• Bulletin of the Korean Mathematical Society
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• v.47 no.5
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• pp.907-913
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• 2010

Let D be an integrally closed domain with quotient field K, * be a star operation on D, X, Y be indeterminates over D, $N_*\;=\;\{f\;{\in}\;D[X]|\;(c_D(f))^*\;=\;D\}$ and $R\;=\;D[X]_{N_*}$. Let b be the b-operation on R, and let $*_c$ be the star operation on D defined by $I^{*_c}\;=\;(ID[X]_{N_*})^b\;{\cap}\;K$. Finally, let Kr(R, b) (resp., Kr(D, $*_c$)) be the Kronecker function ring of R (resp., D) with respect to Y (resp., X, Y). In this paper, we show that Kr(R, b) $\subseteq$ Kr(D, $*_c$) and Kr(R, b) is a kfr with respect to K(Y) and X in the notion of [2]. We also prove that Kr(R, b) = Kr(D, $*_c$) if and only if D is a $P{\ast}MD$. As a corollary, we have that if D is not a $P{\ast}MD$, then Kr(R, b) is an example of a kfr with respect to K(Y) and X but not a Kronecker function ring with respect to K(Y) and X.

• Microbiology and Biotechnology Letters
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• v.30 no.2
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• pp.116-122
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• 2002

The partial 165 rDNA sequences of 6 lactic acid bacterial strains isolated from Kimchi were determined. Two strains were Leuconostoc mesenteroides and the rest were incorrectly classified and turned out to be Lactobacillus. As the case of dairy lactic acid bacteria, the strains isolated from Kimchi also had cell-envelope proteinase (CEP) activity. As the result of partial CEP gene amplification with CEP-specific primers, the expected 1.2-kb amplificate was obtained not from Leu. mesenteroides but from Lactobacillus strains. The deduced amino acid sequence of PCR product amplified from the genomic DNA of Lactobacillus pentosus KFR1821 showed 95％ and 92％ homology with those of PrtPs from Lactococcus lactis subsp. cremoris and Lactobacillus paracasei subsp. paracasei, respectively. The PCR amplificate was used as a probe and the result of Southern hybridization illuminated the location of CEP gene in chromosomal DNA of Lb. pentosus KFR1821.

• KSBB Journal
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• v.18 no.1
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• pp.45-50
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• 2003

In this study, the optimum conditions for mycelium culture of the mushroom Tricholoma matsutake and the inhibitory effect of the mycelium extracts no tyrosinase activity have been examined. When the extracts of the Tricholoma matsutake mycelia were tested for inhibitory activity on tyrosinase, it was found that the components extracted with ethyl acetate and water showed the highest inhibitory activity. The effect of antioxidants on the growth of mycelium and tyrosinase-inhibiting activity was also investigated. The results showed that tocopherol inhibited the growth in a concentration-dependent manner. In terms of tyrosinase-inhibiting activity, however, tocopherol was found to enhance the inhibitory activity.

• Composites Research
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• v.35 no.4
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• pp.255-260
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• 2022

Lightweight hydrant tanks increase the amount of water that can be carried by fire trucks, resulting in longer water spray times during the initial firefighting process, which can minimize human and property damages. In this study, the applicability of carbon-fiber-reinforced polymer (CFRP) composites as a material for lightweight hydrant tanks was investigated. In particular, the resin for manufacturing CFRP hydrant tanks must meet various requirements, such as excellent mechanical properties, formability, and dimensional stability. In order to identify a resin that satisfies these conditions, five commercially available resins, including epoxy(KFR-120V), unsaturated polyesters(G-650, HG-3689BT, LSP8020), vinyl ester(KRF-1031) were selected as candidates, and their characteristics were analyzed to investigate the suitability for manufacturing a CFRP hydrant tank. Based on the analyses, KRF-1031 exhibited the most suitable properties for hydrant tanks. Particularly, CFRP with KRF-1031 exhibited successful results for thermal stability and elution tests.

• The Journal of Korean Academy of Prosthodontics
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• v.38 no.5
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• pp.695-703
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• 2000

The purpose of this study was to evaluate the effects of fabrication and tightening methods of gold cyliner on the preload of the standard abutment. Three linear strain gauges (KFR-02N-120-C1-23, Kyowa, Japan) were mounted longitudinally on the 5.5mm Standard abutment (Nobel Biocare, Sweden) and three kinds of gold cylinders such as, as-received gold cylinder, gold cylinder after casting, and plastic cylinder after casting with type IV gold alloy were connected over the top of the standard abutment. Two kinds of tightening methods, such as manual torque with handhold screwdriver and electronic torque using Electronic torque controller were used to generate preload on the abutment. The result were as follows; 1. The preload generated by tightening cast plastic cylinder with handhold screw driver, was the lowest among the six groups. 2. The preload generated by cast plastic cylinder was lower than those by gold cylinders regardless of the tightening methods. 3. The electronic torque controller produced higher torque values than the handheld screwdriver.

• The Journal of Korean Academy of Prosthodontics
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• v.38 no.1
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• pp.98-107
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• 2000

Three linear strain gauges (KFR-02N-120-C1-23, Kyowa, Japan) were placed around the abutment of implant future and the maximum axial loads on the mandibular implants supporting over dentures were registered in experimental model when the overdenture was removed. The overdenture attachments used in this study were Round bar Hader bar, Dolder bar with and with out spacer. The retention of bar attachment was measured using universal testing machine while being con-trolled by Activating set and Deactivator except in case of the Hader bar. Simultaneously strains were recorded with the strain smart program in strain P-6000 series (Measurement group, Raleigh, USA). The maximum axial load was calculated and compared with each other. The results were as follows: 1. The amount and the timing of the maximum axial loads were different between the right and left implant in all attachment systems. 2. The retention of bar attachment except Hader bar could be adjusted but the controllability was different among the attachment systems. 3. The more the axial load, the higher the retention with Hader bar and Dolder bar without spacer. but the tendency of increase was not shown with round bar and Dolder bar with spacer.

• Journal of Radiation Protection and Research
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• v.20 no.4
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• pp.285-296
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• 1995

The site of Korea Final Repository, KFR, to collect and dispose of radioactive wastes produced in nuclear power plants will be selected to seaside. As all the radwastes stored temporarily in the site of power plants should be transported by the sea, Nuclear Environmental Management Center, NEMAC, of Korea Atomic Energy Research Institute, KAERI, has been developing the sea transport system to secure safe and efficient transportation of the radwastes from the power plant sites to the final repository. Investigating the status of advanced techniques of foreign countries for transport vessels and considering inland circumstances, the technical criteria of the transport vessel have been suggested in this study. Therefore, all the radwastes will be transported safely by the sea, without releasing any radioactive material to environment even in the case of accident.

• The Korean Journal of Mycology
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• v.43 no.2
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• pp.104-111
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• 2015

In this study, a new strain of Lentinula edodes (Shiitake) Poongnyunko was bred from dikaryotic KFRI 490 and monokaryotic KFRI 536 by Di-mon crossing method. In this study, the productivity was conducted through bed-log and sawdust substrate cultivation. The Poongnyunko showed significant intensive production from summer to autumn. Optimum temperatures of fruit-body formation were $17{\sim}24^{\circ}C$. The total amount of fruit-body production during 4 years by bed-log cultivation was $22kg/m^3$, and total yield of fruit-body until the 3rd flush was 648 g/ 2 kg. In case of sawdust substrate cultivation, the mycelial incubation period was 110~130 days. The suitable temperature and relative humidity were $18{\pm}1^{\circ}C$ and $90{\pm}5%$ respectively.

• Journal of Family Resource Management and Policy Review
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• v.18 no.2
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• pp.143-162
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• 2014

The purpose of this study is to analyze the influences on resource transfers between middle-aged parents and their married children. This study used 2009 data from the National Research Foundation of Korea regarding inter-generational resource transfers and preparation for later life (kfr-2009-c00010). A sample of 1208 households of middle-aged parents with married children was used. The study found that parents provided financial resource transfers to their married children in the following circumstances: where parents received financial resource transfers from their married children, where the household income of parents was high, where the children were younger, and where the children were male. Parents provided instrumental resource transfers to their married children in the following circumstances: where parents received instrumental resource transfers from their married children, where the gender of children was female, where the children were employed, where married children had their own children who were either younger than a preschooler, and where household incomes of married children were high. Parents received financial resource transfers from their married children in these circumstances: where their emotional ties with their children was high, where the household income of the parents was low, where the household income of the married children was high, and where married children had preschoolers. The circumstances in which parents received instrumental resource transfers from their married children were where parents provided instrumental resource transfers and the household incomes of married children were high.