10^7-10^8$ colony-forming units (CFU) per milliliter. Cell-free supernatant was added to make up 1% of the total reaction solution. Human cells from normal lung, lung carcinoma, embryonic kidney, and cervical adenocarcinoma cell lines were grown in culture. The cytotoxicity induced by adding the reaction solution was indicated by cell death rates of 0 to 70%, depending on the bacterial strain involved and the cell line. A lethality of 20% was observed when B. cereus cultures containing $10^7-10^8$ viable cells were administrated orally to mice. Therefore, the culture of B. cereus containing $10^7-10^8$ viable cells seems to have high cytotoxicity on human cell lines and lethality on mice.

• Preventive Nutrition and Food Science
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• v.18 no.4
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• pp.292-295
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• 2013

Fermented whey solution presenting bifidogenic growth stimulation (BGS) activity was processed as prototypes such as sterilized fermented whey (SFW), spray-dried fermented whey (SDFW), and freeze-dried fermented whey (FDFW) and their BGS activities were compared. In optical density ($OD_{600}$) test, the BGS activity of three prototypes, which showed similar activities, were significantly different with non-fermented whey solution adjusted to pH 4.5 as a control (P<0.05). In viable cell count test, SDFW had the most positive influence than other prototypes on the BGS activity even though the difference was not significant. However, the activities of all prototypes were significantly different than the negative control (no addition). These results indicate that the processed prototypes of fermented whey solution show BGS activities and might be commercialized, with further evidences, in animal or human studies.

• Korean Journal of Social Welfare
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• v.48
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• pp.302-332
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• 2002

This study aimed at finding out the effectiveness of Solution-Focused Group Therapy Program in reducing delinquents' problematic behaviors and increasing their self-esteem, impulse control, communication with the parents and bettering their daily life habits. Thirty one male delinquents under probation from a Probation Center in Seoul were chosen and given a Solution-Focused Group Therapy for 30 hours. For a comparison purpose another 31 male delinquents were chosen from the same Center. To evaluate the effectiveness of the Program, items were selected and used from Rosenberg's Self-Esteem Scale. Youth Outcome Questionnaire Self Report 2.0, Brief Family Therapy Center-Child/Teen Solution Identification Scale. Participants' and parents' self-reports on participants' changes and session progress records were also used for qualitative evaluation. The results showed some positive changes in participants' self-esteem, self-control, communication style with parents, and daily life habits. No illegal act was reported after nine months upon this Program, which posits this type of Solution-Focused Group Therapy Program as a viable solution for the prevention and recidivism of juvernile crimes.

• Proceedings of the Ginseng society Conference
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• 1984.09a
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• pp.1-11
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• 1984

Ginseng cotyledon calli were cultured on 1/2MS media supplemented with combination of various growth regulators to induce more embryoids and plantlets in a short period. And tissues of ginseng root and calli were also incubated under various factors or conditions to establish methods for the isolation of viable protoplasts in Panax ginseng C.A. Meyer. The calli derived from cotyledon produced numerous embryoids in 1/2MS media containing 0.5mg/$\ell$ 2,4-D and 0.5mg/$\ell$ kinetin after 2 months' culture. But only shoot formation was less frequent. Further development of these embryoids occurred on 1/2MS medium supplemented with the same concentration of BA and GA. Viable protoplasts were isolated from the root tissue and callus of ginseng. The specific conditions for the isolation of viable protoplasts were required of ginseng materials, root tissue and callus, being processed. For the production of viable protoplasts from 1-year old ginseng root tissue, an enzyme mixture of $2\%$ cellulase 'Ono-zuka' and $0.5\%$ macerozyme, an enzyme solution pH of 5.2 to 5.8, a 7- to 8- hour incubation period at $28{\pm}1^{\circ}C$, and 0.9M mannitol as osmoticum in the cell enzyme mixture were optimum, while the treatments with an enzyme mixture of $2\%$ cellulase 'Onozuka', $2\%$ macerozyme and $1\%$ driselase, and 25-hour incubation period at $28{\pm}1^{\circ}C$, were more efficient for the production of viable protoplasts from ginseng callus.

• Microbiology and Biotechnology Letters
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• v.27 no.3
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• pp.230-235
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• 1999

This study was intended to develop a new rice product by the fermentation of saccharified rice solution using Bifidobacterium and to select an appropriate reducing agent to provide the anaerobic condition for the growth of Bifidobacterium during fermentation. The enhancement of the growth of Bifidobacterium in saccharified rice solution was achieved by the treatment of reducing agents such as ascorbic acid and cysteine. The physical and chemical properties of the fermented product were evaluated, and the effect of the reducing agents were compared between ascorbic acid and cysteine. The fermented product with the addition of ascorbic acid shows the lower pH and the higher titratable acidity comparing the product with the addition of cysteine. This indicated that ascorbic acid was more appropriate reducing agent than cysteine for the fermentation of the saccharified rice solution. The number of viable Bifidobacterium in the fermented product with the addition of ascorbic acid(2.2$\times$108~3.4$\times$108CFU/ml) was greater than that with the addition of cysteine (8$\times$107~2.8$\times$108CFU/ml). Ascorbic acid supplement also contributed better sensory properties, such as flavor, taste and overall acceptibility than cysteine supplement did.

• Membrane and Water Treatment
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• v.13 no.1
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• pp.39-49
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• 2022

Seawater desalination is doubtlessly a viable option to supply fresh drinking water. Nevertheless, RO (reverse osmosis) desalination plants in specific areas may be intermittently operated to match the imbalance between water demand and supply. Although a handful of works have been done on other membrane systems, few studies have attempted to mitigate fouling in intermittent RO systems. Accordingly, the objectives of this paper were to examine the effect of the intermittent operation on RO fouling; and to compare four intermittent operation modes including feed solution recirculation, membrane storage in the feed solution, deionized water (DI) recirculation, and membrane storage in DI water. Results showed that intermittent operation reduced RO fouling under several conditions. However, the extents of fouling mitigation were different depending on the feed conditions, foulant types, and membrane lay-up methods. When the feed solution was recirculated during the lay-up, the restoration of the flux was less significant than that by the feed solution feed-up. The use of deionized water during the lay-up was effective to restore flux, especially when the feed solution contains scale-forming salts (CaSO₄) and/or colloidal silica.