• 아시안잔디학회지
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• 제9권3호
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• pp.235-252
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• 1995

Turfgrass Rhizoctonia blight is a severe disease in golf courses in Korea. Attempts were made in 1989 to 1994 to identify the Rhizoctonia species associated with turfgrass blights and also to examine their epidemiology. A total of 120 Rhizoctonia isolates collected were identified as R. solani AG1, R. solani AG2-2, R. cerealis(AG-D) and R. oryzas from brown patch, large patch, yellow patch and white patch, re-spectively. R. solani AG1 was mostly associated with brown patch of cool-season grasses. and most frequently isolated in June through July and also in September. R. solani AG2-2 was isolated exclusively from zoysiagrasses from April to November, most frequently in June through July and October through November. R. cerealis was isolated frequently from both creeping hentgrass in March through April and in November, and zoysiagrass in April and July. Thermophilic R. oryzae was isolated only from creeping bentgrass in August, although with very low frequency. R. solani AG2-2 was strongly pathogenic specifically to Korean lawngrasses(Zoysia japonica, Z.matrella, Z. tenuifolia), but non-pathogenic to creeping bentgrass(Agrostis palustris), bermudagrass (Cynodon dactylon), Kentucky bluegrass(Poa pratensis), perennial ryegrass(Lolium prenne), and creeping red fescue(Festuca rubra subsp. ruhra L.). R. cerealis was strongly pathogenic to zoysiagrass and bentgrass only, but was isolate-specific i.e., from non-pathogenic to pathogenic, for other turfgrasses. The mycelial growth was optimum at relatively high temperature ranges of 25~30$^{\circ}C$ for R.solani AG1, AG2-2 and R. oryzae, while the mycelial growth of R. cerealis was initiated at $^{\circ}C$ and almost ceased at or above $^{\circ}C$.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 1995년도 봄 학술발표회 논문집
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• pp.99-106
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• 1995

The seismic responses of a base Isolated Pressurized Water Reactor(PWR) are investigated using a mathematical model which expresses the superstructure as a linear lumped mass-spring and the seismic Isolator as an equivalent spring-damper. Time history analyses are performed for the 1940 El Centre earthquake with linear amplification. In the analysis 5% of structural damping is used for the superstructure. The effects of high damping rubber bearing on seismic response of the superstructure in base isolated system are evaluated for four stiffness model types. The acceleration responses in base isolated PWR superstructure with high damping rubber bearings are much smaller than those in fixed base structure. In the higher strain region where stiffness behaves non-linearly, the acceleration responses modelled by one equivalent stiffness are smaller than those in nonlinear spring model, and the higher stiffness spring model of isolator exhibits larger peak acceleration response at superstructure in the frequency range above 2.0 Hz. when subjected to linearly amplified 1940 El Centre earthquake.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 2002년도 추계 학술발표회 논문집
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• pp.379-386
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• 2002

The objective of this study is to investigate the seismic demand on the isolated slab-on-steel girder bridge under cold climate conditions. To this end comparative test results are presented of laminated elastomeric and lead-rubber seismic isolators in warm and cold temperature conditions. At extremely cold temperatures, rubber "glass-harden" and as a result rubber bearings that may be used for seating bridges behave in a significantly non-linear fashion. From the nonlinear time history analysis of the isolated slab-on-steel girder bridge, larger forces are transferred to the substructures. however smaller displacement at superstructure is obtained under cold climate conditions. These phenomenons might need to be considered in design stage of the seismically isolated bridges.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 2005년도 학술발표회 논문집
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• pp.453-460
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• 2005

In this study, the seismic fragility analysis of a base isolated condensate storage tank installed in the nuclear power plant. The condensate storage tank is safety related structure in a nuclear power plant. The failure of this tank affect significantly to the core damage frequency of the nuclear power plants. The seismic analysis of the liquid storage tank was performed by the simple calculation method and the dynamic time storage analysis method. The convective and impulsive fluid mass is modeled as added masses proposed by several researchers. To evaluate the effectiveness of the isolation system, the comparison of HCLPF and core damage frequencies in non-isolated and isolated cases are carried out. It can be found from the results that the seismic isolation system increases the seismic capacity of a condensate storage tank and decreases the core damage frequency significantly.

• 한국세라믹학회지
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• 제22권3호
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• pp.7-12
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• 1985

A theoretical model describing the behavior of isolated pores during liquid phase sintering was developed and the experimental results obtained by the $80MgO-CaMgSiO_4$ specimens were given. Most of isolated pores once formed in the interior of specimen were not eliminated because the pressure of trapped non-diffusable gas in the pore like $N_2$ increases very rapidly with pore volume contraction. As sint-ering time increase it was observed that the number of pores decreases whereas the average size of pore increases. This phenomenon was interpreted in terms of the MgO growth during sintering which results in the coalescence of isolated pores. The increase of pore size resulting from pore coalescence was attributed to the main cause of the overfiring phenomena ; the higher sintering temperature or a long time sintering leads to a decrease in density.

• Journal of Power Electronics
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• 제13권4호
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• pp.507-515
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• 2013

This paper presents an isolated bidirectional dc/dc converter based on primary parallel isolated boost converter (PPIBC). This topology is an efficient solution in low voltage high power applications due to its ability to handle high currents in the low voltage side. In this paper, the converter has been modeled using non-ideal components and operated without any additional circuitry for startup using a digital soft-start procedure. Simulated and measured loop gains have been compared for the validity of the model. On-the-fly current direction change has been achieved with a prototype interconnecting two battery banks. A second prototype has been constructed and tested for supercapacitor operation in constant power charge mode.

• The Korean Journal of Physiology
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• 제4권2호
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• pp.45-51
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• 1970

In an attempt to better understand the effect of whole body irradiation on the spontaneous motility and oxygen consumption rate of the isolated mouse duodenum, a whole body X-irradiation of 1,000r. was given to albino mouse, and 1) the total length of contraction of isolated duodenum was recorded on kymograph every five minutes for 60 minutes, 2) glucose and 5-hydroxytryptamine(5-HT) were added to the reaction medium of Kreb's-Ringer-bicarbonate buffer(KRB) and response of the isolated duodenum to the drugs was observed, and 3) the oxygen consumption rate $(QO_2)$ of the isolated duodenum as well as the effect of glucose and 5-HT on $QO_2$ were measured by Warburg's standard manometric method and the comparison was made with the control(i.e. normal) group. The results thus obtained are summarized as follows. 1. The spontaneous motility of the isolated duodenum in the irradiated groups showed a significantly elevated pattern for the first 15 minutes comparing with the control. The motility, however, decreased after 15 minutes and remained so in the irradiated groups to the level of the nonirradiated control, but 24 hours post-irradiation group showed a tendency of an increased motility while one hour post-irradiation group showed no difference comparing with the control. 2. Addition of glucose produced generally elevated motility of the isolated duodenum in both irradiated and non-irradiated groups comparing with the control throughout the experiment, but no difference was observed in contractile amplitude between the irradiated and non·irradiated groups. 3. When 5-HT was added to the irradiated group, the contractile amplitude of isolated duodenum was similar to that of the control, and 5-HT alone caused a slight increase of the motility comparing with the control. 4. The oxygen consumption rate $(QO_2)$ of the isolated duodenum was found to be ,slightly increased in one hour post·irradiated group, but similar in 24 hour post·irradiated group comparing with the control. Glucose produced a significant increase of $QO_2$ in all the groups, but 5-HT produced a tendency of decrease of $QO_2$ in all the groups.

• 한국가금학회지
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• 제47권2호
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• pp.115-119
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• 2020

Fowl cholera is an infectious disease caused by Pasteurella multocida that contributes to high economic loss in the commercial chicken industry. Three Pasteurella multocida strains were isolated from outbreaks of acute fowl cholera in the Korean layer farms from 2018 to 2019. One strain was identified and serotyped using capsular PCR typing. This strain was also genotyped by lipopolysaccharide (LPS) PCR typing as A: L3, whereas other strains were non-typable. The multilocus sequence typing (MLST) result showed that the A: L3 strain is sequence type (ST) 134; the non-typable strains were recorded as the following new STs: ST 366 and ST 374. Using phylogenetic tree analysis based on MLST sequences, we determined that ST 366 and ST 374 are closely related to the reference strains that were previously isolated from duck and chicken in Korea, and they were highly prevalent within the Korean cluster. In conclusion, Pasteurella multocida strains were identified and isolated in this study. Furthermore, this is the first report of using MLST to determine the prevalence of fowl cholera in Korea.

• Journal of Microbiology and Biotechnology
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• 제17권6호
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• pp.993-1001
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• 2007

The technique of serological analysis of antigens by recombinant cDNA expression library (SEREX) uses autologous patient sera as a screening probe to isolate tumor-associated antigens for various tumor types. Isolation of tumor-associated antigens that are specifically reactive with patient sera, but not with normal sera, is important to avoid false-positive and autoimmunogenic antigens for the cancer immunotherapy. Here, we describe a selection methodology to isolate patient sera-specific antigens from a yeast surface-expressed cDNA library constructed from 15 patient lung tissues with non-small cell lung cancer (NSCLC). Several rounds of positive selection using patient sera alone as a screening probe isolated clones exhibiting comparable reactivity with both patient and normal sera. However, the combination of negative selection with allogeneic normal sera to remove antigens reactive with normal sera and subsequent positive selection with patient sera efficiently enriched patient sera-specific antigens. Using the selection methodology described here, we isolated 3 known and 5 unknown proteins, which have not been isolated previously, but and potentially associated with NSCLC.

• 미생물학회지
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• 제23권1호
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• pp.43-48
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• 1985

철저한 혐기적 방법으로 배양분리한 결과 편성 혐기성세균의 분리율이 높아졌고, 검체당 평균 3.3주가 분리되었다. 혈액배지인 NATB배지와 BA배지에서 비혈액배지인 NAT배지와 GAM배지에서 보다 세균 분리효과가 우수했다. NATB배지에는 혐기성 그람 양성 구균에 좋은 분리효과를 나타내었고, 그람 음성 간균은 15주 분리되었다. 이 중 Bacteroides가 12주로서 가장 많이 존재하는 균종이었다.